description stringlengths 2.98k 3.35M | abstract stringlengths 94 10.6k | cpc int64 0 8 |
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BACKGROUND OF THE INVENTION
The present invention relates to a concrete embedded insert, called an anchor bolt locator, for properly locating and supporting a bolt or anchoring member during the pouring and curing of a concrete member, such that bolt will be properly placed in the cured concrete.
A concrete slab member is a common structural element of modern buildings. Horizontal slabs of steel-reinforced concrete are used to construct slab foundations, floors, ceilings, decks and exterior paving.
Concrete slabs are built using formwork—a type of boxing into which the wet concrete is poured. Typically, if the slab is to be reinforced, steel reinforcing rods are used, and these are positioned within the formwork before the concrete is poured. This steel reinforcing is often called rebar. Plastic tipped metal, or plastic bar chairs are typically used to hold the reinforcing rods away from the bottom and sides faces of the formwork, so that when the concrete sets it completely envelops the reinforcing rods. For a slab resting on the ground, the formwork may consist only of sidewalls pushed into the ground. For a suspended slab, the formwork is shaped like a tray, often supported by a temporary scaffold until the concrete sets. The formwork is commonly built from wooden planks and boards, plastic, or steel. After the concrete has set the formwork can be removed or remain in place. In some cases formwork is not necessary—for instance, a ground slab surrounded by brick or block foundation walls, where the walls act as the sides of the tray and the hardcore earth acts as the base.
Concrete slab members are also typically built in a manner that allows for anchor members and fasteners to be built into the slab so that other building elements can be easily and securely anchored to the concrete member. It is very common to see a slab with many different bolts and fasteners protruding from the slab after it has cured and the formwork has been removed. These preset anchors or inserts are typically used for securing pipes or conduits to concrete ceilings, or for securing framing to a concrete foundation or floor.
When anchors such as bolts and threaded rod are to be embedded in a concrete slab, they must be supported during the concrete pour. It is important that the anchors are located properly in the slab and remain undisturbed during the pour, so that subsequent building elements can be attached to them properly. The proper location of anchors in slabs is especially important for decks where the anchor will fasten a safety railing to the deck and for lateral force resisting systems where the anchors must be placed carefully to provide the proper anchorage without interfering with other structural members. Proper location is also important for the integrity of the anchor and the strength of the anchorage. If the anchor is set too close or at an improper angle so that it is too close to the sides of the slab water penetrating into the slab can degrade the anchor, and the strength of the anchorage is also compromised if there is insufficient concrete surrounding the anchor.
Typically, certain of the anchors located in the slab will be located close enough to the edges of the slab that they can be supported by a member attached to the side formwork during the pour. Other anchors will be located sufficiently far away from the sides of the form that they must be supported in some other manner. Sometimes the anchors can be tied to and supported by the reinforcing rods. Other times it is preferable to support the anchor on the underlying surface of the formwork. The present invention is a free-standing anchor bolt locator that attaches to the underlying formwork and holds an anchor or bolt during the concrete pour. Many such devices appear in the patent literature, including: U.S. Pat. No. 5,957,644, granted Sep. 28, 1999, to James A. Vaughan, U.S. Pat. No. 5,050,364, granted Sep. 24, 1991, to Michael S. Johnson et. al., and U.S. Pat. No. 5,205,690, granted Apr. 27, 1993, to Steven Roth.
The present invention improves upon the prior art by providing an anchor bolt locator that is inexpensively manufactured on automatic die-press machines from sheet steel and a structural nut that does not require any welding, while also being easy to use and install with current, commonly-used building practices and anchor designs.
SUMMARY OF THE INVENTION
It is an object of the present invention is to provide an anchor bolt locator, and a method for making an anchor bolt locator that is economically efficient to produce. It is also an object of the present invention to provide an anchor bolt locator that is easy to use and install. These objects are achieved by forming the chair of the anchor bolt locator out of sheet metal, and forming the anchor bolt locator in such a way that a structural nut can be permanently attached to the sheet metal chair without having to weld the nut to the chair. In this manner an anchor bolt locator is formed that can receive a piece of threaded rod in the nut in the typical fashion currently used for creating threaded rod anchorages with the nut at the proper height for such an anchorage. This type of anchorage is typical in the industry and uses two structural nuts sandwiching a structural plate washer between them. The structural nut of the present invention is designed to serve as the lower nut for a double-nut and plate washer anchorage. By avoiding welding the nut to the chair the structural integrity of the nut is better preserved, and the process does not need to include a welding station. Welding can crack nuts, especially if they are heat treated.
It is also an object of the present invention to provide an anchor bolt locator where the connection between the threaded rod and the locator is easily made. This object is achieved by providing a central opening in the anchor bolt chair that allows the user to precisely position the anchor bolt locator, while also providing tongues that serve as stop to prevent the anchor from being inserted too far into the structural nut. The threaded rod is rotated into the nut and tongues or prongs stop the threaded rod from being inserted farther than is necessary into the nut. If the anchor is threaded too far into the nut, the bottom of the anchor may be placed too close to the bottom of the concrete form which can lead to degradation of the anchor, and it will also mean that less of the anchor protrudes from the top of the form for attaching other devices.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1A is a perspective view of the anchor bolt locator of the present invention.
FIG. 1B is an alternate perspective view of the anchor bolt locator of the present invention.
FIG. 1C is an exploded, perspective view of the anchor bolt locator of the present invention, showing the placement of fasteners to secure the anchor bolt locator.
FIG. 1D is a perspective view of the anchor bolt locator of the present invention, attached to and set in a concrete slab form.
FIG. 1E is a side view of the anchor bolt locator of the present invention, attached to and set in a concrete slab form, showing the concrete in the form.
FIG. 2A is a plan view of the blank of the chair of an anchor bolt locator of the present invention.
FIG. 2B is a plan view of a chair of an anchor bolt locator of the present invention, after openings have been cut in the chair, and the depression and the legs bent from the bridge of the chair.
FIG. 2C is a plan view of an anchor bolt locator of the present invention. The structural nut has been attached to the chair.
FIG. 2D is a sectional view of a chair of an anchor bolt locator of the present invention taken along line 2 D- 2 D of FIG. 2B .
FIG. 2E is a sectional view of a chair of an anchor bolt locator of the present invention taken along line 2 E- 2 E of FIG. 2B , with a structural nut shown above the chair and ready for placement in the chair.
FIG. 2F is a partial sectional view of an anchor bolt locator of the present invention similar to FIG. 2E , with the structural nut now set in place on the chair, and the chair having been modified to frictionally engage the nut, securing it in place.
FIG. 3A is a plan view of a blank of a chair of an anchor bolt locator of the present invention. The anchor bolt locator shown in FIGS. 3A-3F is similar to the anchor bolt locator shown in FIGS. 2A-2F , except the anchor bolt locator shown in FIGS. 3A-3F receives a smaller structural nut.
FIG. 3B is a plan view of a chair of an anchor bolt locator of the present invention, after openings have been cut in the chair, and the depression and the legs bent from the bridge of the chair.
FIG. 3C is a plan view of the anchor bolt locator of the present invention. The structural nut has been attached to the chair.
FIG. 3D is a sectional view of the chair of the anchor bolt locator of the present invention taken along line 3 D- 3 D of FIG. 3B .
FIG. 3E is a sectional view of the chair of the anchor bolt locator of the present invention taken along line 3 E- 3 E of FIG. 3B , with the structural nut shown above the chair and ready for placement in the chair.
FIG. 3F is a partial sectional view of the anchor bolt locator of the present invention similar to FIG. 3E , with the structural nut now set in place on the chair, and the chair having been modified to frictionally engage the nut, securing it in place.
FIG. 4A is a plan view of a blank of a chair of an anchor bolt locator of the present invention. The anchor bolt locator shown in FIGS. 4A-4F is similar to the anchor bolt locator shown in FIGS. 2A-2F and FIGS. 3A-3F , except the anchor bolt locator shown in FIGS. 4A-4F receives an even smaller structural nut.
FIG. 4B is a plan view of a chair of an anchor bolt locator of the present invention, after openings have been cut in the chair, and the depression and the legs bent from the bridge of the chair.
FIG. 4C is a plan view of the anchor bolt locator of the present invention. The structural nut has been attached to the chair.
FIG. 4D is a sectional view of the chair of the anchor bolt locator of the present invention taken along line 4 D- 4 D of FIG. 4B .
FIG. 4E is a sectional view of the chair of the anchor bolt locator of the present invention taken along line 4 E- 4 E of FIG. 4B , with the structural nut shown above the chair and ready for placement in the chair.
FIG. 4F is a partial sectional view of the anchor bolt locator of the present invention similar to FIG. 4E , with the structural nut now set in place on the chair, and the chair having been modified to frictionally engage the nut, securing it in place.
FIG. 5A is a plan view of a blank of a chair of an anchor bolt locator of the present invention. The anchor bolt locator shown in FIGS. 5A-5F is similar to the anchor bolt locator shown in FIGS. 2A-2F , FIGS. 3A-3F and FIGS. 4A-4F , except the anchor bolt locator shown in FIGS. 5A-5F receives an even smaller structural nut.
FIG. 5B is a plan view of a chair of an anchor bolt locator of the present invention, after openings have been cut in the chair, and the depression and the legs bent from the bridge of the chair.
FIG. 5C is a plan view of the anchor bolt locator of the present invention. The structural nut has been attached to the chair.
FIG. 5D is a sectional view of the chair of the anchor bolt locator of the present invention taken along line 5 D- 5 D of FIG. 5B .
FIG. 5E is a sectional view of the chair of the anchor bolt locator of the present invention taken along line 5 E- 5 E of FIG. 5B , with the structural nut shown above the chair and ready for placement in the chair.
FIG. 5F is a partial sectional view of the anchor bolt locator of the present invention similar to FIG. 5E , with the structural nut now set in place on the chair, and the chair having been modified to frictionally engage the nut, securing it in place.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1A , shows the preferred, non-welded anchor bolt locator 1 of the present invention made from a galvanized sheet metal chair 2 and a structural nut 3 attached to the chair 2 by way of a friction fit.
As shown in FIG. 1A , preferably the chair 2 of the anchor bolt locator 1 is a u-shaped body having a bridge 4 that connects two legs 5 and 6 . Preferably, the bridge 4 is substantially rectangular with pairs of opposed sides and the legs 5 and 6 of the chair 2 are connected to the bridge 4 at one pair of opposed sides. Preferably, the legs 5 and 6 of the chair 2 depend from the bridge 4 at right angles to the bridge 4 . Preferably, the plurality of legs 5 and 6 extend away from the top surface 7 of the of the bridge 4 .
As shown in FIGS. 1 E and 2 D- 2 F, the bridge 4 is formed with a depression 8 that receives the structural nut 3 . The structural nut 3 is connected to the bridge 4 by frictional engagement and is held securely in place. The inner surface 9 of the side wall 10 of the depression 8 in the bridge 4 frictionally engages with the outer surface 11 of the outer side wall 12 of the nut 3 . Preferably, the outer side surface 11 of the nut 3 is made with flat faces 13 to have a polygonal, preferably hexagonal, cross-section. As shown in FIGS. 1B , 2 C and 2 D, edge openings 14 may be formed in the side wall 10 of the depression 8 where the flat faces 13 of the outer surface 11 of the polygonal nut 3 meet at nut side edges 15 . These edge openings 14 are particularly needed when a deep depression 8 must be made for a tall structural nut 3 , and the metal of the side walls 10 must be particularly stretched to make the depression 8 . The edge openings 14 may also be formed in the side wall 10 to extend into the bottom floor 16 of the depression 8 where the nut side edges 15 meet the bottom end 17 of the nut. The side wall 10 of the depression 8 extends away from the top surface 7 of the bridge 4 .
As shown in FIGS. 2B and 2C , the depression 8 in the bridge 4 is formed with a bottom floor 16 that has a top surface 18 . As shown in FIGS. 1A-1E , the structural nut 3 is received in the depression 8 of the bridge 4 . As best shown in FIGS. 2C and 2E , the structural nut 3 has a top end 19 , a bottom end 17 , an internal, threaded bore 20 forming an internal, threaded side wall 21 , and an outer side wall 12 defining an outer surface 11 of the nut 3 . The bottom end 17 of the structural nut 3 rests on the top surface 18 of the bottom floor 16 of the depression 8 , and portions of the outer surface 11 of the outer side wall 12 of the structural nut 3 are in contact with and in frictional engagement with portions of the inner surface 9 of the side wall 10 of the depression 8 such that the structural nut 3 is secured to the chair 2 .
As shown in FIGS. 1A and 2E , preferably, the outer side wall 12 of the nut 3 extends at a right angle to the top and bottom ends 19 and 17 of the nut 3 . Preferably, the side wall 10 of the depression 8 in the bridge 4 extends at right angle to the generally planar portion 22 of the bridge 4 surrounding the depression, and the generally planar portion 22 of the bridge 4 surrounding the depression 8 extends at a right angle to the outer side wall 12 of the structural nut 3 .
Since the anchor bolt locator 1 is preferably made from thin sheet steel the bridge 4 and legs 5 and 6 are, preferably, generally planar, thin members. See FIGS. 2C and 2F . Preferably, a portion 22 of the bridge 4 surrounding the depression 8 in the bridge of the chair 2 is a substantially planar and relatively thin member. As such, the structural nut 3 between the top end 19 and the bottom end 17 will have a thickness that is substantially greater than the relatively thin portion 22 of the bridge 4 surrounding the depression 8 . Similarly, the depression 8 in the bridge 4 to accommodate the structural nut 3 will have a depth from the top surface 7 of the bridge 4 to the bottom floor 16 of the depression 8 , with portions of the side wall 10 of the depression 8 extending from the top surface 7 of the bridge to the bottom floor 16 of the depression 8 , and that depth of the depression 8 will be substantially greater than the relatively thin portion 22 of the bridge 4 surrounding the depression 8 .
As shown in FIGS. 1B and 2B , preferably, the depression 8 in the bridge 4 of the anchor bolt locator 1 is formed with an opening 23 in the bottom floor 16 . Preferably, the opening 23 is located at the center of the depression 8 and will align with the center of the internal bore 20 in the nut 3 . This allows for accurate placement of the anchor or threaded rod 24 . The opening 23 is preferably an irregular opening 23 that creates a plurality of tongues 25 that extend underneath and support the structural nut 3 at is bottom end 17 . Preferably, at least one of the tongues 25 that make up the bottom floor 16 of the depression 8 extends sufficiently inward from the side walls 10 of the depression 8 to extend past the internal side wall 21 of the structural nut 3 , so as to block the passage created by the internal bore 20 so as to interfere and stop the travel of any threaded rod or anchor 24 received and threaded into the internal passage 20 of the nut 3 past the bottom end 17 of the structural nut 3 .
As shown in FIGS. 1A and 1E , each leg 5 and 6 of the chair 2 is formed with a flow passage 40 to ensure that concrete 26 flows around and under the anchor bolt locator 1 and the threaded rod 24 attached to the nut 3 .
Mounting holes 27 are provided in the bridge 4 , preferably at all four corners of the bridge 4 . As shown in FIGS. 1C , 1 D and 1 E, fasteners 28 , preferably nails when the form board bottom 29 is wood, are inserted through the mounting holes 27 and fastened to the form board decking 29 , securing the anchor bolt locator 1 to the form 30 in the desired location.
The anchor bolt locator 1 is preferably formed from galvanized, stainless-steel formed in a sheet. Steel is sufficiently rigid, and can be cold-formed to grip the structural nut 3 after it has been placed in the depression 8 . In the preferred method of making the anchor bolt locator 1 , any openings that are to be made in the bridge 4 are formed first, usually with or right after the blank for the chair 2 is cut from the sheet stock. See FIGS. 2A , 3 A, 4 A and 5 A. Then, the depression 8 in the bridge 4 for receiving the nut 3 is formed and the legs 5 and 6 are bent down from the bridge 4 along bend lines 31 . See FIGS. 2B , 2 D, 3 B, 3 D, 4 B, 4 D and 5 B, 5 D. At the same time, embossments 32 are formed in the bridge 4 outwardly from the depression 8 . The depression 8 of the chair 2 is then ready to receive the nut 3 which is placed in the depression 8 . See FIGS. 2E , 3 E, 4 E and 5 E. The structural nut 3 is placed in the depression 8 so that portions of the outer surface 11 of the outer side wall 12 of the structural nut 3 are in alignment and in close proximity to portions of the inner surface 9 of the side wall 10 of the depression 8 . Once the nut 3 is received the embossments 32 formed outwardly from the depression 8 are clampingly pressed back into the original plane of the bridge 4 of the chair 2 . See FIGS. 2C , 2 F, 3 C, 3 F, 4 C, 4 F and 5 C, 5 F. This causes a spreading flow of the material of the embossments 32 toward the depression 8 which causes the side walls 10 of the depression 8 to be pressed against the outer side surface 11 of the nut 3 , causing frictional engagement that holds the structural nut 3 in place.
As shown in FIGS. 1B and 1C , preferably, the attachment between the anchor 24 and the nut 3 is made by means of corresponding threads in the internal cavity 20 of the structural nut 3 and threads 33 on the outer surface 34 of the anchor 24 . As shown in FIG. 1E , the anchor 24 is formed with an elongated shank 35 that can protrude above the top level 36 of the concrete slab 26 . FIG. 1E shows the top level 36 of the form 30 and the side wall 41 of the form 30 .
FIGS. 1D and 1E illustrate use of the invention. The anchor bolt locator 1 shown is used with a wood form 30 upon which concrete 26 will be poured. In FIG. 1D , rebar members 37 , a specific type of steel concrete reinforcing member, are shown placed in the form 30 . In FIG. 1D , chalk lines 38 are also shown on the bottom member 29 of the form 30 to aid in locating the anchor bolt locator 1 . The installer need merely look through the opening 20 in the nut 3 and line up the center of the opening 20 with the intersection of the chalk lines 38 . The installer then nails or screws the anchor bolt locator 1 to the bottom 29 of the form 30 by running the fasteners 28 through the mounting holes 27 in the anchor bolt locator 1 . Once the anchor bolt locator 1 is firmly fastened to the bottom 29 of the formwork 30 , the appropriate anchor 24 or threaded rod is inserted and threaded onto the nut 3 , until the tongues 25 of the depression 8 stop its further downward travel. As shown in FIG. 1E , typically a washer 38 will then be placed over the anchor 24 so that it rests on the top surface 19 of the structural nut 3 and a second structural nut 39 will be threaded onto the anchor 24 so that it engages the top surface of the washer 38 . This type of double-nut-washer anchorage is commonly used in the industry, because the components are readily available and inexpensive, and yet well documented for their performance as anchors. Concrete 26 is then poured into the formwork 30 , so that the anchor bolt locator 1 , the structural nuts 3 and 39 , the washer 38 , and the threaded rod 24 are all surrounded and embedded in the concrete 26 with the top of the threaded rod 24 or anchor protruding from the top surface 36 of the concrete 26 . When the concrete 26 hardens the form 30 can be removed. If there is access to the bottom 29 of the form 30 , it can be removed as well and the ends of the fasteners 28 that were driven into the bottom formwork 29 can be broken off where they protrude from the concrete foundation 26 . | An anchor bolt locator is provided that is inexpensively manufactured on automatic die-press machines from sheet steel and a structural nut that does not require any welding, while also being easy to use and install with current, commonly-used building practices and anchor designs. The anchor bolt locator is made from a galvanized sheet metal chair and a structural nut attached to the chair by way of a friction fit. | 4 |
PRIORITY CLAIM
This application is a Divisional of U.S. application Ser. No. 13/163,388, filed on Jun. 17, 2011, the content of said application incorporated herein by reference in its entirety.
FIELD OF TECHNOLOGY
The present application relates to Doherty amplifiers, in particular Doherty amplifiers designed for a wideband frequency range of operation.
BACKGROUND
RF (radio frequency) power architectures within the telecommunications field focus on achieving high DC-to-RF efficiency at significant power back off from Psat (the average output power when the amplifier is driven deep into saturation). This is due to the high peak to average ratio (PAR) of the transmitted digital signals such as W-CDMA (wideband code division multiple access), LTE (long term evolution) and WiMAX (worldwide interoperability for microwave access). The most popular power amplifier architecture currently employed is the Doherty amplifier. The Doherty amplifier employs a class AB main amplifier and a class C peaking amplifier, and efficiency is enhanced through load modulation of the main amplifier from the peaking amplifier. However, if high efficiency at a high output backoff (OBO) is required, a highly asymmetric ratio between the main and peaking amplifiers is required.
The Doherty architecture has an inherent degradation in the efficiency between the peak OBO point and the peak power point. To overcome this, a three way Doherty architecture can be used, in which the main class AB amplifier is replaced with a Doherty amplifier and load modulation is provided to the first peaking amplifier between the peak OBO point and the peak power point. However, the main amplifier is connected to the external load impedance (typically 50 Ohms) through a series of three ¼λ (quarter wavelength) transmission lines prior to any device impedance matching. This can lead to the amplifier being narrow band in nature due to the band-limiting characteristics of the ¼λ transmission lines. As such, three way Doherty amplifiers are typically designed for a specific band of operation used for wireless communication applications like WCDMA, LTE, WiMAX, etc. Such bands of operation are 1805-1880 MHz, 1930-1990 MHz, etc.
SUMMARY
Embodiments described herein employ a constant impedance combiner having a characteristic impedance equal to the required load modulated high impedance state of the main amplifier in a three way wideband Doherty amplifier circuit when the first and second peaking amplifiers are turned off. In this most narrow band case there is minimal band limiting presented to the main amplifier. A significant amount of band limiting is removed from the main amplifier path when running in the back off power region, yielding more constant power versus frequency and more constant efficiency versus frequency at a fixed back off power level. The amplifier embodiments described herein are well suited for wider band applications such that one amplifier circuit can simultaneously cover two or more adjacent bands of operation or be more consistent across a complete band of operation than currently existing architectures.
According to one embodiment of an amplifier circuit, the amplifier circuit includes a main amplifier biased at Class B or AB mode, a first peaking amplifier biased at Class C mode, a second peaking amplifier biased at Class C mode and a constant impedance combiner. The constant impedance combiner has a first node connected to an output of the main amplifier, a second node connected to an output of the first peaking amplifier, a third node connected to an output of the second peaking amplifier and a fourth node connected to a load. The constant impedance combiner is operable to transform a load impedance at the fourth node to a transformed impedance at the third node, and maintain the same transformed impedance at the first, second and third nodes.
According to one embodiment of a method of operating an amplifier circuit, the method includes: biasing a main amplifier at Class B or AB mode; biasing a first peaking amplifier at Class C mode; biasing a second peaking amplifier at Class C mode; connecting a first node of a constant impedance combiner to an output of the main amplifier, a second node of the constant impedance combiner to an output of the first peaking amplifier, a third node of the constant impedance combiner to an output of the second peaking amplifier, and a fourth node to a load; and transforming a load impedance at the fourth node to a transformed impedance at the third node so that the same transformed impedance is maintained at the first, second and third nodes.
According to another embodiment of an amplifier circuit, the amplifier circuit includes a first amplifier operable to turn on at a first power level, a second amplifier operable to turn on at a second power level below the first power level and a third amplifier operable to remain on at all power levels. A first power combiner is operable to combine an output of the third amplifier with an output of the second amplifier at a first power combining node to form a first combined amplifier output. A second power combiner is operable to combine the first combined amplifier output with an output of the first amplifier at a second power combining node to form a second combined amplifier output. An impedance transformer is operable to transform a load impedance of the amplifier circuit to a transformed impedance at the second power combining node, the transformed impedance matching an impedance of the first and second power combiners.
According to another embodiment of a method of operating an amplifier circuit, the method includes: turning on a first amplifier at a first power level; turning on a second amplifier at a second power level below the first power level; turning on a third amplifier at all power levels; combining an output of the third amplifier with an output of the second amplifier at a first power combining node to form a first combined amplifier output; combining the first combined amplifier output with an output of the first amplifier at a second power combining node to form a second combined amplifier output; and transforming a load impedance of the amplifier circuit to a transformed impedance at the second power combining node with no impedance transformation occurring from the second power combining node to the first power combining node.
According to an embodiment of a three way wideband Doherty amplifier circuit, the circuit includes a first peaking amplifier operable to turn on at a first power level, a second peaking amplifier operable to turn on at a second power level below the first power level and a main power amplifier operable to turn on at all power levels. The main power amplifier has a high impedance load modulated state when the first and second peaking amplifiers are turned off. The Doherty amplifier circuit further includes a constant impedance combiner connected to an output of each amplifier. The constant impedance combiner has a characteristic impedance which matches the impedance of the main amplifier in the high impedance load modulated state with or without an output matching device connecting the main amplifier output to the constant impedance combiner, as viewed from the output of the main amplifier.
Those skilled in the art will recognize additional features and advantages upon reading the following detailed description, and upon viewing the accompanying drawings.
BRIEF DESCRIPTION OF THE FIGURES
The elements of the drawings are not necessarily to scale relative to each other. Like reference numerals designate corresponding similar parts. The features of the various illustrated embodiments can be combined unless they exclude each other. Embodiments are depicted in the drawings and are detailed in the description which follows.
FIG. 1 illustrates a schematic circuit diagram of a three way wideband Doherty amplifier circuit having a constant impedance combiner according to an embodiment.
FIG. 2 illustrates a schematic circuit diagram of a three way wideband Doherty amplifier circuit having a constant impedance combiner according to another embodiment.
FIG. 3 illustrates a schematic circuit diagram of a three way wideband Doherty amplifier circuit having a constant impedance combiner according to yet another embodiment.
FIG. 4 illustrates a schematic circuit diagram of a three way wideband Doherty amplifier circuit having a constant impedance combiner according to still another embodiment.
FIG. 5 illustrates a schematic circuit diagram of a three way wideband Doherty amplifier circuit having a constant impedance combiner which provides no impedance transformation according to an embodiment.
DETAILED DESCRIPTION
FIG. 1 illustrates an embodiment of a three way wideband Doherty amplifier circuit which includes a main amplifier 100 biased at Class B or AB mode, a first peaking amplifier 110 biased at Class C mode, a second peaking amplifier 120 biased at Class C mode, and a constant impedance combiner 130 . Each amplifier 100 , 110 , 120 includes one or more active devices and may also include a respective output matching device 102 , 112 , 122 . At low power levels, only the main amplifier 100 is operational. The efficiency of the main amplifier 100 increases as the power level increases. The main amplifier 100 eventually reaches a maximum efficiency point as the power level continues to rise. At this power level, the first peaking amplifier 110 turns on. The efficiency of the first peaking amplifier 110 similarly increases for power levels above this point. A second maximum efficiency point is attained when the first peaking amplifier 110 reaches its maximum efficiency point, at which point the second peaking amplifier 120 turns on. The second peaking amplifier 120 reaches a third maximum efficiency at a yet higher power level (full power). As such, the three way wideband Doherty amplifier circuit has three maximum efficiency points.
Load modulation is implemented by the fundamental current ratio between the main amplifier 100 and the peaking amplifiers 110 , 120 . In addition, the constant impedance combiner 130 combines or sums the load currents of the amplifiers 100 , 110 , 120 so that the output voltage of the wideband Doherty amplifier circuit is determined by the summation of the load currents multiplied by the load impedance. In more detail, the constant impedance combiner 130 has a first node 132 connected to the output of the main amplifier 100 . In one embodiment, the first node 132 of the constant impedance combiner 130 is connected to the main amplifier output via an output matching device 102 . Input matching devices 104 , 114 , 124 may similarly be provided at the respective inputs of the amplifiers 100 , 110 , 120 . In another embodiment, the first node 132 of the constant impedance combiner 130 is directly connected to the main amplifier output and no impedance match device is provided for the main amplifier 100 as described in more detail later herein. In each case, the constant impedance combiner 130 also has a second node 134 connected to the output of the first peaking amplifier 110 and a third node 136 connected to the output of the second peaking amplifier 120 either of which may or may not also include a respective output matching device 112 , 122 .
The impedance of the main amplifier 100 in a high impedance load modulated state when the peaking amplifiers 110 , 120 are turned off is a function of the load cu rent delivered by the peaking amplifiers 110 , 120 . The main amplifier 100 operates in the high impedance state when the peaking amplifiers 110 , 120 are turned off and in a low impedance state when the peaking amplifiers 110 , 120 are turned on. For example, if the input power is relatively small so that neither peaking amplifier 110 , 120 is turned on, the impedance presented to the main amplifier 100 will increase (2× is indicative, but the impedance could increase from 1× to 4× or more based on the implementation) compared to its low impedance state. At low power level the output impedance of the peaking amplifiers 110 , 120 is theoretically infinite or very large when looking into the amplifier device on the output side after the corresponding output match network 112 , 122 from the second node 134 and the third node 134 of the constant impedance combiner 130 respectively, because the peaking amplifiers 110 , 120 are turned off and contribute zero load current.
The constant impedance combiner 130 has a characteristic impedance which matches the impedance of the main amplifier 100 in the high impedance load modulated state with or without the output matching network 102 connecting the main amplifier output to the constant impedance combiner 130 , as viewed from the output of the main amplifier 100 . In doing so, the output back off of the amplifier circuit has minimal bandwidth limitations which enables the amplifier circuit to be used in wideband applications.
In the embodiment illustrated in FIG. 1 , the constant impedance combiner 130 also has a first power combiner 138 with a first terminal 140 connected to the first node 132 of the constant impedance combiner 130 and a second terminal 142 connected to the second node 134 of the constant impedance combiner 130 . A second power combiner 144 has a first terminal 146 connected to the second node 134 of the constant impedance combiner 130 and a second terminal 148 connected to the third node 136 of the constant impedance combiner 130 . The first and second power combiners 138 , 144 have the same (i.e. identical or nearly identical) impedance.
The constant impedance combiner 130 further has an impedance transformer 150 having a first terminal 152 connected to the load 160 of the amplifier circuit and a second terminal 154 connected to the third node 136 of the constant impedance combiner 130 . The impedance transformer 150 is a wideband impedance transformer according to this embodiment in that the transformer 150 has a wider end and a narrower end. The narrower end may be connected to the load 160 and the wider end connected to the third node 136 of the constant impedance combiner 130 as shown in FIG. 1 . Alternatively, the wider end of the transformer 150 may be connected to the load 160 and the narrower end connected to the third node 136 of the constant impedance combiner 130 in other embodiments.
During operation, the wideband impedance transformer 150 transforms the load impedance at its first terminal 152 to a transformed impedance at its second terminal 154 which matches (i.e. identically or nearly identically) the impedance of the first and second power combiners 138 , 144 . As such, no additional appreciable impedance transformation occurs between the third and second nodes 136 , 134 (via the second power combiner 144 ) and between the second and first nodes 134 , 132 (via the first power combiner 138 ) of the constant impedance combiner 130 because the reactance of the power combiners 138 , 144 is minimal when the transformed impedance matches the power combiner impedances. As such, a constant impedance is maintained at the first, second and third nodes 132 , 134 , 136 .
For example, the load impedance may be 50 Ohms and the wideband impedance transformer 150 may be shaped to transform the 50 Ohm load impedance to 20 Ohms at the third node 136 of the constant impedance combiner 130 . Each of the power combiners 138 , 144 may be 20 Ohm ¼λ (quarter wavelength) transmission lines. As such, the power combiners 138 , 144 provide no further impedance transformation and the same 20 Ohm transformed impedance is maintained at the third, second and first nodes 136 , 134 , 132 of the constant impedance combiner 130 . Hence the term ‘constant impedance combiner’. A single impedance transformation occurs between the load 160 and the third node 136 of the constant impedance combiner 130 , and no further impedance transformation occurs between nodes 136 , 134 and 132 , and the amplifier circuit 100 has an optimized impedance for correct load modulation at back off 2 (i.e. the main amplifier is on, and the first and second peaking amplifiers are off), back off 1 (i.e. the main and peaking 1 amplifier are on, and the second peaking amplifier is off) and full power (i.e. all amplifiers are on).
As shown in FIG. 1 , the output of each amplifier 100 , 110 , 120 may be connected to the respective node 132 , 134 , 136 of the constant impedance combiner 130 via a corresponding output matching device 102 , 112 , 122 . Each output matching device 102 , 112 , 122 provides further impedance transformation between the specific transformed impedance presented at the three nodes 132 , 134 , 136 of the constant impedance combiner 130 and the corresponding amplifier output. Returning to the 50 Ohm load impedance example given above, the main amplifier 100 has an 11.1 Ohm load impedance at its output and the first peaking amplifier 110 may have an 18 Ohm output impedance after its output matching device 112 and the second peaking amplifier 120 may have a 50 Ohm output impedance after its output matching device 122 . The respective output matching devices 102 , 112 , 122 provide the desired impedance transformation between the transformed impedance presented at the three nodes 132 , 134 , 136 of the constant impedance combiner 130 and the corresponding amplifier output impedance.
FIG. 2 illustrates another embodiment of a three way wideband Doherty amplifier circuit. The circuit of FIG. 2 is similar to the circuit of FIG. 1 , except there is no output matching device ( 102 ) connecting the output of the main amplifier 100 to the first node 132 of the constant impedance combiner 130 . Instead, the output of the main amplifier 100 is directly connected to the first node 132 . According to this embodiment, the main amplifier 100 has the same impedance as that of the first power combiner 138 when the main amplifier 100 operates in the high impedance state (i.e. when the peaking amplifiers are turned off). Again returning to the 50 Ohm load impedance example given above, the 11.1 Ohm output impedance of the main amplifier 100 transforms to 20 Ohms (1.8× transformation factor) in the high impedance state which matches the 20 Ohm impedance present at the first node 132 of the constant impedance combiner 130 . Accordingly, no further impedance transformation is needed between the first node 132 of the constant impedance combiner 130 and the main amplifier output in the high impedance (load modulated) state.
FIG. 3 illustrates yet another embodiment of a three way wideband Doherty amplifier circuit. The circuit of FIG. 3 is similar to the circuit of FIG. 2 , except the parasitic output capacitance which for a MOS device is drain-to-source capacitance (schematically illustrated as capacitor Cds in FIG. 3 ) of the main amplifier 100 and the parasitic inductance (schematically illustrated as inductor Lseries in FIG. 3 ) associated with connecting the main amplifier output to the first node 132 of the constant impedance combiner 130 are absorbed into the impedance of the first power combiner 138 of the constant impedance combiner 130 . According to this embodiment, the main amplifier impedance matches that of the first power combiner 138 as viewed from the first node 132 of the constant impedance combiner 130 when the main amplifier 100 operates in the high impedance load modulated state (i.e. when the peaking amplifiers are turned off).
FIG. 4 illustrates still another embodiment of a three way wideband Doherty amplifier circuit. The circuit of FIG. 4 is similar to the circuit of FIG. 1 , except the impedance transformer 170 of the constant impedance combiner 130 is a ¼λ transmission line instead of a wideband (tapered) impedance transformer ( 150 ). According to this embodiment, the ¼λ transmission line 170 connects the load 160 to the third node 136 of the constant impedance combiner 130 and transforms the load impedance at its first terminal 172 to a transformed impedance at its second terminal 174 so that the transformed impedance at the third node 136 matches the impedance of the first and second power combiners 138 , 144 . Once again returning to the 50 Ohm load impedance example given above, both power combiners 138 , 144 may have a 20 Ohm impedance and the ¼λ transmission line 170 which connects the 50 Ohm load 160 to the third node 136 of the constant impedance combiner 130 may have an impedance of 31 Ohms. Accordingly, only a single impedance transformation is performed by the constant impedance combiner 130 . In yet another embodiment, the impedance transformer 170 can be two transmission lines connected in series or a lumped L (inductive) or a lumped C (capacitive) structure. Yet other types of impedance transformers may be used.
FIG. 5 illustrates an embodiment of a three way wideband Doherty amplifier circuit where the constant impedance combiner 130 has no impedance transformer. Instead, each power combiner 138 , 144 has an impedance with matches the load impedance. According to this embodiment, the constant impedance combiner 130 provides no impedance transformation and the impedance at nodes 132 , 134 and 136 of the combiner 130 corresponds to the load impedance in each case.
Specific exemplary impedance values for the different amplifier circuit components have been described herein for illustrative purposes only. These specific examples are not intended to limit the scope of the claims in any way unless explicitly claimed. For example, load impedances other than 50 Ohms may also be considered such as 75 Ohms, etc. The components of the constant impedance combiner can be sized accordingly to ensure only a single impedance transformation is performed by the constant impedance combiner. This also applies for the specific amplifier impedance values expressed herein.
Terms such as “same”, “match” and “matches” as used herein are intended to mean identical, nearly identical or approximately so that some reasonable amount of variation is contemplated without departing from the spirit of the invention. The term “constant” means not changing or varying, or changing or varying slightly again so that some reasonable amount of variation is contemplated without departing from the spirit of the invention. Further, terms such as “first”, “second”, and the like, are used to describe various elements, regions, sections, etc. and are also not intended to be limiting. Like terms refer to like elements throughout the description.
As used herein, the terms “having”, “containing”, “including”, “comprising” and the like are open ended terms that indicate the presence of stated elements or features, but do not preclude additional elements or features. The articles “a”, “an” and “the” are intended to include the plural as well as the singular, unless the context clearly indicates otherwise.
It is to be understood that the features of the various embodiments described herein may be combined with each other, unless specifically noted otherwise.
Although specific embodiments have been illustrated and described herein, it will be appreciated by those of ordinary skill in the art that a variety of alternate and/or equivalent implementations may be substituted for the specific embodiments shown and described without departing from the scope of the present invention. This application is intended to cover any adaptations or variations of the specific embodiments discussed herein. Therefore, it is intended that this invention be limited only by the claims and the equivalents thereof. | An amplifier circuit includes a first amplifier operable to turn on at a first power level, a second amplifier operable to turn on at a second power level below the first power level and a third amplifier operable to turn on at all power levels. A first power combiner is operable to combine an output of the third amplifier with an output of the second amplifier at a first power combining node to form a first combined amplifier output. A second power combiner is operable to combine the first combined amplifier output with an output of the first amplifier at a second power combining node to form a second combined amplifier output. An impedance transformer is operable to transform a load impedance of the amplifier circuit to a transformed impedance at the second power combining node, the transformed impedance matching an impedance of the first and second power combiners. | 7 |
RELATED APPLICATIONS
[0001] This application is a continuation of U.S. patent application Ser. No. 09/619,820, filed Jul. 20, 2000, which claims the priority benefit under 35 U.S.C. §119 of prior Finnish Application No. 991628, filed Jul. 20, 1999.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to the removal of substances contained in gases, such as gases flowing at low pressure. In particular, the present invention concerns a method and an apparatus for removing unreacted reactants and vapor phase precursors present in gases removed from vapor phase reactors.
[0004] 2. Description of the Related Art
[0005] In the atomic layer deposition method (ALD), the substrate is typically located in a reaction space, wherein it is subjected to alternately repeated surface reactions of at least two different reactants. Commercially available technology is supplied by ASM Microchemistry Oy, Espoo Finland under the trademark ALCVD™. According to the method, the reactants are admitted repetitively and alternately one reactant at a time from its own source in the form of vapor-phase pulses in the reaction space. Here, the vapor-phase reactants are allowed to react with the substrate surface for the purpose of forming a solid-state thin film on the substrate, particularly for use in the semiconductor arts.
[0006] While the method is most appropriately suited for producing so-called compound thin films, using as the reactants starting materials or precursors that contain component elements of the desired compound thin-film, it may also be applied to growing elemental thin films. Of compound films typically used in the art, reference can be made to ZnS films employed in electroluminescent displays, whereby such films are grown on a glass substrate using zinc sulfide and hydrogen sulfide as the reactants in the growth process. Of elemental thin films, reference can be made to silicon thin films.
[0007] An ALD apparatus comprises a reaction space into which the substrate can be placed, and at least two reactant sources from which the reactants used in the thin-film growth process can be fed in the form of vapor-phase pulses into the reaction space. The sources are connected to the reaction space via reactant inflow channels. Outflow channels (pumping lines) are attached to a pump and connected to the reaction space for removing the gaseous reaction products of the thin-film growth process, as well as the excess reactants in vapor phase.
[0008] The waste, i.e., the non-reacted reactants removed and discharged from the reaction space, is a serious problem for ALD processing. When it enters the pumping line and the pump, the waste gives rise to tedious cleaning and, in the worst case, the pump will rapidly be worn out.
[0009] Filtering of the gases and/or contacting of the gases with absorbents gives some help but both methods have been shown to be unsatisfactory in the long run. Building expensive heated pumping lines in order to move the waste though the pump does not help, because the problematic waste does not comprise superfluous amounts of separate precursors, such as water, titanium chloride or aluminum chloride, that can easily be pumped as separate materials. The problem arises when the materials are reacting, forming by-products having a lower vapor pressure, inside the pumping line. The problem is especially relevant when the reactants react with each other at temperatures lower than the intended process temperature, causing improper reactions. At those temperatures, oxychlorides might form in exhaust lines as a by-product of exemplary metal oxide deposition processes using metal chlorides as one of the ALD precursors. These by-products form a high volume powder. Typically this kind of reaction happens inside the pumping line between the reaction zone and the colder parts of the pumping line. Another problem occurs when precursors with a high vapor pressure at room temperature reach the pump sequentially at temperatures suitable for film growth. This might lead to a film material build-up on the surfaces of the pump. The material build-up can be very abrasive. This is a specific problem with heated pumping lines and hot dry pumps. This will cause the filling of tight tolerances and due to that the parts will contact each other and pump will crash. A third problem is the reactions between condensed portions of the previous reaction component and the vapor of the following pulse in the pumping line. This will cause CVD-type material growth and significant powder propagation.
[0010] As mentioned above, different solutions based on filtering and/or chemical treatment of the reaction waste have been tried for decades in process fore-lines, with more or less poor results. Formed by-products and powder tend to block the filters and due to the low process pressure the gas flow is too weak to keep the mesh of the filter open. The blocked filter will cause an additional pressure drop and therefore cause changes in the material flow from the source. Also, the process pressure and the speed of the gases will change. Attempts have been made to use cyclones and rotating peelers to remove the by-products from the mesh. By these means, some of the solid waste can be removed, but still the precursors with high vapor pressure will reach the pump and form by-products there.
[0011] Finnish Patent No. 84980 (Planar International Oy) discloses a system consisting of a condensation chamber, where the gas stream is slowed down and where a big part of the waste is condensed. Before entering the filter unit, extra water is injected into the filter housing to increase the by-products' particle size in order to prevent blockage of the filter mesh before the waste is removed by a rotating peeler system. Although this apparatus represents a clear improvement of the state of the art, it is still not completely satisfactory.
SUMMARY OF THE INVENTION
[0012] It is an aim of the present invention to eliminate the problem of the prior art and to provide a simple and reliable technical solution for removing waste from the reaction zone of an ALD reactor.
[0013] The present invention is based on the concept of processing all of the extra precursor material of the pulse dose, to form the end product, before the precursors are discharged from the reactor or the reaction zone. Thereby, the volume of the waste can be greatly reduced. The postprocessing of the precursor excess stemming from the ALD process is carried out by placing a sacrificial material with a high surface area (typically porous) in the reaction zone, which is swept by the precursors during their travel to the outlet of the reaction chamber. Alternatively, the material with high surface area can be placed in a separate heated vessel, outside the reaction zone but upstream of the discharge pump. The material with a high surface area is, however, in both embodiments kept essentially the growth conditions (for example, same pressure and temperature) as the reaction zone to ensure growth of a reaction product on the surface thereof. As a result, the material with a high surface area traps the remaining end product on its surface, thereby reducing the amount of reactant reaching the pump.
[0014] The present apparatus includes a reaction zone arranged downstream from (i.e., after) the reaction process, comprising a material with a high surface area and maintainable at essentially the same conditions as those prevailing during the gas phase reaction process. The reaction zone further includes gas flow channels for feeding gases discharged from the gas phase reaction process into the material with a high surface area and discharge gas channels for discharging gas from the material with a high surface area.
[0015] Considerable advantages are obtained with the present invention. Thus, the material with a high surface area will trap on its surface the end product of the reaction of the excess gaseous reactants. The surface area of the trap is generally large, on an average about 10 m 2 /g to 1000 m 2 /g; for example it can have the surface area on the same order as that of a soccer stadium. The trap can be in use for several runs before it is cleaned or replaced with a new one. The pump connected to the reaction space has only to cope with materials in gaseous form because mostly non-reactive gaseous by-products from the process reach the pump. “Non-reactive,” as used herein, refers to species other than the intended ALD reactants. The solid thin film product is substantially captured in the reactant trap; this will considerably reduce wear of the equipment.
[0016] The present invention is generally applicable to any gaseous reactants. It is particularly advantageous for reactions that form corrosive or otherwise harmful side products during the reaction of the gaseous reactants. Thus, a preferred embodiment is for dealing with the waste generated in a vapor phase reaction using chloride-containing reactants such as aluminum chloride, which are reacted with water to produce a metal oxide. The present invention is preferably used for ALD, but it can also be used for treating exhaust from conventional CVD processing or electron beam sputtering and any other gas phase processes in which the discharged gaseous reactants may react with each other downstream of the actual reaction zone housing the substrate. In the following description, the invention will, however, be described with particular reference to an ALD embodiment.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] Next the invention will be examined in more detail with reference to the attached drawings depicting a number of preferred embodiments.
[0018] [0018]FIGS. 1 a and 1 b are schematic top plan (FIG. 1 a ) and side elevational (FIG. 1 b ) views of a reactant trap comprising porous plates inside a suction box of an ALD reactor, constructed in accordance with a first preferred embodiment.
[0019] [0019]FIGS. 2 a and 2 b are schematic top plan (FIG. 2 a ) and side elevational (FIG. 2 b ) views of a reactant trap, constructed in accordance with a second preferred embodiment of the present invention, having an arrangement of plates inside a separate postreactor connected to the suction box of an ALD reactor.
[0020] [0020]FIGS. 3 a and 3 b are views corresponding to FIGS. 2 a and 2 b , with the plates replaced by glass wool cartridges, in accordance with a third embodiment.
[0021] [0021]FIGS. 4 a and 4 b are schematic cross-sections of a cartridge filled with glass wool (FIG. 4 a ) and a cartridge filled with graphite foil (FIG. 4 b ).
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0022] Generally, the present invention is based on the idea of placing—between the substrates of an ALD reactor and the pump—a material with a high surface area, which forms a postreaction substrate for the discharged superfluous gas phase reactants leaving the actual reaction zone. It is preferred that the surface of the porous material is so large that all of the superfluous material can adsorb upon surfaces of the reactant trap and then be converted into the corresponding final compound when the next reactant pulse enters, according to the principle of ALD (Atomic Layer Deposition).
[0023] The postreaction reactant trap can be placed inside the vacuum vessel, within the hot reaction zone, or it can be formed as a separate chamber between the process chamber (or primary reaction zone) and the pump; even the space of the suction box can be used as a holder for the trapping receptacles.
[0024] The following example relates to growing an aluminum oxide layer with the ALD technique. In a 3,000 cycle Al 2 O 3 process, 100 g of AlCl 3 and 100 g of H 2 O is consumed. Roughly one-third (60 g) of the reactants ends up as Al 2 O 3 , of which aluminum represents 30 g and oxygen represents 30 g. Two-thirds of the consumed reactant mass will form HCl in an amount of 140 g. One-third, equaling 20 g of the precursors, is used in the thin film product grown on the substrates; the remaining two-thirds (40 g) of Al 2 O 3 is preferably captured by the trap. This means roughly 40 g of solids in the trap per run. The deposited Al 2 O 3 in each run has a thickness of 150 nm, which corresponds to a film growth of 15 μm on the trap surface after 100 runs. By selecting the pore size and path length so that there is essentially no pressure drop over the trap and that any reaction products can be purged away before the next pulse enters the trap, the thin film grown in the trap will not restrict the gas flow.
[0025] It is particularly desirable to avoid formation of large molecules, such as oxychlorides, that would occupy a large volume and block the flow paths of the material with a high surface area.
[0026] According to the preferred embodiment, the sacrificial trapping block(s) or plates can be made of any suitable material with a high surface area, preferably porous (e.g., graphite, such as porous graphite foils, alumina (Al 2 O 3 ) or silica). Various ceramic materials, e.g., honeycomb ceramics, and other mineral materials such as glass wool, can also be used. Reticulated Vitreous Carbon is another example of a suitable material. The material should withstand the physical and chemical conditions of the reaction zone (reaction temperature and pressure; it should be chemically inert to the reactants but able to adsorb the ALD reactants). Further it should have a large surface so as to allow for a reaction of the gaseous reactants on the surface thereof in order to form the reaction product (such as aluminum oxide). Generally, the surface area of the trap material is 10 m 2 /g to 2000 m 2 /g, in particular about 100 m 2 /g to 1500 m 2 /g. One alternative is to have a porous ceramic material with a roughened surface which will allow for penetration of the gaseous reactants into the material, leaving by-products such as hydrochloric acid, on the surface so that it can be more easily purged away. The pores of the porous material should not be too narrow and deep so that the (non-reacted) residues of the previous pulse cannot be purged away before the next pulse is introduced. Material having an average pore size on the order of about 10 to 100 m is preferred.
[0027] It is also preferred that the surface of the reactant trap is large enough that the same trap material can be used for the growth of several batches of thin-film elements. As discussed above, the excess of reactant is generally 4 to 5 times the amount needed for covering the surface of the substrates with a thin film of desired thickness. Therefore, the surface area of the material is preferably at least 4 to 5 times larger than the total surface of the substrates. More preferably, the surface should be much larger, e.g., so as to allow for uninterrupted operation for a whole day, depending on the production capacity of the reactor.
[0028] There should be no substantial pressure difference over the high surface area of the reactant trap. For this reason, the material with a high surface area is preferably provided with flow paths which allow for free flow of the gases while offering the gas phase components enough surface for surface reactions. Various ways of achieving free flow paths to achieve minimal pressure drops are depicted in the embodiments of the drawings.
[0029] Turning now to the attached drawings, it will be noted that in FIGS. 1 a and 1 b , the reactant trap 1 (which can also be called an “afterburner”, a “downstream reaction space” or a “secondary reaction space”) is preferably placed below the actual reaction space 2 (or “primary reaction space”) of the ALD reactor. The reactant trap comprises a plurality of trapping plates 3 , which are placed in parallel relationship inside the suction box 4 of the reactor. Between the trapping plates 3 there are flow channels formed to allow for the continued flow of the gases to the pump (not shown). When the trapping plates are made of a suitable material with a high surface area, the reactant gases will diffuse inside the plates and deposit the reactants due to surface reactions similar to those reactions taking place in the reaction space above, e.g., between glass substrates and the reactant vapors.
[0030] By arranging the reactant trap immediately after or under the reaction zone, a free flow path or channel for the excess reactants can easily be arranged. Likewise, it is simple to carry out the discharge of the gas from the reactant trap because it is subject to the same reduced pressure, produced by the discharge pump, as the rest of the reactor.
[0031] After each reactant pulse fed in to the reaction space and, consequently, into the reactant trap 1 , the reaction space is generally purged with an inert or inactive gas, such as nitrogen. Then a subsequent gas phase pulse is fed into the reaction space (and thence into the reactant trap). Thus, in the example of an ALD Al 2 O 3 process, an aluminum chloride pulse is usually followed by a water vapor pulse in the reaction space to convert the aluminum chloride into aluminum oxide. The same reaction takes place on the surface of the substrates placed in the ALD reactor and in the reactant trap. By placing the reactant trap inside the same reaction space or reaction box as the substrates, the necessary temperature and pressure levels for achieving an ALD (Atomic Layer Deposition) reaction on the surface of the trapping material are automatically obtained. The reactants will form the same end product, e.g., ATO or Al 2 O 3 , on the surface of the trap as on the substrates.
[0032] The embodiment of FIGS. 2 a and 2 b is similar to that of FIGS. 1 a and 1 b , with the exception that the reactant trap 11 is placed in a separate vessel 13 kept at the same reaction conditions as the reactor. The trapping plates 12 are arranged in a similar fashion as the plates in FIGS. 1 a and 1 b , but the flow channel is arranged to provide a serpentine path. In this way, a sufficient contact time with the trapping plates can be provided. The reactant trap vessel is attached to the suction box of an ALD reactor with a conduit.
[0033] The embodiment of FIGS. 3 a and 3 b corresponds to a combination of the embodiment of FIGS. 1 and 2, in the sense that the trapping plates 22 are placed in a separate vessel 23 , but the plates are fixed in parallel relationship with flow paths between them. The plates 22 of the illustrated embodiment are made of glass wool.
[0034] [0034]FIGS. 4 a and 4 b show replaceable cartridges 32 made of material with a high surface area, such as glass wool (FIG. 4 a ) with flow paths 33 formed in said material. Similar flow paths 35 are arranged between adjacent layers of a graphite foil 34 wound in a spiral fashion in FIG. 4 b . The layers are preferably arranged at a distance of about 0.1 mm to 10 mm, preferably about 0.5 mm to 5 mm from each other.
[0035] The traps of FIGS. 4 a and 4 b are preferably made of an inexpensive material, such that they can be thrown away after an effective period of use.
[0036] In the embodiments of all of the FIGS. 2 to 4 , the operation of the precursor trap is quite similar to that described in connection with the embodiment of FIGS. 1 a and 1 b . The material with a high surface area is maintained at a temperature similar to that of the actual reaction zone (i.e., depending on the precursors and the substrate, preferably about a 50° C. to 600° C., more preferably about 200° C. to 500° C.). The pressure can be atmospheric, but it is generally preferred to work at reduced pressure of about 1 mbar to 100 mbar (i.e., “low pressure”). The inactive gas used for purging preferably comprises nitrogen or a noble gas such as argon.
[0037] Although the above embodiments have particular utility in the preparation of thin-film structures on all kinds of surfaces for semiconductor and flat panel devices, it should be noted that it can be applied to any chemical gas vapor deposition reactor (e.g., CVD or ALD), including the preparation of catalysts using thin film coatings. | The present invention concerns a method and an apparatus for removing substances from gases discharged from gas phase reactors. In particular, the invention provides a method for removing substances contained in gases discharged from an ALD reaction process, comprising contacting the gases with a “sacrificial” material having a high surface area kept at essentially the same conditions as those prevailing during the gas phase reaction process. The sacrificial material is thus subjected to surface reactions with the substances contained in the gases to form a reaction product on the surface of the sacrificial material and to remove the substances from the gases. The present invention diminishes the amount of waste produced in the gas phase process and reduces wear on the equipment. | 1 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims the benefit of and priority to U.S. Provisional Application Ser. No. 60/422,468, filed on Oct. 30, 2002, the disclosure of which is incorporated herein by reference.
FIELD OF THE INVENTION
[0002] This invention relates generally to semiconductor substrates and specifically to formation of dielectric layers on semiconductor substrates.
BACKGROUND OF THE INVENTION
[0003] The increasing operating speeds and computing power of microelectronic devices have recently given rise to the need for an increase in the complexity and functionality of the semiconductor structures that are used as the starting substrates in these microelectronic devices. Such “virtual substrates” based on silicon and germanium provide a platform for new generations of very large scale integration (“VLSI”) devices. that exhibit enhanced performance when compared to devices fabricated on bulk Si substrates. Specifically, new technological advances enable formation of heterostructures using silicon-germanium alloys (hereinafter referred to as “SiGe” or “Si 1-x Ge x ”) to further increase performance of the semiconductor devices by changing the atomic structure of Si to increase electron and hole mobility.
[0004] The important component of a SiGe virtual substrate is a layer of SiGe heterostructure that has been relaxed to its equilibrium lattice constant (i.e., one that is larger than that of Si). This relaxed SiGe layer can be directly applied to a Si substrate (e.g., by wafer bonding or direct epitaxy), or atop a relaxed graded SiGe buffer layer in which the lattice constant of the SiGe material has been increased gradually over the thickness of the layer. The SiGe virtual substrate may also incorporate buried insulating layers, in the manner of a silicon-on-insulator (SOI) wafer. To fabricate high-performance devices on these platforms, thin strained layers of semiconductors, such as Si, Ge, or SiGe, are grown on the relaxed SiGe virtual substrates. The resulting biaxial tensile or compressive strain alters the carrier mobilities in the layers, enabling the fabrication of high-speed and/or low-power-consumption devices. The percentage of Ge in SiGe and the method of deposition can have a dramatic effect on the characteristics of the strained Si layer. U.S. Pat. No. 5,442,205, “Semiconductor Heterostructure Devices with Strained Semiconductor Layers,” incorporated herein by reference, describes one such method of producing a strained Si device structure.
[0005] An approach to epitaxially growing a relaxed SiGe layer on bulk Si is discussed in International Application Publication No. WO 01/22482, entitled “Method of Producing Relaxed Silicon Germanium Layers” and incorporated herein by reference. The method includes providing a monocrystalline Si substrate, and then epitaxially growing a graded Si 1-x Ge x layer with increasing Ge concentration at a gradient of less than 25% Ge per micrometer to a final Ge composition in the range of 0.1<x<1, using a source gas of Ge x H y C z for the Ge component, on the Si substrate at a temperature in excess of 850° C., and then epitaxially growing a semiconductor material on the graded layer.
[0006] Another method of epitaxially growing a relaxed SiGe layer on bulk Si is discussed in a paper entitled, “Low Energy plasma enhanced chemical vapor deposition,” by M. Kummer et al. ( Mat. Sci. & Eng . B89, 2002, pp. 288-95) and incorporated herein by reference, in which a method of low-energy plasma-enhanced chemical vapor deposition (LEPECVD) is disclosed. This method allows the formation of a SiGe layer on bulk Si at high growth rates (0.6 μm per minute) and low temperatures (500-750° C.).
[0007] To grow a high-quality, thin, epitaxial strained Si layer on a graded SiGe layer, the SiGe layer is, preferably, planarized or smoothed to reduce the surface toughness in the final strained Si substrate. Current methods of chemical mechanical polishing (“CMP”) are typically used to decrease roughness and improve the planarity of surfaces in semiconductor fabrication processes. U.S. Pat. No. 6,107,653, “Controlling Threading Dislocations in Ge on Si Using Graded GeSi Layers and Planarization,” incorporated herein by reference, describes how planarization can be used to improve the quality of SiGe graded layers.
[0008] One technique suitable for fabricating strained Si wafers can include the following steps:
1. Providing a silicon substrate that has been edge-polished; 2 . Epitaxially depositing a relaxed graded SiGe buffer layer to a final Ge composition on the silicon substrate; 3. Epitaxally depositing a relaxed Si 1-x Ge x cap layer having a constant composition on the graded SiGe buffer layer; 4. Planarizing or smoothing the Si 1-x Ge x cap layer and/or the relaxed graded SiGe buffer layer by, e.g., CMP; 5. Epitaxially depositing a relaxed Si 1-x Ge x regrowth layer having a constant composition on the planatized surface of the Si 1-x Ge x cap layer; and 6. Epitaxially depositing a strained silicon layer on the Si 1-x Ge x regrowth layer.
[0015] By introducing strain gradually over a series of low lattice mismatch interfaces, compositionally graded layers, as recited in step 2 above, offer a viable route toward integration of heavily lattice-mismatched monocrystalline semiconductor layers on a common substrate, offering a route towards increased functionality through monolithic integration. Utilizing both strain and bandgap engineering, modulation-doped FETs (MODFETs) and metal-oxide-semiconductor FETs (MOSFETs) may be tailored for enhanced-performance analog or digital applications. However, because these devices are fabricated on Si/SiGe virtual substrates rather than on the Si substrates commonly utilized for complementary MOS (CMOS) technologies, they present new processing challenges.
[0016] For example, because thin, near-surface, strained heteroepitaxial layers constitute critical parts of devices formed on relaxed SiGe virtual substrates the processing windows for such structures are limited. Specifically, it is desirable to avoid the consumption of these near-surface strained layers during processing. Traditional silicon-based CMOS process flows, therefore, may not be suitable for these layers because conventional CMOS processes typically result in the consumption of a large portion of surface substrate material. This consumption is primarily due to thermal oxidation steps. For example, thin thermally grown oxides are commonly used as screening layers (also called “passivation layers”) during ion implantation steps. These passivation layers also serve to discourage out-diffusion of dopants during subsequent thermal anneals. Also, thermally grown pad oxides are used as a stress-mediating underlayer beneath a silicon nitride trench mask layer for shallow trench isolation (STI formation. These thermal oxidation steps, however, typically remove a total of several hundred angstroms (Å) of surface Si material. Accordingly, thermal oxidation is not desirable when processing wafers that incorporate thin surface layers formed on SiGe virtual substrates, where a final minimum thickness of 50 Å of the thin strained layer (from a starting thickness of, e.g., 50-200 Å) needs to be available for device channels.
[0017] Thus, there is a need in the art for method for forming a semiconductor structure that minimizes consumption of the material proximate to the top surface of the substrate.
SUMMARY OF THE INVENTION
[0018] Accordingly, it is an object of the present invention to provide a method for forming a semiconductor structure having a strained semiconductor layer that overcomes the limitations of known methods. Specifically, in various embodiments of the invention, methods of providing dielectric layers, such as, for example, oxide layers, which avoid consuming unacceptably large amounts of the surface material in Si/SiGe heterostructure-based wafers are proposed to replace or supplement various intermediate CMOS thermal oxidation steps known in the art. First, by using oxide deposition methods such as chemical vapor deposition (CVD), arbitrarily thick dielectric layers may be formed with little or no consumption of surface silicon. These layers, for example, oxide layers, such as a screening oxide and pad oxide layers, are formed by deposition onto, rather than reaction with and consumption of the surface layer. Alternatively, oxide deposition is preceded by a thermal oxidation step of short duration, e.g., rapid thermal oxidation. Here, the short thermal oxidation consumes little surface Si, and the Si/oxide interface is of high quality. The oxide may then be thickened to a desired final thickness by deposition. Furthermore, the thin thermal oxide may act as a barrier layer to prevent contamination associated with subsequent oxide deposition.
[0019] In general, in one aspect, a method for forming a semiconductor structure includes forming a strained semiconductor layer over a substrate and depositing a screening layer over at least a portion of a top surface of the strained semiconductor layer. In various embodiments of the invention, the thickness of the strained semiconductor is substantially unchanged following the deposition of the screening layer. In one embodiment, the strained semiconductor layer is tensilely strained, and includes, for example, a tensilely strained silicon or tensilely strained silicon-germanium alloy. In another embodiment, the strained semiconductor layer is compressively strained, and includes, for example, compressively strained germanium or compressively strained silicon-germanium alloy. The strained layer may have a thickness ranging from about 50 Å to about 1000 Å, for example, not exceeding about 300 Å. In a particular embodiment, the thickness of the strained layer does not exceed about 200 Å.
[0020] The substrate may include at least one of silicon and germanium. In one embodiment, the substrate includes an insulating layer disposed underneath the strained semiconductor layer. In another embodiment, the substrate includes a relaxed semiconductor layer disposed underneath the strained semiconductor layer. In various versions of this embodiment, the substrate further includes a compositionally graded layer disposed underneath the relaxed semiconductor layer. The graded layer may include at least one of a group II, a group III, a group IV, a group V, and a group VI element, for example, at least one of silicon and germanium. The graded layer can be graded to a concentration of greater than about 10% germanium and may have thickness ranging from about 0.5 μm to about 10.0 μm.
[0021] The step of depositing the screening layer may include chemical vapor deposition. In one embodiment, the screening layer includes an oxide layer, for example, selected from the group consisting of silicon dioxide, silicon oxynitride, silicon germanium oxide, or germanium oxide. The screening layer may have thickness ranging from about 20 Å to about 300 Å.
[0022] In various embodiments, the method further includes introducing dopants into the semiconductor structure, wherein the screening layer affects the introduction of dopants into at least a portion of the structure by at least one of scattering dopants and reducing energy of the dopants. The method may also include subjecting the structure to a thermal anneal, wherein the screening layer hinders out-diffusion of the dopants from at least a portion of the substrate.
[0023] In one embodiment, prior to depositing a screening layer, an oxide layer is grown over the portion of the top surface of the strained semiconductor layer by, for example, a rapid thermal oxidation. Thickness of the oxide layer may range from about 5 Å to about 30 Å.
[0024] In general, in another aspect, a method for forming a structure includes forming a strained semiconductor layer over a substrate, depositing a pad oxide layer over at least a portion of a top surface of the strained semiconductor layer; and forming a masking layer over the pad oxide layer. The pad oxide layer substantially inhibits formation of stress-induced defects in the strained semiconductor layer. The masking layer may include silicon nitride.
[0025] In one embodiment, prior to depositing a pad oxide layer, an oxide layer is grown over the portion of the top surface of the strained semiconductor layer, for example, by a rapid thermal oxidation. The thickness of the oxide layer may range from about 5 Å to about 30 Å.
[0026] In various embodiments of this aspect of the invention, the substrate includes at least one of silicon and germanium. In one embodiment, the substrate includes an insulating layer disposed underneath the strained semiconductor layer. In another embodiment, the substrate includes a relaxed semiconductor layer disposed underneath the strained semiconductor layer. In various versions of this embodiment, the substrate further includes a compositionally graded layer disposed underneath the relaxed semiconductor layer. The graded layer may include at least one of a group II, a group III, a group IV, a group V, and a group VI element, for example, at least one of silicon and germanium. The graded layer can be graded to a concentration of greater than about 10% germanium and may have thickness ranging from about 0.5 μm to about 10.0 μm.
[0027] The strained semiconductor layer may be tensilely strained, and may include, for example, a tensilely strained silicon or tensilely strained silicon-germanium alloy. In another embodiment, the strained semiconductor layer is compressively strained, and includes, for example, compressively strained germanium or compressively strained silicon-germanium alloy. The strained layer may have a thickness ranging from about 50 Å to about 1000 Å, for example, not exceeding about 300 Å. In a particular embodiment, the thickness of the strained layer does not exceed about 200 Å.
[0028] In various embodiments, thickness of the strained semiconductor is substantially unchanged following the deposition of the pad oxide layer. The pad oxide layer can be deposited by, for example, chemical vapor deposition. The pad oxide layer may include silicon dioxide, silicon oxynitride, silicon germanium oxide, or germanium oxide, and have thickness ranging from about 50 Å to about 500 Å.
BRIEF DESCRIPTION OF THE DRAWINGS
[0029] In the drawings, like reference characters generally refer to the same parts throughout the different views. Also, the drawings are not necessarily to scale, emphasis instead generally being placed upon illustrating the principles of the invention. In the following description, various embodiments of the present invention are described with reference to the following drawings, in which:
[0030] FIGS. 1A-1D depict schematic cross-sectional views of several substrates suitable for fabrication of semiconductor structures according to the embodiments of the invention; and
[0031] FIGS. 2A-2B depict schematic cross-sectional views of a semiconductor substrate having a screening layer formed thereon according to the embodiments of the invention.
[0032] FIGS. 3A-3B depict schematic cross-sectional views of a semiconductor substrate having a pad oxide layer formed thereon according to the embodiments of the invention.
DETAILED DESCRIPTION
[0033] In accordance with various embodiments of the present invention, layers deposited on semiconductor substrates replace traditionally grown layers, thereby reducing the consumption of substrate surface material. Various features of the invention are well suited to applications utilizing MOS devices that include, for example, Si, Si 1-x Ge x and/or Ge layers in and/or on a substrate. The term “MOS” is used herein to refer generally to semiconductor devices that include a conductive gate spaced at least by an insulating layer from a semiconducting channel layer. The terms “SiGe,” “Si 1-x Ge x ,” and “Si 1-y Ge y ” refer to silicon-germanium alloys.
[0034] Referring to FIG. 1A , which illustrates an epitaxial wafer 100 suitable to use with the present invention, several layers collectively indicated at 101 , including a strained layer 102 and a relaxed layer 104 , are disposed over a substrate 106 . The substrate 106 comprises a semiconductor, such as silicon, silicon deposited over an insulator, such as, for example, SiO 2 , or a silicon-germanium alloy. In one embodiment, the layers 101 are epitaxially grown over the substrate 106 . In this embodiment, the layers 101 and the substrate 106 may be referred to together as a “virtual substrate.”
[0035] The ensuing discussion focuses on a strained layer 102 that is tensilely strained, but it is understood that the strained layer 102 may be tensilely or compressively strained. The strained layer 102 has a lattice constant other than the equilibrium lattice constant of the material from which it is formed, and it may be tensilely or compressively strained; the relaxed layer 104 has a lattice constant equal to the equilibrium lattice constant of the material from which it is formed. The tensilely strained layer 102 shares an interface 108 with the relaxed layer 104 .
[0036] The substrate 106 and the relaxed layer 104 may be formed from various materials systems, including various combinations of group II, group III, group IV, group V, and group VI elements. For example, each of the substrate 106 and the relaxed layer 104 may include a III-V compound. The substrate 106 may include gallium arsenide (GaAs), and the relaxed layer 104 may include indium gallium arsenide (InGaAs) or aluminum gallium arsenide (AlGaAs). These examples are merely illustrative, and many other material systems are suitable.
[0037] In various embodiments, the relaxed layer 104 may include Si 1-x Ge x with a uniform composition, containing, for example, Ge in the range 0.1≦x≦0.9 and having a thickness T 1 of, e.g., 0.2-2 μm. In one particular embodiment, T 1 is about 1.5 μm.
[0038] The strained layer 102 may include a semiconductor such as at least one of a group II, a group III, a group IV, a group V, and a group VI element. The strained semiconductor layer 102 may include, for example, Si, Ge, SiGe, GaAs, indium phosphide (InP), and/or zinc selenide (ZnSe). In some embodiments, the strained semiconductor layer 102 may include approximately 100% Ge, and may be compressively strained. A strained semiconductor layer 102 comprising 100% Ge may be formed over, e.g., the relaxed layer 104 containing uniform Si 1-x Ge x having a Ge content of, for example, 50-90% (i.e., x=0.5-0.9), preferably 70% (i.e., x=0.7).
[0039] In various embodiments, tensilely strained layer 102 is formed of silicon. The tensilely strained layer 102 has a thickness T 2 of, for example, 50-1000 Å. In a particular embodiment, thickness T 2 is less than about 300 Å, preferably below 200 Å. In embodiments in which the strained layer 102 includes materials other than silicon, a thin silicon cap layer may be disposed over strained layer 102 . This silicon cap layer may have a thickness of, for example, between about 5 Å and about 50 Å.
[0040] The epitaxially grown layers 101 , including the relaxed layer 104 and strained layer 102 , can be grown in any suitable epitaxial deposition system, including, but not limited to, atmospheric-pressure CVD (APCVD), low- (or reduced-;) pressure CVD (LPCVD), ultra-high-vacuum CVD (UHVCVD), by molecular beam epitaxy (MBE), or by atomic layer deposition (ALD). The epitaxial growth system may be a single-wafer or multiple-wafer batch reactor. The growth system also may utilize low-energy plasma to enhance the layer growth kinetics.
[0041] Suitable CVD systems commonly used for volume epitaxy in manufacturing applications include, for example, EPI CENTURA single-wafer multi-chamber systems available from Applied Materials of Santa Clara, Calif., or EPSILON single-wafer epitaxial reactors available from ASM International based in Bilthoven, The Netherlands.
[0042] In the CVD process, obtaining epitaxial growth typically involves introducing a source gas into the chamber. The source gas may include at least one precursor gas and a carrier gas, such as, for example hydrogen. In those embodiments of the invention where the layers are formed from Si, silicon precursor gases such as, for example, silane, disilane, trisilane, or dichlorosilane DCS) trichlorosilane (TCS), or silicon tetrachloride may be used. Conversely, in those embodiments of the invention where the layers are formed from Ge, germanium precursor gases, such as, for example, germane (GeH 4 ), digermane, germanium tetrachloride, or dichlorogermane, or other Ge-containing precursors may be used. Finally, in the embodiments where the layers are formed from SiGe alloy, a combination of silicon and germanium precursor gases in various proportions is used.
[0043] In an embodiment in which the strained layer 102 contains substantially 100% Si, the strained layer 102 may be formed in a dedicated chamber of a deposition tool that is not exposed to Ge source gases, thereby avoiding cross-contamination and improving the quality of the interface 108 between the strained layer 102 and the relaxed layer 104 . Furthermore, the strained layer 102 may be formed from an isotopically pure silicon precursor(s). Isotopically pure Si has better thermal conductivity than conventional Si. Higher thermal conductivity may help dissipate heat from devices subsequently formed on the strained layer 102 , thereby maintaining the enhanced carrier mobilities provided by the strained layer 102 .
[0044] In various embodiments, relaxed layer 104 and/or strained layer 102 may be planarized or smoothed to improve the quality of subsequent wafer bonding. Planarization or smoothing may be accomplished by CMP or in situ epitaxy-based methods, for example, although other techniques are acceptable as well. Following planarization, the relaxed layer 104 may have a surface roughness less than 1 nm, and the strained layer 102 may have a surface roughness, e.g., less than 0.5 nanometer (nm) root mean square (RMS).
[0045] Referring to FIG. 1B , in another embodiment, an epitaxial wafer 200 amenable for use with the present invention may include layers in addition to those indicated in FIG. 1A . In this embodiment, several layers collectively indicated at 202 are disposed over a semiconductor substrate 204 formed from, e.g. silicon. The layers 202 may be epitaxially grown by, for example, APCVD, LPCVD, or UHVCVD. The layers 202 and the substrate 204 may be referred to together as a “virtual substrate.”
[0046] The layers 202 include a graded layer 206 having a thickness T 3 ranging from about 0.1 μm to about 10 μm, is disposed over substrate 204 . The relaxed layer 104 described above is disposed over the graded layer 206 .
[0047] In one embodiment, the graded layer 206 includes Si and Ge with a grading rate of, for, example, 10% Ge per μm of thickness, and a thickness ranging from about 2 μm to about 9 μm. In another embodiment, the graded layer 206 includes Si and Ge with a grading rate of, for example, over about 5% Ge per μm of thickness, and generally in the range of >5% Ge/μm to 100% Ge/μm, preferably between 5% Ge/μm and 50% Ge/μm, to a final Ge content of between about 10% to about 100% Ge. While the overall grading rate of the graded layer is generally defined as the ratio of total change in Ge content to the total thickness of the layer, a “local grading rate” within a portion of the graded layer may be different from the overall grading rate. For example, a graded layer including a 1 μm region graded from 0% Ge to 10% Ge (a local grading rate of 10% Ge/μm) and a 1 μm region graded from 10% Ge to 30% Ge (a local grading rate of 20% Ge/μm) will have an overall grading rate of 15% Ge/μm. Thus, a relaxed graded layer may not necessarily have a linear profile, but may comprise smaller regions having different local grading rates. In various embodiments, the graded layer 206 is grown, for example, at 600-1200° C. Higher growth temperatures, for example, exceeding 900° C. may be preferred to enable faster growth rates while minimizing the nucleation of threading dislocations. See, generally, U.S. Pat. No. 5,221,413, incorporated herein by reference in its entirety.
[0048] Still referring to FIG. 1B , in some embodiments, a compressively strained layer 208 including a semiconductor material is disposed over the relaxed layer 104 . In one embodiment, the compressively strained layer 208 includes group IV elements, such as Si 1-y Ge y , with a Ge content (y) higher than the Ge content (x) of the relaxed (Si 1-x Ge x ) cap layer, for example, in the range 0.25≦y≦1. The compressively strained layer 208 may contain, for example, 1-100% Ge, preferably over 40% Ge, and may have a thickness T 4 ranging from about 10 to about 500 angstroms (Å), preferably below 200 Å. In some embodiments, the compressively strained layer 208 includes at least one group III and one group V element, e.g., indium gallium arsenide, indium gallium phosphide, or gallium arsenide. In alternative embodiments, the compressively strained layer 160 includes at least one group II and one group VI element, e.g., zinc selenide, zinc sulfide, cadmium telluride, or mercury telluride.
[0049] Still referring to FIG. 1B , in one embodiment, the tensilely strained layer 102 is disposed over the compressively strained layer 208 , sharing an interface 210 therewith. In another embodiment, the compressively strained layer 208 may be disposed not under, but over the tensilely strained layer 102 . Alternatively, in yet another embodiment, there is no compressively strained layer 208 and instead the tensilely strained layer 102 is disposed over the relaxed layer 104 , sharing an interface therewith. In still another embodiment, a relaxed constant-composition regrowth layer (not shown) is disposed over the relaxed layer 104 , sharing an interface therewith, and a tensilely strained layer is disposed over the constant-composition regrowth layer, sharing an interface with that layer. The regrowth layer may, for example, include Si 1-x Ge x with a uniform composition, containing, e.g., 1-100% Ge and having a thickness of, for example, 0.01-2 μm.
[0050] In various embodiments, the substrate 206 with layers 202 disposed thereon has a threading dislocation density of 10 4 -10 5 cm −2 .
[0051] Referring to FIG. 1C , in yet another embodiment, an epitaxial wafer 300 amenable for use with the present invention is a strained-semiconductor-on-semiconductor SSOS substrate 302 , having a strained layer 102 disposed in contact with a crystalline semiconductor handle wafer. The handle wafer may include a bulk semiconductor material, such as silicon. The strain of the strained layer 102 is not induced by underlying handle wafer 310 , and is independent of any lattice mismatch between the strained layer 102 and the handle wafer 310 . In a particular embodiment, the strained layer 102 and the handle wafer 310 include the same semiconductor material, e.g., silicon. The handle wafer 310 may have a lattice constant equal to a lattice constant of the strained layer 102 in the absence of strain. The strained layer 102 may have a strain greater than approximately 10 −3 . The strained layer 102 may have been formed by epitaxy, and may have a thickness T2 ranging from approximately 20 Å to approximately 1000 Å, with a thickness uniformity of better than approximately ±10%. In various embodiments, the strained layer 102 may have a thickness uniformity of better than approximately ±5%. The strained layer 102 may have a surface roughness of less than 20 Å.
[0052] The SSOS substrate 302 may be formed, as described in U.S. Ser. Nos. 10/456,708, 10/456,103, 10/264,935, and 10/629,498, the entire disclosures of each of the four applications being incorporated herein by reference. The SSOS substrate formation process-may include the formation of the strained layer 102 over the substrate 106 as described above with reference to FIG. 1A . A cleave plane may be defined in, e.g., the relaxed layer 104 . The strained layer 102 may be bonded to the handle wafer 310 , and a split may be induced at the cleave plane. Portions of the relaxed layer 104 remaining on the strained layer 102 may be removed by, e.g., oxidation and/or wet etching.
[0053] Yet another epitaxial wafer suitable for use with the present invention is a strained-semiconductor-on-insulator (SSO) wafer 400 . Referring to FIG. 1D , a SSOI wafer 400 has the strained layer 102 disposed over an insulator, such as a dielectric layer 410 formed on a semiconductor substrate 402 . The SSOI wafer 400 may be formed by methods analogous to the methods described above in the formation of the SSOS wafer 300 . The dielectric layer 410 may include, for example, SiO 2 . In one embodiment, the dielectric layer 410 includes a material having a melting point (T m ) higher than a T m of pure SiO 2 , i.e., higher than 1700° C. Examples of such materials include silicon nitride (Si 3 N 4 ), aluminum oxide, and magnesium oxide. In another embodiment, the dielectric layer 410 includes a high-k material with a dielectric constant higher than that of SiO 2 , such as aluminum oxide (Al 2 O 3 ), hafnium oxide (HfO) or hafnium silicate (HfSiON or HfSiO 4 ). The semiconductor substrate 402 includes a semiconductor material such as, for example, Si, Ge, or SiGe. The strained layer 102 has a thickness T 2 ranging, for example, from about 50 to about 1000 Å, with a thickness uniformity of better than approximately ±5% and a surface roughness of less than approximately 20 Å. The dielectric layer 410 has a thickness T 5 selected from a range of, for example, 500-3000 Å. In an embodiment, the strained layer 102 includes approximately 100% Si or 100% Ge having one or more of the following material characteristics: misfit dislocation density of, e.g., 0-10 5 cm −1 ; a threading dislocation density of about 10-10 7 dislocations/cm 2 ; a surface roughness of approximately 0.01-1 nm RMS; and a thickness uniformity across the SOI substrate 400 of better than approximately ±10% of a mean desired thickness; and a thickness T 2 of less than approximately 200 Å. In an embodiment, the SSOI substrate 400 has a thickness uniformity of better than approximately ±5% of a mean desired thickness.
[0054] In one embodiment, the dielectric layer 410 has a T m greater than that of SiO 2 . During subsequent processing, e.g., MOSFET formation, SSOI substrate 400 may be subjected to high temperatures, i.e., up to 1100° C. High temperatures may result in the relaxation of strained layer 102 at an interface 430 between strained layer 102 and dielectric layer 410 . The use of dielectric layer with a T m greater than 1700° C. may help keep strained layer 102 from relaxing at the interface 430 between strained layer 102 and dielectric layer 410 when the SSOI substrate is subjected to high temperatures.
[0055] In one embodiment, the misfit dislocation density of the strained layer 102 may be lower than its initial misfit dislocation density. The initial dislocation density may be lowered by, for example, performing an etch of a top surface 440 of the strained layer 102 . This etch may be a wet etch, such as a standard microelectronics clean step such as an RCA SC1, i.e., hydrogen peroxide, ammonium hydroxide, and water (H 2 O 2 +NH 4 OH+H 2 O), which at, e.g., 80° C. may remove silicon.
[0056] Referring to FIG. 2A , in one embodiment of the invention, a screening layer 500 is formed over the strained layer 102 of the semiconductor wafer 550 . The wafer 550 can be any one of the wafers 100 , 200 , 300 , or 400 described above. The screening layer 500 may include an oxygen-containing dielectric layer, for example, an oxide layer, including, but not limited to, silicon dioxide (SiO), silicon oxynitride (nitrided SiO), silicon germanium oxide (SiGeO), aluminum oxide (Al 2 O 3 ), or germanium oxide (GeO 2 ), having a thickness T 4 ranging from about 20 Å to about 300 Å. In one embodiment, the screening layer 500 may be another dielectric material, such as silicon nitride or a high-k dielectric material. In various embodiments, the screening layer 500 is formed by deposition, including CVD, such as, for example, APCVD, LPCVD, or PECVD, or by physical deposition methods, such as sputtering. In another embodiment, the screening layer 500 is formed by atomic layer deposition (ALD). The formation of screening layer 500 by deposition, rather than by conventional growth processes, substantially avoids the undesirable consumption of the material of the strained layer 102 by the screening layer 20 during formation thereof.
[0057] After the formation of screening layer 500 , dopants 560 may be introduced into component layers 570 of the wafer 550 to form features such as n-wells or p-wells in, e.g., the strained layer 102 and relaxed layer 104 shown in FIG. 1A , for CMOS devices. The dopants 560 may be n-type or p-type. For example, in an embodiment in which strained layer 102 includes group IV material such as Si, n-type dopants, for example, arsenic (As), phosphorus (P), or antimony (Sb) may be used. Alternatively, p-type dopants may include boron (SB) or indium (In). The dopants 560 may be introduced by ion implantation. During ion implantation, the screening layer 500 provides improved protection against contamination by particles, including metal particles. Further, the screening layer 500 affects the introduction of dopants 560 by scattering them during implantation, thereby reducing the probability of ion channeling. Following the introduction of dopants 560 , the wafer 550 may be annealed. During the annealing step, the screening layer 500 hinders out-diffusion of dopants 560 from the layers 570 .
[0058] Referring to FIG. 2B , in an alternative embodiment, an oxide layer 580 may be grown on the strained layer 102 by, e.g., rapid thermal oxidation, prior to the formation of the screening layer 500 . The oxide layer 580 may include, for example, SiO 2 , nitrided SiO 2 , SiGeO 2 , or GeO 2 , and may have a relatively small thickness T 6 , e.g., ranging from about 5 Å to about 30 Å. Because the oxide layer 580 is relatively thin, its growth does not consume an excessive amount of the strained layer 102 . An oxide layer, when grown on silicon, typically consumes a silicon thickness equal to approximately one-half of the thickness of the oxide grown. For example, if the strained layer 102 is predominantly Si, then the growth of the oxide layer 580 with a thickness T 5 of 20 Å consumes approximately 10 Å of the strained layer 102 . The growth of the oxide layer 580 prior to the formation of screening layer 500 may be desirable in some embodiments. For example, the oxide layer 580 may provide a clean protective coating to strained layer 102 , prior to CVD, a process that may be not as clean as a conventional thermal growth process.
[0059] In some embodiments, the screening layer 500 may be formed at other points during device processing. For example, the screening layer 500 may be formed-prior to a source and drain implantation, or prior to a threshold implantation before gate dielectric formation.
[0060] Referring to FIG. 3A , in yet another embodiment, a pad oxide layer 600 is formed over the strained layer 102 of the semiconductor wafer 650 as part of the STI process whereby the pad oxide layer 600 is used as a stress-mediating underlayer beneath a silicon nitride trench mask layer for STI formation. The wafer 650 can be any one of the wafers 100 , 200 , 300 , or 400 described above with reference to FIGS. 1A-1D . The pad oxide layer 600 may be formed by, for example, CVD, such as APCVD, PECVD, LPCVD, or high-density plasma (P) deposition. The pad oxide layer 600 may include an oxide such as SiO 2 , nitrided SiO 2 , SiGeO 2 , or GeO 2 , and may have a thickness T 7 of, e.g., between about 50 Å and about 500 Å. The formation of the pad oxide layer 600 by conventional thermal growth may consume approximately 25-250 Å of the underlying strained layer 102 . In contrast, by depositing the pad oxide layer 600 , substantially none of the underlying strained layer 102 is consumed.
[0061] In various embodiments, after the formation of the pad oxide layer 600 , a masking layer 660 is formed thereover. The masking layer 660 may include a nitride layer, such as silicon nitride, and may be formed by CVD, such as LPCVD, PECVD, APCVD, or HDP CVD. The masking layer 600 may have a thickness T 7 ranging from about 500 Å to about 2000 Å. The formation of the pad oxide layer 600 prior to the formation of the masking layer 660 inhibits the formation of defects in the strained layer 102 due to stress between the masking layer 660 and the strained layer 102 .
[0062] Subsequent steps may be performed to provide device isolation. The masking layer 660 and the pad oxide layer 600 may be patterned by photolithography and etching. After the masking layer 660 and the pad oxide layer 600 are patterned, exposed portions of the substrate 650 and the underlying-portions of its component layers 670 ate etched to define trenches (not shown). A liner oxide may be formed by oxidation or deposition, and the trenches filled with a deposited dielectric to complete STI formation.
[0063] Referring to FIG. 3B , in still another embodiment, the oxide layer 700 may be grown by, e.g., rapid thermal oxidation on the strained layer 102 prior to the formation of the pad oxide layer 600 . The oxide layer 700 may include, for example, SiO 2 , SiGeO 2 , or GeO 2 , and may have a relatively small thickness T 8 , e.g., ranging between about 5 Å and about 30 Å. Because the oxide layer 700 is relatively thin, its growth does not consume an excessive amount of the strained layer 102 . By thermally growing the oxide layer 700 prior to depositing the pad oxide layer 600 , the strained layer 102 is protected from potentially unclean deposition processing.
[0064] The structures illustrated in the above figures may be further processed to form devices, such as n-type metal-oxide-semiconductor field-effect transistors (nMOSFETs), p-type MOSFETs (pMOSFETs), and CMOS devices.
[0065] The invention may be embodied in other specific forms without departing from the spirit of essential characteristics thereof. The foregoing embodiments are therefore to be considered in all respects illustrative rather than limiting on the invention described herein. | Oxidation methods, which avoid consuming undesirably large amounts of surface material in Si/SiGe heterostructure-based wafers, replace various intermediate CMOS thermal oxidation steps. First, by using oxide deposition methods, arbitrarily thick oxides may be formed with little or no consumption of surface silicon. These oxides, such as screening oxide and pad oxide, are formed by deposition onto, rather than reaction with and consumption of the surface layer. Alternatively, oxide deposition is preceded by a thermal oxidation step of short duration, e.g., rapid thermal oxidation. Here, the short thermal oxidation consumes little surface Si, and the Si/oxide interface is of high quality. The oxide may then be thickened to a desired final thickness by deposition. Furthermore, the thin thermal oxide may act as a barrier layer to prevent contamination associated with subsequent oxide deposition. | 7 |
FIELD OF THE INVENTION
[0001] This invention relates to a transformer which is a combination of capacitances, inductances and also an electrically-isolated mutual inductor (namely, conventional transformer), and called LC combined transformer.
BACKGROUND OF THE INVENTION
[0002] It is well known that the electric transformer, i.e. the conventional voltage/current transformer, widely-used in electrical engineering is actually a mutual inductor with its coupling coefficient k less than but close to 1. In order to address this issue more clearly, for the time being, let's review its electric characteristic equations when neglecting power loss. As the port variables of a mutual inductor supposed as corresponding to those illustrated in FIG. 1( a ), in electrical theory, its electrical characteristic equations in a sinusoidal steady-state circuit are presented as
[0000]
{
V
1
=
jω
L
1
I
1
-
jω
M
I
2
V
2
=
jω
M
I
1
-
jω
L
2
I
2
(
1
)
(
2
)
[0000] where L 1 and L 2 respectively represent self-inductances of the primary winding and the secondary winding of the mutual inductor, M the mutual inductance between them both; ω=2πf. And attention must be paid to its coupling coefficient k and turns ratio n, defined as
[0000]
k
=
M
L
1
L
2
(
3
)
n
=
N
1
N
2
=
L
1
L
2
(
4
)
[0000] Obviously, the mutual inductor in FIG. 1( a ) can be electrically equalized as in FIG. 1( b ), with its equations accordingly equivalently transformed as follows.
[0000]
{
V
a
=
V
1
-
jω
(
1
-
k
)
L
1
I
1
=
jω
kL
1
I
1
-
jω
k
L
1
L
2
I
2
=
L
1
(
jω
k
L
1
I
1
-
jω
k
L
2
I
2
)
V
b
=
V
2
+
jω
(
1
-
k
)
L
2
I
2
=
jω
k
L
1
L
2
I
1
-
jω
kL
2
I
2
=
L
2
(
jω
k
L
1
I
1
-
jω
k
L
2
I
2
)
(
5
)
(
6
)
I
1
=
V
a
jω
kL
1
+
L
2
L
1
I
2
=
V
a
jω
kL
1
+
1
n
I
2
=
I
0
+
1
n
I
2
(
7
)
[0000] In FIG. 1( b ), enclosed in the broken-line box is an ideal transformer that has the simplest voltage and current relations between ports as V a /V b =n, I 1 ′/I 2 =1/n . From Eqs. (5), (6) and (7), for a practical voltage/current transformer or mutual inductor, its voltage ratio is
[0000]
n
=
N
1
N
2
=
V
a
V
b
≠
V
1
V
2
,
[0000] and its current ratio is
[0000]
I
1
=
I
0
+
1
n
I
2
≠
1
n
I
2
,
(
I
0
≠
0
)
;
[0000] which means that it is actually not precise either being used as a voltage transformer for voltage measurement or as a current transformer for current measurement, and that errors exist in it substantially, being determined by the deficiency in its structural principle. The error caused from its leakage inductances (1−k)L 1 and (1−k )L 2 and magnetization inductance kL 1 is called reactive error [Note: Reactive error not only worsens the transforming precision but also increases reactive current of the supply so as to cause more power loss and wastes for transmission line materials]. In addition, there exist the power-dissipation error, or resistive error, from its copper loss and iron loss as well as its non-linearity error from its non-linear cores. Therefore, to meet its required precision, the conventional transformer had to resort to lots of methods for improvements while designed.
[0003] Furthermore, due to complexity of the network loads, there disperse great numbers of higher harmonic waves in the supply network. The higher harmonics not only contribute to energy wastes but also endanger the safety of facilities and loads, causing misoperations and mishaps, seriously interfering with signal transmissions. The conventional transformer is powerless against higher harmonics except for its insulations threatened and cores overheated. Provided that only a few of passive components are added, it comes true that the conventional transformer will become one both transferring power from input to output and also functioning as harmonic isolation from between, i.e. a function of waveform conversion from square-wave to sinusoid being added, which was just a matter of regret, being long expected but not realized yet, in the past.
SUMMERY OF THE INVENTION
[0004] Realizations of the present LC combined transformer of this invention can be divided into three fundamental categories or types according to their functional focuses: current conversion category/type (ideal current transformer), voltage conversion category/type (ideal voltage transformer) and, voltage and current conversion category/type (ideal transformer); besides, though to some extent, they all have the function of waveform conversion from square wave to quasi-sinusoid. Aiming at the imperfections of the widely-used transformer in practical engineering, the invention presents some improvements in principle employing the easiest passive-circuit design approaches to realize the optimum characteristics of current or/and voltage conversions that eliminate the reactive error in principle, optimize structural parameters so as to reduce real-power loss error to minimum, as well as limit non-linear errors of both the inductors and the mutual inductor. To ensure the realizations of their best features, this invention also details the needed specific device selections, linearization processing of inductors, and the integration design approach for the coils and magnetic cores of the inductor and the mutual inductor, not only to achieve in compensation of the errors comprehensively, but also in cost savings with the goal of small devices. The ideal current transformer designed by this invention is suited for sinusoidal current test; the ideal voltage transformer suited for voltage measurement; and being further updated can evolve them into both voltage convertible and current convertible, to realize power transferred with voltage and current in-phased, decreasing the ac line reactive current. The invention also introduces into the designs the new characteristic of waveform conversion from square-wave to quasi-sinusoid, by which the transformers for both waveform conversion (or waveform isolation) and power delivery can be designed, suitable for applications in power electronics, such as in dc transmission, the passive filtering of ac voltage or current, etc. Meanwhile, the usage of push-pull inductor, as well as the technique of the bi-periodically time-shared driving, is brought out, a solution to the problem of the core's unsymmetrical magnetization in double-ended converter under the alternately driving and also an improvement on the issue of cross-conductance of the driving switches.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] The following drawings, which form an important part of this specification, aid to elaborate the presented invention in details:
[0006] FIG. 1 is a principle circuit symbol of a mutual inductor (or conventional transformer) and its equivalent circuit diagram expressed by using an ideal transformer.
[0007] FIG. 2 is the diagram of general circuitry arrangement of the LC combined transformer and those of its equivalent circuits for non-loss analysis and for loss analysis.
[0008] FIGS. 3( a ) and ( b ) are diagrams of the equivalent circuits for non-loss analysis and for loss analysis of current conversion-A type of the LC combined transformer (Ideal Current Transformer A); (c) and (d) diagrams of the configurations employing the design approach of integrated inductor and mutual inductor.
[0009] FIGS. 4( a ) and ( b ) are diagrams of the equivalent circuits for non-loss analysis and for loss analysis of current conversion-B type of the LC combined transformer (Ideal Current Transformer B).
[0010] FIG. 5 are diagrams of the equivalent circuits for non-loss analysis and for loss analysis of the in-phase mode of voltage conversion type of the LC combined transformer.
[0011] FIGS. 6( a ), ( b ) and ( c ) are diagrams of the equivalent circuits for non-loss analysis and for loss analysis of the anti-phase mode of voltage conversion type of the LC combined transformer; (d) is that of its configuration employing the design approach of integrated inductor and mutual inductor; (e) is the simplest arrangement diagram when ωL b −1/ωC b =0; (f) is the arrangement diagram when ωL bx =ωL b −1/ωC b >0; (g) is a diagram for (f) when the integration design approach of inductor and mutual inductor employed.
[0012] FIGS. 7( a ) and ( b ) are duplicates of FIGS. 5( a ) and ( b ); (c) is a diagram of their equivalent circuit expressed by employing an ideal transformer; (d) is for (c), when ωC p2 =1/ωL p1 , namely, Eq.(60) met, evolved into the equivalent circuit diagram of in-phase mode of voltage conversion type of the LC combined transformer.
[0013] FIGS. 8( a ) and ( b ) are duplicates of FIGS. 6( a ) and ( b ); (c) is a diagram of their equivalent circuit expressed by employing an ideal transformer and also of the trends or methods evolving to be an ideal transformer; (d) is in (c) with a compensation capacitor, like C p , C pa or C pb inserted in parallel connection to meet any of Eqs. (66), (67) and (68), the evolved equivalent circuit diagram of anti-phase mode of voltage and voltage conversion type of the LC combined transformer (ideal transformer); (e) and (f), respectively corresponding to FIGS. 6( f ) and ( g ), are diagrams of the ideal transformer configuration.
[0014] FIG. 9( a ) is a duplicate of FIG. 3( a ); (b) is a diagram of its equivalent circuit expressed by employing an ideal transformer; (c) is in (b) with a compensation capacitor, C sa or C sb , inserted in series connection to meet either Eqs. (72) or (73), the evolved equivalent circuit diagram of voltage and current conversion-A type of the LC combined transformer (Ideal Transformer A).
[0015] FIG. 10( a ) is a duplicate of FIG. 4( a ); (b) is a diagram of its equivalent circuit expressed by employing an ideal transformer; (c) is in (b) when n c =k, namely Eq. (78) met, the evolved equivalent circuit diagram of voltage and current conversion-B type of the LC combined transformer (Ideal Transformer B).
[0016] FIG. 11( a ) is the diagram of a principle and trial circuit using either FIG. 5 or FIG. 7 to implement the waveform conversion from square-wave to quasi-sinusoid; (b) is an improved version from (a) by employing the push-pull inductor; (c) are the control and driving signals used for transistor switches in (a) and (b); (d) is the hysteresis loop of the core of inductor L a in (a) in steady-state operation; (e) is the hysteresis loop of the core of inductor L a in (b) in steady-state operation.
[0017] FIGS. IV- 1 ˜IV- 8 are illustrated drawings for Appendix IV “Principle of Mutual Capacitors”.
DETAILED DESCRIPTION OF THE INVENTION
[0018] The general circuitry arrangement of the LC combined transformer is illustrated as in FIG. 2( a ), with the load not included. Circuit components 1 and 3 are inductances L a and L b , with inductance value >0 meaning positive, and the value=0 meaning short-circuited. Circuit components 2 , 4 and 5 are capacitances C m , C b and C p , with capacitance value >0 meaning positive (including C→+∞, short-circuited), and the value=0 meaning open-circuited. 6 is the core magnetic circuit of the mutual inductor, 7 its primary winding N 1 (with inductance L 1 >0), and 8 its secondary winding N 2 (with inductance L 2 >0) and, 6 , 7 and 8 constitute a mutual inductor or conventional transformer. All the circuit components and the mutual inductor herein can be real devices, although their magnitudes or values may be worked out respectively by one or more components based on the principles of series-parallel connections, with their application equivalent for the definition herein, and with the corresponding power loss. Their electrically-interconnections are: One end of inductance 1 and one end of capacitance 2 are together connected to one end of inductor 3 ; the other end of 3 , one end of capacitance 5 , and one end of capacitance 4 connected to each other; and the other end of 4 connected to one end of the winding 7 ; and the other end of 7 connected to the other end of 5 and to the other end of 2 , taken for the common terminal; designating the other end of 1 and the common terminal as the input port of the LC combined transformer, two terminals of the winding 8 as its output port; and with the stipulation that input and output ports herein can be designated at will when needed. Where capacitance 5 should be may be as it is seen herein, or equivalently moved if necessary to parallel with the input or output port. And when capacitance 5 moved away or open-circuited, the position of capacitance 4 may be interchanged with that of inductance 3 , or equivalently moved to series with the input or output port owing to doing so with the circuitry function unchanged except for a different magnitude. The mutual inductor (or transformer) is a double-winding, and it can also be a multi-winding, as long as it can be theoretically converted to a double-winding mutual inductor and utilized within this invention. Any circuit designed out of the configurations of this invention must be working under the circumstance with a constant frequency ω (or f) of periodical sinusoidal wave or of a periodical wave at least unless in peculiar applications.
[0019] The technology scheme of this invention lies in that by utilization of the mutual inductor's leakage inductances (1−k )L 1 and (1−k )L 2 and the magnetization inductance kL 1 , mated with externally connected capacitances or/and inductances, in accordance with the principle of the mutual capacitor [Note: refer to Appendix IV “Principle of Mutual Capacitors”], one or two cascaded mutual capacitors can be constructed with the function of ideal current or voltage conversion; and also cascading with the ideal transformer peeled off the leakage and magnetization inductances, an ideal current transformer, an ideal voltage transformer or an ideal transformer can eventually be achieved.
[0020] FIG. 2( b ) is the diagram of equivalent circuit for non-loss analysis of FIG. 2( a ), and FIG. 2( c ) that for loss analysis. In order to make easier analysis and designs hereafter, let's assume that the LC combined transformer always has a resistive load, R. The arrangement of the specific circuit or variant of every type and mode of the LC combined transformer must be designed in accordance with its featured focuses or its main functions, while the main functions are to be determined by the employed LC unit system or module/block/subunit, named mutual capacitor.
[0021] The LC combined transformer, according to its functional focus, can be divided into three fundamental categories or types: current conversion category/type (ideal current transformer), voltage conversion category/type (ideal voltage transformer), and voltage and current conversion category/type (ideal transformer); The first type has two circuit arrangements of conversion-A type and conversion-B type, the latter two types include in-phase mode and anti-phase mode respectively, and the third type also includes conversion-A type and conversion-B type arrangements.
1. Current Conversion Type LC Combined Transformer (Ideal Current Transformer)
[0022] The Current conversion type of the LC combined transformer, or the ideal current transformer, has its main duties as performing sinusoidal current conversion, current monitoring and measuring or test for instruments, and it also can be designed for ac power delivery, as an ac constant-current generator, or apparatus for current waveform conversion or isolation from square wave to quasi-sinusoid as well.
1-1. Current Conversion-A Type LC Combined Transformer
[0023] Herein details the design of the current conversion-A type LC combined transformer with V 2 side in FIG. 2 as input port and V 1 side as output. Therefore, in FIG. 2 , take inductance 1 and capacitance 4 short-circuited (namely, L a =r a =0, C b →+∞, r b =0), capacitance 5 open-circuited (C p =0, r p →+∞), to obtain the analysis circuit diagram as in FIG. 3 .
[0024] In FIG. 3( a ), the transformer secondary magnetization inductance 10 , leakage inductance 9 , inductance 3 , and capacitance 2 constitute an LC subunit/subsystem (called Δ or π mutual capacitor by the inventor). And the current ratio of this mutual capacitor can be calculated as
[0000]
n
c
=
I
I
2
=
1
k
[
(
1
+
L
b
L
2
)
+
1
-
ω
2
C
m
(
L
2
+
L
b
)
jω
L
2
·
R
]
(
8
)
[0000] If component parameters are set to meet the condition ω 2 C m (L 2 +L b )=1 (9) the ratio will be
[0000]
n
c
=
I
I
2
=
1
k
(
1
+
L
b
L
2
)
(
10
)
[0000] And the current ratio of the entire circuit in FIG. 3( a ) will be
[0000]
I
1
I
2
=
I
1
I
·
I
I
2
=
1
n
·
n
c
=
1
nk
(
1
+
L
b
L
2
)
(
11
)
[0000] This result indicates that the circuit in FIG. 3 , when the condition Eq. (9) met, is an ideal transformer of current conversion, called conversion-A ideal current transformer or ideal current transformer A, independent of both the working frequency ω and the load R. And the ratio is determined only by the selected values of the mutual inductor's turns ratio
[0000]
(
n
=
N
1
N
2
=
L
1
L
2
)
,
[0000] the coupling coefficient
[0000]
(
k
=
M
L
1
L
2
)
,
[0000] the self-inductance L 2 , and the series inductance L b .
[0025] But, all the above conclusions are obtained in the ideal situation. As a matter of fact, the frequency of steady-state sinusoidal current is slightly undulate (for 60 Hz or 50 Hz line frequency has a relative error
[0000]
Δ
f
f
=
Δ
ω
ω
≤
1
%
)
;
[0000] capacitors have their values changeable with the waving ambient temperature; iron-cored inductors are of such a non-linearity that their inductance values are changeable with magnitudes of the current flowing through the coil windings therein (i.e. with the changes of operating points); in addition, wires, cores as well as capacitors in reality are power-dissipated (see FIG. 3( b )); which all would deviate the current ratio from Eq. (11). Here come the errors theoretically derived as follows:
The relative error of the current ratio on frequency change is
[0000]
Δ
n
c
n
c
ω
≈
2
ω
C
m
R
·
Δ
ω
ω
(
12
)
The relative error of the current ratio on capacitance change is
[0000]
Δ
n
c
n
c
C
≈
ω
C
m
R
·
Δ
C
C
(
13
)
The relative error of the current ratio on relative permeability change of the core material is
[0000]
Δ
n
c
n
c
μ
≈
α
ω
C
m
R
α
+
μ
r
·
Δ
μ
r
μ
r
(
14
)
[0000] where, α=l F /l g is the ratio of the core magnetic circuit length to the air-gap length; μ r the relative permeability of the inductors' core material. Moreover, the prerequisite for obtaining this equation is that inductors of L 2 and L b are made of the same core material and of the same α value. The relative error of the current ratio on the devices' power-loss from FIG. 3( b ) is
[0000]
Δ
n
c
n
c
r
≈
(
r
2
+
r
b
+
r
k
+
r
m
)
(
ω
C
m
)
2
R
(
15
)
[0000] The prerequisite for obtaining this equation is that quality factors of the inductors of L 2 and L b are equal and far greater than 1, i.e.
[0000]
ω
L
2
r
2
+
r
k
=
ω
L
b
r
b
>>
1
;
[0000] and also that the loss tangent of capacitor C m should be very small, or ωC m r m =tg δ→0.
[0029] Design Key Points [Note: refer to Appendix I “Design Instructions of the LC Combined Transformer and General Rules for Its Device Selections”]: Attentions should be paid to error equations (12)˜(15) on that (ωC m R) is a key parameter expression for designing errors of the mutual capacitor, called error-designed parameter expression of the mutual capacitor; if it is small the error will be small; meanwhile, Eq. (9) shows that the inductance value of (L 2 +L b ) will be large so as to waste materials and increase sizes. Therefore, proper compromise will be needed in practical designing.
[0030] Device Selections: The criterion of device selections for conversion-A ideal current transformer is to meet the requests of above theoretical designing as far as possible, promoting the inherent features that properties of devices vary along with ambient or/and working conditions in materials, physical structures, as well as manufacture methods etc, namely promoting the linearity, and decreasing devices' power dissipation or reducing influence of devices' power-loss over operation.
[0031] Device selection of capacitor of C m includes that a proper capacitance value should be determined according to the measuring accuracy or error request designed from (12)˜(15), and the right product be chosen according to the requests of, the range of ambient temperature change, working frequency, voltage grade, value precision grade and dielectric loss angle etc. In this case, due to C m in parallel with the low-valued resistive load R (ammeter A) (see FIG. 3( c )), the objective of voltage grade is apt to be met, and the dielectric loss angle tangent, tg δ<10 −3 , of non-polar capacitors of most modern manufacturers is good enough for this application; then by Eq.(13), according to the determined value and the range of ambient temperature change, select the capacitor with appropriate dielectric material.
[0032] The values of parameters L b , L 2 , n and k of the serried inductor and the mutual inductor are to be determined from Eqs. (9)·(11), where the value k must be pre-determined accurately through experiment so as to reduce blindness in the follow-up designing.
[0033] Device selection of the mutual inductor and the serried inductor is a key step for designing in this case, including determination of the coil copper wires, core materials, physical structures and their production methods. The L 1 and L 2 of the mutual inductor must be of an identical core material with low-loss and high saturation magnetic flux density to that of the inductor L b , together with precise calculation of the amount of copper and core to be used, managing to ensure the quality factors of L 2 and L b to be equal and far greater than one, or
[0000]
ω
L
2
r
2
+
r
k
=
ω
L
b
r
b
>>
1.
[0000] Both the series inductor and the mutual inductor must be of a structure of core plus air-gap, which is referred to as linerization processing of inductors/mutual-inductors [Note: refer to Appendix II “Formulas for Linerization Processing of Inductors/Mutual-Inductors”], for air-gapped inductor is calculated as
[0000]
L
2
=
μ
0
N
2
2
S
2
l
g
2
+
l
F
2
/
μ
r
=
μ
0
N
2
2
S
2
l
g
2
[
1
+
(
l
F
2
/
l
g
2
)
/
μ
r
]
=
μ
0
N
2
2
S
2
l
g
2
[
1
+
α
2
/
μ
r
]
=
μ
0
N
2
2
S
2
l
F
2
[
(
l
g
2
/
l
F
2
)
+
1
/
μ
r
]
=
μ
0
N
2
2
S
2
l
F
2
[
1
/
α
2
+
1
/
μ
r
]
L
b
=
μ
0
N
b
2
S
b
l
g
b
+
l
Fb
/
μ
r
=
μ
0
N
b
2
S
2
l
gb
[
1
+
(
l
Fb
/
l
gb
)
/
μ
r
]
=
μ
0
N
b
2
S
2
l
gb
[
1
+
α
b
/
μ
r
]
=
μ
0
N
b
2
S
b
l
Fb
[
(
l
g
b
/
l
Fb
)
+
1
/
μ
r
]
=
μ
0
N
b
2
S
b
l
F
2
[
1
/
α
b
+
1
/
μ
r
]
[0000] where, l F and l g represent the core length and air-gap length respectively, and α i =l Fi /l gi (i=2, b); N i is coil winding turns number; S i is core cross-sectional area. Assuming α=α 2 =l F2 /l g2 =l Fb /l gb =α b , and substitute above two formulas of L 2 and L b into Eq. (11) as
[0000]
I
1
I
2
=
1
nk
(
1
+
L
b
L
2
)
=
1
nk
[
1
+
l
g
2
l
gb
·
S
b
S
2
(
N
b
N
2
)
2
]
=
1
nk
[
1
+
l
F
2
l
Fb
·
S
b
S
2
(
N
b
N
2
)
2
]
(
16
)
[0000] Eq. (16) indicates that the current ratio of this LC combined transformer illustrated in FIG. 3 is absolutely determined by the structural parameters of L 1 and L 2 of the mutual inductor, and of L b of the series inductor, theoretically independent of the value μ r of the core material; which is because the introduction of the air-gap, i.e. the linerization processing of inductors, causes the inductances much more stable, and also because of a principle of cancellation of similarity employed during the design and coil winding of inductors. The relative error of the final current ratio of the entire current transformer influenced by the change of relative permeability of core is obtained from Eq. (14).
1-2. Design Approach of Integrated Inductor and Mutual Inductor
[0034] FIGS. 3( c ) and ( d ) are diagrams of the current conversion-A type LC combined transformer employing the design approach of integrated inductor and mutual inductor.
[0035] The integrated inductor and mutual-inductor includes: the mutual inductor's core magnetic circuit 6 , the series inductor's core magnetic circuit 12 , the mutual inductor's primary winding 7 , the two-in-one common coil winding 8 which serves as both the mutual inductor's secondary winding and also the series inductor's winding, as well as the auxiliary winding 13 . The magnetic circuits of the integrated inductor and mutual inductor may be made from any core material, with any possible shape and any cross-sectional areas, and also may be unequal in length to each other; but the ratios of both, of the core magnetic circuit length to the air-gap length respectively, should be equal or approximately equal. The mutual inductor's turn ratio, coupling coefficient, primary self-inductance, secondary self-inductance, and all the current and power relations are still determined as those of the conventional mutual inductor, but its output total inductance be determined, under the condition of the magnetic circuits with qualified linearity, by the sum of the mutual inductor's secondary self-inductance determined as a conventional mutual inductor plus the inductance determined by windings 8 and 13 , and core 12 all together. In addition, to insure the magnetic circuits of a sound linearity, gaps or clearances l 1 and l 2 may be set as shown in FIG. 3( c ).
[0036] The so-called integration design of the inductor and mutual inductor is actually having the cores of the series inductor and the mutual inductor integrated together, and also having their coil windings integrated together, as a result that they look like only one mutual inductor with a function of the mutual inductor plus the series inductor. Assuming N 2 =N b , that is
[0000]
I
1
I
2
=
1
nk
(
1
+
L
b
L
2
)
=
1
nk
[
1
+
l
g
2
l
gb
·
S
b
S
2
]
=
1
nk
[
1
+
l
F
2
l
Fb
·
S
b
S
2
]
(
16
a
)
[0000] which is the equation of the current ratio of the current conversion-A type LC combined transformer employing the design approach of integrated inductor and mutual inductor. From this equation, only k could be adjusted when n (=N 1 /N 2 ), l F , l g and S are made fixed. However, the variation of k means changing the air-gap length, also meaning the condition of Eq. (9) spoiled. Now, assuming N b =N 2 +ΔN again and substituting it into Eq.(16), we have
[0000]
I
1
I
2
=
1
nk
(
1
+
L
b
L
2
)
=
1
nk
[
1
+
l
g
2
l
gb
·
S
b
S
2
(
1
+
Δ
N
N
2
)
]
=
1
nk
[
1
+
l
F
2
l
Fb
·
S
b
S
2
(
1
+
Δ
N
N
2
)
]
(
16
b
)
[0000] As seen in this equation, the variation of ΔN, i.e. changing turn number of the auxiliary winding, changes only the inductance of L b , by which comes true the needed micro-adjustment, with the layout of the coil windings as in FIG. 3( d ).
[0037] Like the design of every other product, the design of this product has to be improved through repeated experiments so finally to be as expected. Moreover, a suggestion is made, if possible, that the same kind of magnetic powder core material should be employed for the two pairs of cores of F 1 and F 2 illustrated as in FIG. 3( c ) or ( d ); whose advantage is easy to have an equal α value for both.
[0038] It saves materials to design an LC combined transformer by employing the integration design of inductor and mutual inductor (a coil winding of L b saved) so that the total size decreases because the air-gapped cores set the current transformer free from heavy burden of the balance of the magnetic potentials or ampere-turns, and meanwhile the requirements of the window areas of the cores and of the insulation grades decrease accordingly. However, these advantages can be brought into play only at high-current detections because a fixed LC value must be set, by Eq. (9), for the current conversion-A type LC combined transformer. It is also easy to notice from Eqs.(10) and (11) that the current conversion-A type LC combined transformer, as a matter of fact, performs two current conversions that 1/n is the first current conversion, namely the current ratio of the conventional current transformer, and the second is that of the mutual capacitor which is determined by Eq. (10), so that a very high rating of current conversion ratio could be achieved.
[0039] In the integrated inductor and mutual inductor ( FIG. 3( c ) or ( d )), the function of a mutual inductor occurs between coil windings N 1 and N 2 while N 2 on its own functions as two inductances in series as
[0000]
L
Total
=
L
F
1
+
L
F
2
=
μ
0
N
2
2
S
F
1
l
g
1
l
F
1
/
μ
r
+
μ
0
N
b
2
S
F
2
l
g
2
l
F
2
/
μ
r
(
17
)
[0000] where, meanings of the symbols are the same as previous, and the subscripts in accordance with the core number F 1 and F 2 [Note: this equation is obtained under the condition of a good linearity]. And proof of this equation omitted.
1-3. Current Conversion-B Type LC Combined Transformer
[0040] The circuitry design of the current conversion-B type LC combined transformer is also presented as the formation with V 2 side in FIG. 2 as input port and V 1 side as output. In FIG. 2 , make inductances 1 and 3 short-circuited (namely, L a =r a =0, L b =r b1 =0), capacitance 5 open-circuited (C p =0, r p →+∞), to obtain the analysis circuit diagram as in FIG. 4 .
[0041] In FIG. 4( a ), the mutual inductor's secondary magnetization inductance 10 , leakage inductance 9 , capacitances 2 and 4 constitute an LC subunit/subsystem (called Δ or π mutual capacitor). And the current ratio of this mutual capacitor can be calculated as
[0000]
n
c
=
I
1
I
2
=
1
k
{
(
1
-
1
ω
2
L
2
C
b
)
+
j
[
ω
C
m
-
1
ω
L
2
(
1
+
C
m
C
b
)
R
]
}
(
18
)
[0000] If component parameters are set to meet the condition
[0000]
ω
2
L
2
(
C
b
⊥
C
m
)
=
ω
2
L
2
(
C
b
C
m
C
b
+
C
m
)
=
1
(
19
)
then
n
c
=
I
1
I
2
=
1
k
(
1
-
1
ω
2
L
2
C
b
)
=
1
ω
2
kL
2
C
m
=
C
b
k
(
C
b
+
C
m
)
(
20
)
[0000] And notice that n c <1 in most cases. Thus the current ratio of the entire circuit in FIG. 4( a ) will be
[0000]
I
1
I
2
=
I
1
I
·
I
I
2
=
1
n
·
n
c
=
C
b
nk
(
C
b
+
C
m
)
(
21
)
[0000] And this result denotes that the circuit in FIG. 4 , when the condition Eq. (19) is met, is also an ideal transformer of current conversion, called the conversion-B ideal current transformer or ideal current transformer B, independent of both the working frequency ω and the load R. And the ratio is determined only by the selected values of the mutual inductor's turns ratio (n=N 1 /N 2 =√{square root over (L 1 /L 2 )}), the coupling coefficient
[0000]
(
k
=
M
L
1
L
2
)
,
[0000] the series capacitance C b , and the parallel capacitance C m .
[0042] Here give the errors theoretically derived as follows: The relative error of the current ratio on frequency change is
[0000]
Δ
n
c
n
c
ω
≈
1
+
[
ω
(
C
b
+
C
m
)
R
]
2
·
2
C
m
C
b
·
Δ
ω
ω
(
22
)
[0000] The relative error of the current ratio on capacitance change is
[0000]
Δ
n
c
n
c
C
≈
1
+
[
ω
(
C
b
+
C
m
)
R
]
2
·
C
m
C
b
·
Δ
C
C
(
23
)
[0000] The relative error of the current ratio on relative permeability change of the core material is
[0000]
Δ
n
c
n
c
μ
≈
1
+
[
ω
(
C
b
+
C
m
)
R
]
2
·
C
m
C
b
·
α
α
+
μ
r
Δ
μ
r
μ
r
(
24
)
[0000] where, α=l F /l g is the ratio of the core magnetic circuit length to the air-gap magnetic circuit length; μ r the relative permeability of the inductors' core material. Moreover, the prerequisite for obtaining this equation is that inductors of (1−k)L 2 and kL 2 are of the same α value. The relative error of the current ratio on the devices' power-loss obtained from FIG. 4( b ) is
[0000]
Δ
n
c
n
c
r
≈
(
r
2
+
r
b
+
r
k
+
r
m
)
(
ω
C
m
)
2
R
(
25
)
[0000] The prerequisite for obtaining this equation is that quality factor of the inductor L 2 is far greater than 1, i.e.
[0000]
ω
L
2
r
2
+
r
k
>>
1
;
[0000] and also that the loss tangent of capacitors C b and C m should be very small, that is ωC b r b =C m r m =tgδ→0.
[0043] Design Key Points [Note: see Appendix I “Design Instructions of the LC Combined Transformer and General Rules for Its Device Selections”]: Attentions should be paid to error equations (22)˜(25) on that
[0000]
(
1
+
[
ω
(
C
b
+
C
m
)
R
]
2
·
C
m
C
b
)
[0000] is the error-designed parameter expression of the mutual capacitor; when the values of
[0000]
(
C
b
+
C
m
)
and
C
m
C
b
[0000] set small the error will be very small; meanwhile, Eq. (19) shows that the inductance of L 2 will be large so as to waste materials and increase the sizes. Therefore, proper compromise will be needed in practical designing.
[0044] Device Selections: Device selections of capacitances C b and C m include proper determination of their values on designed measuring accuracy or error requirements, choosing the right products according to the requests of, the range of ambient temperature change, working frequency, voltage grade, value precision grade and dielectric loss angle etc, and characteristics of both capacitances changing with the environment expected as keeping in accordance. The request for the mutual capacitor is of a precise k value, L 2 with a good linearity, and low power loss.
2. Voltage Conversion Type LC Combined Transformer (Ideal Voltage Transformer)
[0045] The voltage conversion type of the LC combined transformer, or the ideal voltage transformer, has its main usages of performing sinusoidal voltage conversion, voltage monitoring and measuring/test for instruments; and it also can be designed for ac power delivery, or as an apparatus for voltage waveform conversion or isolation from square-wave to quasi-sinusoid as well. The voltage conversion type of the LC combined transformer includes two realizations of circuit arrangements of in-phase mode and anti-phase mode.
2-1. In-Phase Mode of the Voltage Conversion Type LC Combined Transformer
[0046] In the circuit diagram of FIG. 2 , let inductance 3 short-circuited (i.e. L b =r b1 =0), capacitance 5 open-circuited (i.e. C p =0, r p →+∞) to obtain the in-phase mode of the voltage conversion type LC combined transformer illustrated in FIG. 5( a ). In order to analyze it, let's split capacitance 4 into capacitances 4 a and 4 b (namely, C b splited into C b1 and C b2 and
[0000]
C
b
=
C
b
1
⊥
C
b
1
=
C
b
1
C
b
2
C
b
1
+
C
b
2
)
,
[0000] and equivalently reflect the leakage inductance 11 on the right side of the mutual inductor onto the left side as inductance 14 , shown as in FIG. 5( b ); where inductance 1 , capacitances 2 and 4 a constitute the first LC subunit/subsystem (T or Y mutual capacitor); capacitance 4 b, two leakage inductances 9 and 14 of the mutual inductor, and its magnetization inductance 10 constitute the second; and the third part is the ideal transformer enclosed in the broken-line box.
[0047] For the first T mutual capacitor, assuming that it has an equivalent load of resistance R 1 , its voltage ratio will be
[0000]
n
v
1
=
V
1
V
x
=
(
1
-
ω
2
L
a
C
m
)
+
1
j
ω
C
b
1
[
1
-
ω
2
L
a
(
C
b
1
+
C
m
)
]
1
R
1
(
26
)
[0000] If setting the component parameters to meet the condition ω 2 L a (C b1 +C m )=1 (27) we have
[0000]
n
v
1
=
1
-
ω
2
L
a
C
m
=
C
b
1
C
b
1
+
C
m
(
28
)
[0000] Then, the relative error of the voltage ratio on frequency change is
[0000]
Δ
n
v
1
n
v
1
ω
≈
1
+
(
1
ω
n
v
1
C
m
R
1
)
2
·
2
(
1
n
v
1
-
1
)
Δω
ω
(
29
)
[0000] The relative error of the voltage ratio on capacitance change is
[0000]
Δ
n
v
1
n
v
1
C
≈
1
+
(
1
ω
n
v
1
C
m
R
1
)
2
·
(
1
n
v
1
-
1
)
Δ
C
m
C
m
;
(
when
Δ
C
b
1
C
b
1
=
Δ
C
m
C
m
)
(
30
)
[0000] The relative error of the voltage ratio on relative permeability change of the core material is
[0000]
Δ
n
v
1
n
v
1
µ
≈
1
+
(
1
ω
n
v
1
C
m
R
1
)
2
·
α
(
α
+
μ
r
)
(
1
n
v
1
-
1
)
Δμ
r
μ
r
(
31
)
[0000] where, α=l F /l g is the ratio of the core magnetic circuit length to the air-gap magnetic circuit length; μ r the relative permeability of the inductors' core material.
[0048] The relative error of the current ratio on the devices' power-loss obtained from FIG. 5( c ) is
[0000]
Δ
n
v
1
n
v
1
r
≈
r
a
n
v
1
2
R
1
(
32
)
[0000] The prerequisite for meeting Eq. (32) is that the loss angle tangents of capacitances C b1 and C m are equal or approximately equal, that is tg δ b1 =ωC b1 r b1 ≈ωC m r m =tg δ m , as well as tg δ→0.
[0049] Also, it is noted that, when output power of this mutual capacitor is P,
[0000]
R
1
=
V
x
2
P
=
V
1
2
n
v
1
2
P
(
33
)
[0050] Design Key Points [Note: see Appendix I “Design Instructions of the LC Combined Transformer and General Rules for Its Device Selections”]: From the error equations,
[0000]
1
+
(
1
ω
n
v
1
C
m
R
1
)
2
·
(
1
n
v
1
-
1
)
[0000] will be found out as the error-designed parameter expression of this mutual capacitor; if the value of (ωC m R 1 ) set large the error will be small, but its capacity of load carrying will be limited; to improve which there exist some ways, increasing the value of C m or/and ω.
[0051] Device Selections: Device selections of capacitances require the value precision grade and their temperature coefficient taken as high as possible based on the requirements of design. The temperature coefficients of C b1 and C m are needed to be in accordance, and the loss angle tangents should be equal or approximately equal, that is tg δ b1 =ωC b1 r b1 ≈ωC m r m =tg δ m , as well as tg δ→0. Meanwhile, the maximum voltages on the capacitances C b1 and C m are calculated as the following equations (assuming the mutual capacitor's maximum load as R 1m ).
[0000]
U
b
1
max
≥
2
V
x
ω
C
b
1
R
1
m
=
2
V
ω
C
b
1
n
v
1
R
1
m
=
2
V
1
(
1
-
n
v
1
)
ω
C
m
n
v
1
2
R
1
m
(
34
)
U
m
max
≥
2
V
x
1
+
(
1
ω
C
b
1
R
1
m
)
2
=
2
V
1
n
v
1
1
+
(
1
ω
C
b
1
R
1
m
)
2
=
2
V
1
n
v
1
1
+
(
1
-
n
v
1
ω
C
m
n
v
1
R
1
m
)
2
(
35
)
[0000] The core of inductance L a should be selected of a low-loss core material, with its magnetic circuit length ratio α of the iron core to the air gap chosen by Eq. (31) to meet the design requirements and also according to the material specifications.
[0052] Assume R 2 as the equivalent load of resistance for the second mutual capacitor; its voltage ratio is
[0000]
n
v
2
=
V
x
V
y
=
1
k
[
(
1
-
1
ω
2
L
1
C
b
2
)
+
1
-
ω
2
(
1
-
k
2
)
L
1
C
b
2
jω
C
b
2
·
R
2
]
(
36
)
[0000] If setting the component parameters to meet the condition ω 2 (1−k 2 )L 1 C b2 =1 (37) we have
[0000]
n
v
2
=
V
x
V
y
=
1
k
(
1
-
1
ω
2
L
1
C
b
2
)
=
k
(
38
)
[0000] The relative error of the voltage ratio on frequency change is
[0000]
Δ
n
v
2
n
v
2
ω
≈
1
+
(
ω
L
1
R
2
)
2
·
2
(
1
k
2
-
1
)
Δω
ω
(
39
)
[0000] The relative error of the voltage ratio on capacitance change is
[0000]
Δ
n
v
2
n
v
2
C
≈
1
+
(
ω
L
1
R
2
)
2
·
(
1
k
2
-
1
)
Δ
C
b
2
C
b
2
(
40
)
[0000] The relative error of the voltage ratio on relative permeability change of the core material is
[0000]
Δ
n
v
2
n
v
2
μ
≈
1
+
(
ω
L
1
R
2
)
2
·
(
1
k
2
-
1
)
α
(
α
+
μ
r
)
Δμ
r
μ
r
(
41
)
[0000] where, α=l F /l g is the ratio of the core magnetic circuit length to the air-gap magnetic circuit length; μ r the relative permeability of the inductors' core material.
[0053] The relative error of the current ratio on the devices' power-loss obtained from FIG. 5( c ) is
[0000]
Δ
n
v
2
n
v
2
r
≈
r
b
2
+
r
1
(
k
+
1
)
k
2
R
2
(
42
)
[0000] The prerequisite for Eq. (42) is that the quality factors of inductances (1−k)L 1 and kL 1 are equal. Design Key Points [Note: refer to Appendix I “Design Instructions of the LC Combined Transformer and General Rules for Its Device Selections”]: The error-designed parameter expression of this mutual capacitor is
[0000]
1
+
(
ω
L
1
R
2
)
2
·
(
1
k
2
-
1
)
;
[0000] which denotes that, to minimize the error, the value of
[0000]
(
ω
L
1
R
2
)
[0000] should be as small as possible, and the k value as large as possible.
[0054] Device Selections: Device selection for capacitance C b2 is the same as that for C b1 , because they will be merged together as one in the end, and the maximum voltage on C b2 is calculated as follows
[0000]
U
b
2
max
=
ω
(
1
-
k
2
)
L
1
·
n
v
1
P
V
1
=
ω
(
1
k
-
k
)
L
1
·
P
nV
2
(
43
)
[0000] The core material for L 1 or the mutual inductor should be selected, from Eqs. (41) and (42), of a high permeability and low core loss material. The prerequisite for Eq. (42) is that the quality factors of inductances (1−k)L 1 and kL 1 are equal, or [ω(1−k)L 1]/r 1 =kL 1 /r k , which is not easy to get into practice because r 1 is mainly the copper loss while r k is mainly iron loss. Try to decrease the difference between both as far as possible so as to be more accurate to estimate error by Eq. (42).
[0055] Now from Eqs. (28) and (38) as well as the ideal transformer's ratio n, the voltage ratio of entire in-phase mode of the voltage conversion type LC combined transformer will have the equation as
[0000]
n
v
=
V
1
V
2
=
V
1
V
x
·
V
x
V
y
·
V
y
V
2
=
n
v
1
·
n
v
2
·
n
=
knn
v
1
=
knC
b
1
C
b
1
+
C
m
(
44
)
[0000] Eq. (44) indicates that the circuit illustrated in FIG. 5 , under the conditions of above discussed, is an ideal voltage transformer independent of the working frequency ω and the load R. It also shows that polarities of voltage conversion of V 1 and V 2 are in-phased, therefore, called the in-phase mode of the voltage conversion type LC combined transformer or in-phased ideal voltage transformer.
2-2. Anti-Phase Mode of the Voltage Conversion Type LC Combined Transformer
[0056] In FIG. 2 , let capacitance 5 open-circuited (i.e. C p =0, r p →+∞), though not excluding a round-off design of having capacitance 4 shot-circuited (i.e. C b →+∞, r b2 =0), to obtain the anti-phase mode of the voltage conversion type LC combined transformer illustrated in FIG. 6( a ). Imitating what's done for the in-phase mode, equivalently reflect the leakage inductance 11 on the right side of the mutual inductor onto the left side as inductance 14 , shown as in FIG. 6( b ); where inductances 1 and 3 , plus capacitance 2 constitute the first LC subunit/subsystem (T or Y mutual capacitor); capacitance 4 , the leakage inductances 9 and 14 of the mutual inductor, and its magnetization inductance 10 constitute the second LC subunit/subsystem (T or Y mutual capacitor); and the third part is the ideal transformer enclosed in the broken-line box.
[0057] Still, assume that the first T mutual capacitor has an equivalent load of resistance R 1 , then the voltage ratio will be
[0000]
n
v
1
=
V
1
V
x
=
(
1
-
ω
2
L
a
C
m
)
+
jω
(
L
a
+
L
b
-
ω
2
L
a
L
b
C
m
)
1
R
1
(
45
)
[0000] If setting component parameters to meet condition
[0000]
ω
2
C
m
=
(
L
a
L
b
L
a
+
L
b
)
=
ω
2
C
m
(
L
a
//
L
b
)
=
1
(
46
)
[0000] we have
[0000]
n
v
1
=
1
-
ω
2
L
a
C
m
=
-
L
a
L
b
(
47
)
[0000] Thus, the relative error of the voltage ratio on frequency change is
[0000]
Δ
n
v
1
n
v
1
ω
≈
1
+
(
n
v
1
-
1
ω
n
v
1
C
m
R
1
)
2
·
2
(
1
-
1
n
v
1
)
Δω
ω
(
48
)
[0000] The relative error of the voltage ratio on capacitance change is
[0000]
Δ
n
v
1
n
v
1
C
≈
1
+
(
n
v
1
-
1
ω
n
v
1
C
m
R
1
)
2
·
(
1
-
1
n
v
1
)
Δ
C
m
C
m
(
49
)
[0000] The relative error of the voltage ratio on relative permeability change of the core material is
[0000]
Δ
n
v
1
n
v
1
μ
≈
1
+
(
n
v
1
-
1
ω
n
v
1
C
m
R
1
)
2
·
α
(
α
+
μ
r
)
(
1
-
1
n
v
1
)
Δμ
r
μ
r
(
50
)
[0000] where, α=l F /l g is the ratio of the core magnetic circuit length to the air-gap magnetic circuit length; μ r the relative permeability of the inductors' core material. And the prerequisite for obtaining Eq. (50) is that L a and L b have cores of the same material and also of the same α value. The relative error of the current ratio on the devices' power-loss obtained from FIG. 6( c ) is
[0000]
Δ
n
v
1
n
v
1
r
≈
2
(
1
-
n
v
1
)
r
b
R
1
(
51
)
[0000] The prerequisite for Eq. (51) is that the quality factors or Q-values of inductances L a and L b should be equal, that is ωL a /r a =ωL b /r b =Q, as well as r m =r a //r b be managed to achieve. Besides, the value of R 1 still could be worked out by Eq. (33).
[0058] Design Key Points [Note: refer to Appendix I “Design Instructions of the LC Combined Transformer and General Rules for Its Device Selections”]: This mutual capacitor has an error-designed parameter expression as
[0000]
1
+
(
n
v
1
-
1
ω
n
v
1
C
m
R
1
)
2
·
1
-
1
n
v
1
,
[0000] which shows that, to have a small error, the values of C m and n v1 have to be large. In addition, if the positions of L b and C b switch to each other in the circuit, circuit function stays unchanged so that L b and the mutual inductor could be constructed as an integrated inductor and mutual inductor as schematically illustrated in FIG. 6( d ). Device Selections: Device selection of capacitance C m requires the value precision grade and the temperature coefficient taken as high as possible based on the requests of design. The maximum voltage on C m will be determined as
[0000]
U
m
max
≥
2
V
x
1
-
(
ω
L
b
R
1
)
2
=
2
V
1
n
v
1
1
+
(
ω
L
b
R
1
)
2
(
52
)
[0000] Moreover, Eq. (51) requires that C m 's equivalent series resistance, r m =r a //r b , to which a solution is to insert a proper resistance connected in series with it, with the only concerning that you should weigh and balance the necessity of paying a price of power dissipation. Inductors of L a and L b are selected as stated before, with the requests of the same a value and of the same Q-value.
[0059] The second subunit is the same as that in the in-phase mode [Note: but now in FIG. 6 , C b must take the place of C b2 in FIG. 5 ]. Thus, borrow the result from that as is in the in-phase mode and obtain the voltage ratio of the anti-phase mode of the voltage conversion type LC combined transformer as
[0000]
n
v
=
V
1
V
2
=
V
1
V
x
·
V
x
V
y
·
V
y
V
2
=
n
v
1
·
n
v
2
·
n
=
knn
v
1
=
-
kn
L
a
L
b
(
53
)
[0000] This equation indicates that the circuit illustrated in FIG. 6 , when satisfying the conditions of above assumed, is also an ideal voltage transformer, with the polarities of voltages of input and output anti-phased, which is why, called the anti-phase mode of the voltage conversion type LC combined transformer or anti-phased ideal voltage transformer.
[0060] If one more step further, make
[0000]
ω
L
b
-
1
ω
C
b
=
0
[0000] in FIGS. 6( a ) and ( b ); from Eqs. (37), (46) and (47), to get the following L b =(1−k 2)L 1 (54) and
[0000] ω 2 C m (1−k 2 )L 1 =1+1/|n v1 | (55)
[0000] Hence the circuit has its simplified arrangement (see FIG. 6( e )). Similarly, once more assume
[0000]
ω
L
bx
=
ω
L
b
-
1
ω
C
b
>
0
,
i
.
e
.
when
L
bx
=
L
b
-
1
ω
2
C
b
=
L
b
-
(
1
-
k
2
)
L
1
>
0
(
56
)
[0000] the circuit could leave out C b as in FIG. 6( f ) as well as in FIG. 6( g ) by the integration design of inductor and mutual inductor.
3. Voltage and Current Conversion Type LC Combined Transformer (Ideal Transformer)
[0061] The voltage and current conversion type of the LC combined transformer, or the ideal transformer, is actually the technological extension expanded either from the voltage conversion type LC combined transformer to the current conversion type, or from the current conversion type LC combined transformer to the voltage conversion type. Accordingly, for the former there exist two configurations of circuitry designs of in-phase mode and anti-phase mode; while for the latter there also exist two circuitry realizations of conversion-A type and conversion-B type.
3-1. In-Phase Mode of the Voltage and Current Conversion Type LC Combined Transformer
[0062] Firstly review the in-phase mode of the voltage conversion type LC combined transformer and redraw the circuit diagrams in FIGS. 5( a ) and ( b ) as in FIGS. 7( a ) and ( b ). In FIG. 7( b ), of the first T mutual capacitor consisting of inductance 1 , capacitances 2 and 4 a, currents
[0000]
I
1
=
V
1
-
v
m
j
ω
L
a
=
V
1
-
V
x
j
ω
L
a
-
(
v
m
-
V
x
)
j
ω
C
b
1
j
ω
L
a
·
j
ω
C
b
1
=
(
1
-
1
n
v
)
V
1
j
ω
L
a
+
I
x
ω
2
L
a
C
b
1
=
j
ω
(
C
m
n
v
1
)
V
1
+
1
n
v
1
I
x
j
ω
C
p
1
V
1
+
1
n
v
1
I
x
,
(
C
p
1
=
C
m
n
v
1
)
(
57
)
I
x
=
n
v
1
I
1
-
j
ω
C
m
V
1
=
n
v
1
I
1
-
j
ω
(
n
v
1
C
m
)
V
2
=
n
v
1
I
1
-
j
ω
C
p
2
V
2
,
(
C
p
2
=
n
v
1
C
m
)
(
58
)
[0000] From Eqs. (28) and (58), an equivalent circuit, between V 1 and V x in FIG. 7( c ), of the ideal transformer 15 and its secondary-side paralleled capacitance 16 or C p2 is evolved. In the same way, of the second T mutual capacitor consisting of capacitance 4 b, the mutual inductor's two leakage inductances 9 and 14 , and also the magnetization inductance 10 , there is an current as
[0000]
I
x
=
V
x
-
v
k
j
ω
(
1
-
k
)
L
1
+
1
j
ω
C
b
2
=
V
x
-
V
y
j
ω
(
1
-
k
)
L
1
+
1
j
ω
C
b
2
-
(
v
k
-
V
y
)
j
ω
(
1
-
k
)
L
1
[
1
-
1
ω
2
C
b
2
(
1
-
k
)
L
1
]
=
(
1
-
1
n
v
2
)
V
x
j
ω
(
1
-
k
)
L
1
[
1
-
1
ω
2
C
b
2
(
1
-
k
)
L
1
]
+
1
n
v
2
I
y
=
V
x
j
ω
(
n
v
2
·
kL
1
)
+
1
n
v
2
I
y
=
V
x
j
ω
L
p
1
+
1
n
v
2
I
y
,
(
L
p
1
=
n
v
2
·
kL
1
=
k
2
L
1
)
(
59
)
[0000] From Eqs. (38) and (59), achieve the equivalent circuit of inductance 17 in parallel with the primary of the ideal transformer 18 , evolved from that between V x and V y in FIG. 7( b ). Then, assume that the component parameters satisfying the condition ωC p2 =1/ωL p1 , i.e.
[0000]
ω
2
C
p
2
L
p
1
=
ω
2
n
v
1
C
m
k
2
L
1
=
ω
2
(
1
-
n
v
1
)
C
b
1
k
2
L
1
=
ω
2
C
b
1
C
m
C
b
1
+
C
m
k
2
L
1
=
ω
2
k
2
L
1
(
C
b
1
⊥
C
m
)
=
1
(
60
)
[0000] and notice Eq. (27) and C b =C b1 ⊥C b2 , we achieve that, when
[0000]
ω
2
L
1
(
C
b
C
m
C
b
+
C
m
)
=
ω
2
L
1
(
C
b
⊥
C
m
)
=
1
,
(
C
b
=
C
b
1
C
m
(
C
b
1
+
C
m
)
/
k
2
-
C
b
1
)
(
61
)
[0000] FIG. 7( c ) is in circuitry equalized as FIG. 7( d ) with its voltage and current equations as
[0000]
{
V
1
V
2
=
V
1
V
x
·
V
x
V
y
·
V
y
V
2
=
n
v
1
·
n
v
2
·
n
=
n
v
=
nkC
b
1
C
b
1
+
C
m
=
n
k
·
C
b
C
b
+
C
m
(
62
)
I
1
I
2
=
I
1
I
x
·
·
I
x
·
I
y
·
I
y
I
2
=
1
n
v
1
·
1
n
v
2
·
1
n
=
1
n
v
=
C
b
1
+
C
m
nkC
b
1
=
k
n
(
1
+
C
m
C
b
)
(
63
)
[0000] They appear completely as the forms of ideal transformer's equations, termed the in-phase mode of the voltage and current conversion type LC combine transformer or in-phased ideal transformer.
[0063] And from Eqs. (27) and (61) we have
[0000]
L
a
=
1
ω
2
(
C
b
1
+
C
m
)
=
1
-
n
v
1
ω
2
C
m
=
1
ω
2
C
m
[
1
-
C
b
k
2
(
C
b
+
C
m
)
]
(
64
)
[0064] Design Key Points: The in-phase mode of the voltage and current conversion type LC combine transformer (see FIG. ( 7 )) is just the improvement or upgraded from the in-phase mode of the voltage conversion type LC combine transformer. Hence, its error analysis, design key points, and device selections all are the same as the according contents respectively of the latter stated above, with a difference that the former has functioned as the input and output current in-phased just one-step further beyond the latter.
[0065] However, the two mutual capacitors of the in-phased ideal transformer in FIG. 7 are implicated with each other during the specific designing, especially on the adjustment. In practical engineering, especially on spot test or adjustment, deviations of parameter values, influenced by lots of factors, are fated, although parameter value precision grades are ensured as high as possible in the course of designing and manufacturing; and micro-adjustments are ineluctable. Here present two methods shown in the following that can be used for on-site micro-adjustments.
[0066] Method 1: Take L p as a micro-adjusted inductance with its value far below L 1 , and connect L p in series with the primary winding N 1 of the mutual inductor. Then Eq. (36) will become
[0000]
n
v
2
=
V
x
V
y
=
1
k
[
(
1
-
1
ω
2
L
1
C
b
2
)
+
1
-
ω
2
C
b
2
[
(
1
-
k
2
)
L
1
+
L
p
]
j
ω
C
b
2
·
R
2
]
(
36
a
)
[0000] Accordingly, Eq. (37) could be as ω 2 C b2 [(1−k 2 )L 1 +L p ]=1 (37a) Eq. (38) as
[0000]
n
v
2
=
V
x
V
y
=
1
k
(
1
-
1
ω
2
L
1
C
b
2
)
=
k
(
1
-
L
p
k
2
L
1
)
,
or
(
38
a
)
[0067] Method II: Put a micro-adjusted inductance L s (<<L 2 ) in series with the secondary side of the mutual inductor. Then Eq. (36) will be turned as
[0000]
n
v
2
=
V
x
V
y
=
1
k
[
(
1
-
1
ω
2
L
1
C
b
2
)
+
(
1
+
L
s
/
L
1
)
-
ω
2
C
b
2
L
1
(
1
+
L
s
/
L
2
-
k
2
)
j
ω
C
b
2
·
R
2
]
(
36
b
)
ω
2
L
1
C
b
2
(
1
-
k
2
1
+
L
s
/
L
2
)
=
ω
2
L
1
C
b
2
(
1
-
kn
v
2
)
=
1
(
37
b
)
n
v
2
=
V
x
V
y
=
1
k
(
1
-
1
ω
2
L
1
C
b
2
)
=
k
1
+
L
s
/
L
2
(
38
b
)
[0068] Moreover, the two methods stated above are suited only when the k value of the mutual inductor is slightly greater than originally tested or L 1 a bit less than designed. To match their usages, the coil winding of L 1 should be pre-set a tap at the position of just a little bit fewer turns next to an end to make it have an inductance slightly less than originally designed. In this way, once either of the two cases above-mentioned occurs, the pre-set tap in series with the L p , take Method I for an example, could be connected to where N 1 ought to so that flexible micro-adjustments could be realized. Obviously, such a way has also slightly changed the ratio of the entire transformer; when necessary, revision should be made.
3-2. Current Conversion-A Type LC Combined Transformer
[0069] In the same way, redraw the circuit diagrams of the anti-phase mode of the voltage conversion type LC combined transformer in FIGS. 6( a ) and ( b ) as in FIGS. 8( a ) and ( b ). In FIG. 8( b ), of the first T mutual capacitor consisting of inductances 1 and 3 , capacitance 2 , currents
[0000]
I
x
=
n
v
1
I
1
-
V
x
j
ω
⌊
(
L
a
//
L
b
)
/
n
v
1
⌋
=
n
v
1
I
1
-
V
2
j
ω
L
p
2
,
(
L
p
2
=
L
a
//
L
b
n
v
1
)
(
65
)
[0000] By Eqs. (47) and (65), electrically equalize the first mutual capacitor in FIG. 8( b ) as an arrangement of ideal transformer 19 and its secondary in parallel with inductance 20 illustrated in FIG. 8( c ). Of the second T mutual capacitor in FIG. 8( b ) consisting of capacitance 4 , both of the mutual inductor's leakage inductances 9 and 14 , and the magnetization inductance 10 , the expressions of I x and L p1 are identical to Eq. (59) so that its equivalent circuit could be the same as in FIG. 7( c ) of inductance 17 or L p1 in parallel with the primary of ideal transformer 18 , and the circuit in FIG. 8( b ) will be in circuitry equalized as in FIG. 8( c ). Furthermore, if a reactive compensation capacitance 5 or C p inserted in parallel connection at the position of V x in FIG. 8( c ), or according to practical necessity, either capacitance 5 a or C pa at V 1 , or capacitance 5 b or C pb at V 2 , with their values as
[0000]
C
p
=
1
ω
2
(
L
p
1
//
L
p
2
)
=
1
ω
2
(
1
k
2
L
1
+
1
+
L
a
/
L
b
L
b
)
(
66
)
C
pa
=
C
p
/
n
v
1
2
=
1
ω
2
(
1
k
2
L
1
+
1
+
L
a
/
L
b
L
b
)
(
L
b
L
a
)
2
(
67
)
C
pb
=
k
2
n
2
C
p
=
n
2
ω
2
[
1
L
1
+
k
2
(
1
+
L
a
/
L
b
)
L
b
]
(
68
)
[0000] After compensated, functions of the circuit in FIG. 8 can be specifically and equivalently described as the form of ideal transformers illustrated in FIG. 8( d ), with its voltage and current relations as
[0000]
{
V
1
V
2
=
V
1
V
x
·
V
x
V
y
·
V
y
V
2
=
n
v
1
·
n
v
2
·
n
=
n
v
=
-
nkL
a
L
b
(
69
)
I
1
I
2
=
I
1
I
x
·
·
I
x
·
I
y
·
I
y
I
2
=
1
n
v
1
·
1
n
v
2
·
1
n
=
1
n
v
=
-
L
b
nkL
a
(
70
)
[0000] These equations show the relations of anti-phased voltages and currents, termed the anti-phase mode of the voltage and current conversion type LC combined transformer or anti-phased ideal transformer. As well, here present the circuit arrangements of the ideal transformers upgraded from FIGS. 6( f ) and ( g ) respectively as in FIGS. 8( e ) and ( f ).
[0070] Design Key Points: In the same way as in the in-phase mode, the anti-phase mode of the voltage and current conversion type LC combine transformer (see FIG. ( 8 )) is also just the improvement or upgraded from the anti-phase mode of the voltage conversion type LC combine transformer. Hence, its error analysis, design key points, and device selections all are the same as the according contents respectively of the latter stated above, with a difference that the former has functioned as the input and output current anti-phased just one-step further beyond the latter.
3-3. Voltage and Current Conversion-A Type LC Combined Transformer
[0071] Firstly review the current conversion-A type of the LC combined transformer and redraw the circuit diagram in FIG. 3( a ) as in FIG. 9( a ). In FIG. 9( a ), of the Δ or π mutual capacitor consisting of inductances 3 , 9 , 10 , and capacitance 2 , voltage
[0000]
V
=
j
ω
(
I
-
I
h
)
kL
2
=
j
ω
(
I
-
I
2
)
kL
2
-
j
ω
(
I
h
-
I
2
)
kL
2
=
j
ω
(
I
1
-
I
1
n
c
)
kL
2
-
j
ω
(
j
ω
CV
2
)
kL
2
=
j
ω
(
1
-
1
n
c
)
kL
2
I
1
+
ω
2
kL
2
CV
2
=
j
ω
L
s
1
I
1
+
1
n
c
V
2
;
[
L
s
1
=
(
1
-
1
n
c
)
kL
2
]
(
71
)
[0000] From Eqs. (10) and (71), obtain the equivalent circuit, between V and V 2 in FIG. 9( b ), of ideal transformer 22 and in series with its primary winding the equivalent input inductance 21 or L s1 of the mutual capacitor. Next, let's insert a compensation capacitance 23 a or C sa in series connection at point a of input port, or when necessary, insert a compensation capacitance 23 b or C sb in series connection at point b of output port, with their values separately as
[0000]
C
sa
=
1
ω
2
[
(
1
-
k
)
L
1
+
n
2
L
s
1
]
=
1
ω
2
L
1
(
1
-
k
/
n
c
)
(
72
)
C
sb
=
1
ω
2
n
c
2
[
(
1
-
k
)
L
2
+
L
s
1
]
=
1
ω
2
n
c
L
2
(
n
c
-
k
)
(
73
)
[0000] Functions of the circuit in FIG. 9( b ) after compensation can be equivalently expressed as the form of ideal transformers in cascaded connection, with the voltage and current relations as
[0000]
{
V
1
V
2
=
V
1
V
·
V
V
2
=
n
·
1
n
c
=
nkL
2
L
b
+
L
2
(
74
)
I
1
I
2
=
I
1
I
·
I
I
2
=
1
n
·
n
c
=
L
b
+
L
2
nkL
2
(
75
)
[0000] They completely appear as the forms of an ideal transformer's equations, referred to as the voltage and current conversion-A type of the LC combined transformer, or conversion-A ideal transformer or ideal transformer A, when the circuit in FIG. 9 satisfying the condition either of Eqs. (72) and (73).
[0072] Design Key Point: The voltage and current conversion-A type LC combined transformer (FIG. ( 9 )) is just the improvement or upgraded from the current conversion-A type of the LC combined transformer. Hence, its error analysis, design key points, and device selections all are the same as the according contents respectively of the latter stated above, with a difference that the former has functioned as the input and output voltage in-phased just one-step further beyond the latter.
3-4. Current Conversion-A Type LC Combined Transformer
[0073] In the same way, redraw the circuit diagram of the current conversion-B type LC combined transformer in FIG. 4( a ) as in FIG. 10( a ). In FIG. 10( a ), of the Δ or π mutual capacitor consisting of inductances 9 and 10 , and capacitances 2 and 4 , voltage
[0000]
V
=
j
ω
(
I
-
I
h
)
kL
2
=
j
ω
(
I
-
I
2
)
kL
2
-
j
ω
(
I
h
-
I
2
)
kL
2
=
j
ω
(
I
-
I
n
c
)
kL
2
-
j
ω
(
j
ω
C
m
V
2
)
kL
2
=
j
ω
(
1
-
1
n
c
)
kL
2
I
+
ω
2
kL
2
C
m
V
2
=
j
ω
L
s
1
I
+
1
n
c
V
2
;
[
L
s
1
=
(
1
-
1
n
c
)
kL
2
,
when
n
c
≥
1
]
(
76
)
=
j
(
1
-
1
n
c
)
·
1
ω
n
c
C
m
·
I
+
1
n
c
V
2
=
1
j
ω
C
s
1
I
+
1
n
c
V
2
;
(
C
s
1
=
n
c
2
C
m
1
-
n
c
,
when
n
c
<
1
)
(
77
)
[0000] In most cases, there exists n c <1; thus the equation above should be expressed as taking on the series equivalent capacitance C s1 as in Eq. (77) so that in FIG. 10 , the Δ mutual capacitor between V and V 2 can be replaced by an equivalent circuit of ideal transformer 25 and in series with its primary the equivalent input capacitance 24 or C s1 , with the mutual inductor's primary leakage inductance (1−k)L 1 in FIG. 10( a ) being equalized as its secondary leakage inductance (1−k)L 2 in FIG. 10( b ). Next, assume
[0000]
j
ω
(
1
-
k
)
L
2
+
1
j
ω
C
s
1
=
0
,
i
.
e
.
ω
2
(
1
-
k
)
L
2
C
s
1
=
ω
2
(
1
-
k
)
L
2
n
c
2
C
m
1
-
n
c
=
1
,
or
ω
2
(
1
-
k
)
L
2
n
c
2
C
m
=
1
-
n
c
;
[0000] and notice Eq. (20), namely
[0000]
ω
2
L
2
C
m
=
1
kn
c
,
[0000] being substituted in as
[0000]
1
-
k
k
·
n
c
=
1
-
n
c
,
[0000] or say when n c =k, or
[0000]
C
m
C
b
=
1
k
2
-
1
(
78
)
[0000] FIG. 10( b ) could be equivalently replaced as FIG. 10( c ), with the network port voltage and current equations as
[0000]
{
V
1
V
2
=
V
1
V
·
V
V
2
=
n
·
1
n
c
=
nk
(
1
+
C
m
C
b
)
(
79
)
I
1
I
2
=
I
1
I
·
I
I
2
=
1
n
·
n
c
=
C
b
nk
(
C
b
+
C
m
)
(
80
)
[0000] These are also equations of an ideal transformer, which is why the circuit in FIG. 10 , when satisfying condition Eq. (78), is referred to as the voltage and current conversion-B type of the LC combined transformer, or conversion-B ideal transformer or ideal transformer B.
[0074] Design Key Point: The voltage and current conversion-B type LC combined transformer (FIG. ( 10 )) is also just the improvement or upgraded from the current conversion-B type of the LC combined transformer. Hence, its error analysis, design key points, and device selections all are the same as the according contents respectively of the latter stated above, with a difference that the former has functioned as the input and output voltage in-phased just one-step further beyond the latter.
[0000] 4. Function of Waveform Conversion from Square-Wave to Quasi-Sinusoid
[0075] All the three categories or types of the LC combined transformers presented by this invention possess the function of waveform conversion or waveform isolation from square-wave to quasi-sinusoid [Note: take fundamental filter of square-wave as a typical example of waveform conversion, and rectifier transformer as a typical application of waveform isolation]. The following come analysis and explains of only one example for its operating principle and effect [Note: see Appendix III “Functions of Waveform Conversion from Square-Wave to Quasi-Sinusoid of the Mutual Capacitor (Continue)”].
[0076] Let's investigate the working status of the in-phase mode voltage conversion type LC combined transformer in FIG. 5 applied with a supply of cycling or periodic square-wave sequence.
[0077] Assuming that v 1 (t) is a voltage of symmetrical cycling square-wave implemented on the input port of the mutual capacitor, with a cyclic frequency ω=2πf=2π/T and its Fourier's series as
[0000] v 1 ( t )=V 11 sin ω t+V 13 sin 3 ωt+V 15 sin 5 ωt+ . . . +V 1m sin kωt + . . . , ( m= 1,3,5, . . . ) (81)
[0000] where, V 11 , V 13 , V 15 . . . mean the magnitudes of the fundamental, third harmonic, fifth harmonic . . . etc. In addition, the magnitude ratio of m-th harmonic to fundamental for a symmetrical cycling square-wave is V 1m /V 11 =1/m.
[0078] From Eqs. (26) to (28), magnitude of the m-th harmonic of the output voltage V x of the first mutual capacitor in FIG. 5 under the implement of v 1 (t) will be worked out as
[0000]
V
xm
=
V
1
m
[
1
-
m
2
(
1
-
n
v
1
)
]
2
+
[
1
ω
C
m
R
1
(
1
n
v
1
-
1
)
(
1
m
-
m
)
]
2
or
expressed
as
V
xm
V
x
1
=
V
1
m
V
11
·
n
v
1
[
1
-
m
2
(
1
-
n
v
1
)
]
2
+
[
1
ω
C
m
R
1
(
1
n
v
1
-
1
)
(
1
m
-
m
)
]
2
(
82
)
=
1
m
·
n
v
1
[
1
-
m
2
(
1
-
n
v
1
)
]
2
+
[
1
ω
C
m
R
1
(
1
n
v
1
-
1
)
(
1
m
-
m
)
]
2
(
83
)
[0000] By this equation, calculate when n v1 =0.75, 0.5, 0.25, ωC m R 1 =0.1, 1, 2,10, 100, the values of
[0000]
V
xm
V
x
1
[0000] for the mutual capacitor as recorded in the following form:
[0000]
|V xm /V x1 |, when m =
n v1
ωC m R 1
1
3
5
7
9
11
0.75
0.1
1.0000
.0278
.0089
.0042
.0024
.0015
1
1.0000
.1630
.0273
.0093
.0043
.0023
2
1.0000
.1884
.0282
.0095
.0043
.0023
10
1.0000
.1995
.0286
.0095
.0043
.0023
100
1.0000
.2000
.0286
.0095
.0043
.0023
0.50
0.1
1.0000
.0062
.0020
.0010
.0006
.0004
1
1.0000
.0379
.0080
.0029
.0014
.0008
2
1.0000
.0445
.0085
.0030
.0014
.0008
10
1.0000
.0475
.0087
.0030
.0014
.0008
100
1.0000
.0476
.0087
.0030
.0014
.0008
0.25
0.1
1.0000
.0010
.0003
.0002
.0001
.0001
1
1.0000
.0085
.0022
.0009
.0004
.0002
2
1.0000
.0119
.0026
.0010
.0005
.0002
10
1.0000
.0144
.0028
.0010
.0005
.0003
100
1.0000
.0145
.0028
.0010
.0005
.0003
Form 1 List for calculations of |V xm /V x1 | by Eq. (83) when n v1 and ωC m R 1 have different values
[0079] Design Considerations: From the results of the listed data, the influence on the output voltage by the harmonics of fifth and over is almost negligible; the influence of the third harmonic increasing accompanied with increase of n v1 (generally, negligible when n v1 <0.5); the change of (ωC m R 1 ) shows the load carrying capacity of the mutual capacitor not bad, with the load heavier the better fundamental filtering characteristic of the mutual capacitor. However, the heavier load for the mutual capacitor, the worse errors for it will occur determined by Eqs. (29) through (32). Therefore, during designing in practice, balances need to be made on or between the filtering characteristic, the load carrying capacity, and the ratio errors.
5. Utilization of Push-Pull on Inductor
[0080] The utilization of push-pull on inductor is also termed usage of the push-pull inductor. FIG. 11( a ) is a principle scheme and also a trial circuit of the waveform conversion from square-wave to quasi-sinusoid using the circuit either in FIG. 5 or in FIG. 7 . FIG. 11( b ) is an improvement from FIG. 11( a ) by employing the push-pull inductor.
[0081] In FIG. 11( a ), when the control-in terminal P of switch 29 or TR is input the signal with a waveform like P as in FIG. 11( c ), the waveform of input voltage V D of the LC combined transformer is also a single-polar pulsed square-wave sequence in similar with P, while the input current I 1 or I a is a single-polar periodic waveform as well, by which the cores of inductor 1 or L a is magnetized with a locus curve or hysteresis loop as shown in FIG. 11( d ). Within a cycle in steady-state operation of the circuit in FIG. 11( a ), commencing at point Br in FIG. 11( d ) with switch 29 or TR closed and switch 30 or D open while I a increasing, the magnetic flux density, accompanied with the change of the magnetic field strength, moves up the curve V to point a; and then switch 29 or TR open and switch 30 closed as well as I a decreasing, the flux density moves down the curve II back to point Br. This illustrates that the core's magnetization phenomenon occurs only in the first quadrant, which means that the core is not effectively utilized yet.
[0082] To overcome this drawback and make full use of the cores, it will result in a good effect by using a full-bridge or half-bridge circuit to drive the LC combined transformer. However, a bridge circuit has a shortage that it needs a complicated switch-control-and-driving circuit, for the reason that the reference voltages of its two sets of alternately working switches are not at a same potential.
[0083] To achieve this same goal, usage of the push-pull inductor is another choice (see FIG. 11( b )), which includes: {circle around (1)} one center-tapped inductor 1 a or L a ; two sets of electrically-symmetric driving switches such as transistors 31 and 33 [Note 1: Examples for “electrically-symmetric” are as those of driving switches, passive switches and their driving signals etc in double-ended circuits such as half-bridge, full-bridge and push-pull converters. Note 2: Suppose that the circuit herein belongs to positive logic and employs npn bipolar junction transistors (BJTs) though this application is not limited on positive logic nor to bipolar transistors employed only]; two sets of electrically-symmetric passive switches such as diodes 32 and 34 ; with the value and current rating of inductance L a , and electrical specifications of the switches all determined by the requirements of design. {circle around (2)} one end of inductor 1 a electrically connected to the collector of transistor 31 and also to the anode of diode 32 , the other end of 1 a to the collector of transistor 33 and also to the anode of diode 34 , the emitters of transistors 31 and 33 electrically connected together to the reference level, the cathodes of diodes 32 and 34 electrically connected together to high level of the source, the center-tap of inductor la to an appropriate level [Note: In this example, to the junction between capacitances 2 and 4 ], the bases or control-in terminals of transistors 31 and 33 separately connected to corresponding control-and-driving signals with two periods as a cycle, electrically-symmetrical to each other and alternately working. {circle around (3)} the push-pull inductor employing a technique of the bi-periodically time-shared driving as described as: the PWM control-and-drive signals for switches 31 and 33 in FIG. 11( b ) separately be chosen as those like P 1 and P 2 as shown in FIG. 11( c ); although the total current, I a in FIG. 11( b ), of the push-pull inductor remains the same as in FIG. 11( a ), the magnetization mode of the cores of inductor 1 a or L a is changed (see FIG. 11( e )) as: during the steady-state operation of the circuit in FIG. 11( b ), when only switch 31 or TR 1 turned on, the core's magnetization locus goes up curve I from point −Br to point a; then switch 31 or TR 1 turned off and diode 32 or D 1 turned on, while magnetizing down curve II from point a back to point Br till no later than the moment that the first period of the circuit operation ends; symmetrically, the second period starts when only switch 33 or TR 2 turned on, the cores' magnetizing continuously moving down curve III from point Br to point b; thereafter, switch 33 or TR 2 turned off and diode 34 or D 2 turned on, while the locus going up curve IV from point b back to point −Br till no later than the end of the second period of the circuit operation and also of one cycle of the bi-periodically time-shared driving [Note: Herein the working sequence of switches is described by investigating the cores' magnetization loci; it also can be described simply by stating the switch operations as: switch 33 being off for the first period while switch 31 on not longer than T/2 before turning off; for the second period switch 31 being off while switch 33 on not longer than T/2 before turning off, with the end of second period as the end of a cycle of the bi-periodically time-shared driving; where T is the time of switch operating period of the circuit].
[0084] In this example, the inductance value of inductor 1 a in FIG. 11( b ) is equal to that of inductor 1 in FIG. 11( a ). In most cases, inductor 1 a may use same cores and share the same coil turns number as those for inductor 1 , with the differences that, two coils of N turns, if N is the coil turns number for inductor 1 , wound bifilarly in parallel or separately in sections; and the wire cross-sectional area of the 1 a coils equal to half that of 1 's; and the wound twin coils connected series-aiding, with the connected point as the center-tap.
[0085] The technique of bi-periodically time-shared driving, in the utilization of push-pull on inductor, extends the cores' magnetization as widely as to all four quadrants, or full range of its magnetization characteristic, greatly upgrading its effectiveness, and with its size relatively decreased as well as the loss and cost accordingly declined. In addition, it eliminates problem of the cores' unsymmetrical magnetization phenomenon in conventional push-pull driving mode and greatly alleviates the cross-conductance of driving switches. Therefore, this technique is also suited for driving any other double-ended circuits, including bridge, half-bridge, and conventional push-pull, etc. As well, the usage of push-pull inductor, besides for the mutual capacitor or the LC combined transformer, could be exploited in other circuits, such as in active power factor correction (APFC) circuit, and the like.
Postscript
[0086] Although this description, Appendixes included, contains numerous details and specificities, it is to be understood that these are merely illustrative of the present invention, and are not to be constructed as limitations. Many modifications will be readily apparent to those skilled in the art, which do not depart from the spirit and the scope of the invention, as defined by the appended claims and their legal equivalents. | This invention presents the LC combined transformer, a combination of capacitances, inductances and an electrically-isolated mutual inductor, i.e. conventional transformer. To improve the imperfections of the widely-used transformers, by means of the simplest passive-circuit design of perfectly-functionally mating mutual capacitors with the mutual inductor, the invention achieves optimal characteristics of current or/and voltage conversions, with a new property of waveform conversion from square-wave to quasi-sinusoid. The ideal current transformers herein are suited to sinusoidal current measurements, the ideal voltage transformers suited to sinusoidal voltage measurements, and they all could be upgraded to ideal transformers, capable of current and voltage conversions. They can also be designed as both power transferable and waveform convertible, applicable in power electronics. Herein also states the design approach of integrated inductor and mutual inductor and the usage of push-pull inductor, materials being fully utilized and sizes greatly decreased. | 7 |
RELATED APPLICATIONS
[0001] This application is related to PCT publications and applications WO99/62415, WO00/56226, WO00/56227, PCT/IL00/00611, WO00/56228, PCT/IL00/00609 and PCT/IL01/00074, all of which designate the US, the disclosures of which are incorporated herein by reference. This application also claims the benefit under 119 (e) of 60/254,689, the disclosure of which is incorporated herein by reference. This application is also related to an application titled “GRAFT AND CONNECTOR DELIVERY”, filed on even date by same applicant in the Israel receiving office of the PCT, the disclosure of which is incorporated herein by reference.
[0002] The present invention relates to performing anastomotic connections, for example, via a vascular system.
BACKGROUND OF THE INVENTION
[0003] Bypass procedures, in which a clogged vessel, for example in the heart, is bypassed by an unclogged conduit, are well known in the art. Recently, the desirability of performing this procedure using a vascular approach, has come to prominence, at least because the surgical wound is less traumatic to the patient. This procedure is known as a transvascular procedure.
[0004] In a transvascular procedure, however, there is a danger that the various tools and devices, which are provided through a catheter, will be damaged by or damage the catheter and/or be deployed incorrectly.
[0005] A competing method is operating through a small hole in the chest, a mini-thoractomy. However, this method cannot generally be used where there are more than two vessels to bypass, as is often the case.
SUMMARY OF THE INVENTION
[0006] An aspect of some embodiments of the invention relates to protecting a delivery catheter and tools being delivered via the catheter during a bypass procedure. In an exemplary embodiment of the invention, a protective sheath is provided for enclosing a punch, prior to and/or after the punch transfixes the tissue to be punched. Alternatively or additionally, a same or different protective sheath is provided for enclosing and, optionally assisting in deployment, of an anastomotic connector.
[0007] Alternatively, in an exemplary embodiment of the invention, an outer cutting tube of a punch is used as the protective sheath for the punch.
[0008] Optionally, the sheath is more rigid at its distal end, where it protects the tool.
[0009] Optionally, the sheath is shaped to aim the tools to be perpendicular (or at any other desired angle) to the wall of the blood vessel from which the procedure is performed, for example, an aorta
[0010] An aspect of some embodiments of the invention relates to a guide for deployment of an anastomotic device. In an exemplary embodiment of the invention, the guide comprises a plurality of receptacles for maintaining bent back spikes of an anastomotic connector in a radially compressed and/or pulled back position. In an exemplary embodiment of the invention, the tips of the spikes are bent, even if the body of the spike is straightened for delivery. Optionally, the guide prevents the connector from pulling itself out prematurely, for example, if front spikes of the connector engage nearby tissue. Optionally, the guide also restrins front spikes of the connector. In some embodiments, the receptacle comprises an inner lip in the guide, possibly allowing the connector some axial motion, until the back spikes hit the lip. This allows the front spikes of the connector to exit and engage nearby tissue, without pulling the whole connector out of the guide. Alternatively, the receptacle comprises holes for holding the tips of the spikes. Optionally, the receptacle comprises a capsule that is closed at one end. In an exemplary embodiment of the invention, the spikes comprise 3, 4, 5, 6 or a greater or fewer number of spikes.
[0011] In an exemplary embodiment of the invention, the guide includes a flaring out section distal of the receptacles.
[0012] Only when the guide exits a hole in an aorta, the flaring out portion spreads out, freeing the back spikes to engage the aorta A similar mechanism may be used for entering a blood vessel, for example a coronary vessel, in which the flaring out occurs inside the free volume of the vessel, freeing back and/or front spikes of the connector. In an exemplary embodiment of the invention, the flaring out portion comprises a tube with axial splits. Possibly, a balloon or other expanding device is used to force the flaring. Alternatively, the tube may be pre-stressed to flare out when released.
[0013] Alternatively, the bent part of the spike is held between two elements such as tubes and/or elongate members. In one exemplary embodiment of the invention, the two elements define at their tip a receptacle for the bent spike tips (e.g., perpendicular to the guide axis). Alternatively, the two elements hold the spike by radial pressure. Optionally, at least one of the elements includes a slot or window for receiving the bent portion of the back spike.
[0014] In an exemplary embodiment of the invention, the guide comprises a capsule with one closed end. Optionally, the connector is held by inserting an inner mandrel (or object, such as a bead) between the backward spikes.
[0015] An aspect of some embodiments of the invention is an anti-dislodgement mechanism for a catheter tip that is inserted into (and/or out of) a hollow organ, for example a blood vessel, through an entry hole. In an exemplary embodiment of the invention, the catheter, at least at its tip, includes two layers connected at their tips, namely an inner tube and an outer, axially slit tube. When the inner tube is retracted concurrently with maintaining the outer tube in place, the slit portion of the outer tube flares out to have a diameter greater than that of the entry hole, for example, twice or three times the radius, so that the catheter cannot be retracted.
[0016] An aspect of some embodiments of the invention relates to a guided punch. In an exemplary embodiment of the invention, a hole is punched in a vessel, for example an aorta, by penetrating the aorta with a thin guide wire and then advancing the punch over the guide wire. Optionally, an intermediate thickness tube is advanced into the hole formed by the guide wire, prior to advancing the punch. Optionally, the intermediate tube has a blunt end and is used to enclose the tip of the guide wire and prevent inadvertent puncturing of other body tissues. Optionally, the guide wire is retracted after it is used to penetrate the aorta, so that only the less sharp objects (e.g., the punch tip) are extended. The punch may be, for example, a rotating cutting punch or a axially moving punch.
[0017] An aspect of some embodiments of the invention relates to a rotating punch mechanism. In an exemplary embodiment of the invention, the punch comprises a central guide portion and a surrounding outer cutting tube. An inner diameter of the cutting tube defines the diameter of the cut. In an exemplary embodiment of the invention, the central guide portion, for example, a thin guide-wire like portion, is inserted into the target tissue to be punched Possibly, the central guide portion includes a stop to prevent over-penetration of the guide portion. The cutting tube is then pushed against the target tissue and rotated around the guide portion to cut out a section of the tissue. Optionally, the outer tube is coupled to the central guide, so that it is advanced with it. Alternatively or additionally, the outer tube is elastically urged against the target tissue. Alternatively or additionally, the outer tube is manually advanced.
[0018] Optionally, the cutting tube advances as it rotates, for example, on a screw. Optionally, he advance is limited to a fixed amount, for example, to be less or somewhat more than the thickness of the punched vessel, for example, between 3 mm and 9 mm for an aorta.
[0019] An aspect of some embodiments of the invention relates to an anastomosis connector having a plurality of non-penetrating spikes, each of which is formed by the meeting, at an angle, of two arms. Optionally, the plurality of spikes is merged into a single unit In an exemplary embodiment of the invention, the connector comprises a cylindrical or ring body 5 having, at one end thereof, a plurality of non-penetrating spikes. In an exemplary embodiment of the invention, the spikes are merged into an undulating curve, curved areas of which act as the spike parts in contact with vascular tissue. In an exemplary embodiment of the invention, the curve serves to apply pressure to a wall of a blood vessel (e.g., an aorta), that is perpendicular to the central axis of the connector. Optionally, the spikes are designed to bend (e.g., by locally weakening the connector) or are pre-bent at at least two locations. One bend location causes part of the curve to lie perpendicular to the cylinder axis. A second bend location causes the rest of the curve to lie at a sharp angle to the cylinder axis. In an exemplary embodiment of the invention, the spikes are curved in the bending plane so that they can better apply pressure to a perpendicular blood vessel wall.
[0020] In an exemplary embodiment of the invention, the curve defines areas of higher curvature, which areas twist when the spikes are deployed. Alternatively, a torsion bar is provided at points of high twisting. Alternatively or additionally, two or more torsion bars and/or torsion joints are provided in series. In one example, a spike is bent 180° by providing two torsion bars or joints, one for each bend. In an exemplary embodiment of the invention, each torsion area is defined by two arms that define the ends of the bar. In an exemplary embodiment of the invention, the spike comprises two arms that meet a torsion bar and two more arms extend from the torsion bar, and meet at a second torsion bar. One or more arms extending from the second bar define the tip of the spike (or another torsion bar). Alternatively, a torsion bar or area is defined between two arms that meet at an angle or at a slight offset (e.g., with the twist area being defined in the offset).
[0021] An aspect of some embodiments of the invention relates to loading of an anastomosis connector into a delivery system used for a vascular approach. In one example, the delivery system comprises a tube that encloses at least part of the connector. In an exemplary embodiment of the invention, the connector has a set of forward pointing spikes and a set of backwards pointing spikes and the connector is mounted by bending back the backwards set of spikes and restraining the backwards spikes in the delivery system. Optionally, however, the bent tips of the backwards spikes remain bent. The forward spikes are optionally not bent backwards, for example being restrained by the delivery system or sticking out of the delivery system.
[0022] In an exemplary embodiment of the invention, the backwards spikes are bent back by enclosing each spike in a flexible tube and pulling the tubes through the delivery system. Alternatively, the spikes are bent back with a tool that bends the spikes back to fit into tube of the delivery system.
[0023] In an exemplary embodiment of the invention, the connector is held, in the delivery system, between an inner and an outer tube. In an exemplary embodiment of the invention, the connector is held using a pre-defined bend in the backwards spikes of the connector. In an exemplary embodiment of the invention, the inner and outer tube define a step that engages the bent tip of the spikes. Alternatively or additionally, the inner tube defines a slot that receives the bend area itself.
[0024] An aspect of some embodiments of the invention relates to the injection of contrast material during a bypass procedure. In an exemplary embodiment of the invention, a catheter is provided in an aorta or other large vessel and then exits the vessel to perform a bypass. In an exemplary embodiment of the invention, the catheter comprises a sheath, optionally bent to lay perpendicular to the aorta, and an inner punch mechanism. Optionally, the punch mechanism includes an inner sheath. Optionally, the punch mechanism is replaced by a graft delivery system. In an exemplary embodiment of the invention, injection of contrast material is used to determine that the catheter is near the aorta wall. In an exemplary embodiment of the invention, the catheter is aimed so that when it exits the aorta, it will enter fatty tissue rather than cardiac tissue. Imaging may be, for example, using X-ray fluoroscopy, CT or open MRI.
[0025] Alternatively or additionally, contrast material is injected outside the aorta In an exemplary embodiment of the invention, the thickness of the aorta is measured by imaging the area and measuring the distance between different areas with contrast material. Alternatively or additionally, the external contrast material is used as a landmark for determining how far to advance the punch, graft and/or a connector on the graft. Alternatively or additionally, contrast material is injected into the graft, from the aorta, to detect leaks.
[0026] In an exemplary embodiment of the invention, the catheter system includes multiple ports for contrast material (e.g., in the catheter handle), including: in the sheath (outside of the punch), in the punch and optionally in the inner sheath of the punch. Optionally, one or more dedicated contrast material channels are provide din the catheter, for example, as separate tubes.
[0027] An aspect of some embodiments of the invention relates to utilizing the venous coronary system for providing arterial blood to the heart. In an exemplary embodiment of the invention, the coronary sinus is blocked and the coronary sinus and/or one of the veins leading to it are connected, possibly via a bypass conduit, to the arterial system, for example to the aorta or to a mammary artery. It is expected that the veins will provide blood to the heart, possibly becoming more artery-like as time goes on. Optionally, one of the veins is disconnected from the coronary sinus and connected, possibly via a bypass conduit, to the vena cava or another part of the venous system, to provide drainage from the coronary vascular system.
[0028] There is thus provided in accordance with an exemplary embodiment of the invention, an anastomosis delivery system for delivering a connector having at least one backwards spike having a bent tip, comprising:
[0029] a hollow guide sheath; and
[0030] a hollow, axially slotted section, fitting within said sheath, said section having a flared configuration and an unflared configuration and wherein said axially slotted section is adapted to contain at least a part of said connector and to limit axial motion of said connector when said section is in its unflared configuration. Optionally, axially moving said section selectively advances said spike. Alternatively or additionally, axially moving said section selectively retracts said spike.
[0031] In an exemplary embodiment of the invention, said slotted section maintains said bent tip in a bent configuration.
[0032] In an exemplary embodiment of the invention, said slotted section includes at least one receptacle for engaging said bent tip. Optionally, said receptacle comprises an inner lip of said section, adapted for catching said tip. Alternatively or additionally, said receptacle comprises a hole in said section, for engaging said tip.
[0033] In an exemplary embodiment of the invention, said section comprises a second, inner tube and wherein said inner tube and said slotted section define between them a receptacle for a bent section of at least one bent spike of connector. Optionally, said receptacle is a space between tips of said slotted section and said inner tube.
[0034] In an exemplary embodiment of the invention, said receptacle is an opening in said inner tube. Alternatively or additionally, said slotted section and said inner tube grip between them a part of said connector.
[0035] In an exemplary embodiment of the invention, said slotted section comprises a capsule closed at one end.
[0036] There is also provided in accordance with an exemplary embodiment of the invention, an anastomosis delivery system for delivering a connector having at least one backwards spike having a bent tip, comprising:
[0037] a hollow guide sheath;
[0038] an apertured inner tube fitting within said sheath; and
[0039] a plurality of spike locking elements disposed between said guide sheath and said apertured inner tube, wherein said spike locking elements, when extended, are adapted to grip a part of said anastomosis connector between said inner tube and said locking elements and wherein said apertures are each adapted to receive a said bent tip of said anastomosis connector.
[0040] There is also provided in accordance with an exemplary embodiment of the invention, an anastomosis delivery system for delivering a connector having at least one backwards spike having a bent tip, comprising:
[0041] a hollow guide sheath;
[0042] a cylindrical capsule having one open end an one closed end; and
[0043] an anastomosis connector held in said capsule. Optionally, the system comprises a stopper arranged between a plurality of said backwards spikes and urging said spikes towards said capsule
[0044] There is also provided in accordance with an exemplary embodiment of the invention, a method of mounting an anastomosis connector having a plurality of bent backwards spikes including bent tips, into a delivery tube, comprising:
[0045] bending back said spikes to point backwards along an axial direction of said connector, away from a graft mounted on said connector;
[0046] maintaining said tips in a bent configuration; and
[0047] inserting said spikes into a receptacle of said delivery tube, which receptacle maintains said tips in a bent configuration.
[0048] Optionally, bending back comprises:
[0049] mounting a thin flexible tube on each of said spikes;
[0050] threading said tube through a plurality of tip holding apertures in said receptacle; and
[0051] retracting said tubes to bend said spikes and pull them into said receptacle. Optionally, the method comprises:
[0052] locking said connector in place; and
[0053] retracting said tubes to remove them from said spikes.
[0054] Additionally, bending back comprises:
[0055] pushing back each spike, using a jig, into said receptacle; and
[0056] locking said spike tip in said receptacle.
[0057] There is also provided in accordance with an exemplary embodiment of the invention, a guided punch, comprising:
[0058] a sharp, extendible guide wire; and
[0059] a hollow punch mechanism adapted to ride on the guide wire, wherein said guide wire is adapted to extend from said punch. Optionally, said guide wire has a limited extension distance of less than 3 cm. Optionally, said distance is shorter than 1 cm. Optionally, said distance is greater than 0.3 cm.
[0060] In an exemplary embodiment of the invention, said punch comprises a hollow tube adapted to fit between said punch mechanism and said guide wire.
[0061] In an exemplary embodiment of the invention, said punch is a rotating punch
[0062] In an exemplary embodiment of the invention, said punch is an axially moving punch.
[0063] In an exemplary embodiment of the invention, said punch is adapted for injection of contrast material inside of said hollow of said punch mechanism.
[0064] There is also provided in accordance with an exemplary embodiment of the invention, a rotating punch, comprising:
[0065] a sharp, central guide wire; and
[0066] a rotating outer tube having a vascular cutting edge defined by a lip of said tube. Optionally, said outer tube advances as it is rotated. Optionally, said advancing is limited to less than 3 cm. Optionally, said advancing is limited to less than 1 cm.
[0067] In an exemplary embodiment of the invention, said punch is adapted for a particular target vessel, by matching said advancing limitation to the target vessel.
[0068] In an exemplary embodiment of the invention, said cutting edge is smooth. Alternatively, said cutting edge is serrated.
[0069] In an exemplary embodiment of the invention, said guide wire is smooth. Alternatively, said guide wire is adapted to engage vascular tissue it is inserted into.
[0070] In an exemplary embodiment of the invention, the punch comprises a hollow tube adapted to be brought over said guide wire and within said rotating outer tube. Optionally, said punch is adapted for injection of contrast material inside of said hollow tube.
[0071] In an exemplary embodiment of the invention, said punch is adapted for injection of contrast material between said spike and said outer tube.
[0072] In an exemplary embodiment of the invention, said outer tube is bent at a right angle, such that positioning perpendicular to a vessel wall is assisted. Alternatively or additionally, said outer tube has an increasing outer diameter, away from said cutting edge.
[0073] In an exemplary embodiment of the invention, the punch comprises a balloon distal from said cutting edge, said balloon, when inflated, having an outer diameter slightly greater than a diameter of said outer tube and about the inner diameter of a sheath associated with said punch.
[0074] There is also provided in accordance with an exemplary embodiment of the invention, an advancing rotating punch, comprising:
[0075] a sharp, central guide wire; and
[0076] a rotating outer tube adapted to cut a target vessel which advances relative to said wire when it rotates.
[0077] There is also provided in accordance with an exemplary embodiment of the invention, a catheter system, comprising:
[0078] an outside sheath having an inner volume;
[0079] a first contrast injection port communicating with the inner volume of said sheath;
[0080] at least one inner mechanism conveyed by said sheath and having an inner volume; and
[0081] a second contrast injection port communicating with the inner volume of said inner mechanism. Optionally, said at least one inner mechanism comprises two switchable inner mechanisms. Alternatively or additionally, said at least one inner mechanism comprises an inner tube and said system comprises a third contrast injection port associated with said inner tube. Alternatively or additionally, said sheath is bent to facilitate perpendicular positioning of a tip of said sheath against an inner wall of a target blood vessel. Optionally, inner mechanism is bent to match said bend in said sheath. Alternatively or additionally, said system comprises a straight guide wire adapted to fit in said sheath and maintain said sheath straight when said sheath is guided to a target area.
[0082] In an exemplary embodiment of the invention, said at least one inner mechanism comprises a punch. Optionally, said system comprises an inner tube having a diameter that varies, along its length between a diameter of said punch and an inner diameter of said sheath.
[0083] In an exemplary embodiment of the invention, said system comprises balloon distal of said punch and having a diameter that varies between a diameter of said punch and an inner diameter of said sheath.
[0084] There is also provided in accordance with an exemplary embodiment of the invention, an anastomotic connector, comprising:
[0085] a cylinder-like body, and
[0086] at least one set of spikes, coupled to said body by twisting joints. Optionally, said spikes are adapted not to penetrate tissue which the spikes contact. Optionally, said twisting joints comprise at least one torsion bar. Alternatively or additionally, said twisting joints comprise at least one bend area. Alternatively or additionally, said set of spikes are bent. Optionally, said set of spikes are bent at two different locations along the spikes. Alternatively or additionally, each spike comprises two arms that meet at a tip of the spike and are each attached to a different part of said connector. Optionally, each arm is attached to a base extension of said connector, by a twisting joint. Optionally, said arms and said base extensions define a continuous curve.
[0087] There is thus provided in accordance with an exemplary embodiment of the invention, a fixating guide sheath for insertion into a blood vessel, comprising:
[0088] an inner tube; and
[0089] an outer tube, slotted near an end thereof, wherein said inner tube is retracted relative to said outer tube, said slotted outer tube flares out to prevent further retraction of said sheath. Optionally, said sheath is bent near said end.
BRIEF DESCRIPTION OF TEE DRAWINGS
[0090] Non-limiting embodiments of the invention will be described with reference to the following description of exemplary embodiments, in conjunction with the figures. The figures are generally not shown to scale and any measurements are only meant to be exemplary and not necessarily limiting. In the figures, identical structures, elements or parts which appear in more than one figure are preferably labeled with a same or similar number in all the figures in which they appear, in which:
[0091] FIGS. 1 - 15 illustrate a process of performing a proximal transvascular anastomosis, in accordance with an exemplary embodiment of the invention;
[0092] [0092]FIG. 16 illustrates a capsule for guiding the delivery of an anastomosis connector, in accordance with an exemplary embodiment of the invention;
[0093] [0093]FIG. 17 illustrates an alternative catheter delivery system, including a separate protective sheath, in accordance with an exemplary embodiment of the invention;
[0094] FIGS. 18 - 22 illustrate a guided punch, in accordance with an exemplary embodiment of the invention;
[0095] [0095]FIGS. 23A and 23B illustrate an anti-dislodgment mechanism for a catheter, in accordance with an exemplary embodiment of the invention;
[0096] [0096]FIG. 24A illustrates a rotating and cutting out punch mechanism, in accordance with an exemplary embodiment of the invention;
[0097] FIGS. 24 B- 24 D show an exemplary rotating punch, in accordance with an exemplary embodiment of the invention;
[0098] FIGS. 24 E- 24 F show an alternative rotating punch, in accordance with an exemplary embodiment of the invention;
[0099] [0099]FIG. 25 illustrates a device delivery guide, as an alternative to the capsule shown in FIG. 16, in accordance with an exemplary embodiment of the invention;
[0100] [0100]FIG. 26 is an exploded view of the guide system of FIG. 25;
[0101] FIGS. 27 A- 27 C illustrate two exemplary anastomosis connectors, in accordance with an exemplary embodiment of the invention;
[0102] FIGS. 28 A- 28 B illustrate a method of mounting a connector, such as the connector of FIG. 27, into a delivery system, in accordance with an exemplary embodiment of the invention;
[0103] FIGS. 29 A- 29 D show a method of mounting a connector, in accordance with an alternative exemplary embodiment of the invention; and
[0104] FIGS. 30 A- 30 C show details of the process of attaching the connector of FIG. 27 to an aorta, in accordance with an exemplary embodiment of the invention
DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS
[0105] In a transvascular procedure at least part of the procedure is performed via a catheter. In one example, the provision of a graft and/or its attachment to a source artery are performed via a catheter. The other side of the anastomosis, for example, may be performed via the same or a different catheter and via a same or different vessel or it may be performed using a more invasive technique, such as open surgery or (mini-) thoractomy. In an exemplary embodiment of the invention, the transvascular technique is used to provide grafts for multiple bypass operations, with one or more mini-thoractomy openings being used to attach the grafts to target coronary vessels.
[0106] Although the following description focuses on the heart, the following devices and/or procedures may be used for other organs and bypass procedures as well, as appropriate.
[0107] FIGS. 1 - 15 illustrate a process of performing a proximal transvascular anastomosis, in accordance with an exemplary embodiment of the invention. In this process, a catheter is brought against the inside of an aortic wall, a hole is punched out of an aorta, the catheter is advanced into the punched out hole, an anastomosis connector mounted on a graft is positioned in the hole and then the catheter is retracted and the connector is deployed.
[0108] In an exemplary embodiment of the invention, catheter 100 is a J-tip catheter. Optionally, a rigid stylet is used for insertion and/or navigation of the catheter.
[0109] [0109]FIG. 1 shows a guiding catheter 100 , being brought against an inside wall of an aorta 102 at a location 104 thereof. A punch mechanism provided inside catheter 100 includes a needle punch 106 having a punch area 112 adapted to receive tissue to be punched out and an outer punch tube 108 which cooperates with needle punch 106 to cut off the received tissue. Optionally, a balloon 110 is provided proximal of needle punch 106 . Its use, and that of an alternative mechanism, will be described below. Catheter 100 may include a hemostat valve, to prevent blood leakage.
[0110] As shown in FIG. 1, during feeding of the punch mechanism, outer tube 108 is optionally brought forward (or needle punch 106 kept retracted relative to the outer tube) over the tip of needle punch 106 , to prevent the tip from inadvertently engaging catheter 100 , aorta 102 and/or other nearby tissues or devices.
[0111] In an exemplary embodiment of the invention, catheter 100 includes a bend, to support correct angular orientation to the aorta wall. Optionally, the punch includes a matching bend. In an exemplary embodiment of the invention, the catheter is inserted in a straight manner and when a guide wire or stylet is removed from the catheter, it reverts to its bent orientation. Contrast material may also be injected before the stylet is removed, to allow the position of catheter 100 to be determined. In an exemplary embodiment of the invention, the catheter is oriented in a direction that ensures that there is no critical and/or sensitive tissue right outside the aorta, where it might be damaged by the bypass procedure.
[0112] In an exemplary embodiment of the invention, contrast material (e.g., x-ray, CT, MRI or ultrasound contrast material) is injected through catheter 100 to ensure that its tip contacts the wall if the catheter is close enough to the wall, the profile of the wall and of the catheter are expected to show up in the image. It should be noted that due to the fast flow in the aorta, it may be desirable to time the imaging to the provision of the contrast.
[0113] In FIG. 2, needle punch 106 is brought up against location 104 and outer tube 108 is retracted.
[0114] In FIG. 3, needle punch 106 is advanced through aorta 102 , so that the wall of the aorta is received in punch area 112 . Optionally, this penetration is sensed (manually) or seen, for example by injecting contrast material into catheter 100 and viewing the relative location of punch 106 and the wall.
[0115] As described below, punch 106 may comprise a sharp tip that once inserted is replaced by or covered by an over tube that is less sharp. In an exemplary embodiment of the invention, contrast material is injected out of the aorta through the punch or through the sheath, to ensure the punch is outside the aorta. Alternatively or additionally, contrast material is injected between the sheath and the punch. Comparing the two sets of injections allows a determination of the thickness of the aorta wall.
[0116] In FIG. 4, outer tube 108 is advanced through aorta 102 and past punch area 112 , where it cuts out the received portion of the aorta. Optionally, outer tube 108 is advanced past the tip of needle punch 106 , to protect tissue outside the blood vessel (or inside, for inward punching) from being damaged by the tip. In an inward punching embodiment, it is the blood vessel wall, away from the punch location that is protected. Optionally, the motions of needle punch. 106 and outer tube 108 are coupled so that a user needs to operate only a single control. In one example, the advance of needle punch 106 a certain distance (e.g., through the aorta), releases a spring loaded mechanism that advances outer tube 108 past the tip of needle punch 106 . Alternatively, a less automatic mechanisms may be used, for example one in which stops are provided in the controls, so that manual motion of the needle punch and/or the outer sleeve is stopped by the stop when a desired relative position is achieved. Alternatively or additionally, suitable markings for the different tubes are provided in the part of the delivery system outside the body. In one example, the handle of catheter 100 and/or the proximal end of outer tube 108 are transparent or slotted, so the relative locations of the needle punch tube (its proximal end) and/or the outer tube, can be seen. Such mechanisms may optionally be used for the methods shown in the other figures.
[0117] In FIG. 5, balloon 110 is positioned to be inside the hole in the aorta. This is an optional procedure, used to assist in inserting the catheter 100 into the hole in the aorta. Balloon 110 may be fixed to needle punch 106 . Alternatively, it may be conveyed over the length of the proximal part of needle punch 106 .
[0118] In FIG. 6, outer tube 108 is retracted, leaving balloon 110 in contact with the aorta, sealing the hole in the aorta.
[0119] In FIG. 7, balloon 110 is inflated, expanding the opening in the aorta to be slight less, the same or even greater than the diameter of catheter 100 . Optionally, the tip of outer tube 108 is not sharp, at least not on its inside edge. This may prevent the balloon from being damaged by the edge of tube 108 .
[0120] In FIG. 8, catheter 100 is advanced through the opening in aorta 102 . Optionally, balloon 110 is inflated to engage catheter 100 , so the two are advanced as one. Alternatively, catheter 100 is advanced over balloon 110 .
[0121] In FIG. 9, balloon 110 is deflated.
[0122] In FIG. 10, needle punch 106 is retracted with balloon 110 , leaving catheter 100 transfixing the aorta
[0123] [0123]FIG. 11 shows a second stage of the anastomosis process in which a graft 122 (e.g., a vein, harvested artery or other graft type) is attached to aorta 102 at location 104 . A guide wire 120 is optionally used for conveying graft 122 through catheter 100 and/or for navigation to the target vessel (not shown) various methods may be used for navigation, including, without limitation, X-ray fluoroscopy, ultrasound and MRI. Optionally, catheter 100 and/or other parts of the delivery system and/or portions thereof are made radio-opaque (or ultrasound reflecting) to assist in imaging the procedure.
[0124] Optionally, the contrast material that was previously injected outside the aorta is used as a reference for determining how far to advance the graft and/or connectors.
[0125] In an exemplary embodiment of the invention, graft 122 is provided attached to a connector 124 . However, in other embodiments, the connector or the graft may be provided separate. In an exemplary embodiment of the invention, connector 124 is restrained in a delivery capsule 126 , optionally using a holder 128 .
[0126] In FIG. 11, capsule 126 is positioned so that the connector is inside the hole in aorta 102 .
[0127] In FIG. 12, catheter 100 is retracted, leaving capsule 126 engaged by aorta 102 . Possibly, this engagement is strong enough to prevent some or all leaks out of aorta 102 .
[0128] In FIG. 13, connector 124 is advanced relative to capsule 126 , for example by advancing guide wire 120 , which may be coupled to holder 128 . A plurality of forward spikes 130 of connector 124 are thus freed from capsule 126 Optionally, capsule 126 is retracted alternatively or additionally to the advancement of connector 124 .
[0129] In FIG. 14, capsule 126 is retracted with connector 124 , so that spikes 130 are pulled into the wall of aorta 102 .
[0130] In FIG. 15, capsule 126 is further retracted, without connector 124 , so that a plurality of backward spikes 132 of connector 124 are freed to engage aorta 102 . The connection between aorta 102 and graft 122 is now complete. The other end of graft 122 may be connected to a target vessel in various manners, including by applying the same process in an opposite direction at the target vessel or through a mini-thoracic or keyhole opening.
[0131] Optionally, contrast material is injected into the graft and/or in the aorta near the graft. Such an injection allows to detect leaks from the connection or from the graft and/or to view the placement of all the connector legs relative to the aorta wall.
[0132] Two optional fat beads 134 and 136 , that are fixed on guide wire 120 , are shown. They may be used, for example, for radio-opaque imaging based techniques, such as fluoroscopy, to aid in verifying position and/or navigating. Alternatively or additionally, bead 134 may be used to apply force to holder 128 and/or keep it inside capsule 126 . Holder 128 may, in different embodiments, be freely moving, coupled to guide wire 120 , coupled to capsule 126 or riding on guidewire 120 , with a ratchet mechanism that allow one direction of motion only. In an exemplary embodiment of the invention, holder 128 is a disk.
[0133] [0133]FIG. 16 illustrates a capsule 200 for guiding the delivery of an anastomosis connector, in accordance with an exemplary embodiment of the invention. This capsule may be used in place of capsule 126 , in place of holder 128 and/or in addition to one or both of the parts, in different embodiments. As shown capsule 200 is formed of a slotted tube 202 , in which the slots define a plurality of wings 204 , which can swing out radially. Each wing has an inner rim 206 or other means for maintaining a tip of spike 130 in place. In an exemplary embodiment of the invention, capsule 200 releases spikes 130 , when the wings exit (e.g., are pushed out) from capsule 126 and/or from aorta 102 (if there is no capsule).
[0134] [0134]FIG. 17 illustrates an alternative delivery catheter system, including a separate protective sheath 250 , within catheter sheath 100 , in accordance with an exemplary embodiment of the invention. In this embodiment, a separate retractable/advancable sheath 250 is used to protect catheter 100 from punch 106 . Optionally, sheath 250 is also used for guiding connector 124 , as explained below in FIG. 25. The use of a balloon is optional, for example a thickening of the punch outer tube may replace the balloon, as described herein.
[0135] FIGS. 18 - 22 illustrate a guided punch, in accordance with an exemplary embodiment of the invention. The punch comprises a punch tip 400 , which cooperates with a punch base 406 , to remove a section of aorta 102 .
[0136] In an exemplary embodiment of the invention, punch tip 400 is hollow, so that a sharp guide wire 402 can be extended there-through A pilot puncture in aorta 102 is made by wire 402 . It should be noted that punch tip 400 does not then include a very sharp tip, so a protective sheath mechanism may be avoided, in some embodiments of the invention. The degree of extension of guide wire 402 may optionally be limited to the (expected) thickness of the aorta or less, in which case needle punch 400 is preferably brought against aorta 102 before guide wire 402 is extended. Alternatively, the extension is greater than the thickness, to ensure penetration of the aorta, for example, being between 3 mm and 10 mm. As noted above, contrast material may be injected through the sheath, to determine the aorta thickness.
[0137] In FIG. 19, an optional tube 404 is advanced over the guide wire and through the aorta wall. This tube is thicker than the guide wire and may also serve to enclose the sharp tip of guide wire 402 , to prevent inadvertent puncturing of nearby tissue. Alternatively, tube 404 may be an extension of punch tip 400 . Once tube 404 is advanced, guide wire 402 is optionally retracted.
[0138] In FIG. 20, punch tip 400 is advanced over tube 404 (or guide wire 402 or just advanced), to penetrate the aortic wall, so the aortic wall is received between punch base 406 and punch tip 400 .
[0139] In FIG. 21, punch base 406 is advanced through the aortic wall, to punch out the received section. Optionally, base 406 (and optionally punch tip 400 as well) are then further advanced As shown, punch base 406 optionally thickens as it is advanced, so that its final outer diameter is near the inner (and outer) diameter of catheter 100 and the hole in the aortic wall is widened. Alternatively, a balloon may be used. Such a thickening method may be used as an alternative in FIGS. 1 - 15 .
[0140] In FIG. 22, catheter 100 is advanced into the widened hole, as shown in FIG. 1, above.
[0141] A potential advantage of using a guide wire, is that if the needle punch is pushed to far ahead and then retracted out of the aorta wall, the guide wire can maintain the location of the hole formed by the punch, and prevent unnecessary damage of the aorta, caused by reinserting the punch at a second location.
[0142] [0142]FIGS. 23A and 23B illustrate an anti-dislodgment mechanism for a catheter 500 , in accordance with an exemplary embodiment of the invention. Catheter 500 comprises two layers, an inner layer 502 and an outer layer 504 . In an exemplary embodiment of the invention, the separation into two layers is only at the tip of the catheter, with the outer layer 504 transforming into one or more axial cords away from the tip.
[0143] Optionally, catheter 500 is provided through guide catheter 100 . In an exemplary embodiment of the invention, catheter 500 is conveyed through catheter 100 , until its tip passes the opening in the aorta. Catheter 100 may then be retracted, so that the aorta engages catheter 500 . Alternatively, catheter 500 maybe the only guiding catheter and replace catheter 100 .
[0144] In FIG. 23A Catheter 500 is shown extending out of an aorta 102 . However, in other uses, catheter 102 may be extending into a hollow body lumen, for example a blood vessel, a bladder or a digestive organ.
[0145] In FIG. 23B, inner layer 502 is retracted, while outer layer 504 is not, causing outer layer 505 to collapse, optionally about one or more pre-provided hinges 506 , so that the outer diameter of the collapsed portion is significantly greater than the diameter of the opening. Optionally, a plurality of slots is formed in outer layer 504 , to support such collapsing. Alternatively or additionally, to collapsing outside of aorta 102 , the collapsing may take place within the aortic wall, albeit not with a same diameter increase.
[0146] A suitable positioning of hinges and slots (axially separated by a collar of unslotted material) will allow outer layer 504 to form to portions of increased diameter, one inside the aorta and one outside. Alternatively, only a collapsed portion external to the aorta is formed, for example by providing a collar of unslotted material at the tip of catheter 500 .
[0147] Optionally a balloon 508 is temporarily inflated to assist and/or guide the collapsing, by actively widening the diameter of catheter 500 .
[0148] Optionally, a thin membrane or balloon is provided over the tip of catheter 500 , as part of the catheter, to prevent the slotted parts of outer layer 504 from inadvertently engaging any nearby tissue.
[0149] [0149]FIG. 24A illustrates a rotating and cutting out punch mechanism, in accordance with an exemplary embodiment of the invention. The mechanism is provided, for example, in catheter 500 and is used for cutting-out a section from an aorta 102 .
[0150] In an exemplary embodiment of the invention, the mechanism comprises an inner pivot section 600 that is inserted into the aorta wall, anchoring in the wall or transfixing the wall. Optionally, pivot section 600 has a sharp tip 601 . Alternatively or additionally, a sharp guide wire 402 (described above) is used to penetrate aorta 102 . Optionally, tip 601 is barbed or inflatable or can be rotated to engage the aortic wall, for example using a threading (not shown). Thus, inadvertent retraction of tip 601 and/or motion of the punch, may be prevented. Optionally, as noted above, tip 601 may be replaced by a thin tube, which may be self flaring, for example as described below. An external cutting tube 602 has a sharp edge 604 . Edge 604 may be smooth. Alternatively, it may be serrated, saw-tipped and/or may have a non-uniform diameter.
[0151] A plurality of threading sections 608 and 610 may couple tube 602 and pivot section 600 . Alternatively, other methods may be used. In an exemplary embodiment of the invention, there is a significant empty space between tip 601 and edge 604 . Tip 601 may be axially movable relative to edge 604 , however, they may have a fixed relative position, for example tip 601 recessed or advanced relative to edge 604 . In an exemplary embodiment of the invention, edge 604 advances towards tip 601 , as it rotates. Such rotation may be used for various types of rotating punches, includes punches with a single cutting spike axially extending from edge 604
[0152] In use, tip 601 is inserted into aorta 102 and tube 602 is rotated around it. An outer tube is optionally advanced into the hole thus formed Tip 601 and/or tube 602 are then retracted.
[0153] FIGS. 24 B- 24 D show an exemplary rotating punch 620 , in accordance with an exemplary embodiment of the invention. Punch 620 comprises a head 622 (one exemplary embodiment of which is described in general in FIG. 24A), an elongate shaft 624 , adapted for passing through a catheter or an endoscope, a handle 626 and a rotatable cam 628 . In an exemplary embodiment of the invention, cam 628 is coupled to tube 602 . Optionally, tip 601 is attached to an external grip 630 for selectively advancing and/or retracting tip 601 .
[0154] [0154]FIG. 24C is a close-up of head 622 , showing an optional (non-rotating or freely rotating) outer sheath 633 , having a narrowing cone 634 terminating at a lip 632 . In an exemplary embodiment of the invention, cone 634 is used to advance sheath 633 into an opening created by cutting edge 604 . Optionally, tube 602 and/or cone 632 are retracted, allowing the use of sheath 633 as a delivery guide. Alternatively, cone 634 is used to widen the punched hole, to assist in advancing the outer sheath (e.g., catheter or endoscope) into the punched hole.
[0155] [0155]FIG. 24D is a cross-sectional view of handle 626 , showing a hollow inner shaft 636 through which a retractable tip 630 is advanced.
[0156] FIGS. 24 E- 24 F show an alternative rotating punch 640 , in accordance with an exemplary embodiment of the invention. A rotating cam 648 is set on a side of a body 646 of punch 640 . A head 642 can be the same head 622 of FIG. 24B.
[0157] [0157]FIG. 24F is a view of the working mechanism of punch 640 , showing the rotation of a shaft 656 , while allowing an inner guide wire 650 to remain stationary and/or be moved axially. An optional safety pin 658 is also shown, for preventing inadvertent rotation of shaft 656 .
[0158] [0158]FIG. 25 illustrates a device delivery guide 700 , as an alternative to the capsule shown in FIG. 16, in accordance with an exemplary embodiments of the invention. In guide 700 , the tips of backward spikes 132 of connector 124 are engaged in a plurality of holes 704 , in a tubular element 700 .
[0159] [0159]FIG. 26 is an exploded view of the guide 700 , showing that a plurality of wings 702 is formed at the end of guide 700 , such that when they flare out, holes 704 release the tips of spikes 132 .
[0160] FIGS. 27 A- 27 C illustrate two exemplary anastomosis connectors, in accordance with an exemplary embodiment of the invention. FIG. 27A shows a connector 800 , in plan view having a body 802 comprised of a plurality of arcs 804 that interconnect adjacent spikes segments 806 . Spike segments 806 extend in one direction (the backwards direction), away from body 802 , to form a plurality of spikes 808 . In the opposite direction, spike segments 806 extend to form bases for a plurality of non-penetrating spikes 810 . In an exemplary embodiment of the invention, each of spike segments 806 splits into two bases 812 , however, this is not required. In an exemplary embodiment of the invention, spikes 810 are formed of two arms 814 that meet at a spike tip 815 and are attached at their other ends to spike bases 812 , of adjacent spike segments 806 . In an exemplary embodiment of the invention, arms 814 and bases 812 define an undulating curve. The exemplary dimensions shown are in mm.
[0161] [0161]FIG. 27B shows an alternative, embodiment, in which the form of the curve is different. Possibly, the form of FIG. 27A allows greater force to be applied by the twisted joints. Alternatively, the joints may be replaced by straight torsion bars. Optionally, the torsion bars are made thinner or weaker than the surrounding connector, to ensure that they twist. Optionally, the form of the curve is adapted to match a bending pattern of the undulating curve, as shown in FIG. 27C.
[0162] [0162]FIG. 27C shows a side cross-sectional view of a single spike segment 806 of connector 800 , showing an exemplary bend configuration of the spikes. Optionally, the sharp bends are achieved by twisting the spikes. In an exemplary embodiment of the invention, the spikes are pre-bent and connector 800 is elastic, super-elastic or shape memory, so that it attempts to return to the geometry shown in FIG. 27C, when delivered. Alternatively, connector 800 is a plastically deformed connector.
[0163] As shown, in an exemplary embodiment of the invention, spike 808 is a penetrating spike that is bent twice 90°. In an exemplary embodiment of the invention, the bending is performed by twisting of the spike, e.g., arms 814 or bases 812 . Spike 810 is a non-penetrating spike mounted on bases 812 (one shown). Base 812 is curved or bent away from segment 806 . Then, base 812 bends (or is twisted) at the point of attachment to arm 814 . Arm 814 is optionally curved so that tip 815 when contacting a vessel wall will tend to bend away from the wall, rather than attempt to penetrate it.
[0164] FIGS. 28 A- 28 B illustrate a method of mounting a connector, such as connector 800 , into a delivery system 900 , in accordance with an exemplary embodiment of the invention. FIG. 28A shows connector 800 mounted in a loading tube 902 . A graft 904 is everted over connector 800 and transfixed by spikes 808 . Spikes 810 are held between the graft and loading tube 902 .
[0165] A thin, flexible tube 906 is mounted on each spike 808 and passed through a slot 910 of an inner window tube 908 of delivery system 900 . An intermediate, locking tube 912 is optionally provided between window tube 908 and an outer tube 914 .
[0166] [0166]FIG. 28B shows the effect of pulling back on all the flexible tubes 906 substantially simultaneously. Graft 904 is pulled out of loading tube 902 . Spikes 810 (released from tube 902 ) are optionally allowed to open and engage the outer lip of tube 914 . Spikes 808 are pulled into slots 810 . In an exemplary embodiment of the invention, locking tube 912 is advanced, locking connector 800 between locking tube 912 and window tube 908 . Further retraction of tubes 906 will thus only cause the removal of tubes 906 from spikes 808 and not further retraction of connector 800 . Connector 800 is then optionally released, by retracting locking tube 912 .
[0167] It should be noted that locking connector 800 and/or the use of holding slot 910 potentially allow connector 800 to be selectively pulled or pushed within outer tube 914 .
[0168] FIGS. 29 A- 29 D show a method of mounting connector 800 , in accordance with an alternative exemplary embodiment of the invention. A graft loader 930 restrains a connector 800 , which transfixes an everted graft 902 . Unlike holder 902 of FIG. 28A, holder 930 includes one or more pins 932 , for folding pikes 808 back into a delivery system 940 (FIG. 29B). In an exemplary embodiment of the invention, holder 930 includes a ring 931 defining a plurality of through channels for a plurality of pins 932 , one for each spike 808 . Alternatively, a single pin is used for all spikes, in series.
[0169] In FIG. 29B, a forward tip 934 of pin 932 advances and bends spike 808 back. In an exemplary embodiment of the invention, delivery system 940 comprises outer tube 914 and an inner tube 942 , having an extending inner lip 944 . Tip 934 pushes spike 808 against inner lip 944 . A plurality of spike holders 946 , having inwards extending fingers 948 are provided to engage the tip of spikes 808 . Optionally, spikes holders 946 comprise sections of a single slotted tube. As shown, fingers 948 are proximal to the end of tube 942 , for example, by advancing tube 942 further than spike holders 946 , out of outer tube 914 .
[0170] In FIG. 29C, holders 946 are advanced, so that the tip of spike 808 is held between finger 948 , inner lip 944 and the front lip of tube 942 . Both holders 946 and tube 942 are optionally retracted, so that pulling hard on connector 800 will not inadvertently dislodge spikes 808 .
[0171] In FIG. 29D, delivery system 940 is retracted relative to graft holder 930 , so that connector 800 and graft 902 are pulled off of holder 930 . Optionally, spikes 810 open and engage tube 914 .
[0172] In an exemplary embodiment of the invention, the graft holder uses a graft conveying element in the shape of a flexible element with a retractable pin at its end. Such an element is described, for example in PCT/IL01/00069, the disclosure of which is incorporated herein by reference.
[0173] FIGS. 30 A- 30 C show details of the process of attaching connector 800 to an aorta 952 , in accordance with an exemplary embodiment of the invention, which does not necessarily require a capsule. In FIG. 30A, a hole has been punched in aorta 952 and a guide sheath 950 inserted in the hole, optionally plugging it. A delivery system including outer tube 914 and a graft 902 is advanced through sheath 950 and past the wall of aorta 952 , optionally along a guide wire 954 .
[0174] In FIG. 30B, guide sheath 950 is retracted out of the opening in the aorta, so that the wall of aorta 952 engages outer tube 914 instead. In addition, outer tube 914 is retracted sufficiently to allow non-penetrating spikes 810 to contact aorta 952 . In other embodiments, penetrating spikes are used. One potential advantage of non-penetrating spikes is that there is less danger of inadvertently damaging tissue or catching on tissue outside the aorta by the spikes.
[0175] Connector 800 is unlocked (in this implementation) by retracting first locking tube 912 and then window tube 908 . The extended spikes 810 prevent retraction of connector 800 .
[0176] In FIG. 30C, outer tube 914 is retracted, freeing spikes 808 to bend and engage aorta 952 opposite spikes 808 , completing the anastomotic connection of graft 902 to aorta 952 .
[0177] In an exemplary embodiment of the invention, the above or other methods of performing a bypass are used to connect a venous system to an arterial system, such that the venous system serves as a conduit for oxygenated blood.
[0178] In an exemplary embodiment of the invention, a graft is connected between the aorta, a mammary artery or other artery to the coronary sinus and/or to one or more of the coronary veins.
[0179] In an embodiment where the connection is to the coronary sinus, the connection between the coronary sinus and the vena cava is sealed, for example, using a suture, an internal suture, a clogging device or any other means of sealing blood vessels known in the art. Optionally, at least one of the coronary veins is disconnected from the coronary sinus and connected to the venous system, to provide some measure of venous drainage.
[0180] In an embodiment where the connection from the aorta is to a coronary vein, the connection of the vein to the coronary sinus is severed.
[0181] The access for performing the bypass procedures may be of any type known in the art, for example, transvascular, thoracic or using open surgery.
[0182] It will be appreciated that the above described methods of providing a tools and bypassing may be varied in many ways, including, changing the order of acts, which acts are performed more often and which less often, the arrangement of the tools, the type and order of tools used and/or the particular timing sequences used. Further, the location of various elements may be switched, without exceeding the sprit of the disclosure. In addition, a multiplicity of various features, both of methods and of devices have been described. It should be appreciated that different features may be combined in different ways. In particular, not all the features shown above in a particular embodiment are necessary in every similar exemplary embodiment of the invention. Further, combinations of features from different embodiments into a single embodiment or a single feature are also considered to be within the scope of some exemplary embodiments of the invention. In addition, some of the features of the invention described herein may be adapted for use with prior art devices, in accordance with other exemplary embodiments of the invention. The particular geometric forms and measurements used to illustrate the invention should not be considered limiting the invention in its broadest aspect to only those forms. Although some limitations are described only as method or apparatus limitations, the scope of the invention also includes apparatus designed to carry out the methods and methods of using the apparatus.
[0183] Also within the scope of the invention are surgical kits, for example, kits that include sets of delivery systems and anastomotic connectors. Optionally, such kits also include instructions for use. Measurements are provided to serve only as exemplary measurements for particular cases, the exact measurements applied will vary depending on the application. When used in the following claims, the terms “comprises”, “comprising”, “includes”, “including” or the like means “including but not limited to”.
[0184] It will be appreciated by a person skilled in the art that the present invention is not limited by what has thus far been described. Rather, the scope of the present invention is limited only by the following claims. | An anastomosis delivery system for delivering a connector having at least one backwards spike having a bent tip, comprising: a hollow guide sheath; and a hollow, axially slotted section, fitting within said sheath, said section having a flared configuration and an unflared configuration and wherein said axially slotted section is adapted to contain at least a part of said connector and to limit axial motion of said connector when said section is in its unflared configuration. | 0 |
RELATED APPLICATIONS
This application claims priority to U.S. Provisional Application, entitled “Apparatus and Method for a Baggage Check and Promotional Advertisement,” filed Feb. 6, 2007, Ser. No. 60/899,775, and to U.S. Provisional Application, entitled “Apparatus and Method for Baggage Check and Promotional Advertisement,” filed Nov. 2, 2007, Ser. No. 61/001,776.
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a luggage identification tag and system for promotional advertising for use by hotels, casinos and the like.
BACKGROUND OF THE INVENTION
Hotels, casinos and the like go to various efforts to promote shows or restaurants or other forms of entertainment owned, produced or operated by the hotels or casinos or in partnership with other hotels or casinos or related organizations. Oftentimes, substantial amounts of money are expended toward these efforts with the ultimate goal being to coax or encourage consumers to a particular destination either within or nearby the hotel or casino. The present invention provides a means to accomplish this objective simply and inexpensively.
SUMMARY OF THE INVENTION
A luggage tag and method for promotional advertisement is disclosed. The luggage tag includes a substrate having first and second sides, and information printed thereon for identification of luggage and promotional advertisement.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 depicts a first side of an embodiment of a luggage tag system of the present invention, having luggage ownership identifying information or space therefore and scratch-surface panels for promotional advertising;
FIG. 2 depicts a second side of an embodiment of a luggage tag system of the present invention having further luggage ownership identifying information printed thereon;
FIG. 3 depicts a first side of a further embodiment of a luggage tag system of the present invention having a scratch surface;
FIG. 4 depicts a second side of the embodiment disclosed in FIG. 3 having a portion for providing luggage ownership information thereon;
FIG. 5 depicts a cross sectional view of the two layer flexible vinyl substrate used in making the embodiment of the present invention illustrated in FIGS. 3 and 4 ;
FIG. 6 depicts a further cross sectional view of the two layer flexible vinyl substrate used in making the embodiment of the present invention illustrated in FIGS. 3 and 4 with the inclusion of kiss-cuts and scratch layer;
FIG. 7 depicts a cross sectional view of an apparatus for preparing one embodiment of the luggage tags of the present invention from pre-prepared stock; and
FIG. 8 depicts a perspective view of the embodiment disclosed in FIGS. 3 and 4 shown attached to a luggage case.
DETAILED DESCRIPTION OF THE INVENTION
This invention concerns apparatus and methods for use by hotels, casinos and the like to identify ownership of luggage and to provide promotional advertisement. Referring, for example, to FIGS. 1 and 2 , a luggage tag 10 of the present invention is illustrated. The luggage tag 10 includes a generally flat substrate 12 having a first surface 20 and a second surface 30 . Generally speaking, the first surface 20 comprises a front side of the flat substrate 12 while the second surface 30 comprises a back or opposite side of the flat substrate 12 . The flat substrate 12 of the luggage tag 10 can be constructed using any suitable material, such as, for example, plastic, paper, vinyl or cardboard, or a combination thereof.
Referring particularly to FIG. 1 , the first surface 20 includes a first portion 22 for printing ownership identifying information. The ownership identifying information includes generally the owner's name, the number of pieces of luggage and any additional information that is helpful in tracking or delivering the luggage—e.g., the room number of the owner while a guest at a hotel or casino. An identification serial number 23 and, if desired, a corresponding variable barcode 24 , is printed on the luggage tag for further identifying purposes.
The first surface 20 further includes a second portion 26 that is removably connected to the first portion 22 through a perforated segment 27 allowing the first section 22 and second section 26 to be separated. A first scratch surface 40 is provided on the first portion 22 and a second scratch surface 42 is provided on the second portion 26 . The first 40 and second 42 scratch surfaces cover printed information concerning a promotional advertisement, and serve to keep the information hidden prior to the scratch surfaces being scratched away by a user's fingernail or coin or the like. Referring to FIG. 2 , the second surface 30 includes one or more identifying labels 32 . The identifying labels 32 are preferably kiss-cut and removably attached to the second surface 30 .
In one embodiment, a method for identifying ownership of luggage and providing a promotional advertisement is disclosed. Specifically, upon arrival by a guest at a hotel or casino, a luggage tag 10 of the present invention is obtained by a hotel or casino employee. Information concerning the name of the guest and the number of pieces of luggage is noted on the first portion 22 of the luggage tag 10 , along with the room number or cell phone number or other pertinent identifying information. Luggage identifying labels 32 are then detached from the second surface 30 of the luggage tag 10 and removeably attached to the individual pieces of luggage, which are thereafter transported to the guest's room by a bellhop or other hotel or casino employee. The second portion 26 of the luggage tag is then separated from the first portion 22 by tearing along the perforated segment 27 . The second portion 26 is provided to the guest and the first portion 22 is provided to the bellhop.
Following arrival and check-in of luggage, the guest may proceed to his or her room or where they might otherwise desire. At the same time or thereafter, the luggage is transported to the guest's room and the first portion 22 of the luggage tag 10 is left with the delivered luggage or at a suitable location where the guest may locate the first portion 22 . The guest may then scratch away the first 40 and second 42 scratch-surface portions, thereby revealing or exposing first 50 and second 52 printed promotional materials previously blocked from view by the scratch-surfaces. In an embodiment, if both the first 50 and second 52 printed promotional materials match, then the guest wins whatever is being advertised by the first 50 and second 52 printed promotional material—e.g., a ticket or tickets to a show or dinner at a restaurant.
Referring now to FIGS. 3 and 4 , a further embodiment of the present invention is disclosed. Specifically, a luggage tag 50 includes a substrate 53 having a first surface 52 and a second surface 54 . Generally speaking, the first surface 52 comprises a front side of the substrate 53 while the second surface 54 comprises a back or opposite side of the substrate 53 . The substrate 53 of the luggage tag 50 can be constructed using any suitable material, such as, for example, plastic, paper, vinyl or cardboard, or a combination thereof.
Referring particularly to FIG. 3 , the first surface 52 includes a first portion 56 and a second portion 60 . The first portion 56 and the second portion 60 are separable by a perforated segment 62 . The first portion 56 of the first surface 52 includes space for one or more identifying labels 58 . Each identifying label 58 preferably includes a unique identifying serial number 57 (e.g., “10007” as illustrated) and, if desired, a corresponding barcode (not illustrated) for identifying purposes. Alternatively, each identifying label may include simply a bar code. The identifying labels 58 are preferably kiss-cut and removably attached to the first surface 52 . The unique identifying serial number 57 is, preferably, also printed elsewhere on the first surface 52 at a location—e.g., location “ 61 ”—where it does not interfere with the identifying labels 58 . The first portion 56 also includes space for a scratch surface 64 . The scratch surface 64 covers information printed underneath thereof on the first surface 56 concerning a promotional advertisement or solicitation, and serves to keep the information hidden prior to the scratch surface being scratched away by a user's fingernail or coin or the like.
Referring to FIG. 4 , the second surface 54 includes a first portion 66 and a second portion 67 . The first portion 66 and the second portion 67 are separable by a perforated segment, preferably the same perforated segment 62 referred to above. The first portion 66 of the second surface 54 includes space for printing various identifying information including, for example, ownership identifying information 80 . The ownership identifying information 80 includes generally the owner's name, the number of pieces of luggage and any additional information that is helpful in tracking or delivering the luggage—e.g., the room number of the owner while a guest at a hotel or casino. The ownership identifying information 80 is printed at a suitable location—e.g., location “ 69 ”—on the first portion 66 of the second surface 54 . The first portion 66 of the second surface 54 further includes space for printing additional information—e.g., a disclaimer—relating to the promotional advertisement appearing under the scratch surface 64 located on the second portion 60 of the first surface 52 of the luggage tag 50 . The same additional information may, if desired, be printed on the second portion 67 of the second surface 54 . The unique identifying serial number 57 and, if desired, a corresponding barcode 72 , is also be printed on the second portion 67 of the second surface 54 for further identifying purposes. Preferably, the first portion 66 and the second portion 67 of the second surface 54 are separable using the perforated segment 62 —i.e., the same perforated segment used to separate the first portion 56 and the second portion 60 of the first surface 52 .
Referring now to FIGS. 5 and 6 , further details of an embodiment similar to that just discussed are disclosed. Referring to FIG. 5 , for example, the flat substrate 53 is constructed from a substrate stock having, in cross section, a first layer 91 and a second layer 92 . The first layer 91 includes a vinyl sheet having an adhesive underside 94 and a topside 95 suitable for lithographic printing. The second layer 92 includes a vinyl sheet having an adhesive receiving underside 96 and a topside 97 suitable for lithographic printing. Referring also to FIGS. 3 and 4 , the first surface 52 of the flat substrate 53 corresponds to the topside 95 of the first layer 91 and the second surface 54 of the flat substrate 53 corresponds to the topside 97 of the second layer 92 . A suitable dual-layer flexible vinyl substrate as described herein and above may be purchased from Fasson®. The substrate may be purchased on either rolls or sheets suitable for use with lithographic processing techniques.
Referring now to FIGS. 5 and 6 and to FIGS. 3 and 4 where appropriate, the first layer 91 includes the first portion 56 and the second portion 60 of the first surface 52 . The topside 95 of the first layer 91 includes a suitable space at the first portion 56 —e.g., location “ 61 ”—for printing the unique identifying serial number 57 (e.g., “10007” as illustrated). The first layer 91 further includes one or more identifying labels 58 . The identifying labels 58 each include the unique identifying serial number 57 or bar code (not illustrated) printed on the topside 95 . The identifying labels 58 are preferably sectioned by kiss-cuts 90 extending through the first layer 91 and removably attached to the second layer 92 by the adhesive underside 94 of the first layer 91 . The first portion 56 and the second portion 60 of the first layer 91 are separable through the perforation segment 62 . The scratch surface 64 is provided on the topside 95 of the first layer 91 at a suitable space at the second portion 60 . The unique identifying serial number 57 is, preferably, also printed on the on the topside 95 of the first layer 91 at the second portion 60 in an area not obscured by the scratch surface 64 . In one embodiment, the scratch surface 64 comprises a grey ultraviolet layer that may be applied using standard techniques know to those having skill in the art. In a further embodiment, the scratch surface 64 comprises a grey ultraviolet layer 64 A applied on top of a previously applied clear ultraviolet layer 64 B. The clear ultraviolet layer 64 B serves to protect the promotional advertisement, solicitation or other printed information from being scratched away during the process of removing the scratch surface 64 by a user's fingernail or coin or the like.
Referring still to FIGS. 3-6 , the second layer 92 includes the first portion 66 and the second portion 67 of the second surface 54 . The topside 97 of the second layer 92 includes a suitable space at the first portion 66 —e.g., location “ 69 ”—for printing the ownership identifying information 80 and the disclaimer relating to the promotional advertisement appearing under the scratch surface 64 . The first portion 66 and the second portion 67 of the second layer 92 are separable through the perforation segment 62 . The topside 97 of the second layer 92 at the second portion 67 includes space for printing additional information—e.g., the disclaimer referred to above—and, in addition, the unique identifying serial number 57 . If desired, a barcode 72 corresponding to the unique identifying serial number 57 is also printed on the topside 97 of the second layer 92 at the second portion 67 for identifying purposes. The second layer 92 further includes first 82 and second 83 removable portions that are defined and sectioned by first 84 , second 85 and third 86 kiss-cut segments extending through the layer. The first 82 and second 83 removable portions are removed from the second layer 92 thereby exposing corresponding portions of the adhesive underside 94 of the first layer 91 that can be secured to one another so as to form a loop securable about a luggage handle or the like.
Referring now to FIG. 7 , one embodiment of a process for applying the scratch surface 64 and performing the kiss-cutting and additional cutting operations to a substrate is disclosed. Specifically, a continuous feed of flexible vinyl substrate 200 similar to the two-layer substrate described above is fed to a processing apparatus 201 . The processing apparatus 201 comprises a clear ultraviolet coating applicator 202 , a grey ultraviolet coating applicator 204 , a kiss-cutting device 206 and a die cutting device 208 . In one embodiment, the flexible vinyl substrate 200 has previously undergone lithographic processing and has imprinted thereon a series of luggage tags having one or more of the various segments of printed information described above applied to the topside 95 of the first layer 91 and the topside 97 of the second layer 92 . The substrate 200 then passes through the clear ultraviolet coating applicator 202 where a clear ultraviolet coating 64 B is applied to a suitable space of the second portion 60 as described and illustrated above—see, e.g., FIGS. 3 and 6 . Following application of the clear ultraviolet layer 64 B, the substrate 200 then passes through the grey ultraviolet coating applicator 204 where a grey ultraviolet coating 64 A is applied to the suitable space of the second portion 60 as described and illustrated above. In an alternative embodiment, only one applicator is employed to apply only the grey ultraviolet coating.
Following application of the grey ultraviolet coating or both the clear and grey ultraviolet coatings, the substrate 200 then passes through the kiss-cutting device 206 , where both layers of the substrate 200 are kiss-cut in the positions indicated in, for example, FIG. 6 , including the perforated segment 62 . The kiss-cutting operation leaves the substrate 200 and the layers 91 , 92 comprising the substrate still intact. At this point, the kiss-cut substrate 207 passes through a die-cutting device 208 . The die-cutting device 208 is configured to cut through both layers 91 , 92 of the substrate 200 in a pattern that yields the final luggage tag 50 product, as illustrated, for example, in FIGS. 3 and 4 . As the substrate passes through the die-cutting apparatus 208 and is die-cut, the cut luggage tags 50 are collectably received in a manner known by those having skill in the art—e.g., in a stack 211 adjacent the die-cutting device 208 . The remainder of the substrate 200 is then passed to a collecting device—e.g., a roll (not illustrated)—where the remainder is collected for disposal.
Those having skill in the art will appreciate that the above described process may occur in “single row-series,” where a single row of luggage tags 50 is imprinted on the substrate 200 and processed with the ultraviolet layer(s), kiss-cut and then die-cut, or in “parallel row-series,” where parallel rows of luggage tags 50 are imprinted on the substrate 200 processed with the ultraviolet layer(s), kiss-cut and then die-cut.
In one embodiment of use, a method for identifying ownership of luggage and providing a promotional advertisement is disclosed. Referring, for example, to FIGS. 3 , 4 and 8 , upon arrival by a guest at a hotel or casino, a luggage tag 50 of the present invention is obtained by a hotel or casino employee. Information concerning the name of the guest and the number of pieces of luggage is noted on the second portion 67 of the second surface 54 of the luggage tag 50 , along with the room number or cell phone number or other pertinent identifying information of the guest or the identification number of the employee. The first 82 and second 83 removable portions are removed from the second layer 92 thereby exposing corresponding portions of the adhesive underside 94 of the first layer 91 . Referring now to FIG. 7 , the luggage tag 50 is then looped through a handle 101 or strap of a luggage piece 100 followed by the now exposed corresponding portions of the adhesive underside 94 being secured to one another, thereby forming a loop 102 preventing removal of the luggage tag 50 from the luggage piece 100 . Luggage identifying labels 58 are then detached from the first layer 91 of the luggage tag 50 and secured using the adhesive underside 94 to the handles or other suitable locations of any other individual pieces of luggage. Each piece of luggage is thus uniquely identified for transport to the guest's room by a bellhop or other hotel or casino employee.
Following the securing of the luggage tag 50 and labels 58 to the guest's luggage pieces, the luggage tag 50 is separated into a first tag portion 105 and a second tag portion 106 by tearing the perforation segment 62 that extends through both the first 91 and second 92 layers of the luggage tag 50 . The first tag portion 105 remains secured to the luggage piece 100 while the second tag portion 106 is handed to the owner of the luggage piece 100 . The owner may then, at his or her convenience, remove the scratch surface 64 , thereby revealing a prize—e.g., a ticket or tickets to a show or dinner at a restaurant—or other promotional item.
While certain embodiments and details have been included herein and in the attached invention disclosure for purposes of illustrating the invention, it will be apparent to those skilled in the art that various changes in the methods and apparatuses disclosed herein may be made without departing form the scope of the invention, which is defined in the appended claims. | An apparatus and method for identifying luggage and promotional advertising for use by hotels, casinos and the like are disclosed. The apparatus includes a tag having a first side having a scratch surface covering promotional material and a second side having a portion for printing identifying information. The tag and the promotional material can be used by a hotel, casino or the like to encourage guests to attend shows or dine at restaurants being promoted. | 6 |
FIELD OF THE INVENTION
The field of the present invention is that of an automotive vehicle door window regulator system for extendable windows, especially in hard-top or convertible vehicles.
BACKGROUND OF THE INVENTION
There are two major types of vehicle door window arrangements. The first arrangement is that of a sedan-type vehicle door. In the sedan-type vehicle door, the door has a channel that extends above the belt level of the door and encloses a glass window pane when the glass window pane is in its top position. A second type of vehicle door is the hard-top vehicle door wherein the glass, after extending from the belt line of the vehicle door, is totally unsupported above the belt line and mates with the weatherstrip along a door opening of the vehicle. In the hard-top design, the stability of the window glass is totally achieved by its connection with the door below the belt line of the vehicle door. The hard-top vehicle door is also used in convertibles and other vehicle body styles.
Many vehicle doors with extendable windows of the hard-top variety have two parallel channels mounted within the interior of the door. A cross arm (as in Lam et al, U.S. Pat. No. 4,924,627), a cable (as in Dupuy, U.S. Pat. No. 5,067,281) or a tape drive (as in Staran et al, U.S. Pat. No. 4,642,941) regulator mechanism is thereafter attached with the vehicle door. Thereafter, the glass window is attached to the channel members via guide blocks to complete the assembly. The various components are then adjusted to ensure the proper fit of the window and to prevent any possible binding in the up and down movement of the window.
To reduce costs, and in an attempt to prevent alignment problems, it is desirable to allow the channel members and regulator mechanism to be assembled into the vehicle door as one pre-assembled unit with the guide blocks already on the channel members.
In Bisnack et al, U.S. Ser. No. 08/412,813, filed Mar. 29, 1995, a modular window regulator system was presented which allowed virtually complete testing of the regulator system for possible binds before installation into the vehicle door. The window regulator of Bisnack et al greatly diminishes any possible binds due to its unique structure. However, the elimination of possible binds presents a problem with inboard and outboard stability. Inboard and outboard stability (or transverse stability) of the glass is mainly noticeable due to rattling of the window glass when the vehicle door is slammed shut. Previously, stability was added to the system due to the inherent binding which was part of the window regulator system. As mentioned previously, with the window regulator of Bisnack et al, a large amount of the binding is eliminated. Therefore, the binding effect due to slight misalignment of the various portions of the window regulator system may no longer be relied upon for transverse stability of the window glass regulator system.
SUMMARY OF THE INVENTION
The present invention provides a window regulator which has enhanced transverse stability while at the same time providing a minimum of binding for the extension and retraction of the window glass.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a window regulator which utilizes the present invention installed into a vehicle door.
FIG. 2 is a view similar to that of FIG. 1 with the door envelope removed, revealing the inboard side of the window regulator system shown in FIG. 1.
FIG. 3 is an enlarged view of a guide attached to the window glass and sash of the window regulator slidably mounted on a fore channel.
FIG. 4 is a view taken along line 4--4 of FIG. 3.
FIG. 5 is a view similar to that of FIG. 3 illustrating the guide slidably mounted on the aft channel.
FIG. 6 is a view taken along line 6--6 of FIG. 5.
FIG. 7 is an enlarged side elevational view of a button utilized as the transverse stabilizer in the preferred embodiment window regulator according to the present invention.
FIG. 8 is a view taken along line 8--8 of FIG. 7.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIGS. 1 through 8, a hard-top vehicle door 3 utilizing a window regulator system 7 is installed in a door body envelope 2 with an extendable and retractable glass, plastic or other rigid material window pane 4. The door body 2 has an outer panel 6 and an inner panel 8 spaced away from the outer panel 6. The inner panel 8 is capped by a top plate 9 which is joined by fasteners 11. The inner panel 8 and outer panel 6 form a spaced envelope or cavity having a top opening 10 (FIG. 2) and a major axis 13. The top opening 10 is covered by flexible elastomeric seals (not shown). The window 4 extends in and out of the door body 2 via the top opening 10 between the aforementioned seals.
The top edge 14 and side edges 16 and 18 of the glass window pane 4, as mentioned previously, are unsupported by the door 3 and rest against appropriate weatherstripping placed in the door opening (not shown) of a vehicle. Thus, the window regulator system 7 is that of a hard-top vehicle regulator used in hard tops or convertibles. Therefore, stability of the window 4 in the fore and aft direction of the vehicle, the vertical up and down direction of the vehicle, the transverse direction of the vehicle and in a rotational sense of the glass window pane 4 (movement in the plane of the window pane 4) must be achieved by window regulator system 7.
Pivotally joined to each other at point 20 are the first 22 and second 24 cross arm assemblies. The first cross arm assembly 22 has a first end 26 with gear teeth.
A backing plate 28 extends generally in a fore and aft direction with a first end 30 and a second end 32. The backing plate 28 mounts a driver gear 34 (shown in hidden line, FIG. 2, typically toward the outboard side of the backing plate) which is torsionally engaged with the geared tooth end 26 of the first cross arm 22. The drive gear 34 is driven by an electric motor 36 in response to an operator command to translate the window pane 4 in (down) and out (up) of the vehicle door body 2. The backing plate also supports the electric motor 36. Additionally, the backing plate 28 has a linear slot 38 which mounts a polymeric slider 40 which is pivotally connected to the first end 42 of the second cross arm 24.
Fixably connected to the first end 30 of the backing plate is a first channel 44. The first channel 44 extends generally transverse to the backing plate and is oriented generally vertically although slightly inclined. Additionally, the first channel 44 is slightly concave, sloping in an inboard direction as it vertically extends upward, nearly matching the curvature of the window glass 4. Referring additionally to FIGS. 3, 4 and 5, the first channel 44 has a fore and aft flat or blade 46 joined to sides 48 and 50 and a final transverse member or blade 52. The blade 46 is generally parallel to the major axis 13.
The window regulator system 7 also has a sash 54 which is formed by a channel 56 which is typically weldably connected at a first fore end 58 and a second aft end 60. In an alternative embodiment (not shown), the connection may be by bolts or other fasteners. The sash channel 56 via sliders 62 slidably mounts second ends 64, 66 of the first and second cross arms 22, 24, respectively.
Referring to FIGS. 3-6, fixably joined to the window glass 4 and to the first end 58 of the sash 54 by a fastener 68 is a first guide block 70. In the presently shown embodiment, the guide block 70 is directly connected to the window glass 4, but in other embodiments (not shown), the window glass may be fixed to the sash and the sash may be directly connected to the guide block. The guide block 70 is primarily fabricated from a metallic member 72 which is generally integral with the end 58 of the sash 54. The metallic member 72 is encapsulated with a polymeric material 74 which may be nylon, a glass fiber filled nylon or other suitable material such as acetal. The guide block 70 has a lower transverse alignment beating 76 and an upper transverse alignment beating 78. Bearings 76 and 78 have generally noncompliant inner lobes 80 and outer lobes 82 which impinge on blade 46 of the channel to provide a vertical bearing which aligns and confines the travel of the glass in the inboard and outboard (transverse) directions.
Referring to FIGS. 6 and 7, connected to the backing plate 28 in a similar fashion to that of the first channel 44 is a rear channel 86. The rear channel 86 has blade 46 and members 52, 50 and 48 in similar fashion to that of the first channel 44. Integrally joined to the second end 60 of the sash 54 and slidably mounted on blade 46 by lower and upper bearings 76 and 78 is a second guide block 90. In a like manner, guide block 90 is connected by welding or a mechanical method similar to fastener 68 to the second end 60 of the sash of glass pane 4. Referring in more detail to FIG. 7, the second guide block 90 has a fore and aft beating 92 having fore lobe 94 and aft lobe 96 which provide a fore and aft bearing upon blade 52. The fore and aft being 92 sets the fore and aft position of the window glass 4 as the window glass is extended or retracted by the window regulator system 7.
The elevation of bearing 92 should be different than that of the second ends 66 and 64 of the cross arms so that a moment force in the plane of the glass 4 sets up a three-point force resistance between bearing 92 and ends 66 and 64 of the cross arms. Referring back to FIGS. 3 and 4, blade 52 of the first channel 44 has a clearance to ensure that there is only three-point and not four-point support of the window against moment forces, thereby reducing problems of binding which would be inherent with four-point resistance since in order for four-point resistance to work, the tolerance between the parallelism of the blades 52 would have to be far smaller to ensure the elimination of binding forces.
Optionally, the first channel has a glass stabilizer 100 to stabilize the glass for door slam (transverse glass motion) and at its bottom end has a blade 102. Blade 102 is utilized in the installation of the window regulator 7 to the door 3 in a manner described in Wirsing, U.S. Pat. No. 5,430,976 filed Jul. 11, 1995. The rear channel 86 also has fixably attached thereto a bracket 104 which attaches the aft end of the window regulator system 7 to the inner panel 8 if needed in an adjustable fashion. A top plate 9 becomes part of the door body and also fixably connects the top ends of the channels 44 and 86 to one another. An advantage of the window regulator system 7 is that it can be installed as a single unit with the window glass on or off. Additionally, the window regulator system 7 can be tested for any possible binding before installation into the vehicle door 3, as compared to the prior system which required testing after installation since the separate pieces were assembled as separate members into the vehicle door inner panel.
Since the front side edge 16 of the window glass is at an angle, fore and aft adjustment of the regulator system 7 to match the vehicle door opening is critical. The whole regulator system 7 may be adjusted fore and aft due to movement of the blade 102 in the holding fixture 130 as described in aforementioned Wirsing U.S. Pat. No. 5,430,976 and due to slots 132 provided in the top plate 9. The fasteners which connect with bracket 104 are inserted into slots (not shown) of the inner panel 8 to allow for fore and aft adjustment.
Inboard and outboard alignment of the window pane 4 is determined by the juxtaposition of the blade 46 between the inner lobe 80 and the outer lobe 82 of the bearings 76 and 78. A small amount of clearance (approximately 0.20 mm) between the blade 46 and the inner and outer is desirable in order to prevent any binding, however, this clearance provides room for rattling upon door closure. To prevent any possible rattling, there is a spring button 170 to take up the clearance. Spring button 170 has a generally conical shape with an apex 172 and a main body and a stem 174. A base 176 of the button rests on a surface 180 of the guide block 70. The button stem 174 is compliantly held within a hole 182 which is drilled or molded into the guide block 70. The entrapment of the button by the blade 46 prevents the spring button 170 from falling out. The entrapment of the spring button 170 also compliantly loads the spring button 170 to exert a spring force on the blade 46 to take up any slack between the beating lobes 82 and 80, thereby preventing the rattling which may occur during the closing operation of the door and taking out any lateral or inboard and outboard compliance.
A conical portion 184 of the button has four geometrically spaced triangular shaped cutouts 186 with curved ends to provide for stress relief of the button to prevent stress fractures, thereby enhancing the life of spring button 170. The spring button 170 will typically be made from an acetal plastic material. Referring to FIG. 3, two spring buttons 170 will often be utilized, and the spring buttons 170 will be placed to straddle bearings 76 and 78. In like manner, the spring buttons 170 will be utilized for the rear guide block 90. Since their operation is essentially identical, the explanation will be omitted in the interest of brevity.
Due to its conical shape, the spring button 170 will have a variable spring rate which will increase upon displacement of the blade 46 toward the lobe 80. Therefore, the normal force that the spring button 170 exerts against the blade will only be maximized when needed and will be at a minimum during normal window regulator operation. Also, since the spring button 170 is a plastic material with a low coefficient of friction, very little friction is induced between the spring button 170 and the blade.
While this invention has been described in terms of a preferred embodiment thereof, it will be appreciated that other forms could readily be adapted by one skilled in the art. Accordingly, the scope of this invention is to be considered limited only by the following claims. | A window regulator system is provided for translating a window. The regulator includes at least one channel extending vertically in the door cavity for guiding the window; a blade connected to the channel and extending parallel to the major axis of the door cavity; a guide block fixed to the window and having a transverse alignment bearing with two generally noncompliant bearing lobes juxtaposed by the blade for aligning the window in a direction transverse to the major axis of the door cavity; and a spring button connected to the guide block and being of a generally hard polymeric material having a generally conical shape with an apex contacting the blade and a base compressed against the guide block for removing transverse compliance of the window within the alignment bearing. | 4 |
FIELD OF THE INVENTION
[0001] The present invention relates to a reinforcement for insertion into a sash of an operator window formed of plastic hollow members to which a latch or lock mechanism can be secured.
BACKGROUND
[0002] Various types of operator windows are known in which a sash is movable relative to a perimeter frame between respective open and closed positions of the window. Locking or latching the window closed typically requires a plurality of connectors to be mounted along mating edges of the sash and the perimeter frame for engagement with one another. When securing a connector, for example a lock keeper, to a sash formed of hollow plastic members, fasteners are known to come loose from the sash over time. A reinforcement member can be mounted in the hollow plastic member forming the sash to span between an adjacent pair of lock keepers, however in regions where climate fluctuates considerably between different seasonal temperatures, the different rates of expansion and contraction of the reinforcement member and the plastic of the sash can cause the sash to bow and not fit properly within the perimeter frame.
SUMMARY OF THE INVENTION
[0003] According to one aspect of the invention there is provided in an operator window comprising:
[0004] a perimeter frame arranged to be mounted about a perimeter of a window opening, the perimeter frame including a latching side;
[0005] a sash supported on the perimeter frame and arranged to be movable relative to the perimeter frame between opened position and closed positions of the window, the sash including a latching side arranged to engage the latching side of the perimeter frame in the closed position of the window, the latching side comprising an elongate hollow member; and
[0006] a latching mechanism including a plurality of first mating connectors supported at spaced positions along the latching side of the perimeter frame and a plurality of second mating connectors supported at spaced positions along the latching side of the sash, the second mating connectors being arranged to mate with respective ones of the first mating connectors so as to latch the sash in relation to the perimeter frame in the closed position of the window;
[0007] an improvement comprising a plurality of reinforcement members received through the elongate hollow member forming the latching side of the sash at spaced positions along the elongate hollow member, each reinforcement member being fastened to a respective one of the second mating connectors such that said reinforcement member is spaced apart from the other reinforcement members.
[0008] According to a second aspect of the present invention there is provided a method of reinforcing a sash in an operator window comprising:
[0009] a perimeter frame arranged to be mounted about a perimeter of a window opening, the perimeter frame including a latching side;
[0010] a sash supported on the perimeter frame and arranged to be movable relative to the perimeter frame between opened position and closed positions of the window, the sash including a latching side arranged to engage the latching side of the perimeter frame in the closed position of the window, the latching side comprising an elongate hollow member;
[0011] a latching mechanism including a plurality of first mating connectors supported at spaced positions along the latching side of the perimeter frame and a plurality of second mating connectors supported at spaced positions along the latching side of the sash, the second mating connectors being arranged to mate with respective ones of the first mating connectors so as to latch the sash in relation to the perimeter frame in the closed position of the window;
[0012] the method comprising:
[0013] inserting a plurality of reinforcement members through the elongate hollow member forming the latching side of the sash;
[0014] positioning the reinforcement members spaced apart from one another; and
[0015] fastening each reinforcement member to a respective one of the second mating connectors.
[0016] According to a further aspect of the present invention there is provided an operator window comprising:
[0017] a perimeter frame arranged to be mounted about a perimeter of a window opening, the perimeter frame including a latching side;
[0018] a sash supported on the perimeter frame and arranged to be movable relative to the perimeter frame between opened position and closed positions of the window, the sash including a latching side arranged to engage the latching side of the perimeter frame in the closed position of the window, the latching side comprising an elongate hollow member;
[0019] a latching mechanism including a plurality of first mating connectors supported at spaced positions along the latching side of the perimeter frame and a plurality of second mating connectors supported at spaced positions along the latching side of the sash, the second mating connectors being arranged to mate with respective ones of the first mating connectors so as to latch the sash in relation to the perimeter frame in the closed position of the window; and
[0020] a plurality of reinforcement members received through the elongate hollow member forming the latching side of the sash at spaced positions along the elongate hollow member, each reinforcement member being fastened to a respective one of the second mating connectors such that said reinforcement member is spaced apart from the other reinforcement members.
[0021] By providing a plurality of independent reinforcement members which are mounted spaced apart from one another within the latching side of a sash, mating connectors of a latching mechanism can be secured to the reinforcement members within the sash without concern for different rates of expansion and contraction between the different materials of the reinforcement members and sash as the space between the reinforcement members accommodates for different amounts of expansion and contraction without forcing the sash to bow.
[0022] There may be provided a spacer mounted between each adjacent pair of reinforcement members to maintain the spacing therebetween during installation with the spacers being small enough that the reinforcement members may be installed with a gap between each spacer and the adjacent reinforcement members.
[0023] Preferably the spacer substantially fully spans a cross section of a hollow channel receiving the reinforcement members in the elongate hollow member forming the latching side of the sash.
[0024] The spacer may be formed of a plastic material which is softer than both the material forming the reinforcement members and the material of the elongate hollow member forming the latching side of the sash.
[0025] The reinforcement members are preferably formed of metal with the elongate hollow member forming the latching side of the sash being formed of plastic material.
[0026] The method of installation of the reinforcement members may include positioning the latching side of the sash to span generally horizontally prior to fastening each reinforcement member to a respective one of the second mating connectors. The method may further include tilting the latching side of the sash to slope downwardly towards a first end and securing second mating connector to the reinforcement member nearest to the first end, and subsequently tilting the latching side of the sash to slope downwardly towards a second end and securing the second mating connector to the reinforcement member nearest to the second end.
[0027] When providing more than two second mating connectors, the method preferably includes fastening intermediate ones of the second mating connectors to the respective reinforcement members prior to fastening outermost ones of the second mating connectors to the respective reinforcement members.
[0028] One embodiment of the invention will now be described in conjunction with the accompanying drawings in which:
BRIEF DESCRIPTION OF THE DRAWINGS
[0029] FIG. 1 is a front elevational view of a latching side of both a perimeter frame and a sash of an operator window;
[0030] FIG. 2 is a side elevational view of a member forming the latching side of the sash; and
[0031] FIG. 3 is an end view of the member forming the latching side of the sash.
[0032] In the drawings like characters of reference indicate corresponding parts in the different figures.
DETAILED DESCRIPTION
[0033] Referring to the accompanying figures there is illustrated a reinforcement for a sash 10 of an operator window 12 . More particularly the reinforcement is arranged for reinforcing the attachment of a latching mechanism to an operator window formed of hollow plastic frame members.
[0034] The present invention is generally applicable to an operator window 12 of the type having a perimeter frame 14 arranged to be mounted about a perimeter of a window opening. A latching side 16 of the perimeter frame is shown formed of a hollow plastic frame member joined to similar hollow plastic frame members forming the top and bottom sides of the perimeter frame.
[0035] As in a conventional operator window, the sash 10 is mounted within the perimeter frame 14 for movement relative thereto between an open position in which the window opening surrounded by the perimeter frame is at least partially unobstructed and a closed position in which window panes fully span the window opening. The sash itself thus at least partially obstructs the window opening in the closed position. The sash also includes a latching side 18 formed of an elongate hollow plastic member, for example vinyl. The latching side 18 of the sash is opposite the hinged or otherwise mounted side of the sash which supports the sash on the perimeter frame 14 . The latching sides 16 and 18 of the perimeter frame and sash respectively engage one another in the closed position of the window.
[0036] A latching mechanism is provided for latching or locking the sash relative to the perimeter frame in the closed position. The latching mechanism includes a common multipoint lock tie bar 20 which is mounted along the latching side of the perimeter frame for relative sliding movement in the longitudinal direction of the bar along the frame. The tie bar 20 includes a plurality of first mating connectors 22 mounted at spaced positions therealong. A set of three first mating connectors 22 is shown in the illustrated embodiment.
[0037] The latching mechanism also includes a set of lock keepers comprising second mating connectors 24 mounted at spaced positions along the latching side of the sash. The second mating connectors 24 correspond in number and location to the first mating connectors 22 so as to be similarly spaced for alignment of the first and second connectors in the closed position. The first and second mating connectors are thus arranged to mate with one another respectively to latch or lock the window in the closed position. Slidably displacing the tie bar 20 in the longitudinal direction thereof along the latching side of the frame causes the mating connectors to be selectively engaged with one another in the closed position of the window.
[0038] The reinforcement according to the present invention comprises a plurality of separate reinforcement members 26 which are supported spaced apart from one another along the latching side of the sash for respective alignment with the second mating connectors 24 so that the second mating connectors can be fastened to the sash by fastening to respective ones of the reinforcement members 26 using screws 27 or other suitable threaded fasteners and the like. The reinforcement members 26 are formed of steel or any other suitable material which is stronger than the plastic material forming the sash for better securement of the screws 27 therein when securing the second mating connectors to the sash.
[0039] A hollow channel is formed in the sash to span in the longitudinal direction of the latching side of the sash adjacent the mounting location of the second mating connectors 24 . The reinforcement members 26 are thus slidably received in the channel formed in the frame member of the sash so as to be inserted in series with one another at spaced apart positions therein.
[0040] Each reinforcement member 26 comprises a flat steel bar which is plural times in length that of a corresponding second mating connector 24 which is fastened to it.
[0041] Spacers 28 formed of a dissimilar material, for example PVC plastic, are mounted between each adjacent pair of the reinforcement members 26 to maintain a space therebetween in the mounted position thereof. The spacers are much shorter in the longitudinal direction than the reinforcement members 26 .
[0042] Each spacer 28 is arranged to span the full cross section of the hollow channel receiving the reinforcement members 26 therein to prevent any sliding overlap of the plates within the hollow channel of the sash. Each spacer is thus positioned between the ends of two adjacent reinforcement members.
[0043] The spacers 28 are formed of a soft plastic material which is arranged to be softer than the steel of the reinforcement members 26 as well as being softer than the vinyl forming the frame members of the sash and perimeter frame of the windows. The force required to compress the spacers 28 is arranged to be less that the force in the longitudinal direction of the latching side of the sash which would be required to cause the sash to bow. Accordingly, the spacers are soft enough to allow some deformation thereof rather than allowing bowing of the sash.
[0044] To further ensure that there are no undesirable forces causing the window sash to bow, the combined length of all of the reinforcement members 26 and the spacers in the longitudinal direction of the latching side of the sash is arranged to be shorter than that of the sash so that the spacers and reinforcement members 26 . Accordingly gaps are installed between all of the spacers and the reinforcement members which accommodate for any differences in expansion or contraction between the reinforcement members and the latching side of the sash.
[0045] When more than two second mating connectors 24 are provided, the reinforcement members 26 which are located at opposing ends of the latching side of the sash are arranged to be shorter in the longitudinal direction thereof than any intermediate ones of the reinforcement members 26 .
[0046] The members 26 located adjacent the opposing ends of the sash are also arranged to be longer than the distance between the outermost ones of the second connectors 24 and the respective outer ends of the sash in the longitudinal direction of the latching side to ensure that even when the reinforcement members 26 at the opposing ends are abutted against the respective opposing ends, they still overlap the mounting locations of the two outer second mating connectors 24 .
[0047] Furthermore the intermediate reinforcement members 26 are arranged to have a length which will overlap the respective intermediate ones of the second mating connectors with which they are associated even if all of the reinforcement members are abutted against one another adjacent one end of the latching side of the sash or the other.
[0048] Depending upon the length of the latching side of the sash, a different number of second mating connectors 24 are provided and different lengths of reinforcement members 26 inserted within the hollow interior of the sash frame member are also provided. The following table illustrates the different lengths of reinforcement members 26 which can be used for different lengths of latching sides of the sash. In the illustrated embodiment for example when the tie bar has a length of 34.9 inches, three second mating connectors 24 are provided with three associated reinforcement members 26 . The two outermost members 26 have a length of 8 inches in the longitudinal direction while an intermediate one of the reinforcement members has a length of the 15 inches.
[0000]
TIE BAR
REINFORCEMENT MEMBERS
SIZES
LENGTH AND POSITION
(INCHES)
1
2
3
4
26.9 OR LESS
8″
8″
30.9
8″
13″
8″
34.9
8″
15″
8″
38.9
8″
17″
8″
42.9
8″
19″
8″
46.9
8″
21″
8″
50.9
8″
23″
8″
54.9
8″
25″
8″
58.9
8″
27″
8″
62.9
8″
21″
21″
8″
66.9
8″
21″
21″
8″
70.9
8″
23″
23″
8″
[0049] In order to assemble the sash with the steel reinforcement members 26 inserted therein, the correct number and layout of reinforcement members are selected from the above chart and inserted in order with the spacers 28 abutted therebetween. The latching side of the sash is then positioned to span generally horizontally and can be quickly moved side to side to further separate the steel of the reinforcement members from the spacers 28 to maintain a gap therebetween. The central or intermediate one of the lock keepers forming the second mating connectors 24 can then be fastened to its respective reinforcement member 26 using suitable fasteners therebetween.
[0050] The latching side of the sash is then tilted to one end until the reinforcement member 26 at that end abuts the respective end of the sash. At this point the second mating connector 24 at that bottom end of the sash is then applied with fasteners. The process is then repeated by tilting the sash to the other direction so that the other end is located at the bottom and then the corresponding second mating connector 24 adjacent to that bottom end is then secured to the respective reinforcement member 26 .
[0051] The spacers 28 serve primarily to ensure that the reinforcement members 26 cannot slide past or overlap one another when they are slidably inserted into the hollow channel formed in the sash.
[0052] Since various modifications can be made in my invention as herein above described, and many apparently widely different embodiments of same made within the spirit and scope of the claims without department from such spirit and scope, it is intended that all matter contained in the accompanying specification shall be interpreted as illustrative only and not in a limiting sense. | In an operator window including a perimeter frame supporting a sash therein for movement between respective open and closed positions, a plurality of reinforcement members are mounted within the sash to provide reinforcement to a latching mechanism secured thereto. When the latching mechanism comprises a plurality of separate latching points at spaced positions along a latching side of the sash, a separate reinforcement member is associated with each of the latching points which is independent and maintained in separation from the remaining reinforcement members by spacers mounted therebetween. The spacers ensure sufficient space between the reinforcement members to accommodate for differences in thermal expansion and contraction between the different materials of the reinforcement members and the sash. | 4 |
This is a continuation of Ser. No. 711,734 filed Mar. 14, 1985, now abandoned.
FIELD OF THE INVENTION
This invention relates generally to the art of water heaters and more particularly to an improved residential gas operated water heater.
BACKGROUND OF THE INVENTION
Water heating in residential and commercial establishments has been carried out for many years by providing a burner below a tank of water controlled by a thermostat. In the past, the efficiency of such domestic water heaters was of little concern as natural gas and bottled gas used as an energy source were relatively inexpensive.
The content of the exhaust gases of such water heaters was also of little concern. The gas burned was considered a clean fuel and each installation was so small that products of combustion introduced into the atmosphere by such units were ignored.
The efficiency of all gas consuming appliances has now become more of a concern to both government units and the public at large. Also, the products of combustion of gas have come under government scrutiny, and in some jurisdictions, the amount of certain gases produced by domestic gas water heaters is now the subject of regulation.
Oxides of nitrogen generated by the combustion of fuels are currently the subject of governmental interest and regulation. Oxides of nitrogen are believed to react in the atmosphere to form ozone. Oxides of nitrogen are also believed to react with hydrocarbon pollutants in a complex manner to form chemicals which irritate the eyes and nose and may be harmful. Because of this, emissions of oxides of nitrogen from many sources including water heaters are regulated in the Los Angeles area. Regulation of emission of oxides of nitrogen is becoming more widespread.
Attempts have been made in the past to address the efficiency issue in domestic gas water heaters. U.S. Pat. No. 4,397,296 to Moore, et al., describes a water heater using a combustion chamber surrounded by a body of water to be heated. Such an arrangement minimizes heat loss to the atmosphere from the combustion chamber thereby improving efficiency. While this structure improves efficiency, it increases the cost of manufacturing the water heater because of the complex construction involved.
U.S. Pat. No. 4,301,772 to Eising also proposes to increase efficiency by disposing a combustion chamber within the body of water to be heated. This structure uses a cylindrical combustion chamber inclined with respect to horizontal. Means are provided to deal with water condensed from the products of combustion which gather in this inclined combustion chamber and flow toward the burner opening.
Neither of these patents discusses the reduction of oxides of nitrogen in the products of combustion.
SUMMARY OF THE INVENTION
The present invention contemplates a new and improved water heating apparatus having a high efficiency combustion chamber which reduces production of oxides of nitrogen.
In accordance with the present invention, there is provided a water heating apparatus comprised of a tank adapted to hold a body of water, a combustion chamber within said tank, a barrier obstructing a major portion of the cross-sectional area of the combustion chamber dividing the combustion chamber into a vent portion and a burner portion, a flue tube passing through the tank and communicating with the vent portion of the combustion chamber, and a burner in the combustion chamber burner portion. The barrier in this position causes turbulence in the flame and hot gas flow resulting in an improved heat transfer to the wall of the chamber.
Further in accordance with the invention, the flue tube extends into the combustion chamber to form the barrier dividing the combustion chamber into a burner portion and a vent portion, the flue tube having an opening admitting gases from the vent portion of the combustion chamber only. The gases must then flow around the flue tube before being exhausted.
Further in accordance with the invention, the bottom of the flue tube is closed and the flue opening is disposed a distance above the bottom whereby the flue tube vertical wall surrounds the closed bottom forming a cup-like receptacle at the flue bottom. Such a receptacle collects the water vapor of combustion as it condenses, cooling the gases of combustion and ultimately enabling it to be boiled away.
It is the principal object of the invention to provide a high efficiency gas water heater producing a low level of oxides of nitrogen in its exhaust.
It is a further object of the present invention to provide a high efficiency gas water heater which is inexpensive to manufacture.
It is yet another object of the present invention to provide a high efficiency gas water heater not requiring auxiliary means to dispose of condensate produced in the combustion process.
The invention may take physical form in certain parts and arrangements of parts, a preferred embodiment of which will be described in detail in this specification and illustrated in the accompanying drawings which form a part hereof.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side elevation of a water heater illustrating a preferred embodiment of the present invention with a portion of the water heater cut away and the insulation removed;
FIG. 2 is an enlarged fragmentary view of the combustion chamber; and,
FIG. 3 is a section taken along line 3--3 of FIG. 2 showing the combustion chamber looking from the closed end.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings, wherein the showings are for the purposes of illustrating a preferred embodiment of the invention only and not for the purposes of limiting same, the FIGS. show a conventional water containing tank A having a water inlet 12, a water outlet 13, a pressure relief valve 14 and a drain 15, all in conventional configuration, a combustion chamber C in the lower portion of the tank, and a flue tube F extending vertically from inside the chamber C to and out of the top of the tank A.
Tank A forms no part of the present invention and may take any one of a number of different shapes. In the embodiment shown, it comprises a steel cylinder 11 closed at both ends and having a vertical axis. In the completed state, the tank also has a layer of insulation completely surrounding it and a metal envelope protecting this insulation in a conventional manner. Neither of these elements is shown in the drawings for the purposes of clarity.
The combustion chamber C is generally in the form of a steel tube 22 horizontally disposed within and along a diameter of tank A close to but spaced from the bottom thereof. Tube 22 is preferably of a length to extend substantially across the tank with its inner end closed by a domed closure plate 23 welded thereto.
While the individual exact measurements may vary, in the preferred embodiment, tube 22 is approximately 143/4" long for a 16" diameter, 40 gallon nominal capacity water heater and a 163/4" long for an 18" diameter, 50 gallon nominal capacity water heater. As shown, tube 22 extends 51/2" beyond the central axis of tank A in a 40 gallon water heater and 61/2" beyond the central axis of tank A in a 50 gallon heater. Tube 22 also extends 11/4" out to the side of tank A where it ends in a circular access opening 33.
Flue tube F is in the form of an elongated four inch diameter tube 25 which passes vertically through tank A along its central axis from a point above the top to a point substantially inside of and in the middle of combustion chamber C where it creates a barrier dividing the combustion chamber C into a vent portion 31 and an burner portion 32. Flue tube 25 also has on the inside along its length a conventional baffle 51 which causes turbulence in the hot gases flowing up the flue tube and also helps to conduct heat from these hot gases to the inner walls of the flue tube and thus to the water in tank A.
Vent portion 31 of the combustion chamber is bounded by the lower portion 24 of flue tube 25 and closure plate 23. Burner portion 32 is bounded by the lower portion 24 of flue tube 25 and combustion chamber access opening 33. Lateral open areas 26, 27 and bottom open area 28 around the sides and bottom of the lower portion 24 of flue tube 25 remain available for the passage of gases. However, at its widest point, the lower portion 24 of flue tube 25 occupies more than one-half of the cross-sectional area of combustion chamber C. The lower portion 24 of flue tube 25 is closed by plate 44 and has an inlet opening 43, importantly, facing the vent portion 31 of chamber C. Also importantly, the lower edge of opening 43 is spaced above plate 44 to form a cup 46 which catches and holds any water condensing in the flue tube 25 as the hot gases pass therethrough.
Opening 43 may take a number of shapes and dimensions but is preferably square with its width dimension preferably selected to be one-third the circumference of flue 25. In the embodiment shown, opening 43 is three and one-half inches high, approximately four and one-fifth inches wide and has rounded corners.
Pipe 36 provides gas to a conventional thermostatic control 37 using a conventional water temperature sensing element 38 to control gas flow to burner 39.
Burner 39 is an in-shot type burner located in the open portion 32 of combustion chamber C. Burner 39 projects a large flame into the burner portion of combustion chamber C which is shaped by deflection plate 41 to bathe the walls of combustion chamber C, heating the combustion chamber and the water surrounding it. Such burners are commerically available from sources such as White Rogers and Jade Controls.
Access opening 33 is conventionally closed by sheet metal closure 42 and insulated in the conventional manner.
The flame from burner 39 is obstructed by the lower portion 24 of flue tube 25 and passes there around through lateral open areas 26, 27 and bottom open area 28 into the vent portion 31 of combustion chamber. The flame thus flows through passages having the large cross-sectional area of the burner portion 32, then through a space having a restricted cross-sectional area around flue tube 25 and into the space having a large cross-sectional area of the vent portion 31. The products of combustion enter flue tube 25 through rectangular flue opening 43 communicating with combustion chamber vent portion 31 and are exhausted through flue tube 25.
The flow of the flame produced by burner 39 through the obstructed combustion chamber C causes turbulent combustion. This turbulent combustion is believed to reduce production of oxides of nitrogen.
This turbulence also causes the gases of combustion to repeatedly contact the walls of chamber C which results in good heat transfer to the water while at the same time helping to limit the maximum temperature of the gases.
As the products of combustion go up flue tube 25, heat is extracted from them by the relatively cool surfaces of the flue tube wall and baffle 51 and transferred to the water in tank A. Water vapor contained in the products of combustion condenses on these surfaces, transferring the latent heat of vaporization to them and thus to the water in tank A. The condensed water flows down flue tube 25 into receptable 46. The water cools the lower portion 24 of flue tube 25 and is evaporated by the heat of combustion.
It is believed that the lower portion 24 of flue tube 25 projecting into the combustion chamber C reduces formation of oxides of nitrogen through a number of mechanisms. As previously discussed, the obstruction formed by the lower portion 24 of flue tube 25 induces turbulence in the combustion pattern. This turbulence is believed to reduce formation of oxides of nitrogen directly.
In addition to the direct effects of this turbulence, the turbulence provides more contact of the combustion gases with the walls of the combustion chamber, cooling the flame and the products of combustion. A lower combustion temperature reduces production of oxides of nitrogen.
Also, the condensed water collecting in the cup-like receptacle 46 cools the surface of the lower portion 24 of flue tube 25 in chamber C presenting additional cooled surfaces in the combustion chamber C thereby further lowering combustion temperatures and reducing production of oxides of nitrogen.
The invention has been described with reference to a preferred embodiment. Obviously, modifications and alterations will occur to others upon reading and understanding of this specification. It is intended to include all such modifications and alterations insofar as they come within the scope of the appended claims or the equivalents thereof. | An improved water heater has a submerged combustion chamber providing increased efficiency, lowered production of oxides of nitrogen and ease of manufacture. The water heater has a horizontal cylindrical combustion chamber and a flue tube having a closed bottom penetrating through a major portion of the combustion chamber along a diameter of the combustion chamber causing turbulent combustion. | 5 |
CROSS-REFERENCE TO RELATED APPLICATION
This is a continuation-in-part application of copending application Ser. No. 857,781, filed Dec. 5, 1977 for "Earth Anchor".
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to earth anchors and more particularly, but not by way of limitation, to an earth anchor having extendable anchor arms and a metal skirt attached to the anchor arms which is particularly suited to anchoring objects in soft earth, swamp or marshlands.
2. History of the Prior Art
There have been many innovations in the development of earth anchors for supporting guy wires, anchoring mobile homes and the like. Many of these developments include anchors which have extendable arms and after insertion into an anchoring hole, these arms are extended into the surrounding earth to perform the anchoring function.
However, the prior art anchoring devices have not been totally successful for use in soft earth such as sand and around streams, rivers, lakes and oceans or in swamp or marshlands.
In the construction of pipelines across swamps and the like, the pipelines have been anchored by the sinking of large concrete weights having attachment cables for connecting the pipeline thereto. This method has the obvious disadvantage of requiring large swamp barges for the handling of the concrete blocks. The gradual sinking of these blocks due to their weight and the cost of the blocks and handling thereof cause the cost of laying such pipelines to be extremely high.
One of the primary reasons for the failure of earth anchors in such applications is that in order to make the anchor arms retract into a package small enough to be inserted into a small drilled hole, the anchor arms must be rather narrow. Once these narrow anchor arms are extended into the earth, they simply do not have sufficient cross-sectional area to provide the necessary holding power.
Further, in the use of retractable or extendable anchor arms, there has been a constant danger of the locking mechanism which holds the anchor arms into an extended position, becoming loose and thereby allowing the arms to inadvertently retract and loose their anchoring power.
There have been various screw-type activated anchors such as taught in the patent to Cole et al, U.S. Pat. No. 1,606,147, issued Nov. 9, 1926 for an "Earth Anchor Device" and the patent to Handel, U.S. Pat. No. 2,217,271, issued Oct. 8, 1940 for "Expansible Earth Anchor". However, these anchors have an inherent disadvantage in that the threaded rod used for expanding the anchor after expansion, is subject to exposure to the elements and becomes rusty or corroded. Since the threaded rod is often the mechanism which locks the arms in the extended position, corrosion will destroy the locking feature in a relatively short period of time.
A further disadvantage of the subject patent is the limitation on the surface area caused by the shape and size of the anchor arms in conjunction with the hole size into which they are to be inserted.
SUMMARY OF THE INVENTION
The present invention provides an earth anchor having an extendable anchoring mechanism and which can be positively locked in its extended position. The means for locking the mechanism in an extended position is fully protected from corrosion which naturally extends the expected life of the anchor when used in a corrosive environment.
The anchor generally comprises an elongated anchor rod having the inner end portion threaded over a specific length. A first plate member is slidably disposed on the threaded rod, the upper outer surface of the plate being in engagement with a flanged boss member which is rigidly connected to the rod for rotation therewith, said flange portion being utilized to force the plate member downwardly and expanding the anchor arms as will be hereinafter set forth.
A plurality of anchor arms are pivotally attached to the lower or inner surface of the plate member and extend downwardly and may be folded into a pattern no longer than the surface area of the plate member. A substantially cylindrical-shaped metal skirt member is pleated into a smaller cylindrical shape and attached to the outer surface of the anchor arms so that said anchor arms with their attached skirt members are initially folded in a cylindrical shape having diameter no greater than the plate member.
A second plate member is threadably disposed on the rod near the inner end of the rod and is of approximately the same diameter as the first mentioned plate member. The outer or upper surface of the second plate member is placed in engagement with the inner surface or ends of the anchor arms. A substantially conical or tapered housing is provided on the bottom or inner surface of the second plate member and is of a length substantially equal to the length of the threaded portion of the anchor rod for receiving the anchor rod therein.
The outer periphery of the conical-shaped housing is provided with a plurality of auger ribbon flights so that the entire anchor arm mechanism may be augered in soft earth without the requirement of having first drilled a hole in order to seat the anchor means.
It is noted that should a pre-drilled hole be used for seating this anchor, it would be unnecessary to have the auger ribbon flights around the outer periphery of the housing.
In the case where the auger ribbon flights are used however, there is a locking mechanism cooperating between the second plate member and the threaded rod in order to lock said members for simultaneous rotation during the augering operation in order to get the anchor to the desired depth.
After the device has been augered into its desired depth, the anchoring rod may be rotated in a reverse direction which disengages the locking mechanism and after that, rotation of the anchoring rod will cause the rod to threadably travel through the second plate member and into the housing thereby pushing the first plate member downwardly toward the second plate member which causes the anchoring arms to be expanded into the earth.
As the arms expand into the earth, the skirt member travels with the arms and opens to form an enlarged surface area to provide greater holding power for the anchor. The anchor arm mechanism is designed so that when the anchor arms are in their fully extended position, they extend slightly upward whereby the upper surface skirt member is concave. This is felt to provide better holding power.
In some cases where the consistency of the earth is something more solid than marshland or loose sand, some difficulty is encountered in expanding the anchor arms and associated skirt member when the outer surface of the anchor arms are configured substantially straight.
Therefore, the present invention includes embodiments wherein the outer surface of the anchor arms are curved to form a concave shape whereby upon extension into the earth, they will move through the surrounding earth in an arcuate path with a minimum amount of disturbance. In the expanded position the outer surface or upper surface of the skirt member will then form a more accented concave surface.
Another feature of all of the embodiments of the invention includes the fact that when the arms and skirt member are in the fully extended position, the inner edge of the skirt member will still be in a pleated condition. The design of the diameter of the plate members in conjunction with the inner edge of the skirt member are such that the first and second plate members, in the fully extended position tend to sandwich the inner edge of the skirt member therebetween to provide additional stability when a pulling force is applied to the anchor.
DESCRIPTION OF THE DRAWINGS
Other and further advantageous features of the present invention will hereinafter more fully appear in connection with a detailed description of the drawings in which:
FIG. 1 is a side elevational view of an earth anchor embodying the present invention.
FIG. 2 is a sectional elevational view of the earth anchor of FIG. 1.
FIG. 3 is a sectional bottom view of the anchor of FIG. 1 taken along the broken lines 3--3 of FIG. 1.
FIG. 4 is a plan view of the earth anchor of FIG. 1 in an expanded position.
FIG. 5 is a sectional elevational view of the earth anchor of FIG. 4 taken along the broken lines 5--5 of FIG. 4.
FIG. 6 is an end sectional view of a locking mechanism provided between the anchor rod and expanding plate of the embodiment of FIG. 1.
FIG. 7 is a sectional elevational view of the locking mechanism of FIG. 6 taken along the broken lines 7--7 of FIG. 6.
FIG. 8 is a plan sectional view of the locking mechanism of FIG. 6 shown in the second unlocked position.
FIG. 9 is a sectional elevational view of a second embodiment of the earth anchor wherein the outer surface of the arcuate arms and associated skirt member are provided with a concave arcuate shape.
FIG. 10 is a sectional elevational view of the embodiment of FIG. 9 shown in an expanded position.
FIG. 11 is an elevational view of the third embodiment of the invention showing a modification of the concave arcuate arms.
FIG. 12 is a plan view of the embodiment of FIG. 11 in an expanded position.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to the drawings in detail and particularly to FIGS. 1 through 8, reference character 10 generally indicates an earth anchor which is particularly adaptable for use in anchoring objects in soft earth, sand, swamp or marshlands.
The anchor 10 generally comprises an elongated anchor rod 12, the outer end of which may be fitted with a suitable handle member 14 which, after seating the anchor, may be replaced by an anchor hook or other attachment device (not shown).
The inner end portion of the anchor rod 12 is provided with an elongated threaded segment 16 as shown in FIG. 2. A collar member 18 is rigidly secured to the rod 12 near the outer end of the threaded portion 16 and is provided with an outwardly extending flange member 20 at the lower end thereof.
A first circular plate member 22 is slidably disposed on the threaded portion of 16 of the rod 12, the upper surface of the plate 22 being engagable with the lower surface of the flange member 20.
A plurality of elongated anchor arms 24 are pivotally secured to the lower surface of the plate member 22 by a suitable downwardly extending ear member 26 and associated pivot pins 28.
The anchor arms 24 have arcuate inside surfaces 30 which extend from the outer ends of the anchor arms toward the pivot pins 28 and terminating in a shaped land portion 32 for a purpose that will be hereinafter set forth.
A metal skirt member 34 having a circular cylindrical shape is pleated to form a smaller cylindrical shape having diameter approximately equal to the diameter of the plate member 22. The skirt member 34 in its pleated shape as shown in FIGS. 1 and 2 is rigidly secured to the outer surfaces of the anchor arms 24 as shown in FIG. 2.
The upper or inner edge 36 of the skirt member 34 extends at least as high as the pivot pins 28 for a purpose that will be hereinafter set forth.
A second circular plate member 38 is threadedly secured to the lower end of the threaded portion 16 of the rod 12. The upper outside edge of the plate member 28 is beveled at 40 and is initially disposed in contact with the arcuate surface 30 of the anchor arms 24 wherein said beveled portion 40 is substantially in contact with the outer ends of said anchor arms 24.
A plurality of upwardly extending anti-rotation stop members 39 and 41 are secured to the upper surface of the plate member 38 and are positioned adjacent the lower or outer ends of the arms 24 for a purpose that will hereinafter be set forth.
A substantially conical shaped housing member 42 is secured to the lower surface of the plate member 38, the upper end of said housing being in open communication with the lower end of the threaded portion 16 of the rod 12. The length of the housing 42 is substantially the same length as the threaded portion 16 of the rod 12 for receiving said threaded portion 16 fully inside the housing in a manner that will be hereinafter set forth. The lower end of the housing member 42 is pointed at 43 for easy insertion into the earth and the outer periphery of said housing is provided with one or more auger ribbons 44 and 46.
A locking member generally indicated by reference character 48 is operably connected between the threaded portion 16 of the rod 12 and the upper surface of the plate member 38. Referring to FIGS. 6, 7 and 8, the locking mechanism 48 comprises a block member 50 which is rigidly secured to the upper surface of the plate 38 in a position near the threaded portion 16 of the rod 12.
The block member 50 is provided with a rectangular transverse aperture 52 for slidably carrying a pin member 54, also having a rectangular cross-sectional shape. The outer end of the pin member 54 is provided with a flange 56 to limit the travel of the pin member toward the threaded portion 16 of the rod 12. The inner end of the pin member 54 is provided with a truncated surface 58 set at an angle as shown in FIGS. 6 and 8.
A transverse bore 60 is provided through the rod 12 for receiving the truncated end portion 58 of the pin 54 therein when the anchor is in its retracted position as shown in FIG. 2.
In operation, the earth anchor 10 is configured for insertion into the ground as shown in FIGS. 1 and 2 with the anchor arms fully retracted and the skirt member, in its pleated state, being cylindrical in shape with diameter no larger than the plate members 22 and 38. The locking pin 54 is extended into the bore 60 of the anchor rod 12 with the truncated surface 58 being positioned partly into the bore 60 as shown in FIG. 6. The pointed end 43 of the housing 42 is then inserted into the ground until the auger ribbon flights 44 and 46 contact the soft earth. The handle member 14 is then utilized to force the earth anchor into the ground with a twisting motion so that the ribbon flights 44 and 46 cause the earth anchor to move downwardly into the earth while the pin member 54 prevents rotation of the rod 12 with respect to the threaded plate member 38.
After the earth anchor has been moved to the desired depth, the rod 12 is then rotated in an opposite direction, typically for less than a quarter of a turn, which causes the edge of the bore 60 of the rod 12 to force against the truncated portion 58 of the pin member 54 causing the pin member 54 to slide out of contact with the rod 12 as shown in FIG. 8.
The rod then is again rotated in its original direction, and since the pin member 54 is no longer in contact with the rod 12, the plate member 38 and associated housing 42 remain stationary, thereby threadedly receiving the rod 12 into the interior of the housing 42. It is noted at this point that after the bore 60 has passed the pin member 54 and starts moving into the housing 42, the bore 60 is no longer in alignment with the pin member 54 thereby preventing the pin member from substantially reinserting back into the bore 60.
As the threaded rod 12 is moved downwardly into the housing 42, the collar member 18 and associated flange member 20 force the plate member 22 in a downward direction with respect to the plate member 38. At this point the inside convex surface 30 of the anchor arms 34 move in sliding contact with the bevel portion 40 of the plate member 38 thereby forcing the anchor arms outwardly into the earth. As the anchor arms 24 move outwardly into the earth, they pull the skirt member 34 therealong and the lower or outer portion of the pleats in the skirt member start straightening.
When the outer ends of the anchor arms 24 first enter the undisturbed surrounding earth, they are prevented from any rotation about the rod axis. If the plate 38 then attempts to rotate due to friction in the threads, such rotation is prevented by the anti-rotation stop members 39 and 41. Throughout the entire extending operation the convex surface 30 of the anchor arms 24 move along the edges of the stop members 39 and 41 positively preventing any rotation of the plate 38 and associated housing 42.
The diameter of the skirt member 34 in its unpleated form, is configured to be substantially equal to the diameter of the outer edge 37 of the skirt member when the anchor arms 24 reach a substantially right angle position with respect to the rod 12 as shown in FIG. 5.
However the shape of the lands 32 near the inner end of the anchor arms 24 are such that when the plate members 22 and 38 are moved together, the anchor arms 24 go just past their right angle position to form a concave upper surface of the arms and associated skirt member 34 as shown in FIG. 5 and as indicated by reference character 58. It is also noted that since the upper or inner edge 36 of the skirt member extends substantially opposite the pivot pins 28, the inside edge 36 of the skirt member which is still in its pleated form even when extended is sandwiched between the plate members 22 and 38 which provides added stability and holding power to the extended skirt member when an outward or pulling force is applied to the anchor rod 12.
The portion of the threads above the plate member 38 may be coated with an anti-corrosion compound but as the rod threads move the plate 38 threads, this coating is disturbed. However, it is also noted that since the lower end of the threaded portion 16 of the rod 12 has fully extended into the housing 42 as shown in FIG. 5, it is protected from the corrosive nature of the soil into which the anchor has been inserted.
It is further noted that without further rotation of the rod 12, the anchor is locked in its extended position and cannot be inadvertently unlocked without positive rotation of the rod 12.
If it is desired to remove the anchor from the earth, the rod 12 is rotated in a way such that the collar member 18 and associated flange members 20 are moved upwardly with the rod 12 thereby no longer forcing the plate member 22 toward the plate member 38.
It if becomes difficult or impossible to remove the anchor from the earth, the rod 12 may be continually rotated until it dislodges from the plate 38 and the rod 12 may then be simply pulled from the earth.
Referring now to FIG. 9, reference character 62 generally indicates a second embodiment of the earth anchor which operates in a substantially identical manner to that of the earth anchor 10.
However in this case, anchor arms 64 are provided with an arcuate outer concave shape 66 and are provided with a shaped pleated skirt member 68.
The shape of the arcuate anchor arms 66 and associated skirt member 68 will provide for easier expansion after the anchor has been lowered into the earth to its desired distance as shown in FIG. 10. It can be seen that as the anchor arms 64 are being extended into the undisturbed earth indicated by reference character 70, the curved configuration of the anchor arms will cause the anchor arms and associated skirt member to more accurately move through the curved path created by the outer ends of the anchor arms as they are moving downwardly and outwardly during the expanding operation.
It can be seen in FIG. 10 that after the earth anchor has been fully inserted into the ground and the arms thereof expanded, that the outer surface of the skirt member 68 is in contact with undisturbed earth, the only substantial earth disturbance being directly above the center part of the anchor mechanism which was created when the device was augered into the earth and as generally shown by reference character 72.
Referring now to FIGS. 11 and 12, reference character 74 generally indicates a modification of the embodiment 62 having anchor arm members 76, the outer edge thereof being concave by virtue of three straight segment portions 78, 80 and 82. The embodiment 72 is provided with pleated skirt segments 84, 86 and 88 which are secured to the outer surface edge of the anchor arm segments 78, 80 and 82, respectively.
The configuration of the anchor arm 74 provides substantially the same benefit as that of 62 in that as the anchor arms are being extended into the earth, they follow a curvelinear path resulting in a minimal disturbance of the earth and less resistance to the expanding force.
FIG. 12 depicts the anchor arms 76 and associated skirt segments 84, 86 and 88 in a fully expanded position. It is also noted that the inner edge 90 of the skirt segment 84, in its expanded position, is sandwiched between upper and lower plate members 22 and 38.
The portions of the embodiments described in FIGS. 9 through 12 which are common to the embodiments shown in FIGS. 1 through 8 carry the same reference character numbers for purposes of simplicity.
From the foregoing it is apparent that the present invention provides an earth anchor which is particularly suitable for anchoring objects in sand and soft earth such as marshlands, swamps and the like.
Whereas, the present invention has been described in particular relation to the drawings attached hereto, other and further modifications apart from those shown or suggested herein may be made within the spirit and scope of the invention. | An earth anchor for securing objects in soft earth and including a plurality of anchor arms which are extendable after the anchor is moved into position. A flexible, pleated, metal skirt member is attached to the anchor arms whereby after being augered into position, the anchor arms and skirt member may be extended into substantially undisturbed earth thereby providing an anchoring surface at least as great as the surface area of the skirt member. | 4 |
FIELD OF INVENTION
This invention relates generally to a digital phase detector. In particular, it relates to an asynchronous digital phase detector which is configured to minimize the size of a phase detector dead zone.
BACKGROUND
Digital phase detectors are used in phase-locked loops and delay-locked loops. Phaselocked loops circuits are widely used in electronic systems to generate an accurate replica of an incoming signal, or for frequency synthesis. For example, in a computer, a phase-locked loop is to used by a microprocessor to generate an on-chip clock signal from an off-chip clock signal. Within the phase-locked loop, the digital phase detector is used to generate an error voltage proportional to the phase difference between a reference signal and a signal generated by a voltage controlled oscillator (VCO). The error voltage is use to tune the VCO so that the VCO is phase locked with the reference signal.
Delay-locked loops are also widely used in electronic systems. Delay-locked loops can be used realign the edges of internal clock and data signals which have been skewed during the distribution of the signals. Circuitry through which the internal clock and data signals are distributed induce undesirable delay which causes clock and data signals to reach destination circuit elements delayed in time. The delay-lock loop provides additional delay in the distributed signals so that the edges of the signals are aligned with, for example, a master clock signal. Within a delay-locked loop, the phase detector is used to generated an error signal which is proportional to the phase difference between the master clock and the distributed signal. Typically, the error signal is used to tune a programmable delay line which re-aligns the edges of the distributed signal with the master clock.
FIG. I shows a digital phase detector 10 which includes a reference clock input Ref -- CLK, a feedback signal input FDB -- CLK and an output Detector -- Out. The digital phase detector 10 generates a signal at the output Detector -- Out which reflects the phase differences between the reference clock input Ref -- CLK and the feedback signal input FDB -- CLK. Generally, the signal Detector -- Out at the output of the digital phase detector 10 will only change states or voltage levels upon the occurrence of an edge or a voltage potential level of either the signal input Ref -- CLK or the signal input FDB -- CLK.
FIG. 2 includes Traces 2A, 2B, 2C which represent signals at the inputs and the resultant output of the digital phase detector 10 shown in FIG. 1. Trace 2A shows a reference clock input Ref -- CLK signal. Trace 2B shows a feedback signal input FDB -- CLK signal. Trace 2C shows an output Detector -- Out response to the inputs shown in Traces 2A, 2B.
Some key features of the signals should be noted. First, if the output Detector -- Out is at a lower of two states upon the occurrence of a positive edge at the reference clock input Ref -- CLK signal, the output Detector -- Out will transition to a higher state. If the output Detector -- Out is at the higher of the two states upon the occurrence of a positive edge at the reference clock input Ref -- CLK signal, the output Detector -- Out will remain at the higher state. If the output Detector -- Out is at the higher state upon the occurrence of a positive edge at the feedback signal input FDB -- CLK signal, the output Detector -- Out will transition to the lower state. If the output Detector -- Out is at the lower state upon the occurrence of a positive edge at the feedback signal input FDB -- CLK signal, the output Detector -- Out will remain at the lower state. Further, if the reference clock input Ref -- CLK signal and the feedback signal input FDB -- CLK signal both transition from the lower state to the higher state at approximately the same time, the output Detector -- Out toggles to the one of the two states the output Detector -- Out is not in upon the transition of the two inputs.
Dashed lines 20, 24 show the output Detector -- Out transitioning to a high state due to a positive edge transition of the reference clock input Ref -- CLK signal. Dashed lines 22, 26, 32 show the output Detector -- Out transitioning to a low state due to a positive edge transition of the feedback signal input FDB -- CLK signal. Dashed lines 28, 30 depict a dead zone of the digital phase detector. The output Detector -- Out of the phase detector will toggle due to the occurrence of positive transitioning edges of both the reference clock input Ref -- CLK signal and the feedback signal input FDB -- CLK signal within the dead zone of the digital phase detector. The dead zone of the phase detector is the period of time defined by the dashed lines 28, 30 in which the output Detector -- Out of the phase detector will toggle if the two inputs transition high. If the positive edges of the two inputs are separated apart in time so that either positive edge is not in the dead zone time defined by the dashed lines 28, 30, the output Detector -- Out will not toggle. Rather, the phase detector will respond to positive edge transitions of the inputs as previously described.
The larger the size of the dead zone period of time defined by the dashed line 28, 30, the lower the operational frequency of the digital phase detector. Therefore, it is desirable to minimize the size of the digital phase detector dead zone.
The reference clock input Ref -- CLK signal to the digital phase detector can be noisy. Prior art digital phase detectors either require a limitation on the amount of noise within the reference clock input signal, or additional circuitry is required to filter the reference clock input signal.
The prior art digital phase detectors as shown in FIG. 1 can experience instabilities. The instabilities can increase the time required to obtain lock in either phase-locked loops or delay-locked loops.
It is desirable to have a digital phase detector which offers high sensitivity and provides a phase detector dead zone that is smaller than previously possible. The digital phase detector would provide filtering of the reference clock signal input to the digital phase detector. Further, the digital phase detector would provide a reset condition to avoid instabilities of the digital phase detector.
SUMMARY OF THE INVENTION
The present invention includes an asynchronous digital phase detector. Digital logic and the structures of transistors within the phase detector provide a digital phase that has better sensitivity than presently existing phase detectors. Additionally, the digital phase detector has a smaller dead zone than presently existing phase detectors. The smaller dead zone allows the phase detector to properly phase detect high frequency signals. Further, the digital phase detector provides filtering of the reference clock input. Finally, the digital phase detector can include a reset input which allows avoidance of instabilities of the phase detector.
A first embodiment of the invention includes a phase detector. The phase detector includes a phase compare logic block. The phase compare logic block receives a reference signal (RS) and a feedback signal (FS). The compare logic block generates an output signal at a first of two output states when the reference signal transitions from a first voltage potential to a second voltage potential. The compare logic block generates an output signal at a second of two output states when the feedback signal transitions from the first voltage potential to the second voltage potential. The compare logic block toggles the output signal between the first state and the second state when reference signal and the feedback signal transition from the first voltage potential to the second voltage potential at substantially the same time. The phase compare logic block filters more signal noise from the reference signal than from the feedback signal.
A second embodiment of the invention is similar to the first embodiment. For the second embodiment, the phase compare logic block includes an asynchronous state machine which changes states upon the occurrence of a positive reference signal transition, and upon the occurrence of a positive feedback signal transition.
A third embodiment of the invention is similar to the first embodiment. The third embodiment includes a reset signal which drives the output signal to the first state.
Other aspects and advantages of the present invention will become apparent from the following detailed description, taken in conjunction with the accompanying drawings, illustrating by way of example the principles of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a digital phase detector.
FIG. 2 shows waveforms which represent signals at the inputs and the output of the digital phase detector shown in FIG. 1.
FIG. 3 shows an embodiment of the invention which includes a reset input.
FIG. 4 shows an embodiment of the invention in which includes four quadrants of digital logic.
FIG. 5 is a table which depicts the present states and next states of an asynchronous state machine of the invention.
FIG. 6 shows another embodiment of the invention in which the logic functions shown in FIG. 4 have been implemented with pass-transistors.
DETAILED DESCRIPTION
As shown in the drawings for purposes of illustration, the invention is embodied in an asynchronous digital phase detector. The digital phase detector include logic circuitry which increases the sensitivity of the phase detector. Additionally, transistors within the phase detector which are used to implement the logic circuitry can be scaled to further improve the sensitivity of the phase detector. The improved sensitivity of the phase detector provides the phase detector with a smaller dead zone and allows the phase detector to operate at higher frequencies.
FIG. 3 shows a digital phase detector 40 according to the invention which includes a reset input Reset. When activated, the reset Reset input places the digital phase detector 40 in a predefined state. Typically, the output Detector -- Out is reset to a low voltage potential when the reset input Reset is activated. The reset input Reset can be activated to initialize the digital phase detector 40 to a known state. By avoiding instable conditions, phase-locked loops and delay-locked loops which include the digital phase detector 40 can lock faster.
FIG. 4 shows an embodiment of the invention in which includes a digital phase detector 40 having four quadrants 42, 44, 46, 48 of digital logic. The digital logic within each quadrant 42, 44, 46, 48 is selected so that for a given fabrication process (for example, CMOS), the digital phase detector 40 is less sensitive to one input than the other. The reduced sensitivity acts to low pass filter the input signal. The digital phase detector receives a reference clock input Ref -- CLK and a feedback signal input FDB -- CLK. The digital phase detector 40 generates a detector output Detector -- Out. Generally, the less sensitive input receives the reference clock input Ref -- CLK which can be noisy. Reducing the sensitivity of one of the phase detector inputs improves the sensitivity of the phase detector which reduces the size of the dead zone.
A first quadrant 42 generates a first quadrant output y1. A second quadrant 44 generates a second quadrant output y2. A third quadrant 46 generates a third quadrant output y3. A fourth quadrant 48 generates a fourth quadrant output y4. The four quadrants 42, 44, 46, 48 can each be configured to receive the reference clock input Ref -- CLK, the feedback signal input FDB -- CLK, the first quadrant output y1, the second quadrant output y2, the third quadrant output y3, the fourth quadrant output y4, and the Reset signal This embodiment includes the digital phase detector output Detector -- Out being the first quadrant output y1.
The logic within the first quadrant 42 is:
y1=(Ref -- CLK·FDB -- ·y1+Ref -- CLK·FDB -- CLK·y2+Ref -- CLK·FDB -- CLK·y3+Ref -- CLK·FDB -- CLK·y4)·Reset.
The logic within the second quadrant 44 is:
y2=(Ref -- CLK·FDB -- CLK·y1+Ref -- CLK·FDB -- CLK·y2)·Reset.
The logic within the third quadrant 46 is:
y3=(Ref -- CLK·FDB -- CLK+Ref -- CLK·FDB -- CLK·y1+Ref -- CLK·FDB -- CLK·y3)·Reset.
The logic within the fourth quadrant 48 is:
y4=(Ref -- CLK·FDB -- CLK+Ref -- CLK·FDB -- CLK+Ref -- CLK·FDB -- CLK+Ref -- CLK+y1+Ref -- CLK·FDB -- CLK·y3)·Reset.
The embodiment shown in FIG. 4 includes four quadrants 42, 44, 46, 48 of logic. Four quadrants 42, 44, 46, 48 were selected due to ease of partitioning the required logic. However, more or less quadrants may be included as will become more apparent with the additional description of the operation of the invention as provided below.
The logic within each quadrant 42, 44, 46, 48 is selected so that the inputs connected to the phase detector will generate an output similar to Trace 2C of FIG. 2. A state diagram can be generated which includes a number of states which will ensure the desired functionality. The transition from one state to another is triggered by the occurrence of a positive transition of either the reference clock Ref -- CLK or the feedback signal FDB -- CLK inputs. From the state diagram, the required logic can be determined.
FIG. 5 is a state table which depicts the states of an asynchronous state machine of the invention. The table depicts present states and next states. The next states are dependent upon the status of the inputs of the digital phase detector. The output of the digital phase detector is dependent upon the state of the asynchronous state machine of the digital phase detector.
This embodiment includes four states S, T, U, V. State S corresponds to the first quadrant output y1 being 0 (low), the second quadrant output y2 being 0 (low), the third quadrant output y3 being 1 (high) and the fourth quadrant output y4 being 1 (high). State T corresponds to the first quadrant output y1 being 1 (high), the second quadrant output y2 being 0 (low), the third quadrant output y3 being 0 (low) and the fourth quadrant output y4 being 1 (high). State U corresponds to the first quadrant output y1 being 1 (high), the second quadrant output y2 being 1 (high), the third quadrant output y3 being 1 (high) and the fourth quadrant output y4 being 1 (high). State V corresponds to the first quadrant output y1 being 0 (low), the second quadrant output y2 being 0 (low), the third quadrant output y3 being 0 (low) and the fourth quadrant output y4 being 0 (low).
The table of FIG. 5 depicts the inputs Ref -- CLK, FDB -- CLK as 00, 01, 11 and 10.
These include all of the possible combinations of the inputs. The table also depicts the next states for each present state for each of the possible inputs. For example, for a present state S, the next state with an 00 input is S, the next state with an 01 input is S, the next state with an 11 input is U and the next state with an 10 input is T. The table also depicts the output Detector -- Out for each of the next states. That is, the output Detector -- Out is 0 (low) for state S, the output Detector -- Out is 1 (high) for state T, the output Detector -- Out is 1 (high) for state U, the output Detector -- Out is 0 (low) for state V.
The information provided in FIG. 5 can be used to generate the logic required to implement the asynchronous state machine of the invention. The logic can be generated through hand calculations or through the use of a logic design application program. The logic can be divided into quadrants for ease of partition.
The sensitivity of the phase detector for various configurations of logic within each 30 quadrant 42, 44, 46, 48 is determined through computer aided design (CAD) simulation. Many different logic configurations are simulated to determined which configuration is optimal. That is, various logic configurations are simulated to determine which logic configuration yields a phase detector design having the smallest dead zone. Once the desired functionality of the logic has been determined, it is an iterative process to simulate the response of many possible logic configurations to determine which configuration is the best.
The placement of the logic circuitry on an integrated circuit substrate further affects the sensitivity of the phase detector and the dead zone. CAD simulations of the logic circuitry must include an iterative process of simulating many different configurations of layouts of the logic circuitry on an integrated circuit substrate. Both the logic configuration and the layout of the logic configuration on a substrate which provide the best phase detector sensitivity and the smallest dead zone is determined through CAD simulation.
The logic functions included within each of the quadrants 42, 44, 46, 48 are determined by the optimization process described above. Once the logic functions have been determined, the logic functions can be implemented according to many different digital logic synthesis methods.
FIG. 6 shows another embodiment of the invention in which the logic functions shown in FIG. 4 have been implemented with pass-transistors Q1-Q8, Q9-Q16, Q21-Q28, Q29-Q36, reset transistors Q18, Q20, Q38, Q40 and pull up transistors Q17, Q19, Q37, Q39. Implementation with pass-transistors offers several advantageous features. First, the delay of a signal passing through a pass transistor is minimal. Secondly, the widths of the pass-transistors of FIG. 6 can modified to fiurther to improve the sensitivity of the phase detector.
The input connections to each quadrant is different. However, the electronic circuitry within each quadrant is the same. The output of the digital phase detector is the output y1 of the first quadrant 42. The input connections to each quadrant are determined by the logic functions to be implemented by the quadrant.
In FIG. 6, the reference clock input is designated as IN1, and the feedback signal input is designated as IN2. FIG. 6 also includes signal designations IN1b, IN2b and y1b which are the IN1, IN2 and y1 inputs inverted.
The embodiment shown in FIG. 6 also includes invertors 71, 73, 75, 77, 79, 81, 83, 85. The invertors 71, 73, 75, 77, 79, 81, 83, 85 are standard two transistor invertors which include an N-channel FET and a P-channel FET. The embodiment shown in FIG. 5 further includes a power supply VDD and a circuit ground GND.
This embodiment includes equivalent transistors of each quadrant being the same size, but the transistors within each quadrant being variable sized. That is, Q1 of the first quadrant is the same size as Q9 of the second quadrant, Q21 of the third quadrant and Q29 of the fourth quadrant. However, Q1 of the first quadrant is not necessarily the same size as Q17 of the first quadrant. However, Q17 of the first quadrant is the same size as Q19 of the second quadrant, Q37 of the third quadrant and Q39 of the fourth quadrant.
An embodiment of the invention includes the digital phase detector being fabricated by a 0.35 micron technology fabrication process. This embodiment includes the channel lengths of transistors QI-Q16, Q18 being about 0.35 microns. Further, the channel lengths of the transistors within the invertors 71, 73 are all about 0.35 microns. The channel length of the pull up transistor Q17 is 2 microns. As was previously mentioned, the transistors in the second, third and fourth quadrants 44, 46, 48 are the same size as the equivalent transistors in first quadrant 42.
This embodiment includes the channel widths of transistors Q1-Q8 being 10 microns. Further, the channel width of transistor Q17 is 1 micron, the channel width of Q18 is 5 microns. The inverter 71 includes an N-channel FET having a channel width of 5 microns and a P-channel FET having a channel width of 10 microns. The inverter 73 includes an N-channel FET having a channel width of microns and a P-channel FET having a channel width of 16 microns.
As was previously mentioned, the logic within the four quadrants is selected to change the state of the digital phase detector asynchronous state machine upon the occurrence of a positive transition of either the Ref -- CLK input or the FDB -- CLK input. A first delay T1 is the delay time required for the Ref -- CLK input to influence the output Detector -- Out. A second delay T2 is the delay time required for the FDB -- CLK input to influence the output Detector -- Out. Both the first delay T1 and the second delay T2 define the dead zone of the digital phase detector. This embodiment includes the first delay time T1 being greater than the second delay time T2.
The first delay time T1 defines the dead zone of the digital phase detector if the output of the phase detector is low. The second delay time T2 defines the dead zone of the digital phase detector if the output of the phase detector is high. For the embodiment described, the first delay time T1 is approximately 250 picosecond, and the second delay time T2 is approximately 100 picoseconds.
CAD simulation can be used to determine channel widths of the pass transistors which improve the first delay time T1 and the second delay time T2. By allowing the channel widths of the pass transistor to vary from 5 microns to 15 microns, a first delay time of approximately 100 picoseconds and a second delay time of approximately 50 picoseconds have been measured. Therefore, the dead zone of the digital phase detector 40 has been correspondingly reduced. These measured delay time T1, T2 can be further reduced with greater CAD simulation.
Although specific embodiments of the invention have been described and illustrated, the invention is not to be limited to the specific forms or arrangements of parts so described and illustrated. The invention is limited only by the claims. | An asynchronous digital phase detector. The digital phase detector includes an asynchronous state machine which simulates an edge triggered J-K flip flop. Additionally, the digital phase detector includes a reset line. The asynchronous state machine is implemented with logic which provides for optimal phase detector sensitivity and minimal dead zone. The logic within the digital phase detector is implemented with pass-transistors. The channel widths of the pass-transistors are selectively widened or narrowed to further increase the sensitivity of the phase detector. | 7 |
FIELD OF THE INVENTION
The invention relates to electro-magnetic tackers, particularly power-driven tackers which can carry out a limited number of driving strokes when the main switch is actuated.
BACKGROUND OF THE INVENTION
It is known in a power-driven tacker to mount the staple magazine to be movable between a blocking position and an operating position. In the blocking position, the magazine outlet end for the staples is pivoted downwards away from the tacker housing. In the operating position, the outlet end of the magazine is pivoted upwards into a position adjacent the tacker housing.
German Utility Model No. 8,303,460 discloses such an electro-magnetic tacker in which the actuator element of the main switch is connected to an elongate coupling element which extends downwards to just above the staple magazine. In the blocking position of the staple magazine, a blocking element fastened pivotably to the housing engages into a locking recess in the elongate coupling member. When the staple magazine is pivoted into the operating position, the blocking element pivots as a result, so that the coupling element is released and the actuator element can be displaced to actuate the main switch. The tacker carries out a driving stroke only when the staple magazine is in its operating position, that is to say when the outlet of the staple output channel is placed on a workpiece. The tacker is electronically controlled, and carries out a driving stroke whenever the actuator element is actuated. To execute a further driving stroke, the tacker has to be lifted off from the workpiece and replaced, whereupon a further staple is driven into the workpiece by means of the following driving stroke.
German Offenlegungsschrift No. 2,823,248 discloses a tacker which is controlled by electronics and which, when the main switch is actuated, carries out a specific number of driving strokes, but more than one stroke so that a staple or a nail can be driven even into a relatively hard workpiece. For this purpose, the actuator element of the main switch has coupled to it a staple blocking means which is displaced as a result of actuation of the actuator element, in such a way that it prevents the front staple or the front nail from subsequently being transferred from the staple magazine into the staple output channel. Thus, the driver strikes the same staple or the same nail several times, without further staples or nails being fed into the staple output channel. To start a new operating cycle, the actuator element of the main switch must be released, as a result of which the staple blocking means releases the front staple or the front nail from the staple magazine so that it then enters the staple output channel. When the actuator element is actuated again, a further sequence of driving strokes can be triggered.
French Patent Specification No. 1,290,830 discloses a tacker in which the number of driving strokes is controlled as a function of the driving depth which is reached. For this purpose, this tacker too has a staple blocking means which is connected to the actuator element of the main switch and which, during a cycle of driving strokes, prevents a staple or a nail from being conveyed out of the staple magazine into the staple output channel. When the main switch of the tacker supplied with direct-current voltage is closed, successive driving strokes are triggered. When the predetermined driving depth is reached, an angle fastened to the drive-solenoid armature connected firmly to the driver engages with a toggle lever mounted pivotably on the actuator element and pivots this toggle lever in such a way that the main switch is opened. It is possible to reclose the main switch by actuating the actuator element only after the latter has been released and thus, as a result of the release of the staple blocking means, a new staple or a new nail has been transported into the staple output channel.
SUMMARY OF THE INVENTION
It is observed, according to the invention, that when tackers are used, it can happen that a staple or nail to be driven in is still not driven into the workpiece completely after one or more driving strokes have been carried out, but this is noticed only after the tacker has been lifted off.
The object of the invention is to provide a tacker which can be replaced on a staple or nail not completely driven in, and can drive this staple or nail further into the workpiece.
Accordingly, there is provided by the present invention a power driven tacker which carries out a limited number of driving strokes upon actuation of its main switch, said tacker comprising a staple magazine mounted on the tacker housing and movable between a blocking position in which its output end for the staples is pivoted downwardly in relation to said tacker housing and an operating position in which its output end is pivoted into a position adjacent to said tacker housing, a coupling element located between said staple magazine and an actuator element for said main switch, said coupling element on the one hand being connected with said tacker magazine and on the other hand being provided with an engagement portion which is in engagement with said actuator element in the on position of said actuator element so that said tacker magazine is held in its operating position by means of said coupling element, and a staple blocking means which blocks feeding of the front staple in said staple magazine in the operating position of said staple magazine and which permits feeding of such front staple into the staple output channel in the blocking position of said staple magazine.
It should be noted, in this respect, that the term "staple" has been used only to simplify the description, but that this term refers to all fastening elements which can be conventionally driven into a workpiece by means of a tacker of this type, that is to say, for example U-shaped staples, nails, pins etc.
When the actuator element is held actuated, the staple magazine is held in its operating position by the coupling element, so that if the tacker is lifted off from the workpiece, the staple magazine will be held in its operating position by means of the actuator element. Since, in the operating position of the staple magazine with the actuator element actuated, the staple blocking means prevents staples from being conveyed out of the staple magazine into the staple output channel, the lifted-off tacker can, therefore, be replaced on a staple not completely driven in, since the staple blocking means prevents a new staple from entering the staple output channel. When the actuator element is released after the tacker has been replaced, so that the actuator element comes into its initial position to actuate the main switch again, the staple blocking means prevents a further staple from being fed into the staple output channel, since, as a result of the operating position of the staple magazine, it is held in its position blocking the supply of staples to the staple output channel.
If the tacker is lifted off from the workpiece and the actuator element is released, the staple magazine pivots into its blocking position in the usual way. The staple blocking means is inactivated and the next staple is therefore, conveyed out of the staple magazine into the staple output channel. This staple can then be driven into the workpiece in the usual way when the tacker is placed on a workpiece.
The staple blocking means may comprise a two-armed pivotably mounted lever which preferably has angled ends. One end of these ends engages with the staple magazine in the operating position of the latter, this so pivoting the lever that the other end is moved into blocking engagement with the front staple in the staple magazine. A pad element having a high coefficient of friction, for engagement with the staple to be blocked, is preferably mounted on the said other end of the lever. This staple blocking means is of simple construction and, simply as a result of the pivoting of the staple magazine into the operating position and the consequent engagement of the staple magazine with one arm of the lever, is brought into a position in which the other arm of the lever blocks the staple feed.
In a preferred embodiment of the invention, the coupling element consists of a bar element having an annular shoulder forming the engagement portion, and the actuator element has a projection which is located between the staple magazine and the annular shoulder and which can be engaged with the latter. Consequently, when the actuator element is actuated, its projection engages with the annular shoulder of the coupling element.
This bar element can have, at its end facing away from the staple magazine, an elastically movable blocking projection which, in the blocking position of the staple magazine, rests against a stationary stop surface so as to block the actuator element. In the operating position of the staple magazine, the blocking projection is flexed or pivoted out of the region of the stop surface.
Other objects, features and advantages of the present invention will become more fully apparent from the following detailed description of the preferred embodiment, the appended claims and the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
In the accompanying drawings:
FIG. 1 shows diagrammatically a vertical section through a power driven tacker embodying the invention; and
FIG. 2 shows a portion of a section, similar to FIG. 1, of a modified staple blocking means according to the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The electro-magnetic tacker illustrated in FIG. 1 has a conventional housing consisting of two half-shells, one of which is removed, so that the other half-shell 1 and the components which it receives can be seen.
The half-shell 1 contains a main switch 3 which is accommodated in a housing and to which a voltage supply cable 2 is connected, and control electronics 5 indicated only diagrammatically and controlled by means of a manually rotatable knob 6. A switch actuator element 4 extends into a hand-gripping orifice 7 of the housing and is coupled mechanically to the switch 3, as indicated at 3'.
Mounted on a pivot axle 9 in the lower part of the housing 1 is a staple magazine 8 of conventional design. At the end of the magazine 8 on the right in FIG. 1, a vertical slot 12 is provided through which extends a pin 11 retained in the housing. This enables the magazine 8 to pivot to a limited extent about the axle 9, specifically between the operating position shown in FIG. 1, in which the pin 11 rests against the lower limiting wall of the slot 12, and a blocking position in which the pin 11 contacts the upper limiting wall of the slot 12. The staple magazine forms, with its end on the right in FIG. 1 and with further parts provided in the housing, a staple output channel 30, into the top end of which extends a driving element 15. The driving element 15 is fastened to the armature 13 of a solenoid which interacts with an annular exciting coil 13' and which, in the non-excited state of the coil, is held by a barrel-shaped spring 14 in the raised position shown. The coil 13' is connected to the switch 3 by leads 13".
A two-armed bell crank lever 16, the ends of the two arms 18 and 19 of which are angled downwardly, is located adjacent the front end region of the staple magazine 8, and is pivoted on axle 17 mounted in the housing just above the front end of the staple magazine 8. A pad element 18' consisting of a material having a relatively high coefficient of friction, for example a plastic, is mounted on the free, downwardly directed end of the arm 18. In the operating position of the staple magazine 8, as illustrated, the free end of the arm 19 of the lever 16 is in contact with the upper surface of the staple magazine 8, with the result that the lever 16 is pivoted into a position in which the pad element 18' is pressed onto the leading staple (not shown) located in the staple magazine 8 and adjacent to the staple output channel 30, so that this staple cannot enter the staple output channel 30. However, if the staple magazine 8 is pivoted downwardly into the above-described blocking position, the arm 19 is released from the top of the staple magazine 8, and the pad element 18' is no longer pressed into engagement with the leading staple, so that the latter can be moved in the conventional way into the staple output channel 30 as a result of spring pressure.
A projection 22 having an orifice is mounted on the topside of the staple magazine 8. A rod element 20 is fastened by means of its lower end in this orifice. For this purpose, the lower end of the rod element has an axially extending open recess and barb-like protrusions 21 which, when the lower end of the rod element 20 is inserted into the orifice in the projection 22 from above, are compressed as a result of elastic deformation and then engage behind the peripheral wall of the orifice. The lower part of the rod element 20 is surrounded by a compression spring 23 which is supported by its lower end seating on the projection 22, and by its upper end engaging under a stationary annular shoulder 24 formed in the housing. Thus, because it engages the stationary annular shoulder 24, the spring 23 exerts on the staple magazine 8 a force acting downwards, that is to say in the direction of displacement into the blocking position.
As indicated in FIG. 1, above the annular shoulder 24, the rod element 20 is guided so as to be axially displaceable in the housing and extends through a projection 25 formed on the actuator element 4. Above this projection 25, an annular rib 26 is formed on the rod element 20. The upper end of the rod element is V-shaped, and on the free leg thereof is disposed a blocking projection 27 with an oblique face 28 which, in the position shown, rests against a side face of a protrusion 29 formed in the housing. This protrusion has a lower stop surface 29' which is directed downwards, and which is located opposite an upwardly facing step 4' of the actuator element 4. The free leg of the bar element 20 having the block-projection 27 is elastically deformable. Thus, when the bar element 20 is lowered from the position shown, that is to say when the staple magazine 8 is moved into the blocking position, the blocking projection 27 moves downwardly between the stop surface 29' of the protrusion 29 and the step 4' of the actuator element 4. In this position, the blocking projection 27 prevents an upward movement of the actuator element 4, and consequently prevents actuation of the main switch 3.
To drive a staple into a workpiece with this tacker, the output end of the staple output channel 30 is placed on a workpiece. Then the tacker is pressed downwards in such a way that the staple magazine 8 is pivoted about the axle 9, against the effect of the spring 23, out of the blocking position into the operating position shown. As a result of contact between the lower end face of the bar element 20 and the upper face of the staple magazine 8, the bar element 20 is also thereby moved upwards. This causes, on the one hand, the spring 23 to be compressed and, on the other hand, the blocking projection 27, because of its upper bevelled surface, to be pivoted out of the region between the step 4' of the actuator element 4 and the stop surface 29' of the protrusion into the position shown. Thus, in the position illustrated, the actuator element 4 can be moved upwards and the coil 13' of the solenoid thereby excited by operation of the switch 3, so that the armature 13 is driven downwards and the driving element 15 drives the staple located in the staple output channel 30 into the workpiece.
An already described above, in this operating position of the magazine 8, the pad element 18' mounted on the lever 16 is engaged with the leading staple located in the staple magazine 8 and prevents it from entering the staple output channel 30. It is, therefore, possible to actuate the actuator element 4 several times and thus carry out further driving strokes on a staple already driven into the workpiece.
If a check is to be made to see whether the staple has been driven far enough into the workpiece, the actuator element 4 is retained in the raised position (i.e. depressed). In this position, the upper surface of the projection 25 of the actuator element 4 is engaged with the lower annular surface of the annular rib 26 of the rod element 20. Thus, when the tacker is lifted off from the workpiece with the actuator element raised, because of this engagement, the rod element 20 is held in the raised position shown. Thus, the staple magazine 8 also remains in its upper operating position, and the pad element 18' prevents further staple feed from the staple magazine 8. It is, therefore, possible in this state to reposition the tacker onto a staple which has not yet been driven in completely. When so replaced, the staple magazine 8 continues to be held in its upper operating position so preventing the leading staple therein from being urged into the staple output channel 30 when the actuator element 4 is released and then returned to the depressed position shown. The actuator element 4 can then be re-actuated to trigger a predetermined number of strokes, for example a single stroke, so that the driver 15 carries out a further driving stroke on the staple already partially driven in.
If the tacker is lifted off from the workpiece without the actuator element 4 being held in a raised position, the staple magazine 8 moves into the blocking position. This being due, on the one hand, because of gravity and, on the other hand, as a result of the effect of the spring 23. The rod element 20 is also moved downwards, and the blocking projection 27 passes into the space between the step 4' of the actuator element 4 and the stop surface 29' of the protrusion 29. Because of the pivoting of the staple magazine 8 into the lower blocking position, the free end of the arm 19 of the bell crank lever 16 is released from the upper surface of the staple magazine 8; thus the pad element 18' is no longer firmly engaged with the front staple in the staple magazine 8. This front staple is, therefore, conveyed into the staple output channel 30, and the tacker is ready to drive in a further staple.
FIG. 2 illustrates a staple blocking means modified in relation to the bell crank lever staple blocking arrangement of the embodiment of FIG. 1. However, the remaining details of the tacker containing the modified staple blocking means of FIG. 2 corresponds to the design of the tacker in FIG. 1.
The staple blocking means of FIG. 2 comprises a leaf spring 116 which is fastened by means of an upturned end region 119 inserted between two ribs 117, 117' formed in the housing half-shell 1. The central region of the leaf spring 116 is angled in relation to the end region 119 and, in the operating position of the staple magazine 8, extends essentially parallel to the longitudinal extension of the latter. The free end 118 of the leaf spring 116 is angled downwardly in the direction of the staple magazine 8, and carries at its extreme free end a pad element 118' corresponding to the pad element 18' of FIG. 1.
In the operating position of the magazine 8, as illustrated in FIG. 2, the pad element 118' is engaged with the staple (not shown) located in the staple magazine 8 and adjacent to the staple output channel 30, and is pressed against this staple as a result of elastic deformation of the leaf spring 116. Especially as a result of elastic deformation of the leaf-spring portion located between the vertical end regions 119 and 118, this leading staple is prevented from entering the staple output channel 30. If the staple magazine 8 is pivoted into the lower blocking position explained in connection with FIG. 1, the free end 118 of the leaf spring 116 is released from the front staple, and the leaf spring can flex back into its relaxed position. In this relaxed position of the leaf spring 116, the free end 118 moves further down than the position in FIG. 2. However, in this relaxed position, the pad element 118' is no longer in blocking engagement with the front staple in the staple magazine, so that this staple can be moved in the conventional way into the staple output channel 30 as a result of spring pressure. It is immediately clear that the next upward pivoting of the staple magazine 8 into its operating position again results in an engagement of the pad element 118' and the front staple located in the staple magazine, so that the free end 118 of the leaf spring 116 is again pivoted under elastic deformation into the position shown in FIG. 2 and prevents this leading staple from being fed into the staple output channel 30 (which in any case now has a staple therein).
The above described embodiments, of course, are not to be construed as limiting the breadth of the present invention. Modifications, and other alternative constructions, will be apparent which are within the spirit and scope of the invention as defined in the appended claims. | An electro-magnetic tacker, which can carry out a limited number of driving strokes when its main switch is actuated, has a staple magazine pivotal between a blocking position and an operating position. In the operating position of the staple magazine, a staple blocking member blocks the front staple located in the staple magazine and, in the blocking position of the staple magazine, releases this staple for entry into a staple output channel. A coupling element connected to the staple magazine has an engagement portion which, in the switched-on position of an actuator element of the main switch, is in engagement with this. In this switched-on position, the actuator element holds the staple magazine in the operating position via the coupling element, so that the tacker can be lifted off from a workpiece, while at the same time the operating position of the staple magazine and the blocking action of the staple blocking member are maintained. | 1 |
FIELD OF THE INVENTION
[0001] The present invention relates to attenuated strains of prokaryotic microorganisms, in particular Salmonella, transformed with nucleic acid encoding papillomavirus virus proteins, to compositions comprising these microorganisms, especially for use as vaccines, and to the medical uses of these strains. In a further aspect, the present invention provides a method of producing assembled papillomavirus virus like particles (VLPs).
BACKGROUND OF THE INVENTION
[0002] Human papilloma virus (HPV) 16 is the major type of HPV which, in association with cofactors, can lead to cervical cancer (49). Studies on HPV have been hampered by the inability to propagate the virus in culture, the lack of animal models and the paucity of virions in clinical lesions. This has led to the development of alternative approaches of antigen production for immunological studies. The conformational dependency of neutralizing epitopes, as observed in experimental animal papillomavirus systems (8, 22) suggests that properly assembled HPV particles are critical for the induction and detection of clinically relevant immune reactivity.
[0003] The HPV capsids are formed by 72 pentameric capsomers of L1 proteins arranged on a T7 icosahedral lattice (15). Recently, a number of investigators have demonstrated the production of HPV capsids, i.e. virus like particles (VLP), by utilizing baculovirus, vaccinia virus or yeast expression systems (15, 22, 45, 48, 61). The potential of VLPs as subunit vaccines has been demonstrated using the cottontail rabbit papillomavirus (CRPV) (4), the canine oral papillomavirus (COPV) (57), and the HPV11 models (45).
[0004] HPV16 infects through the genital mucosa, where benign proliferative lesions are confined. Protection against infection with such a pathogen could be provided by specific (anti-VLP) secretory immunoglobulins A (sIgA) or immunoglobulins G (IgG) in genital secretions. By analogy with existing animal models. HPV16 VLPs-specific antibodies in cervical secretions might help to prevent sexually transmitted infection by HPV16 in women. However, this cannot be formally proven in the absence of an experimental model for genital PV infection and other scenarios requiring cell-mediated immunity cannot be excluded.
[0005] Moreover, the mechanism underlying HPV infection is unclear. HPV may directly infect the basal cells of the stratified cervical epithelium at the occurrence of breaches. Alternatively, HPV infection could also occur either directly through Langerhans cells in intact epithelia or indirectly from an HPV-producing keratinocyte, and thus neutralizing antibodies will not be functional as shown for other viruses. This further adds to the difficulty in providing vaccines effective against HPV infection.
[0006] Immunosuppressed individuals are more prone to develop cervical carcinoma as compared to immunocompetent individuals, suggesting the possibility of using immunotherapy. Therapeutic vaccines (37) aimed to the treatment of established HPV infection or HPV associated premalignant and malignant lesions have been investigated during the last ten years (59). Evidence for HPV-antigen-directed immunotherapy against cervical cancer comes from the observations that experimental (13), (34), (83) and natural (82) PV-associated tumours can be controlled by immunization with E6 and E7 preparations. These studies suggested that CTL might be the most effective immunological effector mechanisms. E6 and E7 preparations consisted in either peptides (13), bacterially prepared fusion proteins (82), eukaryotic transfected cells (83) or recombinant vaccinia viruses (34).
[0007] Recently, chimeric VLPs carrying the 17 kD E7 protein as a fusion with L2 have been shown to induce rejection of syngeneic tumour cells (84) engineered to express L1 and/or E7 ORF (i.e. C3 cells (13) and TCl cells (85)). This data demonstrates the possibility of providing prophylactic and therapeutic effects in the same vaccine preparation. Salmonella that are attenuated, yet invasive, have been proposed for the delivery of heterologous antigens to the mucosal and systemic immune systems (10). The antigen is delivered by the live Salmonella to mucosal inductive sites, where after priming, antigen-specific B and T cells migrate from the site of induction and mature into effector cells. The migrating IgA-expressing B cells home to different mucosal sites, including the genital tract, where they differentiate into IgA secreting plasma cells (32). Thus, oral or nasal immunization can provide protective antibodies in genital secretions. Recently, we and others have shown that mucosal immunization with recombinant Salmonella can elicit antibody responses in the genital mucosa of mice and humans (18, 37, 56).
SUMMARY OF THE INVENTION
[0008] In order to develop a prophylactic vaccine against HPV, we have expressed the major protein L1 of HPV16 in a PhoP c (35) attenuated strain of Salmonella typhimurium. Surprisingly, the inventors found for the first time that it is possible to assemble VLPs in a prokaryotic organism and that nasal immunization of mice with an HPV16-L1/Salmonella recombinant strain induces HPV16-specific conformationally dependent and neutralizing antibodies in serum and genital secretions. The experiments described herein also show that it is possible to assemble chimeric VLPs of a HPV protein and a fusion partner.
[0009] Accordingly, in a first aspect the present invention provides an attenuated strain of a prokaryotic microorganism transformed with nucleic acid encoding papillomavirus virus major capsid protein wherein the protein assembles in the microorganism to form virus like particles (VLPs).
[0010] Thus, the present invention provides a way of producing properly assembled papillomavirus VLPs in an attenuated strain of a prokaryotic microorganism such as Salmonella so that they can be used as a vaccine to raise an immune response in a subject. Preferably, the VLPs are delivered to mucosal sites, having the advantage of generating the immune response to the papillomavirus VLPs at the locations where infection actually takes place, as well as at other mucosal surfaces.
[0011] The term “papillomavirus” used herein covers both human and animal PVs. However, preferably, the papillomavirus is a human papillomavirus (HPV). About 70 different types of HPV have been cloned and characterized (denoted HPV1 to HPV70 . . . ), and all have an 8 kb double stranded Gnome which encodes different early products and two late products L1 and L2, and are either epitheliotropic or mucosatropic. L1 is a major capsid protein and is relatively well conserved among the different HPV types. For a review of the HPV types and their nucleic and amino acid sequences, see Human Papillomaviruses “A Compilation and Analysis of Nucleic Acid and Amino Acid Sequences”, 1994, ed. Myers et al, Theoretical and Biophysics Group T-10 Los Alamos National Laboratory. Clinically, the most important HPV types are those that infect the anogenital tract, and that have high oncogenic risk and a high prevalence. This group includes HPV16, 18, 31, 45 and 56, with HPV16 alone accounting for more than 50% of invasive cancer in the anogenital tract, as well as being the most prevalent single type of HPV.
[0012] The papillomavirus proteins correspond to wild type major capsid proteins (e.g. L1 and/or L2) or may be chimeras of ail or part of a HPV protein and a fusion partner. The fusion partner may be any immunogenic protein against which specific CTL would be targeted. This protein may be an HPV protein (e.g. E7, E6 or E2 of any HPV type), a protein from another pathogen or any tumour specific antigen. In one embodiment the HPV protein is L1 protein coexpressed with L2, with the fusion partner expressed so that it is linked to the L2 protein.
[0013] It has been shown that chimeric VLPs can elicit anti-tumour immunity against carrier and inserted proteins in HPV16 tumour models. Thus, chimeric VLPs which induce E7-specific CTLs aimed to the killing of already HPV infected cells or HPV-associated premalignant lesions. In this event, induction of CTLs to eliminate already HPV infected cells appears therefore an appealing complement to the induction of neutralizing antibodies, and chimeric VLPs have been shown to induce both functions.
[0014] Thus, in one embodiment of the invention, Salmonella strains able to induce neutralizing antibodies and CTLs by expressing chimeric VLPs could be therapeutic at least for early or premalignant HPV lesions in which the downregulation of MHC I or other factors observed in more advanced cancers has not yet occurred.
[0015] Preferably, the prokaryotic microorganism is an attenuated strain of Salmonella. However, alternatively other prokaryotic microorganisms such as attenuated strains of Escherichia coli, Shigella, Yersinia, Lactobacillus, Mycobacteria, Listeria or Vibrio could be used. Examples of suitable strains of microorganisms include Salmonella typhimurium, Salmonella typhi, Salmonella dublin, Salmonella entereuidis, Escherchia coli, Shigella flexeneri, Shigella sonnei, Vibrio cholera, and Mycobacterium bovis (BC6).
[0016] Attenuated Salmonella strains are one of the best characterized mucosal vaccine carriers. Recombinant Salmonella strains that are attenuated yet invasive have been used as oral vaccine vectors to carry protective epitopes of several pathogens into the mucosal associated lymphoid tissue thus inducing mucosal, systemic and CTL immune responses against both the carrier and the foreign antigens (58, 65, 67, 69, 75, 77).
[0017] The currently licensed oral vaccine against typhoid fever S. typhi Ty21a (72) administered as a three-dose regimen of enteric-coated capsules (10 9 CFU/capsule) provided a 67% efficacy over a 3 year period. However, because the S. typhi Ty21a requires high and multiples doses in liquid formulation for higher efficacy, and its mutations are not yet all characterised (63, 64, 70, 71, 78), new attenuated Salmonella strains have recently been developed and tested in humans. These include nutritional auxotrophs in which pathways for biosynthesis of aromatic compounds have been interrupted (Δaro mutants). The ΔaroA, ΔpurA mutants of S. typhi have been tested in human volunteers (32) and were shown to elicit specific cell-mediated immune responses but weak humoral responses. Other aro mutants (aroC and aroD) were insufficiently attenuated and caused fever and bacteremia (79). A double mutant ΔaroC ΔaroD Ty2 (CD 908) was safe and elicited IgG antibodies against LPS in 80% of the immunized adult volunteers (73, 80). S. typhi mutants were also generated in which the adenylate cyclase (cya) and the cAMP receptor (crp) genes were deleted. These gene products are required for the transcription of many genes and operons that control transport processes, expression of fimbriae, flagella and some outer membrane proteins. One mutant χ 3927 (Δcya Δcrp Ty2) was tested and shown to be immunogenic but some volunteers developed fever and vaccine bacteremia (79). Therefore, a novel strain, χ 4073, was constructed by deleting a third gene (cdt) responsible for colonization of deep tissue (66, 68, 74). This strain was administered to volunteers and proved to be completely safe at doses up to 5×10 8 CFU and generated a seroconversion in 80% of the volunteers (66).
[0018] Preferred attenuated Salmonella strains include mutants in a two-component regulatory system, the PhoP/PhoQ genes. These genes affect expression of a number of other genes and are responsive to phosphate levels and to environmental conditions expected to be experienced by Salmonella residing within macrophages. Preferred example of these mutants are the PhoP c strains used in the examples described below. Recently, a PhoP/PhoQ-deleted Salmonella typhi (ty800) has been shown to be safe and immunogenic in humans (81).
[0019] A still more preferred example of such a mutant is one in which a β-aspartate semialdehyde dehydrogenase (asd) vector is incorporated in order to maintain selective pressure in vivo to maintain the expression of HPV16 VLPs. This is surprising as it has previously been reported that such mutant, when administered nasally at least, induces much lower levels of anti-HPV16 L1 VLPs than intact PhoP c strains (see Benyacoub et al, 16 th International Papilloma Conference, Siena, Sep. 5-12, 1997), surviving to a lesser extent and with absence of L1 expression.
[0020] More preferred is use of a PhoP c Δasd strain that places Δasd and the HPV VLP protein or its fusion together in a plasmid that has a ‘medium copy’ number eg. 15 to 20 rather than a higher copy number. Eg. having a pBR ori such as plasmid pYA3342.
[0021] As mentioned above, the attenuated strain of the prokaryotic microorganism is transformed with a nucleic acid encoding one or more major papillomavirus capsid proteins. The inventors found for the first time that, when this nucleic acid is expressed in the microorganisms, the capsid proteins produced assemble correctly to form VLPs, making them especially suitable for the vaccination of subjects against papillomaviruses. Preferably, the major viral capsid protein is L1, optionally additionally including nucleic acid encoding L2 protein. As discussed above, the capsid protein may be linked to a fusion partner such as another antigen.
[0022] In a further aspect, the present invention provides a composition comprising one or more of above attenuated prokaryotic microorganisms, optionally in combination with a physiologically acceptable carrier. Preferably, the composition is a vaccine, especially a vaccine for mucosal immunization, e.g. for administration via the oral, rectal, nasal, vaginal or genital routes. Our earlier studies using recombinant Salmonella expressing hepatitis B virus antigen (18) showed that vaccination via any of these routes produces a sIgA response in the mucosal secretions at other sites. Advantageously, for prophylactic vaccination, the compositions comprises one or more strains of Salmonella expressing a plurality of different VLPs, e.g. VLPs from different papillomavirus types. This has the advantage of improving the protective effect of the vaccine to a range of challenges by the different papillomavirus types. For therapeutic vaccination, subsequent chimeric VLP constructs can comprise fusion products of various HPV type L1 capsids with the same L2 fusion partner.
[0023] In a further aspect, the present invention provides an attenuated strain of a prokaryotic microorganism described above for use as a medicament, especially as a vaccine.
[0024] In a further aspect the present invention provides the use of an attenuated strain of a prokaryotic microorganism transformed with nucleic acid encoding papillomavirus virus major capsid protein, wherein the protein assembles in the microorganism to form virus like particles, in the preparation of a medicament for the prophylactic or therapeutic treatment of papillomavirus infection or anogenital cancer, especially cervical cancer.
[0025] Generally, the microorganisms or VLPs according to the present invention are provided in an isolated and/or purified form, i.e. substantially pure. This may include being in a composition where it represents at least about 90% active ingredient, more preferably at least about 95%, more preferably at least about 98%. Such a composition may, however, include inert carrier materials or other pharmaceutically and physiologicaly acceptable excipients. A composition according to the present invention may include in addition to the microorganisms or VLPs as disclosed, one or more other active ingredients for therapeutic use, such as an antitumour agent.
[0026] The compositions of the present invention are preferably given to an individual in a “prophylactically effective amount” or a “therapeutically effective amount” (as the case may be, although prophylaxis may be considered therapy), this being sufficient to show benefit to the individual. The actual amount administered, and rate and time-course of administration, will depend on the nature and severity of what is being treated. Prescription of treatment, eg. decisions on dosage etc, is within the responsibility of general practioners and other medical doctors.
[0027] A composition may be administered alone or in combination with other treatments, either simultaneously or sequentially dependent upon the condition to be treated.
[0028] Pharmaceutical compositions according to the present invention, and for use in accordance with the present invention, may include, in addition to active ingredient, a pharmaceutically acceptable excipient, carrier, buffer, stabiliser or other materials well known to those skilled in the art. Such materials should be nontoxic and should not interfere with the efficacy of the active ingredient. The precise nature of the carrier or other material will depend on the route of administration.
[0029] Examples of techniques and protocols mentioned above can be found in Remington's Pharmaceutical Sciences, 16th edition, Osol, A. (ed), 1980.
[0030] In a further aspect, the present invention provides a method for producing assembled papillomavirus virus like particles comprising culturing an attenuated strain of a prokaryotic microorganism transformed with nucleic acid encoding papillomavirus virus major capsid protein wherein the protein is expressed and assembles in the microorganism to form virus like particles. Preferably, the method additionally comprises the step of recovering the VLPs from the prokaryotic microorganism.
[0031] In a further aspect, the present invention provides the use of a papillomavirus VLP as obtainable by transforming an attenuated prokaryotic microorganism with nucleic acid encoding the VLPs and expressing the nucleic acid to produce assembled VLPs, in a diagnostic method. in one embodiment, present invention provides a method for detecting the presence of anti-papillomavirus antibodies in a sample from a subject comprising immobilizing the HPV VLPs on a solid support, exposing the support to the sample and detecting the presence of the antibodies, e.g. using ELISA.
[0032] Preferred embodiments of the present invention will now be described by way of example and not limitation with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE FIGURES
[0033] [0033]FIG. 1. HPV16 L1 expression in the PhoP c /HPV strain. Salmonella were grown overnight and prepared as indicated in Material and Methods. A. Commassie blue staining of a 10%SDS PAGE gel; Lane M : Molecular weight marker; Lane 1: total lysate of the PhoP c strain Lane 2: total lysate of the PhoP c /HPV strain, a unique 57 kDa protein is indicated with an arrow. B. Immunoblot using anti-HPV16-L1 mAb of the total and fractionated PhoP c /HPV lysate. Lane tot: total lysate, Lane 1 to 25: different fractions obtained after fractionation of the PhoP c /HPV lysate through a 10-40% sucrose gradient, the heavier fraction of the gradient being in lane 1. The 57 kDa protein band identified as being L1 is indicated (arrow).
[0034] [0034]FIG. 2. HPV16 L1 assemble into VLPs. Electron micrographs of (A) PhoP c /HPV16 VLPs and (B) Baculo-derived HPV16 VLPs. In A, factions 7 to 13 of PhoP c /HPV lysate (FIG. 1) were pooled. The samples were negatively stained with phosphotungstic acid. Bar represents 53 nm.
[0035] [0035]FIG. 3. Anti-HPV16VLP and anti-LPS systemic and mucosal antibody responses after nasal immunization with the PhoP c /HPV strain. Three 6-week-old BALB/c female mice were immunized with 5×10 7 CFU, sampled at the indicated weeks, sacrificed and bled at week 27. Data are expressed as the geometric means of the reciprocal dilutions of specific IgG in serum and specific IgA per microgram of total IgA or IgG per microgram of total IgG in secretions. Error bars indicate the standard errors of the means.
[0036] [0036]FIG. 4. HPV viral cycle and vaccination strategies. In the left portion of the figure the HPV productive viral cycle during keratinocyte differentiation is schematically drawn (early infection-CIN I). A late stage of infection (CIN III-tumour) in which the HPV DNA is integrated into the host genome is shown on the right. Different protective immune mechanisms are shown with arrows indicating the sites of action. Antibody-dependent cellular cytotoxicity (ADCC) mechanims which require viral antigens to be expressed at the surface of cells are not indicated.
[0037] [0037]FIG. 5. In vitro neutralization of HPV16 pseudotype virus infection of mouse C127 cells. (A) no virus added. (B-H) Equal aliquots of an HPV16(HPV1) pseudotype virus containing extract was added. The aliquots were preincubated with (B) no antibodies, (C) BPV1 neutralizing MoAb B1.A1, (D) HPV16(BPV1) neutralizing MoAb H16.E70, (E) mouse preimmune sera, (F) mouse#4 immune sera (week27) , (G) mouse#5 immune sera (week27) , (H) mouse#4 immune sera (week27) .
[0038] [0038]FIG. 6 shows the results of tumour growth experiments in mice immunized with Salmonella HPV producing strains. Nasal immunisations were performed three times weekly with either 20 μl PBS (A) or 5 μg of purified HPV16 VLPs+5 μg of cholera toxin (CT)(E) and two times at week0 and week2 with 10 CFU of PhoPc/HPV16 L1 (b), χ 4550/pYA34L1 (C) and χ 4550/pYA32L1 (D). All mice were challenged with 5 105 C3 cells into the flank two weeks after the last immunisation. The mean volume of the tumours in each group are shown, while the number of mice harbouring a tumour/number of mice injected is indicated at Day 17.
[0039] [0039]FIG. 7 shows coexpression of L1 and L2 in PhoP c /HPV16 L1-L2. Blot A was revealed with an anti-L2 antibody, while blot B was revealed with anti-L1 antibody (Camvir).
[0040] [0040]FIG. 8 shows the expression of L1 in E. coli BL12 pET 3DL1. Identical amounts of bacteria were loaded (3×10 6 CFU) after 3 hours incubation with IPTG and the blot was revealed with an anti-L1 antibody.
[0041] [0041]FIG. 9 shows the results of tumour growth experiments with PhoP c Δasd mutants having or lacking the ability to express L1 VLPs. Plots are for PBS (A), PhoP c Δasd/nasal (B) and PhoP c Δasd/HPVL1 nasal (C).
[0042] [0042]FIG. 10 is a map showing the essential characteristics of plasmid pYA3342
DETAILED DESCRIPTION
Materials and Methods
[0043] Plasmid construction and bacterial strains used
[0044] Plasmid pFS14nsd HPV16-L1 was constructed by exchanging in the plasmid pFS14 NSD (54) the hepatitis B nucleocapsid gene (HBcAg, NcoI-HindIII fragment) for a NcoI-HindIII fragment encoding the HPV16-L1 open reading frame. The HPV16-L1 NcoI-HindIII fragment was generated by Polymerase Chain Reaction (PCR) using the baculovirus expression plasmid pSynwtVIHPV16 114/B-L1+L2 (23) as a template with a 28 mer containing a NcoI site: 5′-GGGCCATGGCTCTTTGGCTGCCTTAGTGA-3′ and a 27 mer containing a HindIII site 5′-GGGAAGCTTCAATACTTAAGCTTACG-3′. The final construct containing the Tac promoter places the HPV16-L1 ATG at position +8 relative to the Shine-Dalgarno sequence and introduces a change in the second amino acid which becomes an alanine instead of the serine encoded by the original sequence. Sequencing of the entire L1 open reading frame was carried out (MycrosynthAG) and no further nucleotide change was observed Plasmid pFS14nsd HPV16-L1 was amplified in E. coli JM105 and then electroporated as described previously (50) into bacterial strain CS022. This strain is derived from the ATCC 14028 strain, into which the pho-24 mutation was introduced by P22 transduction, resulting in attenuation in both virulence and survival within macrophages in vitro (PhoP c , (35)). The resultant recombinant strain is called PhoP c /HPV hereafter.
[0045] Expression of HPV16-L1 in Salmonella and VLPs purification
[0046] After overnight growth at 37° C. the recombinant bacteria were lysed by boiling in Laemmli buffer containing 5% SDS. The lysates were separated on 10% SDS/PAGE gels and expression of L1 was analyzed by Western blot using HPV16-L1 mAb CAMVIR-1 (33) as primary antibody, an alkaline-phosphatase conjugated goat anti-mouse IgG (Sigma) as secondary antibody and BCIP/NBT (Boehringer) as substrate.
[0047] To prepare VLPs, bacteria were lysed by sonication and the lysate fractionated on a 10%-40% sucrose gradient in Phosphate Buffer Saline (PBS) containing 1M NaCl for 1 hour at 40 Krpm using a TST41.14 rotor. Fractions of the gradient were then analysed for the presence of the L1 protein by Western blot. The fractions of high sedimentation containing the L1 protein were pooled, dialyzed against PBS/O.5M NaCl. VLPs were pelleted for 1 h at 50 Krpm using a TST65.1 rotor, adsorbed to carbon-coated grids, negatively stained with phosphotungstic acid and examined with a Philips electron microscope.
[0048] Purification of HPV16 VLPs expressed in insect cells from a recombinant baculovirus
[0049] The transfer vector pSynwtVI-HPV16 114/B-L1+L2 (23) was cotransfected with the linearized genome of baculovirus (Baculo-Gold, Pharmingen) using the calcium-phosphate method into SF9 cells. The recombinant baculoviruses were plaque-purified and propagated by standard methods (39). Baculo-derived HPV16 VLPs were purified as described previously (23).
[0050] Immunization and sampling of mice
[0051] Six-week-old female BALB/c mice were immunized at day 0 and at week 14 by the nasal route with 5×10 7 CFU of inoculum. Blood, saliva and genital samples were taken as described previously (18). All samples were stored at 70° C.
[0052] ELISA
[0053] The amount of total IgA, anti-LPS IgA and IgG antibodies in samples were determined by enzyme-linked immunosorbent assay (ELISA) as described previously (18). For the anti-HPV16 VLP, ELISA plates were coated with 10 ng of a preparation of baculo-derived HPV16 VLPs in PBS (total protein content was determined with a BioRad Protein assay with BSA as standard). This amount of VLP was saturating in our ELISA test. Endpoint dilutions of samples were carried out. The specific IgA or IgG amounts are expressed as reciprocal of the highest dilution that yielded an OD 492 four times that of preimmune samples. These reciprocal dilutions were normalized to the amount of total IgA or IgG in saliva and genital washes. ELISA plates were also coated with 10 ng of baculo-derived HPV16 VLPs in 0.2M carbonate buffer pH9.5 to determine the titer of antibodies recognizing unfolded VLPs (14).
[0054] In vitro HPV16 neutralization assay
[0055] Infectious pseudovirions consisting of HPV capsid made of L1 and L2 surrounding the bovine papillomavirus type 1 (BPV1) genome, designated HPV16(BPV1), were generated as recently described (43). Briefly. BPHE-1 hamster cells harbouring autonomously replicating BPV1 genomes were co-infected with defective recombinant Semliki forest viruses that expressed L1 and L2 virion capsid genes of HPV16. Infectious pseudotype HPV16 virus in cell extracts was quantitated by the induction of transformed foci in monolayers of mouse C127 cells. Neutralizing activity was measured after preincubation of the cell extracts with mouse sera diluted 1:50 (1.0 ml final volume) in culture medium. Mouse monoclonal antibodies H16.E70 and B1A1 were generated against recombinant baculovirus expressed HPV16 L1 VLPs and BPV16 VLPs respectively, and used at a 1:100 dilution. HPV16.E70 and B1.A1 served as positive and negative controls for HPV16 (BPV1) neutralization, respectively.
Results
[0056] HPV16-L1 is expressed in PhoP c and VLP assemble
[0057] The open reading frame of the major protein L1 of HPV16 was cloned in the plasmid pFS14 NSD (53). L1 is constitutively expressed under the control of the Tac promoter in S. typhimurium. A unique 57 kDa protein detected in the lysate of PhoP c /HPV overnight cultures (FIG. 1A), was identified as HPV16 L1 by Western immunoblot using an anti-HPV16-L1 monoclonal antibody (CAMVIR, (33), FIG. 1B). To determine whether the L1 protein expressed by PhoP c /HPV assembled into VLP, the bacterial lysate was fractionated through a 10-40 % sucrose gradient and the heavier fractions containing the L1 protein FIG. 1B) were analyzed by electron microscopy. Spherical particles typical of PV capsids were recovered from the bacterial preparation (FIG. 2A) but the bacterial VLPs appeared more polymorphic in size with diameters ranging from 40 to 55 nm (FIG. 2A) when compared to 55 nm VLPs expressed in insect cells (FIG. 2B).
[0058] Nasal immunization with the PhoP c /HPV strain induces systemic and mucosal antibody responses
[0059] Since nasal immunization using recombinant Salmonella was shown to elicit strong vaginal sIgA responses against an expressed foreign antigen (18), we immunized mice nasally with the PhoP c /HPV strain (5×10 7 CFU). Samples of blood, saliva and vaginal washes were taken 0, 2, 4, and 6 weeks after immunization. The immune responses against both the carrier, i.e. anti-LPS and the carried antigen, i.e. anti-HPV16 VLP, were determined Serum HPV16 VLP specific IgG (FIG. 3) were detected after 2 weeks in one mouse and after 4 weeks in all mice. The response peaked after 6 weeks at relatively low titers and persisted at least until week 14. At that time, no HPV16 VLP specific antibodies were detected in vaginal secretions, while one mouse had low titers of IgA in the saliva. The systemic and the mucosal immune responses against LPS were relatively low (FIG. 3), but similar to those elicited by the PhoP c /HBc strain (18) suggesting a normal take of PhoP c /HPV Salmonella by the mice. The low anti-LPS response observed after nasal immunization incited us to perform a booster immunization. Thus, a second nasal immunization was performed at week 14 and samples were taken 5 and 10 weeks later (week 19 and 24 respectively). The second immunization induced, 5 weeks later (week 19), a 15 fold increase of anti-BPV16 VLP IgG in serum, as well as anti-HPV16 VLP IgA in the vaginal washes (FIG. 3) from the three mice. Anti-HPV16 VLP IgG were also found in vaginal washes but only in two mice at week 19 and titers were again almost undetectable at week 24 (FIG. 3). Anti-HPV16 VLP IgA and IgG were also found in the saliva of the three mice in amounts comparable or slightly higher to those found in vaginal washes.
[0060] Anti-HPV16 VLP antibodies recognize only folded VLP
[0061] In order to examine whether the immune responses induced by the PhoP c /HPV strain generated conformational antibodies directed against native but not unfolded VLPs, we measured by ELISA (Table 1) the binding of antibodies, in the samples from the immunized mice, to baculo-derived VLPs in PBS (native form) or in carbonate buffer (pH 9.5, unfolded VLP, (14)). The specific IgG or IgA elicited by the PhoP c /HPV strain very poorly recognizes unfolded VLPs suggesting that the majority of L1 were folded into highly ordered structures when expressed in PhoP c /HPV (Table 1).
[0062] In vitro neutralizing activity of the immune sera
[0063] In previous studies of baculo-derived VLPs, neutralizing activity and protection from experimental infection generally correlated with ELISA reactivity to native VLPs. We therefore wished to determine if the conformationally dependent anti-VLP antibodies elicited by the live Salmonella vaccine were also neutralizing. Although no infectivity assay or source of the virus currently exists for authentic HPV16, it has recently been demonstrated that HPV16 capsid proteins can encapsidate autonomously replicating BPV1 genomes resulting in HPV16(BPV1) pseudotype virions whose infectivity can be monitored by focal transformation of cultured mouse fibroblasts (43). We therefore used the HPV16(BPV1) infectivity assay to examine the neutralizing activity of the mouse sera generated above. Each of the three immune sera displayed strong neutralizing activity against HPV16(BPV1) (FIG. 5), but did not neutralize BPV1 virions (data not shown). The preimmune sera had no neutralizing activity. The neutralizing activities of the immune sera appeared to correlate with the titers in the native VLP ELISA, although the sera were only tested at a single dilution.
[0064] Tumour protection assay in the HPV16 mouse tumour model
[0065] It has been recently shown that the growth syngeneic tumour cells (C3) injected into the flank of C57BL/6 mice was inhibited by a subcutaneous immunization with purified HPV16 cell (84). We have tested whether nasal immunization with purified VLPs and recombinant Salmonella/HPV strains was able to induce the same effect. Specifically, we have tested the following stains: PhoPc/HPV16 L1 (86) and the χ 4550 (56) expressing either high levels ( χ 4550/pYA34L1) or low levels ( χ 4550/pYA32L1) HPV16 L1. Tumour growth in the different groups of mice is shown in FIG. 6. Our preliminary results demonstrate that nasal immunization with purified VLPs is effective and that all the Salmonella/HPV strain tested induced partial tumour protection. Of interest, is the strain χ 4550/pYA34L1 that prevented complete tumour growth in 4/10 mice.
[0066] Coexpression of the L2 protein into PhoPc/HPV16
[0067] The L2 OR17 was cloned downstream of the L1 ORF by PCR into the plasmid pPSnsdHPV16 L1 (86). The PCR reaction included a 5′ specific oligonucleotide that contained a synthetic Shine-Dalgarno sequence in order to allow translation of 12 from a polycistronic L1-L2 RNA. The resultant PhoPC/HPV16 L1+L2 recombinant strain expressed both L1 and L2 and VLPs assembled in amount similar to the parent PhoPC/HPV16 L1 strain as assessed by a sandwich ELISA This suggests that by fusing the E7 ORF to the L2 ORF, in the PhoP c /HPV16 L1+L2 strain, a chimeric VLPs would also assemble and such recombinant Salmonella strain used to induce HPV16 E7-CTLs.
[0068] High level expression of L1 in the inducible E. coli PET expression system
[0069] The L1 ORF was cloned in the plasmid pET3 (ovagen). L1-expression driven by a T7 promoter was assessed in the strain BL21apLysS (expressing T7 polymerase upon IPTG induction). After IPTG induction, a 10 fold higher level of L1 expression/bacteria was achieved in comparison to the Salmonella PhoP c strain (see FIG. 8). The lysate of this recombinant E. coli formed a band at a density of VLPs in a CsCl density gradient, suggesting that the VLPs self-assembled in this bacteria.
[0070] Induction of therapeutic immune response with Δasd mutants
[0071] A deletion in the aspartate-β-semialdehyde dehydrogenase (asd) gene was introduced into the PhoP c strain described above by P22Htint bacteriophage transduction. The original P22Htint lysate propagated on the χ 3520 S. typhimurium Δasd A1 zhf-4::Tn10 (provided by Dr R Curtiss III). A tetracycline sensitive PhoP c Δasd strain was then selected (see Maloy et al (1981) J. Bacteriol p1110-1112 incorporated herein by reference). A NcoI-HindIII fragment containing HPV16 L1 (from the plasmid pFS14nsd HPV16-L1-see Nardellihaefliger et al (1997) Infection & immunity 65 (8) 3328-3336 incorporated herein by reference) was cloned into the NcoI-Hind-III sites of the plasmid pYA3342- (provided by Dr R Curtiss III) and the resultant recombinant PhoP c Δasd/HPV16 L1 strain was used in a tumour protection assay as follows.
[0072] Nasal immunisations were performed at week 0 and week 2 with 10 μl of PBS (A in FIG. 9), with 1×10 7 CFU of recombinant PhoP c Δasd (B in FIG. 9) or 1×10 7 CFU recombinant PhoP c Δasd/HPV16 L1. All mice were challenged with 5×10 5 C3 cells into the flank four weeks after the last immunisation.
[0073] Results, displayed graphically in FIG. 9, show the protection against tumour growth conferred by the immunisation with the PhoP c Δasd/HPV16 L1, No protection was conferred by the parent strain that lacks expression of the L1 antigen PhoP c Δasd.
Discussion
[0074] In this study, we demonstrate that an attenuated Salmonella strain expressing the major capsid protein of HPV16 is a promising vaccine candidate against HPV16 infection, as the VLPs that are assembled by this recombinant bacteria can induce serum as well as genital VLP-specific conformational antibodies. The results above also show that the antibodies are able to neutralize HPV16 viruses. These results could be readily extrapolated by the skilled person to other types of HPV or other papillomaviruses, or other prokaryotic microorganisms.
[0075] The life cycle of papillomavirus is intimately associated with the differentiation of the epithelial cells in skin or the oral and genital mucosa (5, 19, 40, 62). It is believed that viruses gain access to the basal epithelial cells through mucosal abrasions (21). Upon infection of the cervical epithelium for instance, the viral DNA released in the cytoplasm of the basal cells migrates into the nucleus where it remains episomic and early genes are transcribed leading to a low rate of cell proliferation and the thickening of the basal layer (Cervical intraepithelial neoplasia type I, CIN I). As the infected epithelial cells migrate through the suprabasal layer and undergo differentiation, the episomal viral genome replicates reaching ˜1000 copies per cell (29). Concomitant to viral DNA amplification, late genes become expressed and capsids assemble in terminally differentiated keratinocytes (FIG. 4), thus facilitating a new round of infection. In high grade lesions (CIN III and carcinoma) the entire epithelium consists of undifferentiated basal cells in which the viral DNA has been integrated into cellular DNA. In these cells, the E6/E7 gene products constitute the major HPV proteins expressed and viruses are no longer produced.
[0076] Based on our knowledge of HPV pathogenesis, it appears that two arms of immunity (humoral and cellular) have to be effective to prevent viral infection, to decrease the local viral load, or to cure tumors (FIG. 4, see also (59)). A local or systemic humoral immune response with neutralizing antibodies is likely to block early infection, while a cellular response may contribute to the elimination of untransformed or transformed infected cells. An ideal vaccine should trigger the two types of response, although the immunological correlate of protection and of cure have not been identified so far.
[0077] Prophylactic vaccines inducing type-specific neutralizing conformational (anti-VLP) antibodies have been shown to prevent CRPV or COPV infections in cottontail rabbit (4) or dog (57), respectively. In both cases serum neutralizing antibodies where generated by vaccination with self-assembled PV capsids. By analogy, neutralizing antibodies to HPV16 capsid in cervical secretions are expected to prevent infection. Since the precise mucosal site where early HPV infection takes place is not known, it is difficult to predict whether sIgA antibodies acting from the lumenal site or circulating IgG antibodies reaching the basal layers will be most efficient.
[0078] The elimination of HPV-infected cells or tumor cells requires a cellular immune response with cytotoxic T lymphocytes (CTL) recognizing viral antigens presented by MHC class I molecules on the infected cells. Therapeutic vaccines aimed at eliminating HPV-induced tumors have been generated using either peptides corresponding to T cell epitopes from the E6/E7 oncogenes or E6/E7 expressing vaccinia viruses. Both were shown to elicit CTLs and in some cases tumor regression was observed (3, 6, 7, 12, 13, 34). One of the major problems, however, is that MHC class I molecules are down-regulated in the differentiated keratinocytes that produce viruses or in tumour cells (9).
[0079] Since both humoral and cellular immunity are believed to control HPV infection and since local and systemic responses are desirable, an efficient vaccine should reach inductive sites associated with mucosal surface and/or peripheral lymph nodes. Live bacterial vaccines are known to cross mucosal surfaces and elicit humoral or cellular responses (41). Recombinant and attenuated enteropathogenic bacteria, such as Salmonella, represent ideal antigen delivery systems, because they efficiently cross all mucosal surfaces to gain access to both mucosal organized lymphoid tissue (MALT) or draining lymph nodes. They exploit the two basic sampling systems mediating uptake of mucosally administered antigens including M cells in simple epithelia and dendritic cells both in simple and stratified epithelia (38). We have selected a Salmonella typhimurium strain attenuated for macrophage survival, because long lasting antibody responses were elicited by a single nasal, oral, rectal or vaginal administration of recombinant bacteria expressing a foreign antigen (18). In that study, the best genital responses were obtained after nasal immunization. In the airways, antigen uptake occurs through M cells found in NALT, the nasal associated lymphoid tissue (25) and BALT, the bronchial associated lymphoid tissue (55). The primed IgA-expressing lymphocytes then migrate into cervical and uterine tissues where they produce polymeric IgA antibodies, which are transported across the epithelium by the polymeric Ig receptor (26-28). Intraepithelial dendritic cells in the bronchial epithelium also play a major role in antigen presentation by taking up the antigens in the respiratory epithelium and carrying them to distant draining lymph nodes where priming occurs (17). This probably explains why nasal immunization is so efficient in triggering both local and systemic antibody responses.
[0080] Antigens expressed in Salmonella strains can also elicit cellular responses with specific CTLs (1, 16, 58). Depending on which viral antigen is expressed, specific CTLs recognizing infected cells at different stages of differentiation could be generated (FIG. 4). For instance, E7-specific CTLs were generated by immunizing mice with recombinant Salmonella expressing HPV16 E7 epitopes (31).
[0081] To trigger neutralizing antibodies using recombinant Salmonella, it is essential that the antigen retains its native conformation. For HPV, this requires that the L1 proteins form VLPs. Papilloma VLPs haste been shown to assemble in eukaryotic cells (15, 22, 45, 48, 61), but not in prokaryotes. In bacteria mainly L1-fusion proteins were expressed (2, 20, 24) and when bona fide L1 proteins were expressed, VLP assembly was not examined (11). As shown in this paper, HPV16 VLP assemble in Salmonella probably because the level of expression achieved in our experiments was high and capsid assembly does not require glycosylation (60). Capsid production in bacteria has also been reported for other viruses such as the nucleocapsid of Hepatitis B virus (52) and the capsid of Polyomavirus (30, 46). Polyomavirus VP1 major capsid protein, analogous to HPV L1, forms capsomers when expressed in E. coli which subsequently self-assembled into VLPs in vitro (46). The fact that only capsomers but no VLPs were recovered is probably due to the reducing agents present during purification, which are known to disrupt capsids (47).
[0082] Nasal immunization with the PhoP c /HPV strain induced systemic and mucosal antibodies against native but not denatured HPV16 VLPs. In contrast, recombinant vaccinia expressing HPV1 capsid protein triggered serum antibodies recognizing both folded and unfolded VLP, probably reflecting different mode of viral protein expression, and low HPV-specific genital IgA antibody titers (14), as expected with a non-mucosal route of immunization.
[0083] Antibody titers against the foreign antigen induced by PhoP c /HPV compared to PhoP c /HBc Salmonella were about 10 times lower (18). This could reflect differences in immunogenicity between the two viral antigens (51) or, more likely, differences in plasmid stability. In contrast to the HBc DNA, the plasmid carrying the HPV16-L1 DNA was unstable in Salmonella in vivo in the absence of selective pressure, since less than 1% of the Salmonella recovered from different tissues two weeks after immunization still harboured the L1-containing plasmid (data not shown). To increase the stability of the plasmid we are currently recloning the L1 gene in β-aspartate semialdehyde dehydrogenase (asd)based vectors which maintain selective pressure in vivo (36, 56).
[0084] The above work also demonstrates the following points:
[0085] (a) that purified VLPs and Salmonella/HPV strains are capable of providing tumour protection in a HPV16 mouse tumour model.
[0086] (b) that chimeras of a HPV protein and a fusion partner assemble in prokaryotes to form VLPs.
[0087] c) that high levels of expression of HPV proteins that assemble to form VLPs can be obtained in E. coli, demonstrating that the invention is applicable in prokaryotes other than Salmonella.
[0088] In conclusion, we have constructed a recombinant Salmonella strain expressing HPV16-L1 capsid proteins and assembling VLPs that induce conformational serum IgG and vaginal sIgA antibodies recognizing VLPs. Neutralizing activities of these antibodies were tested and shown to display strong neutralizing activity in an HPV16(BPV1) infectivity assay.
TABLE 1 Titers of IgG (in serum) or IgA (in vaginal washes) against native and unfolded HPV16 VLP in mice immunized with PhoP c /HPV anti- Samples anti-HPV16 VLP HPV16 VLP unfolded a IgG titers b #4 serum (week 27) 60,000 100 #5 serum (week 27) 80.000 200 #6 serum (week 27) 20,000 100 Camvir c 16,000 80,000 IgA titers #4 Vaginal Washes (week 19) 40 <1 #5 Vaginal Washes (week 19) 20 <1 #6 Vaginal Washes (week 19) 40 1
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[0173] 84. Greestone et al, 1997. EPV1 6 L1/L2-E7 Chimeric papillomavirus-like particles induce both neutralizing antibodies and E7 specific antitumour immunity. 16th International Papillomavirus Conferencce, Siena, Italy, Abstract: 177.
[0174] 85. Lin et al, 1996. Cancer Research, 56(1):21-26.
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[0178] 89. Nakayama, Kelly and Curtiss (1988) Biotechnol. 6:693-697. | This application relates to the use of attenuated prokaryotic miccrooganism strains (such as Salmonella) expressing nucleic acid encoding HPV proteins as vaccines against HPV infection and the associated increased risk of cancer. In particular, the work shows that it is possible to assemble VLPs in a prokaryotic organism and that nasal immunization of mice with the strains HPV-specific conformationally dependent and neutralizing antibodies in serum and genital secretions. The experiments described herein show that it is also possible to assemble chimeric VLPs of a HPV including a fusion partner and that tumour protection can be induced. | 8 |
[0001] This application is a continuation of and claims the benefit of U.S. utility patent application Ser. No. 10/905,993, filed on Jan. 28, 2005, and entitled “Apparatus and Method for Increasing Well Production Using Surfactant Injection,” which in turn claimed the benefit of U.S. provisional patent application No. 60/617,837, filed on Oct. 12, 2004, and entitled “Apparatus and Method for Increasing Well Production Using Surfactant Injection.” Each of these applications are incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] The present invention relates to gas recovery systems and methods, and in particular to an apparatus and method for increasing the yield of a methane well using direct injection of surfactant at the end of a well bore incorporating a downhole valve arrangement.
[0003] It has long been recognized that coalbeds often contain combustible gaseous hydrocarbons that are trapped within the coal seam. Methane, the major combustible component of natural gas, accounts for roughly 95% of these gaseous hydrocarbons. Coal beds may also contain smaller amounts of higher molecular weight gaseous hydrocarbons, such as ethane and propane. These gases attach to the porous surface of the coal at the molecular level, and are held in place by the hydrostatic pressure exerted by groundwater surrounding the coal bed.
[0004] The methane trapped in a coalbed seam will desorb when the pressure on the coalbed is sufficiently reduced. This occurs, for example, when the groundwater in the area is removed either by mining or drilling. The release of methane during coal mining is a well-known danger in the coal extraction process. Methane is highly flammable and may explode in the presence of a spark or flame. For this reason, much effort has been expended in the past to vent this gas away as a part of a coal mining operation.
[0005] In more recent times, the technology has been developed to recover the methane trapped in coalbeds for use as natural gas fuel. The world's total, extractable coal-bed methane (CBM) reserve is estimated to be about 400 trillion cubic feet. Much of this CBM is trapped in coal beds that are too deep to mine for coal, but are easily reachable with wells using drilling techniques developed for conventional oil and natural gas extraction. Recent spikes in the spot price of natural gas, combined with the positive environmental aspects of the use of natural gas as a fuel source, has hastened development of coal-bed method recovery methods.
[0006] The first research in CBM extraction was performed in the 1970's, exploring the feasibility of recovering methane from coal beds in the Black Warrior Basin of northeast Alabama. CBM has been commercially extracted in the Arkoma Basin (comprising western Arkansas and eastern Oklahoma) since 1988. As of March 2000, the Arkoma Basin contained 377 producing CBM wells, with an average yield of 80,000 cubic feet of methane per day. Today, CBM accounts for about 7% of the total production of natural gas in the United States.
[0007] While some aspects of CBM extraction are common to the more traditional means of extracting oil, natural gas, and other hydrocarbon fuels, some of the problems faced in CBM extraction are unique. One common method generally used to extract hydrocarbon fuels from within minerals is hydraulic fracturing. Using this technique, a fracturing fluid is sent down a well under sufficient pressure to fracture the face of the mineral formation at the end of the well. Fracturing releases the hydrocarbon trapped within, and the hydrocarbon may then be extracted through the well. A proppant, such as course sand or sintered bauxite, is often added to the fracturing fluid to increase its effectiveness. As the pressure on the face of the fractured mineral is released to allow for the extraction of the hydrocarbon fuel, the fracture in the formation would normally close back up. When proppants are added to the fracturing fluid, however, the fracture does not close completely because it is held open by the proppant material. A channel is thus formed through which the trapped hydrocarbons may escape after pressure is released.
[0008] Although course fracturing of this type is very successful in some applications, it has not proven particularly useful in the recovery of CBM. Coal fines recovered with the water and methane during CBM extraction will quickly foul the well when course fracturing techniques are used. This necessitates the frequent stoppage of CBM recovery in order that the production tubing may be swabbed or cleaned. It has been found that course fracturing will significantly reduce both the long-term productivity and ultimate useful life of a CBM well.
[0009] While traditional fracturing has proven unsuccessful in CBM extraction, all coal beds contain cleats, that is, natural fractures through which CBM may escape. As hydrostatic pressure is decreased at the cleat by the removal of groundwater, methane within the coal will naturally desorb and move into the cleat system, where it may flow out of the coal bed. CBM may thus be withdrawn from the coalbed in this manner through the well, without the necessity in many cases of any artificial fracturing methods. CBM exploration and well placement strategies thus are highly dependent upon a good knowledge of cleat placement within the coalbed of interest.
[0010] If artificial fracturing processes are used to stimulate production in CBM wells, they must be very gentle so as not to harm the coalbed cleats, and thereby reduce rather than increase well production. Acids, xylene-toluene, gasoline-benzene-diesel, condensate-strong solvents, bleaches, and course-grain sand have been found to be detrimental to good cleat maintenance. Recent experience in coalbeds in the Arkoma Basin indicates that a mixture of fresh water with a biocide, combined with a minimal amount of friction reducer, may be the least damaging fracturing fluid. The failure to use gentle fracturing methods and other good production practices elsewhere in a coal bed can even damage production at nearby wells.
[0011] Regardless of whether a fracturing liquid is used in CBM extraction, some means must be provided for the removal of the significant quantity of groundwater expelled as a result of the process. One study found that the average CBM well removed about 12,000 gallons of water per day. Pump jacks and surfactant (soap) introduction are the most common means of removing this water. Pump jacks, which have been used for decades in traditional petroleum extraction, simply pump water out of the well by mechanical means. A pump is placed downhole, and is connected to a rocking-beam activator at the wellhead by means of an interconnected series of rods. Pump jacks are expensive to install, operate, and maintain, particularly in CBM applications where bore cleaning is required more often due to the presence of coal fines. The presence of the pump jack at the end of the well also requires lengthier downtimes when maintenance is performed, reducing the cost-efficiency of the well.
[0012] In contrast to the pump jack method, the surfactant method relies upon the hydrostatic pressure within the well itself to force groundwater up through the borehole and out of the extraction area. The surfactant combines with the groundwater to form a foam, which is pushed back up through the well by hydrostatic pressure. The water/surfactant mixture is then separated from the devolved methane gas and disposed of by appropriate means. Ideally, not all water is removed at the point of CBM extraction; rather, only enough water is removed such that the hydrostatic pressure in the area of the borehole is reduced just enough that the methane bound to the coal will desorb. In this way, damage to the coalbed cleats in the area of the borehole is minimized. Care must be exercised to prevent the surfactant from entering the coal formation, since this too may damage the coalbed cleats and reduce the production rate and lifetime of the well.
[0013] Two methods are commonly used today for the introduction of surfactant into a CBM well. One method is the dropping of “soap sticks” into the well. The soap sticks form a foam as they are contacted by water rising up through the well, thereby forming foam that travels up and out of the well due to hydrostatic pressure. The second method is to attach a small tube inside the main production tube and pour gelled surfactant into this tube. The surfactant travels down the tube through the force of gravity, capillary action, or its own head pressure, eventually depositing the gel into the flow of water in the well and forming a foam. Again, this foam rises back up through the well for eventual removal. Use of either of these methods is believed by the inventor to increase well production on average by 10-20%.
[0014] Although a significant amount of CBM is extracted through vertical drilling methods, horizontal drilling methods have become more common. The general techniques for horizontal drilling are well known, and were developed for conventional extraction of oil and natural gas. In the usual case, the well begins into the ground vertically, then arcs through some degree of curvature to travel in a generally horizontal direction. Horizontal wells thus contain a bend or “elbow,” the severity of which is determined by the drilling technique used. It is believed that horizontal drilling may result in better extraction rates of CBM from many coal beds due to the way in which coalbeds tend to form in long, horizontal strata. One analysis has shown that “face” cleats in coalbeds appear to be more than five times as permeable as “butt” cleats, which form orthogonally to face cleats. A horizontal well can increase productivity by orienting the lateral section of the well across the higher-permeability face cleats. As a result of these effects, the area drained by a horizontal well may be effectively much larger than the area drained by a corresponding vertical well placed into the same coalbed stratum. Horizontal well CBM extraction thus promises greater production from fewer wells in a given coalbed. The first horizontally drilled CBM wells in the Arkoma Basin were put in place around 1998.
[0015] While horizontal drilling promises improved theoretical productivity over vertical drilling in many instances, it raises several problems of its own that are unique to CBM extraction. It may be seen that the deposit of a “soap stick” in a horizontal well will result in the movement of the soap stick only to the bottom of the “elbow” of the well. The soap stick is carried by gravity to this point, but will not proceed past the point where the well turns. Thus this method will form no foam at the end of the well bore at all; foam is only formed at the point where the soap stick comes to rest. The inventor has recognized that increased productivity would result from the production of foam at the end of the well, which is just at the point where the water is being extracted from the coal bed seam. The soap stick will never reach this point.
[0016] Likewise, the method of introducing a surfactant by dripping a gel into the well also suffers when horizontal drilling techniques are used. Gravity, capillary action, or head pressure are the only agents moving the gel down into the well. In actual practice, the lines used to deliver this gel (typically ⅜ inch stainless steel tubing) cannot be made to reach to the bottom of the well, since the weight of the capillary tubing is not sufficient to overcome the frictional force arising from contact with the tubing walls, due to the arc in the horizontal well “elbow.” Again, as in the case of the soap stick, foam will not be formed at the end of the well where it is needed most.
[0017] Another disadvantage of the gel capillary tube approach is that the tubing is employed inside the main production tube in the well; thus when the main production tube plugs or otherwise requires maintenance, the gel delivery tubing will impede efforts to clean, clear, or otherwise maintain the production tube. This is a particular problem in CBM extraction because of the fouling problems presented by coal fines, and the resulting need to regularly swab or clean the well tubing. Finally, since the gel is not introduced under pressure, it cannot adjust to the hydrostatic pressure at the end of the well. This pressure is dependent upon the depth of the well and the height of the water table. If the hydrostatic pressure is significantly less than the gel pressure, then the gel may flow out the production tube and into the coal bed, thereby damaging the coal bed cleats and retarding future production. If the hydrostatic pressure is significantly greater than the gel pressure, then the gel will flow little or not at all, producing minimal foam and impeding removal of groundwater and thus reducing CBM extraction rates.
[0018] While this discussion has focused on CBM extraction, another developing area for the recovery of natural gas from unconventional sources is the extraction of natural gas from sandstone deposits. Sandstone formations with less than 0.1 millidarcy permeability, known as “tight gas sands,” are known to contain significant volumes of natural gas. The United States holds a huge quantity of these sandstones. Some estimates place the total gas-in-place in the United States in tight gas stands to be around 15 quadrillion cubic feet. Only a small portion of this gas is, however, recoverable with existing technology. Annual production in the United States today is about two to three trillion cubic feet. Many of the same problems presented in CBM extraction are also faced by those attempting to recover natural gas from tight gas sands, and thus efforts to overcome problems in CBM extraction may be directly applicable to recovery from tight gas sands as well.
[0019] What is desired then is an apparatus for and method of introducing surfactant into a borehole for CBM extraction, tight sand gas extraction, or other types of gas-recovery options, where such apparatus and method is well-suited to horizontally drilled wells and that produces foam at the tip of the borehole for optimal groundwater removal, while preventing the flow of surfactant into the formation itself in conditions of potentially varying hydrostatic pressure.
BRIEF SUMMARY OF THE INVENTION
[0020] The present invention is directed to an apparatus and method for injecting surfactant into a well utilizing a capillary tube and injection subassembly. The injection subassembly comprises a hydrostatic control valve and nozzle that injects surfactant through an atomizer arrangement at the downhole end of the production tube in the well. The capillary tube travels along the outside of the production tube rather than the inside, thereby leaving the inner portion of the production tube unobstructed. The hydrostatic control valve allows the pressure at which the surfactant is injected to be controlled, such that the surfactant atomizes and shears with the gas and water at the downhole end of the production tube with greater efficiency.
[0021] This apparatus and method results in a number of important advantages over prior art techniques. The surfactant may be directed at exactly the point where it is needed most, that is, at the downhole end of the production tube. By thoroughly mixing the water with surfactant at this point through the use of an atomizer on the valve, water may be more efficiently drawn out of the formation and up through the well tube. Since the surfactant is being directed into the production tube, rather than into the formation itself, there is no danger of significant quantities of surfactant being introduced into the formation, thereby reducing well yields. Even in the case when no water is present, the surfactant will be brought back to the surface by the flow of gas up through the production tube since it leaves the valve in an atomized state. The valve is adjustable to allow for the depth of the well, such that the optimum pressure may be applied to result in good foam body without excessive pressure, thereby minimizing any damage to the formation and maximizing the usable life of the well. Compared to typical surfactant introduction methods that yield increased well production of 10-20%, testing of the present invention in CBM extraction, as well as tight sand gas extraction, has yielded production increases of over 100% in most cases.
[0022] It is therefore an object of the present invention to provide for an apparatus and method for injecting surfactant into a well such that surfactant and water are mixed at or near the end of the well production tube.
[0023] It is a further object of the present invention to provide for an apparatus and method for injecting surfactant into a well such that surfactant and water are well mixed in order to more efficiently move water from the downhole formation.
[0024] It is also an object of the present invention to provide for an apparatus and method for injecting surfactant into a well such that surfactant is inhibited from entering the formation.
[0025] It is also an object of the present invention to provide for an apparatus and method for injecting surfactant into a well such that surfactant does not significantly enter the formation even when no water is present.
[0026] It is also an object of the present invention to provide for an apparatus and method for injecting surfactant into a well such that the pressure at which surfactant is injected is adjustable.
[0027] It is also an object of the present invention to provide for an apparatus and method for injecting surfactant into a well such that a minimum pressure is utilized for drawing water/surfactant from a well, thereby reducing formation damage.
[0028] It is also an object of the present invention to provide for an apparatus and method for injecting surfactant into a well that significantly increases gas yields over conventional surfactant introduction methods.
[0029] These and other features, objects and advantages of the present invention will become better understood from a consideration of the following detailed description of the preferred embodiments and appended claims in conjunction with the drawings as described following:
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0030] FIG. 1 is an elevational view of a downhole tube assembly according to a preferred embodiment of the present invention.
[0031] FIG. 2 is a partial cut-away exploded view of a downhole tube assembly and injection subassembly according to a preferred embodiment of the present invention.
[0032] FIG. 3 is a cut-away view of a valve subassembly according to a preferred embodiment of the present invention.
[0033] FIG. 4 is a cut-away view of a preferred embodiment of the present invention installed in a borehole.
DETAILED DESCRIPTION OF THE INVENTION
[0034] With reference to FIG. 1 , the downhole injection subassembly 10 of a preferred embodiment of the present invention for use in connection with CBM extraction may be described. Although the discussion of the preferred embodiment will focus on CBM extraction, it may be understood that the preferred embodiment is applicable to other gas extraction techniques, including without limitation tight sand gas extraction.
[0035] Downhole injection subassembly 10 is designed for deployment at the end of a production tube for placement in a well. The external portions of downhole injection subassembly 10 are composed of production tube tip 12 and injection sheath 14 . In the preferred embodiment, production tube tip 10 is a tube constructed of steel or other appropriately strong material, threaded to fit onto the downhole end of a production tube. In the preferred embodiments, production tube 10 is sized to fit either of the most common 2⅜ inch or 2⅞ inch production tube sizes used in CBM extraction. In alternative embodiments, other sizes may be accommodated. The distal end of production tube tip 10 may be beveled for ease of entry into the well casing. In the preferred embodiment, the hollow interior of production tube tip 10 is kept clear in order to minimize blockage and facilitate periodic swabbing and cleaning.
[0036] Attached at the downhole end of production tube tip 12 by welding or other appropriate means is injection sheath 14 . Injection sheath 14 protects valve/sprayer subassembly 16 , as shown in FIG. 2 . Like production tube tip 10 , injection sheath 14 may be constructed of steel or another appropriately strong material. In the preferred embodiment, the tip of injection sheath 14 is tapered in a complementary way to that of production tube tip 12 , thereby forming a pointed “nose” on the end of the production tube that eases insertion of the production tube into a well.
[0037] Referring now to FIG. 2 , the components of valve/sprayer subassembly 16 may be described. Nozzle 18 is mounted near the end of production tube tip 12 , and oriented such that surfactant introduced to nozzle 18 is sprayed into production tube tip 12 . In the preferred embodiment, an opening is provided in the side of production tube tip 12 for this purpose. The size of this opening is roughly one-fourth of an inch in diameter in the preferred embodiment, although other sizes may be employed in other embodiments based upon the exact size and construction of nozzle 18 . Nozzle 18 is preferably of the atomizer type, such that surfactant introduced to nozzle 18 under appropriate pressure will be atomized as it leaves nozzle 18 and enters production tube tip 12 . Provided that water is present at the end of production tube tip 12 , this water will be thoroughly mixed with the surfactant thereby forming a foam, which will then be forced to the surface through the production tube along with the evolved gas due to the hydrostatic pressure in the formation.
[0038] Feeding surfactant to nozzle 18 is valve 20 . As explained further below in reference to FIG. 3 , valve 20 opens to allow surfactant into nozzle 18 when the appropriate pressure is applied to the incoming surfactant. The pressure required to open valve 20 will depend upon the hydrostatic pressure at the end of the production tube where valve 20 is located. In the preferred embodiment, valve 20 is threaded on either end to receive nozzle 18 and fitting 22 . Fitting 22 is used to connect valve 20 to capillary tube 24 . In the preferred embodiment, fitting 22 connects to valve 20 using pipe threads, and connects to capillary tube 24 using a compression, flare, or other tube-type fitting. In alternative embodiments, fitting 22 may be omitted if valve 20 is configured so as to connect directly to capillary tube 24 .
[0039] Banding 26 is used to hold capillary tube 26 against production tube tip 12 and the production tube along its length. Banding 26 is preferably thin stainless steel for strength and corrosion-resistance, but other appropriate flexible and strong materials may be substituted. In the preferred embodiment, banding 26 is placed along capillary tube 24 roughly every sixty feet along its length. At the surface, capillary tube 24 may be routed through a wing port in the well head (not shown) and packed off with a tube connection to pipe thread fitting similar to fitting 22 (not shown). Capillary tube 24 may then be connected to a pump mechanism providing surfactant under pressure.
[0040] Referring to FIG. 3 , the internal components of valve 20 may now be described. Seat 28 and body 30 of valve 20 define a passageway through which surfactant may pass from capillary tube 24 (by way of fitting 22 ) into nozzle 18 , and then out into production tube tip 12 . Seat 28 and valve body 30 may be fitted together as by threading. Lower O-ring 40 provides a positive seal between seat 28 and body 30 of valve 20 . Lower O-ring may be of conventional type, such as formed with silicone, whereby a liquid-proof seal is formed. In the preferred embodiment, Seat 28 and valve body 30 are preferably formed of stainless steel, brass, or other sufficiently durable and corrosion-resistant materials.
[0041] Flow of surfactant through valve 20 is controlled by the position of ball 36 . Ball 36 is preferably a ⅜ inch diameter stainless steel ball bearing. Ball 36 may seat against upper O-ring 38 , which, like lower O-ring 40 , is preferably formed of silicon or some other material capable of producing a liquid-proof seal. When seated against upper O-ring 38 at seat 28 , ball 36 stops the flow of surfactant out of valve 20 and into nozzle 18 .
[0042] Ball 36 is resiliently held in place against upper O-ring 38 by spring 34 . Spring 34 may be formed of stainless steel or other sufficiently strong, resilient, and corrosion-resistant material. The inventor is unaware of any commercially available spring with the proper force constant, and thus spring 34 in the preferred-embodiment is custom built for this application. Spring follower 32 fits between spring 34 and ball 36 in order to provide proper placement of ball 36 with respect to spring 34 . As will be evident from this arrangement, a sufficient amount of pressure placed on the surfactant behind ball 36 within valve seat 28 will overcome the force of spring 34 , forcing ball 36 away from upper o-ring 38 and allowing surfactant to flow around ball 36 , into the interior of valve body 30 around spring 34 , and out of valve body 30 and into nozzle 18 . Once this pressure is released, or reduced such that it may again be overcome by the force of spring 34 , valve 20 will again close and prevent the flow of surfactant through valve 20 . Valve 20 thus operates as a type of one-way check valve, regulating the flow of surfactant into nozzle 18 and ensuring that surfactant only reaches nozzle 18 if a sufficient pressure is provided. This ensures that surfactant will be properly atomized by nozzle 18 upon disposition into production tube tip 12 regardless of the downhole hydrostatic pressure within the expected range of operation.
[0043] Referring now to FIG. 4 , the use of the invention with respect to the recovery of gas in a CBM well may be described. CBM wells are generally lined with a casing 44 as drilled to protect the well from collapse. The most common casing 44 sizes are 4½ inches and 5½ inches. Since the most common production tubing sizes are 2⅜ inches and 2⅞ inches, this size disparity leaves sufficient room for production tube 42 to be easily inserted and removed from casing 44 . The size disparity also allows additional room for capillary tube 24 to be mounted to the exterior of production tube 42 , with periodic banding 26 as described above, in order to feed valve/sprayer subassembly 16 .
[0044] The above-ground components of the preferred embodiment include a chemical pump, soap tank, and defoamer tank (not shown) as are known in the art. Pumps such as the Texstream Series 5000 chemical injectors, available from Texstream Operations of Houston, Tex., may be employed. The soap tank may be a standard drum to contain surfactant material that is fed through the pump. The defoamer tank, the purpose of which is to separate gas from the surfactant for delivery, may be constructed from a standard reservoir with a top-mounted gas outlet.
[0045] Now with reference again to FIGS. 1-4 , a method of recovering gas from a well according to a preferred embodiment of the present invention may be described. A horizontal well is drilled and cased with casing 44 in a manner as known in the art. Valve/sprayer subassembly 16 is then fitted to downhole injection subassembly 10 , such that nozzle 18 is situated to direct the spray of surfactant into production tube tip 12 . Downhole injection subassembly 10 is then fitted to the downhole end of production tube 42 . Capillary tube 24 is next attached to fitting 22 of downhole injection subassembly 10 . It may be noted that capillary tube 24 is preferably provided on a large roll, such that it may be fed forward as production tube 42 is fed into casing 44 . At regular intervals, preferably approximately every 60 feet or so, capillary tube 24 is fastened to production tube 42 using banding 26 . This operation continues until production tube tip 12 reaches the bottom of the well, situated at the formation of interest for gas recovery.
[0046] The arrangement described herein with respect to the preferred embodiment provides for a production tube 42 that is free of all obstacles, allowing unrestricted outflow of gas through production tube 42 to the surface. This feature is particularly important for gas production in “dirty” wells such as those drilled into coal formations for CBM recovery. In such environments, an unusually high number of contaminants will enter the well. It will thus be necessary to periodically swab production tube 42 and to remove coal plugs from production tube 42 . With production tube 42 remaining otherwise open, it is a simple matter to run a swab the length of production tube 42 in order to clear obstacles. Otherwise, it would often be necessary to remove production tube 42 from casing 44 in order to perform maintenance. Removal of production tube 42 increases the equipment maintenance cost associated with the CBM extraction operation, and further causes significant downtime during CBM extraction.
[0047] As gas recovery begins, surfactant is forced into capillary tube 24 under sufficient force to overcome the combined force of spring 34 and the downhole hydrostatic pressure and thereby open valve 20 . In the preferred embodiment, valve 20 is constructed such that surfactant is injected through nozzle 18 at a pressure of no less than 300 pounds per square inch. This pressure ensures that the surfactant is atomized upon entry into production tube tip 10 , thereby creating the best foam when mixed with available water. The production of high-quality foam lowers the hydrostatic head pressure at the bottom of the well, allowing gas to flow up production tube 42 along with the foam utilizing only the hydrostatic pressure at the bottom of the well. The elimination of external pressure to force gas upward minimizes the damage that might otherwise occur to the formations from which gas is recovered, which would lower production rates and expected well lifetime.
[0048] It may be noted that the feature of directing nozzle 18 into production tube tip 12 , rather than into the formation, is particularly important in CBM recovery. The long lateral strata common to coal formations do not allow for a homogenous porosity state of coal/gas. Thus the water and gas influx across the face of the formation are very erratic in typical horizontal wells. If it should occur that the hydrostatic pressure drops and water is not present at production tube tip 12 , the surfactant still will be carried in an atomized state up and out of the production tube 42 , rather than into the formation. As already noted, surfactant introduced into the formation will lower the output and operational lifetime of the well.
[0049] In addition, the ability to vary the pressure at valve 20 is particularly useful with regard to such wells due to the erratic nature of the hydrostatic pressure across a formation. The pressure of the surfactant introduced to valve 20 is varied in response to an observation of foam quality at the output of production tube 42 . In the preferred embodiment this operation is performed by visual inspection and hand manipulation of the pressure, although automatic sensing equipment could be developed and employed in alternative embodiments of the present invention. The pressure of surfactant can be optimized in a matter of minutes, since the only delay in determining foam quality is the time that is required for foam to reach the top of production tube 42 . Previous methods would require days of production and subsequent yield analysis before an optimum surfactant introduction rate could be determined, due to the delay caused by slowly trickling surfactant down the casing of production tube 42 . The pressure at valve 20 can also be adjusted according to well depth, which is a factor in the hydrostatic pressure present. In the preferred embodiment, the pressure at valve 20 may be adjusted to correspond to expected hydrostatic pressures at depths of anywhere from 500 to 20,000 feet.
[0050] The present invention has been described with reference to certain preferred and alternative embodiments that are intended to be exemplary only and not limiting to the full scope of the present invention as set forth in the appended claims. | An apparatus and method for injecting surfactant into a well for coal bed methane (CBM) recovery, tight sand gas extraction, and other gas extraction techniques provides for the mixing of surfactant and water near the downhole end of the well, maximizing water removal for gas recovery. The apparatus may include a check valve that feeds a nozzle to atomize the spray of surfactant into the well production tube. Surfactant is not sprayed directly into the formation, thereby protecting the formation from damage and recovering surfactant even in the case where water is not present. The capillary tube feeding surfactant to the check valve may be placed externally to the production tube to facilitate ease of cleaning and clearing of the production tube. | 4 |
TECHNICAL FIELD
[0001] The present invention relates generally to electrical computing systems, and more particularly to tools for shaping network traffic in a communication system.
BACKGROUND
[0002] There are many emerging trends in the communications world, including the increase in network technology and the proliferation of data networks. To ensure security of communications and to avoid networking congestion problems, network designers have either incorporated security appliances, such as firewalls and virtual private networks, and traffic management devices in their systems or enhanced their routers with these functionalities.
[0003] A firewall is an Internet security appliance designed to screen traffic coming into and out of a network location. A virtual private network provides a secure connection through a public network such as the Internet, between two or more distant network appliances using a virtual private networking technology. Traffic management devices are used to monitor and/or control traffic passing through network devices to maintain a network's quality-of-service (QOS) level.
[0004] Traffic shaping is a technique for regulating traffic. Traffic shaping refers to a process of analyzing an allocated bandwidth utilized by various types of network traffic through a network appliance. Traffic shaping policies can be used to prioritize users in accordance with an IP address or other criteria to provide different levels of service to different users of a network appliance.
[0005] A leaky bucket is one example of a conventional technique used to control traffic flow. A splash is added to the bucket for each incoming byte received by the network appliance when the bucket is not full. The splash results in an increment in a counter associated with the bucket. The bucket leaks away at a constant rate (bytes are allowed to pass from the bucket through the network appliance). When the bucket is full (the counter is at a maximum value), bytes cannot pass through the network appliance (i.e., no additional bytes can be added to the bucket). As the bucket begins to empty in accordance with the leak rate, bytes once again can begin to be added to the bucket so that they can be moved through the network appliance. Leaky buckets are characterized by three parameters: the sustained information rate (SIR), the peak information rate (PIR) and the burst length (BL). The SIR is bound by the long-term data rate and defines the rate that data leaks from the bucket. BL defines the depth of the bucket and is equal to the maximum amount of data allowed to be passed when the bucket is empty. PIR defines the maximum rate at which the source can send data.
[0006] A token bucket is another example of a conventional technique used to control traffic flow. With token buckets, tokens are added to the bucket at a constant rate of the SIR. The token is a convention that is used to represent a defined unit of data (e.g., a byte or a packet). The token bucket has a depth of BL. When the token bucket is full no more tokens can be added to the bucket. When data comes in to the network appliance, if there are enough tokens in the token bucket, the data will be passed. Otherwise, the data will be held until the token bucket accumulates enough tokens.
[0007] A credit/debit token bucket is another example of a conventional technique used to control traffic flow. In the example discussed above for the token bucket, no data can be passed when there are insufficient tokens in the token bucket. This may cause some unacceptable delays. A credit/debit token bucket allows for oversubscription of tokens. Unlike normal token buckets, the number of tokens in a credit/debit token bucket can be negative. Based on the number of tokens in the bucket, a credit/debit token bucket can be in either one of the three states. If the number of tokens is positive the bucket has credit. If the number of tokens is negative the bucket owes a debit. Otherwise the bucket is in an even state. The operation of a conventional credit/debit token bucket is as follows. Tokens are added to a credit/debit token bucket in the same way as added to a normal token bucket. The difference between a normal token bucket and credit/debit token bucket is how incoming data is handled. In a credit/debit token bucket, as long as the data comes in and the credit/debit token bucket is in the credit or even state, the data is granted permission to pass and the number of tokens is decremented accordingly. After the decrementing operation (to remove the corresponding number of tokens from the bucket based on the amount of data that was passed), the number of tokens in the bucket can be negative, even, or still positive. If data comes in while the credit/debit token bucket is in a debit state, the data is held until the credit/debit bucket returns to the credit or even state (i.e., pays off all of its debt). Thereafter, the network appliance can pass the held data.
[0008] As described above a bucket has a definite depth. For example, a token bucket can accept a definite number of tokens before it becomes full. Traditionally, when the bucket became full, the excess (e.g., the excessive tokens) was discarded (i.e., to satisfy a guaranteed bandwidth requirement). If an unlimited or undefined depth bucket were used then the underlying policy may become oversubscribed. In order to ensure that oversubscription does not occur, traditionally these excessive tokens were discarded. What would be desirable is a system that would allow a bucket to share its excess while still providing a guaranteed bandwidth to an associated policy.
SUMMARY
[0009] In one aspect the invention provides a method for allocating bandwidth in a network appliance where the network appliance includes a plurality of guaranteed bandwidth buckets used to evaluate when to pass traffic through the network appliance. The method includes providing a shared bandwidth bucket associated with a plurality of the guaranteed bandwidth buckets, allocating bandwidth to the shared bandwidth bucket based on the underutilization of bandwidth in the plurality of guaranteed bandwidth buckets and sharing excess bandwidth developed from the underutilization of the guaranteed bandwidth allocated to the individual guaranteed bandwidth buckets. The step of sharing includes borrowing bandwidth from the shared bandwidth bucket by a respective guaranteed bandwidth bucket to allow traffic to pass immediately through the network appliance.
[0010] Aspects of the invention can include one or more of the following features. The shared bandwidth bucket can be a token bucket. The guaranteed bandwidth buckets can be token buckets or credit/debit buckets. Each guaranteed bandwidth bucket can be associated with a traffic shaping policy. A plurality of guaranteed bandwidth buckets can be associated with a single traffic shaping policy. The traffic shaping policy can screen based on IP address. The traffic shaping policy can screen based on the source IP address, the destination IP address, the protocol type, UPD/TCP port number, type of service requested and/or the traffic content.
[0011] In another aspect the invention provides a method for allocating bandwidth in a network appliance. The method includes defining a guaranteed bandwidth allocation for a first policy for passing traffic through the network appliance including using a first bucket to allocate the guaranteed bandwidth. A guaranteed bandwidth allocation for a second policy for passing traffic through the network appliance is also defined including using a second bucket to allocate the guaranteed bandwidth. Excess bandwidth developed from the underutilization of the guaranteed bandwidth allocated to the first and second buckets is shared. Sharing includes providing a shared bandwidth bucket associated with first and second buckets and borrowing bandwidth from the shared bandwidth bucket by one of the first and second buckets when the respective bucket has insufficient bandwidth to allow traffic to pass immediately through the network appliance.
[0012] In another aspect, the invention provides an apparatus for allocating bandwidth in a network appliance where the network appliance includes a plurality of guaranteed bandwidth buckets used to evaluate when to pass traffic through the network appliance. The apparatus includes a shared bandwidth bucket associated with a plurality of the guaranteed bandwidth buckets, means for allocating bandwidth to the shared bandwidth bucket based on the underutilization of bandwidth in the plurality of guaranteed bandwidth buckets and a scheduler. The scheduler is operable to evaluate a packet to determine if a traffic shaping policy should be applied to a given packet, evaluate a guaranteed bandwidth bucket associated with an identified traffic shaping policy, determine when the guaranteed bandwidth bucket associated with an identified traffic shaping policy has insufficient capacity to support a transfer of the packet through the network and borrow bandwidth from the shared bandwidth bucket by a respective guaranteed bandwidth bucket to allow traffic to pass immediately through the network appliance.
[0013] Aspects of the invention can include one or more of the following advantages. Cascaded buckets are provided that support a guaranteed bandwidth for a policy while also allowing for sharing of that guaranteed bandwidth among other policies in the event that the bandwidth is under utilized. The shared bandwidth supports the elimination of static bandwidth allocation while guaranteed bandwidth is not compromised. By allowing the network appliance to share the unused guaranteed bandwidth, the bandwidth utilization of the network appliance can be dramatically improved.
[0014] The details of one or more embodiments of the invention are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the invention will be apparent from the description and drawings, and from the claims.
DESCRIPTION OF DRAWINGS
[0015] FIG. 1 is a shows a block diagram for a network appliance that includes cascaded buckets.
[0016] FIG. 2 is a flow diagram of a process for passing data through the network appliance of FIG. 1 .
[0017] FIG. 3 is a flow diagram of a method for incrementing a guaranteed bandwidth bucket.
[0018] Like reference symbols in the various drawings indicate like elements.
DETAILED DESCRIPTION
[0019] Referring now to FIG. 1 , a network appliance 100 that includes traffic shaping policy tools is shown. Network appliance 100 includes a plurality of input ports 102 each of which includes an input queue 104 , an output queue 106 , a scheduler 108 and a forwarding engine 120 . Associated with scheduler 108 are a token system 110 , increment engine 112 and decrement engine 114 .
[0020] As data is received at an input port 102 , the data is transported into the input queue 104 . Input queue 104 acts as a first in/first out buffer for holding packets that are received from the input port 102 . Scheduler 108 periodically checks the status of token system 110 to determine whether or not a data packet stored in the input queue 104 can be passed to the output queue 106 . When scheduler 108 determines that there are sufficient tokens in the token system 110 , then a packet may be transferred from the input queue 104 to the output queue 106 . Thereafter, packets can be passed in order from the output queue 108 to other portions of the network appliance by forwarding engine 120 . At a predetermined rate, increment engine 112 adds tokens to the token system 110 . Similarly, as packets are transferred from the input queue 104 to the output queue 106 , decrement engine 114 removes the appropriate amount of tokens from the token system 110 .
[0021] Token system 110 includes a plurality of traffic shaping policy buckets. As described above, a traffic shaping policy is a convention used to ensure levels of service to users of the network appliance. A policy is any user-defined criteria for grouping input received at the network appliance. The policy can be based on IP address or other constraints in order to manage the traffic from one particular user defined group. One or more policies can be evaluated for each packet. For example, one policy may screen based on an IP address for the packet sender. Another policy may screen based on a destination IP address. Other parameters other than IP address can be used in constructing a traffic shaping policy.
[0022] In one implementation, for each policy, token system 110 includes at least three buckets 130 a , 130 b and 130 c . Each first bucket 130 a , also referred to as a maximum bandwidth allocation bucket, is configured as a conventional token bucket that has a SIR that is equal to the maximum rate at which data of the policy type can be sent. Tokens are added to the first bucket 130 a at a rate to limit the bandwidth allocated for the given policy to the maximum bandwidth allocation assigned to the given policy. If the balance (in tokens) in the maximum bandwidth bucket 130 a is greater than or equal to zero, then the scheduler 108 will allow the packet to pass from the input queue 104 to the output queue 106 (assuming that the balances in the second and third buckets are appropriate). However, if the balance in the maximum bandwidth bucket 130 a is less than zero, then no packets of this type (that include the policy parameter) will pass from the input queue 104 to the output queue 106 at this time. This guarantees that the particular policy cannot be oversubscribed.
[0023] Second bucket 130 b is a guaranteed bandwidth bucket. The guaranteed bandwidth bucket 130 b operates in a similar fashion to the maximum bandwidth bucket 130 a and includes an SIR set to be the guaranteed bandwidth allocation for the policy. When a packet is received (assuming that the maximum bandwidth allocation bucket has a balance that is greater than or equal to 0), then the balance of the guaranteed bandwidth bucket 130 b is checked to determine if the packet's size is greater than or less than the balance in the guaranteed bandwidth bucket 130 b . If the balance of tokens is greater than the packet's size, then scheduler 108 allows the packet to be transferred from the input queue 104 to the output queue 106 . If the balance is less than the packet's size, then an attempt is made to borrow from the third bucket 130 c.
[0024] The third bucket is referred to as the shared bandwidth bucket 130 c . The shared bandwidth bucket 130 c has tokens added every time one or more of the guaranteed bandwidth buckets reaches its peak allocation. At a next time one or more tokens are scheduled to be added to an otherwise full guaranteed bandwidth bucket 130 b (tokens which would otherwise be discarded), the token(s) are stored in the shared bandwidth bucket 130 c . In one implementation, the shared bandwidth bucket 130 c is shared among plural members (guaranteed bandwidth buckets 130 b ) of the same traffic shaping policy group. Traffic shaping policies can be grouped together by many different criteria such as physical interface and priority. Policies can also be grouped in a hierarchical way such that there are subgroups in a group. In operation, if the balance of a guaranteed bandwidth bucket 130 b for any member of a policy group is less than the packet size, an attempt is made to borrow from the shared bandwidth bucket 130 c . If the borrowing attempt fails, that is, if there are insufficient tokens in the shared bandwidth bucket 130 c , then the packet will not be transferred to the output queue 106 . Alternatively, if there are sufficient tokens in the shared bandwidth bucket 130 c to allow for a borrowing operation, then a sufficient number of credits are transferred to the guaranteed bandwidth bucket that attempted the borrowing. Thereafter, the scheduler enables the transfer of the packet from the input queue 104 to the output queue 106 . After the transfer, the decrement engine 114 removes the appropriate number of tokens from the shared bandwidth bucket 130 c (i.e., the number borrowed) and from the appropriate guaranteed bandwidth bucket 130 b (i.e., the number of tokens required to pass the packet).
[0025] Referring now to FIG. 2 , a process used by the scheduler 108 for determining when to transfer packets from the input queue 104 to the output queue 106 is shown. The process begins as the scheduler checks to determine if any packets are stored in the input queue ( 202 ). If not, the process waits for a packet to arrive and continues at step 202 . Otherwise, a next packet in the input queue is identified ( 204 ). A check is made to determine if a policy screen should be applied to the packet ( 206 ). As described above, a policy screen includes one or more policy parameters. The policy parameters define the screening parameters for the policy. An example of a policy parameter is the packet's IP address. Packets can be screened based on destination, source or both. In addition, traffic can be screened based upon protocol type, UPD/TCP port number, type of service and traffic content such as websites. If no policy screen is to be applied, then the process continues at step 250 where the packet is transferred from the input queue 104 to the output queue 106 .
[0026] If a policy is to be enforced, a cheek is made to determine if the size of the packet exceeds the balance of the maximum bandwidth bucket 130 a associated with the identified policy ( 208 ). If the size exceeds the balance, then the process continues at step 202 without transferring the packet from the input queue 104 to the output queue 106 . If the size does not exceed the balance in step 208 , the scheduler checks to determine if the size of the packet exceeds the balance of the guaranteed bandwidth bucket 130 b for the policy ( 210 ). If the size does not exceed the balance in step 210 , then the process continues at step 250 where the packet is transferred from the input queue 104 to the output queue 106 .
[0027] If the size exceeds the balance in step 210 , then the scheduler determines if there are sufficient tokens in the shared bandwidth bucket 130 c associated with the policy to pass the packet ( 212 ). If there are insufficient tokens in the shared bandwidth bucket 130 c , the process continues at step 202 without transferring the packet from the input queue 104 to the output queue 106 . If there are sufficient tokens in the shared bandwidth bucket 130 c , then the appropriate amount of tokens is transferred (so that the balance in the guaranteed bandwidth bucket 130 b equals or exceeds the size of the packet) from the shared bandwidth bucket 130 c to the requesting guaranteed bandwidth bucket 130 b ( 214 ). In one implementation, the tokens are physically transferred from the shared bandwidth bucket to the guaranteed bandwidth bucket during a borrowing operation. Alternatively, the tokens can be virtually passed, that is, allocated to the guaranteed bandwidth bucket without requiring them to be physically transferred. A check is made to determine if the packet needs to be screened against any other policies ( 216 ), if so, the next policy is identified ( 218 ) and the process continues at step 208 .
[0028] In step 250 , the scheduler 108 allows the transfer of the packet from the input queue 104 to the output queue 106 . At the time of transfer, the appropriate number of tokens is decremented from the guaranteed bandwidth bucket and maximum bandwidth bucket for each policy used to screen the packet ( 252 ). Thereafter the process continues at step 202 .
[0029] Referring now to FIG. 3 , a flow diagram for a method for incrementing the guaranteed bandwidth buckets 130 b is shown. The process begins by identifying a guaranteed bandwidth for the policy associated with the given guaranteed bandwidth bucket ( 302 ). A frequency for incrementing ( 304 ) and an amount of tokens to be added at each increment step are identified ( 306 ). A check is then made to determine if the guaranteed bandwidth bucket should be updated (based on the frequency data) ( 308 ). If not, the process continues at step 308 waiting for the next update period. If an update is warranted, then a check is made to determine if there is sufficient space in the guaranteed bandwidth bucket to accept the amount of tokens to be added ( 310 ). If there is enough space, then the tokens are added to the guaranteed bandwidth bucket ( 312 ) and the process continues at step 308 .
[0030] If the check at step 310 fails, then the guaranteed bandwidth bucket is filled to its capacity ( 314 ). Thereafter, a check is made to determine if the guaranteed bandwidth bucket has an associated shared bandwidth bucket ( 316 ). If not, the process continues at step 308 . If the guaranteed bandwidth bucket has an associated shared bandwidth bucket then a check is made to determine there is sufficient space in the shared bandwidth bucket to accept the amount of excess tokens ( 318 ). If there is not enough space, then the shared bandwidth bucket is filled to its capacity ( 320 ) and the process continues at step 308 . If there is enough space, then all of the excess tokens are added to the shared bandwidth bucket ( 322 ) and the process continues at step 308 .
[0031] Credit/Debit Guaranteed Bandwidth Bucket
[0032] In one implementation, the guaranteed bandwidth bucket 130 b can be a credit/debit bucket. In this implementation, the maximum bandwidth bucket 130 a is a conventional token bucket (i.e., no-debt bucket). The guaranteed bandwidth bucket 130 b is a credit/debit bucket that is allowed to operate in a debt mode. The shared bandwidth bucket 130 c is a conventional token (i.e., no-debt) bucket that includes the borrowing provisions set forth above.
[0033] In operation, the maximum bandwidth bucket 130 a operates (is incremented and decremented) as described above to ensure the policy is not oversubscribed. Assuming that the number of tokens in the maximum bandwidth bucket is greater than or equal to zero, then the scheduler checks the guaranteed bandwidth bucket (the credit/debit version) to determine if the number of tokens is greater than the packet size. If so, then the packet is passed in the system and the appropriate number of tokens is debited from both the maximum bandwidth bucket and the guaranteed bandwidth bucket. If the number of tokens in the guaranteed bandwidth bucket 130 b is greater than 0 however, less than the packet size then the packet passes, but there is no borrowing operation that occurs. The packet passes in accordance with the standard credit/debit protocol associated with a credit/debit bucket. If however the number of tokens in the guaranteed bandwidth bucket 130 b is less than 0, the scheduler attempts to borrow (from an associated shared bandwidth bucket 130 c , if any).
[0034] In one implementation, the scheduler may borrow only to cover the debt (incurred for passing the packet). Alternatively, in another implementation, the scheduler may borrow to cover the packet size itself. In a third implementation, the scheduler may borrow to cover both the debt as well as the packet size.
[0035] Two-bucket System
[0036] In one implementation, token system 110 includes only cascaded pairs of buckets. In this implementation, token system 110 includes a plurality of guaranteed bandwidth buckets 130 b , one or more for each policy that is supported, and one or more shared bandwidth buckets (to allow sharing among policies or in a policy). Each of the guaranteed bandwidth buckets operates as described above. The guaranteed bandwidth buckets can either be conventional token buckets, leaky buckets, or credit/debit buckets. When a guaranteed bandwidth bucket does not have sufficient tokens/space to allow a packet to pass, the scheduler can attempt to borrow from a shared bandwidth bucket associated with a given policy (or policies).
[0037] The shared bandwidth bucket can support plural different policies. The network appliance can provide a dynamic allocation of resources that supports both guaranteed bandwidth among policies and also a sharing of guaranteed bandwidth among members of one or more policies.
[0038] Priority Information
[0039] In an alternative implementation, when a guaranteed bandwidth bucket attempts to borrow from a shared bandwidth bucket, the scheduler considers priority data when determining whether borrowing is allowed. Each guaranteed bandwidth bucket can be assigned a priority. The priority data can be used to determine when borrowing is allowed. The priority data can be set based on use of the shared bandwidth bucket. Depending on the priority level setting for a given guaranteed bandwidth bucket, the borrowing operation may be disallowed. The priority level can be used to determine how a policy/policies will share the bandwidth in the shared bucket that is available. The higher priority policy can be allocated the shared bandwidth before a lower priority policy.
[0040] The present invention can be used by any traffic shaper to enforce traffic shaping policies. The traffic shaper can be a dedicated device such as a package shaper or a multi-function device with traffic shaping functionality such as a router or a firewall engine. The present invention allows a traffic shaper to dynamically allocate guaranteed bandwidth for a policy. System administrators can avoid the limitations of static allocations while guaranteed bandwidth is not compromised
[0041] A number of embodiments of the invention have been described. Nevertheless, it will be understood that various modifications may be made without departing from the spirit and scope of the invention. Accordingly, other embodiments are within the scope of the following claims. | In one aspect the invention provides a method for allocating bandwidth in a network appliance where the network appliance includes a plurality of guaranteed bandwidth buckets used to evaluate when to pass traffic through the network appliance. The method includes providing a shared bandwidth bucket associated with a plurality of the guaranteed bandwidth buckets, allocating bandwidth to the shared bandwidth bucket based on the underutilization of bandwidth in the plurality of guaranteed bandwidth buckets and sharing excess bandwidth developed from the underutilization of the guaranteed bandwidth allocated to the individual guaranteed bandwidth buckets. The step of sharing includes borrowing bandwidth from the shared bandwidth bucket by a respective guaranteed bandwidth bucket to allow traffic to pass immediately through the network appliance. | 7 |
The present invention relates to a device for shaping a cue stick tip.
BACKGROUND OF THE INVENTION
The following patents relate to devices for shaping cue stick tips.
U.S. Pat. No. 221,164 describes a billiard-cue chalk block having sand paper secured to the bottom and sides of the block. The top surface of the chalk is formed with a concavity adapted to fit the tip of the cue, and the sandpaper at the bottom may also be formed with a similar depression for occasional use.
U.S. Pat. No. 284,548 describes a billiard cue trimmer comprising a block with a series of chambers, each having a concave bottom covered with sandpaper or emery cloth. The curvature of each bottom is graduated in accordance with a fixed standard, and the scale of curvature is indicated by an appropriate symbol so that a cue tip can be trimmed to any convex contour desired by a player.
U.S. Pat. No. 1,259,136 describes a device for trimming billiard cue tips including a receptacle having a bottom and an annular wall. A disc-like abrading surface is provided at the bottom of the receptacle, and the annular wall is notched or serrated to form a file-like surface to engage the edge of the cue tip.
U.S. Pat. No. 3,728,828 describes a cue tip trimmer which is an abrasive wheel, shaped to easily trim cue stick tips and refinish them as they are worn during play. The trimmer consists of a solid cylindrically shaped abrasive wheel having a cylindrical recess which terminates within the wheel in a concave shape recess.
A need exists for a device which will enable a player of a table ball game, such as pool, snooker or billiards, to reform the tip of the cue stick which has become dimpled or distorted due to repeated cue tip-ball contacts so that the tip is maintained with a smooth, uniform exterior contour. The exterior contour of the tip changes constantly during a pool game as a result of the repeated cue-ball contacts. These variations in the external contour of the tip adversely affect the accuracy of a shot, since the cue ball upon being struck by the distorted tip will likely not roll in the particular desired direction. To date, the usual method by which players compensate for the changes in the exterior contour of the tip is by "chalking" the tip. However, chalking does not reform the tip which has been deformed in tip cue-ball contact, but merely aids in increasing friction between the cue stick tip and the cue ball. Thus, a need exists for a tool which will enable a player to eliminate the variations in tip form, including contour, smoothness, tip density and uniform surface.
SUMMARY OF THE INVENTION
According to one aspect of the present invention, there is provided a device for shaping a cue stick tip comprising a body, a scuffing means mounted in said body for rough cutting the cue stick tip to impart a desired overall shape to the tip. A tip reforming means is also mounted in the body for imparting a uniform exterior contour to the tip.
According to another aspect of the present invention, there is provided a device for shaping a cue stick tip, comprising a body having a tip reforming means mounted in the body for imparting a uniform exterior contour to the tip.
According to a further aspect of the present invention, there is provided a device for shaping a cue stick tip, comprising a body, a chalking means mounted within in the body for applying chalk to the tip, and a tip reforming means mounted in the body for imparting a smooth and uniform exterior contour to the tip.
BRIEF DESCRIPTION OF THE DRAWINGS
Embodiment of the invention will now be described in more detail, with reference to the accompanying drawings, in which:
FIG. 1 is a perspective view of the device of the invention showing a tip reforming means mounted in one end of the device and about to receive a cue stick tip;
FIG. 2 is a perspective view of the other end of the device of FIG. 1 showing the scuffing means;
FIG. 3 is a cross-sectional side view taken along the line 3--3 in FIG. 1; and
FIG. 4 is a partial cross-sectional view of another embodiment of the invention having a tip reforming means at one end and a chalk insert at the other end.
DETAILED DESCRIPTION OF THE INVENTION
Referring to FIG. 1, the device of the invention, generally referenced 2, comprises a body 4 having ends 6 and 8. At end 6 there is provided a tip reformer 10, and at end 8 there is provided a scuffer 12 (see FIG. 2).
The body 4 is comprised of an elongate member having a cross-sectional configuration such that the device does not roll on a flat surface. The device illustrated in FIGS. 1 and 2 is hexagonal in cross-section, but this cross-sectional configuration is not critical, and the device could equally well be triangular, or polygonal in cross-section, to reduce the tendency of the device rolling on a flat surface.
The body 4 may be fabricated from any suitable material, such as metal or a non-metal or plastics material. According to a preferred embodiment, the device is fabricated from hexagonal aluminum solid stock that can be of various colors. However, the device could equally well be fabricated from a plastics material, which might be transparent or colored with any desired color. The provision of one or more flat faces on he body 4 has the advantage that the owner's name serial number or initials can be readily inscribed on the device, thereby providing a ready means of associating the device with its owner.
The tip reformer 10 is mounted in the end 6 of the device. The tip reformer 10 is preferably fabricated from solid cylindrical stainless steel stock 14 or stamped and chrome plated and comprises a hemispherical highly polished concavity 16 formed in the end of the stock 14. The concavity 16 is shaped so as to enable the tip of the cue to be repeatedly reformed with a uniformly smooth exterior contour. The stock 14 is fixedly received in a corresponding cylindrical aperture 18 formed in the end of the body. The stock 14 is mounted in the aperture by any suitable method, such as by a frictional press fit or by the use of a suitable adhesive.
The scuffer 12 is provided at the end 8 of the device. The scuffer 12 is preferably formed from stainless steel cylindrical solid stock 20 or stamped and includes a hemispherical concavity 22 having sharp protrusions 24 formed on the concave surface of the concavity 22. The sharp protrusions 24 may be formed of any suitable abrasive material, for example silicon carbide chips which are silver brazed onto the concave surface of the concavity 22. As with the stock 14, th stock 20 is fixedly received in a cylindrical aperture 26 formed in the end 8 of the body 4. The stock 20 may be mounted in the cylindrical aperture 26 using the same means as for the stock 14, for example by frictional press fit or by the use of an appropriate adhesive.
In order to assist the user in carrying the device, a carrying means such as a chain 28 is provided which extends through an aperture 30 in the body 4. As can be seen from FIG. 3, the aperture 30 is disposed nearer the end 6 than the end 8 so that the device 4 is counterbalanced downward when held by the chain 28.
FIG. 4 shows an alternative embodiment of the device of the invention wherein the scuffer 12 is replaced by a chalk insert 32. The chalk insert 32 is received within an appropriately shaped cavity 34 in the end of the body 4. The chalk insert 32 is preferably press fitted into the cavity 34 so that when the chalk has been worn down and a new insert is required, it is a simple matter to remove residual chalk from the aperture 34 using a scraper or the like. the chalk insert 32 may optionally be provided at the exposed end with a concavity 36 in order to facilitate uniform application of chalk to the cue tip.
As is well known, cue tip chalk is readily available in the form of cubicular blocks, and players more often than not will possess their own preferred chalk blocks. In view of this, another embodiment of the invention, provides a device having only a tip reformer 10 at the end 6, with the other end 8 being free of a scuffer or chalk insert. Such an embodiment would appear as that shown in FIG. 1.
In use of the device, cue tip 38 of cue stick 40 is reformed by placing the tip 38, typically having a leather outer covering, into the concavity 16 and manually applying pressure and a rotating movement of the concavity about the tip 38. This serves to reform the tip and eliminate dimples and other variations in the tip form, and imparts to the tip the desired smoothness, contour, density and uniformity of surface without abrading or otherwise wearing the tip away. The tip reformer is designed to be used by the player frequently during the game since the tip is quickly dimpled and deformed by repeated tip cue-ball contacts, thereby increasing the likelihood of inaccurate shots.
When the tip has become badly deformed or worn, or when the cue stick 40 is provided with a new tip 38, the scuffer is used to coarsely abrade the tip to the approximate desired shape. New or replaced tips are cylindrical in shape, and are handformed by various means to the desired shape. The desired shape of cue tip varies greatly from player to player, and the scuffer enables the desired external tip configuration to be quickly and easily achieved. After scuffing has been completed, the final proper tip configuration can be readily obtained by use of the tip reformer as described above. Chalking the tip after reforming then puts the tip in good condition for playing.
The present invention provides a cue tip device which substantially if not completely eliminates variations in tip configuration, and enables the player to repeatedly obtain a uniformity of tip contour, surface smoothness and tip density. These factors all contribute to whether the cue tip gives rise to an accurate shot upon contact with the cue ball, since changes in any one of the above factors will adversely affect the performance and repeatability of a player's shot. | Device for shaping a cue stick tip, including a body, a scuffer mounted at one end of the body and a coiner mounted at the other end of the body. The scuffer is for rough cutting the tip, especially a new tip or badly worn tip, to impart a desired overall shape to the tip, and the coiner reforms the tip which has been distorted and dimpled as a result of repeated cue tip-ball contact to remove the dimples and impart a smooth and uniform exterior contour to the tip. | 1 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to product containers having lids, and more particularly to a device for securing a lid on a container utilizing a handle of the container and to a method for securing a lid on a container.
2. Description of the Related Art
Containers are known in the art that have a lid closing off an opening in the top surface. One common type of lid is held in place only by friction and slight expansion and contraction of the material at the junction between the lid and container. Such containers are commonly known and utilized for holding paint, stains, varnishes and the like. Many of the larger size containers for these types of products also have a separate handle or rail of wire carried on the container. The handle is secured at opposite ends to sides of the container and extends upward and curves over the top of the lid and the container.
It is also common for many of these products to require a vigorous agitation or mixing process prior to use. Because the lids of these containers are typically held on only by friction and lateral pressure between the lid and the container, the mixing process often loosens the lid. Sometimes the lid pops off during the agitation process and sometimes the lid comes off only after the container is removed from the agitator.
Many existing agitators and mixers for paint cans and the like do not include a specific mechanism for holding a lid on the container and if they do, the holder is not intended to press the lid onto the opening of the container during agitation.
Therefore, one problem with these types of containers and the mixing process is that paint or other product will be spilled and lost when the lid pops off the container. Alternatively, the product will splatter within the mixer during the agitation process. Another problem is that if the lid does not pop off during the mixing process, it may come off when the container is removed from the mixer. Again, product will spill resulting in a loss of the product. A spill may further result in damage to objects in the environment surrounding the mixer such as carpeting, painted walls, furniture, clothing and the like.
SUMMARY OF THE INVENTION
One object of the present invention is to provide a device that can securely hold the lid on a container that does not require any elaborate fastening or clamping elements. Another object of the present invention is to provide a device for holding a lid on the container that is very simple in construction and easy to manufacture. A further object of the present invention is to provide a device for holding a lid on a container that is simple to install on a container utilizing only a top surface of the lid and a handle of the container. A still further object of the present invention is to provide a device for holding a lid on a container wherein the container and the device as attached can be placed in a machine that agitates contents held within the container. A further object of the present invention is to provide a device that holds a lid on a container via applied pressure to the lid to prevent the lid from popping of the container.: Another object of the present invention is to provide a device for holding a lid on a container such as paint cans that is sturdy, durable, reliable and requires minimum care and yet is, available for repeated use.
To accomplish these and other objects, features and advantages of the present invention, one embodiment of such a device includes a base having an upper surface and a lower surface. An expander means of the device contacts both the base and part of the container. The expander means can be arranged for applying a downward pressure to the base for pressing the lid against the container.
In one embodiment, the expander means has a base contacting portion for contacting the base and a container engaging portion for connecting to part of the container. In one embodiment, the container engaging portion is a clamp having at least two opposed clamping elements for hooking under and interlocking with a portion of the container. The base contacting portion is an expander disposed between the clamp and the upper surface of the base for adjusting a distance between the base and the clamp.
In one embodiment, the clamping elements are for hooking under a lip of the container. In another embodiment, the clamping elements are for hooking under handle attachment ears of the container.
In one embodiment, the expander is an over-center toggle extending upward from the upper surface of the base. In another embodiment, the expander is a threaded rod extending upward from the upper surface of the base and that is threaded to the clamp.
In one embodiment, a stop section projects upward from the upper surface of the base and has a convex top surface and an apex. At least one handle receiving depression is formed in the top surface of the stop section. The at least one depression is formed generally for receiving and retaining therein a handle of a container.
In one embodiment, the stop section is generally planar and is arranged perpendicular to the base and wherein the top surface is a top edge of the planar stop section. In one embodiment, the at least one depression is a semi-circular groove having an axis arranged transversely to the top edge of the stop section.
In one embodiment, the at least one depression has a contour that compliments a shape of the handle of the container.
In one embodiment, the base and the stop section are each a separate component attached to one another. In one embodiment, the base includes a slot formed through the base and the stop section includes a depending tab received in the slot wherein the stop section is adhered to the base.
In one embodiment, the base and the stop section are each formed of a material selected from at least plastics, thermoplastics, composites, and elastomeric resins.
In one embodiment, the base and stop section are formed as an integral one-piece unitary structure.
In one embodiment, the stop section includes at least two handle receiving depressions formed in the top surface. A first depression is formed near the apex and a second depression is formed spaced from the first depression and disposed further from the apex.
In one embodiment, the top surface of the stop section is a domed surface disposed above the base. In one embodiment, the domed surface has at least a first and a second depression, each an elongate, semi-circular cross section groove formed in the domed surface with each groove having a longitudinal axis. In one embodiment, the first groove passes generally over the apex of the domed surface and the second groove passes over the domed surface offset relative to the apex.
In one embodiment, the longitudinal axis of the first groove is arranged generally perpendicular to the longitudinal axis of the second groove.
In one embodiment, the base is generally circular and has a generally planar lower surface for abutting against a generally flat lid of the container.
In one embodiment, the top surface of the planar stop section is generally semi-circular. In one embodiment, the domed top surface of the stop section is generally semi-spherical.
In another embodiment of the present invention, a method of securely holding a lid on a container includes first providing a device as described above having a base and an expander means in contact with the base. The lower surface of the base of the device is placed against the lid of the container with the upper surface of the base facing the handle. The expander means then engages a portion of the container to force the base downward against the lid. The expander means is then further forced into contact with the base to securely hold the lid against the container.
In one embodiment of the: method, the container and the attached device are placed in a machine for agitating contents held within the container.
BRIEF DESCRIPTION OF THE DRAWINGS
The following drawing figures illustrate a number of embodiments of the present invention. Like reference numerals provided in the drawings represent like components between embodiments of the invention and, wherein:
FIG. 1 illustrates a perspective view of a device constructed in accordance with the present invention installed on a paint can;
FIG. 2 illustrates a side view of the device shown in FIG. 1;
FIG. 3 illustrates a top view of the device of FIG. 1;
FIG. 4 illustrates a perspective view of an alternative embodiment of a device constructed in accordance with the present invention;
FIG. 5 illustrates a top view of the device shown in FIG. 4;
FIG. 6 illustrates a side view of the device shown in FIG. 4;
FIG. 7 illustrates a partial front view of an alternative embodiment of a device constructed in accordance with the present invention;
FIG. 8A illustrates a partial front view of another alternative embodiment of a device constructed in accordance with the present inventions;
FIG. 8B illustrates a partial view of a portion of the device of FIG. 7 attached in an alternative manner to a container; and
FIG. 9 illustrates the paint can and device shown in FIG. 1 installed in a holder of an agitation machine.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present invention is directed to a device for holding a lid on a container such as a paint can. The device utilizes only a portion of the container and a top surface of the lid to hold the lid on the container. The device is useful for sealing storage containers such as paint cans. but is more importantly suited for holding a lid on a container when the container undergoes violent movement such as when transporting the container or when agitating or shaking the contents within the container.
The device of the invention utilizes a plate that rests on the lid of the container and also has a means for applying compression to the plate and hence to the lid of the container. The means for pressing the plate against the lid utilizes a portion of the container in order to apply such pressure. Several embodiments of the present invention are disclosed wherein two embodiments utilize a handle of a container in order to apply pressure to the lid through the plate or base and two additional embodiments utilize a lip of the container where the handle-retaining ears of the container in order to apply pressure through the base or plate to the lid.
Referring now to the drawings, FIG. 1 illustrates one embodiment of a lid securing device 10 constructed in accordance with the present invention and installed on a paint can 12 . The device 10 is forced between a top surface 14 (see FIGS. 7 or 9 ) of a lid 16 of the container 12 and a handle 18 of the container. The installation method and other aspects of the invention are described in more detail below.
The device 10 of the invention includes a base or plate 20 with an upper surface 22 and a lower surface 24 . In the present embodiment, the base 20 is essentially a circle of material having a diameter and a thickness. The circumference and diameter of the base 20 preferably generally follows the contour of the lid 16 , in this case a circular contour. The thickness of the material is preferably such that the base will provide a relatively rigid abutting surface against the lid when the device 10 is used. In the present embodiment, the base 20 is also generally planar on both its upper and lower surfaces. It will be apparent to those skilled in the art that the base 20 can take on other shapes and sizes without departing from the spirit and scope of the invention. It is also apparent that the upper and lower surfaces 22 and 24 , respectively, can have other surface contours than the planar contours illustrated, depending on the shape and contour of the container. The size and shape of the base 20 will more evenly and efficiently distribute a compression force against the lid 16 if it generally matches the lid.
A stop section 26 projects upward from the upper surface 22 of the base 20 . The stop section 26 has a top surface 28 that is convex and has an apex 30 at or near the mid-point of the top surface. In this embodiment, the stop section is also in the form of a planar element having a thickness that is in generally similar to that of the base. The stop section 26 of this embodiment includes a stalk portion 32 that supports a cap portion 34 above the base 20 . The cap portion 34 defines the top surface 28 in this embodiment and the stalk portion 32 simply supports the cap.
The stalk 32 and cap 34 a e formed as an integral, one-piece unit but could easily be formed as two or more separate components assembled to one another. Regardless of the construction, the top surface 28 of the stop section 26 includes at least one depression 36 formed in the top surface. In the embodiment of FIGS. 1-3, the top edge of the planar stop section 26 defines the top surface. The first depression 36 is formed as a notch or cut-out defining a transverse groove in the top surface 28 . The groove or depression 36 has a longitudinal axis that is perpendicular to the plane of the stop section 26 . The contour of the depression 36 can vary considerably within the scope of the present invention. In the present embodiment, the handle 18 is illustrated as having a sleeve 37 over part of the handle where the sleeve has a generally circular cross section. The depression 36 also includes a circular cross section that corresponds to the shape of the handle and sleeve. As will be apparent to those skilled in the art, other handle and depression configurations and constructions can be utilized and yet fall within the scope of the present invention.
A second depression 38 is also illustrated in FIGS. 1-3 having essentially the same characteristics of that described for the depression 36 . However, the depression 38 is disposed spaced from the first depression 36 and further from the apex.
The device 10 is utilized to securely hold the lid on the container by pressure applied by wedging the device between the handle 18 and the lid 16 . The device 10 can be constructed and designed to accommodate more than one container size and handle configuration and therefore can include more than one depression. The device however will be designed to accommodate a maximum distance for at least one specific container size between the handle and lid. Therefore, the first depression 36 is designed to accommodate the maximum size container for the device 10 . Therefore, the first depression 36 is preferably positioned at or near the apex 30 of the convex top surface 28 . The second depression 38 is then preferably positioned spaced from the first depression 36 and also spaced from the apex 30 a greater distance than the first depression. The second depression is intended to accommodate a smaller container that has a shorter distance between the lid and the uppermost point of the handle.
As will be evident to those skilled in the art, the top surface 28 of the stop section 26 can be provided with more than two depressions and can accommodate more than one type of container, depending upon the intended use of the device 10 . It will also be apparent that the top surface 28 need not be a smooth arcuate surface as is illustrated in FIGS. 1-3, but can alternatively be a multiple contoured surface providing ledges or odd-shaped depressions into which a handle can rest when the device is used. The device 10 can be designed to fit various container sizes and handle and lid configurations.
The parts of the device 10 as illustrated in FIGS. 1-3 can be punched or cut from a sheet of material, thus utilizing a minimum of raw material. This is because the components of the device are relatively thin arid planar in construction and have the same thickness. The stop section 26 and the base 20 can be fabricated as two separate components and assembled to one another as illustrated in FIG. 2 . In this embodiment, the base 20 has a slot 40 formed near the center of the base for receiving a tab 42 depending from a bottom edge 44 of the stop section 26 . The tab 42 is received in the slot 40 and suitably adhered to the base 20 . Alternatively, the stop section 26 and the base 20 can be integrally molded or cast as a one-piece unitary structure having no separation between the components. In either embodiment, the materials used to fabricate the device 10 can vary considerably but may include at least steel, other metals, plastics, thermoplastics, plastic composites, elastomer or elastomeric resins and other relatively strong materials. Virtually any material can be utilized to fabricate the device 10 of the invention.
The device 10 is very simple in construction and easy to manufacture and requires minimum raw material and relatively inexpensive tooling in order to produce. The device 10 may be suitable for many applications. However, the thin cross section of the stop section and the flexible nature of some types of handles 18 may result in handles being bent or destroyed when the device 10 is used. Therefore, a more sturdy device construction may be necessary for some applications where the device also more evenly distributes a load to the handle 18 .
With that in mind, FIGS. 4-6 illustrate one possible alternative embodiment of a lid securing device 50 . The device 50 includes a base 20 similar to that described previously for the device 10 . The device 50 also includes a stop section 52 projecting upward from the upper surface 22 of the base 20 . The stop section 52 in the present embodiment includes a stalk portion 54 that is illustrated having a cylindrical cross section, although the stalk in this embodiment could be planar similar to the stalk portion 32 described previously, or could have numerous other shapes and constructions. A cap portion 56 is disposed on the stalk portion 54 and also includes a top surface 58 that is convex in shape and has an apex 60 . However, in this embodiment, the top surface 58 is a domed surface having a generally spherical contour. The top surface 58 in this embodiment also includes a first depression 62 in the form of an elongate groove formed into the top surface and passing over or at least near the apex 60 of the stop section 52 . The first depression 62 also includes a longitudinal axis and a contour that compliments the shape and contour of a handle 18 . The contour and size of the first depression can vary considerably and yet fall within the scope of the present invention. The first depression 62 is again disposed at or near the apex of the top surface 58 in order to accommodate a larger distance between a handle and a container lid for a maximum size container. A second depression 64 is also provided in the top surface 58 having generally the same elongate groove construction and a longitudinal axis and contour. The second depression is disposed offset relative to the apex so that it has a reduced height between the top surface 58 and the lower surface 24 of the base to accommodate containers having a shorter distance between a handle and a lid.
In the present embodiment, the first depression 62 is illustrated as being arranged perpendicular relative to the second depression 64 . However, virtually any other orientation of the axes of the two grooves or depressions 62 and 64 can be utilized.
In this embodiment, the curved spherical surface 58 provides a greater surface area on which the handle 18 of a container can rest. This larger surface area permits the handle to exert force downward from the base 20 into the lid 16 over a larger surface area to assist in preventing the handle 18 from becoming bent when used.
As will be evident to those skilled in the art, the depressions 62 and 64 including their size and contour, can vary considerably and yet fall within the scope of the present invention. Additionally, more than two depressions and more than one type of depression can be provided in the top surface 58 to accommodate a variety of different container sizes and types. The shape of the stalk portion 54 can also vary considerably and yet function according to the present invention. The stalk portion 54 and cap portion 56 can be formed as an integral unit or can be formed as two or more separate components and subsequently attached by any suitable means.
To use the device 10 or 50 of the present invention, a user simply places the lower surface 24 of the base 20 on the top surface 14 of the lid 16 of the container or paint can 12 . The depressions must be oriented so that the handle is lowered from its upright position, illustrated by the arrow “A” in FIG. 1, and located on the same side or facing the depressions. This is so that the handle does not need to pass completely over the apex of the device when installed which would unnecessarily stretch and perhaps damage the handle. The handle 18 is then pivoted toward its uppermost position and eventually rides along the top surface of the device. The handle will begin to ride against the top surface and press downward on the device so that the base 20 presses against the lid. If one continues to move the handle toward the apex, the handle will pop into the next adjacent depression. The handle should easily pass any depressions that are located too far from the apex and too low for the size of the handle. The design of the top surface contour can accommodate this function. Once the handle 18 snaps into the appropriate depression, the shape and contour of the depression will hold the handle in place. The pressure applied by the handle 18 to the base 20 of the device 10 or 50 will securely hold the lid 16 against the container 12 .
FIGS. 7, 8 A, and 8 B illustrate additional embodiments of a lid securing device of the present invention. FIG. 7 illustrates a device 70 mounted to the paint can 12 . The device 70 includes a base 20 having a bottom surface 22 and a top surface 24 and is essentially identical in construction to the base 20 described in previous embodiments. The device 70 also includes an upstanding rod 72 extending upward from the upper surface 24 . The upstanding rod has an upper end with a gripping handle 74 carried thereon. A C-shaped clamp 76 is bisected by the rod 72 and extends radially therefrom. The clamp 76 is carried on the rod 72 by a threaded collar 78 that includes internal threads that correspond to external threads 80 on the rod. The rod 72 and collar 78 can therefore rotate relative to one another moving the collar and hence the clamp 76 along the rod. The lower end of the rod includes a ball and socket connection 82 to the base 20 securely holding the rod to the base and yet permitting the rod 72 to rotate relative to the base. The clamp 76 includes a pair of downwardly depending claws 84 that are designed and sized to hook beneath a lip 86 of the top end of the can 12 via fingers on the claws.
To utilize the device 70 , the bottom surface 22 of the base 20 is placed against the lid 16 of the container 12 . The fingers 88 are initially below the lip 86 . The grip or handle 74 is then rotated in order to turn the rod 72 relative to the collar 78 . By doing so, the clamp 76 is drawn upward so that the fingers 88 contact the lip 86 . The grip or handle 74 is then further rotated which will force the clamp 76 upward relative to the rod 72 . Because the fingers 88 are interlocked with the lip 86 , the base 20 will then press down on the lid 16 securing the lid to the can 12 .
FIG. 8A illustrates another alternative embodiment of a device 90 constructed in accordance with another embodiment of the invention. The device 90 also includes a plate or base 20 for resting against a lid 16 of a container 12 . The top surface 24 of the base includes an upstanding bracket 92 connected to a lower pivot 94 of an over-center toggle 96 . The toggle 96 includes an upper pivot 98 carried centrally along a C-shaped clamp 76 constructed essentially identical to that described in the previous embodiment. The toggle 96 also includes a central pivot 100 separating the toggle into two toggle elements 102 and 104 .
In one direction, indicated in FIG. 8A by the arrow B, the toggle 96 is free to pivot about the central pivot 100 so that the base 20 can lift and lower relative to the bracket. When the toggle is moved past the center position in the direction of the arrow C wherein all three pivots 94 , 98 and 100 are linearly aligned, the toggle passes just beyond the over-center condition and then is prevented from moving any further by a suitable stop. In the over-center condition, the bracket or clamp 76 is forced upward drawing the fingers 88 into locking engagement with the lip 86 of the can 12 and forcing the base 20 downward against the lid 16 . A stop or lock means is carried on the toggle 96 in order to prevent the toggle from further moving in the direction of the arrow C thus locking the lid 16 against the can 12 .
FIG. 8B illustrates an alternative embodiment for connecting the clamp 76 to the can 12 . In this embodiment, the fingers 88 do not engage a lip of the can, but instead engage a retaining ear 110 of the can. The retaining ears 110 secure the handle 18 to the container such as the paint can 12 . The particular design of the fingers 88 and ears 110 can vary considerably within the scope and spirit of the present invention so long as the clamp 76 is capable of interlocking with the ears 110 in order to perform the intended function of the invention.
FIG. 9 illustrates one important use of the present invention. A container 12 including a device 10 attached thereto can be installed into a mixing machine 170 or agitator such as a paint mixer. A typical mixing machine 170 has a two part container holder 172 with a parting line 173 dividing the holder 172 into two sections 174 and 176 . The two sections can receive the container therein prior to closing and then the two sections can be closed to abut one another. A typical holder 172 has a bottom surface 177 or at least a portion of a bottom surface against which the bottom of the container will rest. A top in-turned lip 179 of the holder 172 overlaps a portion of the top surface of the container. Sometimes this top lip 179 will overlap a portion of the lid 16 as well and at least prevent the lid from flying off the container during the mixing process. Sometimes the lip will cover nearly the entire lid of the container. However, these mixing machines 170 do not typically provide downward pressure on to the lid 16 of the paint can or container 12 . The two sections 172 and 174 of the holder 172 also provide slots or cut-outs 180 to accommodate the handle 18 as well as the attachment ears 110 .
If the lip 179 does bear against the lid, the lid will at least not release during the mixing process, but the lid is not held securely and pressed downward into and against the container. When the mixing process is complete, it often occurs that the container is removed and the lid then pops off, releasing the contents of the container. This is because during the mixing process, the contents within the container continually are forced against the lid which at least partially breaks the seal between the lid and container. If the lip 178 does not bear against the lid, the lid oftentimes will release from the container during the mixing process and permit the contents within the container to enter into the mixing machine 170 . The devices of the invention prevent each of these occurrences from happening and yet do so at minimum expense to a user.
Though specific embodiments of the present invention are described herein, the invention is not intended to be so limited. Modifications and changes can be made to the described embodiments and yet fall within the scope and spirit of the present invention. The invention is intended to be limited only by the scope and spirit of the appended claims. | A device and method are provided for securely holding a lid on a container. The device includes a base having an upper surface and a lower surface. An expanding means projects upward from the upper surface of the base. The expanding means contacts both the base and part of the container and can be arranged for applying a downward pressure to the base:for pressing the lid against the container. A method utilizing the device includes the step of placing the lower surface of the base against the lid of a container. A portion of the expander means then engages a portion of the container. The lid is then pressed against the container by forcing the base against the lid using the expander means. | 1 |
RELATED PATENT APPLICATIONS
This patent application is related to U.S. patent application Ser. No. 13/168,047, entitled “Curable composition comprising a di-isoimide, method of curing, and the cured composition so formed;” U.S. patent application Ser. No. 13/168,062, entitled “Laminate comprising curable epoxy film layer comprising a di-isoimide and process for preparing same;” U.S. patent application Ser. No. 13/168,024, entitled “Di-isoimide Composition;” and, U.S. patent application Ser. No. 13/168,081, entitled “Process for Preparing a Di-Isoimide Composition.”
FIELD OF THE INVENTION
The present invention deals with a flexible printed wiring board in the form of a printed wiring board wherein the conductive elements are fully encapsulated by an epoxy adhesive comprising a novel aromatic di-isoimide chemical compound.
BACKGROUND OF THE INVENTION
Epoxy compositions are widely used in many applications including, among others, the electronics industry. In some applications they are blended with rubber to provide enhanced flexibility, toughness, and adhesive strength. One such application is as a flexible cover layer for flexible printed wiring boards.
While epoxies offer many desirable properties, they are known to be undesirably flammable, often requiring the addition of a flame retardant to a curable epoxy formulation in order to meet fire resistance standards. In addition, it is desirable to have a curable epoxy composition with as long a shelf life as possible. One approach to achieving long shelf-life is to prepare a so-called latent curing catalyst or cross-linking agent (curing agent). A latent catalyst or curing agent could be inactive at room temperature but thermally activated at a temperature well above room temperature. For practical reasons, it is desirable for uncured compositions to remain stable at temperatures up to 40 or 50° C. Thus a latent catalyst or curing agent activated at a temperature above 50° C. but below a temperature that will degrade the epoxy or electronic circuit elements is highly desirable in the art. A catalyst or curing agent that further obviates the need for a flame retardant additive would be so much the better for the properties of the resultant composition.
SUMMARY OF THE INVENTION
The composition of the present invention provides a curing catalyst and cross-linking agent suitable for use in a curable epoxy composition, a curable epoxy composition prepared therewith, a cured composition prepared therefrom, a film or sheet coated with the curable composition, and an encapsulated printed wiring board comprising the cured composition.
In one aspect, the present invention provides a di-isoimide composition represented by Structure I
wherein R 1 is H, halogen, hydrocarbyl, hydrocarbyloxy, hydrocarbylthio, amido, sulfonamido, cyclic amino, acyl, morpholino, piperidino, or NR′R″ where R′ and R″ are independently H, alkyl or aromatic, substituted or unsubstituted.
In another aspect, the invention provides a first process for preparing a di-isoimide composition represented by the Structure I, the process comprising mixing, at a temperature in the range of −10 to 160° C., in a first solvent pyromellitic dianhydride (PMDA) with a substituted or unsubstituted di-amino triazine represented by the Structure II
wherein R 1 is H, halogen, hydrocarbyl, hydrocarbyloxy, hydrocarbylthio, amido, sulfonamido, cyclic amino, acyl, morpholino, piperidino, or NR′R″ where R′ and R″ are independently H, alkyl or aromatic, substituted or unsubstituted.
In a further aspect, the present invention provides a curable composition comprising a solvent having mixed therewithin an epoxy and a di-isoimide composition represented by Structure I
wherein R 1 is H, halogen, hydrocarbyl, hydrocarbyloxy, hydrocarbylthio, amido, sulfonamido, cyclic amino, acyl, morpholino, piperidino, or NR′R″ where R′ and R″ are independently H, alkyl or aromatic, substituted or unsubstituted.
In a further aspect, the present invention provides a second process comprising heating the curable composition hereof to a temperature in the range of 100 to 250° C. for a period of time in the range of 30 seconds to 5 hours, thereby forming the corresponding cured composition.
In another aspect, the present invention is directed to a laminated article comprising a substrate and a coating deposited thereupon wherein said substrate is a polymeric sheet or film and said coating comprises a curable composition comprising a second solvent having mixed therewithin an epoxy and a di-isoimide composition represented by Structure I.
In a further aspect, the present invention is directed to a printed wiring board comprising in order a first layer of a first dielectric substrate, a second layer of one or more discrete electrically conductive pathways disposed upon said first dielectric substrate, a third layer of an adhesively bonding layer in adhesive contact with said discrete electrically conductive pathways, and a fourth layer of a second, flexible, dielectric substrate, said adhesively bonding layer comprising a curable composition comprising a second solvent having mixed therewithin an epoxy and a di-isoimide composition represented by Structure I.
In another aspect, the present invention provides a process for preparing an encapsulated printed wiring board, the process comprising adhesively contacting the coated surface of a laminated article having a surface with a coating disposed thereupon to at least a portion of the discrete conductive pathways disposed upon a dielectric substrate thereby forming a multilayer article; and, applying pressure to the printed wiring board so formed at a temperature in the range of 100 to 250° C. for a period of time in the range of 30 seconds to 5 hours, thereby forming an encapsulated printed wiring board; wherein said printed wiring board comprises in order a first layer of a first dielectric substrate, a second layer of one or more discrete electrically conductive pathways disposed upon said first dielectric substrate, a third layer of an adhesively bonding layer in adhesive contact with said discrete electrically conducting pathways, and a fourth layer of a second, flexible, dielectric substrate, said adhesively bonding layer comprising a curable composition comprising a second solvent having mixed therewithin an epoxy and a di-isoimide composition represented by Structure I.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a schematic representation of the process hereof for creating the printed wiring board hereof, as described in Example 12.
DETAILED DESCRIPTION OF THE INVENTION
The term “epoxy” refers to a polymeric, generally an oligomeric, chemical comprising epoxide groups. A cross-linking agent suitable for use in the processes disclosed herein is a multifunctional molecule reactive with epoxide groups. The cross-linked reaction product thereof is the reaction product formed when the cross-linking agent reacts with the epoxide or other group in the epoxy molecule. The term “epoxy” is conventionally used to refer to the uncured resin that contains epoxide groups. With such usage, once cured, the epoxy resin is no longer actually an epoxy. However, reference to epoxy herein in the context of the cured material shall be understood to refer to the cured material. The term “cured epoxy” shall be understood to mean the reaction product of an epoxy as defined herein and a curing agent as defined herein.
The term “cured” refers to an epoxy composition that has undergone substantial cross-linking, the word “substantial” indicating an amount of cross-linking of 75% to 100% of the available cure sites in the epoxy. Preferably more than 90% of the available cure sites are cross-linked in a “fully cured” epoxy composition. The term “uncured” refers to an epoxy composition when it has undergone little cross-linking. The terms “cured” and “uncured” shall be understood to be functional terms. An uncured epoxy composition is characterized by solubility in organic solvents and the ability to undergo plastic flow under ambient conditions. A cured epoxy composition suitable for the practice of the invention is characterized by insolubility in organic solvents and the absence of plastic flow under ambient conditions. It is well-known in the art that some of the available cure sites in an uncured epoxy composition could be cross-linked and some of the available cure sites in a cured epoxy composition could remain uncross-linked. In neither case, however, are the distinguishing properties of the respective compositions significantly affected.
The art also distinguishes a partially cured epoxy composition known as a “B-stage” material. The B-stage material may contain up to 10% by weight of solvent, and exhibits properties intermediate between the substantially cured and the uncured state.
For the purposes of the present invention the term “curable composition” shall refer to a composition that comprises all the elements necessary for producing a “cured” composition, but that has not yet undergone the “curing process” and is therefore not yet cured. The curable composition is readily deformable and processible, the cured composition is not. The terms “curable” and “cured” are similar in meaning, respectively, to the terms “crosslinkable” and “crosslinked.”
While the invention is not limited thereto, it is believed that the cure reaction of an epoxy with the di-isoimide hereof is mostly a reaction of an amine group of the di-isoimide to open the oxirane ring (or epoxy group, as it is often referred to) resulting in a nitrogen carbon bond, and an alkyl hydroxyl group. So in the above instance, the di-isoimide serves as a cross-linking agent. When, for example, a phenolic novolac is also present, the oxirane ring opening reaction is effected primarily by the reaction of the phenol hydroxyl group of the novolac with the oxirane ring, thereby creating an oxygen-carbon bond and an alkyl hydroxyl group. When a more active cross-linking agent, such as the phenol is not present, the di-isoimide serves as both cross-linking agent and a catalyst.
The terms “film” and “sheet” refer to planar shaped articles having a large length and width relative to thickness. Films and sheets differ only in thickness. Sheets are typically defined in the art as characterized by a thickness of 250 micrometers or greater, while films are defined in the art as characterized by a thickness less than 250 micrometers. As used herein, the term “film” encompasses coatings disposed upon a surface.
The term “discrete conductive pathway” as used herein refers to an electrically conductive pathway disposed upon a dielectric substrate in the form of a film or sheet which leads from one point to another on the plane thereof, or through the plane from one side to the other.
There are several terms that are repeated throughout this invention that are described in detail only upon the first mention thereof. However, in order to avoid prolixity the descriptions of the term are not repeated when the term reappears further on in the text. It shall be understood for the purposes of the present invention that when a term is repeated in the text hereof, the description and meaning of that term is unchanged from and the same as that provided for the term upon its first mention. For example the term “di-isoimide composition represented by Structure I” shall be understood each time it appears to encompass all the possible embodiments recited with respect to Structure I upon its first appearance in the text. For another example, the term “second solvent” shall be understood to refer to the same set of solvents described for the “second solvent” at the first appearance of the term in the text.
For the purposes of this invention, the term “room temperature” is employed to refer to ambient laboratory conditions. As a term of art, “room temperature” is normally taken to mean about 23° C., encompassing temperatures ranging from about 20° C. to about 30° C.
The term “printed wiring board” (PWB) shall refer to a dielectric substrate layer having disposed thereupon a plurality of discrete conductive pathways. The substrate is a sheet or film. In one embodiment of the invention the dielectric substrate is a polyimide film. In a further embodiment, the polyimide film has a thickness of 5-75 micrometers. In one embodiment the discrete conductive pathways are copper.
PWBs suitable for the practice of the present invention can be prepared by well-known and wide-spread practices in the art. Briefly, a suitable PWB can be prepared by a process comprising laminating a copper foil to a dielectric film or sheet using a combination of an adhesive layer, often an epoxy, and the application of heat and pressure. To obtain high resolution circuit lines (≦125 micrometers in width) photoresists are applied to the copper surface. A photoresist is a light-sensitive organic material that when subject to imagewise exposure an engraved pattern results when the photoresist is developed and the surface etched. In a suitable PWB, the image is in the form of a plurality of discreet conductive pathways upon the surface of the dielectric film or sheet.
A photoresist can either be applied as a liquid and dried, or laminated in the form, for example, of polymeric film deposited on a polyester release film. When liquid coating is employed, care must be employed to ensure a uniform thickness. When exposed to light, typically ultraviolet radiation, a photoresist undergoes photopolymerization, thereby altering the solubility thereof in a “developer” chemical. Negative photoresists typically consist of a mixture of acrylate monomers, a polymeric binder, and a photoinitiator. Upon imagewise UV exposure through a patterning photomask, the exposed portion of the photoresist polymerizes and becomes insoluble to the developer. Unexposed areas remain soluble and are washed away, leaving the areas of copper representing the conductive pathways protected by the polymerized photoresist during a subsequent etching step that removes the unprotected conductive pathways. After etching, the polymerized photoresist is removed by any convenient technique including dissolution in an appropriate solvent, or surface ablation. Positive photoresists function in the opposite way with UV-exposed areas becoming soluble in the developing solvent. Both positive and negative photoresists are in widespread commercial use. One well-known positive photoresist is the so-called DNQ/novolac photoresist composition.
Any PWB prepared according to the methods of the art is suitable for use in the present invention.
In one aspect, the present invention provides a di-isoimide composition represented by Structure I
wherein R 1 is H, halogen, hydrocarbyl, hydrocarbyloxy, hydrocarbylthio, amido, sulfonamido, cyclic amino, acyl, morpholino, piperidino, or NR′R″ where R′ and R″ are independently H, alkyl or aromatic, substituted or unsubstituted. In one embodiment, R 1 is NH 2 .
In another aspect, the present invention provides a first process that can be used to prepare the composition represented by the Structure I, the first process comprising mixing in a first solvent, at a temperature in the range of −10 to +160° C., PMDA with a di-amino triazine represented by the Structure II
wherein R 1 is H, halogen, hydrocarbyl, hydrocarbyloxy, hydrocarbylthio, amido, sulfonamido, cyclic amino, acyl, morpholino, piperidino, or NR′R″ where R′ and R″ are independently H, alkyl or aromatic, substituted or unsubstituted.
In one embodiment, R 1 is NH 2 .
Suitable first solvents include but are not limited to polar/aprotic solvents characterized by a dipole moment in the range of 1.5 to 3.5 D. While the reaction between the aminoazine and PMDA takes place in solution, full miscibility of the reactants in the solvent is not necessary. Even limited solubility will permit the reaction to proceed, with additional reactants dissolving as they are consumed in the reaction. Suitable solvents include but are not limited to acetone, methyl ethyl ketone (MEK), methyl isobutyl ketone, ethyl propionate, ethyl-3-ethoxy propionate, cyclohexanone, and mixtures thereof. Mixtures thereof with small amounts (for example, less than 30% by weight) of non-polar solvents such as benzene are also suitable. In one embodiment, the solvent is cyclohexanone.
When the dipole moment is below 1.5 D, solubility of melamine, already low, becomes so low that the reaction can take weeks to go to completion. When the dipole moment of the solvent exceeds 3.5 D the rate of the reaction converting the di-isoimide to di-imide can proceed at an inconveniently rapid rate, causing excessive loss of the desired di-isoimide.
According to the first process of the invention, PMDA and a suitable diamino triazine, substituted or unsubstituted, as described supra, are combined in the presence of a suitable first solvent, and allowed to react. The reaction temperature can be in the range of −10 to +160° C. The yield of di-imide increases with increasing temperature, at the expense of the di-isoimide. While this invention is directed to the preparation of and the advantageous use of the di-isoimide, the presence of some di-imide mixed in with the di-isoimide does not necessarily have any particularly negative impact. In some instances, it could be advantageous to use a higher reaction temperature which results in lower selectivity but higher reaction rate.
In general, higher reaction temperature corresponds to faster reaction. Selectivity depends on temperature and the specific choices of dianhydride, triazine, and solvent. For example PMDA and melamine in cyclohexanone produce pure isoimide at 25° C., almost pure isoimide at 50° C., and produce about 80% isoimide at reflux (˜155° C.). PMDA and melamine react faster in N,N-dimethyl formamide (DMF) than in cyclohexanone at the same temperature but the reaction continues on to form imide from a di-isoimide intermediate if the reaction is not stopped in time.
In one embodiment, the reaction temperature is in the range of room temperature to 100° C. In a further embodiment, the reaction temperature is in the range of room temperature to 50° C.
The first process hereof does not require a water scavenger (such as trifluoroacetic acid) in order to provide the desired di-isoimide as represented by Structure I. It is highly preferred in the first process hereof to omit any water scavenger, in order to avoid having subsequently to remove the water scavenger after reaction is complete.
It is observed in the practice of the invention that the di-isoimide hereof is more soluble than the analogous imide in relatively mild, low boiling point solvents such as cyclohexanone and MEK. Much stronger high boiling point solvents, such as dimethyl acetamide (DMAC) or n-methylpyrrolidone (NMP), are required to dissolve the imide. This feature of the di-isoimide hereof is of considerable importance in the formulation of epoxies with practical commercial applicability. It is difficult to remove high boiling point solvents without also initiating the epoxy cure. For adhesive applications, particularly highly critical applications such as the fabrication of encapsulated PWBs as described herein, it is essential to have the solvent removed completely since the adhesive is sealed between the two surfaces it is binding together, and there is no place to which solvent can escape without causing bubbles and voids in the finished product. Bubbles and voids adversely affect the uniformity of the dielectric constant.
Maintaining a high degree of mixing during reaction is important for achieving full conversion of the reactants into the di-isoimide product. For example, melamine is of very limited solubility in the suitable solvents. PMDA is also only poorly soluble. In order to achieve high conversion within a commercially viable time frame, it is necessary to maintain good intermixing of the reactants with each other and with the solvent. While the invention is not thereby limited, it is believed that the solution equilibrium for the reactants causes small amounts of reactants to dissolve, and that the thus dissolved reactants react to form a precipitate of the di-isoimide, thereby causing additional reactants to dissolve. This process is believed to continue until the reactants are exhausted, and conversion is quantitative as indicated by the disappearance of the reactant peaks in the infra-red (IR) spectrograph of the solvent dispersion.
Suitable mixing can be achieved using mechanical stirring such as magnetic stirring. A satisfactory state of mixing is one wherein the dispersion of reactants (and product) in the solvent has a uniform appearance with no regions of stagnant solids. It is preferred to stir to maintain a uniform appearance throughout the duration of the reaction.
It is found in the practice of the invention, as herein exemplified infra in Examples 7 and 8, performing the first process hereof in the presence of a rubber compound containing carboxylic acid groups in solution causes the reaction to achieve a higher rate of conversion than the same reaction when run without the rubber.
In a further aspect, the present invention provides a curable composition comprising a second solvent having mixed therewithin an epoxy and a di-isoimide composition represented by Structure I. In one embodiment, the second solvent is the same as the first solvent.
Solvents suitable for use as the second solvent include but are not limited to acetone, MEK, cyclohexanone, pentanone, dioxolane, tetrahydrofuran, glycol ethers, propylene glycol methyl ether acetate (PMA), N-methylpyrrolidone, N,N-dimethylacetamide, DMF, dimethyl sulfoxide, N,N-diethylacetamide, N,N-diethylformamide, N,N-dimethylmethoxyacetamide. Preferred solvents are MEK, cyclohexanone, PMA, and DMF. Mixtures of solvents are also suitable.
Referring to Structure I, in one embodiment, R 1 is NH 2 .
Suitable epoxies for the curable composition hereof are epoxies comprising an average of at least two epoxide groups per polymer chain. Suitable epoxies include but are not limited to polyfunctional epoxy glycidyl ethers of polyphenol compounds, polyfunctional epoxy glycidyl ethers of novolak resins, alicyclic epoxy resins, aliphatic epoxy resins, heterocyclic epoxy resins, glycidyl ester epoxy resins, glycidylamine epoxy resins, and glycidylated halogenated phenol epoxy resins. Preferred epoxies include epoxy novolacs, biphenol epoxy, bisphenol-A epoxy and naphthalene epoxy. Preferred epoxies are oligomers having 1-5 repeat units. Most preferably the epoxy is bisphenol-A or novolac epoxy, especially bisphenol A diglycidyl ether.
Epoxies can be derivatized in any manner described in the art. In particular they can be halogenated, especially by bromine to achieve flame retardancy, or by fluorine.
In one embodiment of the curable composition hereof R 1 is NH 2 ; the solvent is MEK, cyclohexanone, propylene glycol methyl ether acetate, DMF, or a mixture thereof; and, the epoxy is of the bisphenol-A type.
The di-isoimide represented by Structure I can serve both as a curing catalyst and/or as a curing agent in the curable composition hereof. The isoimide moiety reduces the flammability of the cured epoxy (vs. phenolic novolac, which does not have a comparable flame retardant effect) and thus reduces the need for flame retardants. In one embodiment, the curable composition further comprises a curing agent. Any curing agent known in the art can be used in the compositions and processes disclosed herein. Suitable curing agents include organic acid anhydrides and phenols. Monoanhydride curing agents are preferred for ease of handling.
In an alternative embodiment, the curable composition hereof does not include a separate curing agent. It is found in the practice of this embodiment of the invention that the nucleophilic character of the amine group is much reduced by the presence of the triazine ring and the isoimide linkage. It is further found that once one of the amine groups on the ring undergoes reaction, the second amine group becomes still less reactive. Therefore in formulating the curable composition in this embodiment, it is found that satisfactory results are achieved by treating each mole of the di-isoimide of Structure I as representing two equivalents from the standpoint of cross-linking the epoxy. A formulation on that basis that contains a 20% excess in equivalents of epoxy has been found to be satisfactory.
The curable composition hereof can include any and all of the numerous additives commonly incorporated into epoxy formulations in the art. This can include flame retardants, rubber or other tougheners, inorganic particles, plasticizers, surfactants and rheology modifiers.
In one embodiment, the curable composition hereof comprises a low molecular weight liquid epoxy that serves as a dispersion medium for the di-isoimide composition represented by Structure I. Low molecular weight epoxies, such as EPON™ Resin 828, are characterized by equivalent weight of 185-192 g/eq. However, such low molecular weight epoxies are less preferred than the pastier, more viscous, higher molecular weight high performance epoxies that are well-known in the art. Higher molecular weight epoxies, such as EPON™ Resin 1001F, are characterized by equivalent weight of 525-550 g/eq. While the reaction mixture formed from the higher molecular weight epoxies can be heated in order to lower viscosity, it is undesirable to apply heat for that purpose, especially in the presence of a catalyst, because of the risk of causing premature curing. In a highly preferred embodiment a high molecular weight epoxy is dissolved in a second solvent hereof—or, less preferably dispersed therein—into which a solution or dispersion of the di-isoimide composition of Structure I is then dispersed to form the curable composition hereof.
Suitable curing agents are phenol and aromatic anhydrides. The epoxy and the curing agent are mixed in quantities based on their equivalent weights. In the case of phenolic curing agents, 0.3-0.9 equivalent of phenol is preferred for each equivalent of epoxy has been found to be suitable. With anhydride curing agents, 0.4-0.6 equivalent of anhydride is preferred for one equivalent of epoxy.
Suitable phenol curing agents include biphenol, bisphenol A, bisphenol F, tetrabromobisphenol A, dihydroxydiphenyl sulfone, novolacs and other phenolic oligomers obtained by the reaction of above mentioned phenols with formaldehyde. Suitable anhydride curing agents are nadic methyl anhydride, methyl tetrahydrophthalic anhydride and aromatic anhydrides.
Aromatic anhydrides curing agents include but are not limited to aromatic tetracarboxylic acid dianhydrides such as pyromellitic dianhydride, biphenyltetracarboxylic acid dianhydride, benzophenonetetracarboxylic acid dianhydride, oxydiphthalic acid dianhydride, 4,4′-(hexafluoroisopropylidene)diphthalic acid dianhydride, naphthalene tetracarboxylic acid dianhydride, thiophene tetracarboxylic acid dianhydride, 3,4,9,10-perylene tetracarboxylic acid dianhydride, pyrazine tetracarboxylic acid dianhydride, and 3,4,7,8-anthraquinone tetracarboxylic acid dianhydride. Other suitable anhydride curing agents are oligomers or polymers obtained by the copolymerization of maleic anhydride with ethylene, isobutylene, vinyl methyl ether and styrene. Maleic anhydride grafted polybutadiene can also be used as a curing agent.
Suitable tougheners are low molecular weight elastomers or thermolastic polymers and contain functional groups for reaction with epoxy resin. Examples are polybutadienes, polyacrylics, phenoxy resin, polyphenylene ethers, polyphenylene sulfide and polyphenylene sulfone, carboxyl terminated butadiene nitril elastomers (CTBN), epoxy adducts of CTBN, amine terminated butadiene nitril elastomers (ATBN), carboxyl functionalized elastomers, polyol elastomers and amine terminated polyol elastomers. Epoxy adducts of CTBN, CTBN and carboxyl functionalized elastomer are preferred.
In one embodiment, the di-isoimide can be pre-dispersed in the solvent in which it was prepared. In an alternative embodiment, the di-isoimide may be added as particles to the epoxy solution and dispersed therein using mechanical agitation.
In a further aspect, the present invention provides a second process, a process for preparing a cured composition from the curable composition hereof by heating the curable composition to a temperature in the range of 100 to 250° C. for a period of time in the range of 30 seconds to 5 hours. For adhesive applications the solvent needs to be removed completely before curing, as described in the Examples, infra.
The viscosity of the uncured composition can be adjusted by either adding solvent to decrease the viscosity, or by evaporating solvent to increase viscosity. The uncured composition can be poured into a mold, followed by curing, to form a shaped article of any desired shape. One such process known in the art is reaction injection molding. In particular, the composition can be used in forming films or sheets, or coatings. The viscosity of the solution is adjusted as appropriate to the requirements of the particular process. Films, sheets, or coatings are prepared by any process known in the art. Suitable processes include but are not limited to solution casting, spray-coating, spin-coating, or painting. A preferred process is solution casting using a Meyer rod for draw down of the casting solution deposited onto a substrate. The substrate can be treated to improve the wetting and release characteristics of the coating. Solution cast films are generally 10 to 75 micrometers in thickness. The solution casting of a solution/dispersion hereof onto a substrate film or sheet to form a laminated article is further described in the specific embodiments hereof, infra.
In another aspect, the present invention is directed to a laminated article comprising a substrate and a coating adheringly deposited thereupon wherein said substrate is a polymeric sheet or film and said coating comprises a curable composition comprising a second solvent having mixed therewithin an epoxy and a di-isoimide composition represented by Structure I. In one embodiment, the substrate is a polyimide film. In a further embodiment said second dielectric substrate is a fully aromatic polyimide film or sheet. In a further embodiment the polyimide film has a thickness of 10-50 micrometers. In one embodiment, R 1 is NH 2 . In one embodiment, the coating has a thickness of 10 to 75 micrometers.
In one embodiment, the substrate is coated on both sides thereof. In a further embodiment, the coatings on both sides are chemically identical.
In a further aspect, the present invention is directed to a printed wiring board comprising in order a first layer of a first dielectric substrate, a second layer of one or more discrete electrically conductive pathways disposed upon said first dielectric substrate, a third layer of a bonding layer in adhesive contact with said discrete electrically conducting pathways, and adheringly disposed upon a fourth layer comprising a second dielectric substrate, said bonding layer comprising a curable composition comprising a second solvent having mixed therewithin an epoxy and a di-isoimide composition represented by Structure I.
In one embodiment of the printed wiring board hereof, the first layer is a polyimide film having a thickness of 10-50 micrometers.
In one embodiment of the printed wiring board hereof, the electrically conductive pathways are copper.
In a further embodiment of the printed wiring board hereof, the copper electrically conductive pathways are characterized by a thickness of 10-50 micrometers and lines and spacing from 10-150 micrometers.
In one embodiment of the printed wiring board hereof, in said adhesively bonding layer said second solvent is MEK, cyclohexanone, PMA, DMF, or a mixture thereof.
In one embodiment of the printed wiring board hereof, in said adhesively bonding layer in said di-isoimide composition represented by Structure I, R 1 is NH 2 .
In one embodiment of the printed wiring board hereof, the second dielectric substrate is a polyimide film or sheet. In a further embodiment said second dielectric substrate is a fully aromatic polyimide film or sheet. In a still further embodiment, said second dielectric substrate is a film or sheet comprising a polyimide that is the condensation product of PMDA and 4,4′-ODA. In a still further embodiment, said second dielectric substrate is a fully aromatic polyimide film having a thickness of 10-50 micrometers.
The printed wiring board hereof is conveniently formed by contacting the coating side of the laminated article hereof to the conductive pathways disposed upon the first dielectric substrate. The printed wiring board hereof has several embodiments that differ from one another in the degree of consolidation. In one embodiment the printed wiring board hereof is formed simply by disposing upon a horizontal surface a first dielectric substrate having one or more discrete conductive pathways disposed upon at least one surface thereof, where said conductive pathways are facing upward; followed by placing a coated side of the laminated article hereof in contact with the conductive pathways, thereby preparing a so-called “green” or uncured printed wiring board.
In a further embodiment, the green printed wiring board is subject to pressure thereby causing some consolidation. In a further embodiment the green printed wiring board is subject to both pressure and temperature. The temperature exposure may be sufficient to induce only a small amount of cross-linking or curing. This represents a so-called “B-stage” curing—an intermediate level of consolidation that causes the printed wiring board to have some structural integrity while retaining formability and processibility. The B-stage can be followed by complete curing. Alternatively, complete curing can be effected in a single heating and pressurization step from the green state.
In one embodiment of the printed wiring board hereof, the first dielectric substrate bears conductive pathways on both sides, permitting the formation of the multi-layer construction described supra on both sides of the first dielectric substrate.
In another embodiment of the printed wiring board hereof, the second dielectric substrate is coated on both sides with a composition comprising a solution/dispersion of epoxy, a second solvent, and the di-isoimide composition represented by Structure I.
In still a further embodiment, the first dielectric substrate bears conductive pathways on both sides, and the second dielectric substrate bears a coating on both sides, that coating comprising a solution/dispersion of epoxy, a second solvent, and the di-isoimide composition represented by Structure I. This embodiment permits printed wiring boards hereof to be constructed with an indefinite number of repetitions of the basic structure of the multilayer article.
In a further embodiment, at least a portion of the conductive pathways disposed upon one side of the first dielectric substrate are in electrically conductive contact with at least a portion of the conductive pathways disposed upon the other side of the first dielectric substrate through so-called “vias” that serve to connect the two sides of the dielectric substrate.
In another aspect, the present invention provides a third process, a process for preparing an encapsulated printed wiring board, the process comprising adhesively contacting the coated surface of a laminated article having a surface with a coating disposed thereupon to at least a portion of the discrete conductive pathways disposed upon a dielectric substrate thereby forming a multilayer article; wherein said coating comprises a curable composition comprising a second solvent having mixed therewithin an epoxy and a di-isoimide composition represented by Structure I; and, applying pressure to the printed wiring board so formed at a temperature in the range of 100 to 250° C. for a period of time in the range of 30 seconds to 5 hours, thereby forming an encapsulated printed wiring board.
In one embodiment, the third process hereof further comprises extracting said second solvent before applying pressure to the printed wiring board. Solvent extraction can be effected conveniently by heating in an air circulating oven set at 110° C. for a period of time ranging from 2-20 minutes.
In one embodiment of the third process hereof, R 1 is NH 2 .
In one embodiment of the third process hereof, the first and second dielectric substrates are both polyimide films.
In a further embodiment of the third process hereof, the polyimide films are fully aromatic polyimides.
In a still further embodiment of the third process hereof, the polyimide films are the condensation product of PMDA and ODA.
The invention is further described in the following specific embodiments though not limited thereby.
EXAMPLES
Determining Reaction Completion Point
In the following examples, infrared spectroscopy (IR) was employed to determine the end-point of the reaction. Small aliquots of the reacting medium were withdrawn by dropper-full, dried in a vacuum oven with N 2 purge at about 60° C. for about 60 minutes. Following conventional methodology for preparing solids for IR spectroscopic analysis, the resulting powder was then compounded with KBr followed by the application of pressure to the resulting compound, thereby forming a test pellet. IR absorption peaks at 1836 cm −1 and 1769 cm −1 were monitored to follow the increase in the concentration of the di-isoimide product. Similarly, IR absorption peaks at 1856 cm −1 and 1805 cm −1 characteristic of PMDA and 1788 cm −1 characteristic of melamine were monitored to follow the consumption of reactants. When the PMDA and melamine peaks became undetectable, the reaction was considered to be complete.
Peaks at 1788 cm −1 and 1732 cm −1 characteristic of imide were also monitored to follow the synthesis of any imide by-product of the present process.
The time to reaction completion was observed to vary considerably with the reaction temperature and the particular choice of solvent.
Reaction Medium
Both melamine and PMDA are only slightly soluble in the solvents employed herein so it was necessary to maintain good mixing during reaction to ensure a high degree of conversion. Without constant vigorous mixing, the solids settled and the reaction slowed down or stopped. The amount of energy that was needed for mixing was determined by observation. When the dispersion was of uniform appearance and no stagnant solid phase was observed, mixing was deemed to be of sufficient energy. The di-isoimide product formed into platelet particles with dimensions in the hundreds of nanometers range. These platelet particles also remained suspended with mixing. By the time reaction was completed, no detectable amounts of PMDA or melamine were present in the reaction mixture—all the suspended particles were di-isoimide, or, in some instances, di-isoimide with some imide mixed in.
Printed Wiring Board
A Pyralux® AC182000R copper clad laminate sheet (Dupont Company) was etched according to a common commercial etching process to form a series of parallel copper conductive strips 35 micrometers high, 100 micrometers wide, and spaced 100 micrometers apart. This was used in Examples 9-12, and is referred to therein as “a PWB test sheet.” Information on methods for preparing printed wiring boards can found in Chris A. Mack, Fundamental Principles of Optical Lithography The Science of Microfabrication, John Wiley & Sons, (London: 2007). Hardback ISBN: 0470018933; Paperback ISBN: 0470727306.
Reagents
Except where otherwise noted, all reagents were obtained from Sigma Aldrich Chemical Company.
Example 1
6.31 grams of melamine, 5.45 grams of PMDA and 25 grams of MEK were mixed using a magnetic stirrer in a round bottom flask. The mixture was refluxed under nitrogen for two days until conversion was complete. MEK was added as needed during refluxing to keep the volume of the reaction mixture approximately constant. The thus prepared product mixture was cooled to room temperature while maintaining stirring. As confirmed by IR spectroscopy, the product mixture contained only MEK and di-isoimide. No imide was detectable. The dispersion so prepared was suitable for immediate use in formulating a curable epoxy composition.
Example 2
6.31 grams of melamine, 5.45 grams of PMDA and 35 grams of ethyl 3-ethoxypropionate were mixed in a round bottom flask. The mixture was refluxed under nitrogen for two days until conversion was complete. The mixture was cooled to room temperature. A small sample from the mixture was washed with MEK. As confirmed by IR spectroscopy, the product mixture contained MEK, di-isoimide, and a small amount of imide indicated by a small IR peak at 1734 cm −1 . The dispersion so prepared was suitable for immediate use in formulating a curable epoxy composition.
Example 3
69.69 grams of melamine (0.534 moles), 60.26 grams of PMDA (0.267 moles) and 360 grams cyclohexanone are added into a reaction vessel, and stirred at room temperature for 6 days until conversion was complete. A sample from the reaction mixture was dried in vacuum oven. IR spectra of the final solid product showed the disappearance of the PMDA peaks at 1856 & 1805 cm −1 and melamine peak at 1558 cm −1 and the appearance of the isoimide peaks at 1836 & 1769 cm −1 .
Example 4
6.31 grams of melamine, 5.45 grams of PMDA and 25 grams of MIBK (methyl isobutyl ketone) were mixed in a round bottom flask. The mixture was refluxed under nitrogen for 90 minutes. The mixture was cooled to room temperature. A sample was dried. IR spectra of the dried sample showed the formation of isoimide (peaks at 1836 & 1769 cm −1 ). Reaction was complete to the di-isoimide and no imide was detected.
Example 5
5.81 grams of melamine, 5.00 grams of PMDA, 10 grams of DMF and 10 grams of ethyl acetate were mixed overnight in a flask at room temperature. Reaction was complete to the di-isoimide and no imide was detected. A small sample was dried. IR spectra of the dried sample showed the formation of isoimide (peaks at 1836 & 1769 cm −1 ).
Example 6
5.81 grams of melamine, 5.00 grams of PMDA, 10 grams of MIBK, and 10 grams of toluene were mixed overnight in a flask at room temperature. A small sample was dried. IR spectra of the dried sample showed the formation of isoimide (peaks at 1836 & 1769 cm −1 ). Reaction was complete to the di-isoimide and no imide was detected.
Example 7
3 grams of Vamac® G (from DuPont) and 12 grams of MEK were mixed in a round bottom flask to form a solution. 3.30 grams of a phenol/formaldehyde resin (GP 5300 from Georgia Pacific), and 15 grams of DMF were added to the round bottom flask, and mixed to form a solution. 3.48 grams of melamine and 3.01 grams of PMDA were added to the solution. The solution was heated under nitrogen for 30 minutes at 100° C., 30 minutes at 120° C., and 60 minutes at 140° C. The mixture was cooled to room temperature. A small sample from the mixture was washed thoroughly in MEK (to remove GP5300 and Vamac-G). IR spectra show the formation of isoimide (peaks at 1836 & 1769 cm −1 ) The anhydride and melamine peaks disappeared while the isoimide peaks appeared, and a small amount of imide was also present as indicated by a very small peak at 1734 cm −1 .
Example 8
2.90 grams of carboxyl-terminated butadiene-acrylonitrile rubber (CTBN rubber, 1300×13 from CVC Thermoset Specialties), 3.78 grams of melamine, 3.27 grams of PMDA and 15 grams of dry MEK were mixed in a round bottom flask. The solution was refluxed under nitrogen for 5 hours. The mixture was cooled to room temperature. A small sample from the mixture was washed thoroughly in MEK (remove CTBN). IR spectra of this sample showed the formation of isoimide (peaks at 1836 & 1769 cm −1 ). The anhydride and melamine peaks disappeared. A small amount of imide was present.
Comparative Example A
In a reaction vessel, 25.22 grams of melamine (0.2 moles), 21.81 grams of PMDA (0.1 moles) and 125 ml DMF were refluxed for 5 hours. The mixture was cooled and quenched with methanol. The solid product was filtered and dried. The IR spectra of the filtered solid product showed the disappearance of the PMDA peaks at 1856 & 1805 cm −1 and of the melamine peak at 1558 cm −1 and the appearance of the imide peaks at 1788 & 1732 cm −1 .
Comparative Example B
In a reaction vessel, 50.45 grams of melamine (0.4 moles), 43.62 grams of PMDA (0.2 moles) and 400 ml of NMP (N-methylpyrrolidinone) were refluxed for 30 minutes. The mixture was cooled and quenched with methanol. The solid product was filtered and dried. The IR spectra of the filtered solid product showed imide formation (peaks at 1788 & 1732 cm −1 ).
Example 9
3.50 grams of the di-isoimide dispersed in 9.5 grams of cyclohexanone, prepared in Example 3 supra, and 11.5 grams of a copolymer of butadiene and acrylonitrile modified to contain free carboxylic groups (Nipol 1072J from Zeon Chemicals) dissolved in 63 grams of MEK, were mixed in a flask. 11.20 grams of melamine phosphate/melamine polyphosphate/melamine pyrophosphate flame retardant (Phosmel 200 Fine from Nissan Chemical Industries) was then added and mixed in, to form a first solution/dispersion. 9.10 grams of an epoxy-rubber adduct (HyPox RK84L from CVC Thermoset Specialties) was dissolved in 9.10 grams of MEK to form a second solution. The second solution was added to the first solution/dispersion thereby forming an epoxy solution/dispersion. The epoxy solution/dispersion so prepared was coated onto 12 micrometer thick Kapton® 50FPC polyimide film using a 7 mil gauge (177.8 micrometer) doctor blade followed by removal of the solvent by placing the thus-cast film and substrate in a vacuum oven at 60° C. for one hour, to form an approximately 25 micrometer thick coating.
The thus prepared coated Kapton® was then used as a cover-layer on the PWB test sheet. Referring to FIG. 1 , the Kapton® 50FPC film, 1 , coated with the curable composition, 2 , thus prepared was contacted, 5 , to the copper conductive strips, 3 , of the PWB test sheet, 4 , the curable composition, 2 , being in direct contact with the copper conductive strips, 3 . The printed wiring board thereby formed, 6 , was then consolidated, 7 , under vacuum in an OEM Laboratory Vacuum Press by holding the printed wiring board at 175° C. and 2.25 MPa for 80 minutes, thereby forming a flexible printed wiring board, 8 , having fully encapsulated copper conductive pathways.
Example 10
3.50 grams of the di-isoimide dispersed in 9.5 grams of cyclohexanone, as prepared in Example 3, and 9.80 grams of “Nipol 1072J” rubber dissolved in 55 grams of MEK were mixed in a flask. The mixture was stirred for 30 minutes. 1.40 grams of CTBN (Carboxyl-Terminated Butadiene-Acrylonitrile Rubber, CTBN 1300×13 from CVC Thermoset Specialties) and 11.20 grams of “Phosmel 200 Fine” flame retardant (from Nissan Chemical Industries) were added to the mixture. 9.10 grams of HyPox RK84L were dissolved in 13.7 grams of MEK and the solution so formed was added to the mixture. The thus prepared solution/dispersion was coated onto a 12 micrometer thick Kapton® 50ENS polyimide film using a 7 mil gauge (177.8 micrometers) doctor blade, after which the thus coated Kapton® film was placed into an air circulating oven at 110° C. for 10 minutes to remove the solvent. The dry adhesive film thickness was 27 micrometers.
The thus prepared coated Kapton® film was used to prepare a fully encapsulated flexible printed wiring board employing the materials and procedures described in Example 9.
Example 11
61.60 grams of “Nipol 1072J” rubber were dissolved in 350 grams of MEK in a flask to form a first solution. 9.10 grams of the di-isoimide dispersed in 25 grams of cyclohexanone prepared in Example 3 was mixed into the first solution to form a second solution/dispersion, followed by mixing in 42.25 grams of “Phosmel 200 Fine” flame retardant (from Nissan Chemical Industries) to form a third solution/dispersion. 34.45 grams of HyPox RK84L was dissolved in 34.45 grams of MEK and the resulting fourth solution was mixed into the third solution/dispersion to form a fifth solution/dispersion. 2.6 grams of bisphenol A diglycidyl ether epoxy resin (EPON™ 828 from Hexion Specialty Chemicals) were mixed into the fifth solution/dispersion to form an epoxy solution/dispersion. The thus prepared epoxy solution/dispersion was coated onto a Kapton® 50FPC polyimide film using a 7 mil gauge (177.8 micrometer) doctor blade. The thus coated Kapton® film was placed in an air circulating oven at 110° C. for 10 minutes to remove the solvent. The dry coating thickness was approximately 25 micrometers in thickness.
The thus prepared coated Kapton® film was used to prepare a fully encapsulated flexible printed wiring board employing the materials and procedures described in Example 9.
Example 12
55.8 grams of a cyclohexanone dispersion of melamine-PMDA di-isoimide (26.9 weight % isoimide content) prepared according to the method of Example 3 and 51.0 grams of rubber (copolymer of butadiene and acrylonitrile modified to contain free carboxylic groups—Nipol 1072J from Zeon Chemicals) were dissolved in 289 grams of MEK to form a solution. 36 grams of an epoxy-rubber adduct (HyPox RK84L from CVC Thermoset Specialties) and 48.0 grams of melamine phosphate/melamine polyphosphate/melamine pyrophosphate flame retardant (Phosmel 200 Fine from Nissan Chemical Industries) were mixed into the solution using a mechanical stirrer. When all the ingredients were dispersed into the solution, the mixture so formed was homogenized for 2.5 minutes (Silverson model L5M homogenizer) to a dispersion having a visually uniform appearance. The thus homogenized mixture was then mechanically stirred continuously until coating, described infra, was commenced.
The dispersion so prepared was coated onto Kapton® 50FPC polyimide film using a 7 mil gauge (177.8 micrometer) doctor blade. The solvent was removed by placing the thus coated Kapton® film in an air circulating oven for 10 minutes at 110° C. The dried coating thickness was approximately 25 micrometers.
The thus dried coated film was laminated to a PWB test sheet. The printed wiring board, 6 , as shown in FIG. 1 was further prepared with a release film and a rubber pad on each side. The combination thus prepared was inserted into a quick lamination press and pressed at a temperature of 185° C. and a pressure of 9.8 MPa for 2 minutes, followed by a cure in an air-circulating oven at 160° C. for 90 minutes.
The adhesion of the coated film to the PWB test sheet was determined to be 2.16 N/mm (Newton/millimeter) according to ISO 6133 IPC-TM-650 2.4.9 using a German wheel attached to an Instron machine.
Example 13
The materials and procedures of Example 12 were employed, except that the quantities were different, as indicated in Table 1, and the procedure was modified as described infra.
Ex. 12 (g) Ex. 13 (g) Melamine-PMDA isoimide (26.9 55.8 33.85 weight-% isoimide) dispersion in Cyclohexanone Nipol 1072J 51.0 41.6 MEK 289 235.7 HyPox RK84L 36 34.5 Phosmel 200 Fine 48.0 42.25
The melamine-PMDA isoimide cyclohexanone dispersion, Nipol 1072J, and MEK were combined to form a first solution, to which the Phosmel 200 Fine was added to form a first solution/dispersion. The HyPox RK84L was first dissolved in 34.5 grams of MEK to which 2.6 grams of Epon 828 (from Hexion) were added, thus forming a second solution. The second solution was then added to the first solution/dispersion. The remaining procedures and method of Example 12 were then followed. The adhesion of the coated film on the PWB test sheet was determined to be 2.15 N/mm. | The present invention deals with a flexible printed wiring board in the form of a printed wiring board wherein the conductive elements are fully encapsulated by an epoxy adhesive comprising a novel aromatic di-isoimide chemical compound. The conductive elements are thereby protected. The flexible printed wiring board is readily cured at a temperature in the range of 100 to 250° C. However, before curing, by virtue of the latent cure feature of the epoxy adhesive, the adhesive component of the printed wiring board has an extended shelf life, and avoids premature curing during processing. | 8 |
FIELD OF THE INVENTION
This invention relates to electrostatic recorders including a recording medium which is transported past a charging region located between recording electrodes and counter electrodes in the form of backplates. More particularly, this invention relates to a low cost, easily constructed, improved continuous counter electrode structure having an advantageous contact pressure distribution.
BACKGROUND OF THE INVENTION
Electrostatic printing upon an image recording medium comprises the formation of a latent, electrostatic image by the selective creation of air ions and the deposition of those ions of a given sign (usually negative) at selected pixel locations on the recording medium. The aggregate of the charged pixel areas forms an electrostatic latent (i.e. non-visible) image which is subsequently made visible at a development station. Development may be accomplished by passing of the recording medium, bearing the latent image, into contact with a liquid solution containing positively charged dye particles in colloidal suspension. The dye particles will be attracted to the negatively charged imaging ions so as to render the image visible. The visual density of the image thus developed will be a function of the potential or charge density of the electrostatic image.
Two types of image recording media in common usage are paper and film. The paper is specially treated so that its bulk will be electrically conductive and is overcoated with a thin dielectric coating on its image bearing side. The film comprises a dielectric substrate (such as Mylar®) overcoated with a very thin, semi-transparent intermediate conductive layer and a surface dielectric layer upon its image bearing side. To write on the media, electrical contact must be made to bleed off electrical charge. For film, electrical contact is made by conductive stripes painted near the edges of the media which penetrate the dielectric layer to make electrical contact with the conductive inner layer of the media. When writing on paper media, electrical contact is made directly to the backside of the paper. The backplate portion of the writing potential is established in the paper conductive layer by direct contact thereof with the conductive counter electrodes, that is, by essentially resistive coupling. When writing on film, the backplate portion of the writing potential is established in the intermediate conductive layer by capacitive coupling, through the Mylar substrate, between the intermediate conductive layer and the counter electrodes.
Conventionally, an electrostatic image may be formed upon the thin surface dielectric layer of a paper recording medium by passing the recording medium between a recording head, including an array of recording stylus electrodes, and a counter electrode comprising an array of complementary counter electrode segments. A charge is applied to selected pixel locations on the recording medium by the coincidence of voltage pulses applied to opposite surfaces thereof, by the stylus electrodes and the counter electrodes. When the potential difference between the stylus electrodes and the conductive layer of the recording medium is large enough to cause the voltage in the air gap between the stylus electrodes and the surface of the dielectric layer to exceed the breakdown threshold of the air, the air gap becomes ionized and air ions, of the opposite sign to the potential of the conductive layer, are attracted to the surface of the dielectric layer. As the dielectric surface charges up, the voltage across the gap will decrease to a value below the maintenance voltage of the discharge. At that time, the discharge extinguishes, leaving the dielectric surface charged. A potential difference of about 600 volts (about 800 volts for film) is required to establish a discharge. Of that threshold potential, about -200 volts is imposed on the stylus electrodes contemporaneous with the application of about +400 volts (+600 volts for film) on the counter electrodes.
Electrostatic recorders may be typically from 11 inches to 44 inches wide, and in some cases even as wide as 72 inches. Therefore, the writing head stylus array which extends fully across this width may have as many as 2000 to over 17,000 styli (at resolutions of 200 to 400 dots per inch). Because of this very large number of styli it is ordinarily not economically attractive to use a single driver per stylus, and a multiplexing arrangement is commonly used in conjunction with the above-described electrostatic discharge method. The styli in the writing head array are divided into stylus electrode groups (each group being about 0.64 inch to 2.56 inches long) so that each may consist of several hundred styli. The stylus electrodes are wired in parallel with like numbered styli in each group being connected to a single driver and carrying the same information. Writing will only occur in the stylus group whose complementary counter electrode is pulsed.
In U.S. Pat. No. 4,424,522 (Lloyd et al) entitled "Capacitive Electrostatic Stylus Writing With Counter Electrodes" there is disclosed a backplate electrode assembly which is conformable to the arcuate crown of the recording head. A structure of this type is illustrated in FIGS. 1 and 2, and is more fully described below. It comprises a plurality of segments of an electrically resistive material mounted upon an elongated, U-shaped, support bar so as to be electrically independent. The segments are anchored to the support bar and are stretched over the channel thereof within which is provided a resilient member for urging the surface of the resistive material into intimate contact with the recording medium. In its commercial application, in electrostatic printer/plotters manufactured by the assignee of the present patent application, the resilient member comprises a strip of foam and an oil-filled bladder for urging the segmented backplate electrodes toward the writing head.
The complexity of the biasing elements of the backplate electrode structure described above increases the cost of manufacture. Furthermore, uniform wrapping tension of each segment upon the support bar is difficult to achieve, and insufficient tension can result in curling of the segment edges which allows debris and chaff to collect in the gaps and thus provide a shorting path. Non-uniform tension along the writing line can also cause image intensity variations across the plot and wear variations across the writing head which result in image striations, i.e. visible striping on the printed image extending in the direction of movement of the recording medium. As the pressure applied by the biasing elements against the recording head increases, so does the likelihood of flaring because flare writing increases with pressure as the media's surface abrades the ends of the styli. Flaring is a phenomenon caused by non-uniform electrical discharge which results in non-uniform electrostatic image spots being created on the recording medium.
Therefore, the objects of the present invention are to overcome these shortcomings by providing a counter electrode in which the biasing element, for urging the electrically conductive material against the recording head, is of simple and inexpensive construction and will conform to the shape of the recording head. Furthermore, it would be desirable if the counter electrode could provide a non-uniform contact pressure sufficient to conform the media to the recording head surface with a minimum force being applied along the nib line.
SUMMARY OF THE INVENTION
These and other objects may be obtained, in one form, by providing an improved counter electrode assembly for an electrostatic recorder. The recorder applies electrical charges, in image configuration, upon a movable image recording member by means of a stylus electrode array and a counter electrode assembly aligned with one another and between which the image recording member may be moved. Both the stylus electrode array and the counter electrode assembly are positioned so as to extend transversely to the direction of movement of the image recording member. The counter electrode assembly comprises a support member, an elastica sheet member anchored to the support member and bowed toward the stylus electrode array, and an electrically resistive member urged by the elastica sheet toward the stylus electrode array.
BRIEF DESCRIPTION OF THE DRAWINGS
Other objects and further features and advantages of this invention will be apparent from the following, more particular, description considered together with the accompanying drawings, wherein:
FIG. 1 is a perspective view of a known charging station for an electrostatic recorder having writing styli and counter electrodes disposed on opposite sides of an image recording medium,
FIG. 2 is an enlarged sectional view of the counter electrode shown in FIG. 1,
FIGS. 3 and 4 are sectional views of two embodiments of the counter electrode structure in accordance with the present invention, wherein the resistive electrode member is secured to an elastica sheet, and
FIGS. 5 and 6 are sectional view of two further embodiments of the counter electrode structure in accordance with the present invention, wherein an elastica sheet urges the conventional resistive electrode member outwardly.
DETAILED DESCRIPTION OF THE INVENTION
Turning now to the drawings, there is illustrated in FIGS. 1 and 2 the relevant image forming elements of a known electrostatic stylus recorder 10. It includes a writing head 12 and a cooperating, conformable counter electrode 14 for depositing a latent electrostatic image on the dielectric surface coating of a web-like image recording medium 16. The recording medium is provided on a supply spool 18 and is advanced in the direction of the arrow A to pass between the writing head 12 and the counter electrodes 14. An appropriate tension force is applied to ensure that the web 16 is advanced at a controlled rate. Guide rollers 22 and 24 cause the web 16 to wrap over the crown of the writing head 12 at a suitable wrap angle. The writing head 12 comprises a linear array of conductive styli, or nibs, 26 embedded within insulating support member 28 along a central elongated nib line (indicated by a central phantom line 30 in subsequent Figures). Nib drivers pulse the styli at appropriate voltages in a timed manner, in accordance with the information to be printed. It should be understood that there may be more than one such linear styli arrays displaced from one another in the direction of web movement, with each of the styli of one array being laterally offset from each of the styli of the other arrays, usually by one half the inter-styli spacing, in order to obtain full density printing.
The known counter electrodes 14 most commonly comprise an insulating U-shaped support bar 32 upon which are mounted resistive electrode segments 34. The segments are cut from a composite sheet formed from a Dacron gauze, or other like material, with a carbon loaded polymer mixture pressed into both of its surfaces. The sheet is about 5-10 mils thick and has the desired characteristics of strength and lubricity, and has a resistivity in the range 90-150 kΩ/square. Great care must be taken during mounting to accurately space the segments 34 from one another by a minimal distance (to reduce striations) and yet to prevent electrical contact therebetween. Counter electrode drivers 36 are in electrical contact with the electrode segments 32 by contact pads 38 formed on a printed circuit board (not shown) which overlie the ends 40 of each electrode segment 34. The electrode segment is a flaccid, clothlike material. A central portion of each electrode segment overlies the open mouth of the support bar 32 and is maintained in conforming contact with the writing head 12 by an outward (relative to the support bar) force applied to its back side by the resilient foam member 42 and the fluid filled bladder 44.
A non-segmented resistive counter electrode, extending the entire length of the writing head is described in a copending patent application assigned to the same assignee as the instant application. It bears U.S. Ser. No. 07/706,708, is entitled "Counter Electrode for an Electrostatic Recorder" (Hansen et al) and is hereby fully incorporated by reference. It comprises a substrate upon which are supported a plurality of electrically conductive traces each extending substantially in the process direction. The traces are interconnected by a layer of resistive material. Electrical potentials are applied to spaced regions of the counter electrode trace array via contact pads connected to periodically spaced traces.
The purpose of the counter electrode structure is two-fold, first it provides the electrical bias to be coupled to the conductive bulk of the paper media or the conductive layer of the film media and, second it provides the outward force to conform the media to the recording head. We have invented a unique counter electrode structure which will accomplish these purposes in a more simple and less expensive manner than has heretofore been available. Our structure relies on sheets of elastica. By the term elastica we mean elastic material which undergoes large deflections. Elasticity is the property of a body, when deflected, to automatically recover its normal configuration as the deflecting forces are removed. For elastic elements undergoing small deflections, the deflection is proportional to the deflecting force. This linear response does not exist for the elastica.
One form of the improved counter electrode structure of the present invention is shown in FIG. 3 wherein the ends of an elastica sheet 50 are anchored in recesses 52 in the support bar 54 and segments 56 of the resistive electrode are laminated, or otherwise secured thereto. Elastica sheet 50 may be about 2 to 5 mils thick and made of Mylar®, Kapton® or some similar material which will have comparably elastic and insulative properties. Alternatively, spaced regions of a resistive polymer ink or paint may be applied directly to the substrate. Electrical contact may be made with the resistive electrodes by contact pads 58. By securing the resistive segments directly to the elastica sheet 50, they may be very closely spaced yet be prevented from touching or shorting. This simplifies close-tolerance manufacture. The free surface of the elastica sheet bows away from the support bar 54 and, when urged against the writing head 12, will provide the necessary force required to deform into conformity with the surface of the writing head and to hold the recording medium firmly thereagainst.
Increasing the force of the writing head against the elastica sheet, beyond a threshold amount, will increase its deflection and will cause its center to buckle away from the head (as shown in dotted lines). This would be an unsatisfactory mode of usage because the recording medium would be unsupported over the nib line. However, we believe that an optimum mode of usage would result from a sub-threshold writing head force of a magnitude sufficient to off-load the nib line, but insufficient to buckle away from it. In this manner, the recording medium will be held in contact with the recording head but there will be very little pressure over the nib line and less abrasion of the styli ends.
An alternative to the segmented resistive material is illustrated in FIG. 4. It shows in a narrow stripe 60 of a continuous length of resistive material having conductive traces 62 embedded therein, (as disclosed in copending application U.S. Ser. No. 07/706,708) laminated over the center of the elastica sheet 50. This continuous structure may also be formed directly upon the elastica sheet by first depositing the traces (e.g. sputtering copper or painting with a conductive ink) thereupon and then overcoating with a resistive material.
In the embodiment of our invention illustrated in FIGS. 5 and 6, the resistive material 64 may be the conventional flaccid material described with regard to FIG. 2. Therefore, it is necessary to provide a force applying member for urging the resistive material against the recording medium. As illustrated, a novel force applying member is positioned within the channel 66 of the U-shaped support bar 68. Our significantly cost reduced and easily manufactured counter electrode utilizes, in FIG. 5, a single elastica sheet 70 anchored in slots 72 in the support bar. In FIG. 6 there is shown a configuration with a pair of elastica sheets 74 and 76 anchored in slots 72 and 78. In each case, the spring action of the bowed elastica sheet urges the resistive material toward the writing head.
However, in the FIG. 6 embodiment, there will be a reliable off-loading of the nib line. Alternatively, the force applying member may be located at the exterior of the support bar 68, in a manner similar to that illustrated in the FIGS. 3 and 4 embodiments.
It should be understood that numerous changes in details of construction and the combination and arrangement of elements and materials may be resorted to without departing from the true spirit and scope of the invention as hereinafter claimed. | An improved counter electrode assembly for an electrostatic recorder in which the recorder applies electrical charges, in image configuration, upon a movable image recording member by means of a stylus electrode array and a counter electrode assembly aligned with one another and between which the image recording member may be moved. Both the stylus electrode array and the counter electrode assembly are positioned so as to extend transversely to the direction of movement of the image recording member. The counter electrode assembly comprises a support member, an elastica sheet member anchored to the support member and bowed toward the stylus electrode array, and an electrically resistive member urged by the elastica sheet toward the stylus electrode array. | 1 |
BACKGROUND OF THE INVENTION
The invention relates to an electroluminescent device having an electroluminescent element, which includes an electroluminescent organic layer, which contacts two electrodes, the electroluminescent element being enclosed in a housing.
An electroluminescent (EL) device is a device which, while making use of the phenomenon of electroluminescence, emits light when the device is suitably connected to a power supply. If the light emission originates in an organic material, the device is referred to as an organic electroluminescent device. An organic EL device can be used, inter alia, as a thin light source having a large luminous surface area, such as a backlight for a liquid crystal display or a watch. An organic EL device can also be used as a display if the EL device comprises a number of EL elements, which may or may not be independently addressable.
The use of organic layers as an EL layer in an EL element is known. Known organic layers generally include a conjugated, luminescent compound. This compound may be a low-molecular dye, such as a coumarin, or a high-molecular compound, such as a poly(phenylenevinylene). The EL element also includes two electrodes, which are in contact with the organic layer. By applying a suitable voltage, the negative electrode, i.e. the cathode, will inject electrons and the positive electrode, i.e. the anode, will inject holes. If the EL element is in the form of a stack of layers, at least one of the electrodes should be transparent to the light to be emitted. A known transparent electrode material for the anode is, for example, indium tin oxide (ITO). Known cathode materials are, inter alia, Al, Yb, Mg:Ag, Li:Al or Ca. Known anode materials are, in addition to ITO, for example, gold and platinum. If necessary, the EL element may comprise additional organic layers, for example, of an oxydiazole or a tertiary amine, which serve to improve the charge transport or the charge injection.
An EL device of the type mentioned in the opening paragraph is disclosed in a publication by Burrows et. al., published in Appl. Phys. Lett. 65 (23), 1994, 2922. The known device consists of an organic electroluminescent element which is built up of a stack of an ITO layer, an EL layer of 8-hydroxyquinoline aluminium (Alq 3 ), a hole-transporting layer of N,N-diphenyl-N,N-bis(3-methylphenyl)1,1-biphenyl-4,4'diamine and an Mg:Ag layer, which is provided with a silver layer. Said EL element is surrounded by a housing consisting of a bottom plate and a top plate which are made of glass, said plates being interconnected by an epoxy-based adhesive for sealing. The ITO layer also forms the electrical leadthrough for the anode; the Mg:Ag/Ag layers also form the electrical leadthrough for the cathode. The leadthroughs are electrically insulated from each other by a layer of silicon nitride. The known device has disadvantages which render it unsuitable for use in durable consumer goods, such as a display or a backlight for a liquid crystal display or a watch. After several hours, a deterioration of the uniformity of the luminous surface occurs which can be observed with the unaided eye. The deterioration, which also takes place when the EL device is not in operation, manifests itself, for example, by so-called "dark spots" which are formed so as to be dispersed over the entire luminous surface. Also the presence of the housing itself gives rise to degradation of the EL device. For example, the epoxy-based adhesive gives off substances which are detrimental to the EL element. In addition, the manufacture of the EL device is time consuming. For example, the curing of a suitable epoxy-based adhesive takes 24 hours.
SUMMARY OF THE INVENTION
One of the objects of the invention is to overcome, or reduce, these disadvantages. The invention specifically aims at an EL device of which the uniformity of the luminous surface exhibits a deterioration in the course of time which can hardly, if at all, be observed with the unaided eye when the device is stored or operated under atmospheric conditions which may or may not be extreme. The invention particularly aims at precluding "dark spots" caused by the action of air and water. A further object is to provide an EL device which is compact and robust under normal production and operating conditions, and which exhibits a satisfactory resistance to mechanical and varying thermal loads. In addition, it should be possible to manufacture said EL device in a simple and cheap manner without the necessity of using, for example, expensive vacuum equipment for its manufacture. The housing should be such that neither its presence nor its manufacture give rise to degradation of the EL element. The performance of the EL element, for example measured in terms of luminance at a given voltage, should be comparable to corresponding elements which are stored or operated in an inert atmosphere.
These objects are achieved by an EL device of the type mentioned in the opening paragraph, which is characterized in accordance with the invention in that the housing includes a low-melting metal or a low-melting metal alloy, while forming an airtight and waterproof housing.
The use of a housing which is sealed by a low-melting metal or a low-melting metal alloy, which is provided from the melt or at a temperature near the melting point, enables an EL device to be obtained having a luminous surface whose uniformity exhibits no visible deterioration when the device is stored for at least 650 hours or operated for at least 400 hours under atmospheric conditions. In particular "dark spots" visible with the unaided eye are not observed, not even under extreme conditions. For example, exposure to alternating hot and cold baths of hot water and icewater for several days does not adversely affect the uniformity of the luminous surface of the EL device, which also proves that the EL device has good resistance to mechanical and varying thermal loads. The thickness of the EL device typically is several millimeters and of the same order of magnitude as EL devices which are not provided with the housing in accordance with the invention. Said housing can be manufactured in a few minutes, and sealing of said housing takes only approximately ten seconds. The manufacture of the housing does not require expensive vacuum equipment. It has been found that the performance of the device is comparable to that of EL elements which are operated and stored in nitrogen. In a typical example, in which a poly(phenylenevinylene) was used as the EL material, the luminance was 200 Cd/m 2 at 5.5 V and the EL efficiency was 1.2%.
Extensive experiments carried out by the inventors showed that the degree to which the housing should be airtight and waterproof must be such that organic materials cannot be employed as barrier materials in the housing. Even epoxy-based adhesives and high-molecular, halogenated or non-halogenated hydrocarbons, which are reputed to be the best barrier materials within the class of organic materials, are unsuitable. For example, apart from the worse barrier properties, the large difference between the coefficients of expansion of these materials and, for example, glass, and the resulting bonding problems proved to be disadvantageous. In addition, a conclusion which can be drawn from this is that the organic EL layer of the EL element must be screened completely by the housing.
The choice of the metal used to seal the housing is limited, in accordance with the invention, by the melting point. It is essential that the metal or metal alloy used for sealing has a low melting point to preclude damage to the EL element when the metal or metal alloy is processed from the melt. In this connection, a metal or metal alloy is considered to have a low melting point if processing from the melt does not lead to thermal degradation of the organic EL layer. The permissible melting point can be higher as the spacing between the metal and the organic EL layer of the element is greater, or as the time during which the element is exposed to the elevated temperature is shorter. If the intended application of the EL device does not require a compact housing, use can even be made of a low-melting glass having a melting point, for example, of 400° C. However, the melting point must not be so low that the metal melts under normal operating conditions of the EL device.
From the above, it can be concluded that a suitable metal or metal alloy preferably has a melting point in the range between 80° C. and 250° C. The metal is more widely applicable if the melting point ranges between 90° C. and 175° C., or better still, between 100° C. and 150° C., the optimum melting point being approximately 110° C.
A particular, preferred embodiment is characterized in accordance with the invention in that the metal alloy includes an element selected from the group formed by In, Sn, Bi, Pb, Hg, Ga and Cd. Many types of low-melting metal alloys are commercially available at a low price. The majority of the commercially available alloys include an element of the above group. Apart from a broad spectrum of melting points, these metals also offer a broad spectrum of other properties which are important for the housing, such as sensitivity to oxidation, adhesion to materials to be combined, such as glasses and indium tin oxides, coefficient of thermal expansion, ductility, dimensional stability, degree of shrinkage upon solidification and wetting. In applications in which toxicity is an important factor, alloys containing Hg or Cd, such as Sn (50 wt. %) Pb (32 wt. %) Cd (18 wt. %) are not to be preferred. If a somewhat flexible EL device is necessary, it is advantageous to use a ductile low-melting metal, such as indium (melting point 157° C.) or Sn(35.7 wt. %)-Bi(35.7 wt. %)-Pb(28.6 wt. %), which has a melting point of 100° C. To minimize stresses caused by solidification, a metal which, upon solidification, does not form crystalline domains and exhibits little shrinkage, such as Bi(58 wt. %)-Sn(42 wt. %), melting point 138° C., is to be preferred.
Sealing of the housing by means of a low-melting metal or a low-melting alloy proves to be surprisingly simple. Methods which are known per se and which are suitable for mass manufacture and for large surfaces, prove to be suitable. Suitable methods are, inter alia, thermocompression, soldering, spray coating, or if local heating is desirable, melting by means of, for example, a laser. Particularly suitable methods are foil melting, dip coating or drop casting. These methods have in common that the metal is processed from the melt. As a result, these techniques do not require expensive vacuum equipment and, in addition, enable relatively thick layers, typically, of hundred micrometers to be formed in a short period of time, typically, approximately ten seconds. To obtain an airtight and waterproof seal, it is important that the metal can be provided from the melt in a sufficiently large thickness. A suitable layer has a thickness in excess of one micrometer, for example approximately ten micrometers, or better still, several hundred micrometers. As regards other properties, such as flexibility, it is advantageous to use a smaller layer thickness of 1 to 10 micrometers.
A particular embodiment in accordance with the invention is characterized in that the low-melting metal or the low-melting alloy is provided with a bonding layer. The resistance to mechanical and varying thermal loads can be improved further if the device is provided with a bonding layer before the metal is applied. A further advantage of the use of a bonding layer is that the metal can be provided in accordance with a pattern while using differences in wettability. In this manner, a patterned, low-melting metal layer can be formed by means of dip coating. In addition, the bonding layer serves as a barrier to any diffusion of atoms from the low-melting metal towards the EL element.
The bonding layer can be provided, for example, by electroless deposition of silver and/or a nickel phosphor. A particularly suitable bonding layer is obtained by screen printing of a solderable, silver-containing glass paste. In this manner, the bonding layer, having a thickness of typically several tens of micrometers, can be provided in accordance with a pattern and in a short period of time without the use of vacuum equipment. If necessary, suitable bonding layers, containing, for example, Ag, Ni, Cr, Cu or Pt, can alternatively be provided by vapor deposition or sputtering, whether or not by simultaneously or successively using different sources. A stack of bonding layers can also be obtained in said manner. Particularly Cr/Ni, Cr/Ni/Ag, Pt/Ag and Pt/Cu stacks can suitably be used as a bonding layer between the EL element and the low-melting metal. Vapor-deposited or sputtered layers on the basis of Ni, Ni/Cu, Ni/Ag, Cr/Ni, Cr/Ni/Ag and Pt/Ag can suitably be used as the bonding layer between glass and the low-melting metal. V or Ti can be used instead of Cr. Bonding layers thus provided typically have a layer thickness of 100 to 500 nm.
A further preferred embodiment of the invention is characterized in that the housing comprises an electrical leadthrough which is at least partly enclosed in a low-melting glass. To apply a voltage across the electrodes of the EL element, the housing must be provided with at least two electrical leadthroughs. To preclude a short-circuit, the leadthroughs must be electrically insulated from other parts of the housing and, in particular, from each other. For this purpose, use can be made of airtight and waterproof insulators such as silicon nitride and silicon oxide, which are known per se.
Preferably, however, a low-melting glass is used as the insulator. The expression "low-melting glass" is to be understood to mean herein a glass having a melting point which is so low that, if said glass is processed from the melt, it does not adversely affect the operation of the EL device. This means that, given the thermal resistance of the organic EL layer, the low-melting glass can only be provided when the organic EL layer does not yet form part of the EL device in process of formation. It has been found that low-melting glasses provided on an ITO layer do not adversely affect the properties of the ITO layer.
Many variants of low-melting glasses having minimum melting points of approximately 350° C. are commercially available. Suitable glasses are, for example, lead-borate glasses filled with ceramic materials. The low-melting glass layer can be provided, whether or not in accordance with a pattern, by means of methods which are known per se, such as screen printing. In these methods, glass powder is formulated so as to form a paste which is provided on the substrate, whereafter said paste is sintered in a furnace, thereby forming the electrically insulated, airtight and waterproof glass.
Various variants of the housing are possible. In a first variant, the EL element is surrounded by two shaped parts, for example two glass plates, which are interconnected by means of a closed ring of a low-melting metal or metal alloy. The specific shape of the parts determines how many of such rings are necessary to seal the housing. For example, to seal a disc-shaped dial plate of a watch, which is provided with a duct for interconnecting the dials and the drive mechanism, two such rings are necessary.
A second variant uses one shaped part on which the EL element is positioned and which serves as the substrate. The housing is sealed by providing the entire EL element, as well as the regions of the shaped part adjoining the EL element, with a coating of a low-melting metal or alloy. Unlike the first variant, the presence of a cavity between the metal and the EL element will be avoided by providing the metal in liquid form. As, in the last-mentioned variant, the molten metal directly contacts the EL element, it is essential to use a low-melting metal.
The shaped parts can be manufactured from airtight and waterproof materials which are known per se. Suitable materials are, for example, high-melting metals, metal alloys or glass. As regards the light emission, it is advantageous to manufacture one of the shaped parts from a material which is transparent to the light to be emitted. Moreover, to save space, it is advantageous to use this shaped part as the substrate for the EL element.
Electrical leadthroughs can be realized in many ways. For example, an electrically conducting, transparent shaped part, such as a glass plate provided with a layer of ITO, can be used as an electrical leadthrough, while an electrically insulating, transparent shaped part is suitable to realize patterned or independently addressable lead-throughs and electrodes. A housing which is simple in terms of construction can be obtained by using the low-melting metal or metal alloy as the electrical leadthrough. An electrical leadthrough can also be provided in an insulating shaped part in a simple manner.
A particular embodiment in accordance with the invention is characterized in that the organic layer comprises an electroluminescent polymer. Electroluminescent polymers are suitable EL materials. They have good luminescent properties, a good conductivity and good film-forming properties. If use is made of simple techniques, such as spin coating, EL layers having a large surface area can be manufactured by means of these materials. Suitable polymers generally have a conjugated "backbone", such as soluble polyphenylenephenylenevinylenes, soluble poly-thiophenes and soluble poly-phenylenes. Polyphenylenevinylenes are very suitable EL materials. By means of substitution, in particular, in the 2- and 5-positions of the phenyl ring, the emission spectrum can be varied and readily soluble and processable variants can be obtained. In addition, said polymers are generally readily processable and yield amorphous layers. Polymers which are particularly suitable are 2,5 alkyl- and alkoxy-substituted poly-phenylenevinylenes.
Examples of particularly suitable poly-phenylenevinylenes are:
poly(2-methyl-5-(n-dodecyl)-p-phenylenevinylene)
poly(2-methyl-5-(3,7-dimethyloctyl)-p-phenylenevinylene)
poly(2-methyl-5-(4,6,6-trimethylheptyl)-p-phenylenevinylene)poly(2-methoxy-5-decyloxy-p-phenylenevinylene)
poly(2-methoxy-5-(2-ethylhexyloxy)-p-phenylenevinylene) (MEH-PPV).
The combination of the housing in accordance with the invention and an EL element whose organic EL layer comprises a 2,5-substituted poly(phenylenevinylene) is particularly advantageous, as experiments carried out by the inventors have shown that many poly(phenylenevinylene) variants already show degradation if they are exposed to temperatures of 80 to 100° C. for a long period of time.
These and other aspects of the invention will be apparent from and elucidated with reference to the embodiments described hereinafter.
BRIEF DESCRIPTION OF THE DRAWING
In the drawings:
FIG. 1 is a schematic, cross-sectional view of an embodiment of the EL device in accordance with the invention,
FIG. 2 is a schematic, cross-sectional view of a second embodiment of the EL device in accordance with the invention,
FIG. 3 is a schematic, plan view of a third embodiment of the EL device in accordance with the invention,
FIG. 4 is a schematic, cross-sectional view taken on the line I--I of the third embodiment of the EL device in accordance with the invention, and
FIG. 5 is a schematic, cross-sectional view of a fourth embodiment of the EL device in accordance with the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Exemplary Embodiment 1
FIG. 1 shows, in cross-section and not to scale, an EL device 1 in accordance with the invention. Said EL device comprises an EL element 2 which is composed of a positive, transparent electrode 3 which is entirely covered by an electroluminescent organic layer 4 which carries a negative electrode 5. Said EL element is enclosed in an airtight and waterproof housing 6. Said housing comprises a shaped part 7 of a transparent, electrically insulating material, which serves as the substrate for the EL element. The housing is sealed by a coating layer 8 of a low-melting metal alloy, which covers the entire EL element as well as regions of the shaped part 7 which adjoin the EL element. The coating layer 8 serves as an electrical connection for the negative electrode 5. Said coating layer 8 is provided with an electrically conducting bonding layer 9. The shaped part 7 is provided with an electrical leadthrough 10, which is connected to the positive electrode 3. The leadthrough 10 is surrounded by a bonding layer 11.
The EL device 1 can be manufactured as follows. In a nitrogen atmosphere, an aperture is formed in a glass plate, having dimensions of 2 cm by 1.5 cm and a thickness of 1 mm, which is provided with an 150 nm thick positive electrode 3 of indium tin oxide (supplier Balzers) by locally sandblasting a location where there is ITO. The walls of the aperture are coated with a silver-containing glass paste by means of a cotton bud, said paste being prepared by mixing 75 parts by weight of a mixture consisting of 8 wt. % lead-borate glass powder and 92 wt. % silver powder with 25 parts by weight of a mixture consisting of 50 wt. % alpha-terpineol and 50 wt. % ethylcellulose by means of a three-way roller. The glass paste is cured in a furnace at 450° C. for 30 minutes, thereby forming the bonding layer 11. The thickness of said bonding layer is approximately 30 micrometers. Subsequently, the aperture is filled with molten eutectic PbSn solder, which solidifies after cooling, thereby forming the electrical lead-through 10. Subsequently, the surfaces are cleaned by means of, respectively, soap, water and isopropanol. An approximately 150 nm thick organic EL layer 4 is provided by spin coating from an 0.6 wt. % solution of poly[2-methoxy-5-(2,7-dimethyloctyloxy)-1,4-phenylenevinylene], synthesized in accordance with the method described in Braun et. al., Synth. Met., 66 (1994), 75, in toluene. The EL material is removed along the edges by means of a cotton bud and/or a knife. Yb is vacuum deposited, via a mask, thereby forming a 200 nm thick negative electrode 5. An approximately 200 nm thick layer of nickel and a 200 nm thick layer of silver are successively provided by means of magnetron sputtering and vapor deposition, respectively, thereby forming the bonding layer 9. A 200 micrometer thick foil of Sn(50 wt. %)Pb(32 wt. %)Cd(18 wt. %) (supplier Witmetaal b.v.) having a melting point of 145° C. is applied to the bonding layer, the oxide skin of said foil being removed by scouring. The whole is placed on a hot plate of 155° C., so that the alloy melts and, after cooling, the coating layer 8 is obtained.
An EL device thus formed is immersed, in ambient conditions, in a water bath of 80° C. for approximately 10 seconds and, immediately afterwards, it is immersed in an ice bath for approximately 10 seconds. This procedure is repeated for 48 hours. After drying, a voltage of 6 V is applied to the electrodes 3 and 5, via leadthrough 10 and coating 8, so that the device emits orange light. The luminous surface does not exhibit "dark spots". The uniformity of the luminous surface is visibly equal to that of a control EL device without a housing, which is manufactured, and directly measured, in a nitrogen atmosphere.
Another EL device which is manufactured in this manner is subjected to a life test. In this test, the device is continuously operated for 400 hours under atmospheric conditions at a constant current density of 15 mA/cm 2 . The voltage necessary to attain a current density of 15 mA/cm 2 remains constant for 400 hours, which means that the resistance of the EL element does not change in time. The luminance, which is determined by means of a photodiode and a Keithley 617 electrometer initially amounts to 200 Cd/m 2 and decreases to 60 Cd/m 2 after 400 hours. The uniformity of the luminous surface, however, remains constant. The luminance decreases uniformly over the entire luminous surface. Even after 400 hours, not a single "dark spot" is observed. The EL efficiency of the EL device, which is determined in a calibrated "integrating sphere", initially amounts to 1.2% and decreases at the same rate as the luminance.
For comparison, a few similar EL devices are manufactured, in which the coating 8 and the bonding layer 9 are replaced by a layer of an epoxy adhesive. Dependent upon the type of epoxy and the manner of processing, the service life of the EL device is only several hours and "dark spots" are observed after a short time already.
Another EL device thus manufactured is subjected to a "shelf life" test. In this test, the EL device is stored under ambient conditions and the luminance and the current are measured at regular intervals at a voltage of 6 V. During at least 650 hours, the current remains substantially constant and amounts to 0.028 A, whereas the luminance decreases from 130 to 115 Cd/m 2 . Also in this case, the uniformity of the luminous surface is unchanged. The decrease in luminance takes place uniformly over the entire surface area. Also after 650 hours, the surface is still free of "dark spots".
Comparable results are achieved with EL devices in which the coating 8 consists of the low-shrinkage Bi(58 wt. %)Sn(42 wt. %) (supplier Arconium) or the ductile Sn(35.7 wt. %)Bi(35.7 wt. %)Pb(28.6 wt. %) (supplier Arconium) or indium.
Comparable results were achieved if the coating 8 was provided by dip coating in the following manner. After the provision of the bonding layer 9, the device is pre-heated on a hot plate of 155° C. and immersed for 10 seconds in a bath which is heated to 155° C. and which is filled with molten Sn(50 wt. %)Pb(32 wt. %)Cd(18 wt. %) (supplier Witmetaal B.V.). After removal from the bath and cooling, the housing is sealed by a 150 micrometer thick coating of said alloy.
Comparable results are also achieved if the organic layer comprises poly(2-methoxy-5-(2-ethylhexyloxy)-p-phenylenevinylene) (MEH-PPV) and if calcium is used for the negative electrode.
Exemplary Embodiment 2
FIG. 2 shows, in cross-section and not to scale, an EL device 21 in accordance with the invention. Said device is very similar to the EL device 1. However, in this case, the housing 26 comprises a shaped part 32 instead of the coating 8, which shaped part is connected by means of a closed ring of a low-melting metal alloy 28 to the shaped part 7 so as to enclose a hollow space 34. Between the ring 28 and the shaped part 7 there is the ring-shaped, electrically conducting bonding layer 29, and between the ring 28 and the shaped part 32 there is an additional bonding layer 33. Said ring 28 electrically contacts the electrode 5, electrically feeding this electrode.
The EL device 21 can be manufactured as follows. The method described in exemplary embodiment 1 is repeated up to and including the provision of the bonding layer 29, with this difference that the provision of the bonding layer 29 takes place via a mask, which covers the edges of the device so as to provide also a part of the electrode 5 with a bonding layer. Subsequently, the device is provided on all sides with a ring-shaped layer of Sn(50 wt. %)Pb(32 wt. %)Cd(18 wt. %) by means of dip coating in the manner described hereinabove, which layer will form a part of the closed ring 28. Due to differences in wettability between the bonding layer and the other parts of the surface, metal is deposited only on the bonding layer. Subsequently, a 1 mm thick glass plate 32 is provided with a correspondingly patterned bonding layer 33. Said bonding layer 33 is provided with a ring-shaped layer of Sn(50 wt. %)Pb(32 wt. %)Cd(18 wt. %) by means of dip coating, which layer will form a second part of the closed ring 28. Both parts are subsequently placed on a hot plate of 155° C., thereby causing the ring-shaped layers to melt. Next, the parts are provided on top of each other in such a manner that the ring-shaped layers fuse together so as to form one closed ring 28. Subsequently, the metal is allowed to solidify. As the entire process is carried out in nitrogen, the space 34 is filled with nitrogen.
Exemplary Embodiment 3
FIG. 3 is a plan view, not to scale, and FIG. 4 is a sectional view taken on the line I--I, not to scale, of an EL device 41 in accordance with the invention. Said EL device 41 is equal to device 1, with this difference that in the housing 46, the electrical leadthrough 10 is replaced by the electrical leadthrough 50 which electrically feeds the positive electrode 43 of the EL element 42, which element also comprises the organic EL layer 44 and the negative electrode 45. The electrical leadthrough 50 and the electrode 43 are formed from the same layer. The coating 48 of a low-melting metal is provided with a bonding layer 49 and separated from the electrical leadthrough 50 by the electrically insulating layer 51.
The EL device 41 can be manufactured as follows. A glass plate 7 which is covered with a 150 nm thick layer of ITO (supplier Balzers) (43,50) is cleaned, in succession, with soap, water and isopropanol. A lead-borate glass paste filled with ceramic materials (type LS0206, supplier Nippon Electric Glass Co. Ltd.) is screen printed onto the electrical leadthrough 50. After drying at 120° C. in air for 15 minutes, the temperature is slowly increased to 450° C., and a sintering process is carried out for 10 minutes thereby forming the airtight and waterproof electrical insulating layer 51. The EL device is completed by successively providing the EL layer 44, the negative electrode 45, the bonding layer 49 and the coating 48, as described in exemplary embodiment 1.
Exemplary Embodiment 4
FIG. 5 shows in cross-section and not to scale, an EL device 61 in accordance with the invention. Said device 61 is very similar to the EL device 41, with this difference that in the housing 66, the bonding layer 49 is replaced by the ring-shaped bonding layer 69 and the coating 48 is replaced by the ring of a low-melting metal 68, the shaped part 72 and the ring-shaped bonding layer 73, thereby enclosing the hollow space 76. The device further comprises an electrical leadthrough 74, which is electrically insulated from the closed ring 68 by the layer of a low-melting glass 75. | An organic electroluminescent device includes an electroluminescent element, which is enclosed in a housing. The deterioration in uniformity of the luminous surface, which occurs when an electroluminescent device is stored or operated under ambient conditions, and which deterioration manifests itself, for example, in the form of "dark spots", can be overcome to a substantial degree in accordance with the invention by using an airtight and waterproof housing which is sealed by a low-melting metal, such as a BiSn alloy. | 7 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention broadly relates to computer system migration tools, and the improvements thereof.
2. Background
Computer migration may be broadly defined as the process of transferring some or all of a “source” computer's information, non-device assets or intellectual property, to a “target” computer. The computer migration process is often carried out via a special computer migration tool kit in the form of software loaded on the source computer, the target computer, or both. The two computers involved in the migration process can be linked in a variety of ways, including, inter alia, direct cables/wires, direct telephone links, Local Area Networks (LANs), and Wide Area Networks (WANs). Alternatively, another approach is to use an intermediate storage device or system (e.g., rewritable or write-once CDs, ZIP® storage devices, network storage, etc.) to which to transfer aspects of the source computer. The aspects to be migrated are then transferred from the intermediate device to the target computer.
With rapid advancements in the computing power and memory capacity of widely available desktop computers, as well as others, the practical life cycle of computer systems continues to decrease. While users continue to switch to newer computer systems, there is very often a need and desire to transfer important aspects of the old computer system to the new computer system. There are several prior art approaches to computer migration, each having drawbacks. A “brute-force” approach entails painstakingly transferring software, data and other aspects of a source computer to a target computer in a piece-meal fashion. This method is tedious, extremely slow, and often requires a level of sophistication not possessed by ordinary computer users who wish to transfer important aspects from one computer to another computer.
An improved approach is to semi-automatically migrate aspects of a source computer to a target computer using a migration tool kit which has been loaded in the source computer, the target computer, or both. Using this approach, all non-physical aspects of source computer are transferred en masse. While this eliminates some of the drawbacks (i.e., tediousness, time consuming, difficult for ordinary users) of brute-force migration methods, there are yet problems with this approach. Often the user would like to transfer most of the aspects of the source computer, but not all of them—especially where newer versions of software and operating system are available. This approach can also transfer aspects from the source computer that may be incompatible with the target computer, leading to conflicts, dangerous system instability, and sometimes inoperability of the target computer.
Later generation software such as the Alohabob's™ PC Relocator software marketed by Eisenworld, Inc., the assignee of this Letters Patent, solves the aforementioned problems by transferring all of the important aspects of the source computer—including preferences and settings—to the target computer, while giving the user the option to leave behind potentially troublesome (to the target computer) aspects of the source computer.
Even with these improvements, the en masse transfer from the source computer to the target computer is not always desirable. Users sometimes wish to be given the choice of only transferring specific programs and related data. The typical prior art approach to transferring specific programs is a script-based approach, in which the migration tool responds directly to scripts stored in the migration software for the exact course of action to take regarding known software programs. This approach only works where the migration tool kit is set up to migrate the specific program in question. Thus, it may be possible to successfully migrate very popular software programs and data, but not less popular or more proprietary software programs and data. These tools have no mechanism to migrate aspects for which there are not already stored scripts.
A last ditch effort of the prior art approaches allows sophisticated users who are so inclined to develop their own scripts for programs that are not recognized by the original migration software. However, even if one is capable and motivated to generate scripts for programs not covered by the original migration software, there is no flexibility to handle new software on the fly.
What is therefore sorely needed is a migration tool which allows a user to conveniently transfer specific aspects of a source computer to a target computer that the user selects, and a migration tool that can intelligently and automatically transfer aspects of the source computer to the target computer, even when the migration tool has no previous knowledge of, or encounters with a particular program to be transferred.
SUMMARY OF THE INVENTION
In view of the aforementioned problems and deficiencies of the prior art, the present invention provides a computer migration method for transferring software programs from a source computer to a target computer. The method at least includes the steps of surveying the source computer assets, without scripts, associating portions of the source computer assets into source computer Application Groups on the fly, and generating a list at least including the source computer Application Groups. The method also at least includes the steps of receiving a user's selection of source computer Application Groups to be migrated to the target computer, and transferring source computer Application Groups selected to the target computer.
The present invention also provides a computer migration tool adapted for transferring software programs from a source computer to a target computer. The computer migration tool at least includes a source computer asset surveyor adapted to survey the source computer assets, a source computer application grouper adapted to, without scripts, associate portions of the source computer assets on the fly into source computer Application Groups, and a source computer list generator adapted to generate a list comprising the source computer Application Groups. The computer migration tool also at least includes a selection receiver adapted to receive a user's selection of source computer Application Groups to be migrated to the target computer, and an Application Group transferor adapted to transfer source computer Application Groups selected to the target computer.
BRIEF DESCRIPTION OF THE DRAWING FIGURES
Features and advantages of the present invention will become apparent to those skilled in the art from the description below, with reference to the following drawing figures, in which:
FIGS. 1A and 1B together, constitute a flowchart detailing the steps of the present-inventive migration method; and
FIG. 2 is an illustration of an interactive screen presented to the user of the present-inventive migration tool, showing the Application Groups being considered for migration, and the Confidence Levels (described infra) associated with each.
BRIEF DESCRIPTION OF THE APPENDICES
Appendix A includes the first 10 pages of an example of an installation log file for an installed program, which log file can be interpreted by the present-inventive migration tool; and
Appendix B includes an example of an uninstall log file for an installed program, which log file can be interpreted by the present-inventive migration tool.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The term “program” is used broadly in the specification and claims of this Letters Patent to include not only algorithms that make up software, but data associated with software. The algorithms may be associated with applications, operating systems, and other functions and aspects of computer systems.
FIGS. 1A and 1B , together, illustrate the basic algorithm 100 capable of being practiced by one skilled in the art to implement the present-inventive computer migration tool.
To summarize, the present-inventive migration tool groups, “on the fly,” all assets on a source computer into programs to be transferred to a target computer, and rather than relying upon scripts, relies upon predefined rules to decide the program association of assets encountered on the source computer.
The major steps in the present-inventive migration process are: 1) Scan the source computer to determine all of its assets; 2) Analyze the assets using predefined rules, and place them into Application Groups; 3) Perform a confidence analysis on each Application Group to designate a Confidence Level reflecting the likelihood that all of the actual components that are supposed to be included in an Application Group have in fact been so included; 4) Scan and analyze the target computer assets; 5) Present the migration tool user with a list of source computer Application Groups, along with their Confidence Levels established in Step 3, including a list of items not recommended for migration; 6) Transferring the items designated by the user from the source computer to the target computer; and 7) Creating and storing on both the source computer and the target computers, a log detailing the migration process undertaken.
Returning to FIG. 1A , the migration algorithm is begun at Step 102 by keystrokes or the manipulation of a pointing device. The first step ( 104 ) of the migration process is to ascertain all of the programs and assets of the source computer. Many different aspects of the source computer are scanned to accomplish this step. The following areas are scanned to find the programs and other items: Start Menus and related shortcuts; System Databases/Registries; Install and Uninstall log files; and the File System, including a full directory scan and a scan of likely application directories. The full directory scan includes known application directories, such as the “Program Files” directory. Examples of the application directory paths in Windows® based systems include “C:\<app directory>\,” where <app directory> contains executables/application files and is not a known Windows® directory.
Installation log files are stored on computers when certain well-known installation technologies are used. Installation log files contain a listing of all of the files installed that make up a particular program. An example of a portion of such an installation log file is found in Appendix A.
Supplemental to perusing installation files, the migration tool can also check for and review uninstall log files. Uninstall log files may also contain useful information about the files which make up a particular program. An example of such an uninstall log file is found in Appendix B.
Step 106 of the migration process groups applications by: Directory, Installer Entry, Common Start Menu Folders, Application Name, Magic Dates (such as the creation or modification dates of files), and File Allocation Tables. Next, the migration process packages the applications into Application Suites, Files and Directories, Registry Entries, Start Menu/Desktop Shortcut Entries, and Installer Entries (Step 108 ).
In carrying out Steps 106 and 108 the migration tool initiates a rules-based approach to determine with which program, each file belongs. The predefined rules are based on empirical observations and the probabilities that files stored, created, or modified in certain ways are associated with the same program. While they are a matter of design choice, the rules for interpreting the program association of files are easily established and implemented by those skilled in the art.
For example, the migration tool assumes that files found in the same folder are part of the same program. Empirical observations by the inventors of the present invention strongly support this assumption.
As another example, the migration tool can be implemented to assume (with a high degree of confidence) that files created contemporaneously are part of the same program. The migration tool can also assume (with a high degree of confidence) that files modified contemporaneously are part of the same program.
Another rules-based approach is implemented as follows: by examining file allocation tables, the migration tool can assume (again, with a high degree of confidence) that files stored in locations which are nearby are part of the same program. The relative “closeness” of the files is a matter of design choice.
The next step ( 110 ) performs a Confidence Analysis on the Application Groups to generate a Confidence Level measuring the relative confidence that all of the assets which belong to an Application Group (and none which do not properly belong) have in fact been included in the Application Group. In the preferred embodiment, the Confidence Level is an assigned ranking from zero (0) percent to one hundred (100) percent (Step 112 ). More particularly, the confidence ranking is based upon such factors as whether all of the expected registry entries exist, whether all expected menu entries exist, whether all files are grouped in the expected directory folder or sub-folder, and whether installation or uninstallation log files exist.
The Confidence Level assigned in Step 112 is optimized in Step 114 . Optimization involves comparing the information about the Application Groups to the knowledge base of the migration tool. Optimization also involves checking the “magic dates” of the files making up the Application Groups. Magic dates include such dates as the installation, creation, modification and uninstallation dates of files. The file allocation tables are also used to optimize the Confidence Level.
In the preferred embodiment, neither hardware specific drivers and software, nor items that are part of the operating system are transferred to the target computer unless the user specifically requests such a transfer. It has been found by the inventors that such files often cause noteworthy problems when transferred to target computers that are not identical to the source computers. Therefore, such items are rejected for migration in Step 116 .
In Step 118 , the target computer is scanned and analyzed in the same manner as was the source computer in Steps 104 - 108 , so that the migration tool is aware of the Application Groups and items on both the source and target computers. This is followed by Step 120 , which rejects software that may cause instability in the target computer operating system (e.g., operating system utilities).
While certain items will be rejected by the migration tool in Steps 116 and 120 , there are other items which should be brought to the attention of the migration tool user as being suspect for migration. These are flagged in Step 122 , and include: any ambiguous items; software that already exists on the target computer; and software that may not completely transfer from the source computer to the target computer.
Step 124 provides a user-friendly display with a list of Application Groups and other items on the source computer and their associated Confidence Levels, as well as destination locations on the target computer. Using the information from the display and a pointing device, the migration tool user can then make an informed decision about the items he or she wishes to migrate from the source computer to the target computer.
FIG. 2 illustrates an example of a display 200 presented in Step 124 . In this example, the applications and items to be considered for migration are in the middle of the display. A Confidence section appears on the left, and includes transfer recommendation boxes, the Confidence Level of the Application Group or item, and a confidence bar reflecting the transfer recommendation. The target computer destination directory is listed on the right side of the display.
In the preferred embodiment, the confidence bars indicate by color, the Confidence Level. Much like a traffic signal, a green bar indicates that the item can be migrated without causing any problems in the target computer, a red bar indicates that the item should not be migrated, and a yellow bar urges caution in migrating the item (i.e., it is unclear whether migration of the item will cause problems in the target computer). Other approaches can be used instead of, or complimentary to, the color scheme of the confidence bars. For example, a full-length bar can indicate a 100 percent Confidence Level, while the shortest possible bar (or none at all in the alternative) can indicate a 0 percent Confidence Level.
When all of the programs and files are chosen for migration, and in response to the user's command, the migration tool transfers all of the designated programs and files from the source computer to the target computer (Step 126 ).
The last step ( 128 ) before the end (Step 130 ) of the migration algorithm creates and stores a migration log file detailing the completed migration process. In the preferred embodiment, duplicate migration log files are stored on both the source computer and target computer.
Variations and modifications of the present invention are possible, given the above description. However, all variations and modifications which are obvious to those skilled in the art to which the present invention pertains are considered to be within the scope of the protection granted by this Letters Patent.
For example, the present invention can be combined with a script-based approach for well-known software programs to be migrated, while relying upon the novel features described supra, for software programs that are not well-known, or are proprietary in nature.
It should also be understood that the novel teachings of the present invention can be utilized regardless of the size or complexity of the source and target computers (i.e., PC-to-PC migrations, mainframe-to-mainframe migrations, combinations or gradations of these, as well as migrations where one or more special purpose digital device is involved are all applicable). | A computer migration method for transferring non-physical aspects from a source computer to a target computer according to an embodiment. In one embodiment, the method includes surveying the source computer aspects, and without scripts, associating portions of the source computer aspects into source computer Application Groups on the fly. The method also includes generating a list at least including the source computer Application Groups; receiving a user's selection of source computer Application Groups to be migrated to the target computer; and transferring selected source computer Application Groups to the target computer,; wherein the target computer is adapted to supplant the source computer after migration. | 6 |
FIELD OF THE INVENTION AND RELATED ART STATEMENT
This invention relates to a method for the removal of CO 2 (carbon dioxide) present in CO 2 -containing gases such as combustion exhaust gas. More particularly, it relates to a method for the efficient removal of CO 2 present in gases by using an aqueous solution containing a specific amine compound.
Conventionally, investigations have been made on the recovery and removal of acid gases (in particular, CO 2 ) contained in gases (i.e., gases to be treated) such as natural gas, various industrial gases (e.g., synthesis gas) produced in chemical plants, and combustion exhaust gas, and a variety of methods therefor have been proposed. In the case of combustion exhaust gas taken as an example, the method of removing and recovering CO 2 present in combustion exhaust gas by bringing the combustion exhaust gas into contact with an aqueous solution of an alkanolamine or the like, and the method of storing the recovered CO 2 without discharging it into the atmosphere are being vigorously investigated.
Although useful alkanolamines include monoethanolamine, diethanolamine, triethanolamine, methyldiethanolamine, diisopropanolamine, diglycolamine and the like, it is usually preferable to use monoethanolamine (MEA).
However, the use of an aqueous solution of such an alkanolamine, typified by MEA, as an absorbent for absorbing and removing CO 2 present in combustion exhaust gas is not always satisfactory in consideration of the amount of CO 2 absorbed for a given amount of an aqueous amine solution having a given concentration, the amount of CO 2 absorbed per mole of the amine in an aqueous amine solution having a given concentration, the rate of CO 2 absorption at a given concentration, and the thermal energy required for regeneration of the aqueous alkanolamine solution having absorbed CO 2 .
Now, many techniques for separating acid gases from various mixed gases by use of an amine compound are known, and examples thereof are given below.
In Japanese Patent Laid-Open No. 100180/'78, there is described a method for the removal of acid gases wherein a normally gaseous mixture is brought into contact with an amine-solvent liquid absorbent composed of (1) an amine mixture comprising at least 50 mole % of a hindered amine having at least one secondary amino group forming a part of the ring and attached to a secondary or tertiary carbon atom, or a primary amino group attached to a tertiary carbon atom, and at least about 10 mole % of a tertiary amino-alcohol, and (2) a solvent for the aforesaid amine mixture which serves as a physical absorbent for acid gases. It is stated therein that useful hindered amines include 2-piperidine-ethanol i.e., 2-(2-hydroxyethyl)piperidine!, 3-amino-3-methyl-1-butanol and the like, and useful solvents include sulfoxide compounds which may contain up to 25% by weight of water. As an example of the gas to be treated, a normally gaseous mixture containing high concentrations of carbon dioxide and hydrogen sulfide (e.g., 35% CO 2 and 10-12% H 2 S) is described therein. Moreover, CO 2 itself is used in some examples of this patent.
In Japanese Patent Laid-Open No. 71819/'86, an acid gas scrubbing composition comprising a hindered amine and a nonaqueous solvent such as sulfolane is described. In this patent, the usefulness of hindered amines for the absorption of CO 2 is explained with the aid of reaction formulas.
The carbon dioxide absorption behavior of an aqueous solution containing 2-amino-2-methyl-1-propanol (AMP) as a hindered amine is disclosed in Chemical Engineering Science, Vol. 41, No. 4, pp. 997-1003. CO 2 and a CO 2 -nitrogen mixture at atmospheric pressure are used as gases to be treated.
The rates of CO 2 and H 2 S absorption by an aqueous solution of a hindered amine (such as AMP) and an aqueous solution of a straight-chain amine (such as MEA) in the vicinity of ordinary temperature are reported in Chemical Engineering Science, Vol. 41, No. 2, pp. 405-408.
U.S. Pat. No. 3,622,267 discloses a technique for purifying synthesis gas obtained by partial oxidation of crude oil or the like and having a high partial pressure of CO 2 (e.g., synthesis gas containing 30% CO 2 at 40 atmospheres) by use of an aqueous mixture containing methyldiethanolamine and monoethylmonoethanolamine.
Deutsche Offenlegungschrift Nr. 1,542,415 discloses a technique for enhancing the rate of CO 2 , H 2 S and COS absorption by the addition of a monoalkylalkanolamine or the like to physical or chemical absorbents. Similarly, Deutsche Offenlegungschrift Nr. 1,904,428 discloses a technique for enhancing the absorption rate of methyldiethanolamine by the addition of monomethylethanolamine.
U.S. Pat. No. 4,336,233 discloses a technique for the purification of natural gas, synthesis gas and gasified coal by use of a washing fluid comprising an aqueous solution containing piperazine at a concentration of 0.81-1.3 moles per liter or an aqueous solution containing piperazine in combination with a solvent such as methyldiethanolamine, triethanolamine, diethanolamine or monomethylethanolamine.
Similarly, Japanese Patent Laid-Open No. 63171/'77 discloses a CO 2 absorbent comprising a tertiary alkanolamine, monoalkylalkanolamine or the like to which piperazine or a piperazine derivative such as hydroxyethylpiperazine is added as a promoter.
As described above, an efficient method for the removal of CO 2 from various CO 2 -containing gases is desired. In particular, it is a pressing important problem to choose a CO 2 absorbent (amine compound) which, when a gas is treated with an aqueous solution containing the absorbent at a given concentration, can give a large amount of CO 2 absorbed per mole of the-absorbent, a large amount of CO 2 absorbed per unit volume of the aqueous solution, and a high absorption rate. Moreover, it is desirable that the absorbent requires less thermal energy in separating the absorbed CO 2 to regenerate the absorbing solution. It may be difficult to meet all of these requirements by using a single amine compound. However, if an amine compound meeting some requirements is found, it may be possible to meet a more desirable combination of requirements, for example, by mixing it with one or more other amine compounds. That is, if an amine compound capable of giving, for example, a large amount of CO 2 absorbed per mole of the absorbent, it may be possible to improve its absorption rate and other properties separately.
In view of the above-described existing state of the prior art, it is an object of the present invention to provide an efficient method for the removal of CO 2 from CO 2 -containing gases by using a novel amine compound which can give a large amount of CO 2 absorbed per mole of the absorbent and has the property of liberating the absorbed CO 2 easily.
SUMMARY OF THE INVENTION
In order to solve the above-described problems, the present inventors made intensive investigations on absorbents used to remove CO 2 present in combustion exhaust gas and have now discovered that an aqueous solution of a specific amine compound has great CO 2 -absorbing power and permits the absorbed CO 2 to be easily liberated. The present invention has been completed on the basis of this discovery. That is, the present invention has the following two aspects.
According to a first aspect of the present invention, there is provided a method for the removal of CO 2 present in gases which comprises bringing a CO 2 -containing gas into contact with an aqueous solution containing at least one amine compound of the general formula 1! ##STR2## wherein R 1 to R 8 may be the same or different and each represent a hydrogen atom or an alkyl group of 1 to 4 carbon atoms, and m is 0 or 1.
According to a second aspect of the present invention, there is provided a method for the removal of CO 2 present in gases which comprises bringing a CO 2 -containing gas into contact with an aqueous solution containing at least one amine compound of the above general formula 1! and at least one other amine compound having great CO 2 -absorbing power.
When an aqueous solution containing an amine compound of the general formula 1! is used as an absorbing solution according to the method of the present invention, the amount of CO 2 liberated per mole of the absorbent is increased as compared with the case where a conventional absorbing solution is used. Thus, CO 2 can be removed more efficiently.
Moreover, since the amine compound of the general formula 1! permits the absorbed CO 2 to be easily desorbed by heating the absorbing solution having absorbed CO 2 , less thermal energy is required to regenerate the absorbing solution. Thus, a process having a smaller overall energy consumption for the recovery of CO 2 can be constructed.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a flow diagram illustrating an exemplary process for the removal of CO 2 present in combustion exhaust gas to which the method of the present invention can be applied; and
FIG. 2 is a graph showing changes with time of the CO 2 concentration in the absorbing solution as observed in the CO 2 desorption tests of Example 1 and Comparative Example 1.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
In the amine compounds of the general formula 1! which can be used in the present invention, R 1 to R 8 may be the same or different and each represent a hydrogen atom or an alkyl group of 1 to 4 carbon atoms. Specific examples of the alkyl group of 1 to 4 carbon atoms include methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl and tert-butyl groups. Among others, it is preferable to use a combination of alkyl groups in which the sum of the numbers of carbon atoms of R 1 and R 2 and the sum of the numbers of carbon atoms of R 5 and R 6 are 4 or less and the sum of the numbers of carbon atoms of R 3 and R 4 and the sum of the numbers of carbon atoms of R 7 and R 8 are 2 or less. Amine compounds of the general formula 1! may be used alone or in admixture of two or more.
Specific examples of amine compounds of the general formula 1! include 2-aminopropionamide H 2 NCH(CH 3 )CONH 2 !, 2-amino-2-methylpropionamide H 2 NC(CH 3 ) 2 CONH 2 !, 3-amino-3-methylbutylamide H 2 NC(CH 3 ) 2 CH 2 CONH 2 !, 2-amino-2-methyl-N-methylpropionamide H 2 NC(CH 3 ) 2 CONH( CH 3 )!, 3-amino-3-methyl-N-methylbutylamide H 2 NC(CH 3 ) 2 CH 2 CONH(CH 3 )!, 3-amino-3-methyl-N,N-dimethylbutylamide H 2 NC(CH 3 ) 2 CH 2 CON(CH 3 ) 2 !, 2-ethylaminoacetamide (H 5 C 2 )NHCH 2 CONH 2 !, 2-(t-butylamino)acetamide (tert-H 9 C 4 )NHCH 2 CONH 2 !, 2-dimethylamino-N,N-dimethylacetamide (CH 3 ) 2 NCH 2 CON(CH 3 ) 2 !, 2-ethylamino-2-methylpropionamide (H 5 C 2 )NHC(CH 3 ) 2 CONH 2 !, 3-ethylaminopropionamide (H 5 C 2 )NHCH 2 CH 2 CONH 2 !, 3-ethylaminobutylamide (H 5 C 2 )NHCH(CH 3 )CH 2 CONH 2 !, 3-ethylamino- 3 methylbutylamide (H 5 C 2 )NHC(CH 3 ) 2 CH 2 CONH 2 !, 2-diethylaminoacetamide (H 5 C 2 ) 2 NCH 2 CONH 2 !, 2-diethylaminopropionamide (H 5 C 2 ) 2 NCH(CH 3 )CONH 2 !, 2-diethylamino-2-methylpropionamide (HC 2 ) 2 NC(CH 3 ) 2 CONH 2 ! and 3-diethylamino-3-methylbutylamide (H 5 C 2 ) 2 NC(CH 3 ) 2 CH 2 CONH 2 !.
In the aqueous solution containing at least one amine compound as described above (hereinafter also referred to as the absorbing solution), which is used for contact with a CO 2 -containing gas according to the present invention, the concentration of the amine compound is usually in the range of 15 to 65% by weight and preferably 30 to 50% by weight. The temperature at which the absorbing solution is brought into contact with a CO 2 -containing gas is usually in the range of 30 to 70° C.
If necessary, the absorbing solution used in the present invention may further contain corrosion inhibitors, deterioration inhibitors and the like.
Moreover, in order to enhance the CO 2 -absorbing power (e.g., the amount of CO 2 absorbed and the absorption rate) of the absorbing solution, one or more other amine compounds having great CO 2 -absorbing power may be used in addition to the amine compound of the above general formula 1!. Preferred examples of the other amine compounds used for this purpose include monoethanolamine, 2-methylaminoethanol, 2-ethylaminoethanol, 2-isopropylaminoethanol, 2-n-butylaminoethanol, piperazine, 2-methylpiperazine, 2,5-dimethylpiperazine, piperidine and 2-piperidine-ethanol. Where these other amine compounds are used, they are usually used at a concentration of 1.5 to 50% by weight and preferably 5 to 40% by weight, provided that they are soluble in water together with the amine compound of the general formula 1!.
The gases which can be treated in the present invention include natural gas, various industrial gases (e.g., synthesis gas) produced in chemical plants, combustion exhaust gas and the like. Among others, the method of the present invention can be applied to gases under atmospheric pressure and, in particular, combustion exhaust gas under atmospheric pressure. As used herein, the term "atmospheric pressure" comprehends a deviation from atmospheric pressure which may be caused by using a blower or the like to feed combustion exhaust gas.
The present invention is more specifically explained below in connection with an illustrative case in which the gas to be treated comprises combustion exhaust gas. Although no particular limitation is placed on the process employed in the removal of CO 2 present in combustion exhaust gas according to the method of the present invention, one example thereof is described with reference to FIG. 1. In FIG. 1, only essential equipment is illustrated and incidental equipment is omitted.
The equipment illustrated in FIG. 1 includes a decarbonation tower 1, a lower packed region 2, an upper packed region or trays 3, a combustion exhaust gas inlet port 4 to the decarbonation tower, a decarbonated combustion exhaust gas outlet port 5, an absorbing solution inlet port 6, a nozzle-7, an optionally installed combustion exhaust gas cooler 8, a nozzle 9, a packed region 10, a humidifying and cooling water circulating pump 11, a make-up water supply line 12, a CO 2 -loaded absorbing solution withdrawing pump 13, a heat exchanger 14, an absorbing solution regeneration tower (hereinafter abbreviated as "regeneration tower") 15, a nozzle 16, a lower packed region 17, a regenerative heater (or reboiler) 18, an upper packed region 19, a reflux water pump 20, a CO 2 separator 21, a recovered CO 2 discharge line 22, a regeneration tower reflux condenser 23, a nozzle 24, a regeneration tower reflux water supply line 25, a combustion 20 exhaust gas feed blower 26, a cooler 27 and a regeneration tower reflux water inlet port 28.
In FIG. 1, combustion exhaust gas is forced into combustion exhaust gas cooler 8 by means of combustion exhaust gas feed blower 26, humidified and cooled in packed region 10 by contact with humidifying and cooling water from nozzle 9, and then conducted to decarbonation tower 1 through combustion exhaust gas inlet port 4. The humidifying and cooling water which has come into contact with the combustion exhaust gas is collected in the lower part of combustion exhaust gas cooler 8 and recycled to nozzle 9 by means of pump 11. Since the humidifying and cooling water is gradually lost by humidifying and cooling the combustion exhaust gas, make-up water is supplied through make-up water supply line 12.
In the lower packed region 2 of decarbonation tower 1, the combustion exhaust gas forced thereinto is brought into counterflow contact with an absorbing solution having a predetermined concentration and sprayed from nozzle 7. Thus, CO 2 present in the combustion exhaust gas is removed by absorption into the absorbing solution supplied through absorbing solution inlet port 6. The decarbonated combustion exhaust gas passes into upper packed region 3. The absorbing solution supplied to decarbonation tower 1 absorbs CO 2 and the resulting heat of reaction usually makes the absorbing solution hotter than its temperature at absorbing solution inlet port 6. The absorbing solution which has absorbed CO 2 is withdrawn by CO 2 -loaded absorbing solution withdrawing pump 13, heated in heat exchanger 14, and then introduced into absorbing solution regeneration tower 15. The temperature of the regenerated absorbing solution can be regulated by heat exchanger 14 or cooler 27 which is optionally installed between heat exchanger 14 and absorbing solution inlet port 6.
In absorbing solution regeneration tower 15, the absorbing solution is regenerated through heating by regenerative heater 18. The regenerated absorbing solution is cooled by heat exchanger 14 and optionally installed cooler 27, and returned to the absorbing solution inlet port 6 of decarbonation tower 1. In the upper part of absorbing solution regeneration tower 15, CO 2 separated from the absorbing solution is brought into contact with reflux water sprayed from nozzle 24, cooled by regeneration tower reflux condenser 23, and introduced into CO 2 separator 21 where CO 2 is separated from reflux water obtained by condensation of water vapor entrained thereby and then conducted to a CO 2 recovery process through recovered CO 2 discharge line 22. Part of the reflux water is recycled to absorbing solution regeneration tower 15 through nozzle 24 by means of reflux water pump 20, while the remainder is supplied to the upper part of decarbonation tower 1 through regeneration tower reflux water supply line 25.
The present invention is further illustrated by the following examples.
EXAMPLE 1
A glass reactor placed in a thermostatic chamber was charged with 50 milliliters of a 1 mole/liter (13 wt. %) aqueous solution of diethylaminoacetamide DEAAA; (H 5 C 2 ) 2 NCH 2 CONH 2 ! as an absorbing solution. While this absorbing solution was being stirred at a temperature of 40° C., CO 2 gas was passed therethrough under atmospheric pressure at a flow rate of 1 liter per minute for 1 hour. During this test, CO 2 gas was supplied through a filter so as to facilitate bubble formation.
After 1 hour, the amount of CO 2 contained in the absorbing solution was measured with a CO 2 analyzer (or total organic carbon analyzer), and the degree of CO 2 absorption (i.e., the molar ratio of CO 2 to the absorbing solution) was determined. Next, the reactor holding the absorbing solution was heated at 100° C. to examine the ease of desorption of CO 2 from the absorbing solution at 100° C. To this end, small amounts of samples of the absorbing solution heated at 100° C. were taken with the lapse of time and their CO 2 contents were measured with a CO 2 analyzer.
COMPARATIVE EXAMPLE 1
An absorption/desorption test was carried out with a 1 mole/liter (12 wt. %) aqueous solution of 2-diethylaminoethanol DEAE; (H 5 C 2 )NCH 2 CH 2 OH! having an analogous chemical formula. The results thus obtained are shown in Table 1 and FIG. 2.
TABLE 1______________________________________ CO.sub.2 content CO.sub.2 contentComponent after ab- after Amount ofof sorption heating CO.sub.2 libera-absorbing (A) (B) ted (A-B)solution mole %! mole %! %!______________________________________Example 1 DEAAA 62.9 2.3 60.6Compara- DEAE 99.9 44.8 55.1tiveExample 1______________________________________
It can be seen from the results shown in Table 1 and FIG. 2 that, when an aqueous solution of diethylaminoacetamide (DEAAA) that is an amine compound in accordance with the present invention is used as an absorbing solution for CO 2 gas, the amount of CO 2 absorbed per mole of the absorbent is somewhat smaller than when an aqueous solution of DEAE is used, but the amount of CO 2 liberated is larger than when an aqueous solution of DEAE is used because of the ease of desorption of CO 2 from the absorbing solution, thus making it possible to remove CO 2 efficiently.
EXAMPLES 2-3 AND COMPARATIVE EXAMPLE 2
Absorption/desorption tests for CO 2 gas were carried out in the same manner as in Example 1, except that the aqueous solution of DEAAA was replaced by a 1 mole/liter (10 wt. %) aqueous solution of 2-(t-butylamino)acetamide t-BAAA; (tert-H 9 C 4 )NHCH 2 CONH 2 ! (Example 2) or a 1 mole/liter (13 wt. %) aqueous solution of 2-dimethylamino-N,N-dimethylacetamide DMADMAA; (CH 3 ) 2 NCH 2 CON(CH 3 ) 2 ! (Example 3). Moreover, an absorption/desorption test was carried out with a 1 mole/liter (9 wt. %) aqueous solution of 2-ethylaminoethanol (EAE) (Comparative Example 2). The results thus obtained are shown in Table 2.
TABLE 2______________________________________ CO.sub.2 content CO.sub.2 contentComponent after ab- after Amount ofof sorption heating CO.sub.2 libera-absorbing (A) (B) ted (A-B)solution mole %! mole %! %!______________________________________Example 2 t-BAAA 89.3 10.9 78.4Example 3 DMADMAA 86.2 8.5 77.7Compara- EAE 92.5 39.1 53.4tiveExample 2______________________________________
It can be seen from the results shown in Table 2 that, when an aqueous solution of 2-(t-butylamino)acetamide (t-BAAA) or 2-dimethylamino-N,N-dimethylacetamide (DMADMAA) that is an amine compound in accordance with the present invention is used as an absorbing solution for CO 2 gas, the amount of CO 2 absorbed per mole is somewhat smaller than when an aqueous solution of EAE is used, but the amount of CO 2 liberated is larger than when an aqueous solution of EAE is used because of the ease of desorption of CO 2 from the absorbing solution, thus making it possible to remove CO 2 efficiently. | This invention provides a method for the removal of carbon dioxide present in gases which comprises bringing a CO 2 -containing gas into contact with an aqueous solution containing at least one amine compound of the general formula 1! ##STR1## wherein R 1 to R 8 may be the same or different and each represent a hydrogen atom or an alkyl group of 1 to 4 carbon atoms, and m is 0 or 1. The method of the present invention makes it possible to remove carbon dioxide efficiently. In particular, since carbon dioxide can be easily desorbed by heating the aqueous solution having absorbed carbon dioxide, the thermal energy required for regeneration of the aqueous solution can be reduced. | 1 |
This application is a divisional of prior U.S. patent application Ser. No. 11/514,139, filed Sep. 1, 2006 now abandoned, which is a continuation of prior U.S. patent application Ser. No. 10/922,153, filed Aug. 20, 2004 now U.S. Pat. No. 7,168,481, which claimed priority to Japanese Patent Application No. 2003-295841, filed Aug. 20, 2003, the entire contents of which are incorporated herein by reference.
BACKGROUND OF THE INVENTION
This invention relates to heat exchangers that have the heat exchanging section composed of ceramic blocks and which are applicable to wide areas including the atomic industry, aerospace, industries in general, and consumers use.
No corrosion-resistant materials have heretofore been available that enable concentrated sulfuric acid solutions to be vaporized and hydrogen iodide solutions to be vaporized and decomposed under high-temperature (>1000° C.) and high-pressure (>6 MPa) conditions; heat exchangers for such purposes have also been unavailable. To date, several ceramics manufacturers have made attempts to fabricate heat exchangers for high-temperature operation by using ceramic blocks but all failed to make large enough equipment on account of inadequacy in the strength of the blocks.
SUMMARY OF THE INVENTION
An object, therefore, of the present invention is to provide a heat exchanger that withstands heat exchange in large capacities ranging from several tens to a hundred megawatts in high-temperature (>1000° C.) and high-pressure (>6 MPa) environments of strong acids and halides in a solution as well as a gaseous phase and which yet can be fabricated in a compact configuration.
According to the present invention, ceramic materials that are highly resistant to strong acids such as concentrated sulfuric acid and halides such as hydrogen iodide are employed to make block elements through which a large number of circular ingress channels extend in perpendicular directions; by joining such block elements and piling them in the heat exchanging medium section, the invention provides a compact heat-exchanger that excels not only in corrosion resistance but also in high-temperature strength.
The compact heat exchanger of the invention which withstands high temperature (˜1000° C.) and high pressure as well as exhibiting high corrosion resistance can also be used as an intermediate heat exchanger in hot gas furnaces.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows the concept of a nuclear thermochemical IS plant;
FIG. 2 shows the design concept of a concentrated sulfuric acid vaporizer in actual operation;
FIG. 3 shows the shapes of ceramic blocks and experimentally fabricated ceramic pillars;
FIG. 4 shows a method of fabricating a ceramic pillar;
FIG. 5 shows individual ceramic blocks which are joined in a plurality of pillars and then bundled together to form a heat exchanging section;
FIG. 6 shows how ceramic pillars are eventually bundled together and how they are combined with section plates and partition plates to establish helium passageways;
FIG. 7 shows how section plates and partition plates are assembled;
FIG. 8 shows ceramic flow rate regulating plates as attached to the top and bottom of the fabricated heat exchanging section;
FIG. 9 shows reinforcing rings as subsequently attached to the fabricated heat exchanging section;
FIG. 10 shows the heat exchanging section as it is tightened by means of tie rods;
FIG. 11 shows the installation of inner tubes;
FIG. 12 shows how a pressure vessel for accommodating the heat exchanging section is assembled;
FIG. 13 shows how the heat exchanging section is installed within the pressure vessel;
FIG. 14 shows earthquake-resistant structures as they are fitted between the pressure vessel and the heat exchanging section;
FIG. 15 shows how a top reflector and helium inlet bellows are attached;
FIG. 16 shows a top cover as it is fitted on the pressure vessel;
FIG. 17 shows a mechanical seal as it is fitted on the pressure vessel;
FIG. 18 shows the autoclave employed in a high-temperature, high-pressure corrosion test; and
FIG. 19 shows the results of the high-temperature, high-pressure corrosion test conducted on various ceramics and refractory alloys.
DETAILED DESCRIPTION OF THE INVENTION
The invention provides a heat exchanger essential for realizing commercialization of a nuclear thermochemical IS plant that can produce large quantities of hydrogen and oxygen from the water feed using nuclear heat with 950° C. FIG. 1 shows the concept of a nuclear thermochemical IS plant. Among the various components shown, those which are operated under the most rigorous conditions are the sulfuric acid vaporizer and the hydrogen iodide decomposer.
FIG. 1 shows the concept of a nuclear thermochemical IS plant; the reaction involved is such that using the hot thermal energy of 850° C. as supplied from the hot gas furnace, water as the feed is decomposed into hydrogen and oxygen primarily through the combination of a sulfuric acid decomposing and regenerating cycle with a hydrogen iodide decomposing and synthesizing cycle.
To be more specific, H 2 O as supplied into the Bunsen reactor is decomposed under high-temperature, high-pressure conditions in the presence of both H 2 SO 4 and HI. After the reaction, the liquid portion containing H 2 SO 4 and HI is supplied into the acid separator where it is separated into two layers of H 2 SO 4 and HI. The HI containing solution passes through the purifier to be supplied into the distillation column; the resulting HI vapor is decomposed in the HI decomposer and the product H 2 is recovered from the condenser. The distillation residue in the distillation column and the condensate in the condenser are returned to the reactor.
The H 2 SO 4 containing solution coming from the acid separator passes through the purifier to be supplied into the concentrator and the concentrated H 2 SO 4 solution is subjected to vaporization in the H 2 SO 4 vaporizer; the resulting vapor is fed into the H 2 SO 4 decomposer, where it is decomposed into SO 2 , H 2 O and O 2 , which then pass through the condenser to return to the Bunsen reactor.
FIG. 2 shows the design concept of a concentrated sulfuric acid vaporizer in actual operation. A concentrated sulfuric acid solution is supplied from the furnace bottom of the vaporizer toward the upper arm, whereas helium gas with 689° C. is introduced laterally through the upper arm of the vaporizer; the two feeds are respectively guided to the perpendicular channels through each of the ceramic blocks in the vaporizer, where they undergo heat exchange until the concentrated sulfuric acid is completely gasified.
FIG. 3 shows the shapes of ceramic blocks and experimentally fabricated ceramic pillars. Individual blocks are piled up along the four sides of the cross-shaped perforated section plate provided through the center of the sulfuric acid vaporizer shown in FIG. 2 and they are held in position as the sulfuric acid feed is flowed upward through six or nine channels (holes) opened in two sides of each block. The hot helium gas feed is flowed laterally through four channels (holes) opened in a side of each block, whereby the sulfuric acid is heated via each block. The two groups of channels are formed in the block in such a way that they do not communicate with each other.
FIG. 4 shows a method of fabricating a ceramic pillar by stacking a plurality of ceramic blocks. As shown, a sufficient number of blocks to form a pillar are vacuum sealed into a metal vacuum chamber and heated from the outside, so that the blocks are joined one on top of another by means of brazing sheets to form a single pillar.
FIG. 5 shows individual ceramic blocks which are joined in a plurality of pillars and then bundled together to form a heat exchanging section.
FIG. 6 shows how ceramic pillars are eventually bundled together and how they are combined with section plates and partition plates to establish helium passageways.
FIG. 7 shows how section plates and partition plates are assembled, with four ceramic blocks being inserted and fixed in the center between adjacent partition plates.
FIG. 8 shows ceramic flow rate regulating plates as attached to the top and bottom of the fabricated heat exchanging section and FIG. 9 shows reinforcing rings as subsequently attached to the fabricated heat exchanging section.
FIG. 10 shows the individual constituent elements of the heat exchanging section as they are tightened by means of tie rods.
FIG. 11 shows the installation of inner tubes on side walls of the heat exchanging section that has been tightened by the tie rods.
FIG. 12 shows that a pressure vessel for accommodating the heat exchanging section is assembled as shown.
FIG. 13 shows how the heat exchanging section is installed within the pressure vessel after it has been assembled as shown in FIG. 12 .
FIG. 14 shows earthquake-resistant structures as they are fitted between the pressure vessel and the heat exchanging section.
FIG. 15 shows how a top reflector and helium inlet bellows are attached to the heat exchanging section as it has been mounted in the pressure vessel with the aid of the earthquake-resistant structures.
FIGS. 16 and 17 shows a top cover and a mechanical seal, respectively, as they are fitted on the pressure vessel to complete a heat exchanger for sulfuric acid.
EXAMPLE
(A) Design Concept of a Ceramic Compact Concentrated Sulfuric Acid Vaporizer and Experimental Fabrication of Individual Elements
Table 1 shows the design specifications of a concentrated sulfuric acid vaporizer for use in a nuclear thermochemical IS plant in actual operation that can be connected to a hot gas furnace of 200 MW. FIG. 2 shows the design concept of the concentrated sulfuric acid vaporizer.
TABLE 1 Specifications of Sulfuric Acid Vaporizer in Actual Operation Hydrogen production rate 25,514 N 3 /h Heat load on vaporizer 63 MV Heating helium gas In/out temperature 689° C./486° C. Flow rate 1.2 × 10 8 Nm 3 /h Process In/out temperature 455° C./486° C. Inlet H 2 O/(L/G) 363/816 kmol/h H 2 SO 4 (L/G) 1552/408 kmol/h Total 3139 kmol/h Outlet H 2 O/(L/G) 0/1178 kmol/h H 2 SO 4 (L/G) 0/1949 kmol/h Total 70,045 Nm 3 /h Heat exchange Δt1 203° C. Δt2 31° C. LMTD 92° C. Heat transfer coefficient 400 kcal/m 2 ° C. (as assumed) Pressure Helium inlet/H 2 SO 4 inlet 3 MPa/2 MPa
[How to Assemble the Concentrated Sulfuric Vaporizer]
(i) Fabricate a plurality of ceramic blocks (see FIG. 3 ) in each of which helium channels cross concentrated sulfuric acid solution channels at right angles. (ii) Fabricate a ceramic block pillar as shown in FIG. 4 by vacuum sealing into a metallic vacuum chamber a sufficient number of ceramic blocks to form a pillar and heating the blocks from the outside. (iii) Join individual ceramic blocks in a plurality of pillars and bundle them together as shown in FIG. 5 to form a heat exchanging section. (iv) Eventually bundle ceramic pillars together and combine them with section plates and partition plates to establish helium passageways as shown in FIG. 6 . (v) Attach the ceramic heat exchanging section to the assembled section plates and partition plates as shown in FIG. 7 . (vi) Attach ceramic flow rate regulating plates to the top and bottom of the fabricated heat exchanging section as shown in FIG. 8 ; subsequently attach reinforcing rings to the fabricated heat exchanging section as shown in FIG. 9 . (vii) Tighten the heat exchanging section by means of tie rods as shown in FIG. 10 . (viii) Install inner tubes as shown in FIG. 11 . (ix) In a separate step, assemble a pressure vessel for accommodating the heat exchanging section as shown in FIG. 12 . (x) Install the heat exchanging section within the pressure vessel as shown in FIG. 13 . (xi) Further, fit earthquake-resistant structures between the pressure vessel and the heat exchanging section as shown in FIG. 14 . (xii) Attach a top reflector and helium inlet bellows as shown in FIG. 15 . (xiii) In the last step, fit a top cover and a mechanical seal on the pressure vessel as shown in FIGS. 16 and 17 , respectively.
(B) Concentrated Sulfuric Acid Corrosion Test
The various ceramics and refractory alloys shown in Table 2 were filled into glass ampules together with concentrated sulfuric acid and subjected to a high-temperature, high-pressure corrosion test in an autoclave (see FIG. 18 ) under high-temperature (460° C.) high-pressure (2 MPa) conditions for 100 and 1000 hours. Test results are shown in Tables 3 and 4 and in FIG. 19 . The results for the 1000-h test are summarized in Table 5. Silicon carbide and silicon nitride were found to have satisfactory corrosion resistance.
TABLE 2
Test Sections for High-Pressure Boiling H 2 SO 4 Corrosion Test (×100 h and 1000 h)
Description
Ampule No.
Designation
Symbol
Classification
Remarks
100 h test
1
SiC
SiC-1
ceramic
atmospheric pressure sintering of 97 wt %
SiC, 1 wt % B and 2 wt % C
2
Si—SiC
Si—SiC—N-1
atmospheric pressure sintering of 80 wt %
SiC and 20 wt % Si (as silicon impregnated)
3
Si 3 N 4
Si 3 N 4 -1
atmospheric pressure sintering of 1 wt %
SrO, 4 wt % MgO and 5 wt % CeO 2
4
Sx
SX-2
H 2 SO 4 resistant steel
preliminarily oxidized at 800° C. × 90 h
5
FeSi
FS-1
high-Si ferrous alloy
14.8 Si—Fe
6
FS-2
19.7 Si—Fe
1000 h test
1
SX
SX-2/half
H 2 SO 4 resistant steel
oxidized with the atmosphere at 800° C. ×
90 h in half size
2
SX-2/small
oxidized with the atmosphere at 800° C. ×
90 h in small size
3
SX
SX-4/RT-1
H 2 SO 4 resistant steel
oxidized with nitric acid in small size
SX-4/70.1
oxidized with nitric acid in small size
4
SiC
SiC
ceramic
5
Si—SiC
Si—SiC—N-3
Si-impregnated silicon
carbide ceramic
6
Si 3 N 4
Si 3 N 4
ceramic
7
FeSi
FS-2/untreated
high-Si ferrous alloy
19.7 Si—Fe
FS-2/stress
19.7 Si—Fe, vacuum annealed at 1100° C. ×
relieved
100 h
TABLE 3
Results of Size Measurements in High-Pressure Boiling H 2 SO 4 Corrosion Test (×100 h)
Length (mm)
Width (mm)
Thickness (mm)
Ampule
Before
After
Change
Before
After
Change
Before
After
Change
No.
Designation
Symbol
test
test
(%)
test
test
(%)
test
test
(%)
1
SX-2
SX-2/half
26.824
26.71
−0.42%
3.949
3.944
−0.13%
1.516
1.358
−10.42%
2
SX-2/small
1.798
1.789
−0.50%
3.988
4.1
2.81%
1.545
1.589
2.85%
3
SX-4
SX-4/RT-1
15.493
15.453
−0.26%
3.943
3.878
−1.65%
1.635
1.624
−0.67%
SX-4/70.1
15.071
15.063
−0.05%
3.937
3.903
−0.86%
1.627
1.744
7.19%
4
SiC
SiC
39.727
39.71
−0.04%
4.035
4.034
−0.02%
2.993
2.991
−0.07%
5
Si—SiC
Si—SiC
40.029
40.04
0.03%
4.061
4.06
−0.02%
3.077
3.080
0.10%
6
Si 3 N 4
Si 3 N 4
39.826
39.8
−0.07%
4.065
4.068
0.07%
3.013
3.021
0.27%
7
FeSi
FS-2/untreated
19.083
19.101
0.09%
3.638
3.7
1.70%
3.595
3.638
1.20%
FS-2/stress
19.585
20.055
2.40%
5.700
3.705
−35.00%
5.557
3.578
−35.61%
relieved
TABLE 4
Results of Weight Measurements and Corrosion Rate
in High-Pressure Boiling H 2 SO 4 Corrosion Test (×100 h)
Weight (g)
Corrosion
Ampule
Before
After
Weight change
Area
rate
No.
Designation
Symbol
test
test
(%)
(mg)
(cm 2 )
(g/m 2 h)
Remarks
1
SX-2
SX-2/half
1.2162
0.9816
19.29%
−234.6
0.03052
0.961
Ampule broke in 800 h
2
SX-2/small
0.0772
0.0656
15.03%
−11.6
0.00322
0.360
3
SX-4
SX-4/RT-1
0.7570
0.6738
10.99%
−83.2
0.01857
1.244
Ampule broke in 360 h
SX-4/70.1
0.7967
0.7198
9.65%
−76.9
0.01805
1.183
Ampule broke in 360 h
4
SiC
SiC
1.4476
1.4487
−0.08%
1.1
0.05826
−0.002
5
Si—SiC
Si—SiC
1.4823
1.4856
−0.22%
3.3
0.05964
−0.006
6
Si 3 N 4
Si 3 N 4
1.5611
1.5653
−0.27%
4.2
0.05883
−0.007
7
FeSi
FS-2/untreated
1.6720
1.6330
2.33%
−39.0
0.03022
0.129
FS-2/stress
1.7425
1.7097
1.88%
−32.8
0.05043
0.065
relieved
TABLE 5
Summary of 1000 h Test
Cross section
Dimensional
Corrosion
observed at
Overall
Designation
Symbol
change
rate
Appearance
magnification
Others
rating
SX-2
SX-2/half
X
X
⊚
⊚
—
X
SX-2/small
◯
Δ
⊚
⊚
—
Δ
SX-4
SX-4/RT-1
Δ
X
⊚
⊚
—
X
SX-4/70.1
Δ
X
⊚
⊚
—
X
SiC
SiC
⊚
⊚
⊚
⊚
◯
◯
Si—SiC
Si—SiC
⊚
⊚
⊚
⊚
◯
◯
Si 3 N 4
Si 3 N 4
⊚
⊚
⊚
⊚
◯
◯
FeSi
FS-2/untreated
⊚
Δ
X
X
—
X
FS-2/stress relieved
X
Δ
X
X
—
X | Ceramic materials that are highly resistant to strong acids such as concentrated sulfuric acid and halides such as hydrogen iodide are employed to make block elements through which a large number of circular ingress channels extend in perpendicular directions and which are joined and piled in the heat exchanging medium section to provide a compact heat exchanger that excels not only in corrosion resistance but also in high-temperature strength. | 5 |
BACKGROUND OF THE INVENTION
[0001] Previous methods and devices for recording and processing audio signals (for example speech and/or sound signals) in an environment filled with acoustic noise are based either on the use of a first-order directional microphone (gradient microphones) or on a microphone array having two or more individual microphones (for example ball microphones). In the latter case, additional digital filters are used to match the frequency responses of the microphones.
[0002] Both directional microphones and microphone arrays are covered by the generic term free-field microphones, whose directivity allows the useful sound and the acoustic noise to be separated, and whose output signals are added using the “delay and sum principle”.
[0003] Microphone arrays are arrangements of a number of microphones positioned physically separately, whose signals are processed such that the sensitivity of the overall arrangement is directional. The directivity results from the propagation time differences (phase relationships) with which a sound signal arrives at the various microphones in the array. Examples of this are so-called gradient microphones or microphone arrays which operate on the delay and sum beam-former principle. A problem that arises in the practical implementation of microphone arrays is the scatter, resulting from production tolerances, in the sensitivity and frequency response of the individual microphones used. The sensitivity in this case means the characteristic of a microphone to produce an electrical signal from a predetermined sound pressure level. The frequency response represents the way in which the sensitivity of the microphone varies with frequency. The tolerance band stated by the microphone manufacturers is typically between ±2 and ±4 dB. If these microphone characteristics differ within a microphone array, then this has a negative influence on the frequency response and the directional characteristic of the overall arrangement. As a rule, the frequency response has increased ripple, while the directivity is considerably reduced. In this context, Table 1 shows the reduction in the directivity index of a second-order gradient microphone (microphone array comprising two individual cardioid microphones) when the two individual microphones have different sensitivities. The directivity index in this case indicates the suppression of diffused incident sound compared to useful sound from the microphone major axis.
[0004] Until now, the sensitivity and the frequency response of the individual microphones in an array have had to be determined by acoustic measurement and have had to be matched to one another by suitable electrical amplifiers and filters. The measurement includes the stimulation of the microphone to be measured using a sound reference signal produced via a loudspeaker, and the recording of the electrical signals produced by the microphones. The gain factors and filter parameters required for matching are then calculated from the microphone signals, and set as appropriate.
[0005] The acoustic measurement of the microphone parameters involves considerable technical complexity and results in corresponding costs for the production of microphone arrays. Furthermore, the trimming process is carried out during the production of the microphone array, so that it is applicable only to this one operating situation. Other operating situations, for example different supply voltages or aging effects of the microphones, are ignored.
[0006] A gradient microphone system is known from U.S. Pat. No. 5,463,694, which is based on the idea that microphones essentially have the same frequency response and the same sensitivity. The term “sensitivity” means the characteristic of a microphone to produce a predetermined electrical signal from a predetermined sound pressure level.
SUMMARY OF THE INVENTION
[0007] An advantage of the present invention is to record and to process audio signals with a good useful-signal to noise-signal ratio in acoustic noise conditions and with a good ratio between the direct sound and the reflected sound in an environment which in particular has no reverberation.
[0008] According to the invention, there is processing of electrical signals produced by conversion of audio signals recorded by a predetermined microphone arrangement in such a manner that, if the sound pressure levels at the microphones in the microphone arrangement are the same, electrical signals which are produced by these microphones but are of different intensity—different sensitivities of the microphones—are automatically matched, that is, without any manual matching procedures needing to be carried out individually and separately.
[0009] The invention, in this case, pertains to combining the characteristics of an array of microphones with those of a method for matching the sensitivity of microphones.
[0010] Advantages of this procedure involve simple implementation in conjunction with the (optimum) result achieved in the process and, a good relationship between the complexity of the microphone arrangement (arrays) and the result.
[0011] The result which can be achieved using the present invention is considerably better than the result which can be achieved by using U.S. Pat. No. 5,463,694. This is shown in the following table:
[0012] The table shows the relationship between the “difference between the sensitivity of the microphones (delta)” and the “directivity index”
Delta (dB) Directivity index (dB) 0 8.7 1 8.4 2 8.1 3 7.8 4 7.5 5 7.2 6 6.9
[0013] Summary: The greater the difference between the sensitivity of the microphones, the poorer is the directivity index.
[0014] The method and the device of the invention allow an optimum directivity index to be achieved for the microphone arrangement for any environment filled with acoustic noise, since it always automatically matches the sensitivity of the microphones.
[0015] One parameter for assessing a directional microphone is the directivity index. The directivity index means the extent to which diffuse (omnidirectional) incident sound is suppressed in comparison to useful sound from the major axis. In this case, the directivity index is a logarithmic variable, and is therefore expressed in decibels.
[0016] The present invention preferably comprises an array of microphones and filters in order to match the sensitivity of the microphones and to achieve the desired array frequency response.
[0017] In comparison to known microphone arrays, which require complicated digital filters in order to match the frequency responses of the microphones, the inventive method and device require only the sensitivity to be matched. Furthermore, this can be achieved either by a simple digital filter, or by an analog circuit.
[0018] With the inventive array, in which two simple directional microphones are used, directivity indexes are achieved which cannot be achieved with a single directional microphone. An array of ball microphones can achieve this result, but only by using more than two microphones to form the array. Furthermore, preferably, a filter is required for each microphone in order to match the frequency responses of the various microphones.
[0019] In order to match the sensitivity of the microphones, the microphones should be stimulated using a sound preferably source which is arranged at right angles to the axis of the microphones, in order to calculate the sensitivity correction. However, this is not always feasible in practice.
[0020] Alternatively, it is also possible to match the sensitivity independently of the position of the sound source. For example, when the sound source has only low-frequency components whose wavelengths are much longer than the distance between the microphones. In a microphone arrangement having two microphones, the wavelength should, for example, be greater than twice the distance between the microphones, while the wavelength for a microphone arrangement having more than two microphones should be greater than the sum of the distances between the individual microphones.
[0021] Furthermore, the microphones are preferably positioned in pairs such that their major axes lie on a common axis. However, deviations from this are also possible with regard to a tilt or adjustment angle, which can vary, for example, in the range between 0° and 40°, and with respect to an offset distance which, for example, is less than or equal to the distance between the microphones. In all these different situations, there is preferably one reference microphone with a reference major axis with respect to which each of the other microphones in the microphone arrangement is arranged at an adjustment angle to the major axis and at an offset distance from it.
[0022] The signals from the microphones are processed, for example, by a block in order to match the sensitivity of the microphones. The sum and the difference are then formed from the two signals, and combined to form a linear combination in order to obtain a signal with a higher-order directional characteristic than that of the two microphones in the array.
[0023] The signal is then processed using a filter in order to achieve the desired array frequency response and sensitivity.
[0024] Furthermore, it is advantageous if the microphone arrangement is a second-order gradient microphone (quadrupole microphone) arranged on an “acoustic boundary surface since this improves the ratio between the signal and the self-noise. In acoustics, an “acoustic boundary surface” is a hard surface, for example a table in a room, a window pane or the roof in a car etc. In this case, the ratio between the useful signal and the environmental noise is furthermore increased when sound is recorded in situations with high environmental noise, for example in vehicles or in public spaces. The subjective comprehensibility of recorded speech is thus improved in an environment with reverberation, for example in spaces with highly reflective walls (car, telephone cubicle, church, etc.).
[0025] The quadrupole microphone consists of a combination of two first-order gradient microphones with a cardioid characteristic, whose output signals are subtracted from one another. This measure increases the directivity index from 4.8 to 10 dB. The directivity index in this case indicates the gain with which the useful signal incident on the microphone major axis is amplified in comparison to the diffuse incident noise signal. Suitable arrangement of the individual microphones in the quadrupole microphone on a boundary surface improves the useful signal sensitivity of the microphone by a further 6 dB, and significantly improves the useful signal to self-noise ratio of higher-order gradient microphones, which is in principle low in the lower frequency range.
[0026] A significant advantage of the present invention is that the complexity involved in achieving improved useful signals is small in comparison to that of previous solutions. At the same time, the external dimensions of the boundary surface quadrupole microphone are less than with known arrangements of comparable directivity. The proposed arrangement avoids interference between the incident direct sound and the sound which is reflected by the boundary surface and can interfere with the directivity of a microphone close to a boundary surface.
[0027] The boundary-surface construction of the gradient microphone raises the microphone useful signal incident on the major axis by 6 dB with respect to the microphone self-noise.
[0028] Higher-order gradient microphones constructed with a boundary surface can be used sensibly wherever high-quality recording of acoustic signals is required in a noisy environment. In addition to high noise signal suppression, the high directivity of the microphone also achieves considerable suppression of reverberation in rooms, so that this considerably improves the capability to understand speech, even in quiet rooms. Examples for the use of the proposed invention include hands-free devices for telephones and automatic voice recognition systems, as well as conference microphones.
[0029] Additional features and advantages of the present invention are described in, and will be apparent from, the Detailed Description of the Preferred Embodiments and the Drawings.
BRIEF DESCRIPTION OF THE FIGURES
[0030] FIG. 1 is a schematic diagram of a microphone array according to the present invention.
[0031] FIG. 2 is a schematic diagram of another microphone array according to the present invention.
[0032] FIG. 3 is a schematic diagram of an automatic microphone sensitivity trimming for n microphones in an array.
[0033] FIG. 4 is a schematic diagram of an automatic microphone sensitivity trimming for two microphones, with the signal levels of both microphones being regulated.
[0034] FIG. 5 is a schematic diagram showing a trimming process according to the present invention.
[0035] FIG. 6 is a schematic diagram of a trimming apparatus according to the present invention.
[0036] FIG. 7 is a circuit diagram for sensitivity and frequency response control of microphones according to the invention.
[0037] FIG. 8 is another circuit diagram for sensitivity and frequency response control of microphones according to the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0038] The way in which the sensitivity trimming is carried out is shown in FIGS. 1 and 2 . If the two microphones have approximately the same frequency response, sensitivity trimming in a restricted frequency range is sufficient to achieve the desired directivity over the entire transmission band. In practical situations, the condition of “equal frequency response” is satisfied to a good approximation.
[0039] The filter illustrated in FIG. 2 may advantageously be in the form of a low-pass filter with a cut-off frequency of, for example, 100 Hz.
[0040] The possible applications for a second-order gradient microphone include all situations where good speech transmission is required in noisy surroundings. For example, this may be a microphone for a hands-free system in a car, or the microphone for a voice recognition system operating in the hands-free mode.
[0041] Automatic Trimming of Microphone Sensitivity
[0042] The present invention can address the problem of microphone sensitivity trimming by automatic trimming of the microphone signal levels during operation of the microphones in an array. In this case, the existing environmental noise level or useful signal level is sufficient. The microphone signal levels and amplitudes recorded by the microphones are measured and are matched to one another independently of their respective phases. In this case, it must be assumed that the sound pressure levels arriving at the microphones are virtually the same, or that the discrepancies are considerably less than the microphone sensitivity tolerance. This condition is satisfied when the distance between the sound source which dominates the sound level and the microphone array is considerably greater than the distance between the microphones to be trimmed, and no pronounced space modes occur. The signal levels can be measured by any type of envelope curve measurement or by real root-mean-square value measurement. The time constant for this measurement must in this case be longer than the maximum signal propagation time between the microphones to be trimmed. The sensitivity trimming can be carried out by amplification or attenuation in the opposite sense to the discrepancy between the signal levels.
[0043] FIG. 3 shows the block diagram of the automatic microphone sensitivity trimming for n microphones in an array. Microphone 1 is in this case the reference microphone, to whose microphone signal level the levels of the other microphones 2 to n are matched. The circuit diagram is composed of blocks whose gain or attenuation is controllable and units for signal level measurement. The measured signal levels are used to produce difference or error signals e n , which are used as the control variable for the variable amplifiers or attenuators. Overall, there are n−1 regulators, whose reference variable is the signal level of the reference microphone. In order to satisfy the distance condition mentioned in the previous paragraph, adjacent microphones can also be trimmed in pairs (not shown in FIG. 3 ).
[0044] FIG. 4 shows the block diagram of the automatic microphone sensitivity trimming for two microphones, with the signal levels of both microphones being regulated. The advantage of this embodiment over an embodiment with an unregulated reference microphone as shown in FIG. 3 is that there is less variance between the output levels, since it is possible to use the mean sensitivity of the microphones for regulation.
[0045] The automatic microphone trimming proposed here can be implemented easily in terms of circuitry and requires no further trimming steps, such as complex acoustic trimming. This results in clear cost advantages even for small microphone array quantities. Furthermore, the method allows continuous trimming, so that it is also possible to take account of changes in the microphone sensitivity occurring over time.
[0046] Automatic Trimming of the Microphone Frequency Response
[0047] Automatic microphone frequency response trimming is a generalization of microphone sensitivity trimming. For frequency trimming, it must be assumed that the spectral distribution of the sound arriving at the microphones in the frequency ranges in which compensation is to be carried out is similar, and that any discrepancies are well below the microphone frequency response tolerance bands. This condition is once again satisfied for a sound source located well away in comparison to the distance between the microphones (see the distance condition, further above).
[0048] The trimming process is carried out in sub-bands of the microphone transmission frequency band, and can be carried out by equalization using either appropriate analog or digital filters. In the most obvious case, this is a filter structure comprising bandpass filters connected in parallel (as shown in FIG. 5 ) or in series, and whose gains can be controlled independently of one another. The sum frequency response of the filters for the unregulated reference microphone ( FIG. 5 fil x1 , fil x2 . . . fil xn ) is flat in the desired transmission frequency band. The frequency response of the comparison microphone is compared to that of the reference microphone by raising or lowering (amplifying or attenuating) the filter sub-bands (fil y1 , fil y2 . . . fil yn ). The control signals g 1 , g 2 , g n required to do this are derived directly from the error signals (g 1 ˜e 1 , g 2 ˜e 2 . . . g n ˜e n ) obtained for the individual frequency bands. A large number of bandpass filters are usually required for precise trimming.
[0049] The complexity of the filter structure can be reduced considerably if those microphone parameters which are dominant in specific frequency bands, such as the configuration of the sound inlet opening, the front/back volume, the diaphragm flexibility and their electrical equivalent circuits are known, and discrepancies between microphones can be traced back to changes in individual parameters. The trimming process can be carried out with comparatively little complexity by means of appropriate equalization filters, which specifically counteract these discrepancies.
[0050] FIG. 6 shows the block diagram of a trimming apparatus which comprises a controllable equalization filter, weighting filters and level measurement units. The equalization filter is once again actuated via the difference signal e from the level measurement units, in which case both the amplitude and the phase frequency response are generally varied.
[0051] The advantages mentioned for sensitivity trimming also apply to automatic trimming of the microphone frequency response.
[0052] Simple Control of the Sensitivity of Microphones with an Integrated Amplifier, Whose Operating Point can be Adjusted by Means of External Circuitry, for Example a Field-Effect Transistor Preamplifier (Feet Preamplifier)
[0053] Virtually all the microphone capsules used currently in telecommunications and consumer applications are electorate transducers with an integrated field-effect transistor preamplifier. These preamplifiers are used to reduce the very high microphone source impedance and to amplify the microphone signal. Generally, this represents the source circuit of a field-effect transistor. The operating point of the transistor, and hence the sensitivity of the microphone as well, can be varied by varying the supply impedance and the supply voltage. The microphone frequency response can be varied, provided not just real but also complex supply impedances are acceptable.
[0054] FIGS. 7 and 8 each show a circuit for sensitivity and frequency response control of electronic microphones, which does not require any external, controllable amplifiers or attenuators. An implementation provides sensitivity and frequency response control via the microphone supply voltage U L , which, in the case of automatic sensitivity trimming or matching, can be derived directly from the difference signal between the measured sound levels or signal levels U L =(v·e n )+U 0 (v in this case denotes a gain factor and U a constant voltage parameter, for example the output voltage before sensitivity and frequency matching). The control range of the microphone sensitivity by varying the microphone supply voltage is up to 25 dB, depending on the supply impedance (see Table 2).
[0055] Alternatively, it is also possible to provide sensitivity and frequency response control in such a manner that the microphone supply impedance Z L with a control voltage U ST which, in the case of automatic sensitivity and frequency response trimming and matching, can be derived directly from the difference signal between the measured sound levels and signal levels U ST ≈((v·e n )+U 0 ′) (v in this case denotes a gain factor and U 0 ′ a constant voltage parameter, for example the output voltage before sensitivity and frequency response matching).
[0056] The supply impedance Z L can be controlled electronically by means of a controlled field-effect transistor for real values, and by means of a gyrator circuit for complex values. The control range of the microphone sensitivity via the supply impedance is up to 10 dB, depending on the microphone supply voltage (see Table 2).
[0057] One advantage of this type of sensitivity and frequency response control is that the circuit complexity is minimized, as well as the costs associated with it. The control range is sufficiently high for most applications.
[0058] Accordingly, to an embodiment, the present invention provides sensitivity and frequency response trimming by the separation of amplitude and phase information from the sound arriving at the microphones, which allows automatic trimming while microphones are being operated in an array. While the phase relationship is used to form the directional characteristic of an array, the amplitude relationship is available for trimming of the microphone sensitivities and of the amplitude frequency responses. Production tolerances relating to these microphone parameters can thus be compensated for, so that the desired frequency response and the directional characteristic of the overall arrangement are obtained.
[0059] According to an embodiment, the present invention provides sensitivity control of microphones having an integrated FET preamplifier by the use of the supply voltage or of the supply resistance to vary the FET operating point, and hence the gain of the FET preamplifier.
[0060] The inventive microphone trimming can be used for all multiple microphone arrangements whose directional sensitivity is obtained by using the phase relationships between the individual microphone signals. These microphone arrangements can sensibly be used wherever high-quality recording of acoustic signals is required in a noisy environment. The directional characteristic of these arrangements in this case allows acoustic noise (environmental noise, reverberation) away from the microphone major axis to be attenuated, and adjacent sound sources (other speakers) to be separated. By avoiding complex acoustic trimming, automatic microphone trimming allows considerable cost savings during production, and thus also makes it possible to use microphone arrays in consumer applications, for example in hands-free devices for communications terminals or for equipment voice control. Further applications of microphone arrays in which the invention can sensibly be used are conference microphones.
[0061] The trimming invention has been implemented in a simple electronic circuit and has been tested using a second-order gradient microphone. Gradient microphones are formed by interconnecting two cardioid microphones, whose sensitivity is automatically trimmed by means of the circuit. The sensitivity control for the microphone to be trimmed is carried out using the principles of the present invention. Microphone trimming operates even at low environmental noise levels (room volume) and is independent of the sound incidence direction.
[0062] The sensitivity control for microphones with a built-in FET preamplifier can also advantageously be used for automatic control of microphone signal levels. These circuits are generally referred to as automatic gain control circuits. Practical applications for such circuits include all consumer equipment having a microphone recording channel (cassette recorders, dictation systems, hands-free telephones, etc.).
[0063] Although the present invention has been described with reference to specific embodiments, those of skill in the art will recognize that changes may be made thereto without departing from the spirit and scope of the invention as set forth in the hereafter appended claims. | In order to record and to process audio signals with a good useful-signal to noise-signal ratio in acoustic noise conditions and with a good ratio between the direct sound and the reflected sound in an environment which in particular has no reverberation electrical signals produced by conversion of audio signals recorded by a predetermined microphone arrangement are processed in such a manner that, if the sound pressure levels at the microphones in the microphone arrangement are the same, electrical signals which are produced by these microphones but are of different intensity—different sensitivities of the microphones—are automatically matched, without any manual matching procedures needed to be carried out individually and separately. A microphone arrangement is based on combining the characteristics of an array of microphones with those of a method for matching the sensitivity of microphones. | 7 |
BACKGROUND OF THE INVENTION
Vaccination or immunization is the most efficient measure to control infectious diseases in humans and in domestic animals. Also, in cancer immunotherapy, it is desired to stimulate an immune response against the tumor cells. Another application of immunization is in birth control. Sources of vaccine antigens include live attenuated or inactivated pathogens, and subunits, rDNA derived polypeptides, recombinant viruses, synthesized polypeptides and anti-idiotypes.
However, there are many diseases including AIDS and tropical diseases for which vaccines are not yet available or are not satisfactory. Similarly, immunotherapy is not a reliable method to treat tumors, in general.
Immunity to disease is due to the actions of specialized cells, especially the B and T lymphocytes. A basic description of the cellular basis of immunity may be found in Molecular Biology of the Cell (B. Alberts et al., Garland Publishing, Inc., New York, 1983). While the cellular basis of the immune system is understood in much greater detail than described in this reference, the basic principles can be clarified by its teachings, which state that the immune response is due primarily to the actions of specific cells, the B and T lymphocytes, which themselves consists of many subtypes. Virtually all lymphocyte responses are due to complex interactions among a variety of these and other cell types. In particular, the proliferation and differentiation of B and T cell effector cells and memory cells which underlies the desired objectives of immunization results from the interaction in the presence of the antigen between the class of T cells known as "Helper T cells" (Th) and either B lymphocytes or cytotoxic T cells. Also, the T cell recognition of antigens requires interaction with "antigen presenting cells" (APC) which incorporate antigen fragments into Type II MCH on the APC cell surfaces; APC cells include the B lymphocytes, macrophages, and the mast cells.
An addition, there are medical situations in which the suppression of immune reactions is desired; e.g., treatment of autoimmune diseases and allergies and in the transplantation of organs. In cellular terms, tolerance to antigen involves a class of T lymphocytes known as "Suppressor T cells" (Ts). The induction of immune tolerance is also within the scope of the instant invention.
This interaction between Th cells and other B or T cells is mediated by the production of hormonal factors known as lymphokines by Th cells which stimulate the growth and differentiation of effector and memory cells. The transmission of lymphokines from Th to target B or T cells is mediated by diffusion and takes place in the immediate vicinity of the Th-antibody interaction; sufficiently high concentrations of lymphokines to stimulate cell responses do not exist systemically. The interaction may also occur by synapse-like contacts between the cells. Monokines produced by the antigen presenting macrophages are also involved in the activation of T cells, representing another form immune cell communication by means of a soluble protein.
Generally, when killed organisms or their antigens are used for the vaccination or immunization the antigen is injected with a syringe into an appropriate body site. Thereafter, the T and B lymphocytes capable of recognizing the antigen may be attracted to the site of injection and interact with each other and with presenting cells such as mast cells there to produce the immune response. Alternatively, antigen can be transported in the lymphatic circulation to lymph nodes which are specialized organs which facilitate these cell-cell interactions with antigen.
Several problems occur in immunization, however. (1) the response is not always predictable: either immune stimulation or tolerance can be induced; (2) the response to a given antigen preparation in a given host species (e.g. human being, domestic animal, or laboratory animal) can vary greatly from individual to individual; (3) some antigens produce no response or weak responses in comparison to other antigens (4) the response may In particular, many highly purified bacterial and viral components are weak antigens. There is a particular need to overcome this problem since advances in molecular biology can now make available small and highly purified antigenic components of pathogenic organisms.
Two methods are used to partially overcome the above described problems: carriers and adjuvants. These methods are not always clearly distinguished, and the instant invention contains elements of both of these. A carrier is generally a macromolecule to which a hapten (an antigenic determinant which binds to lymphocyte receptor but cannot induce an immune response) is bound; carriers include tetanus toxoid, diphtheria toxoid and purified protein derivatives. An adjuvant enhances an immune response; examples are Freund's adjuvant (used in animal experimentation), and alum (sometimes used in human vaccines). Other adjuvants include SAF-1 (Synthex), Nor-MDP (Ciba-Geigy), Sqaulene, and Zymozan and "iscoms" (immune-stimulating complex). Additional information on adjuvants included within the scope of this invention are found in Adam, Synthetic Adjuvants, Wiley & Sons, 1985.
Novel concepts in adjuvants or improved antibody presentation include the use of lymphokines as adjuvants, the coupling of antigens with antibodies against the surface molecules of antigen presenting cells (e.g. Type II major histocompatibility complex (MHC); B cell surface antibody). Another recent advance in antigen presentation is the use of biodegradable microspheres made of polylactic/polyglycolic acid copolymers to prolong antibody release. These approaches are disclosed in the "Report of a Meeting on Basic Vaccinology" held by the WHO in Geneva, Dec. 8-11, 1987. Similar approaches are disclosed in U.S. Pat. Nos. 4,225,581 and 4,269,821.
It has been suggested that porous collagen-glycosaminoglycan (collagen-GAG) can be used as a microsphere carrier for the controlled release of antigen or attenuated microorganisms. The porous collagen-GAG can be used to immobilize microorganisms in the pores by physical entrapment or chemical crosslinking; other antigens can be chemically crosslinked to the porous matrix. These microspheres can thus be used as biodegradable vehicles for the antigens. A possible disadvantage of collagen as a material to form microspheres in comparison with certain synthetic materials such as polylactic acid/polyglycolic acid copolymers is the endogenous antigenicity of collagen. Such macroporous microspheres may range from 1 μm to about 1000 μm. A preferred particle size for such a microsphere would be less than about 50 μm to enable the adjuvant to be delivered by injection. For introduction of microorganisms into a preformed microsphere, a desired pore size would be in the micron range; for immobilization of molecular antigens, submicron pore sizes would be appropriate.
A similar controlled release experimental vaccine for rabbits has made by co-polymerizing virus particle and virus subunits into rabbit serum albumin beads (Martin, M.E. et al., Vaccine, 1988 February 6(1). p 33-8).
For induction of tolerance, experiments are underway in which microspheres of porous collagen-chondroitin-6-sulfate (C6S) (obtained from Biomat Corporation) of about 500 μm diameter and with mean pore sized of about 20 m near the surface and of about 50-80 μm in the interior are seeded with bone marrow cells from a donor animal. These microspheres are implanted into a host animal, which is also treated with an antilymphocyte serum. This process is intended to induce tolerance in the host so that an organ can also be transplanted from that donor to that host without rejection by the host animal. This procedure can be distinguished from the application of the instant invention in the induction of tolerance as its sole application to organ transplantations and in its specific use of bone marrow cells as well as antilymphocyte serum. Also, the antigens are not crosslinked to the collagen-GAG matrix.
Biodegradable microspheres can help in the presentation of antigen, for example by prolonging delivery, but they do not enhance or direct the cellular interactions underlying immune response, which is an objective of this invention.
OBJECTIVES OF THE INVENTION
One object of the instant invention is to bring about the efficient interaction of lymphocyte cell types resulting in a stronger, longer lasting, or more consistent immune response.
A further object of the invention is to target the interaction with antigen to specific classes of cells so as to preferentially stimulate either humoral antibody response, cytotoxic T cell response, or immune tolerance.
Another object of the invention is to induce a therapeutic response to a weak antigen by providing an improved carrier or adjuvant for the antigen.
Another object of the invention is to prolong the contact of antibody and lymphocytes by providing a slow release mechanism for the antigen.
Another object is to provide an improved adjuvant by incorporating natural lymphokines in a controlled release form together with the carrier and antigen.
Another object is to enhance the cellular immune attack on pathogens such as viruses by trapping pathogens or pathogeninfected cells, thus controlling the presentation of the pathogens to the cellular immune system or enhancing the delivery of chemotherapeutic agents. These and other objectives will be apparant from the description below.
SUMMARY
A macroporous microsphere is disclosed comprising a particle mode of a polymer, having a size of 1 to 1000 microns, with pores having a mean pore diameter of 0.1 to 100 microns. The microsphere pores may be adapted to bind to a hapten.
DESCRIPTION OF THE INVENTION
The basic invention includes a macroporous microsphere or other particulate shape having a high internal surface area. Antigens are physically entrapped in or chemically crosslinked to the interior. The microsphere can be made from natural biopolymers, such as collagens or glycosaminoglycans (GAG) or from synthetic polymers such as polylactic acid polyglycolic acid copolymer. Ideally, the particle is sufficiently small that it can be injected with a syringe, e.g., 1 to 100 μm preferably below about 50 μm diameter. The open pore structure has a mean pore size such that various classes of lymphocytes can enter and interact both with antigen and with each other. (Since small lymphocytes have diameters of about 6 μm, activated T cells have diameters of about 9 μm, and activated B cells have diameters of about 8-12 μm, mean pore sizes of about 5-15 μm would be optimal, although acceptable pore sizes could range from about 3-100 μm.)
Microspheres fitting these specifications can be formed from the collagen-GAG copolymers developed by Yannas and described in U.S. Pat. Nos. 4,060,081, 4,280,954, 4,350,629, 4,418,691, 4,448,718, 4,458,678, 4,522,753, 4,405,266. Other similar materials which may be suitable are described in U.S. Pat. Nos. 4,614,794 and 4,378,017.
Other materials which could be used to form microspheres include carbohydrate polymers such as those under development by Alpha-Beta Technology (Worcester, Mass.) and surface-active synthetic copolymers such as those under development by CytRx (Norcross, Ga.). Any polymeric adjuvant material may be used to construct the porous matrix, or any of these agents may be crosslinked to it; polymeric adjuvants include glucans, polysaccharides, lipoproteins, poly (CTTH-iminocarbonate) [Kohn, J. et al, J. Immunol. methods, 95:31-8, 1986], ethylene-vinyl acetate copolymer [Niemi, S. M., et al, Lab. Anim. Sci. 35:609-12, 1985], etc. Preferably, all materials used herein should be biodegradable.
Larger particles, such as particles usable as porous microcarriers in animal cell culture with particle sizes of 300-1000 m are used also, but are not as easily deliverable by syringe. Other forms of macroporous materials such as sheets, are within the scope of this invention, but are also not easily injectable by syringe.
Antigens which can be crosslinked to such a particle include whole inactivated pathogens, and subunit thereof, rDNA derived polypeptides, recombinant viruses, synthesized polypeptides and anti-idiotypes. Whole microorganisms or animal cells can be also physically entrapped in small pores and cul-de-sacs of the matrix without necessarily being crosslinked to it. Procedures to entrap whole cells in porous matrices are described in U.S. Pat. Nos. 4,418,691, 4,458,678, and 4,505,266 to Yannas, et al.
Suitable chemical crosslinking procedures for immobilization of the antigens include bifunctional aldehydes such as glutaraldehyde, carbodiimides, and other "linkers" or crosslinking agents well known in the art of the immobilization of antibodies, other proteins, or carbohydrates. If the microsphere is made primarily of collagen, and it is desirable to avoid altering the antigenic properties of the collagen, the crosslinking method of Siegel (U.S. Pat. No. 4,544,638) may be used. In the preferred mode of using the invention, an inert insoluble microsphere is preformed and the antigen is contacted with it and crosslinked to it later, followed by washing out the unreacted components, and formulating the microspheres into an injectable form. A crosslinking method which contains separate steps of activation of the matrix, for example with cyanogen bromide, followed by reaction of the antigen with the activated matrix may be preferred in this case since it offers less risk of altering the antigenic properties of the antigen.
A particle which maintains the lymphocytes in the interior in contact with the antigen has basic steric or geometric advantages over a particle which releases antigen to interact with lymphocytes exterior to it:
1. By immobilizing antigens on the large surface area, locally high antigen concentrations can be maintained in direct proximity to or direct contact with the lymphocytes.
2. Given that the clonal selection theory predicts that a fixed number of lymphocytes reactive to a given antibody are available to be recruited to the vicinity of the antigen injection, internalizing them in the porous particle creates a higher concentration of these cells, thus increasing the probability of forming the cell-cell contacts important for immune stimulation.
3. Lymphokine and monokine concentrations are determined by a balance between production by the cells and diffusion from their vicinity. A higher concentration of Th cells will increase the concentration of lymphokines in the vicinity of the receptor cells because the higher cell concentration and smaller surface area of the region in which the interacting cells are located.
4. The high surface area matrix also can serve as a carrier to enhance the response to the bound antigen or hapten.
5. It may be possible to control the porosity of the material to physically exclude certain classes of lymphocytes.
Although synthetic polymers or natural biopolymers such as collagen can be used to form the matrix of the microsphere, collagen-GAG has certain advantages:
1. Collagen and GAG are natural polymers which have low toxicity and are naturally biodegradable. The degradation rate can be controlled by variation of GAG concentration and degree of crosslinking. Ideally, the degradation rate is designed to allow sufficient time for desired immune responses to occur, but permit rapid degradation thereafter.
2. Collagen-GAG has much lower immunogenicity in comparison with native collagen. In artificial skin wound dressings, the dressing is accepted by the host even though bovine collagen is used. Immunogenicity may be further reduced by use of collagen of human origin (e.g. Residue B of Play et al, U.S. Pat. No. 4,511,653) or the use of a teliopeptide collagen in which the more immunogenic teliopeptide regions of the collagen molecules are removed.
3. Collagen-GAG is highly compatible with blood in comparison to native collagen.
4. The GAG component of crosslinked collagen-GAG materials can be varied to modify the biological properties of the complex.
Other polyanionic polysaccharides, such dextran sulfate and those of marine plant origin (carrageenans, alginates), can be substituted for GAG in the production of porous matrices; for example, U.S. Pat. No. 4,614,794 describes such a modification. Since in in vitro experiments, such anionic polysaccharides exhibit some of the biological properties of the GAGs (Fujita et al, Hepatoloqy, Vol. 7, p 1S-9S, 1987), matrices formed from all of these materials are considered within the scope of this invention.
U.S. Pat. No. 4,378,017 describes composite materials of collagen and de-N-acetylated chitin. The use of such materials to form the microspheres of this invention are also within the scope of this invention. Crosslinked gels of hyaluronic acid (U.S. Pat. No. 4,636,524), other GAGs, or polyanionic polysaccharides may also be suitable materials if formed into porous microspheres.
The basic invention also includes certain elaborations to enhance or control the immune response or to increase the ease of its administration.
1. In addition to antigen, small particles of a controlled release formulation of lymphokines and/or monokines can be incorporated into the matrix.
2. Antibodies against MHC II or B cell surface antibodies can be crosslinked to the matrix in addition to antigen.
3. The matrix can be preseeded with host lymphocytes or with presenting cells, such as mast cells.
4. To improve the ease of injecting the microspheres through a syringe, the particles can be prepared in a compressed form, and allowed to expand after injection. A specific prototype method of achieving such a compression is presented in Example 2, below.
5. The microspheres can be injected together with other adjuvants, such as alum, or iscoms.
6. Inflammatory or immunostimulatory agents such as histamine or prostaglandins can be incorporated, preferably as a controlled release formulation; diffusion of these agents into surrounding tissues can help recruit lymphocytes to the microsphere.
7. Presenting the antigen in the interior of microspheres offers unique options in constructing polyvalent vaccines; Two or more antigens can be combined into the same particle to enhance mutual recognition of the antigens, or two or more antigens can be presented on separate particles to stimulate independent cellular responses to these antigens.
8. Other biodegradable fibers can be incorporated into the matrix to enhance mechanical strength.
9 Destruction of lymphocytes responding to the antigen-containing microsphere can be accomplished by the administration of cytotoxic agents, such as antilymphocyte serum or anti-metabolites such as cyclophosphamide. Controlled release formulations of these cytotoxic agents can be incorporated into the microspheres. Either immune tolerance (by destruction of responding B cells or cytotoxic T cells) or the reversal of tolerance (by destruction of suppressor T cells) could be accomplished in this way. The targeting of the response to cytotoxic or suppressor cells might be accomplished by the method described below.
In addition to these elaborations, an important objective of the instant invention is the ability to design the microsphere so as to more accurately target the immune response. This possibility arises from the role of extracellular matrix (ECM) molecules in the growth and differentiation of cells. The immune response may be regarded as a specific and specialized case of cell differentiation. Co-pending U.S. patent application No. 07/149,651 describes the formation of materials from components of the ECM, including collagen-GAG materials and "biomatrix" (an extract of the ECM) designed to support the differentiation of specific cells or to maintain their differentiation in vitro; this application is incorporated herein by reference.
To direct specific lymphocyte cell types to the matrix, specific collagen and GAG components attractive to these cells can be incorporated into the matrix. Different regions of the lymph node are attractive to the T and B lymphocytes; presumably this attraction is mediated by differences in the chemical composition of the extracellular matrix of these regions. Although this chemistry is not yet known in detail, the lymph nodes are rich in "reticular fibers" comprised of type III collagen fibers as well as type IV collagen and heparan sulfate proteoglycans. Other evidence for the importance of ECM components to immune responses are the observations that both heparin proteoglycans and chondritin sulfate proteoglycans are associated with the mast cells and natural killer cells which are associated with inflammatory responses (Stevens, R. L., Ciba-Found-Symp. 1986, p 272-85). Additional evidence for the importance of the GAG component of the ECM in immune responses comes from observation that a chondroitin sulfate proteoglycan is associated with the immunoregulatory Ia proteins of the MHC; inhibitors that prevent the addition of the GAG apparently depress the antigen-presenting function of the MHC.
Accordingly, one embodiment of this invention is the construction of the collagen-GAG matrix from specific collagens and GAGs chosen empirically to increase the concentrations within the matrix of specific subtypes of lymphocytes, especially specific regulatory T lymphocytes. By increasing Th concentration, the immune response to antigen would be enhanced, by increasing Ts, tolerance may be enhanced. Similarly, increasing concentrations of cytotoxic T cells relative to B cells would enhance the cellmediated immunity, whereas the increase in B cells would favor humoral antibody response.
In addition to vaccine applications of porous microspheres, the treatment of AIDS or infection by its cause, the human immunodeficiency virus (HIV) by stimulation of the CD8+subset of suppressor T cells, as proposed by Levy et al (Science, Vol 234, p1563-6, 1986), is another application; such an approach would be advantageous in comparison to the isolation and in vitro replication of the CD8 subset. Either HIV antigens, T cell growth factors (preferably in controlled release form), or both could be incorporated into the microsphere to target activity of the microsphere to the desired cell subclass.
As another therapeutic use, the porous microspheres described herein can be utilized as traps for pathogens. One example is a porous particle which selectively traps virus-infected cells, for example HIV-virus infected T lymphocytes. Since HIV-virus infected cells express the gp120 antigen on their surfaces, a matrix crosslinked to gp120 antibodies, or to soluble CD4 would bind infected cells. Cytotoxic agents in immobilized or controlled release form could also be incorporated to kill the infected cells. Alternatively, antiviral agents such as azidothymidine (AZT), dextran sulfate, ddC, ddA, ddI, phosphonoformate, rifabutin, ribaviran, phosphorothionate oligodeoxynucleotides, castanospermine, alpha interferon, or ampligen could be incorporated. These agents and their utilization in AIDS therapy are described by Yarchoan et al (Scientific American, October, 1988, p 110). Other anti-AIDS drugs used in experimental therapy, such as AL721, azimexon, cyclosporin, foscarnet, HPA-23, imreg-1, inosine pranobex, D-penicillamine, and suramin, could also be used; these agents are described in Chemical & Enqineerinq News, December 8, 1986, p 7-14. If a collagen matrix is used, dextran sulfate can be incorporated in place of or in addition to GAG, using fabrication and crosslinking methods. Diffusible chemoattractive agents in controlled release form might also be included to enhance the recruitment of the infected T cells. By use of pore sizes too small for fibroblasts to easily enter, the selectivity of the matrix for lymphocytes is enhanced.
Other possible applications of porous cytotoxic traps designed on these principles would include treatments for leukemias and autoimmune disease. For autoimmune disease treatment, either an anti-idiotype antibody or the cellular molecule being attacked by the autoimmune disease (either extracted from tissue or made by recombinant DNA technology) is crosslinked to the matrix. Leukemia cells may be attracted by choice of extracellular matrix components and/or by crosslinked antibodies or anti-idiotypes. Once attracted to the matrix, the cells can be either killed by cytotoxic agents or induced to differentiate by differentiation factors.
Still another application of the porous microsphere described herein is to entrap pathogenic parasites, bacteria, yeast, virus, etc. by means of antibody to the pathogen crosslinked to the matrix. Affinity for the pathogen is accomplished by use of a cellular macromolecule recognized by the pathogen, for example soluble CD4 to entrap HIV virus. Such as system functions to kill the pathogen by use of cytotoxic agents or antibiotics in high local concentrations, or improves the presentation of the pathogen to the immune system. For example, as an AIDS therapy, immobilizing the virus in this way inhibits the formation of syncytia and thus attenuates the virulence of the virus. For these applications, the pore size of the matrix can be decreased to below 5 μm to prevent entry of lymphocytes and thus inhibit direct interaction of the pathogen with host cells, but allow the entry of viruses or macromolecules. To allow entry of HIV virus, with a diameter of about 0.13 μm, the mean pore size should be greater than about 0.1 μm. Optimal mean pore sizes would be between about 0.2 μm and 2 μm. In the case of entrapped HIV virus, the infection of lymphocytes during the biodegradation of the matrix may be controlled by incorporation into the matrix of some of the antiviral agents listed above. Particles with pore sizes below about 1 μm could be made with diameters smaller than about 10 μm; such particles could be injected into the blood stream, if made of blood compatible biomaterials. A collagen-GAG matrix including heparin as part or all of the GAG would have good blood compatibility.
EXAMPLES
Example 1
Bovine hide collagen from limed hides is dispersed in 900 ml of 0.05M acetic acid at 0.55 % w/v and comminuted with an IKA T50 blender for about 5 minutes until a viscous gel is formed; 100 ml of 0.4 % w/v C6S is added slowly while blending is continued. The mixture is degassed, and formed into droplets about 50 μm in diameter. The droplets are frozen at a rate such as to obtain mean pore sizes of about 10 μm, freeze dried, and dehydrothermally crosslinked by heating to 105° C. for 24 hours in a vacuum oven. The particle is rehydrated in 0.05M acetic acid (or in phosphate buffered saline) and mixed with tetanus toxoid antigen at 1-100 μ/ml. Glutaraldehyde (0.25 % final) is added and the mixture is incubated at room temperature for 24 hours. The particles are washed in sterile saline for injection.
Example 2
Human placental collagen, residue B of Play et al (U.S. Pat. No. 4,511,653) is substituted for the bovine hide collagen, in the procedure of Example 1.
Example 3
Insoluble comminuted collagen rich in types III and IV is extracted from bovine lung or kidney, and extracted with 0.05M sodium hydroxide. This collagen is used in place of hide collagen in example 1.
Example 4
Heparin, extracted from intestinal mucosa, is substituted for the C6S in examples 1, 2 or 3.
Example 5
A sheet of freeze dried, dehydrothermally crosslinked porous collagen-GAG is prepared by methods of Yannas with a thickness of 50 μm and a mean pore size of 10 μm. The sheet is rehydrated, tetanus toxoid antigen at 1-100 g/ml is added and the complex is crosslinked with glutaraldehyde as in Example 1. After washing with phosphate buffered saline (PBS), the material is maintained at about 37° C. and 1-5 % w/v agarose with a melting point of about 30°-35° C. is added. The sheet is compressed between absorbent layers to about 1/3 of its original thickness, and is removed from the blotters and chilled to gel the agarose, The material is comminuted to particles of about 17 μm mean diameter, and suspended in chilled saline for injection. The material can be warmed to about 25° C. before injection.
All references named herein are incorporated by reference. While certain preferred embodiments of the invention are disclosed herein, numerous alternative embodiments are contemplated as falling within the scope of the invention. Consequently, this invention is not limited to the specific teachings herein.
Based upon the examples above, the invention described herein is useful for the formulation of vaccines with improved adjuvant activity, targeting an immune response to an antigen and targeting chemical compounds to specific cells or pathogens. | The invention relates to the use of an improved carrier or adjuvant to induce a therapeutic response to a weak antigen. | 0 |
BACKGROUND
[0001] Hammer unions are commonly employed to join pipe segments together. Typically, the wing nut component of the hammer union, which has a wing nut pipe segment with a threaded wing nut having integrated lugs, is tightened onto a male threaded pipe component by hammering upon the lugs. When the wing nut becomes unusable, it is usually necessary to remove the entire wing nut pipe segment from service.
[0002] It is standard practice to capture the wing nut on the wing nut pipe segment which prevents users from removing or replacing the wing nut. Once captured, the wing nut and the wing nut pipe segment are generally inseparable.
[0003] Often, before the full, useful life of the wing nut pipe segment is reached, one or more lugs on the wing nut will become deformed. A wing nut with one or more deformed lugs cannot reliably be mated to a male threaded piece of piping equipment. The piping equipment, however, would generally still be usable if the wing nut is replaced. At this time, there is no safe, field-installable wing nut that can be used to replace deformed, damaged or worn-out wing nuts which are captured on the wing nut pipe segment.
[0004] Currently, when a wing nut becomes deformed due to damaged or deformed lug(s), the end of the wing nut pipe segment on which the wing nut is installed is cut off, the deformed wing nut is replaced with a new wing nut, and the pipe is machined and welded together. Unfortunately, this repair approach often has quality problems. These quality problems lead to safety issues.
[0005] Safety of a joined hammer union is a major concern because hammer unions are often used to connect piping carrying large volumes of fluid under high pressures. Due to the internal forces on the pipe joint, hammer union joints commonly fail in an explosive manner. A misaligned wing nut on a hammer union joint may hold pressure for a period of time, but may ultimately fail as the pressure pushes against the joint.
[0006] An attempted field repair of a wing nut using common cutting and welding techniques creates a significant risk for misaligned or poorly welded joints. In normal field situations, there are few or no field personnel qualified to perform the highly skilled welding and machining operations required for a safe repair. Additionally, there is usually an absence of qualified welding and machining standards for field personnel to follow.
[0007] Since field repairs may result in significant down time, there is also an economic impact when removing a pipe section to replace a deformed wing nut. In manufacturing and drilling operations, down time directly impacts a company's cost of operations.
[0008] As identified herein, there is a need for a field replaceable hammer union wing nut that does not require welding or machining. Additionally, there is a need for a field replaceable hammer union wing nut that may be easily and efficiently installed by field personnel.
SUMMARY OF THE INVENTION
[0009] One embodiment discloses a field replaceable wing nut comprising an arcuate body, an arcuate insert, and an attachment device. The arcuate body defines a first portion of a mounting thread, and the arcuate insert defines a second portion of a mounting thread. The attachment device is for connecting the arcuate body and arcuate insert. When the arcuate body and arcuate insert are connected, the first and second portions of the mounting thread define a complete mounting thread for receiving a threaded male pipe end.
[0010] Another embodiment discloses a multiple piece wing nut comprising a first arcuate body, a second arcuate body, and an attachment device. The first arcuate body has a first threaded portion, and the second arcuate body has a second threaded portion. The attachment device connects the second arcuate body to the first arcuate body. The connected first and second arcuate bodies form an annular body having a collar extending therefrom.
[0011] Still another embodiment discloses a wing nut comprising a first arcuate body, a second arcuate body, and a retaining ring. The first arcuate body has a first portion of a mounting thread thereon. The first arcuate body has a first and second clearance end defining a circumferential gap therebetween. The second arcuate body has a second portion of a mounting thread thereon. The second arcuate body has first and second mating ends for engaging the first and second clearance ends. The retaining ring is disposed about the first and second arcuate bodies. The first and second threaded portions define a complete connecting thread for receiving a threaded male pipe when the first and second arcuate bodies are connected.
[0012] A method is disclosed for replacing a wing nut assembly in the field comprising the following steps:
(a) providing a first arcuate body; (b) radially receiving a pipe on which the wing nut is to be installed through a circumferential gap defined by the first arcuate body; (c) providing a second arcuate body; (d) inserting the second arcuate body in the gap; and (e) securing the first arcuate body to the second arcuate body.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] FIG. 1 is an exploded bottom perspective view of the wing nut.
[0019] FIG. 2 depicts a top plan view of an arcuate body.
[0020] FIG. 3 is a top plan view of the wing nut.
[0021] FIG. 4 is a cross-sectional view taken from FIG. 3 along line 4 - 4 .
[0022] FIG. 5 is an exploded plan view of the wing nut with a pipe section.
[0023] FIG. 6 is a top perspective view depicting the assembled wing nut.
[0024] FIG. 7 is a cross-sectional view of the wing nut installed on a male threaded pipe segment.
DETAILED DESCRIPTION
[0025] This disclosure is directed to a field-installable wing nut that requires no welding or machining operations. The wing nut installation does not require any special qualifications or procedures, and can easily be accomplished by field maintenance personnel in normal field situations.
[0026] Generally, wing nut 10 is selected to correspond to a defined nominal pipe diameter. It is anticipated that a series of wing nuts 10 will be available for different sizes of pipes being employed.
[0027] Referring to FIGS. 1-7 , wing nut 10 is generally comprised of arcuate body 12 , arcuate insert 14 , retaining ring 16 , and attachment devices 18 . Attachment devices 18 are used to connect, or join, arcuate insert 14 with arcuate body 12 . Arcuate body 12 may also be referred to as the first arcuate body 12 , and arcuate insert 14 may also be referred to as the second arcuate body 14 .
[0028] Wing nut 10 is preferably an alloy or carbon steel piece capable of withstanding high pressure when fully assembled and installed. Arcuate body 12 and arcuate insert 14 are preferably manufactured out of the same material. A non-limiting example of the material to form arcuate body 12 and arcuate insert 14 is to use a circular metal slug of hot, rolled grade 4340 steel. Retaining ring 16 is preferably manufactured out of a material different than that of arcuate body 12 and arcuate insert 14 . A non-limiting example is to use grade 4140 steel tubing for retaining ring 16 . Furthermore, retaining ring 16 preferably has material properties with specific capabilities as described herein. Wing nut 10 may be fabricated from other types of materials. These materials are preferably matched to a pipe size, and with a desired pressure containment capability.
[0029] As depicted in the drawings, assembled wing nut 10 defines an annular body 20 with a plurality of lugs 22 thereon. Annular body 20 , which may be referred to as upper ring 20 , has inner diameter 21 and first outer diameter 24 , and in the embodiment shown has three lugs 22 defined thereon. Assembled wing nut 10 has a collar 26 extending longitudinally from annular body 20 . Collar 26 may be referred to as lower ring 26 . Collar 26 has second outer diameter 28 , which is preferably smaller than first outer diameter 24 , so that shoulder 30 is defined by, and extends between, first and second outer diameters 24 and 28 . Wing nut 10 has a length 32 . Collar 26 has a collar length 34 that is shorter than length 32 . Collar 26 has a threaded inner surface 38 extending along collar length 34 to define mounting or connecting threads 40 , and has a collar thickness 42 . Wing nut 10 is thus compatible with a male thread 36 , and will receive a threaded male pipe segment as will be described in more detail herein.
[0030] As depicted in FIG. 2 , arcuate body 12 has an arc that is preferably equal to or greater than arcuate insert 14 , and that is at least circumferentially 180 degrees. The embodiment shown has an arc of approximately 220 degrees. Arcuate insert 14 will complement arcuate body 12 so that when assembled, arcuate body 12 and arcuate insert 14 comprise wing nut 10 .
[0031] Arcuate body 12 has a first clearance end 44 and a second clearance end 46 defining a gap or space 48 therebetween. Gap 48 will receive a pipe segment 50 therethrough. When pipe segment 50 is received through gap 48 , and arcuate body 12 and arcuate insert 14 are connected, the assembled wing nut 10 will provide fluid communication between pipe segments 50 and 52 when connecting threads 40 are properly mated with male threads 36 on pipe segment 52 .
[0032] Arcuate insert 14 has first and second mating ends 54 and 56 . First clearance end 44 of arcuate body 12 will mate with first mating end 54 of arcuate insert 14 . Second clearance end 46 of arcuate body 12 will mate with the second mating end 56 of arcuate insert 14 . First and second seams, or joints 58 and 60 , are formed when arcuate insert 14 is inserted or positioned in gap 48 with first clearance end 44 adjacent to and engaging first mating end 54 , and second clearance end 46 adjacent to and engaging second mating end 56 .
[0033] Joints 58 and 60 are designed to ensure a tight seal between arcuate body 12 and arcuate insert 14 . Thus, it is preferred that joints 58 and 60 have a radially straight seam as depicted in FIGS. 2 , 3 and 6 . Joint 58 preferably has an exemplary angle 62 of about 13 degrees. However, it is understood that angle 62 may be any angle that allows arcuate body 12 and arcuate insert 14 to be joined. Similarly, joint 60 preferably has an exemplary angle 66 of about negative 13 degrees. It is also understood that angle 66 may be any angle that allows arcuate body 12 and arcuate insert 14 to be joined. In FIG. 2 , angles 62 and 66 are measured relative to horizontal centerline 64 .
[0034] Referring to FIG. 5 , attachment openings 68 and 70 are preferably threaded, countersunk attachment openings centered on joints 58 and 60 , and, referring to FIG. 3 , having a radial center point 72 positioned on upper surface 74 of assembled wing nut 10 . Preferably, radial center point 72 is positioned between first outer diameter 24 and inner diameter 21 . Attachment devices 18 are threaded connectors that will hold arcuate body 12 and arcuate insert 14 in place so that connecting threads 40 may receive male thread segment 36 , such as that on pipe segment 52 , to connect pipe segments 50 and 52 .
[0035] Arcuate body 12 and arcuate insert 14 each define a portion of connecting threads 40 as depicted in FIGS. 1 , 6 and 7 . Arcuate body 12 has first thread portion 76 of mounting thread 40 thereon, while arcuate insert 14 has second thread portion 78 of mounting thread 40 thereon. When arcuate body 12 and arcuate insert 14 are connected and aligned, first and second threaded portions 76 and 78 form connecting or mounting thread 40 . The alignment of first and second mounting thread 76 and 78 to form connecting thread 40 is facilitated by the insertion of attachment devices 18 into attachment openings 68 and 70 . In the preferred embodiment, connecting threads 40 are preferably machined into arcuate body 12 and arcuate insert 14 while they are joined. As will be understood, arcuate body 12 and arcuate insert 14 may be threaded prior to being machined from a single piece into the separate arcuate body 12 and arcuate insert 14 . Connecting threads 40 may also be part of a cast or forged wing nut 10 . As described above, connecting threads 40 are located on threaded inner surface 38 of collar 26 .
[0036] In the embodiment shown in FIGS. 1-7 , three lugs 22 are employed. A minimum of one (1) lug 22 is required. The maximum number of lugs 22 is limited by the available circumferential space on annular body 20 . However, it is anticipated that the number of lugs 22 will typically be between two (2) and four (4). Lugs 22 extend radially outward from annular body 20 . The spacing between lugs 22 is not critical in that lugs 22 may be uniformly spaced or not uniformly spaced.
[0037] FIG. 5 depicts a plan view of wing nut 10 with three (3) lugs 22 and wing nut pipe segment 50 . FIG. 5 depicts wing nut pipe segment 50 positioned to be received by arcuate body 12 through gap 48 . In the preferred embodiment, wing nut pipe segment 50 is able to pass through gap 48 without external force applied. In other words, gap 48 has sufficient clearance for pipe segment 50 to pass therethrough.
[0038] Retaining ring 16 , depicted in FIGS. 1 and 7 , is designed to secure arcuate body 12 and arcuate insert 14 in the assembled state. Retaining ring 16 is preferably of a material having properties sufficient to resist the circumferential stress exerted upon it by arcuate body 12 and arcuate insert 14 , once installed. It is preferred that retaining ring 16 have a coefficient of thermal expansion sufficient to allow it to expand to an inner diameter that is greater than second outer diameter 28 of collar 26 when heated. The same coefficient of thermal expansion of retaining ring 16 allows it, when cooled to an ambient temperature, to return to an inner diameter less than second outer diameter 28 of collar 26 . Thus, when retaining ring 16 is heated and placed over collar 26 and then cooled, it will apply inwardly directed radial force to collar 26 , and hold arcuate body 12 and arcuate insert 14 in place. Retaining ring 16 , when installed, will preferably have a thickness 82 about equal to the width 84 of shoulder 30 , and as such will have an outer diameter about the same as first outer diameter 24 of upper ring 20 . Retaining ring 16 preferably has a length similar to collar length 34 of collar 26 .
[0039] A method of installing wing nut 10 may require initially removing a deformed or damaged wing nut from a wing nut pipe segment 50 . The damaged wing nut may be removed at any time prior to installing retaining ring 16 . To install wing nut 10 , arcuate body 12 radially receives pipe segment 50 through gap 48 . Once pipe segment 50 is in place, arcuate insert 14 is inserted into gap 48 so that first and second clearance ends 44 and 46 of arcuate body 12 engage first and second mating ends 54 and 56 of arcuate insert 14 . Attachment devices 18 are threaded into attachment openings 68 and 70 , and are also used to align first and second mounting threads 76 and 78 . Once first and second thread portions 76 and 78 are aligned to form connecting thread 40 , the combined unit of arcuate body 12 and arcuate insert 14 is longitudinally moved along pipe segment 50 until it is positioned at pipe segment end 80 , thereby making collar 26 accessible.
[0040] Retaining ring 16 is heated to a temperature that allows it to expand to an inner diameter greater than second outer diameter 28 of collar 26 . The heated and expanded retaining ring 16 is slipped over collar 26 , and allowed to cool to an ambient temperature. In one non-limiting example, retaining ring 16 is heated to about 400° F. It is preferred that retaining ring 16 be uniformly heated in a field oven or similar device. However, it is also acceptable to heat retaining ring 16 in any manner that creates near uniform thermal expansion without changing the material properties. After retaining ring 16 has radially retracted, pipe segment 52 may be threaded into collar 26 of wing nut 10 . Wing nut 10 is thus a field replaceable wing nut that requires no welding, or machining, and requires no special training of field personnel.
[0041] Thus, it is shown that the apparatus and methods of the present invention readily achieve the ends and advantages mentioned, as well as those inherent therein. While certain preferred embodiments of the invention have been illustrated and described for purposes of the present disclosure, numerous changes in the arrangement and construction of parts and steps may be made by those skilled in the art. All such changes are encompassed within the scope and spirit of the present invention as defined by the appended claims. | A field replaceable wing nut having an arcuate body and an arcuate insert is disclosed. The wing nut is designed to replace an existing wing nut which has deformed or non-useable lugs on a hammer union connection. The wing nut has accurate alignment of the mounting threads using an alignment attachment device. Replacing the wing nut in the field does not require any special equipment or training. Each wing nut is designed for a particular pipe diameter. | 5 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims benefit from provisional application 61/164528 filed Mar. 30, 2009, which is hereby incorporated by reference in its entirety.
BACKGROUND OF THE INVENTION
[0002] Biometrics is the science and technology of measuring and analyzing biological data, such as the imagery of the face or iris. There are 3 problems that need to be overcome with the acquisition of biometric data: (i) ensuring that the biological data is within the field of coverage of one or more of the biometric sensors which is often difficult to control precisely since the sensors may be mounted in different ways for different deployments, and (ii) ensuring that the data is acquired as uniformly as possible so that comparison of data from the same user across different time periods is facilitated, and (iii) ensuring that the user is looking in the vicinity of the camera systems used in any face or iris recognition system
SUMMARY OF THE INVENTION
[0003] The invention comprises three primary elements: (i) a camera configuration whereby two or more cameras are aligned substantially horizontally while the field of coverage is substantially vertical, in order to reduce vertical height of the biometric device, (ii) a pivot mechanism that allows the camera configuration to be moved in unison in order to provide the same vertical field of coverage given different deployment-specific height and angle constraints imposed on the mounting location of the biometric device, and (iii) an attention mechanism comprising a display showing video of a person walking towards the biometric device.
BRIEF DESCRIPTION OF THE DRAWINGS
[0004] FIG. 1 shows prior art whereby multiple cameras are mounted in front of a user at a fixed angle and at a fixed height such that the face of the person is in the field of view of at least one of the cameras. FIG. 2 shows a configuration where a biometric device is mounted above a doorway and covers a region of interest within the doorway. FIG. 3 shows a particular configuration of a biometric device mounted above a doorway comprising an attention mechanism, and three cameras mounted horizontally covering a vertical region of interest. FIG. 4 shows a profile view of a biometric system mounted above a doorway, showing how the region of interest depends on the height H of the device and the tilt Theta of the device. FIG. 5 shows a profile view of a biometric system mounted above a doorway whereby the cameras are mounted on a pivot the angle of which is adjusted by a calibration knob, such that the vertical region of interest of the biometric device can be adjusted on-site depending on deployment-specific constraints on the height and angle of the device.
DETAILED DESCRIPTION OF THE INVENTION
[0005] One existing approach to ensuring that the biological data is within the field of coverage is shown in FIG. 1 (prior art). In this system called Smart Gate (e.g. http://www.abc.net.au/science/news/stories/s1048494.htm), face imagery is acquired by one of 3 cameras mounted vertically in front of a user. The user is asked to stare straight forward at a kiosk, and the cameras are stacked vertically parallel to each other with a large vertical spacing so that the camera closest to the height of the user always captures a frontal view of the face. Ensuring a frontal view of the user facilitates comparison of the same user at a different time period, and improves overall system match performance.
[0006] FIG. 2 shows a different configuration for a biometric system. In this case, the biometric system has to be mounted between the top of a doorway and a ceiling (H1in FIG. 2 ) which is typically 8-12″. In general, the biometric system has to be mounted in a very small vertical space between a lower obstruction and a higher obstruction. Unfortunately, the vertical region of interest of the system, H2, is typically much larger than the vertical space H1 that is available to mount the biometric system. H2is typically 24″ or more. Even if H1is greater than H2such that the cameras in FIG. 1 could be raised above a doorway, then a problem still exists since if the user is asked to look straight ahead or at a fixed point, then a camera view will acquire a vertically skewed, perspective view of the person's face or iris, which makes matching the biometric data much more difficult.
[0007] FIG. 3 shows how the problem has been addressed. First, the cameras are mounted horizontally in the gap H1 rather than vertically. Mounting the cameras horizontally reduces significantly the vertical space occupied, and each camera is tilted and panned carefully to cover a different vertical portion of the region of interest as shown in FIG. 3 by the number of the camera and the number of the region of interest. Second, the horizontal spacing between the cameras is minimized as much as physically possible. A preferred separation is 2″ or 4″. The approach of mounting the cameras horizontally saves vertical space, but it potentially introduces a new problem in that horizontally skewing of the imagery of the subject will occur, in addition to the vertical skewing discussed earlier which as discussed previously makes the matching of the biometric data much more difficult. By mounting the cameras with a close horizontal separation however minimizes the degree of horizontal skewing. Thirdly, an attention-mechanism, such as a video screen showing live video of the user as they use the system, is placed near the cameras. The user is then asked to look at the video screen. Users who are short and are at the bottom of the region of interest will have to look up at a greater tilt angle than users who are tall and are at the top of the region of interest. The benefit of this approach is that vertical skewing of the imagery introduced by the position of the cameras is cancelled out by the user tilting their head to the same vertical height as all the cameras.
[0008] Because the cameras are all at the same height, then the vertical skewing will be cancelled out equally in all camera views. If an attention mechanism at the camera cannot be applied due to the physical constraints of the system, then an alternative more complex solution to this third step is a fore shortening compensation algorithm to remove the vertical skewing.
[0009] While this discussion has focused on allowing a substantially vertical region of interest to be covered using a horizontal arrangement of cameras, alternatively the same method could be used such that a substantially horizontal region of interest is covered using a vertical arrangement of cameras. The cameras could also be pan/tilt/zoom cameras, either moved directly or by means of a mirror.
[0010] FIG. 4 shows a profile view of amount of a biometric system between a ceiling and a doorway. There are two problems with such an installation compared to the installation of a traditional biometric system. First, traditional biometric systems typically have carefully defined specifications that define the precise height that the unit should be mounted above the floor. However, when mounting a system between a ceiling and a doorway, the height of the doorway and the height of the ceiling dictates the vertical positioning, H, of the system, and not the installation manual. Further, the heights of doorways and ceilings vary substantially. This is very problematic since a biometric system designed for a certain vertical region of interest to capture a range of heights will not function properly if mounted at an unspecified height. Further, traditional biometric systems have typically acquired data within a small distance (approximately within 8-12″) so that any slight angle, theta, in the pitch of the device does not move the vertical region of interest substantially. However, more recent biometric systems can acquire data many feet away from the device, and therefore any slight angle, theta, in the pitch of the device can move the vertical region of interest substantially. The slight variations in pitch and height of the device depend on the circumstances that arise during actual installation, such as the flexing of the wall mounting points, and therefore cannot be calculated from site survey measurements with sufficient accuracy to allow adjustment at the factory. We have developed a method that allows an unskilled installation technician to adjust a complex biometric system in a very short period of time, thereby minimizing installation time and cost.
[0011] FIG. 5 shows the solution we have developed. The cameras are all mounted on a single camera module that in turn is mounted on a horizontal pivot. A pivot push bar is attached to the camera module. A housing bar is attached to the case of the biometric system which in turn is attached to the wall or other installation arrangement. A calibration knob comprising a screw thread is screwed through the housing bar and pushes against the pivot push bar. The installation technician installs the biometric unit without having to be concerned substantially with the pitch of the device, and only has to ensure that the device lies within a very broad height range (e.g. 6.5ft-12ft) which can be ascertained from inaccurate and rapid site-survey analysis. The installation technician is then able to adjust the precise vertical region of interest by rotating the calibration knob. Rotating the calibration knob during installation pushes the pivot push bar which in turns rotates the camera module within the housing. The installation technician can adjust the knob and then test performance at different heights in the region of interest. The use of the screwed thread as an adjustment mechanism has the benefit of (i) great precision in adjustment with a wide range of travel (ii) allows the operator to make relative adjustments to allow iterative calibration (e.g. turn the knob one revolution, re-test the biometric system, turn the knob a second revolution) without having to perform a difficult and error prone absolute calibration which may require the participation of a second person which increases cost, or requires additional calibration support materials such as target charts carefully positioned, which take time to set up and are error prone. | A system for reducing the substantially vertical extent of a wide-area biometric system and for reducing the cost and complexity of installation while maintaining high biometric performance, using a substantially horizontally configuration of cameras, preferably with an attention mechanism, and using a precision calibration system that can be used by an unskilled technician and that does not require an accurate site survey or additional materials or equipment. | 6 |
BACKGROUND
[0001] There is a well-recognized need to clean-up contaminants that exist in ground water, i.e., aquifers and surrounding soil formations. Such aquifers and surrounding soil formations may be contaminated with various constituents including organic compounds such as, volatile hydrocarbons, including chlorinated hydrocarbons such as trichloroethene (TCE), and tetrachloroethene (PCE). Other contaminates that can be present include vinyl chloride, 1,1,1 trichloroethane (TCA), and very soluble gasoline additives such as methyltertiarybutylether (MTBE). Other contaminants may also be encountered.
[0002] Ozone sparging is now widely recognized as being one of the more effective oxidation techniques for destroying contaminants that exist in groundwater.
[0003] Other types of contaminants are more recalcitrant. For instance, pharmaceuticals are particularly resistant to decomposition from known techniques including ozone sparging. Pharmaceuticals enter the groundwater from various sources. One source is pharmaceutical laboratories and manufacturing plants located in area with septic systems for waste disposal. Other sources are hospitals and nursing homes.
[0004] Pharmaceutical residuals are increasingly found in sewage discharges. Stronger selective oxidation techniques are necessary to the discharge of antibiotic-resistant bacteria and pharmaceutical residuals into groundwater and surface waters. Zwiener and Frimmel “Oxidative Treatment Of Pharmaceuticals In Water” Water Research 34(6) 1881-1885 (2000); Andreozzi et al. “Paracetanol Oxidation From Aqueous Solutions By Means Of Ozonation and H 2 O 2 UV System” Water Research 37 993-1004 (2003), and Huber et al. “Oxidation Of Pharmaceuticals During Ozonation And Advanced Oxidation Processes” Environmental Science and Technology (2003) have proposed that oxidation systems need to be improved to address the variety of compounds involved. Korhonen et al. Oxidation of Selected Pharmaceuticals in Drinking Water Treatment, Presented at the ninth International Conference on Advanced Oxidation Technologies for Water and Air Remediation Canada (2003) felt that ozone or a combination of ozone and peroxide may offer effective treatment. The identified pharmaceutical residuals include the lipid regulator bezafibrate, antiepileplic carbamazepine, analgesic/inflammatory diclofenac and ibuprofen, and the antibiotic sulfamethoxazole. Even though Korhonen et al. (2003) obtained 90% removal of bezafibrate with ozone alone, H2O2 (peroxide) additional was necessary to obtain over 90% removal of carbamazepine, ibuprofen, and bezafibrate in clean water samples. However, with sewage, the presence of natural organic material (NOM) inhibits effective reaction.
[0005] Another need improved oxidation systems comes from treatment of alkanes and alkenes, common to petroleum products and spills. The bulk of petroleum products are aliphatic long-chain compounds, which are often 75% of the product. In heavier refined products, the carbon chain notation for molecular size, C 5 to C 30 denotes the dominant molecular fractions from 5-carbon to 30-carbon atoms strung together in a single chain. The higher fractions, particularly when branched, are resistant to bacterial action. Fogel (2001) has found that well-aerated samples of petroleum from a diesel source, even when supplied optimal nutrients, will leave about 25% undigested.
SUMMARY
[0006] Ozone has shown a high affinity to attack the alkane fractions. In laboratory testing and field trials, as the ozone concentration has been increased and the size of microbubbles decreased to below micron levels, the efficiency of reactivity has increased to the level beginning to exceed the normal ratio of 1 to 3 molar, or ⅓ of the ozone molecules being involved, common to normal ozone molecular reactions where only the terminal oxygen inserts. It has been thought that secondary biological (bacterial) reactions may be responsible for the ratio approaching 1 to 1 on a mass to mass basis. However, I now believe that there is sufficient basis from laboratory tests to define a newer reactive form of ozone which has become apparent as the bubble size moves from micron size to nano size diameters.
[0007] This may prove particularly capable of removing petroleum chain products and to treat sewage effluent since the long-chain fatty products are known as the common clogger of leaching fields.
[0008] According to an aspect of this invention, the invention provides a new form of reactive ozone and techniques for producing nanobubble suspensions.
[0009] According to a further aspect of this invention, a method includes a method includes forming bubbles having a submicron radius, the bubbles entrapping a high concentration of ozone, with the ozone orienting a net negative charge outwards and a net positive charge inwards.
[0010] According to a further aspect of this invention, a method, includes delivering ozone gas to a diffuser that emits bubbles having a diameter substantially less that 1 micron and selecting conditions under which the ozone gas emanates from the diffuser, entrapped as a gas in the bubbles and having an orientation of negative charge on the surface of the bubbles.
[0011] According to a further aspect of this invention, a method includes a diffuser including a casing, a bubble generator disposed in the casing and a stirrer disposed at an egress of the casing.
[0012] According to a further aspect of this invention, a panel includes an ozone generator, a controller, a metering gas generator/compressor, and a nano bubble solution generator.
[0013] According to a further aspect of this invention, a discharge tube is fed by a nano bubble solution generator in which is disposed an acoustic probe at the end for dissemination of the reactive liquid.
[0014] One or more advantages can be provided from the above.
[0015] The treatment techniques can use bubbles, bubbles with coatings, and directed sound waves to treat volatile organic compounds (VOCs), pharmaceuticals, and other recalcitrant compounds found in drinking water, ground water, sewage, and chemical waste waters. Nano scale reactions should allow a three to tenfold increase in efficiency of reactions which will significantly improve treatment, e.g., reduction of residence contact time, reduction of column height for treatment, etc.
[0016] The new, reactive form of ozone is manifest as a nanoscale film. The arrangements combine new reactive ozone species with dissolved ozone, suspended with nanoscale gaseous ozone. Sonic vibration can be used to restructure the ozone bubbles to allow for sonic vibration of the nanoscale spherical film surfaces to further increase selectivity and reactivity. The addition of coatings of peroxides further enhances reactive radical production of hydroxyl and perhydroxyl species further improving reaction rates.
[0017] With an ex-situ system, the generation of suspended homogenized micro to nanoscale-sized ozone bubble solutions allowing the flow of the reactive liquid into a treatment container (ozone tank or sump) without concern for fouling of a membrane or microporous surface during gas generation. The generator can be supplied with filtered tap water (normally available with 50 psi pressure), an ozone generator, and small pump with house current (120V) and housed in a simple container for application.
[0018] The details of one or more embodiments of the invention are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the invention will be apparent from the description and drawings, and from the claims.
DESCRIPTION OF DRAWINGS
[0019] FIG. 1 is a cross-sectional view showing a sparging treatment system.
[0020] FIG. 2 is a cross-sectional view showing a sparging treatment system with well screen and a multi-fluid diffuser.
[0021] FIG. 3 is a longitudinal cross-section view of a multi-fluid diffuser useful in the arrangement of FIG. 1 .
[0022] FIG. 4 is a longitudinal cross-section view of an alternative multi-fluid diffuser useful in direct injection into shallow contaminant formations.
[0023] FIGS. 5A and 5B are cross-sectional view of sidewalls of the multi-fluid diffuser of FIGS. 3 or 4 showing exemplary construction details.
[0024] FIG. 6 is a diagrammatical plan view of a septic system.
[0025] FIG. 6A is a schematic, elevational view of the septic system of FIG. 6 .
[0026] FIG. 6B is a blown up view of a portion of FIG. 6A .
[0027] FIG. 7 is a diagrammatical, longitudinal cross-section view of an alternative multi-fluid diffuser useful in the arrangements of FIGS. 1 , 2 and 6 .
[0028] FIG. 7A is a blown up view of a portion of FIG. 7 .
[0029] FIG. 8 is a view showing a detail of a ozone treatment chamber and the multi-fluid diffuser of FIG. 7 .
[0030] FIGS. 9 and 9A are diagrammatical views representing a structure of ozone.
[0031] FIG. 10 is a schematic of a nanobubble field generator.
DETAILED DESCRIPTION
[0032] Referring now to FIG. 1 , a sparging arrangement 10 for use with plumes, sources, deposits or occurrences of contaminants, is shown. The arrangement 10 is disposed in a well 12 that has a casing 14 with an inlet screen 14 a and outlet screen 14 b to promote a re-circulation of water into the casing 14 and through the surrounding ground/aquifer region 16 . The casing 14 supports the ground about the well 12 . Disposed through the casing 14 are one or more multi-fluid diffusers, e.g., 50 , 50 ′ (discussed in FIGS. 3 and 4 ) or alternatively in some applications the multi-fluid diffuser 130 ( FIG. 7 ).
[0033] The arrangement 10 also includes a first pump or compressor 22 and a pump or compressor control 24 to feed a first fluid, e.g., a gas such as an ozone/air or oxygen enriched air mixture, as shown, or alternatively, a liquid, such as, hydrogen peroxide or a hydroperoxide, via feed line 38 a to the multi-fluid diffuser 50 . The arrangement 10 includes a second pump or compressor 26 and control 27 coupled to a source 28 of a second fluid to feed the second fluid via feed line 38 b to the multi-fluid diffuser 50 . A pump 30 , a pump control 31 , and a source 32 of a third fluid are coupled via a third feed 38 c to the multi-fluid diffuser 50 .
[0034] The arrangement 10 can supply nutrients such as catalyst agents including iron containing compounds such as iron silicates or palladium containing compounds such as palladized carbon. In addition, other materials such as platinum may also be used.
[0035] The arrangement 10 makes use of a laminar multi-fluid diffuser 50 ( FIG. 3 or FIG. 4 ). The laminar multi-fluid diffuser 50 allows introduction of multiple, fluid streams, with any combination of fluids as liquids or gases. The laminar multi-fluid diffuser 50 has three inlets. One of the inlets introduces a first gas stream within interior regions of the multi-fluid diffuser, a second inlet introduces a fluid through porous materials in the laminar multi-fluid diffuser 50 , and a third inlet introduces a third fluid about the periphery of the laminar multi-fluid diffuser 50 . The fluid streams can be the same materials or different.
[0036] In the embodiment described, the first fluid stream is a gas such as an ozone/air mixture, the second is a liquid such as hydrogen peroxide, and the third is liquid such as water. The outward flow of fluid, e.g., air/ozone from the first inlet 52 a results in the liquid, e.g., the hydrogen peroxide in the second flow to occur under a siphon condition developed by the flow of the air/ozone from the first inlet 52 a.
[0037] Alternatively, the flows of fluid can be reversed such that, e.g., air/ozone from the second inlet 52 a and the liquid, e.g., the hydrogen peroxide flow from first inlet, to have the ozone stream operate under a siphon condition, which can be used to advantage when the arrangement is used to treat deep deposits of contaminants. The ozone generator operating under a siphon condition is advantageous since it allows the ozone generator to operate at optimal efficiency and delivery of optimal amounts of ozone into the well, especially if the ozone generator is a corona discharge type. In this embodiment, the third fluid flow is water. The water is introduced along the periphery of the multi-fluid diffuser 50 via the third inlet.
[0038] Referring to FIG. 2 , an alternate arrangement 40 to produce the fine bubbles is shown. A well casing 41 is injected or disposed into the ground, e.g., below the water table. The casing 41 carries, e.g., a standard 10-slot well-screen 43 . A laminar microporous diffuser 45 is disposed into the casing 41 slightly spaced from the well screen 43 . A very small space is provided between the laminar microporous diffuser 45 and the 10-slot well screen. In one example, the laminar microporous diffuser 45 has an outer diameter of 2.0 inches and the inner diameter of the well casing is 2.0 inches. The laminar microporous diffuser 45 is constructed of flexible materials (described below) and as the laminar microporous diffuser 45 is inserted into the casing 41 it flexes or deforms slightly so as to fit snugly against the casing 41 . In general for a 2 inch diameter arrangement a tolerance of about ±0.05 inches is acceptable. Other arrangements are possible. The bottom of the casing 41 is terminated in an end cap. A silicon stopper 47 is disposed over the LAMINAR SPARGEPOINT® type of microporous diffuser available from Kerfoot Technologies, Inc. and also described in U.S. Pat. No. 6,436,285. The silicone stopper 47 has apertures to receive feed lines from the pumps (as in FIG. 1 , but not shown in FIG. 2 ).
[0039] Exemplary operating conditions are set forth in TABLE 1.
For In-situ Type Applications
[0040]
[0000]
TABLE 1
Laminar
Water
microporous
Operating
Ozone
Hydroperoxide
Flow
Recirculation
diffuser
pressure
Unit
Air
gm/day
gal/day
gal/min
Wells
with screen
(psi)
Wall mount
3–5 cfm
144–430
5–50
1–3
1–4
1–8
0–30
Palletized
10–20 cfm
300–1000
20–200
1–10
1–8
1–16
0–100
Trailer
20–100 cfm
900–5000
60–1000
1–50
1–20
1–40
0–150
[0041] Flow rates are adjusted to a pressure that offsets groundwater hydraulic head and formation backpressures. In general, pressures of, e.g., above 40 psi ambient are avoided so as to prevent fracture or distortion of microscopic flow channels. The percent concentration of hydroperoxide in water is typically in a range of 2-20 percent, although other concentrations can be used. The flow is adjusted according to an estimate of the total mass of the contaminants in the soil and water. If high concentrations (e.g., greater than 50,000 parts per billion in water or 500 mg/kg in soil) of the contaminants are present, sufficient hydroperoxides are added to insure efficient decomposition by the Criegee reaction mechanism or hydrogen peroxide to augment hydroxyl radical formation.
[0042] Extremely fine bubbles from an inner surface of the microporous gas flow and water (including a hydroperoxide, e.g., hydrogen peroxide) are directed by lateral laminar flow through the porous material or closed spaced plates ( FIG. 2 ). The gas to water flow rate is held at a low ratio, e.g., sufficiently low so that the effects of coalescence are negligible and the properties of the fluid remain that of the entering water.
[0043] Alternatively, the water flow is oscillated (e.g., pulsed), instead of flowing freely, both to reduce the volume of water required to shear, and maintain the appropriate shear force at the interactive surface of the gas-carrying microporous material. Johnson et al., Separation Science and Technology, 17(8), pp. 1027-1039, (1982), described that under non-oscillating conditions, separation of a bubble at a microporous frit surface occurs when a bubble radius is reached such that drag forces on the bubble equal the surface tension force πDδ, as:
[0000]
C
D
[
ρ
U
o
2
A
p
2
]
=
π
D
δ
[0000] where C D is the constant analogous to the drag coefficient, ρ is the fluid density, U 0 2 is the fluid velocity, A p is the projected bubble area, π is pi, 3.14, a constant, δ is the gas-water surface tension, and D is the pore diameter of the frit. A bubble is swept from the microporous surface when the bubble radius is reached such that the dynamic separating force due to drag equals the retention force due to surface tension. Bubble distributions of 16 to 30 p (micron) radius and 1 to 4×10 6 bubbles/min can be produced with a gas flow rate of 8 cm 3 /min and rotational water flow rates of 776 cm 3 /min across a microporous surface of μ (micron) pore size with a 3.2 cm diameter surface area. If the flow of liquid is directed between two microporous layers in a fluid-carrying layer, not only is a similar distribution of microbubble size and number of microbubbles produced, but, the emerging bubbles are coated with the liquid which sheared them off.
[0044] In order to decompose certain dissolved recalcitrant compounds, a stronger oxidation potential is necessary for reaction. Ozone in the dissolved form is a recognized strong reagent for dissolved organics but has a short 15 to 30 minute half-life. By reducing the size of gas bubbles to the point where the vertical movement is very low, ozone in a gaseous form can co-exist with dissolved forms as a homogenous mixture. The half-life of gaseous ozone is much longer than dissolved forms, ranging 1 to 20 hours. As the bubbles of ozone become nano size, the surface area to volume ratio exceeds 1.0 and approaches ranges of 5 to 30, thus providing an exceptional capacity to withdraw smaller saturated molecules towards the surfaces from Henry's partitioning. However, the behavior of the nanobubble ozone indicates a new form of ozone where the resonating triatom orients itself to form a membrane which changes surface tension within the water. This allows the production of nano-sized bubbles of ozone which cannot be produced by using air or nitrogen gas under similar conditions of gas flow shear and pressure.
[0045] Characteristics of varying sizes bubbles entrapping ozone are depicted in Table II.
[0000]
TABLE II
Diameter
Surface Area
Volume
Surface Area/
(microns)
4πr 2
4/3 πr 3
Volume
200
124600
4186666
.03
20
1256
4186
0.3
2
12.6
4.2
3.2
.2
.13
.004
32
[0046] In addition to using a continual flow of fluid to shear the outside surfaces on the cylindrical generator, the liquid can be oscillated (pulsed) at a frequency sufficient to allow for fluid replacement in the microporous diffuser, for the volume of liquid removed as coatings on the bubbles, but not allowing interruption of the liquid/bubble column on its way to the surface (or through a slit, e.g., well screen slot). To avoid coalescing of the microbubbles, a continual stream of micro to nanobubbles, actually coated with the peroxide liquid is emitted from the surface of the laminated generator.
[0047] Some examples of gas flows and liquid volumes are listed below in Table III for each of the examples described in FIGS. 1 and 2 .
[0000]
TABLE III
Per 8 cm surface area, (5 μm (micron) porosity)
Rotational
Water Flow
Mean
rates
Bubble size
Bubble size range
Rotative Frequency
10 cm 3 /min gas
(μm)
(μm)
bubbles/min
250 cm 3 /min
30
16–60
4 × 10 6
500 cm 3 /min
20
16–50
7 × 10 6
800 cm 3 /min
15
8–30
15 × 10 6
1500 cm 3 /min
10
5–15
30 × 10 6
3000 cm 3 /min
5
.5–10
50 × 10 6
5000 cm 3 /min
2
.2–6
80 × 10 6
5000 cm 3 /min
<1
.1–5
100 × 10 6
[0048] For an equivalent LAMINAR SPARGEPOINT® type of microporous diffuser available from Kerfoot Technologies, Inc. (formally KV-Associates (2 INCH OUTER DIAMETER)
[0049] For Laminar Spargepoint®
[0050] Porous Surface Area is 119 sq. in. (771 sq. cm.)
[0051] Gas flow 25000 cm 3 /min (25 l/min) or (0.8825 cu. ft/min)=52.9 cu. ft./hr.
[0052] (20 cfm)=1200 cu. ft./hr
(L×0.264=gallons)
[0054] Liquid flow
[0055] If continuous: 625 l/min (165 gallons/min) or 2000 gallons/day
[0056] If oscillate: 5 gallons/day
[0057] The liquid is supplied with a Pulsafeeder® pulsing peristaltic pump to oscillate the liquid (5 psi pulse/sec) and to deliver an adjustable 0.1 to 10 liters/hour (7 to 60 gallons/day).
[0000]
TWO LAMINAR MICROPOROUS MATERIALS
OSCILLATING GAS
GAS FLOW
WATER FLOW
BUBBLE SIZE
FREQUENCY
50 scf
200–800 ccm/min
(μm)
Bubbles/min.
1 cfm
1 L/min (.26
5 μm
10 × 10 8
gallons/min
3 cfm
3 L/min (.78
5 μm
10 × 10 8
gallons/min
30 cfm 1
30 L/min (7.8
5 μm
10 × 10 8
gallons/min
(2 inch 800 sq. cm. LAMINAR SPARGEPOINT ® type of microporous diffuser available from Kerfoot Technologies, Inc. 1
1 Would require ten (10) LAMINAR SPARGEPOINT ® type of microporous diffuser for operation, or increase length or diameter of the microporous diffuser).
[0058] For insertion of the LAMINAR SPARGEPOINT® type of microporous diffuser into well screens or at depth below water table, the flow of gas and liquid is adjusted to the back pressure of the formation and, for gas reactions, the height (weight) of the water column. At ambient conditions (corrected for height of water column), the liquid fraction is often siphoned into the exiting gas stream and requires no pressure to introduce it into the out flowing stream. The main role of an oscillating liquid pump is to deliver a corresponding flow of liquid to match a desired molar ratio of ozone to hydrogen peroxide for hydroxyl radical formation as:
[0000] 2O 3 +H 2 O 2 =2OH.+3O 2
[0059] Set out below are different operating conditions for different types of systems available from Kerfoot Technologies, Inc. (formally KV-Associates, Inc.) Mashpee Mass. Other systems with corresponding properties could be used.
[0060] Wallmount Unit
[0061] Pressure range, injection: 10 to 40 psi
[0062] Gas flow: 1-5 Scfm (50 to 100 ppmv ozone)
[0063] Liquid range: 0.03-0.5 gallons/hr. (55 gallon tank) (3 to 8% peroxide).
[0064] Shearing fluid (water)
[0065] Palletized units
[0066] Pressure range-injection: 10 to 100 psi
[0067] Gas flow: 0-20 cfm (50 to 2000 ppmv ozone)
[0068] Liquid range: 0-5 gallons/hr (3 to 9% peroxide)
[0069] Shearing fluid (water)
[0070] Trailer units
[0071] Pressure range-injection: 10 to 150 psi
[0072] Gas flow: 0-100 cfm (50 to 10,000 ppmv ozone)
[0073] Liquid range: 0-20 gallons/hr (3 to 9% peroxide)
[0074] Shearing fluid (water)
[0075] The process involves generation of extremely fine microbubbles (sub-micron in diameter up to less than about 5 microns in diameter) that promote rapid gas/gas/water reactions with volatile organic compounds. The production of microbubbles and selection of appropriate size distribution optimizes gaseous exchange through high surface area to volume ratio and long residence time within the material to be treated. The equipment promotes the continuous or intermittent production of microbubbles while minimizing coalescing or adhesion.
[0076] The injected air/ozone combination moves as a fluid of such fine bubbles into the material to be treated. The use of microencapsulated ozone enhances and promotes in-situ stripping of volatile organics and simultaneously terminates the normal reversible Henry's reaction.
[0077] The basic chemical reaction mechanism of air/ozone encapsulated in micron-sized bubbles is further described in several of my issued patents such as U.S. Pat. No. 6,596,161 “Laminated microporous diffuser”; U.S. Pat. No. 6,582,611 “Groundwater and subsurface remediation”; U.S. Pat. No. 6,436,285 “Laminated microporous diffuser”; U.S. Pat. No. 6,312,605 “Gas-gas-water treatment for groundwater and soil remediation”; and U.S. Pat. No. 5,855,775, “Microporous diffusion apparatus” all of which are incorporated herein by reference.
[0078] The compounds commonly treated are HVOCs (halogenated volatile organic compounds), PCE, TCE, DCE, vinyl chloride (VC), EDB, petroleum compounds, aromatic ring compounds like benzene derivatives (benzene, toluene, ethylbenzene, xylenes). In the case of a halogenated volatile organic carbon compound (HVOC), PCE, gas/gas reaction of PCE to by-products of HCl, CO 2 and H 2 O accomplishes this. In the case of petroleum products like BTEX (benzene, toluene, ethylbenzene, and xylenes), the benzene entering the bubbles reacts to decompose to CO2 and H2O. In addition, through the production of hydroxyl radicals (.OH) or perhydroxyl radicals (.OOH) or atomic oxygen O ( 3 P) from sonic enhancement, additional compounds can be more effectively attacked, like acetone, alcohols, the alkanes and alkenes.
[0079] Also, pseudo Criegee reactions with the substrate and ozone appear effective in reducing saturated olefins like trichloro ethane (1,1,1-TCA), carbon tetrachloride (CCl 4 ), chloroform and chlorobenzene, for instance.
[0080] Other contaminants that can be treated or removed include hydrocarbons and, in particular, volatile chlorinated hydrocarbons such as tetrachloroethene, trichloroethene, cisdichloroethene, transdichloroethene, 1-1-dichloroethene and vinyl chloride. In particular, other materials can also be removed including chloroalkanes, including 1,1,1 trichloroethane, 1,1, dichloroethane, methylene chloride, and chloroform, O-xylene, P-xylene, naphthalene and methyltetrabutylether (MTBE) and 1,4 Dioxane.
[0081] Ozone is an effective oxidant used for the breakdown of organic compounds in water treatment. The major problem in effectiveness is that ozone has a short lifetime. If ozone is mixed with sewage containing water above ground, the half-life is normally minutes. To offset the short life span, the ozone is injected with multi-fluid diffusers 50, enhancing the selectiveness of action of the ozone. By encapsulating the ozone in fine bubbles, the bubbles would preferentially extract volatile compounds like PCE from the mixtures of soluble organic compounds they encountered. With this process, volatile organics are selectively pulled into the fine air bubbles. The gas that enters a small bubble of volume (4πr 3 ) increases until reaching an asymptotic value of saturation.
[0082] The following characteristics of the contaminants appear desirable for reaction:
[0083] Henry's Constant: 10 −1 to 10 −5 atm-m 3 /mol
[0084] Solubility: 10 to 10,000 mg/l
[0085] Vapor pressure: 1 to 3000 mmHg
[0086] Saturation concentration: 5 to 100 g/m 3
[0087] The production of micro to nano sized bubbles and of appropriate size distribution are selected for optimized gas exchange through high surface area to volume ratio and long residence time within the area to be treated.
[0088] Referring now to FIG. 3 , a multi-fluid diffuser 50 is shown. The multi-fluid diffuser 50 includes inlets 52 a - 52 c , coupled to portions of the multi-fluid diffuser 50 . An outer member 55 surrounds a first inner cylindrical member 56 . Outer member 55 provides an outer cylindrical shell for the multi-fluid diffuser 50 . First inner cylindrical member 56 is comprised of a hydrophobic, microporous material. The microporous material can has a porosity characteristic less than 200 microns in diameter, and preferable in a range of 0.1 to 50 microns, most preferable in a range of 0.1 to 5 microns to produce nanometer or sub-micron sized bubbles. The first inner member 56 surrounds a second inner member 60 . The first inner member 56 can be cylindrical and can be comprised of a cylindrical member filled with microporous materials. The first inner member 56 would have a sidewall 56 a comprised of a large plurality of micropores, e.g., less than 200 microns in diameter, and preferable in a range of 0.1 to 50 microns, most preferable in a range of 0.1 to 5 microns to produce nanometer or sub-micron sized bubbles.
[0089] A second inner member 60 also cylindrical in configuration is coaxially disposed within the first inner member 56 . The second inner member 60 is comprised of a hydrophobic material and has a sidewall 60 a comprised of a large plurality of micropores, e.g., less than 200 microns in diameter, and preferable in a range of 0.1 to 50 microns, most preferable in a range of 0.1 to 5 microns to produce nanometer or sub-micron sized bubbles. In one embodiment, the inlet 52 a is supported on an upper portion of the second inner member 60 , and inlets 52 b and 52 c are supported on a top cap 52 and on a cap 53 on outer member 55 . A bottom cap 59 seals lower portion of outer member 55 .
[0090] Thus, proximate ends of the cylindrical members 56 and 60 are coupled to the inlet ports 52 b and 52 a respectively. At the opposite end of the multi-fluid diffuser 50 an end cap 54 covers distal ends of cylindrical members 56 and 60 . The end cap 54 and the cap 52 seal the ends of the multi-fluid diffuser 50 . Each of the members 55 , 56 and 60 are cylindrical in shape.
[0091] Member 55 has solid walls generally along the length that it shares with cylindrical member 60 , and has well screen 57 (having holes with diameters much greater than 200 microns) attached to the upper portion of the outer member. Outer member 55 has an end cap 59 disposed over the end portion of the well-screen 57 . The multi-fluid diffuser 50 also has a member 72 coupled between caps 54 and 57 that provide a passageway 73 along the periphery of the multi-fluid diffuser 50 . Bubbles emerge from microscopic openings in sidewalls 60 a and 56 a , and egress from the multi-fluid diffuser 50 through the well screen 57 via the passageway 73 .
[0092] Thus, a first fluid is introduced through first inlet 52 a inside the interior 75 of third member 60 , a second fluid is introduced through the second inlet 52 b in region 71 defined by members 56 and 60 , and a third fluid is introduced through inlet 52 c into an outer passageway 73 defined between members 53 , 55 , 56 , and 59 . In the system of FIG. 1 , the first fluid is a gas mixture such as ozone/air that is delivered to the first inlet through central cavity 75 . The second fluid is a liquid such as hydrogen peroxide, which coats bubbles that arise from the gas delivered to the first inlet, and the third fluid is a liquid such as water, which is injected through region 73 and acts as a shearing flow to shear bubbles off of the sidewall 56 a . By adjusting the velocity of the shearing fluid, bubbles of very small size can be produced (e.g., sub-micron size). Of course adjusting the conditions and porosity characteristics of the materials can produce larger size bubbles.
[0093] Referring to FIG. 4 , an alternative embodiment 50 ′ has the cylindrical member 56 terminated along with the member 60 by a point member 78 . The point member 78 can be used to directly drive the multi-fluid diffuser into the ground, with or without a well. The point member can be part of the cap 59 or a separate member as illustrated.
[0094] The multi-fluid diffuser 50 or 50 ′ is filled with a microporous material in the space between members 56 and 60 . The materials can be any porous materials such as microbeads with mesh sizes from 20 to 200 mesh or sand pack or porous hydrophilic plastic to allow introducing the second fluid into the space between the members 56 and 60 .
[0095] In operation, the multi-fluid diffuser 50 is disposed in a wet soil or an aquifer. The multi-fluid diffuser 50 receives three fluid streams. In one embodiment, the first stream that is fed to the inlet 52 a is a liquid such as water, whereas second and third streams that feed inlets 52 b and 52 c are hydrogen peroxide and a gas stream of air/ozone. The multi-fluid-diffuser 50 has water in its interior, occasioned by its introduction into the aquifer. The air ozone gas stream enters the multi-fluid diffuser 50 and diffuses through the cylindrical member 56 as trapped microbubbles into the space occupied by the microporous materials where a liquid, e.g., hydrogen peroxide is introduced to coat the microbubbles. The liquid stream through the microporous materials is under a siphon condition occasioned by the introduction of water through the periphery of the multi-fluid diffuser 50 . The flow of water in additional to producing a siphoning effect on the liquid introduced through inlet 52 b also has a shearing effect to shear bubbles from the microporous sides of the cylindrical member 60 , preventing coalescing and bunching of the bubbles around micropores of the cylindrical member 60 . The shearing water flow carries the microbubbles away through the well screen disposed at the bottom of the multi-fluid diffuser 50 .
[0096] Referring now to FIGS. 5A , 5 B, exemplary construction details for the elongated cylindrical members of the multi-fluid diffusers 50 or 50 ′ and the laminar microporous diffuser 45 are shown. As shown in FIG. 5A , sidewalls of the members can be constructed from a metal or a plastic support layer 91 having large (as shown) or fine perforations 91 a over which is disposed a layer of a sintered i.e., heat fused microscopic particles of plastic to provide the micropores. The plastic can be any hydrophobic material such as polyvinylchloride, polypropylene, polyethylene, polytetrafluoroethylene, high-density polyethylene (HDPE) and ABS. The support layer 91 can have fine or coarse openings and can be of other types of materials.
[0097] FIG. 5B shows an alternative arrangement 94 in which sidewalls of the members are formed of a sintered i.e., heat fused microscopic particles of plastic to provide the micropores. The plastic can be any hydrophobic material such as polyvinylchloride, polypropylene, polyethylene, polytetrafluoroethylene, high-density polyethylene (HDPE) and alkylbenzylsulfonate (ABS). Flexible materials are desirable if the laminar microporous diffuser 45 is used in an arrangement as in FIG. 2 .
[0098] The fittings (i.e., the inlets in FIG. 2 ,) can be threaded and/or are attached to the inlet cap members by epoxy, heat fusion, solvent or welding with heat treatment to remove volatile solvents or other approaches. Standard threading can be used for example NPT (national pipe thread) or box thread e.g., (F480). The fittings thus are securely attached to the multi-fluid diffuser 50 s in a manner that insures that the multi-fluid diffuser 50 s can handle pressures that are encountered with injecting of the air/ozone.
[0099] Referring to FIGS. 6 and 6A , a septic system 110 is shown. The septic system includes a septic tank 112 , coupled to a leach field 114 having perforated distribution pipes or chambers (not shown) to distribute effluent from the tank 112 within the leach field. The tank can be coupled to a residential premises or a commercial establishment. In particular, certain types of commercial establishments are of particular interest. These are establishments that produce effluent streams that include high concentration of pharmaceutical compounds, such as pharmaceutical laboratories and production facilities, hospitals and nursing homes.
[0100] The leach field 114 is constructed to have an impervious pan, 116 spaced from the distribution pipes by filter media 122 ( FIG. 6A ). The pan is provided to intercept and collect water from filter media 122 in the leach field after treatment and deliver the water and remaining contaminants via tube 117 to an ozone treatment tank 118 . The water may still have high concentrations of nitrogen containing compounds and pharmaceutical compounds. The ozone treatment tank 118 is disposed between the leach field 120 and the final leach field 114 . The first phase of treatment may also employ a denitrification system with 1 or 2 leaching fields. The ozone treatment tank 118 temporarily stores the collected water from the pan 116 . The ozone treatment tank 118 has an in-situ microporous diffuser, such as those described in FIGS. 3 , 4 or receives a solution from a diffuser 130 described in FIG. 7 , below, to inject air/ozone in the form of extremely small bubbles, e.g., less than 20 microns and at higher ozone concentrations. In addition, the diffuser ( FIG. 7 ) is configured to supply the air/ozone in stream of water that comes from an external source rather than using the effluent from the leach field 114 to avoid clogging and other problems.
[0101] In another embodiment ( FIG. 6A ), the bubble generator system is disposed outside of the tank 118 and has a tube 123 that feeds a porous mixing chamber 125 (static or with a stirrer) at the bottom of the tank 180 . Acoustic probes, e.g., 121 can be disposed within the tips of the tubes, as shown in FIG. 6B at the egress of tube 123 and as shown in phantom at the ingress of tube 123 , to further agitate and shape the bubbles. Other embodiments as shown in FIG. 8 can have the bubble generator disposed in the tank 118 .
[0102] Referring now to FIG. 7 , a diffuser 130 includes a bubble generator 132 disposed within a container, e.g., a cylinder 134 having impervious sidewalls, e.g. plastics such as PVDF, PVC or stainless steel. In embodiments with magnetic stirrers, the walls of the container, at least those walls adjacent to the magnetic stirrer are of non-magnetic materials.
[0103] The bubble generator 132 is comprised of a first elongated member, e.g., cylinder 132 a disposed within a second elongated member, e.g., cylinder 132 c . The cylinder 132 a is spaced from the cylinder 132 c by microporous media, e.g., glass beads or sintered glass having particle sized of, e.g., 0.01 microns to 5.0 microns, although others could be used. Fittings 133 a and 133 b are disposed on a cap 133 to received fluid lines (not numbered). A bottom cap 135 seals end portions of the cylinders 132 a and 132 b . The cylinders 132 a and 132 c are comprised of sintered materials having microporosity walls, e.g., average pore sizes of less than one micron. The sintered cylinder 132 b or bead material with diameters of 1 to 100 microns, with a porosity of 0.4 to 40 microns, receives liquid.
[0104] Disposed in a lower portion of the cylindrical container 134 is a stirring chamber 140 provided by a region that is coupled to the cylindrical container 134 via a necked-down region 138 . This region, for use with a magnetic stirrer, is comprised on non-magnetic materials, other that the stirring paddle. Other arrangements are possible such as mechanical stirrers. The stirring chamber supports a paddle that stirs fluid that exits from the necked down region 138 of cylindrical container 134 and which in operation causes a vortex to form at the bottom of the necked down region 138 and below the generator 132 . A magnetic stirrer 144 is disposed adjacent the stirring chamber 140 . Alternatively the stirrer can be as shown as the stirrer with electric coil (not numbered).
[0105] A second necked down region 146 couples the stirring chamber 140 to an exit port 150 . Disposed in the exit port 150 is an adjustable valve 148 . The adjustable valve is used to adjust the fluid flow rate out of the diffuser 130 to allow the egress rate of fluid out of the diffuser 130 to match the ingress rate of fluid into the diffuser 130 . As shown in detail in FIG. 7A the stirrer 142 has shafts that are coupled to a pair of supports 141 a within the stirring chamber 140 , via bearings 142 b or the like. Other arrangements are possible. The supports are perforated, meaning that they have sufficient open area so as not to inhibit flow of fluids. The supports can be perforated disks, as shown, or alternatively bars or rods that hold the bearings and thus the shafts for stirrer in place.
[0106] Referring now to FIG. 8 , the diffuser 130 is disposed in the ozone contact tank 130 . In operation, water or another liquid (e.g., Hydrogen Peroxide especially for sparging applications of FIGS. 1 and 2 ) is delivered to one port 133 c of the generator 132 via tubing, not referenced. A dry air+Ozone stream is delivered to the other port 133 a of the generator 132 . As the air+ozone stream exits from walls of the cylinder 132 a the air+ozone is forced out into the microporous media 132 b where the air+ozone come in contact with the liquid delivered to port 132 c . The liquid meets the air+ozone producing bubbles of air+ozone that are emitted from the bubble generator 132 , as part of a bubble cloud of the stream of water.
[0107] The stirring action provided by the stirrer 140 produces a vortex above the stirrer 140 with cavitation of the liquid stream, producing nano size bubbles. The ideal liquid velocity is maintained at greater than 500 cc/min across a 1 micron porosity surface area of 10 cm 2 . The stirrer maintains a rotational flow velocity of greater than 500 cm 3 /min per 8 cm surface area, maintaining a porosity less than 5 microns.
[0108] In one arrangement, the sidewalls of the tubes have a porosity of 5 to 0.5 μm (microns), and the interstitial portion that receives liquid and has glass beads of diameter 0.1 mm or less. The sidewalls can be of sintered glass, sintered stainless steel, a ceramic or sintered plastics, such as polyvinyl chloride (PVC), high density polyethylene (HDPE), polyfluorocarbons (PVDF), Teflon.
[0109] The diffuser 130 can be continuously fed a water stream, which produces a continuous outflow of submicron size bubbles that can be directed toward a treatment, which is an advantage because the bubble generator 132 inside the diffuser 130 is not exposed to the actual waters being treated and therefore the generator 132 will not foul in the water being treated.
[0110] Referring now to FIG. 9 , a depiction of a unique bubble arrangement that occurs under specified conditions with gaseous ozone provided within extremely fine bubbles at relatively high ozone concentrations, e.g., ozone from 5 to 20% concentration with the balance air e.g., oxygen and nitrogen is shown. The arrangement has ozone, which has a polar structure of tri-atomic oxygen (ozone), forming constructs of spherical reactive “balls.” As depicted, for a single slice of such a spherical ball, the ozone at the interface boundary of the gas with the water has a surface in which the ozone molecule is aligned and linked. These constructs of ozone allow very small 20 to 20,000 nanometer bubble-like spheres of linked ozone molecules to form in subsurface groundwater, which are not believed possible for simple bubbles of air alone or air with ozone at lower concentrations, due to high surface tension.
[0111] The structure shown in FIG. 9 contains gaseous ozone and air on the inside and an ozone membrane arrangement like a micelle on the gas-water interface, as shown.
[0112] As bubbles of ozone become smaller and smaller, e.g., from micron to nano size bubbles, the ozone content in the bubbles aligns, meaning that the ozone molecules on the surface of the bubble, i.e., adjacent water, orient such that the predominantly the outer oxygen atoms (negative charge) align outwards, whereas the center oxygen atom (positive or neutral charge) aligns inward.
[0113] The interface between the aligned ozone molecules and surrounding water provides a reactive skin zone or interface. In this structure it is believed that the ozone “sticks” to the surface film of the water to re-orientate itself. In this orientation the ozone can resonate between two of the four theorized resonance structures of ozone, namely type II and type III (See FIG. 9A ), whereas when the ozone comes in contact with a contaminant, it may switch to the more reactive forms types IV and V donating electrons to decompose the contaminate. A terminal oxygen atom thus can become positively charged so as to act as an electrophilic to attack a nucleophilic site of an organic molecule. All of the four resonance structures have a negatively charged terminal oxygen atom causing ozone to act as a nucleophile to attack an electrophilic site on an organic molecule. Ozone acting as a nucleophile can attack electron deficient carbon atoms in aromatic groups. Structures IV and V where ozone acts like a 1,3 dipole undergoes 1,3 dipole cycloaddition with unsaturated bonds to result in a classical formation of the Criegee primary ozonide.
[0114] The membrane (skin-like) structure of the ozone depicted in FIG. 9 can be a formidable resonance reactor because as volatile organic compounds are pulled into the structure (according to Henry's law) when the compounds come in contact with the skin-like structure electron flow can quickly proceed for substitution reactions. With excess ozone gas in the bubble, replacement of the lost ozone in the skin layer of the bubble is quick.
[0115] The resonance hybrid structure of the ozone molecule has an obtuse angle of 116° 45″±35″ and an oxygen bond length of 1.27 Å (about 0.13 nm). Trambarolo, et al., (1953) explained that the band length was intermediate between the double bong length in O 2 (1.21 Å) and the single bond length in hydrogen peroxide H 2 O 2 (1.47 Å). The resonance hybrid can be thought of orienting with the negative (−) charge outwards and the positive charge inwards with linkage occurring similar to Kekule' structure of carbon by alternating resonance forms among the aligned bonding electrons. This structure of the ozone changes surface tension with water to produce extremely fine micro to nanobubbles unable to be formed with air (nitrogen/oxygen gas) alone.
[0116] The surface properties of the ball structure promote the formation of a reactive surface equivalent to hydroxyl radicals or found with thermal decomposition of ozone in collapsing cavitation bubbles of sonolytic systems. The reactivity with organic contaminants such as alkanes or 1,4 Dioxane may approach or exceed the reactivity of ozone and peroxide addition, known to produce hydroxyl radicals.
[0117] The basis for this discovery includes observed changes in surface tension, allowing smaller and smaller bubbles with increasing ozone concentration. In addition, the equivalent reactivity of the nano-micro bubbles with that of hydroxyl radical formers is greater. For example, the reactivity is unquenched with carbonate addition where hydroxyl radical reactions are quickly quenched. In addition, the ozone has an increased capacity to react with ether-like compounds such as MTBE and 1,4 Dioxane compared to what would be expected.
[0118] For example, Mitani, et al., (2001) determined in a laboratory study that if O 3 alone were used to remediate MTBE, then increased residence time, temperature, or O 3 concentration was necessary to completely oxidize MTBE to carbon dioxide. Generally, it is assumed that the initial OH. attack on MTBE by H. abstraction occurs at either methoxy group or any of the three methyl groups. The O—H bond energy is higher than that of the C—H bond of an organic compound, resulting in OH. indiscriminately abstracting hydrogen from organic compounds (Mitani, et al., 2001).
[0119] The direct bubbling of ozone from the microporous diffuser 50 ( FIGS. 3 , 4 ), where a liquid is forced through simultaneously with ozone gas or the diffuser 130 ( FIG. 7 ) produces stable submicron-sized bubbles. The mean size of the bubbles can be checked by measuring the rise time of an aerosol-like cloud of such bubbles in a water column.
[0120] The unique spherical formation would explain a certain amount of previously unexplainable unique reactivities (with alkane fractions, for example). The reactivity of the microfine ozone bubbles with linear and branched alkanes would be a possible explanation for such low ratios of molar reactivities.
[0121] The size of bubbles would run from twenty nanometers (nm) or smaller up to about 20 microns (20,000 nm) in size. At 20 microns, the ozone concentration would be in a range of about 1% up to a maximum of 20%, whereas at the smaller size bubbles can be less, e.g., from 1% to 20% at the higher end to less than 1% because of higher surface area. Another range would be twenty nanometers (nm) or smaller up to about 1 micron in size with 1 to 10% ozone concentration. Normally, a 20 micron sized porosity microporous diffuser will produce bubbles of about 50 microns in diameter and thus smaller porosity microporous diffusers would be used or the arrangements discussed below to produce the smaller bubbles.
[0122] Possibly the entire surface area of the bubbles need not be occupied completely with the ozone molecules in order to start observing this effect. At as little as 10% (85% oxygen, balance nitrogen) of the surface area of the bubbles need be covered by ozone in order for the effect to start occurring.
[0123] The oxygen atoms in the ozone molecule have a negative charge which allows the oxygen atoms to break into smaller bubbles in water by changing surface tension. The ozone undergoes a structural change by orienting the negative and positive charges. The ozone structures have resonance structure and the ozone in the form of a gas with water molecules, could preferentially take an orientation that places the polar bonded oxygen atoms towards the water and the central oxygen atoms towards the middle of the bubbles, with the interior of the bubbles filled with ozone and air gases.
[0124] Certain advantages may be provided from this type of structure with respect to treating organic contaminants.
[0125] Because of the resonant structure of ozone, this structure appears to be inherent more reactivity than is normally associated with dissolved molecular ozone. Conventionally mixing hydrogen peroxide with ozone is thought to produce hydroxyl radicals and a concomitant increase in oxidative potential. When formed in water, however, the reactivity of hydrogen peroxide and ozone with certain materials appears to be far superior to that of normal hydroxyl radical formation. This can be particularly event with ether-like compounds and with simple carbon lineages like the octanes and hexanes.
[0126] The level of reactivity cannot be explained simply by increases in the surface to volume ratio that would occur when ozone is placed in smaller and smaller structures. The reactivity that occurs appears to be a heightened reactivity where the ozone itself is competing with ozone plus peroxide mixtures, which are normally thought to create the hydroxyl radical which has usually at least two orders of magnitude faster reactivity than dissolved molecular ozone. It is entirely possible that through the reinforcement of the resonation of the molecules of the oxygen that the way the ozone is arranged the ozone can direct more efficient reaction upon contact than individual tri-molecular ozone. Thus, less moles of ozone are need to produce a reaction with a particular compound. This form of ozone has a reactive-like surface structure.
[0127] As the bubbles get finer and finer it is difficult to measure their rate of rise because they go into motion can are bounced around by the water molecules. It is possible that bubbles that are too small might become unstable because the total number of linkages is not stable enough.
[0128] Pharmaceutical compounds are a particular good target for this enhanced reactive ozone, because pharmaceutical compounds are difficult compounds to decompose.
[0129] Referring to FIG. 10 , a nanobubble generator 150 that can be deployed in field operations is shown. The nanobubble generator 150 includes an ozone generator 152 fed via, e.g., dry air or oxygen, a nanobubble solution generator 154 fed liquid, e.g., water or hydrogen peroxide and ozone/air or ozone/oxygen from a compressor 156 . Liquid is output from the nanobubble solution generator 154 and includes a cloud of nanobubbles, and is delivered to a bank of solenoid controlled valves 158 to feed tubes 159 that can be disposed in the contact tanks ( FIG. 6A or wells). The feed tubes 159 can have acoustic or sonic probes 123 disposed in the tips, as shown. A controller/timer 153 controls the compressor and solenoid control valves. A excess gas line 155 is connected via a check valve 157 between nanobubble solution generator 154 and the line from the ozone generator to bleed off excess air from the nanobubble solution generator 154 .
[0130] A number of embodiments of the invention have been described. Nevertheless, it will be understood that various modifications may be made without departing from the spirit and scope of the invention. | Disclosed is a new form of reactive ozone and techniques for producing nanobubble suspensions of the reactive ozone. The bubbles entrap a high concentration of ozone, with the ozone orienting a net negative charge outwards and a net positive charge inwards. | 2 |
BACKGROUND OF THE INVENTION
This invention relates to a cover for a manhole structure and more particularly to such a cover which requires a minimum of metal to provide the required strength with the overall weight of the composite cover being of a predetermined minimum weight.
As is well known in the art to which our invention relates, manhole covers are exposed to heavy traffic and must be of a certain minimum weight or else must be secured to the manhole frames by suitable securing means in order to prevent them from becoming dislodged by vehicles passing thereover. Heretofore, this required minimum weight of the manhole cover has been attained by the use of conventional cast iron supporting structures. Now that it is possible to reduce the weight of manhole covers by the use of high strength materials and improved designs, the weight of such covers are often considerably below the minimum weight required to hold the same in place without additional securing means.
SUMMARY OF THE INVENTION
In accordance with our invention, we provide a cover for manhole structures which provides all of the advantages of a cast iron supporting structure with a requirement of less metal while still providing a cover which is heavy enough to permit its insertion in a manhole frame without the use of fastening means. Our improved manhole cover is provided by an improved design of the metal portion thereof and the use of high strength materials whereby the amount of metal is reduced to a minimum, while the weight of a concrete portion of the cover is so selected that together with the weight of the metal portion it will at least add up to the required minimum weight. Accordingly, by designing the metal portion whereby it absorbs the full traffic load, the concrete portion may be constructed as a non-supporting component for the purpose of adding weight only.
DESCRIPTION OF THE DRAWINGS
A cover for manhole structures embodying features of our invention is illustrated in the accompanying drawings, forming a part of this application, in which:
FIG. 1 is a vertical sectional view, partly broken away, showing one form of our invention with the manhole cover mounted in a supporting frame;
FIG. 2 is a fragmental, bottom plan view of the manhole cover shown in FIG. 1 showing a portion of the manhole cover removed from the supporting frame for the manhole cover; and,
FIG. 3 is a vertical sectional view showing another embodiment of our invention and showing a portion of the manhole assembly which surrounds the supporting frame for the manhole cover.
DETAILED DESCRIPTION
Referring now to the drawings for a better understanding of our invention, we show a manhole cover 10 which is mounted in a suitable supporting frame 11 which defines the upper end of a manhole assembly indicated generally at 12. As shown in FIG. 1, the cover 10 comprises a cast iron supporting structure which is of an extremely light-weight construction so as to save material. This structure is made possible due to the improved high-strength design and the characteristics of the material used, such as spheroidal graphite iron. The cast iron support structure is shown as comprising an upwardly opening, tub-shaped member 13 which is formed integrally with an annular peripheral member 14. Radially extending reinforcing ribs 16 extend between the annular member 14 and the lower side of the tub-shaped member 13, as shown. Also, suitable vent openings 20 may be provided in the cover 10, as shown. The under surface of the peripheral edge of the annular member 14 engages and is supported by arcuate support members 18 which are carried by the support structure 11. As shown in FIG. 1, the support structure 11 may be provided with spaced apart vertical members 17.
The upwardly opening, tub-like member 13 supports a concrete filling 19 which comprises a heavy concrete having a specific gravity which is greater than the specific gravity of conventional concrete compositions. Accordingly, the weight of the concrete filling 19 compensates for a weight deficiency of the cast iron supporting structure for the manhole cover 10 without offsetting the material costs saved by the use of a light-weight metal structure. As shown in FIG. 1, transverse cross members 21 may be formed within the tub-like member 13 to reinforce the cover and also to retain the concrete filling 19 in place.
The weight loss resulting from the reduction of material used for the cast iron supporting structure 10 is thus compensated for by the use of the concrete filling 19 which contains extra heavy aggregates. The cost of production of such concrete is more than offset by the material cost saved in the production of a light-weight cast iron supporting structure. Accordingly, our improved manhole cover is much less expensive and at the same time meets the minimum weight requirements for holding the cover in place during use.
The heavy aggregates in the concrete filling 19 may comprise shredded cast iron scrap, red iron ore, barium sulfate and the like. Such materials have a sufficiently high specific gravity to provide the total weight required for the manhole cover. Furthermore, such materials pose no problems concerning thermal expansion since these aggregates agree in this respect with the remaining constituents of the concrete filling 19 and the metal supporting structure 10. The aggregates may be used separately or combined with each other with the selection depending upon the cost of the various aggregates at the construction site. Preferably, the amount of aggregates used should be so related to their specific gravity that the specific gravity of the concrete filling will amount to 4-6 kg/dm 3 . That is, the concrete thus produced ranges from two to three times the specific gravity of ordinary concrete. The concrete filling 19 may be made with an aggregate such as a mixture of cast iron scrap and barium sulfate with the specific weight of the barium sulfate being 4.3 and that of the cast iron being 7.2 so as to produce a concrete having a specific weight of 5 kg/dm 3 . Accordingly, the specific weight of the material used to make the cover will exceed a required minimum weight to 300 kg/m 2 .
Referring now to FIG. 2 of the drawings, we show a manhole comprising a supporting structure 10 a made of high-tensile strength material. The supporting structure 10 a is shown as being in the form of a relatively flat plate-like member 22 with the upper surface thereof being provided with anti-skid knobs 23 or similar protuberances. The lower surface of the plate-like member 22 supports a concrete slab 24 which is secured to the plate-like member 22 by suitable anchoring means, such as suitable reinforcing bars 26 which may be formed of iron. Since the concrete slab 24 depends from the plate-like member 22, it performs no supporting function whereby it serves only to increase the weight of the cover. It will be understood that in this embodiment the concrete also contains heavy aggregates so as to maintain the dimensions of the concrete slab 24 within the necessary limits. As shown in FIG. 3, the concrete slab 24 is of a width to be positioned inwardly of vent openings 27 carried by the plate-like member 22.
From the foregoing it will be seen that we have provided an improved cover for manhole structures which provides all of the advantages of a cast iron supporting structure while reducing the amount of metal materials employed and still providing a cover which is heavy enough to permit its insertion in manhole frames without the use of fastening means.
While we have shown our invention in two forms, it will be obvious to those skilled in the art that it is not so limited, but is susceptible of various other changes and modifications without departing from the spirit thereof. | A cover for manhole structures embodying a metal portion constructed of high strength material and assembled to provide maximum strength with a minimum of weight. A concrete portion is carried by the metal portion with the weight of the concrete portion being so proportioned relative to the weight of the metal portion that the combined weight thereof provides a manhole cover of a predetermined minimum weight. | 4 |
This application is a continuation of U.S. patent application Ser. No. 13/829,992, filed on Mar. 14, 2013, which claims the benefit of U.S. Provisional Application No. 61/730,977, filed on Nov. 29, 2012, the Korean Patent Application Nos. 10-2013-0009050, filed on Jan. 28, 2013 and 10-2013-0020481, filed on Feb. 26, 2013, which are all hereby incorporated by reference as if fully set forth herein.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present specification relates to a mobile device and a method for controlling the same, and more particularly, to a mobile device and a method for controlling the same, in which different lock states are provided depending on a mode which is currently being implemented in a dual mode of a child mode and an adult mode and different unlock interfaces are provided depending on the lock state which is set.
2. Discussion of the Related Art
With the development of electronic devices and communication technologies, users could perform various functions that include text message transmission and reception functions and phone communication by using a mobile device. In particular, with the mass spread of smart phones, various applications have been developed together. Accordingly, the users could install an application having a desired function in the mobile device and perform various functions such as games and Internet banking.
In particular, various animation applications that play animations which children like and various children's song applications that play children's songs which children like have been provided recently. Accordingly, a user who is a mother or father of a child may implement animation applications or children's song applications installed in his/her mobile device to allow the child to use the applications.
However, when the child is using the mobile device of the user, a call or text message for a task of the user may be received. At this time, if the child of the user receives the call or text message, a problem occurs in that the user may miss an important contact. Particularly, if the child is too young, such a problem may be likely to occur.
SUMMARY OF THE INVENTION
Accordingly, the present specification is directed to a mobile device and a method for controlling the same, which substantially obviate one or more problems due to limitations and disadvantages of the related art.
An object of the present specification is to provide a mobile device and a method for controlling the same, in which a dual mode of a child mode and an adult mode is provided.
Another object of the present specification is to provide a mobile device and a method for controlling the same, in which different lock states of a first lock state and a second lock state are provided, and different unlock interfaces are provided depending on the lock state.
Still another object of the present specification is to provide a mobile device and a method for controlling the same, in which an enter mode (child mode or adult mode) after a lock state is unlocked is varied depending on a first unlock interface unlocking a first lock state and a second unlock interface unlocking a second lock state.
Further still another object of the present specification is to provide a mobile device and a method for controlling the same, in which an adult mode is implemented to process an event for the adult mode when the event for the adult mode occurs while the mobile device is being used in a child mode.
Further still another object of the present specification is to provide a mobile device and a method for controlling the same, in which an application implemented in a child mode and an application implemented in an adult mode are provided separately and detailed configuration of an application may be set in a corresponding mode which is being implemented.
Additional advantages, objects, and features of the specification will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the specification. The objectives and other advantages of the specification may be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.
To achieve these objects and other advantages and in accordance with the purpose of the specification, as embodied and broadly described herein, a mobile device providing a dual mode of a child mode and an adult mode comprises a display unit configured to display at least one application implemented in the child mode and the adult mode; a sensor unit configured to sense a user input for the mobile device and transferring a signal based on the sensed result to a processor; and the processor configured to control the display unit and the sensor unit, wherein the processor further configured to: provide a first unlock interface to unlock a first lock state, wherein the first unlock interface allows the mobile device to enter into the child mode or the adult mode after unlocking the first lock state, display at least one application implemented in the child mode if it enters into the child mode through the first unlock interface, enter a second lock state when an event for the adult mode is detected, and provide a second unlock interface to unlock the second lock state, wherein the second unlock interface allows the mobile device to enter into the adult mode only after unlocking the second lock state.
A method for controlling a mobile device, which provides a dual mode of a child mode and an adult mode, comprises providing a first unlock interface to unlock a first lock state, wherein the first unlock interface allows the mobile device to enter into the child mode or the adult mode after unlocking the first lock state; displaying at least one application implemented in the child mode when the mobile device enters into the child mode through the first unlock interface; detecting an event for the adult mode in the child mode; entering a second lock state; and providing a second unlock interface to unlock the second lock state, wherein the second unlock interface allows the mobile device to enter into the adult mode only after unlocking the second lock state.
According to the one embodiment, the mobile device may provide a dual mode of a child mode and an adult mode so as to provide a user with different applications and different functions per mode. As a result, the user may use a function of a normal mobile device in an adult mode as it is and may limit the function of the mobile device to play of a child in a child mode. Accordingly, the user of the mobile device may prevent the child from changing configuration of the mobile device.
Also, according to another embodiment, the mobile device may provide lock states (first lock state and second lock state) separately and provide different unlock interfaces performing unlocking in accordance with the lock state. Accordingly, the mobile device may set different lock states as the case may be, thereby restricting a mode which the user enters.
Also, according to still another embodiment, if the mobile device of the child mode detects an event of an adult mode, the user may prevent the child from processing the event by setting the second lock state allowing entrance to the adult mode only.
Also, according to further still another embodiment, the mobile device may separately provide an application implemented in a child mode and an application implemented in an adult mode, whereby the adult may set the application that may be used by the child.
Finally, according to further still another embodiment, the mobile device may allow detailed configuration of an application to be set in a corresponding mode which is being implemented, whereby the child may set the configuration of the application implemented in the child mode. Accordingly, the child may feel that he/she plays his/her own mobile device.
More detailed advantageous effects will be described hereinafter.
It is to be understood that both the foregoing general description and the following detailed description of the present specification are exemplary and explanatory and are intended to provide further explanation of the specification as claimed.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings, which are included to provide a further understanding of the specification and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the specification and together with the description serve to explain the principle of the specification. In the drawings:
FIG. 1 is a block diagram illustrating a function of a mobile device in accordance with one embodiment;
FIG. 2 is a diagram illustrating embodiments of a first unlock interface for unlocking a first lock state;
FIG. 3 is a diagram illustrating that a mobile device of a first lock state enters into a child mode through a first unlock signal for a first unlock interface in accordance with one embodiment;
FIG. 4 is a diagram illustrating that a mobile device of a first lock state enters into an adult mode through a second unlock signal for a first unlock interface in accordance with one embodiment;
FIG. 5 is a diagram illustrating that an event for an adult mode occurs in a mobile device of a child mode in accordance with one embodiment;
FIG. 6 is a diagram illustrating that a mobile device of a second lock state is unlocked by a second unlock interface in accordance with one embodiment;
FIG. 7 is a diagram illustrating that a mobile device of a second lock state is unlocked by a second unlock interface in accordance with another embodiment;
FIG. 8 is a diagram illustrating that a mobile device of a second lock state is unlocked by a second unlock interface in accordance with other embodiment;
FIG. 9 is a diagram illustrating that a mobile device of a second lock state provides information guiding mode switching in accordance with one embodiment;
FIG. 10 is a diagram illustrating a first setup interface for an application provided by a mobile device in accordance with one embodiment;
FIG. 11 is a diagram illustrating a second setup interface for an application provided by a mobile device in accordance with one embodiment;
FIG. 12 is a block diagram illustrating that mode switching is performed between a child mode and an adult mode in a mobile device in accordance with one embodiment;
FIG. 13 is a flow chart illustrating a method for controlling a mobile device in accordance with one embodiment;
FIG. 14 is a flow chart illustrating a method for controlling a mobile device in accordance with another embodiment;
FIG. 15 is a flow chart illustrating a method for controlling a mobile device in accordance with still another embodiment;
FIG. 16 is a flow chart illustrating a method for controlling a mobile device in accordance with further still another embodiment; and
FIG. 17 is a flow chart illustrating a method for controlling a mobile device in accordance with further still another embodiment.
DETAILED DESCRIPTION OF THE INVENTION
Reference will now be made in detail to the preferred embodiments of the present specification, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts. The embodiments of the present specification shown in the accompanying drawings and described by the drawings are only exemplary, and technical spirits of the present specification and its main operation are not limited by such embodiments.
Although the terms used in the present specification are selected from generally known and used terms considering their functions in the present specification, the terms can be modified depending on intention of a person skilled in the art, practices, or the advent of new technology. Also, in special case, the terms mentioned in the description of the present specification may be selected by the applicant at his or her discretion, the detailed meanings of which are described in relevant parts of the description herein. Accordingly, the terms used herein should be understood not simply by the actual terms used but by the meaning lying within and the description disclosed herein.
Although the embodiments will be described in detail with reference to the accompanying drawings and the disclosure described by the drawings, it is to be understood that the present specification is not limited by such embodiments.
FIG. 1 is a block diagram illustrating a function of a mobile device in accordance with one embodiment. FIG. 1 is only exemplary and some modules may be deleted or new modules may be additionally provided in accordance with the need of the person with ordinary skill in the art.
As shown in FIG. 1 , a mobile device 100 according to one embodiment may include a display unit 110 , a sensor unit 120 , a storage unit 130 , a communication unit 140 , and a processor 150 .
The display unit 110 outputs image data on a display screen. The display unit 110 may output an image on the basis of contents or applications implemented by the processor 150 or a control command of the processor 150 .
Also, the mobile device 100 according to one embodiment may provide a dual mode of a child mode and an adult mode. Accordingly, the display unit 110 may display at least one application implemented in the child mode and the adult mode. For example, the display unit 110 may display an icon corresponding to at least one application implemented in the child mode and the adult mode.
The sensor unit 120 may sense a peripheral environment of the mobile device 100 by using at least one sensor provided in the mobile device 100 and transfer the sensed result to the processor 150 in the form of a signal. Also, the sensor unit 120 may sense an input of a user and transfer an input signal based on the sensed result to the processor 150 .
Accordingly, the sensor unit 120 may include at least one sensing means. According to one embodiment, the at least one sensing means may include a gravity sensor, a terrestrial magnetism sensor, a motion sensor, a gyroscope sensor, an acceleration sensor, an infrared sensor, an inclination sensor, a brightness sensor, an altitude sensor, a smell sensor, a temperature sensor, a depth sensor, a pressure sensor, a bending sensor, an audio sensor, a global positioning system (GPS) sensor, and a touch sensor.
Also, the sensor unit 120 refers to the aforementioned various sensing means, and may sense various inputs of the user and environment of the mobile device 100 and transfer the sensed result to the processor 150 , whereby the processor 150 may perform the operation based on the sensed result. The aforementioned sensors may be included in the mobile device 100 as separate elements or may be incorporated into at least one element.
Also, if the display unit 110 includes a touch sensitive display, it may sense a user input such as a touch input.
Accordingly, the processor 150 may generate a control signal by using an input signal based on the user input through the sensor unit 120 or the display unit 110 and control the mobile device 100 by using the control signal.
In other words, the processor 150 may receive the user input through the sensor unit 120 or the display unit 110 as the input signal and generate the control signal by using the input signal. For example, the control signal may include a signal (hereinafter, referred to as ‘unlock signal’) for unlocking the lock state of the mobile device 100 .
Also, the processor 150 may control the units included in the mobile device 100 in accordance with the control signal.
Hereinafter, if each step or operation performed by the mobile device starts is performed through the user input, it is to be understood that the procedure of generating the input signal and the control signal in accordance with the user input is included in the aforementioned description.
Also, it may be expressed that the processor controls the mobile device or the units included in the mobile device in accordance with the user input. The processor may be described to mean the mobile device.
The storage unit 130 may store various digital data such as audio, photos, moving pictures, and applications. The storage unit 130 refers to various digital data storage areas, such as a flash memory, a random access memory (RAM), and a solid state drive (SSD).
Also, the storage unit 130 may temporarily store data received from an external device through the communication unit 140 . At this time, the storage unit 130 may be used for buffering for outputting the data, which are received from the external device, from the mobile device 100 . In this case, the storage unit 130 may selectively be provided on the mobile device 100 .
Also, the storage unit 130 may store information on at least one application implemented in a child mode and at least one application implemented in an adult mode.
The communication unit 140 may transmit and receive data to and from the external device by performing communication with the external device by using various protocols. Also, the communication unit 140 may transmit and receive digital data such as contents and applications to and from an external network by accessing the external network through wire or wireless.
In addition, although not shown in FIG. 1 , the mobile device may include audio input and output units or a power unit.
The audio output unit (not shown) includes an audio output means such as a speaker and earphone. Also, the audio output unit may output voice on the basis of contents implemented in the processor 150 or the control command of the processor 150 . At this time, the audio output unit may selectively be provided on the mobile device 100 .
The power unit is a power source connected with a battery inside the device or an external power, and may supply the power to the mobile device 100 .
Also, the mobile device 100 is shown in FIG. 1 as a block diagram. In FIG. 1 , respective blocks are shown to logically identify the elements of the device. Accordingly, the aforementioned elements of the device may be provided as one chip or a plurality of chips in accordance with design of the device.
In the meantime, the mobile device according to one embodiment may provide a dual mode of a child mode and an adult mode. To this end, the mobile device according to one embodiment may provide two lock states of a first lock state and a second lock state, and may provide a first unlock interface for unlocking the first lock state and a second unlock interface for unlocking the second lock state. Hereinafter, a description as to a lock state set in accordance with a dual mode and when the lock state is set will be made, and a mode provided when the lock state is unlocked in accordance with the first unlock interface and the second unlock interface will be described.
First of all, the mobile device according to one embodiment may provide the first unlock interface that unlocks the first lock state. The first lock state is the state that input of the user or occurrence of an event is on standby. Accordingly, if the mobile device enters the first lock state, it may make a screen become an off state in the form of a dark screen until it detects the input of the user or occurrence of an event.
In other words, in order to reduce unnecessary power consumption, the mobile device may enter the first lock state if a previously set time passes without input of the user or occurrence of an event. At this time, the mobile device may enter the first lock state in a child mode or an adult mode. In other words, the mode for entering the first lock state is not limited to a specific mode, and the child mode and the adult mode may be the mode for entering the first lock state.
The mobile device of the first lock state is on standby for input of the user or occurrence of an event. If the mobile device detects the input of the user or occurrence of an event, it may provide the first unlock interface for unlocking the first lock state.
The first unlock interface is an unlock interface provided if the mobile device of the first lock state detects the input of the user or occurrence of an event. Also, the first unlock interface may unlock the first lock state and allow entrance to the child mode or adult mode.
In other words, the mobile device may unlock the first lock state and enter into the child mode or adult mode in accordance with the input signal of the user for the first unlock interface. To this end, the first unlock interface may allow a first unlock signal for entrance to the child mode and a second unlock signal for entrance to the adult mode.
If the mobile device detects the input signal for the first unlock interface, which is input by the user, it may determine whether the input signal is the first unlock signal for entrance to the child mode or the second unlock signal for entrance to the adult mode, and may enter into the child mode or the adult mode.
FIG. 2 is a diagram illustrating embodiments of a first unlock interface for unlocking a first lock state.
The mobile device may enter into the child mode or the adult mode by receiving an unlock signal from the user through the first unlock interface. The unlock signal may be the signal generated if the user performs a touch input in accordance with a pattern which is previously set, as shown in (a) of FIG. 2 . Also, the unlock signal may be the signal generated if the user inputs a series of numbers which are previously set, as shown in (b) of FIG. 2 . Also, the unlock signal may be the signal generated if a fingerprint of the user is input as shown in (c) of FIG. 2 . At this time, the mobile device may further include a unit for fingerprint input to receive the fingerprint of the user.
As described above, the unlock signal is intended to unlock the lock state of the mobile device, and may have various types such as text, number, touch pattern, and fingerprint. The unlock signal is not limited to a specific type. However, the mobile device may sense touch and hovering of the user for the screen, and may also sense a motion of the user based on the mobile device through a gyroscope sensor and recognize a voice. Accordingly, the unlock signal may be generated by at least one of touch, hovering, fingerprint, motion and voice of the user.
Also, as shown in (a) to (c) of FIG. 2 , even though the first unlock interface receives different types of unlock signals, it receives the first unlock signal for entering into the child mode separately from the second unlock signal for entering into the adult mode. In other words, if the mobile device detects the first unlock signal for the first unlock interface, it may provide an environment based on the child mode after unlocking the lock state. If the mobile device detects the second unlock signal, it may provide an environment based on the adult mode after unlocking the lock state.
In this respect, the unlock signal will be described as an example of the signal generated when the user performs a touch input in accordance with a pattern which is previously set, as shown in (a) of FIG. 2 .
FIG. 3 is a diagram illustrating that a mobile device of a first lock state enters into a child mode through a first unlock signal for a first unlock interface in accordance with one embodiment.
Since the child mode means that the user is a child, as shown in (a) of FIG. 3 , the mobile device 300 may set a first unlock signal in accordance with a pattern 310 which is easy for children to remember or input. The mobile device 300 may basically provide the pattern 310 for the first unlock signal, and the user may previously set the pattern 310 for the first unlock signal through the mobile device 300 .
If the mobile device 300 detects the first unlock signal, it may provide a user interface 320 implemented in the child mode as shown in (b) of FIG. 3 . The user interface 320 may include at least one application implemented in the child mode.
As described above, if the mobile device 300 enters into the child mode, among at least one application installed in the mobile device 300 , the application set to be performed in the child mode may only be displayed. The application which is not allowed to be used in the child mode cannot be displayed. This will be described in detail with reference to FIG. 10 .
FIG. 4 is a diagram illustrating that a mobile device of a first lock state enters into an adult mode through a second unlock signal for a first unlock interface in accordance with one embodiment.
Since the adult mode means that the user is an adult, as shown in (a) of FIG. 4 , the mobile device 400 may set a second unlock signal in accordance with a complicated pattern 410 which is difficult for children to unlock the lock state.
The mobile device 400 according to one embodiment may set a first unlock signal for entering into the child mode differently from a second unlock signal for entering into the adult mode. As a result, it is advantageous in that data of the mobile device may be prevented from being deleted due to mistake or error manipulation of the child and contents harmful to children may be blocked. Accordingly, if the pattern for the second unlock signal is the pattern which is difficult for the child to remember, the above advantages may be more increased.
Also, the mobile device 400 may basically provide the pattern 410 for the second unlock signal, and the user may previously set the pattern 410 for the second unlock signal through the mobile device 400 .
If the mobile device 400 detects the second unlock signal, it may provide a user interface 420 implemented in the adult mode as shown in (b) of FIG. 4 . The user interface 420 may include at least one application implemented in the adult mode.
If necessary, the user interface implemented in the adult mode may display all the applications installed in the mobile device 400 . The user of the adult mode may identify the application implemented in the child mode by allowing the user of the adult mode to view the application implemented in the child mode, and may set the mode where the application is implemented. This will be described in more detail with reference to FIG. 10 .
In the meantime, the mobile device may provide a call transmission and reception function, a message transmission and reception function and an e-mail transmission and reception function. At this time, if the child of the user receives a call or text message related to business of the user with using the mobile device of the user, a problem may occur in business of the user. Accordingly, the mobile device according to one embodiment may allow the above functions to be used in the adult mode only.
However, in case of a function in which event processing is important at the time when an event occurs, such as the function for call reception, the mobile device may allow the user to enter into the adult mode and process the corresponding event by notifying the user that the event has occurred even though it restricts event processing in the child mode. As a result, the mobile device according to one embodiment may allow the user to immediately process an event regarded by the user to be important or an event of which processing is important at the time when the event occurs. This will be described with reference to FIG. 5 and FIG. 6 .
FIG. 5 is a diagram illustrating that an event for an adult mode occurs in a mobile device of a child mode in accordance with one embodiment. It is assumed that the mobile device detects the first unlock signal for the first unlock interface unlocking the first lock state and enters into the child mode.
(a) of FIG. 5 illustrates that the mobile device of the child mode displays an implementation screen of a specific application 510 implemented in the child mode. When the mobile device of the child mode implements the specific application 510 , it may detect an event for the adult mode.
The event means occurrence of an operation or work that affects implementation of an application or task of the mobile device, and may occur when an operation or work generated by the user occurs or data are received from an external device. For example, the mobile device may detect occurrence of the event if it receives a call, text message or e-mail.
However, if the mobile device is allowed to process such an event even in the child mode, a problem may occur in that the user of the mobile device may miss an important call or message due to the child. Accordingly, the mobile device may be set such that event processing cannot be processed in the child mode. In other words, the mobile device may process an event in the adult mode only. However, the mobile device of the child mode may detect occurrence of the event even though it cannot process the event. Accordingly, if the mobile device of the child mode detects occurrence of the event, it may enter into the adult mode to process the event.
If the mobile device detects an event for the adult mode in the child mode, as shown in (b) of FIG. 5 , it may enter a second lock state and display a second unlock interface 520 that unlocks the mobile device of the second lock state. At this time, the second unlock interface 520 may display information 521 related to the detected event.
The second lock state is on standby for input of the user. If the mobile device detects the event for the adult mode in the child mode, it may enter the second lock state. Also, the mobile device may enter the second lock state and at the same time may display the second unlock interface that unlocks the second lock state.
Hereinafter, the first lock state and the second lock state, and the first unlock interface and the second unlock interface will be described in more detail.
First of all, the mobile device may enter the first lock state in the child mode or adult mode. In other words, the mobile device may enter the first lock state regardless of the fact that the current mode is the child mode or the adult mode if there is no input of the user or occurrence of an event until a previously set time passes.
On the other hand, the mobile device may enter the second lock state in the child mode only. In other words, the mobile device may enter the second lock state only if it detects the event for the adult mode in the current child mode.
Also, the mobile device that has entered the first lock state is on standby for input of the user or occurrence of the event. Accordingly, the mobile device that has entered the first lock state may provide the first unlock interface for unlocking the first lock state if it detect the input of the user or occurrence of the event.
On the other hand, the mobile device that has entered the second lock state is in the state that it detects the event for the adult mode. Accordingly, the mobile device may enter the second lock state and at the same time provide the second unlock interface for unlocking the second lock state.
In other words, the first unlock interface is provided if the input of the user or occurrence of the event is detected in the first lock state, whereas the second unlock interface may be provided at the same time when the mobile device enters the second lock state.
Also, the first unlock interface may allow both the first unlock signal for entering into the child mode and the second unlock signal for entering into the adult mode. However, the second unlock interface may allow only the second unlock signal for entering into the adult mode. This is because that the mobile device should enter into the adult mode to allow the user to process the event as the mobile device of the child mode detects the event for the adult mode. Accordingly, the second unlock interface may entrance to the adult mode only after unlocking the lock state.
Also, the second unlock interface is different from the first unlock interface, which receives the unlock signal only, in that it includes information on the event.
(b) of FIG. 5 illustrates that information 521 on an event includes caller information and caller number together with a call icon for notifying occurrence of an event for call reception. For example, if the mobile device detects an event for message reception, information related to the event may include at least one of message sender information, message sender number and message together with a message icon for notifying occurrence of the event for message reception. In other words, the information on the event may include information that may allow the user to identify the event, for example, information as to what the generated event is.
FIG. 6 is a diagram illustrating that a mobile device of a second lock state is unlocked by a second unlock interface in accordance with one embodiment. In the same manner as FIG. 5 , it is assumed that the mobile device of the child mode enters the second lock state by detecting the event for the adult mode and provides the second unlock interface.
As shown in (a) of FIG. 6 , the mobile device may detect a second unlock signal 611 for the second unlock interface 610 . The mobile device that has detected the second unlock signal 611 may unlock the second lock state and enter into the adult mode.
Also, the mobile device that has unlocked the second lock state through the second unlock interface 610 and entered into the adult mode may process the detected event. If the event detected by the mobile device is the event for call reception, as shown in (b) of FIG. 6 , the mobile device may receive a call.
At this time, the mobile device may enter into the adult mode and at the same time process the event for call reception even though there is no separate input of the user. Even though the user does not perform a touch or input for a call, the operation of entrance to the adult mode through the second unlock interface 610 may be regarded as that for call reception. If the mobile device receives an input signal of the user, which is for event processing, after entering into the adult mode, it may process the detected event.
However, in the same manner as that a call ends, the mobile device that has completely processed the detected event may enter the first lock state as shown in (c) of FIG. 6 , and may provide the first unlock interface 620 for unlocking the first lock state. As described above, the first unlock interface 620 may allow the first unlock signal for entering into the child mode and the second unlock signal for entering into the adult mode.
Accordingly, if the user intends to perform additional task in the adult mode, the user may unlock the first lock state by inputting the second unlock signal and enter into the adult mode. On the other hand, if the user desires to enter into the child mode to allow the child to use the mobile device, the user may unlock the first lock state by inputting the first unlock signal and enter into the child mode.
As described above, if the detected event is completely processed, the mobile device may enter the first lock state and provide the first unlock interface, whereby the user may enter into a desired mode to perform a desired task.
However, after the detected event is completely processed, it may be more preferable for the user that the mobile device continues to implement the application implemented in the child mode. Also, it may be more preferable that the mobile device maintains the adult mode to allow the user to perform additional task after the detected event is completely processed. This will be described in more detail with reference to FIG. 7 and FIG. 8 .
First of all, FIG. 7 is a diagram illustrating that a mobile device of a second lock state is unlocked by a second unlock interface in accordance with another embodiment. In the same manner as FIG. 5 , it is assumed that the mobile device of the child mode enters the second lock state by detecting the event for the adult mode and provides the second unlock interface.
As shown in (a) of FIG. 7 , the mobile device may detect a second unlock signal 711 for a second unlock interface 710 . The mobile device that has detected the second unlock signal 711 may unlock the second lock state and enter into the adult mode.
Also, the mobile device that has entered into the adult mode may process the detected event. (b) of FIG. 7 illustrates an event for call reception as an example of the detected event. As described above, the mobile device may process the event simultaneously with unlocking the second lock state or may process the event if there is a request of the user after unlocking the second lock state.
At this time, if the detected event is completely processed, the mobile device may automatically be switched from the adult mode to the child mode. As a result, as shown in (c) of FIG. 7 , the mobile device may continue to implement the application 720 implemented at the time when detecting the event.
Also, in a state that the mobile device displays the first unlock interface after entering the first lock state as shown in (c) of FIG. 6 , if the user enters into the child mode through the first unlock signal, the mobile device may continue to implement the application implemented at the time when detecting the event.
However, as shown in (c) of FIG. 7 , if the mobile device continues to implement the application which is being implemented, without entering the lock state, the user does not need to unlock the lock state, whereby convenience is improved. This is because that the adult has only to pass the mobile device to the child.
FIG. 8 is a diagram illustrating that a mobile device of a second lock state is unlocked by a second unlock interface in accordance with other embodiment. In the same manner as FIG. 5 , it is assumed that the mobile device of the child mode enters the second lock state by detecting the event for the adult mode and provides the second unlock interface. Also, since (a) of FIG. 8 and (b) of FIG. 8 are the same as (a) of FIG. 6 and (b) of FIG. 6 and (a) of FIG. 7 and (b) of FIG. 7 , their detailed description will be omitted.
As shown in (a) of FIG. 8 , if the mobile device detects a second unlock signal for a second unlock interface, it may unlock the second lock state and enter into the adult mode. Also, as shown in (b) of FIG. 8 , the mobile device that has entered into the adult mode may process the detected event.
At this time, if the detected event is completely processed, the mobile device may provide a basic home screen 810 provided in the adult mode as shown in (c) of FIG. 8 . The basic home screen may include an icon corresponding to at least one application implemented in the adult mode.
If the event for the adult mode occurs in the mobile device of the child mode, a task related to the event may be performed even after the event is completed. For example, the user who has ended a call may make an important note or should write and send a mail in respect of the call message. Accordingly, the mobile device according to one embodiment may allow the user to continue to perform a necessary task by maintaining the adult mode after processing the event.
Also, although the mobile device may continue to maintain the adult mode, it may maintain the adult mode for a previously set time after the event is completely processed and may switch the adult mode to the child mode after the previously set time is exceeded. For example, the mobile device may automatically switch the adult mode to the child mode if the previously set time is exceeded without input of the user or occurrence of the event after processing the event.
As described above, the mobile device may perform the task related to the event by maintaining the adult mode for a given time. Afterwards, the mobile device may return to the child mode to continue to implement the application implemented in the child mode, whereby user convenience may be increased.
In the meantime, as shown in (a) of FIG. 6 , (a) of FIG. 7 and (a) of FIG. 8 , if the mobile device of the child mode may enter the second lock state by detecting the event for the adult mode and displays the second unlock interface, it may disable the function for processing the event in the child mode.
For example, the mobile device that has received a call, that is, the mobile device that has detected the event for call reception may press a previously set button or reject a received call by touching a menu button on the screen. Alternatively, the mobile device that has detected the event for message reception, the event for mail reception, etc. may turn off an alarm function even though the user does not check the message or mail.
As described above, the rejection of the received call or turn-off of the alarm function for message reception or mail reception may be regarded as event processing. However, if the function for processing the event is able to be performed in the child mode, the user may miss the important event processing due to the child. Accordingly, the mobile device according to one embodiment of the present specification may disable the function for processing the event in the child mode by detecting the event for the adult mode in the child mode.
As described above, if the mobile device of the child mode detects the event for the adult mode, it may disable the function for processing the event in the child mode. Alternatively, if the mobile device of the child mode detects the event for the adult mode, since it enters the second lock state and displays the second unlock interface, it may disable the function for processing the event at the second lock state. Accordingly, the child may be prevented from rejecting the received call or the user may be prevented from missing the important call or message due to turn-off of the message alarm function.
FIG. 9 is a diagram illustrating that a mobile device of a second lock state provides information guiding mode switching in accordance with one embodiment.
As shown in (a) of FIG. 9 , if the mobile device of the child mode detects the event for the adult mode, it may enter the second lock state and provide a second unlock interface 910 . The second unlock interface 910 may include information 911 related to the detected event. Also, the second unlock interface 910 may allow only a second unlock signal for entering into the adult mode. In other words, the second unlock interface 910 does not allow the first unlock signal for entering into the child mode.
However, as shown in (a) of FIG. 9 , the mobile device may detect the first unlock signal 913 for entering into the child mode, with respect to the second unlock interface 910 . This is because that the child who is using the mobile device in the child mode may input the first unlock signal 913 to enter into the child mode from the lock state. Accordingly, the mobile device may provide information 920 that guides mode switching from the child mode to the adult mode.
The information 920 guiding mode switching from the child mode to the adult mode may be displayed as a graphic image as shown in (b) of FIG. 9 . However, the information guiding mode switching is not limited to the graphic image and may also be provided as a voice guide message.
In the meantime, at least one application provided in the mobile device according to one embodiment may include at least one application implemented in the child mode only, at least one application implemented in the adult mode only, and at least one application implemented in the child mode and the adult mode. Accordingly, the mobile device according to one embodiment may provide a first setup interface that configures a mode for implementing the provided application.
FIG. 10 is a diagram illustrating a first setup interface for an application provided by a mobile device in accordance with one embodiment.
As shown in FIG. 10 , the first setup interface may include an application interface 1010 displaying at least one application provided in the mobile device, an adult application interface 1020 displaying at least one application which will be implemented in the adult mode, and a child application interface 1030 displaying at least one application which will be implemented in the child mode.
The first setup interface may provide an environment where the user may shift an icon corresponding to the application included in the application interface 1010 to the adult application interface 1020 and the child application interface 1030 through an input method such as a touch.
At this time, the application included in the application interface 1010 may be shifted to the adult application interface 1020 and the child application interface 1030 . In this case, the corresponding application may be implemented in both the adult mode and the child mode. In other words, the application may be implemented in the child mode only, or the adult mode only, and may be implemented in both the child mode and the adult mode in accordance with configuration.
Also, the first setup interface may be provided in the adult mode. This is because that it is not reasonable to allow the child, who is the user of the child mode, to determine an application and a mode to be implemented.
However, in case of the application which will be implemented in the child mode, the main user of the corresponding application is the child. Accordingly, the mobile device may provide a second setup interface, which configures an environment for implementing at least one application in the child mode, in the child mode.
FIG. 11 is a diagram illustrating a second setup interface for an application provided by a mobile device in accordance with one embodiment.
The second setup interface 1110 may configure an environment for implementing at least one application in the child mode. The environment may include all the items that may be configured by the user when the user implements the application, such as the time when the application is implemented, sound control when the application is implemented, and brightness control when the application is implemented.
Also, the second setup interface 1110 may provide a user interface (UI) that may easily configure the environment of the application to be implemented in the child mode. Accordingly, even in case of the same application, if the environment is configured in the child mode, a user interface different from the user interface provided in the adult mode may be provided to be acquainted with the child.
FIG. 12 is a block diagram illustrating that mode switching is performed between a child mode and an adult mode in a mobile device in accordance with one embodiment. Hereinafter, the mode switching procedure between the child mode and the adult mode will be described together with the first lock state and the second lock state.
If the mobile device is powered on, it may enter the first lock state 1210 . The first lock state 1210 is the state that input of the user or occurrence of the event is on standby. The mobile device may configure the first lock state 1210 in case of the power-on state, and may provide the first unlock interface for unlocking the first lock state 1210 to allow the user to use the mobile device.
The mobile device of the first lock state 1210 may enter into the child mode 1220 or the adult mode 1260 in accordance with the unlock signal detected through the first unlock interface. The unlock signal may be configured previously, and may be varied after being configured.
In other words, if the mobile device of the first lock state 1210 detects the first unlock signal, it may enter into the child mode 1220 . If the mobile device of the first lock state 1210 detects the second unlock signal, it may enter into the adult mode 1260 .
In the meantime, after the mobile device of the first lock state 1210 enters into the child mode 1220 or the adult mode 1260 , if there is no input of the user or occurrence of the event for a previously set time, or in accordance with the request of the user, the mobile device may enter the first lock state 1210 . In this way, as the mobile device enters the first lock state from the child mode or the adult mode, it may reduce unnecessary power consumption, especially reduce unnecessary and frequent reaction of a touch sensor display.
Also, if the mobile device of the child mode 1220 detects the event for the adult mode, it may enter the second lock state 1230 . The second lock state 1230 is the state that the input of the user is on standby. The mobile device may prepare entrance to the adult mode by entering the second lock state 1230 to process the detected event. In other words, if the mobile device detects the event for the adult mode, it may provide the second lock state and the second unlock interface to allow the user to input the second unlock signal for entering into the adult mode.
If the mobile device of the second lock state 1230 detects the second unlock signal for entering into the adult mode in accordance with the input of the user, it may enter into the adult mode to process the detect event ( 1240 ). At this time, the adult mode may be the same mode as the adult mode 1260 entering at the first lock state, and for convenience of description, these adult modes are shown at different blocks. However, the mobile device that has completely processed the event ( 1240 ) may enter the first lock state 1210 , and may enter into the adult mode or the child mode in accordance with the configuration. This will be described in more detail with reference to FIG. 13 to FIG. 15 .
In the meantime, if the mobile device of the second lock state 1230 detects the first unlock signal for entering into the child mode, in accordance with the input of the user, it may send an error report 1250 and maintain the second lock state 1230 .
The second lock state 1230 may allow the entrance to the adult mode only unlike the first lock state that allows the entrance to the child mode and the adult mode. This is intended to process the event for the adult mode. Accordingly, if the mobile device receives the first unlock signal for entering into the child mode, it may send the error report 1250 to allow the user to input the second unlock signal for entering into the adult mode. At this time, the error report 1250 may include information guiding mode switching.
In the meantime, FIG. 13 is a flow chart illustrating a method for controlling a mobile device in accordance with one embodiment.
As described with reference to FIG. 2 to FIG. 4 , the mobile device may provide the first unlock interface that unlocks the first lock state (S 1300 ). Also, as described with reference to FIG. 3 , if the mobile device enters into the child mode through the first unlock interface, it may display at least one application implemented in the child mode.
At this time, as described with reference to FIG. 5 , the mobile device may detect the event for the adult mode (S 1320 ). The event means occurrence of operation or work that affects implementation of the application or task. The event may occur when the operation or work generated by the user occurs or data are received from the external device.
As described with reference to FIG. 6 to FIG. 8 , the mobile device that has detected the event may enter the second lock state (S 1330 ), and may provide the second unlock interface that unlocks the second lock state (S 1340 ). The second unlock interface may allow the entrance to the adult mode only. Accordingly, the mobile device may enter into the adult mode and process the detected event only if the user enters the second unlock signal for entering into the adult mode.
After the mobile device processes the detected event, it may enter into the child mode again and maintain the adult mode. Also, the mobile device may enter the first lock state and enter into the child mode or the adult mode in accordance with the unlock signal input by the user. In other words, the mode or lock state entering after the mobile device processes the detected event may be varied depending on the configuration. This will be described in detail with reference to FIG. 14 to FIG. 16 .
FIG. 14 is a flow chart illustrating a method for controlling a mobile device in accordance with another embodiment.
As described with reference to FIG. 5 , the mobile device may detect the event for the adult mode while a specific application is being implemented in the child mode (S 1400 ). The mobile device that has detected the event may enter the second lock state (S 1410 ), and may provide the second unlock interface that unlocks the second lock state (S 1420 ). The mobile device may enter the second lock state and provide the second unlock interface at the same time.
As described with reference to FIG. 6 to FIG. 8 , the mobile device may detect whether the signal input by the user through the second unlock interface is the first unlock signal for entering into the child mode or the second unlock signal for entering into the adult mode (S 1430 ).
The second unlock interface allows the entrance to the adult mode only. Accordingly, if the signal detected by the mobile device is the first unlock signal for entering into the child mode, the mobile device may disable the function for processing the detected event (S 1440 ). This is intended to block event processing to prevent the event for the adult mode from being rejected to be processed or being processed in the child mode. Also, as described with reference to FIG. 9 , the mobile device may provide information that guides mode switching (S 1450 ).
Also, the mobile device may disable the function for processing the detected event in the child mode, if it detects the event, regardless of the detected signal of the first unlock signal or the second unlock signal.
In the meantime, if the signal detected by the mobile device is the second unlock signal for entering into the adult mode, the mobile device may process the event after entering into the adult mode (S 1460 ).
At this time, if the mobile device detects the second unlock signal, it may enter into the adult mode and at the same time process the event. For example, if the event is the event for call reception, the mobile device may enter into the adult mode and at the same time connect a call. If the event is the event for message reception, the mobile device may enter into the adult mode and at the same time display the received message.
As described with reference to FIG. 6 , the mobile device may enter the first lock state after completely processing the event (S 1470 ). The mobile device may provide the user with an opportunity of selecting the adult mode or the child mode by entering the first lock state and displaying the first unlock interface.
The mobile device may detect whether the signal input by the user through the first unlock interface is the first unlock signal for entering into the child mode or the second unlock signal for entering into the adult mode (S 1480 ). The first unlock interface may allow both the entrance to the child mode and the entrance to the adult mode unlike the second unlock interface that allows the entrance to the adult mode only.
As described with reference to FIG. 3 , if the mobile device detects the first unlock signal, it may continue to implement the specific application which is being implemented in the child mode (S 1490 ). If the user inputs the first unlock signal, it means that the user intends to continue to perform the work, which is being implemented before the event occurs, by entering into the child mode. Accordingly, the mobile device may continue to implement the specific application, which is being implemented before the event occurs, by entering into the child mode, whereby convenience of the user may be improved.
Also, as described with reference to FIG. 4 , if the mobile device detects the second unlock signal, it may display at least one application implemented in the adult mode (S 1500 ).
FIG. 15 is a flow chart illustrating a method for controlling a mobile device in accordance with still another embodiment.
As described with reference to FIG. 5 , the mobile device may detect the event for the adult mode while a specific application is being implemented in the child mode (S 1510 ). The mobile device that has detected the event may enter the second lock state (S 1520 ), and may provide the second unlock interface that unlocks the second lock state (S 1530 ).
As described with reference to FIG. 6 to FIG. 8 , the mobile device may detect whether the signal input by the user through the second unlock interface is the first unlock signal for entering into the child mode or the second unlock signal for entering into the adult mode (S 1540 ).
The second unlock interface allows the entrance to the adult mode only. Accordingly, if the signal detected by the mobile device is the first unlock signal for entering into the child mode, the mobile device may disable the function for processing the detected event (S 1550 ). This is intended to block event processing to prevent the event for the adult mode from being rejected to be processed or being processed in the child mode. Also, as described with reference to FIG. 9 , the mobile device may provide information that guides mode switching (S 1560 ).
In the meantime, if the signal detected by the mobile device is the second unlock signal for entering into the adult mode, the mobile device may process the event after entering into the adult mode (S 1570 ).
As described with reference to FIG. 7 , the mobile device may enter into the child mode again after completely processing the event (S 1580 ). Also, the mobile device may continue to implement the specific application which is being implemented in the child mode (S 1590 ).
As described above, if the event is completely processed, the mobile device may automatically enter into the mode before the event occurs. Accordingly, since the user does not need to take any action for mode switching, the user may feel convenience.
FIG. 16 is a flow chart illustrating a method for controlling a mobile device in accordance with further still another embodiment.
As described with reference to FIG. 5 , the mobile device may detect the event for the adult mode while a specific application is being implemented in the child mode (S 1600 ). The mobile device that has detected the event may enter the second lock state (S 1610 ), and may provide the second unlock interface that unlocks the second lock state (S 1620 ).
As described with reference to FIG. 6 to FIG. 8 , the mobile device may detect whether the signal input by the user through the second unlock interface is the first unlock signal for entering into the child mode or the second unlock signal for entering into the adult mode (S 1630 ).
The second unlock interface allows the entrance to the adult mode only. Accordingly, if the signal detected by the mobile device is the first unlock signal for entering into the child mode, the mobile device may disable the function for processing the detected event (S 1640 ). This is intended to block event processing to prevent the event for the adult mode from being rejected to be processed or being processed in the child mode. Also, as described with reference to FIG. 9 , the mobile device may provide information guiding mode switching (S 1650 ).
In the meantime, if the signal detected by the mobile device is the second unlock signal for entering into the adult mode, the mobile device may process the event after entering into the adult mode (S 1660 ).
As described with reference to FIG. 8 , the mobile device that has completely processed the event may display at least one application implemented in the adult mode with maintaining the adult mode without performing separate mode switching (S 1670 ).
Generally, after the event occurs, it is likely that the user may perform additional work by using the mobile device. Accordingly, the mobile device may maintain the adult mode for a certain time period without mode switching after the event ends, whereby the user may use the mobile device conveniently.
Also, if a certain time period is exceeded, the mobile device may automatically enter into the child mode (S 1680 ) and continue to perform the work implemented in the child mode. In other words, if the mobile device detects the input of the user or occurrence of the event within a previously set time, it may continue to maintain the adult mode. However, if the mobile device fails to detect the input of the user or occurrence of the event within a previously set time, it may enter into the child mode.
FIG. 17 is a flow chart illustrating a method for controlling a mobile device in accordance with further still another embodiment.
As described with reference to FIG. 2 , the mobile device may provide the first unlock interface that unlocks the first lock state (S 1700 ). Also, as described with reference to FIG. 4 , if the mobile device enters into the adult mode through the first unlock interface, it may display at least one application implemented in the adult mode. Also, if the mobile device detects the event for the adult mode (S 1720 ), it may process the event.
In other words, the mobile device may enter the second lock state if it detects the event for the adult mode, whereas the mobile device may immediately process the event without mode switching or entering the lock state.
Also, characteristics operated when the mobile device of the child mode detects the event for the adult mode may be applied to even the case that the mobile device of the adult mode detects the event for the child mode.
Moreover, although the description may be made for each of the drawings, the embodiments of the respective drawings may be incorporated to achieve a new embodiment. A computer readable recording medium where a program for implementing the embodiments is recorded may be designed in accordance with the need of the person skilled in the art within the scope of the present specification.
Also, the mobile device and the method for controlling the same according to one embodiment are not limited to the aforementioned embodiments, and all or some of the aforementioned embodiments may selectively be configured in combination so that various modifications may be made in the aforementioned embodiments.
In the meantime, the method for controlling the mobile device may be implemented in a recording medium, which can be read by a processor provided in the network device, as a code that can be read by the processor. The recording medium that can be read by the processor includes all kinds of recording media in which data that can be read by the processor are stored. Examples of the recording medium include ROM, RAM, CD-ROM, magnetic tape, floppy disk, and optical data memory. Also, another example of the recording medium may be implemented in a type of carrier wave such as transmission through Internet. Also, the recording medium that can be read by the processor may be distributed in a computer system connected thereto through the network, whereby codes that can be read by the processor may be stored and implemented in a distributive mode.
It will be apparent to those skilled in the art that the present specification can be embodied in other specific forms without departing from the spirit and essential characteristics of the specification. Thus, the above embodiments are to be considered in all respects as illustrative and not restrictive. The scope of the specification should be determined by reasonable interpretation of the appended claims and all change which comes within the equivalent scope of the specification are included in the scope of the specification.
In this specification, both the product disclosure and the method disclosure have been described, and description of both may be made complementally if necessary. | A mobile device providing a dual mode of a first mode and a second mode, the mobile device comprising a display unit configured to display at least one application executable in the first mode and the second mode respectively a sensor unit configured to sense an input for the mobile device; and a processor configured to display the at least one application executable in the first mode when the mobile device enters into the first mode, detect an event for the at least one application being executed in the second mode when the mobile device is in the first mode, indicate information for the event, wherein the information only notifies an occurrence of the event, and restrict access to detailed information of the event when the mobile device is in the first mode, and display an interface to switch the first mode to the second mode. | 6 |
[0001] This application claims the benefit of the Korean Patent Application No. 10-2006-0003932, filed on Jan. 13, 2006, which is hereby incorporated in its entirety by reference as if fully set forth herein.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a laundry machine such as a washing machine or a clothes dryer, and more particularly, to a laundry machine having a wireless communicating controller therein. Although the present invention is suitable for a wide scope of applications, it is particularly suitable for configuring a controller with a main control unit and an input or display unit separated from the main control unit and performing wireless data communications between the main control unit and the input unit or the display unit.
[0004] 2. Discussion of the Related Art
[0005] Generally, a washing machine is a mechanical device that performs a washing cycle, a rinsing cycle, a dewatering cycle, and the like by rotating a drum or pulsator via a driving force of a motor. After laundry and water have been put into a drum, they are agitated to perform washing using the frictions between the laundry, water and drum.
[0006] Washing machines can be classified into a pulsator type washing machine, an agitator type washing machine, a drum type washing machine, and the like.
[0007] The drum type washing machine is a device that performs washing using a friction between a washing drum and laundry while a detergent, water and laundry are put into the washing drum. In this case, the washing drum is rotated by receiving a driving force of a driving part. Hence, the drum type washing machine is advantageous in causing less damage on the laundry, preventing the ravel of the laundry, and bringing washing effects of beating and rubbing.
[0008] FIG. 1 is a perspective diagram of a drum type washing machine according to a related art.
[0009] Referring to FIG. 1 , a controller 3 is provided to an upper part of a front side of a body of a drum type washing machine. In this case, the controller 3 includes function input keys for user's washing controls and a display unit displaying a remaining time and the like.
[0010] A plurality of buttons 31 , a display window 32 , an LED window 33 and a rotary knob 50 are provided to the controller 3 . Each of the buttons 31 and the rotary knob 50 are input tools to operate the washing machine. A user manipulates the buttons 31 and the knob 50 to input a specific washing course and time and the like in selecting a washing time, a washing type, a dewatering type, a drying type, etc.
[0011] The LED window 33 informs a user of various kinds of washing information such as a washing progress status, a remaining time and the like via flickering. And, the display window 32 informs a user of various kinds of washing information such as a washing progress status, a remaining time and the like via characters and symbols.
[0012] If a user selects the washing type or the like via the rotary knob 50 and/or the buttons 31 , a main control unit of the controller 3 controls washing associated information to be displayed on the LWD window 33 or the display window 32 and controls the washing machine to be operated according to the inputted information.
[0013] Meanwhile, a clothes dryer is a mechanical device that automatically dries wet clothes after completion of washing. And, like the drum type washing machine shown in FIG. 1 , a clothes dryer according to a related art is provided with a controller including an input means, a display means, a main control unit and the like.
[0014] Since the controller is provided to an upper part of a body of the related art washing machine or clothes dryer, if the washing machine or clothes dryer is installed at a high level far from a position where a user stands, the user has difficulty in accessing the controller. Hence, the user is inconvenient in using the controller. And, there is another inconvenience for a user to view a display unit by raising his head to observe a corresponding state displayed on the display unit
[0015] In case that the washing machine and the clothes dryer are arranged parallel to each other at a relatively lower place, the user will not have trouble using the controllers which are located to the upper part of the machines. However, if one of the washing machine and the clothes dryer is placed at a high place, for example on top of the other, the user is expected to have trouble using the controller of the one which is placed at a high place.
[0016] Besides, in the controller of the related art washing machine or clothes dryer, data communications between the main control unit and input unit or the display unit are carried out by wire communication. In the related art, communication lines are mandatory for the wire communication. And, the wire communication also makes the arrangement of the communication lines so complicated that the main control unit, the input unit, and the display unit are preferred to be put near one another.
[0017] With the wire communication, 29 electric wires are generally necessarily used for making electrical connections among them. It is very time-consuming to put the number of wires in electrical connection to the units.
[0018] After completion of connecting the electric wires to assemble the controller, it is very inconvenient to treat the controller, since the units of the controller need to be moved together. Sometimes, it is necessary to remove from the machine one unit of the controller. In this case, the wires cause inconvenience, too. In particular, in case that one unit of the controller needs to be moved, the inconvenience becomes worse. Moreover, if the input unit or the display unit moves to be placed in another position, the wire communication system is inappropriate.
[0019] Besides, since the washing machine or the clothes dryer is in a close relation to water, the electric wires within the machines should be treated to prevent short circuit by water.
SUMMARY OF THE INVENTION
[0020] Accordingly, the present invention is directed to a laundry machine having a wireless communicating controller therein that substantially obviates one or more problems due to limitations and disadvantages of the related art.
[0021] An object of the present invention is to provide a laundry machine having a wireless communicating controller therein, by which electric wires used for a controller in the washing machine are reduced and by which it is easy to separate and move an input unit or a display unit from a main control unit.
[0022] Another object of the present invention is to provide a washing machine having a wireless communicating controller therein, by which a mounting position of an input unit or a display unit can be easily changed.
[0023] Additional advantages, objects, and features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention. The objectives and other advantages of the invention may be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.
[0024] To achieve these objects and other advantages and in accordance with the purpose of the invention, as embodied and broadly described herein, a laundry machine according to the present invention includes a main control unit controlling an operation of the laundry machine and a user-interface unit having an input unit or a display unit. The input unit receives from a user an input of a command for an operation and the display unit displays information associated with the operation. The user-interface unit can be detached from the machine easily disconnected electrically from the main control unit. The user-interface unit wirelessly communicates data with the main control.
[0025] In a washing machine as an example for the laundry machine, a drum accommodating a laundry therein, a motor rotating the drum, a water supply valve adjusting a water supply of water, a drain pump for a water drain and the like are provided within a washing machine body. And, a controller includes a main control unit controlling the motor, the water supply valve, the drain pump and the like according to an installed washing course, an input unit receiving a user's selection of a washing course, and a display unit displaying information associated with the operation of the laundry machine to the user.
[0026] Preferably, the user-interface unit includes both of the input unit and the display unit.
[0027] More preferably, the display unit and the input unit are built in one body.
[0028] In this case, ‘the display unit and the input unit are built in one body’ means that the display unit and the input unit can be moved in one body but does not always mean that the display unit and the input unit are unified into one on a PCB or the like in detail configurations.
[0029] For instance, the display unit and the input unit are provided to a panel such as a housing that accommodates the respective detailed elements, thereby moving together.
[0030] Preferably, if possible, detailed elements of the display unit and the input unit are built in one body. For instance, PCBs of the display unit and the input unit are unified into one PCB.
[0031] If one element of the input unit is a touchscreen type via an LCD window, the LCD window can be used for displaying as well. So, the display unit and the input unit can be unified into one body.
[0032] The machine body can be provided with an upper attachment structure provided to an upper part of the body and a lower attachment structure under the upper part of the body to enable the user-interface unit to be selectively and detachably attached to a first or second position.
[0033] If an external input unit is provided and available at a place easily accessible, a user is able to conveniently manipulate the laundry machine by using the external input unit even without using the input unit mounted to the body. In this case, the user-interface unit can have the display unit only.
[0034] Preferably, when the user-interface unit is attached to one of the attachment structures, a cover panel is attached to the other. To attach the cover panel, the upper or lower attachment structure can be used or other attachment structure, such as a screw locking hole and the like, provided for only the cover panel can be used. What should be noted here is that the cover panel is attached to the other side where the user-interface unit is not attached. And, this does not mean that the upper or lower attachment structure is naturally used for the attachment of the cover panel.
[0035] In the present invention, the attachment structures can have any type and any shape, if they can function as needed. The attachment structures are not restricted to a specific shape. And, a related art attachment structure can be used intact. Unless deviating from the objects of the present invention, any kind of attachment structure can be employed as the attachment structure of the present invention. It is preferred to use specific attachment structures which can make the attachment of the user-interface unit easily attached and detached.
[0036] Alternatively, without providing the attachment structures to the body, magnets can be provided to the user-interface unit so that the unit can be attached to the body by the magnetic forces. Even in this case, it is more preferable that the body has attachment structures so as to provide at least places for housing the user-interface unit.
[0037] In the present invention, the body has a relative meaning to the controller. It indicates a part that performs original functions of the machine by being controlled by the controller. For instance, the washing machine body can include a drum accommodating laundry therein and a driving unit (e.g., motor, etc.) driving the drum, wherein the driving unit is controlled by the controller. Besides, a dryer body can include a drum accommodating laundry to be dried therein and a driving unit driving the drum.
[0038] In the laundry machine according to the present invention, the main control unit and the user-interface unit exchange data with each other by wireless communication. For this, communication means are provided to the main control unit and the user-interface unit.
[0039] The user-interface unit is provided with a microcomputer controlling input means such as buttons and the like or display means such as an LCD window and the like.
[0040] The microcomputer provided to the user-interface unit exchanges data with another microcomputer provided to the main control unit by wireless communications.
[0041] In case of the input unit, if a user inputs a command, the command is inputted to the microcomputer of the user-interface unit. The microcomputer then transmits the command to the microcomputer of the main control unit by wireless communications. If so, the main control unit controls the elements of the laundry machine according to the received command to perform a job.
[0042] In case of the display unit, the microcomputer of the main control unit transmits data to the microcomputer of the user-interface unit by wireless communications. If so, the microcomputer of the user-interface unit controls the display means according to the transmitted information to display prescribed information externally.
[0043] The wireless communications can be implemented in various ways. For instance, there are infrared communications used for a television remote controller or the like, radio frequency communications, blue-tooth, etc.
[0044] First of all, IrDA (Infrared Data Association) for the infrared communications was established in 1993 as an organization supported by industries to prepare international standards for hardware and software used for infrared communication link. In the infrared communications as a special type of wireless transmissions, a light beam focused within infrared frequency spectrum measured in tera- or trillion-hertz is modulated into information to be sent to a receiver within a relatively short distance. And, the infrared irradiation is carried out the same technique as used in controlling TV with a remote controller.
[0045] Infrared data communications play an important role in wireless data communications nowadays according to the popularization of laptops, PDAs, digital cameras, mobile phones, radio pagers, etc.
[0046] In the infrared communications, there should be transceivers provided to both sides, respectively. And, special microchips are provided for the function. In addition, special software is necessary for one or more devices to synchronize the communications. For example, there is a special support for IR in MS Window 95 operating system. In IrDA-1.1 standard, a length of the transmittable longest data is 2.048 bytes and a maximum data rate is 4 Mbps.
[0047] IR is usable for mutual connections in an approximately long distance and has mutual connection possibility within LAN. A maximum valid distance is about 1.5 mile and a maximum designed bandwidth is 16 Mbps. IR is carried by transmitting visible rays. So, IR is very sensitive to such an atmospheric condition as mist and the like.
[0048] Meanwhile, a terminology, radio frequency (RF), indicates an alternate current having a characteristic that an electromagnetic field suitable for radio broadcasting or communications is generated if an input entering an antenna is a current. Theses frequencies ranges between 9 kHz (lowest frequency assigned to radio communications: belonging to audible range) and several-thousand GHz to cover important parts of electromagnetic irradiation spectrum.
[0049] If a radio frequency current is supplied to an antenna, an electromagnetic field propagating through a space is generated. The magnetic field is called a radio frequency magnetic field or a radio wave. Every radio frequency magnetic field has a wavelength inverse-proportional to a frequency. If a frequency and a wavelength are set to ‘f’ and ‘s’, respectively, it results in s=300/f. A radio frequency signal is inverse-proportion to a quantity corresponding to an electromagnetic wavelength. A free space wavelength at 9 kHz is about 33 km. An electromagnetic wavelength at the highest radio frequency is about 1 mm. As a frequency increases over a radio frequency spectrum, electromagnetic energy becomes infrared rays, visible rays, ultraviolet rays, gamma rays, etc.
[0050] Most of the radio equipments use radio frequency magnetic fields. Cordless phones, mobile phones, radio or TV broadcasting stations, satellite communication systems, interactive radiotelegraphs and the like work within the radio frequency spectrum. Some of the radio equipments work in IR or visible ray frequency having an electromagnetic wavelength shorter than that of a radio frequency magnetic field. For example, there are TV remote controllers, wireless keyboards, wireless mouse, wireless headphone sets, etc.
[0051] The radio frequency spectrum is divided into several kinds of bands. Except a lowest frequency band, each zone means a frequency ascent according to an order of size (power of 10). Eight bands within a radio frequency band are described in the following table, which shows a frequency and a range of bandwidth. SHF and EHT bands are often called a ultra high frequency spectrum.
[0052] Bluetooth is the specification of computer and communication industries, which facilitates mobile phones, computers, PDAs and the like to be connected to phones and computers of home or office that uses wireless LAN. Bluetooth is the name of the legendary Danish King. Bluetooth was developed by the consortium of five companies, Intel, IBM, Nokia, Ericsson and the like. To use this technique, each device needs a cheap transceiver chip.
[0053] Each device is equipped with a microchip transceiver capable of transmission/reception at 2.45 GHz that is a globally available frequency band (yet, some countries may use different frequency bands). Audio channels can be used as many as three except data channel. Each device has a unique 48-bit address from IEEE 802 standard. Point-to-point access or point-to-multipoint access is possible. And, a maximum communication available range is 10 m. And, a data rate is 1 Mbps (maximum 2 Mbps by the second generation technique). A frequency hop design enables communication in an area experiencing massive electromagnetic hindrance. And, loaded encryption and verification functions are provided.
[0054] Meanwhile, a dual laundry machine according to the present invention includes a pair of laundry machines arranged parallel with or vertical to each other. At least one of a pair of the laundry machines includes a main control unit controlling an operation of the laundry machine and a user-interface unit having an input unit receiving an input of a command for an operation from a user or a display unit displaying information associated with the operation. The user-interface unit can be detached from the machine easily disconnected electrically from the main control unit. The user-interface unit wirelessly communicates data with the main control.
[0055] In the laundry machine, the number of electric wires used for the controller is minimized. The main control unit and the user-interface unit are separated from each other to enable free movements. Since the user-interface unit can be easily disconnected from the main control unit and detached from the machine body, maintenance for the user-interface unit can be carried out easily.
[0056] In addition, due to the wireless communication, the place exchange of the user-interface unit between the first position and the second position can be achieved easily.
[0057] The selectively place exchangeable user-interface unit provides many effects as follows.
[0058] Wherever, even at a high place, the laundry machine is placed, it can be conveniently used. So, less limitation is put on the place where the machine is located than the conventional laundry machine.
[0059] In the dual laundry machine including a dryer and a washing machine, a user can arrange the dryer and the washing machine not only parallel but also vertically. The arrangement diversity brings affirmative effects and enables less limitation to be put on an installation place and space.
[0060] Meanwhile, the laundry machine according to the present invention can be more usefully used by a launderette that commercially uses many dryers and washing machines. For instance, if a user-interface unit of one of a plurality of dryers is out of order, a user-interface unit of another dryer is disassembled to be assembled to the out-of-order dryer for a temporary solution. If a body of one dryer is out of order and if a user-interface unit of another dryer is out of order, the user-interface unit of the latter dryer can be replaced by a user-interface unit of the former dryer to complete one dryer that works normally.
[0061] It is to be understood that both the foregoing general description and the following detailed description of the present invention are exemplary and explanatory and are intended to provide further explanation of the invention as claimed.
BRIEF DESCRIPTION OF THE DRAWINGS
[0062] The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the invention and together with the description serve to explain the principle of the invention. In the drawings:
[0063] FIG. 1 is a perspective diagram of a drum type washing machine according to a related art;
[0064] FIG. 2 is a perspective diagram of a dryer according to a preferred embodiment of the present invention;
[0065] FIG. 3 is an exploded perspective diagram of a user-interface unit assembled to a body in the dryer shown in FIG. 2 ;
[0066] FIG. 4 is a perspective diagram of the dryer shown in FIG. 2 to show enlarged cross-sections of a user-interface unit attached to a body;
[0067] FIG. 5 is an exploded perspective diagram of the dryer shown in FIG. 2 to show a cover panel assembled to a body;
[0068] FIG. 6 is a block diagram of a main control unit, an input unit and a display unit to explain wireless communications therebetween;
[0069] FIG. 7 is a perspective diagram of a dual laundry machine according to one embodiment of the present invention; and
[0070] FIG. 8 is a perspective diagram of a dual laundry machine according to another embodiment of the present invention, which shows a dryer is installed on a washing machine.
DETAILED DESCRIPTION OF THE INVENTION
[0071] Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts.
[0072] FIG. 2 is a perspective diagram of a dryer according to a preferred embodiment of the present invention.
[0073] Referring to FIG. 2 , a user-interface unit 110 of a controller is provided to an upper part of a dryer body 100 and a cover panel 120 is provided to a lower part of the dryer body 100 .
[0074] The user-interface unit 110 and the cover panel 120 are detachably provided to the body 100 and can be easily detached from the body 100 . And, installed positions of the user-interface unit 110 and the cover panel 120 can be mutually switched. In more detail, the user-interface unit 110 is detached from the body 100 and then provided to the lower part of the body 100 where the cover panel 120 was provided. And, the cover panel 120 is attached to the upper part of the body 100 where the user-interface unit 110 was attached.
[0075] FIG. 3 is an exploded perspective diagram of a user-interface unit assembled to a body in the dryer shown in FIG. 2 .
[0076] Referring to FIG. 3 , the user-interface unit 110 will be attached to the upper part of the body 100 .
[0077] First of all, in the present embodiment, a main control unit 130 of a controller is provided within the body 100 . And, the user-interface unit 110 includes an input unit and display unit built in one body.
[0078] The user-interface unit 110 , as shown in FIG. 3 , is provided with various buttons and a knob as an input unit to input drying conditions for the laundry drying and the like. And, the user-interface unit 110 is also provided with an LCD window or an LED as a display unit to display a signal received from the main control unit 130 .
[0079] The various buttons, knob, LCD, LED and the like are provided to a the user-interface unit PCB (not shown in the drawing). And, the user-interface unit PCB is fixed to a user-interface unit panel 113 . In this case, the user-interface unit PCB is configured with an input unit PCB for the input unit only and a display unit PCB separated from the input unit PCB for the display unit only. Preferably, the input unit PCB and the display unit PCB are unified into one PCB to be built in one body.
[0080] A screw locking hole 115 and a projection 177 for a locking are provided to both sides of the user-interface unit panel 113 to be attached to upper attachment structures 103 and 104 and lower attachment structures 143 and 144 , respectively.
[0081] The upper attachment structures 103 and 104 provided to the body 100 include the screw locking hole 103 provided to one side of an upper frame 102 of the body 100 and the slot 104 locked to the projection 117 provided to the user-interface unit panel 113 .
[0082] FIG. 4 is a perspective diagram of the dryer shown in FIG. 2 to show enlarged cross-sections of a user-interface unit attached to a body.
[0083] How to attach the user-interface unit 110 to the body 100 is explained with reference to FIG. 4 and FIG. 3 as follows.
[0084] First of all, the upper frame 102 is assembled to a front cabinet 101 of the body 100 . While the state of the body 100 is maintained, the user-interface unit 110 is misaligned in a slightly right direction with the upper frame 102 and then slides to move in a right direction. If so, the projection 117 provided to the user-interface unit panel 113 is fitted into the slot 104 provided to the upper frame 102 to be locked thereto. In this case, one side of the projection 117 , as shown in FIG. 4 , is configured to be bent and the slot 104 is bent to correspond to the configuration of the projection 117 . So, once the projection 117 and the slot 104 are locked together, the user-interface unit 110 is prevented from being separated from the body 100 in a front direction.
[0085] After completion of this assembly, screws are fitted into the screw locking hole 103 provided to the upper frame 102 and the screw locking hole 115 provided to the user-interface unit panel 113 , respectively. Hence, the attachment of the user-interface unit 110 is secured.
[0086] While the user-interface unit 110 is attached to the upper part of the body 100 , a deco-plate can be further provided for an exterior.
[0087] FIG. 5 is an exploded perspective diagram of the dryer shown in FIG. 2 to show the cover panel 120 assembled to a lower part of the body 100 .
[0088] Referring to FIG. 5 , like the user-interface unit panel 113 , a screw locking hole 121 and a projection (not shown in the drawing) are preferably provided to the cover panel 120 . Alternatively, it is a matter of course that the attachment structure of the cover panel 120 can be configured different from that of the user-interface unit panel 113 .
[0089] A lower frame is provided to the lower part of the body 100 to correspond to the upper frame 102 . Like the upper frame 102 , the lower fame is provided with a slot 144 and a screw locking hole 143 .
[0090] How to assemble the cover panel 120 to the lower frame is the same as assembling the user-interface unit 110 , and more particularly, the user-interface unit panel 113 to the upper frame 102 , which is omitted in the following description.
[0091] Communications between the user-interface unit 110 and the main control unit 130 mounted in the body 100 are explained with reference to FIG. 6 as follows.
[0092] First of all, if a user inputs commands using input keys of the input unit 170 , the input unit 170 transmits the inputted commands to the main control unit 130 via a transmitter.
[0093] The main control unit 170 controls a dryer operation according to the commands sent from the input unit 170 and then transfers associated information to the display unit 180 via a transmitter.
[0094] The display unit 180 receives the information transmitted by the main control unit 130 and then displays the associated information according to the received information.
[0095] The main control unit 130 generally includes a microcomputer and a memory. The main control unit 130 controls a motor to drive a drum, a heater to heat air to be supplied within the drum, a blower to blow the air heated by the heater into the drum, thereby enabling the dryer to perform a drying course.
[0096] Meanwhile, the embodiment shown in the drawing is just exemplary and can be modified in various ways that can be easily implemented by those skilled in the art.
[0097] For instance, unlike the embodiment described above, the input unit and the display unit can be separately configured from each other so that the attaching positions of the respective units can be switched independently.
[0098] A dual laundry machine according to the present invention is shown in FIG. 7 or FIG. 8 .
[0099] FIG. 7 shows that a dryer 150 is provided next to a washing machine 160 in parallel. FIG. 8 shows that the dryer 150 shown in FIG. 2 is placed on the washing machine 160 .
[0100] The dryer 150 shown in FIG. 7 or FIG. 8 corresponds to the former dryer shown in FIG. 2 and the washing machine corresponds to the related art washing machine. So, detailed explanations of the dryer 150 and the washing machine 160 are omitted in the following description.
[0101] Referring to FIG. 7 , in case that the dryer 150 and the washing machine 160 are arranged parallel with each other, the user-interface unit 110 of the dryer 150 is assembled to the upper part of the body 100 .
[0102] Referring to FIG. 8 , if the dryer 150 is placed on the washing machine 160 , the user-interface unit 110 is assembled to the lower part of the body 100 .
[0103] Hence, a user is facilitated to perform a manipulation of the user-interface unit 100 if the dryer 150 is arranged next to the washing machine 160 in parallel or even if the dryer 150 is placed on the washing machine 160 .
[0104] It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the inventions. Thus, it is intended that the present invention covers the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents. | A washing machine having a wireless communicating controller therein is disclosed, by which electric wires used for a controller in the washing machine are reduced and by which a main control unit is separated from an input unit or a display unit to secure a free movement and by which an installation position of an input unit or a display unit can be easily changed. | 3 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] Not Applicable
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] Not Applicable
REFERENCE TO SEQUENCE LISTING
[0003] Not Applicable
BACKGROUND OF THE INVENTION
[0004] 1′-Acetoxychavicol acetate, whose structure is shown below, is a natural compound, which is found in some plants in the family Zingiberaceae especially in greater galingale ( Alpinia galanga (Linn.) Sw.) and big galingale ( Alpinia nigra (Gaertn.) B. L. Burtt). It is not found in several of other members of this family, such as Zingiber officinale, Kaempferia galanga and Alpinia officinarum, which is used as medicine in China. Galingales have been used as herb and food in Thailand and other countries in Asia for a long time.
[0005] Many investigators reported growth-inhibiting activities of 1-acetoxychavicol acetate against many organisms. It could inhibit the growth of various fungi (Jassen, A. M. and Scheffer, J. J. C. 1985), including many dermatophytic fungi such as Trichophyton mentagrophytes, Trichophyton rubrum, Trichophyton concentricum and Epidermophyton floccosum with the minimal inhibitory concentrations (MIC) between 50-250 μg/ml. It also inhibited the growth of several other fungi such as Rhizopus stolonifer, Penicillium expansum, Aspergilus niger, albeit with higher MIC. This compound could not inhibit the growth of the yeast Candida albicans, and many bacteria, such as Escherichia coli, Pseudomonas aeruginosa and Bacillus subtilis but could slightly inhibit the growth of Staphylococcus aureus.
[0006] There has been no existing report on the inhibitory activity against the growth of M. tuberculosis and other mycobacterium of this compound.
[0007] 1′-Acetoxychavicol acetate can inhibit the formation of many tumor and cancer in mice experimental models, such as skin cancer (Murakami, A. et.al., 1996), bile duct cancer (Miyauchi, M. et.al. 2000), esophageal cancer (Kawabata, K. et.al. 2000), large intestinal cancer (Tanaka, T. et.al. 1997 and Tanaka, T. et.al. 1997), oral cancer (Ohnishi, M. et.al. 1996) and liver tumor (Kobayashi, Y. et.al. 1998).
[0008] The mechanisms of action of the compound were not clear. The compound could inhibit the activation of tumor virus such as Ebstein-Barr virus (Marukami, A. et.al. 2000 and Kondo, A. et.al. 1993), and could inhibit the function of xanthine oxidase and NADPH oxidase (Noro, T. et.al. 1998 and Tanaka, T. et.al. 1997). These enzymes involve in superoxide anion production, which is one of the spontaneously occurring toxic substances in the body (Nakamura, Y. et.al. 1998 and Murakami, A. et.al. 1996).
[0009] 1′-Acetoxychavicol acetate can inhibit nitric oxide synthase production in RAW264 (mice macrophage) cell line when stimulated with mice interferon-γ or bacterial lipopolysaccharides (Ohata, T. et.al. 1998). 1′-acetoxychavicol acetate at the concentration of 250 could completely inhibit nitric oxide synthase production when stimulated with 100 ng/ml of bacterial lipopolysaccharide. The enzyme production was 80% inhibited when stimulated with 100 ng/ml of interferon-γ. This compound was about 10 times more potent than the other nitric oxide synthase inhibitors such as curcumin, nonsteroidal anti-inflammatory drugs, genistein and ω-3 polyunsaturated fatty acids. 1′-Acetoxychavicol could inhibit nitric oxide synthase by inhibiting the destruction of IκB-α protein, which is an inhibitor of NF-κB (a transcription factor), leading to the decrease of the NF-κB activity and, consequently, resulting in decreased nitric oxide synthase production. It also inhibited other transcription factors such as AP-1 and Stat-1. It has been suggested that nitric oxide, which is produced by nitric oxide synthase, involves in tumor formation.
[0010] Greater galingale ( Alpinia galanga (Linn.) Sw. or Languas galanga (Linn) Stuntz.) and big galingale ( Alpinia nigra (Gaertn.) B.L. Burtt) belong to the family Zingiberaceae. The galingales are found in Asia, from India, Indonesia to Philippines. They are used as food and herb in Thailand. As herb, the galingales are generally used as anti-flatulence, to decrease the gastric discomfort and to treat dermatophytic fungal infection. It was noted in a Thai ethnomedicinal textbook that galingale oil could be used for tuberculosis treatment.
[0011] It was reported that greater galingale did not produce acute toxic effects in mice even at the dose as high as 3 g/kg body weight and did not have chronic toxicity when given to mice at the dose of 100 mg/kg bodyweight for 90 days. It was found that it did not affect the body weight or the weights of any organs including heart, lung, liver, spleen, and kidney. It increased the number of red blood cells but not white blood cells. It increased the weight of sex organs in male mice with the increase of sperm number and sperm movement. It was not toxic to sperm (Qureshi, S. et.al. 1992 and Mokkhasmit, M. et.al. 1971). In contrast, it decreased the toxicity of cyclophosphamide in mice (Qureshi, S. et.al. 1994).
[0012] 1′-Acetoxychavicol acetate can be found in high concentration, of about 1.5%-2.8% of dry weight, in the greater galingale root (De Pooter, H. L. et.al. 1985), but less in the leaf (Jassen, A. M. and Scheffer, J. J. C. 1985). The configuration of 1′-acetoxychavecol naturally found in the galingale is in S-form.
[0013] Many chemicals have been reported in greater galingale. These included galingin, 3-methygalangin (Ramachandran, N. and Gunasegaran, R. 1982), 1′-hydroxychavicol acetate, 1′-acetoxyeuginol acetate (Jassen, A. M. and Scheffer, J. J. C. 1985), p-hydroxycinnamaldehyde, [di-(p-hydroxy-cis-styryl)] methane (Barik, B. R. 1987), galanal A, galanal B, galanolactone, (E)-8(17),12-labddiene-15,16-dial, (E)-8β(17), epoxylabd-12-ene-15,16-dial (Morita, H. and Itokawa, H. 1987).
[0014] Tuberculosis, caused by Mycobacterium tuberculosis, is an important communicable disease. Mycobacterium is a genus of bacteria, which have special cell membrane structures different from other bacteria. This renders most antibiotics unable to enter the bacterial cells, leading to failure in inhibiting the growth of the bacteria. Tuberculosis, therefore, requires special drugs for treatment.
[0015] Anti-tuberculosis drugs can be divided into two groups. The first line drugs, are highly effective and of relatively low toxicity. The second line drugs, are less effective and/or of relatively high toxicity. The drugs are used when the bacteria resist the first line drugs.
[0016] There are 5 first line drugs, which are isoniazid, rifampin, pyrazinamide, ethambutol and streptomycin. Standard tuberculosis treatment requires 4 in the 5 drugs. There must be isoniazid and rifampin with two other drugs, usually pyrazinamide and ethambutol or streptomycin. The 6-month-long treatment starts with these 4 drugs for 2 months, followed by treatment with isoniazid and rifampin for 4 months. This is because only isoniazid and rifampin are highly effective in killing the bacteria. When M. tuberculosis resists to any of pyrazinamide, ethambutol or streptomycin, the treatment requires the switch to second line drugs and still might be able to complete the treatment in 6 months. On the other hand, if the organisms resist to isoniazid or rifampin, even the switch to other effective drugs may not render the treatment being successful in 6 months. The treatment may need to be lengthened up to 18 months especially if the organisms resist rifampin. The M. tuberculosis is, therefore, called multi-drug resistant when resists to both isoniazid and rifampin. Multi-drug resistant tuberculosis is a very serious public health problem because it can not be cured in 6 months or the worst, not at all. This is due to the fact that the bacteria may become gradually resisting other drugs during the treatment. The patients may have no serious symptoms even though the treatment can not eliminate the bacteria because the drugs may control the organisms to some extent. The patients can therefore survive and transmit the resistant strains to the other people.
[0017] The presence of limited number of the highly effective drugs is a major problem in tuberculosis control. Although, isoniazid and rifampin have been discovered for 30 years, there have been limited efforts to identify new highly effective drugs.
DETAILED DESCRIPTION OF THE INVENTION
[0018] The discovery and development of new anti-tuberculous drugs are usually started by showing that a new compound can inhibit the growth of M. tuberculosis in vitro. The method includes culturing the bacteria in artificial medium, which contains the compound and then observing the growth of the bacteria. The compounds with higher activity will inhibit the growth of M. tuberculosis at a lower concentration than the compounds with lower activity. The activity of each drug can be compared by its minimal inhibitory concentration (MIC).
[0019] The growth of M. tuberculosis can be measured by several methods such as observing colony formation in solid media or turbidity in liquid media. However, the observation of the slow growing M. tuberculosis is possible only after a long period of incubation. Many investigators tried to find a way to observe the growth in a shorter time. The M. tuberculosis usually grows more rapidly in liquid media than in solid media. Therefore, the tests for drug development are usually done in liquid media.
[0020] Several indirect growth observation methods have been developed for clinical use. These include observing the production of radioactive carbon dioxide in BACTEC460 system (Middlebrook, G. et.al. 1997), the oxygen in Mycobacterium Growth Indicator Tube (Pfyffer, G. E. et.al. 1997) or the bioluminescence from the luciferase enzyme that is transducted into M. tuberculosis by a specially-engineered virus (Arain, T. M. et.al.). Most of these methods can decrease the test period from 3-4 weeks to only 7-10 days.
[0021] Many of the systems, marketed for clinical use, require high amount of media and consequently high amount of samples. They are, therefore, not suitable for drug development. The methods specifically designed for drug development are usually done in microplate. The small wells allow the use of small amount of culture media and tested compounds. A popular microplate test uses the bacteria containing luciferase enzyme as surrogate host. The growing bacteria produce the luciferase enzyme, rendering it bioluminescent. Another method measures the oxygen content in the microplate by observing the color change of Alamar Blue (Collins, L. and Franzblau, S. G. 1997) or other dyes.
[0022] Anti-tuberculous drugs must have low toxicity because the patients need to ingest it for a long time. Primary testing for toxicity is usually done by incubates the candidate compounds with human cells which the cells were cultivated in vitro and then observes the cytopathic effects. In principle, every chemical compound is toxic to human cells at a high enough concentration. The chemical compound that may be used as drug must have the ability to inhibit growth of organisms at a lower concentration and is toxic to human cells at a higher concentration, such as at the concentration more than 10 fold higher than the MIC. The compound can then theoretically be administered to human to achieve concentration between MIC and the toxic concentration.
[0023] The appropriate compounds for the 1′-acetoxychavicol acetate may be readily prepared by methods known to those skilled in the art. The preferred method for the preparation of 1′-acetoxychavicol acetate involves the following steps a) to d):
[0024] a) Preparation of 1′-acetoxychavicol Acetate from Galingale
[0025] Extraction and purification of the compound was done starting from slicing the root of greater galingale ( Alpinia galanga (Linn.) Sw.) or big galingale ( Alpinia nigra (Gaertn) B. L. Burtt). The slices were air-dried and then ground, following by dichloromethane extraction. The extracts were then dried, resolubilized and purified by silica gel column. After elution with dicloromethane:hexane (1:1), the elute was distilled at 170-190° C. to recover pure 1′-acetoxychavicol acetate. The yield of 1′acetoxychavicol acetate was about 60 gm/kg of the galingales.
[0026] b) Preparation of Bacteria to Test 1′-acetoxychavicol Acetate Against M. tuberculosis
[0027] [0027] Mycobacterium tuberculosis H 37 Ra strain (ATCC 25166) was grown in 100 ml of Middlebrook 7H9 broth supplemented with 0.2% glycerol, 1.0 gm/L of casitone, 10% OADC, and 0.05% Tween 80. The complete medium was referred to as 7H9GC-Tween. The bacteria were incubated in 500-ml flasks on a rotary shaker at 200 rpm and 37° C. until the optical density at 550 nm reached 0.4-0.5. The bacteria were washed twice with phosphate-buffered saline and then suspended in 20 ml of phosphate-buffered saline. The suspension was passed through an 8-μm-pore-size filter to eliminate clumps. The number of the bacteria in the filtrates was counted by plating the bacteria in Middlebrook 7H10 agar. The filtrates were stored at −80° C.
[0028] c) Microplate Alamar Blue assays (MABA)
[0029] Anti-tuberculous testing was performed in a 96-well microplate as previously described (Collins, L. and Franzblau, S. G. 1997). Outer perimeter wells were filled with sterile water to prevent dehydration of the test wells. Crude extracts were initially diluted in dimethyl sulfoxide, and then were diluted to a concentration of 400 μg/ml in Middlebrook 7H9 medium containing 0.2% V/V glycerol and 1.0 gm/L casitone (7H9GC). The wells in rows B to G in columns 2, 4, 5, 6, 8, 9, 10 of the microplate were inoculated with 100 μl of 7H9GC. The wells in column 11 were inoculated with 200 μl of the medium to serve as media controls (M). Bacteria (only) controls (B) were set-up in column 10. One hundred microliters of each crude extract solution (400 μg/ml) were added to three wells in one row in columns 2 (or 6), 3 (or 7) and 4 (or 8). One hundred microliters was transferred from column 4 (or 8) to column 5 (or 9), the contents of the wells in column 5 (or 9) were mixed well and then 100 μl of mixed medium were discarded. The wells in columns 2 and 6 served as test sample controls.
[0030] Frozen bacterial inocula were diluted 1:200 in 7H9GC medium. One hundred microliters of the bacteria were added to the wells in rows B to G in columns 3 (or 7), 4 (or 8), 5 (or 9) and 10 resulting in final bacterial titers of about 5×10 4 CFU/ml. The wells in column 10 served bacteria (only) controls (B). Final concentrations of extracts were 200, 100 and 50 μg/ml in columns 3 (or 7), 4 (or 8) and 5 (or 9), respectively.
[0031] The plates were sealed with Parafilm and were incubated at 37° C. for 5 days. At day 6 of incubation, 20 μl of Alamar Blue reagent and 12.5 μl of 20% Tween 80 were added to well B10 (B) and B11 (M). The plates were re-incubated at 37° C. for 24 h. Wells were observed at 24 h for color change from blue to pink. If the B wells became pink by 24 h, reagent was added to the entire plate. If the well remained blue, the additional M and B wells was tested daily until a color change occurred at which time reagents were added to all remaining wells. The microplates were resealed with Parafilm and were then incubated at 37° C. The results were recorded at 24 h post-reagent addition.
[0032] A blue color in the well was interpreted as no growth, reflecting the activity of the test compound in the well. A pink color was scored as growth and reflected the lack of activity of the test compound. A few wells appeared violet after 24 h of incubation, but they invariably changed to pink after another day of incubation and thus were scored as growth (while the adjacent blue wells remained blue).
[0033] When 1′-acetoxychavicol acetate was found to be active at the concentration of 50 μg/ml, the activity of the compound was tested in the second plate containing the compound at two-fold serially diluted from 50 to 0.025 μg/ml. 1′-acetoxychavicol acetate can inhibit the growth of M. tuberculosis at the concentration of 0.1 μg/ml or higher but not at the concentration of 0.05 μg/ml or lower. The MIC of 1′-acetoxychavicol acetate against M. tuberculosis H 37 Ra was therefore 0.1 μg/ml.
[0034] The activity of the compound was also tested for 30 clinical strains of M. tuberculosis isolated from patients in Thailand. The MICs were found to be between 0.1-0.5 μg/ml. The clinical isolates included isoniazid and/or rifampin resistant strains.
[0035] d) The Toxicity of 1′-acetoxychavicol Acetate
[0036] 1′-acetoxychavicol acetate was tested for toxicity by incubating it with Vero cells (African green monkey kidney cell line from American Type Culture Collection USA). 1′-acetoxychavicol acetate was dissolved with dimethyl sulfoxide and then diluted in the culture medium of the Vero cells (Eagle's minimum essential with 10% heat-inactivated fetal bovine serum and antibiotics). The Vero cells and the compound were incubated together in a 96-well microplate at the cell concentration of 1.9×10 4 cells/ 190 μl/well, in a CO 2 incubator at 37° C. for 3 days. The numbers of the cells in the wells were then determined by a staining method (Skehan, P. 1990). The cells were firstly fixed by 50% cold trichloroacetic acid (TCA) at 4° C. for 30 minutes. The cells were then washed with water 4 times. After drying, the cells were stained with 0.05% sulforhodamine B in 1% acetic acid for 30 minutes, washed with 1% acetic acid 4 times and dried at room temperature. Finally, 10 mM Tris-base pH10 was added. The absorbance at 510 nm of test wells was measured by an ELISA microplate reader. The absorbance was proportionate to the number of the viable cells in the wells. The toxic level of the compound was recorded as the concentration that rendered the number of viable cells being less than half of the negative control wells, which contained the cells with DMSO but not the compound. The test was done at least 3 times per concentration. Ellipticine was used as positive control. The toxic level of 1′-acetoxychavicol acetate against Vero cells was found to be 2.0 μg/ml, which was 20 times higher than the MIC against M. tuberculosis H 37 Ra.
[0037] 1-Acetoxychavicol acetate was also tested for toxicity against three other mammalian cell lines, namely L929 (mouse lung cells), BHK21 (hamster kidney cells) and HepG2 (human liver cells) by culturing the cells in microplates together with various concentration of the compounds. The toxic levels were again defined as the concentration that decrease the viability of the cells by half compared to the negative control, which contain no compound. The viability of these cells were determined by adding MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) solution into wells after 48 hours of co-incubation of the cells with the compound. The viable cells converted the soluble MTT to insoluble formazan precipitate. After 4 hours of incubation, aqueous phase of the wells was removed and dimethyl sulfoxide was added to disslove the formazan. Sorensen's glycine buffer pH 10.5 was then added and the absorbance at 570 nm was measured and compared to the absorbance of the negative control wells.
[0038] The toxic levels of the compound for L929 and BHK21 cells were found to be 7.0-8.5 μg/ml, while the toxic level against HepG2 cells was 23.4 μg/ml.
REFERENCE
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[0040] 2. Barik, B. R., Kundu, A. B, and Dey, A. K. Two phenolic constituents from Alpinia galanga rhizome. Phytochemistry 1987;26:2126-2127.
[0041] 3. Collins, L., and Franzblau, S. G. Microplate alamar blue assay versus BACTEC 460 system for high- throughput screening of compounds against Mycobacterium tuberculosis and Mycobacterium avium. Antimicrobl Agents Chemother 1997;41:1004-1009.
[0042] 4. De Pooter, H. L., Omar, M. N., Coolsaet, B. A., and Schamp, N. M. The essential oil of greater galanga ( Alpinia galanga ) from Malaysia. Phytochemistry 1985;24:93-96.
[0043] 5. Jassen, A. M. and Scheffer, J. J. C. Acetoxyhydroxychavicol acetate, an antifungal component of Alpinia galanga. Planta Med 1985;6:507-11.
[0044] 6. Kawabata, K., Tanaka, T., Yamamoto, T. et. al. Suppression of N-nitrosomethylbenzylamine-induced rat esophageal tumorigenesis by dietary feeding of 1′-acetoxychavicol acetate. Jpn J. Cancer Res 2000;91:148-155.
[0045] 7. Kobayashi, Y., Nakae, D., Akai, H. et. al. Prevention by 1′-acetoxychavicol acetate of the induction but not growth of putative preneoplastic, glutathione-S-transferase placental form-positive, focal lesions in the livers of rats fed a choline-deficient, L-amino acid-defined diet. Carcinogenesis 1998;19:1809-1814.
[0046] 8. Kondo, A., Ohigashi, H., Murakami, A., Suratwadee, J., and Koshimizu, K. 1′-Acetoxychavicol acetate as a potent inhibitor of tumor-promoter-induced Epstein-Barr virus activation from Languas galanga, a traditional Thai condiment. Biosci Biotechnol Biochem 1993;57:1344-1345.
[0047] 9. Marukami, A., Toyota, K., Ohura, S., Koshimizu, K., and Ohigashi, H. Structure-activity relationships of (1′S)-1′-acetoxychavicol acetate, a major constituent of a Southeast Asian condiment plant Languas galanga, on the inhibition of tumor-promoter-induced Epstein-Barr virus activation. J. Agric Food Chem 2000;48:1518-1523.
[0048] 10. Middlebrook, G., Reggiardo, Z., and Tigertt, W.D. Automatable radiometric detection of growth of Mycobacterium tuberculosis in selective media. Am Rev Respir Dis 1977; 115: 1067-1069.
[0049] 11. Mitsui, S., Kobayashi, S., Nagahori, H., and Ogiso, A. Constituents from seeds of Alpinia galanga Wild and their anti-ulcer activities. Chem Pharm Bull 1976;24:2377-2382.
[0050] 12. Miyauchi, M., Nishikawa, A., Furukawa, F. et. al. Inhibitory effects of 1′acetoxychavicol acetate on N-nitrosobis (2-oxopropyl) amine-induced initiation of cholangiocarcinogenesis in syrian hamsters. Jpn J. Cancer Res 2000;91:477-481.
[0051] 13.Mokkhasmit, M., Sawasdimongkol, K., and Satravaha, P. Toxicity study of Thai medicinal plants. Bull Dept Med Sci, Thailand 1971; 12, 2-4: 36-66.
[0052] 14. Morita, H. and Itokawa, H. Cytotoxic and antifungal diterpenes from the seed of Alpinia galanga. Planta Med 1988;9:117-120.
[0053] 15. Murakami, A., Ohura, S., Nakamura, Y. et. al. 1′acetoxychavicol acetate, a superoxide generator inhibitor, potently inhibits tumor promotion by 12-O-tetradecanoylphorbol-13-acetate in ICR mouse skin. Oncology 1996;53:386-391.
[0054] 16.Nakamura, Y., Marukami, A., Ohto, Y., Torikai, K., Tanaka, T., and Ohigashi, H. Suppression of tumor promoter induced oxidative stress and inflammatory responses in mouse skin by a superoxide generator inhibitor 1′-acetoxychavicol acetate. Cancer Res 1998;58:4832-4839.
[0055] 17. Noro, T., Sekiya, T., Katoh, M. et. al. Inhibitors of xanthine oxidase from Alpinia galanga. Chem Pharm Bull 1988;36:244-248.
[0056] 18. Ohata, T., Fukudal, K., Murakami, A., Ohigashi, H., Sugimural, T., and Wakabashil, K. Inhibition by 1′-acetoxychavicol acetate of lipopolysaccharide- and interferon-gamma-induced nitric oxide production through suppression of inducible nitric oxide synthase gene expression in RAW264 cells. Carcinogenesis 1998;19:1007-1012. | 1′-Acetoxychavicol acetate is a compound not known before to possess anti-tuberculous activity. The above data revealed that the compound was active against the standard H37Ra strain as well as several clinical isolates at the concentration well below the toxic concentration against various mammalian cells. The compound is therefore potentially useful as an therapeutic and preventive agent for tuberculosis as well as an antiseptic agent against the bacteria. | 0 |
This is a division of application Ser. No. 08/252,449, filed Jun. 1, 1994.
BACKGROUND
1. Field of the Invention
The invention relates to an improved imprinting felt for use in the production of paper. The imprinting felt of the present invention contains a low level of sheet side batting and is treated with a polymer. Sheet side refers to the side of the felt which contacts the wet paper web during manufacture.
The invention further relates to an improved papermaking process using the imprinting felt. The imprinting felt of the present invention simultaneously pattern presses and dewaters the paper web.
The invention also relates to an improved paper product produced using the improved papermaking process. The paper produced according to the present invention has increased paper bulk and absorbency without having reduced strength.
2. Background of the Invention
Papermaking processes for manufacturing paper webs for use as, or in the production of tissue, towel, and sanitary paper products require the removal of water from the paper web. There are two major types of machines used for the production of these products. One type is the conventional wet press machine which is generally represented by a wet fibrous web being deposited on a Fourdrinier wire, drained with or without the aid of vacuum, transferred to a press felt and pressed onto a cylindrical drying surface. After drying, the web is creped from the drying surface and processed through a series of converting steps which may include embossing, application of glue, and lamination to form a multilayer product.
The felt used in conventional wet pressing is composed of a woven base fabric covered with batting. The base fabric provides a support for the batting and allows stable running of the felt on the paper machine. The batting material is normally a fine cut nylon filament that is needle punched onto the base fabric. The batting provides water holding capacity, forms fine capillaries that reduce the amount of rewet as the wet web exits the pressure nip and protects the base fabric from excessive machine wear.
It is important in conventional wet pressing operations, that the wet web be uniformly pressed onto the surface of the cylindrical drying surface, hereinafter referred to as a Yankee dryer. The uniform pressing of the wet web has both beneficial and detrimental effects on the drying process and paper structure. Uniform pressing reduces the amount of water that needs to be evaporated during drying of the paper web. It increases the drying rate and consolidation of the web structure, thus increasing the paper strength, but reducing the bulk and absorbency of the dried paper.
The other major type of papermaking machine for the production of absorbent and bulky paper is represented by the through-air-drying machines, one representation of which is described in U.S. Pat. No. 3,301,746 to Sanford et al., which is incorporated by reference in its entirety herein. In the process disclosed in Sanford et al., the wet paper web is pressed onto the imprinting fabric. An imprinting felt is a fabric that imprints a knuckle type pattern onto the paper web. For the purposes of the present invention, felt is understood to include a press fabric both with and without batting. After the web is placed onto an imprinting felt, it is pre-dried in an air-through-dryer. The partially dried paper web is pressed by the imprinting fabric onto the surface of the cylindrical dryer/yanker without disturbing the imprinted knuckle pattern. By contrast to the conventional wet pressing process, which uses an overall pressing, the web in Sanford et al. is pressed with the fabric knuckle pattern. While water removal and drying rates are reduced due to the non-uniform pressing, the absorbency and bulk of the paper are increased.
While the through-air-drying process of Sanford et al. increases the bulk, absorbency and softness of the paper produced, it has the drawbacks of being more complex, less efficient than conventional drying processes, and not easily implemented with existing papermaking machines.
Conventional wet pressing and through-air-drying may be considered the two extremes for the production of towel, tissue, and sanitary paper products. Others have proposed processes that represent middle grounds of these two extremes. One such process is disclosed in U.S. Pat. No. 3,537,954 to Justus, which is incorporated by reference in its entirety herein. Justus describes two methods for imprinting a knuckle pattern on a wet fiber web and depositing the web on the surface of a dryer cylinder. The first method requires using a secondary fabric to imprint the knuckle pattern onto the web after it has been uniformly pressed on the dryer surface with a conventional felt. The second method employs an imprinting fabric containing monofilament filler (batting) between the imprinting fabric strands to increase the uniformity of contact with the dryer surface.
The methods of Justus are directed to solving the problems associated with uniformity in pressing the wet web onto the dryer surface. The methods of Justus suffer from the drawback that since the imprinting fabric is not uniformly covered with a batting, water is not effectively removed from the wet web as it is pressed on the dryer surface. Because of the lack of batting, less water can be removed from the wet web during pressing and more water reenters the web as it exits the press nip.
To solve the problems inherent in Justus and to improve water removal with an imprinting fabric, U.S. Pat. No. 4,533,437 to Curran et al. discloses a method whereby the imprinting fabric was covered with batting levels greater than 153 g/m 2 . While batting less than 162 g/m 2 does provide greater increases in bulk and absorbency as disclosed in Curran et al., Curran et al. does recognize that the batting level could not be reduced significantly below 162 g/m 2 and still adequately dewater the paper. Batting levels between 152 and 162 g/m 2 appear to increase absorbency and bulk, but do not provide acceptable dewatering. In addition to causing low productivity, fabrics with low levels of batting (for example, 150 g/m 2 ) are difficult to run on a paper machine because of pulp entangling with loose batting.
Alternative solutions to the dewatering problem have taken the form of modifying the fabric or batting. U.S. Pat. No. 3,617,442 to Hurschaman discloses that conventional batting may be replaced by a synthetic, open-celled, flexible foam, such as polyurethane. The use of foam was disclosed to provide ease of manufacture of the fabric and the extension of fabric life. In another alternative, U.S. Pat. No. 4,571,359 to Dutt discloses that the base fabric could be covered with relatively large polymeric resin particles fused together to form a porous covering. The disclosed particles are from 0.15 mm to 5.0 mm in diameter. The particles were disclosed to be fused together and to the base fabric forming a covering thereover.
The present invention overcomes the disadvantages associated with the prior art. According to the present invention, the papermaking process can be carried with low levels of batting on the imprinting felt, thereby improving the bulk and absorbency of the paper product while maintaining a sufficiently high level of dewatering of the wet paper web.
SUMMARY OF THE INVENTION
Further advantages of the invention will be set forth in part in the description which follows and in part will be apparent from the description, or may be learned by practice of the invention. The advantages of the invention may be realized and attained by means of the instrumentalities and combinations particularly pointed out in the appended claims.
To achieve the foregoing advantages and in according with the purpose of the invention, as embodied and broadly described herein, there is disclosed:
An imprinting felt for use in the production of paper including a base fabric having a sheet side batting of from about 0 to about 150 g/m 2 having applied thereto a polymer in an amount of from about 1% to about 50% based upon the combined weight of the base fabric and sheet side batting.
There is also disclosed:
An imprinting felt for use in the production of paper, including a base fabric having a sheet side batting which has a polymer applied thereto, wherein the combined weight of the sheet side batting and polymer is less than 150 g/m 2 .
There is further disclosed:
A press felt for the production of paper including a base fabric having a batting applied thereto which is further treated with polytetrafluoroethylene in an amount of from about 1% to about 50% of the total weight of the base fabric and batting on both sides thereof.
There is also disclosed:
A method of making a paper base sheet including applying a wet web to an imprinting felt, wherein the imprinting felt has a sheet side batting in an amount of from 0 to about 150 g/m 2 and which felt has been treated with a polymer in an amount of from 1% to about 50% by weight of the fabric and batting; pressing the wet web onto a dryer surface; and removing the web from the dryer surface.
Finally, there is disclosed:
A paper base sheet produced by the method using the imprinting felt as described above.
A press felt is a fabric traditionally used to contact a wet paper web and dewater the wet web. An imprinting felt is a press felt which is further used to impart a pattern to the wet paper web. An imprinting felt is woven to create areas which stand out and thus form a pattern of knuckles adjacent to the web contacting side of the felt. As the imprinting felt contacts a wet paper web either prior to or upon application of the wet web to the surface of a cylindrical dryer, the knuckles on the felt densify the wet paper web to a greater degree than does the felt surrounding the knuckles; thus, imprinting the pattern from the felt to the wet paper web.
It is well known that the use of an imprinting felt with a low level of batting is capable of producing a paper product with improved water absorbency and bulk. However, as the batting level on the press felt is reduced, the dewatering efficiency of the press felt decreases. At levels on the sheet side of 162 g/m 2 of batting or less, the dewatering efficiency of the press felt is so poor that the use of such a felt is uneconomical.
Although the imprinting felt increases sheet bulk, it also increases water load to the Yankee dryer, which results in an economically unacceptable decrease in machine speed. This increase in water loading associated with the imprinting felt has required the sheet side batting level to be at least 162 g/m 2 as described in U.S. Pat. No. 4,533,437 to Curran et al., at column 9, lines 30 to 50. The present invention allows the felt batting level to be reduced well below this limit while still providing acceptable dewatering and superior sheet bulk and absorbency.
Additional advantages of the invention will be set forth in part in the description which follows, and in part will be apparent from the description, or may be learned by practice of the invention. The objects and advantages of the invention will be realized and attained by means of the elements and combination particularly pointed out in the appended claims.
The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate various aspects of the invention and, together with the description, serve to explain the principles of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is schematic side elevation view of a papermaking apparatus for use with the imprinting felt and method of the present invention.
FIG. 2 is a graph which illustrates the effect of imprinting felts on creped sheet bulk as a function of sheet strength.
FIG. 3 is a graph which illustrates the effect of the process according to the present invention on bulk and water load to the Yankee dryer.
FIG. 4 is a graph which illustrates the effect of imprinting felts on creped sheet water absorbency as a function of wet sheet strength.
FIG. 5 is a graph which illustrates the effect of the process according to the present invention on sheet absorbency and water load to the Yankee dryer.
FIG. 6 is a photomicrograph of a cross section of a paper sheet produced with a conventional wet pressing process.
FIG. 7 is a photomicrograph of a cross section of a paper sheet produced according to the present invention.
DETAILED DESCRIPTION
The present invention involves an improved press felt for the manufacture of tissue, towel and sanitary paper products. The papermaking machine and process employs this improved felt which comprises a base fabric having a low weight of batting applied thereto and which also has a polymer applied thereto. This polymer treated imprinting felt produces an extremely bulky, absorbent, light weight paper without an unacceptable loss in productivity.
In traditional papermaking processes, the solids content of the wet web after application to the drying cylinder but before water evaporation is typically between 30 and 45% solids. In order to retain the economies of the traditional process, the dryer must be maintained at sufficient speed, which speed cannot be maintained if the percent solids of the wet web is below about 30% before water evaporation on the drying cylinder. The imprinting felt of the present invention although having low levels of batting can maintain the percent solids content of the wet web above about 30% before water evaporation on the drying cylinder.
More preferably, the imprinting felt of the present invention can dewater the wet web to a solids content of between 35 and 45% before application of the wet web to the drying cylinder. Thus, the imprinting felt of the present invention allows paper to be produced without a substantial increase in the amount of water that needs to be evaporated. The improved felts of the invention further allow paper to be produced without the paper fibers entangling with loose batting on the imprinting felt.
In the papermaking process according to the present invention, the paper web can be formed either directly on the imprinting felt or on a separate wire and transferred to the imprinting felt.
In the imprinting felt according to the present invention, the base fabric may preferably be selected from, but not limited to, nylon, polyester, acrylic or metallic wire. The base fabric is more preferably woven from nylon. The base fabric has applied thereto a batting. The batting may be produced of materials and by methods which are recognized by the skilled artisan. The batting is preferably formed from finely chopped nylon fibers which are needle punched through the base fabric.
In one embodiment of the present invention, the base fabric has applied thereto on the sheet side, a batting at a weight which is preferably less than 150 grams per square meter. The batting is more preferably applied at a weight of from about 0 to about 150 g/m 2 , even more preferably at a weight of from about 0 to about 100 g/m 2 , and most preferably from about 50 to about 130 g/m 2 .
In another preferred embodiment, the total weight of the batting and polymer treatment is from about 15 to about 150 g/m 2 , preferably from about 50 to about 130 g/m 2 , and more preferably from about 50 to about 100 g/m 2 .
According to the present invention, the press felt or imprinting felt is treated with a polymer which can either be applied as a coating to the felt or which can be applied in such a manner that it partially fills the internal voids within the felt. The weight of the polymer applied may be from about 1 to about 50% of the combined weight of the base fabric plus the batting. The polymer is preferably applied in an amount of from 1 to about 30% by weight, and more preferably from about 5 to 15% by weight, most preferably from about 6 to 8% by weight. The skilled artisan will recognize that the polymer is applied in an amount which will allow the fabric structure to be closed sufficiently to allow water retention, while not being overclosed which will result in unacceptable low water removal. The fabric must be closed sufficiently to achieve capillary size distribution which can result in dewatering of the wet paper web to a solids content of from about 30% to about 50%.
The polymer may be either a synthetic polymer resin or a synthetic polymer. The polymer is preferably selected from the group consisting of polyurethane, polytetrafluoroethylene, polyethylene, polyamide, and polyamide resins.
In one alternative to this invention the imprinting pattern does not result from the underlying base fabric strands but instead is formed directly into the imprinting through shaping of the polymer or polymer-batting composite. This may be accomplished by non-uniformly applying the polymer treatment in such a manner as to create a pattern, or by uniformly applying the polymer treatment and then removing or densifying part of the surface of the felt to create the desired pattern.
In one alternative embodiment of the present invention, press felt having a batting level which is in excess of 150 g/m 2 , more closely related to traditional non-imprinting felts, has been treated with polytetrafluoroethylene. This polymer treated press felt may not form an imprinted pattern in the paper web and thus may be used in conjunction with an imprinting mechanism, but this press felt which has been treated with polytetrafluoroethylene has improved dewatering characteristics.
The press felt and imprinting felt of the present invention are used to form paper products which have improved characteristics over the prior art paper products produced using traditional papermaking machines and processes. The paper product of the present invention is a fibrous web product, formed by deposition from an aqueous slurry of cellulosic fibers, bonded together to form a web. The fibers can be selected from well recognized fibers which include all wood fibers. The wood fibers which are preferably used in the present invention are kraft fibers, including, but not limited to, northern hard wood kraft, northern soft wood kraft, southern hard wood kraft, and southern soft wood kraft.
The web preferably has a basis weight of about 5 to 50 lbs per 3000 sq ft, geometric-mean dry and geometric-mean wet tensile in grams (force) per three inches width, an apparent bulk in cubic centimeters per gram-weight and a water absorbency of grams water absorbed per gram dry solids. When the press felt and imprinting felt of the present invention are used, bulk increases 10 to 20% and water absorbency increases 10 to 20% at no loss in strength.
The improved imprinting felt of the present invention may be used with any of the art recognized paper forming machines. These machines include, but are not limited to Fourdrinier formers, twin wire formers, suction breast roll formers and crescent formers.
FIG. 1 shows one type of papermaking machine suitable for utilizing the imprinting felt of the present invention. In FIG. 1, 10 is the head box; 12 is the diluted stock; 14 is the stock flow to the wire; 16 is the forming wire; 18, 20, and 22 are forming wire rolls which support, drive and guide the forming wire; 24 is the wet paper web on the forming wire; 26 is the forming wire, which is now supporting the wet web; 28 is the vacuum transfer roll used to help transfer the wet paper web to the imprinting felt; 30 and 34 are vacuum dewatering boxes; 32, 36, 38, and 40 are rolls used to guide, move and support the imprinting felt; 44 is the imprinting felt; 52 is the Yankee dryer; 54 is the crepe blade; 56 is the dried paper web after creping; and 58 is the reel onto which the dried paper web is wound.
In this papermaking machine the wet web 24 flows from the headbox 10 onto the forming fabric 26. The percent solids of the wet web on the forming fabric is normally in the range of 5% to 15% solids. The wet web is transferred, with the aid of a vacuum roll 28 if required, to the imprinting felt 44. The initial percent solids of the web on the imprinting felt is about 10 to 15%. In one embodiment of the present invention, vacuum may be applied in a series of slots 30 and 34 to increase the percent solids of the wet paper web and remove excess water from the imprinting felt. The application of vacuum to the imprinting felt as shown in FIG. 1 will increase the percent solids of the wet paper web to about 20% to 30% solids. Using a pressure backing roll 36, the paper web is pressed onto the surface of the dryer 52.
In a preferred embodiment, differential transfer speeds, where the imprinting felt speed is about 0 to 10% slower than the speed of the forming wire, may be used. From this point the web travels with the rotating dryer surface and is removed from the dryer with a crepe blade 54. The creped dried paper is at about 95% to 100% solids and is then wound on the reel 58.
The effect of the imprinting felts with low levels of batting on sheet bulk is shown in FIG. 2. This figure shows that the use of these imprinting felts increases bulk by as much as 30%. Both the untreated imprinting felt and the polymer treated imprinting felt tend to produce similar increases in bulk.
The use of the polymer treatment on the imprinting felt and the use of vacuum applied to the wet web on the imprinting felt significantly increases the dewatering ability of the imprinting felts and enables an imprinting felt to be used without a significant increase in water load on the wet web to the Yankee dryer.
In FIG. 3, the water/solids ratio of the wet web immediately after being pressed on the Yankee dryer is plotted against creped sheet caliper for a 15.5 lb/3000 sq ft dry sheet at a geometric mean tensile of 1000 g/3-inches. Use of the imprinting felt increases the sheet caliper by about 20%. Without a polymer treatment or without vacuum and the polytetrofluoroethylene (Teflon®) treatment, use of the imprinting felt increases sheet caliper but also increases the water/solids ratio of the web on the Yankee dryer by about 30%. With the polyurethane treatment and without vacuum, the sheet's caliper is still increased by about 20% and the water/solids ratio of the web on the Yankee is increased by about 20%. With either polymer treatment or the application of vacuum, the sheet's caliper is still increased by about 20% and the water/solids ratio of the web on the Yankee is increased by 10% or less.
FIG. 3 shows that using polymer treated imprinting felts can increase sheet bulk by about 20% with only a slight increase in water load of the web on the Yankee dryer. The process of the present invention provides an increase in bulk of the resultant sheet without a significant decrease in production rate.
FIG. 4 shows sheet absorbency in terms of grams of water absorbed per gram of solids versus wet geometric mean tensile for a paper produced by pressing with a conventional press felt and imprinting felts with different polymer treatments. This figure illustrates that sheet absorbency can be increased by as much as 25% when pressing the sheet with an imprinting felt compared to pressing the sheet with a conventional felt. As illustrated in this figure, the use of the polymer treatments on the imprinting felt significantly increases the absorbency of paper product produced therewith. Paper produced with an untreated imprinting felt has only slightly more absorbency than paper produced with a conventional felt; whereas, paper produced with a polymer treated imprinting felt has significantly higher absorbency than paper produced with either an untreated imprinting felt or paper produced with a conventional felt.
FIG. 5 shows the effect of the polymer treatments and vacuum on water/solids ratio and sheet absorbency of the web. The absorbency in this figure is given for a 15.5 lb/3000 sq ft sheet and a wet geometric mean tensile of 300 g/3-in. This figure illustrates that the use of the polymer treatments and vacuum can produce a sheet with a significant improvement in absorbency without significantly increasing the water/solids ratio of the web on the Yankee dryer. Using the untreated imprinting felt only slightly increased sheet absorbency over conventional pressing felt.
At low levels of batting, it is more difficult to entangle the batting with itself and the underlying base-imprinting fabric. At sheet side batting levels of 150 g/m 2 or less the sheet side batting is not as securely bonded to the base fabric as at higher batting levels. This loose batting tends to entangle with the paper fibers. These entangled paper fibers produce weak spots in the paper web as it is pressed on the Yankee dryer. This results in an unacceptable product. The use of a polymer treatment with an imprinting felt that has a low level of batting helps to secure the batting fibers together and to the base fabric. This allows the use of a felt with very low batting levels without the wet paper fibers entangling with loose batting fibers. In addition to securing low levels of sheet side batting to the base fabric, the use of the polymer treatment enables using press felts with low sheet side batting levels to effectively dewater the paper web during pressing on the Yankee dryer.
FIG. 6 is a photomicrograph of a cross section of a paper sheet produced with a conventional press felt. FIG. 7 is a photomicrograph of a cross section of a paper sheet produced with one of the improved imprinting felts of the present invention coated with polyurethane. As can be readily seen in these photomicrographs, the use of the improved imprinting felt produces a more open sheet structure. The imprinting felt creates numerous voids within the sheet. These voids result in a very open and absorbent paper.
The use of the polymer treatments allows the batting level of the felt to be reduced to a level where the sheet properties are optimized without an unacceptable increase in water load to the Yankee dryer.
The following examples are not to be construed as limiting the invention as described herein.
EXAMPLES
Examples of the use of the polymer-treated imprinting felts are given below.
The examples describe trials on both Fourdrinier and Crescent Forming paper machines. The Fourdrinier machine is described in reference to FIG. 1, above. A Crescent former and some of the differences between a Crescent former and Fourdrinier machine are set forth below.
The major difference between a Fourdrinier machine and Crescent former is that in the Fourdrinier machine the paper web is formed on a forming wire and transferred, after formation, to the pressing felt, while in a Crescent former the sheet is formed between a wire and a felt and leaves the forming section on the felt. Therefore, as opposed to the Fourdrinier machine, with the Crescent former there is no sheet transfer to the pressing felt. After the sheet is on the pressing felt, both types of machine press the sheet onto the Yankee dryer in substantially similar manners.
EXAMPLE 1
On a pilot machine as depicted in FIG. 1, a polytetrafluoroethylene treated imprinting felt was used to make a highly absorbent paper. The machine conditions were as follows:
______________________________________Type: Fourdrinier with Yankee dryerSpeed: 100 ft/minImprinting Felt Width 14 inchesImprinting Felt Length 19.5 ft______________________________________
The base fabric, used for the imprinting felt, was a 750 g/m 2 triple layer nylon woven fabric with about 100 g/m 2 of 20 micron in diameter nylon batting applied to both sides of the base fabric. The basic fabric was woven to create a prominent knuckle in the CD (cross-direction) with the CD strands going over 2 MD strands and then under 2 MD (machine-direction) strands. The base fabric had a CD strand count on the sheet side of 19 per inch. This fabric was saturated with a water dispersion of sub-micron polytetrafluoroethylene (Teflon®) particles and air dried. The total weight of Teflon® added was about 87 g/m 2 .
This fabric was run on the Fourdrinier machine with a furnish containing 70% Northern Hardwood Kraft fiber and 30% Northern Softwood Kraft fiber. To determine the effect of this fabric on paper sheet properties and productivity, a control fabric was also run. The control fabric was a conventional felt with high batting levels and no polymer treatment.
To achieve good sheet dewatering during pressing on the Yankee dryer 52, the treated imprinting felt was conditioned by passing the imprinting felt with the wet paper sheet attached over a vacuum dewatering box 30 or 34. The paper sheet solids were measured after pressing the wet sheet on the hot Yankee dryer 52.
After drying on the Yankee 52, the sheet were creped off the Yankee. The physical properties of the creped sheets are shown below.
TABLE 1______________________________________ TreatedProperty Control Imprinting Felt______________________________________Basis Weight lb/3000 sq ft 15.1 14.7MD dry tensile g/3-inch 1,774 1,831CD dry tensile g/3-inch 892 737MD wet tensile g/3-inch 485 500CD wet tensile g/3-inch 205 183Caliper mils/8-sheets 50.75 54.9Water Absorption g water/g solids 4.3 5.0Hot Yankee Solids % solids 36.3 36.5______________________________________
As shown in the above Table 1, the treated imprinting felt substantially increases both water absorption and bulk without a decrease in productivity or a significant loss in paper strength.
EXAMPLE 2
On a pilot machine, a polyurethane treated imprinting felt was used to make a highly absorbent paper. The base fabric and batting levels were the same as Example 1, with the sheet side treated with about 70 g/m 2 polyurethane. The furnish and machine conditions are the same as those described in Example 1.
The properties of the paper produced with this treated imprinting felt and those produced with the control felt are listed below.
TABLE 2______________________________________ TreatedProperty Control Imprinting Felt______________________________________Basis Weight lb/3000 sq ft 15.1 15.76MD dry tensile g/3-inch 1,774 1,663CD dry tensile g/3-inch 892 779MD wet tensile g/3-inch 485 550CD wet tensile g/3-inch 205 173Caliper mils/8-sheets 50.75 65.6Water Absorption g water/g solids 4.3 5.5Hot Yankee Solids % solids 36.3 35.9______________________________________
As shown in the above Table 2, the treated imprinting felt substantially increases both water absorption and bulk without a decrease in productivity or a significant loss in paper strength.
EXAMPLE 3
On a Crescent Former pilot machine, a polyurethane treated imprinting fabric was used to make a highly absorbent paper. The machine conditions were as follows:
______________________________________Type: Crescent Former with Yankee dryerSpeed: 1800 ft/minImprinting Felt Width 32 inchesImprinting Felt Length 146 ft______________________________________
The following is a description of the treated imprinting felt.
The base fabric was similar to that described in Example 1 with about 100 g/m 2 of 20 micron in diameter batting nylon batting applied to the sheet side of the fabric and about 300 g/m 2 applied to the machine side. The base fabric was woven to create a prominent knuckle in the CD direction with the CD strands going over 2 MD strands and then under 2 MD strands. The base fabric had a CD strand count on the sheet side of 19 per inch. This fabric was treated on the sheet side with polyurethane in a manner similar to that described in Example 2.
This fabric was run on the Crescent Former machine with a furnish containing 70% Northern Hardwood Kraft fiber and 30% Northern Softwood Kraft fiber. To determine the effect of this fabric on paper sheet properties and productivity, a control fabric was also run. Because of felt conditioning before sheet formation and because of a suction pressure roll at the felt-Yankee nip, it was not necessary to further condition the felt with the wet sheet attached as was done in Examples 1 and 2.
After drying on the Yankee dryer, the sheets were creped off. Both the control and treated imprinting felt provided adequate dewater and there was no need to decrease machine speed for the treated felt. The physical properties of the creped sheets are shown below.
TABLE 3______________________________________At a target weight of 15.3 lb/3000 sq ft Treated Control Imprinting FeltProperty (I) (I)______________________________________Basis Weight lb/3000 sq ft 15.6 15.5(air dried)MD dry tensile g/3-inch 2600 2035CD dry tensile g/3-inch 1454 1218MD wet tensile g/3-inch 819 572CD wet tensile g/3-inch 377 296Caliper mils/8-sheets 42.6 53.8Water Absorption g water/g solids 4.12 5.13______________________________________
TABLE 4______________________________________At a target weight of 16.8 lb/3000 sq ft Treated Control Imprinting FeltProperty (II) (II)______________________________________Basis Weight lb/3000 sq ft 17.1 17.3(air dried)MD dry tensile g/3-inch 1863 1803CD dry tensile g/3-inch 1101 1024MD wet tensile g/3-inch 512 573CD wet tensile g/3-inch 262 257Caliper mils/8-sheets 52.6 54.3Water Absorption g water/g solids 4.77 4.82______________________________________
As shown in the above Tables 3 and 4, using the treated imprinting felt increases both water absorption and bulk in the resultant paper sheet without a substantial decrease in productivity or a significant reduction in strength.
EXAMPLE 4
The base sheets produced in Ex. 3 were converted to 29 and 32 lb/3000 sq ft. two-ply paper products. The converting process consisted of embossing the base sheets, applying glue, and marrying the base sheets into a two-ply product.
TABLE 5______________________________________ Treated Control Imprinting FeltProperty (II) (I)______________________________________Basis Weight lb/3000 sq ft 32.1 29.2(air dried)MD dry tensile g/3-inch 3306 3519CD dry tensile g/3-inch 1580 1605MD wet tensile g/3-inch 959 1228CD wet tensile g/3-inch 419 443Caliper mils/8-sheets 154 157Water Absorption g water/sq 274 268meter______________________________________
The above data on the converted paper shows that the use of the treated imprinting felt allows the basis weight of the two-ply product to be reduced without a substantial loss in physical properties.
Other embodiments of the invention will be apparent to those skilled in the art from consideration of the specification and practice of the invention disclosed herein. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the invention being indicated by the following claims. | The felt disclosed is a base fabric which is covered with a low level of batting and which is treated with a polymer. A papermaking machine and method of using the machine which employs a felt that simultaneously imprints and dewaters a wet paper web as the web is deposited on a cylindrical drying surface. | 3 |
BACKGROUND
This invention is directed to a quick cooling cryostat which employs Simon cooling in cooperation with Joule Thomson cooling.
Simon cooling occurs in a high pressure gas tank when gas is discharged from the tank. The remaining gas in the tank does work on the gas being expelled, to decrease the temperature of the gas remaining in the tank. R. W. Stuart, U.S. Pat. No. 3,593,537 describes a Simon cooler.
A Joule Thomson cooler is one where a pre-cooled gas is expanded out of a nozzle at the cold point and the cold exhaust gas passes over the incoming higher pressure gas to provide the precooling. An example of a Joule Thomson cryostat is shown in J. S. Buller et al., U.S. Pat. No. 3,640,091.
In the prior art, high pressure gas bottles have been used to supply refrigerant gas to a Joule Thomson cryostat, as in Wurtz U.S. Pat. No. 3,095,711, but the advantage of employing both cooling methods in combination only occurs for quick cooldown situations where the structures are close-coupled.
SUMMARY
In order to aid in the understanding of this invention it can be stated in essentially summary form that it is directed to a quick cooling cryostat which comprises a high pressure refrigerant gas supply bottle directly connected to a Joule Thomson cryostat, with means for maximizing Simon cooling, such as insulation to separate the high pressure gas in the Simon vessel from large thermal masses.
It is thus an object of this invention to provide a quick cooling cryostat which attains operating temperature more quickly, by employing Simon cooling at the input of the Joule Thomson cryostat. It is a further object to provide a Simon cooling tank which has an interior of low thermal mass, to enhance Simon cooling. It is a further object to directly couple the Simon cooler tank together with a Joule Thomson cryostat inside of the same insulation envelope. It is yet another object to provide a valve which restrains the pressure in the Simon cooling tank until cooldown is needed, and then permits Simon cooled gas to flow directly into the cryostat.
Other objects and advantages of this invention will become apparent from the study of the following portion of the specification, the claims and the attached drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a longitudinal section through a quick cooling cryostat embodying my invention.
FIG. 2 is a longitudinal section through another quick cooling cryostat embodying my invention.
FIG. 3 is an enlarged partial section, with parts broken away, through one embodiment of a valve which can be used in the quick cooling cryostat.
FIG. 4 is a longitudinal section through another such valve.
FIG. 5 is a longitudinal section through yet another such valve.
DESCRIPTION
The quick cooling cryostat of this invention is generally indicated at 10 in FIG. 1. It comprises a Joule Thomson coldfinger 12 supplied from a Simon expansion tank 14. Insulation is provided, and preferably both of them are mounted within Dewar 16.
Joule Thomson coldfinger 12 comprises a finned tube 18 wound on mandrel 20. The coiled finned tube fits within housing 22 so that out flowing exhaust gas flows among the fins on tube 18. Exhaust 24, from the warm end of the coldfinger is directed to atmosphere, which provides the lowest practical convenient exhaust pressure.
Finned tube 18 has an inlet 26 at the warmer end and an outlet 28 at the cold end. The outlet acts as a nozzle in the final Joule Thomson expansion. The cold gas expanding from the outlet nozzle 28, which may contain some liquid depending upon the refrigerant gas, temperatures, pressures and heat loads, is directed for the closest thermal communication with device 30 to be cooled. Coldfinger 12 and device 30 are protected by a suitable insulation, preferably against both radiant and conductive heat. Conventionally this comprises Dewar 16. When device 30 requires optical access, window 32, of suitable optical properties can permit the optical access. In many cases, the device 30 is an infrared sensitive device and thus window 32 and other optics are suitably transparent thereto.
Simon expansion tank 14 is a high pressure tank which contains refrigerant gas under high pressure. Its outlet is connected through valve 34 to the inlet 26 of the Joule Thomson coldfinger. When valve 34 is opened, the pressurized gas in the tank does work in expelling gas from the tank into inlet 26. In doing so the gas in tank 14 drops in temperature, in some cases to the liquifaction temperature. Success in liquifying the gas or substantially reducing its temperature to inlet 26 is dependent upon the initial pressure and temperature of the tank and the gas, the thermal mass of the tank and heat transfer characteristics of the tank. The ideal situation is a very strong tank with zero thermal mass. The thermal mass and thermal diffusivity of the tank walls are the limiting factors in the advantage gained by using the tank as a source of rapidly cooling gas into the Joule Thomson coldfinger part of the cryostat. For these reasons, insulation 36 is provided on the interior of the Simon expansion tank 14. Tank 14 can be of metallic construction, but in such case must have interior insulation for maximum advantage. However, even an uninsulated metal tank has some advantage because of the short time of the cooldown and use. One construction by which tank 14 can have a maximum strength and minimized thermal mass is by employing a wound fiberglass epoxy structure. Simon expansion tank 14 may be internally or externally mounted of Dewar 16, but the connection to the inlet 26 must be as short as possible in order to achieve maximum results and minimize the thermal mass which is subjected to the Simon expansion cooling.
Before cooling is initiated, Simon expansion tank 14 contains refrigerant gas under high pressure. Particular gases in which may be employed include Freon 14, oxygen, argon, or nitrogen. Initial pressure is in the order of 10,000 psi. Upon release of the refrigerant gas from the expansion tank through the Joule Thomson coil, and its expansion out of outlet 28, cooldown from about 300°K ambient to an operating temperature of about 100°K is achieved within less than two seconds. The volume and pressure of tank 14 and the flow rate from outlet 28 are scaled so that blowdown is completed and the end of the need for cooling occurs in about 30 seconds. With such a short blowdown time the thermal mass of the Simon expansion tank, particularly with interior insulation, does not substantially decrease the effectiveness of the Simon cooling. Even without insulation, with such a short cooling time, only the inner tank skin is cooled.
One more specific example of the invention has a 1 inch diameter spherical tank charged with argon to 10,000 psi to produce an initial flow rate of 50 standard liters per minute in a small Joule-Thomson cryostat. If the Simon effect is not utilized the cooldown time for a 75 Joule thermal mass and one watt steady state heat load with an ideal cryostat would be on the order of 2.2 seconds and the running time 15 seconds. Utilization of the Simon effect decreases the cooldown time to 1.4 seconds and extends the operating time to 30 seconds. In addition to the improvements realized in the ideal case, which are on the order of 50 percent, is the real improvement derived by lowering the temperature gradient across the Joule-Thomson cryostat heat exchanger which increases heat exchanger efficiency and provides a closer approach to ideal performance.
In FIG. 1, valve 34 can be placed between the Simon expansion tank and the coiled tube of the Joule Thomson coldfinger. In this way, the pressure is restrained in the tank. On the other hand, valve 38 can be placed at the outlet 28 of the Joule Thomson coiled tube, and with valve 34 eliminated, the pressure is restrained in the coiled tube and the expansion tank. In this way, with the start of blowdown by the opening of valve 38, the expansion of the pressurized gas within finned tube 18 first results in a Simon cooling, rather than the heating associated with compression of the gas within the tubing. Thus, a slightly smaller volume of Simon expansion tank 14 is possible for the same cooling effect, and cooldown time is reduced.
Valve 40 of FIG. 3 or valve 42 of FIG. 4 are useful in the position of valve 38. FIG. 5 illustrates the valve 34 in the line between the expansion tank and coldfinger tubing. Valve 40 comprises a plug 44 in the open end of tube 28, and sealed therein by any high pressure sealant such as solder 46. The structure is such that when mechanically actuated, plug 44 can be separated from the sealant to release the gas.
In FIG. 4, sealant 48 is electrically conductive and fusible. It contains wire 50 so that an electric pulse between wire 50 metal and tubing outlet 28 causes melting of sealant 48 with its consequent pressure blowout. The sealant 48 can be indium or lead-tin solder, in which case the wire 50 is selected to withstand high temperature. On the other hand, the sealant 48 can be an electrically conductive epoxy which is thermoset in place to provide the necessary pressure sealing. The conductive epoxy used was Epoxy Products Incorporated "E-Solder No. 3022" which has an electrical resistivity of 0.01 OHM-CH. This is approximately 600 times the resistance of eutectic lead-tin solder, and therefore is heated to a greater degree. In such a case, an electrical pulse between wire 50 and metal tube outlet 28 causes destruction of the epoxy sufficient to have the pressure blow it out. Epoxy is the preferred material.
In the valve of FIG. 5, sealant plug 52 can be the same materials as the sealant 48. Wire 54 passes through the sealant plug and is externally electrically connected through connector 56. An electrical pulse between connector 56 and metal tube 26 melts or degrades the sealant 52 to a point where it blows out.
Quick cooling cryostat 60 illustrated in FIG. 2 has the same Dewar 62 and Joule Thomson coldfinger 64. The difference is that mandrel 66 on which the finned tube 68 is wound also serves as the Simon expansion tank 70. Valve 72 or 74 is provided to control the blowdown of the Simon expansion tank through the Joule Thomson coiled tube coldfinger. The thermal mass of expansion tank 70 is large with a respect to the cooling achieved by Simon expansion, and thus interior insulation 76 minimizes the loss of the Simon cooling into the thermal mass of the Simon expansion tank. For this reason, the Simon expansion is not employed to provide heat exchange cooling through the tank walls to the Joule Thomson coldfinger coils. The result is a simpler construction when the mandrel is of sufficient volume to provide the correct amount of Joule Thomson cooling and to provide the correct volume of gas for the cooling rate and blowdown time required. The same operating materials and criteria are applicable to cryostat 60 as are applicable to cryostat 10.
This invention having been described in its preferred embodiment, is clear that it is susceptible in numerous modifications and the embodiments within the ability of those skilled in the art and without the exercise of the inventive faculty. Accordingly, the scope of this invention is defined by the scope of the following claims. | A high pressure gas tank has its output closely connected to the input of a Joule Thomson cryostat. When the tank is permitted to discharge its gas, Simon cooling of the inlet gas to the cryostat decreases the time to cool down at the cold point in the cryostat. | 8 |
BACKGROUND OF THE INVENTION
This invention relates to vacuum pumps and more particularly to those pumps known as molecular drag pumps.
Molecular drag pumps operate on the general principle that, at low pressures, gas molecules striking a fast moving surface can be given a velocity component from the moving surface. As a result, the molecules tend to take up the same direction of motion as the surface against which they strike, thus urging the molecules through the pump leaving a relatively higher pressure in the vicinity of the pump exhaust.
Types of vacuum pump using the molecular drag mode of operation include "Holweck" pumps in which a helical gas path is defined between two co-axial hollow cylinders of different diameters by means of a helical thread mounted on the inner surface of the outer cylinder or on the outer surface of the smaller diameter cylinder and substantially occupying the space therebetween.
In such Holweck pumps, one cylinder is rotated at high speed about its longitudinal axis and gas present at one end of the helix is urged to move along the helical gas path between the cylinder by means of a molecular drag effect caused by impingement of the gas molecules on the spinning cylinder surface adjacent the gas path; a pumping effect can therefore be established.
Generally in the case of molecular drag pumps, the speeds of rotation of the cylinder are high, for example up to twenty thousand revolutions/minute or more.
The present invention is concerned with an improved pump design which in general utilises a helical member but which generally exhibits higher pumping efficiencies.
SUMMARY OF THE INVENTION
In accordance with the invention, there is provided a vacuum pump assembly which comprises at least two cylinders of different diameters and arranged coaxially relative to each other to define an annular space therebetween and a helical member positioned within the space to define a helical path between the cylinders wherein means are provided to effect rotation of the cylinders relative to the helical member, or vice versa, about their longitudinal axis.
The larger diameter cylinder clearly needs to be hollow to accommodate the one of smaller diameter; preferably the smaller one is hollow also to minimise weight.
Although both the helical member and the cylinders may be rotated, it is usual for only the cylinders or only the helical member to be rotated to effect the relative rotation therebetween.
In preferred embodiments, it is the cylinders which are rotated about a stationary helical member.
The velocity of rotation in all cases can be from ten thousand revolutions per minute up to thirty thousand revolutions per minute or more.
In the case of rotating cylinders, it is usual for them both to rotate at the same velocity and, preferably, they can both be mounted on the same rotor assembly. The cylinders must rotate in the same direction.
In contrast to the known Holweck design in which there is relative movement between the helical component and one cylinder wall surface, the invention provides for relative movement between the helical member and two cylinder wall surfaces, thereby leading to a higher net gas velocity and therefore higher compression through the helix; a higher overall efficiency is thereby achieved.
The cylinders themselves, especially when adapted for rotation can usefully be made from their metal sheet, for example steel or aluminium, or from plastic material or from fibre reinforced material.
One or both "cylinders" may have a tapered cross-section and therefore be more properly described as conical or frusto-conical. All such "cylinders" are, however, included herein in the basic term of cylinder.
In the case of tapered cross-section "cylinders", it is preferably for the annular space cross-section to be larger at the helical gas path inlet and smaller at the outlet to aid pumping efficiency.
In preferred embodiments, the apparatus comprises three or more cylinders, all of which are arranged co-axially with an annular space being defined between adjacent cylinders and a helical member being positioned in each annular space to define a helical path between adjacent cylinders. In such embodiments in particular, it is very preferably for the cylinders to be adapted for rotation and the helical members to be stationary.
In the case of apparatus in which the cylinders are adapted for rotation and irrespective of the number of cylinders present, the apparatus may advantageously possess a helical thread positioned on a pump body component (similar to that of a conventional Holweck design) such that it defines a further helical path between the body component and the outer surface of the outermost cylinder.
With regard to the helical member, this needs to be present in the pump apparatus independently of the cylinders with which it is associated but whose structure is sufficiently close to the relevant walls of each cylinder that the necessary helical gas path is defined therebetween.
There may be only one such gas path but, in order to aid gas throughput and generally to aid pumping efficiency, the helical member preferably defines more than one, for example four, six or eight, gas paths in parallel with each other. In such cases in particular, each gas path can usefully extend for only part of a turn of the "helix" and in reality be regarded simply as part-helical (or arcuate) paths rather than full helical paths.
In preferred embodiments, the pitch of the helix varies along the length of the helical member and is more at the pump inlet than at the pump outlet, i.e. the angle of the helical member component defining a helical path in relation to a plane normal to the longitudinal axis is greater at the inlet to that at the outlet, for example is about 30° at the inlet and is only 15° at the outlet and changes gradually between those angles therebetween.
Two or more stages of pump assembly as described above may be employed in the same vacuum pump. In such cases the subsequent stage(s) may be mounted on the same rotor or on a separate rotor, preferably the former.
Pump assemblies of the invention may be used as "stand alone" vacuum pumps or may usefully be used in conjunction with other pump mechanisms in the same pump body or with separate pumps.
For example, an inlet impeller can be added across the inlet to the helical path(s) to assist in urging the gas molecules through the inlet, especially during molecular flow, and thereby increase pumping speed. Such an impeller could be very similar to the top stage of a turbomolecular pump and comprise co-planar, circular arrays of blades adapted for rotation with the main pump rotor (cylinders or helical member), preferably at the same speed as the main pump rotor and advantageously mounted on the same rotor.
As a further example, conventional Holweck or Siegbahn stages may be used at the pump assembly outlet to increase the net compression ratio.
An added stage at the outlet could also be a regenerative stage or stages in which, in particular, blades mounted on a flat surface or surfaces or on the peripheral edge of a rotating disc urge gas molecules through passageways defined about the volumes associated with the rotating blades. The use of such a regenerative stage can generally allow the pump as a whole to exhaust directly to atmospheric pressure.
BRIEF DESCRIPTION OF THE DRAWINGS
For a better understanding of the invention, reference will now be made, by way of exemplification only, to the accompanying drawings in which:
FIG. 1 is a schematic, sectional representation of a vacuum pump assembly of the invention employing two rotating cylinders.
FIG. 2 is a schematic representation of a helical member of the assembly shown in FIG. 1.
FIG. 3 is a schematic sectional representation of a vacuum pump assembly of the invention employing three rotating cylinders.
FIG. 4 is a schematic sectional representation of a vacuum pump assembly of the invention employing a conical "cylinder".
FIG. 5 is a schematic sectional representation of a vacuum pump assembly of the invention employing a standard Holweck helical component on the pump body.
FIG. 6 is a schematic sectional representation of a vacuum pump assembly of the invention employing an impeller at the inlet.
FIG. 7 is a schematic representation of a further helical member for use with an assembly of the invention.
DETAILED DESCRIPTION
With reference to the drawings, FIG. 1 shows a vacuum pump assembly of the invention in its simplest form. It comprises a pump body 1 within which is mounted for rotation therein about its longitudinal axis a shaft 2 to the upper end (as shown) of which is attached a circular disc 3.
The disc 3 supports at their lower ends (as shown) two hollow cylinders 4,5 arranged co-axially relative to each other. The cylinders 4,5 are fixed to the disc 3 in a manner which allows them to retain their cylindrical shape during rotation at high speed of the disc/cylinders combination.
The cylinders 4,5 define an annular space 6 therebetween within which is positioned a stationary helical member 7 of a shape shown (not to scale) in FIG. 2. The helical member 7 has eight individual part-helical gas paths therethrough defined by the walls of the cylinders 4,5 and the individual helical member components 8,9,10,11,12,13,14,15. The spacing between the cylinder walls and the helical member components is as small as possible without incurring any direct contact therebetween in use.
A support ring 16 of the helical member forms part of the top of the pump body 1 as does a further support ring 17. The helical member also has a lower support ring 18.
The helical member is therefore positioned in the pump body 1 relative to the cylinders 4,5 in the manner shown in FIG. 1 with the individual inlets to the part helical gas paths being aligned with the top of the pump body.
In use of the pump assembly the shaft 2 is caused to rotate at, for example, thirty thousand revolutions per minute by motor means (not shown) thereby causing rotation of both cylinders 4,5 at the same speed. Gas molecules are drawn in to the part helical gas paths in the direction shown by the arrows `A` and urged through the gas paths in the manner described above to exit the helical member at eight individual outlets and through exhaust apertures in the disc 3 to connect to a pump assembly outlet (not shown) in the direction of the arrows `B`.
Turning to FIG. 3, there is shown a pump assembly of the same basic type as that shown in FIG. 1 but with three rotatable hollow cylinders 101,102,103 within which are positioned two helical members 104,105.
The helical members 104,105 are of the same type of structure to that shown in FIG. 2 but each of the passageways defined therein by means of helical member components and the adjacent walls of two of the three cylinders.
As with the assembly shown in FIG. 1, the cylinders are fixed at their base (as shown) to a disc 106 which is itself mounted on a shaft 107 adapted within a pump body 108 for rotation at high speed.
The helical members are held in position within the top of the pump body and supported therein in the same manner as with the assembly of FIG. 1.
The pump assembly of FIG. 3 therefore possesses individual inlets associated with each of the two helical members; the gas flow being indicated by arrows A and B.
FIG. 4 shows the same type of pump assembly as that shown in FIG. 1 except for the use of a hollow tapered cylinder 201 (as the inner of two cylinders) and corresponding shaped helical member 202.
The mounting of the cylinder 201 on a disc 203 attached to a shaft 204 and the support of the helical member 202 within a top portion of a pump body 205 is all essentially the same to that described with reference to the assembly of FIG. 1.
An advantage of the use of a tapered cylinder is that the part-helical gas passageway defined between the cylinder 201 and the outer cylinder 206 and the helical member 201 is broader at the inlet than at the outlet and therefore a greater gas throughput is possible together with a greater compression ratio of gas passing between the arrows `A` and the arrows `B`.
FIG. 5 also shows a pump assembly as the same basic type as that shown in FIG. 1 but with the addition of a `Holweck` helical thread 301 on the inside surface of the cylindrical pump body 302.
Again the mounting of two cylinders 303,304 on a disc 305 which is itself attached to a shaft 306 and the positioning of a helical member 307 between the cylinders and held within a top portion of the pump body 302 is essentially the same as the construction of the assembly of FIG. 1.
The presence of the Holweck stage in the form of the thread 301 (and its close positioning to the outside surface of the cylinder 304) again allows for a greater pump efficiency and greater gas throughput via the individual passageways defined by the helical member 307 (in the direction of Arrows `A` and `B`) and via the further passageway defined by the helical thread 301 (in the direction of the Arrows C and D).
FIG. 6 again shows a pump assembly of the same type as that shown in FIG. 1 but with the addition of an impeller 401 mounted on the top (as shown) of the inner of two cylinders 402,403 which are themselves both mounted on a disc 404 attached to a shaft 405 adapted for rotation at high speed within a pump body 406.
A helical member 407 is again present to define a part-helical pathway between the two cylinders 402,403 and is held in a top portion of the pump body 406 in a similar manner to that of FIG. 1.
The impeller 401 fits closely (without touching) within an upper extension of the pump body 406. The impeller is similar to the top stage of a turbo pump and comprises a co-planar circular array of blades.
Such an impeller is useful to assist in urging gas molecules in to the pump in the direction of the arrows `A` and `B`.
Finally, FIG. 7 shows a further helical member for use with an assembly of the invention. This comprises vertical stiffening members 501 linking the top and bottom of the helix and being attached to individual helical member 502. Such an arrangement allows in general the use of longer helical paths without causing the member as a whole to become too flexible. In this member, only an inner support ring 503 is employed with no external support ring equivalent to the ring 16 of the member shown in FIG. 2.
In the member shown in FIG. 7, there are the same number of vertical stiffening members 501 as there are individual helical members 502 (six of each). There may however be more or less of either depending on the required stiffness of the helical member as a whole.
In all types of pump assembly of the invention, it is preferred to rotate the shaft, and hence the cylinders at a speed of up to thirty thousand revolutions per minute or more. | A vacuum pump assembly which comprises at least two cylinders of different diameters and arranged coaxially relative to each other to define an annular space therebetween and a helical member positioned within the space to define a helical path between the cylinders. Rotation of the cylinders is effected relative to the helical member, or vice versa, about their longitudinal axis. | 5 |
CROSS REFERENCE TO A RELATED APPLICATION (S)
This application is a National Phase Patents Applications and claims priority to and benefit of International Application Number PCT/CN2010/080549, filed on Dec. 30,2010, which claims priority to and benefit of Chinese Patent Application Number 201010222446.0, filed on Jul. 9,2010, the entire disclosure of which are incorporated herein by reference.
TECHNICAL FIELD
The present invention relates to a microsphere containing an anti-tuberculosis drug and a vascular targeted embolic agent comprising the microsphere, particularly relates to a sustained-release microsphere with moxifloxacin as an anti-tuberculosis active ingredient and sodium alginate as a carrier for crosslinking and vascular targeted embolic agent thereof. The present invention also relates to a method for preparing the sustained-release microsphere, and use of the microsphere in preparing drugs for treating pulmonary tuberculosis, mass hemoptysis of pulmonary tuberculosis, pulmonary tuberculosis cavity, renal tuberculosis, thyroid tuberculosis, cervical lymph node tuberculosis, genital tuberculosis (fallopian tube tuberculosis, endometrium tuberculosis, testis tuberculosis, epididymis tuberculosis), pericardial tuberculosis, chest wall tuberculosis, pleural tuberculosis and other tuberculosises in the body through interventional embolization.
BACKGROUND TECHNOLOGIES
Tuberculosis is one of major infectious diseases seriously harming human life and health, and also becomes the number-one killer in infectious diseases and the leading cause of death for adults. In the late 1990s, due to drug-resistant bacteria and other issues, the tuberculosis which had disappeared made a comeback throughout the world, which increased difficulties in controlling the tuberculosis. The World Health Organization has made preliminary statistics showing that 1.9 billion people around the world are infected by tuberculosis bacilli, the number of patients with tuberculosis has been up to about 20 million, the number of new cases is up to 8 million each year, and 3 million people on average die from tuberculosis each year. In China, the number of patients infected by tuberculosis bacilli are also rising, and tuberculosis presents an upward trend, the number of patients with tuberculosis ranks the second in the world, and the number of deaths due to tuberculosis each year is about 150,000; prevention and treatment of tuberculosis is a major issue that needs to be resolved urgently, and therefore research and development of new anti-tuberculosis drugs and new dosage forms is imminent.
Mycobacterium tuberculosis mainly parasitizes in normal cells and has some resistance to drugs, and Mycobacterium tuberculosis can be killed only when concentration of an anti-tuberculosis drug in the cell reaches a certain level. Oral formulations of anti-tuberculosis drugs are often influenced by the first-pass effect firstly, and subjected to protein binding, metabolism, excretion, decomposition and other processes during circulating around the body, but only a small amount of drug can reach the target tissue, target organ and target cell, therefore, in order to improve concentration of the drug in the target area, dose of the drug must be increased, which enhances systemic toxic and side effects of the drug. Targeted formulations have characteristics such as directionally releasing drugs, increasing concentration of drugs in lesion sites and cells, improving efficacy, reducing toxic and side effects, therefore it is considered that the anti-tuberculosis drug targeted formulations have clinical application value and development prospects.
Moxifloxacin, which belongs to the fourth-generation chemically synthesized antibiotic drugs of fluoroquinolones, is a product launched by Bayer (Germany) in 1999. Moxifloxacin blocks replication of DNA by inhibiting activities of bacterial DNA gyrase A subunit and topoisomerase IV to play roles in killing bacteria. For gram-negative bacteria, moxifloxacin mainly inhibits the DNA gyrase, and for gram-positive bacteria, the primary action target is the topoisomerase IV. Chemical structure of moxifloxacin is characterized in that the methoxyl is introduced to the 8 th carbon atom, which increases the drug's capability of binding to the bacteria and capability of penetrating and destroying the cell membrane, and its post-antibiotic effect (PAE) is strong and lasting.
Moxifloxacin retains antibacterial activity and antibacterial spectrum of quinolone drugs on gram-negative bacteria, and the methoxyl at the 8 th carbon atom increases antibacterial activity and broadens antibacterial spectrum of moxifloxacin on gram-positive bacteria. Moxifloxacin is extremely effective to atypical pathogens such as mycoplasma pneumoniae, chlamydia, and legionella, and has strong activity on anaerobic bacteria, for example, it has significant antibacterial activity on anaerobic bacteria with or without spores. Moxifloxacin is also effective to bacteria which are resistant to antibiotics of β-lactams, macrolides, amino glycopeptides and tetracyclines. Moxifloxacin, different from the hepatic cytochrome P-450 isozyme inhibitor, has no drug cross-resistance with these antibiotic drugs, thus avoiding many potential interactions between drugs. Moxifloxacin has similar early bactericidal activity to isoniazid (INH) or rifampin, and has bactericidal activity for early and extended early stage of patients with pulmonary tuberculosis, which shows that moxifloxacin can well penetrate into the tuberculosis lesion sites and quickly kill the fast growing flora in the sputum of patients with severe cavitary pulmonary tuberculosis.
Since it is on the market, moxifloxacin has been widely applied clinically due to its advantages such as broad antibacterial spectrum, strong antibacterial power, wide distribution in the body, high drug concentration in the body, long half-life, good efficacy, little side effects, no drug cross-resistance with other antibacterial drugs, almost no photosensitive reactions and the like. With wide application of anti-tuberculosis drugs clinically, drug resistance of Mycobacterium tuberculosis gets higher and higher, especially the problem of multi-drug resistance, which has become a subject of concern for the anti-tuberculosis field, and is also a main factor impacting chemotherapy effect on tuberculosis. Therefore, selecting an appropriate dosage form of an anti-tuberculosis drug is important for the current treatment and control of tuberculosis.
Phenomenon of recurrence of tuberculosis and drug resistance of tuberculosis bacilli is becoming more and more serious, despite that there are complex causes for the occurrence of the phenomenon, a very important factor is long treatment course, making patients be unable to take medicine with full amount regularly till the end of treatment, which is a common problem faced in the treatment of tuberculosis in countries of the world. On the premise of ensuing therapeutic effect, the problem of drug compliance can be effectively resolved by reducing dose of a drug and prolonging intervals of administration. In order to obtain an anti-tuberculosis drug formulation which can play a long-lasting effect in human body, we have selected a natural polymer, sodium alginate, with good biocompatibility as a carrier and moxifloxacin as a model drug, to crosslink with an adsorbent, so as to obtain a vascular embolic agent containing sustained-release biodegradable microspheres by prescription selection, release experiments in vitro and studies in vivo.
There are only sporadic reports about study on microspheres carrying an anti-tuberculosis drug at home, most of drugs reported are drugs to be administered orally or by injection. At abroad, systematic study reports about microspheres carrying an anti-tuberculosis drug are mainly concentrated in study groups of America, Japan and India, involving different carriers, different drugs, different microsphere size and different routes of administration. Some scholars were dedicated to study on the anti-tuberculosis sustained-release system before, mainly involving oral agents, inhalants, injections, and subdermal implants.
Currently, clinical anti-tuberculosis drugs are mainly oral and injectable formulations, and the efficacy of the injectable formulation is not ideal. Application of anti-tuberculosis drugs is greatly limited since effective drug concentration cannot be obtained at the lesion site and significant systemic toxicity and drug resistance occur in the application process. A few therapies of embolism plus drug infusion have the following defects: the drug cannot be sustainedly released in a relatively uniform form, and the “shock wave” efficacy of the drug may cause necrosis or damage to local tissues when local drug infusion concentration is too high.
Anti-tuberculosis drug microsphere vascular embolic agent is a new dosage form, wherein microspheres deposit in the lung, which can delay release of the drug, protect the drug from being destroyed by enzyme hydrolysis, and prolong retention time of the drug in the lung, and also has advantages in low incidence rate of side effects, good toleration and safety. At present, there has been no reports at home and abroad about an anti-tuberculosis vascular embolic agent prepared by crosslinking moxifloxacin with sodium alginate and an adsorbent, and about application of the anti-tuberculosis vascular embolic agent in treating patients with pulmonary tuberculosis, mass hemoptysis of pulmonary tuberculosis, pulmonary tuberculosis cavity, bronchial stenosis of pulmonary tuberculosis, multi-drug resistant cavitary pulmonary tuberculosis, renal tuberculosis, thyroid tuberculosis, genital tuberculosis (fallopian tube tuberculosis, endometrium tuberculosis, testis tuberculosis, epididymis tuberculosis), cervical lymph node tuberculosis, pericardial tuberculosis, chest wall tuberculosis, and other tuberculosises of other parts in the whole body through interventional embolization.
Moxifloxacin belongs to the fourth-generation chemical antibiotic drugs of fluoroquinolones, with poor solubility in water and organic solvents. Oral and injectable formulations of moxifloxacin are usually applied clinically and have defects as follows: amount of oral absorption is small, dose of injection is low, an effective drug concentration cannot be obtained at the lesion site, releasing cannot be performed in a relatively uniform and sustained form, and adverse reactions are easily caused.
SUMMARY OF THE INVENTION
The present invention provides a sodium alginate crosslinked moxifloxacin sustained-release microsphere, wherein the microsphere comprises: a drug carrier, adsorbent, anti-tuberculosis drug active ingredient, strengthening agent and curing agent, the carrier is sodium alginate, the adsorbent is human serum albumin or bovine serum albumin, the anti-tuberculosis drug active ingredient is moxifloxacin, the strengthening agent is gelatin or hyaluronic acid, and the curing agent is a salt of divalent metal cation such as divalent calcium or barium salt.
In one embodiment, the sustained-release microsphere is preserved in a vegetable oil or liquid paraffin as a preservation solution, and the particle size of the microsphere is in the range of 50˜100 μm, 50˜150 μm, 50˜200 μm, 100˜300 μm, 150˜450 μm, 300˜500 μm, 500˜700 μm, 700˜900 μm or 900˜1,250 μm.
In another embodiment, the microspheres are made into dry powdered particles with particle size in the range of 10˜50 μm, 25˜50 μm, 50˜100 μm, 100˜350 μm, 300˜550 μm or 500˜750 μm.
In the sustained-release microsphere of the present invention, the weight ratio of sodium alginate and moxifloxacin is preferably 1˜75:0.25˜12.5.
The present invention also provides a method for preparing the above-mentioned sustained-release microsphere, which comprises the following steps:
1) dissolving sodium alginate with physiological saline or water for injection based on mass-volume percentage of 0.5-15% to obtained a sodium alginate solution, i.e., a carrier solution; 2) dissolving human serum albumin or bovine serum albumin with water for injection based on mass-volume percentage of 0.1-10% to obtain a albumin solution, i.e., an adsorbent; 3) grinding, stirring, dissolving and adsorbing moxifloxacin with the adsorbent prepared in step 2) to obtain a moxifloxacin solution, i.e., a drug solution, wherein moxifloxacin and the adsorbent are added in an amount of mass-volume percentage of 1.6-4%; 4) preparing an aqueous solution of 1-15% by mass-volume with a salt of divalent metal cation such as divalent calcium or barium salt to obtain a curing solution; wherein the calcium salt is preferably selected from calcium chloride and calcium lactate, the barium salt is preferably barium chloride; 5) adding anhydrous ethanol and water for injection into the resulting curing solution, wherein the volume ratio of the resulting curing solution, anhydrous ethanol and water for injection is 2:1:2, so that a curing solution containing anhydrous ethanol is obtained; 6) dissolving gelatin or hyaluronic acid with water for injection to obtain a gelatin or hyaluronic acid solution of 0.1-10% by mass-volume, i.e., a strengthening solution; 7) pooling the drug solution and the carrier solution at a volume ratio of 1:1˜30, and magnetically stirring the solution uniformly to obtain a preparing solution; 8) spraying the above-obtained preparing solution by a high voltage electrostatic multi-head microsphere generating device to obtain droplets which are then dispersed in the curing solution, and removing supernatant when precipitation is completed , to obtain sodium alginate crosslinked microspheres or micro-gel beads containing moxifloxacin; 9) adding the above-obtained microspheres or micro-gel beads into the strengthening solution, stirring the solution, and discarding supernatant to obtain microspheres or micro-gel beads containing drug, i.e., sodium alginate crosslinked moxifloxacin sustained-release microspheres.
In one embodiment, the sodium alginate crosslinked moxifloxacin sustained-release microspheres containing drug obtained in step 9) are preserved in vegetable oil or liquid paraffin oil as a preservation solution. The vegetable oil may be selected from soybean oil, tea oil, corn oil, rapeseed oil, cottonseed oil or other oils for injection.
Or, in another embodiment, the sodium alginate crosslinked moxifloxacin sustained-release microspheres are dried to obtain powered particles, i.e., dry spheres, for example, the method of freeze drying or oven drying is employed.
In one special embodiment, the high voltage electrostatic multi-head microsphere generating device used in step 8) comprises: a high voltage electrostatic generating device, propulsion pump, ejecting head, sterile container, a plurality of positive and negative electrodes, sterile syringes of various models, and lifting device, wherein the high voltage electrostatic generating device is provided with the plurality of positive and negative electrodes, the propulsion pump is connected to the sterile syringe and the ejecting head, the positive electrode is connected to the ejecting head, the negative electrode is connected to a stainless steel wire immersed in the curing solution, the stainless steel wire is connected to the sterile container, and the lifting device for adjusting distance is under the stainless steel wire and the sterile container.
When preparing microspheres with the preparing solution, a high electric field is generated between the positive and negative electrodes of every group after the high voltage electrostatic multi-head microsphere generating device is powered on, when the propulsion pump pushes out the mixed solution of sodium alginate and the adsorbed drug at a constant speed, the electric field force overcomes the inherent viscous force and surface tension of the sodium alginate solution and makes the drug-containing polymer solution disperse into droplets of a certain size which are ejected to the curing solution and crosslinked quickly into calcium alginate microspheres (micro-gel beads). In order to prevent the water-soluble drug from releasing too early, the micro-gel bead is coated with the gelatin solution in the present invention; and in order to prevent the releasing (leaking) of the water-soluble drug from microspheres during the preservation period, the present invention employs a vegetable oil (or liquid paraffin) for preservation, which forming a water-in-oil system, so that loss of the drug before application can be avoided; the present invention employs the technology of high voltage electrostatic preparing sphere (capsule) so that organic solvents can be avoided, which helps to improve stability of the drug, and the particle size of the microsphere (capsule) can be adjusted by adjustment of voltage, the operation is simple and convenient, and the operation condition is mild, the toxic organic solvents and glutaraldehyde used in the prior art can be avoided, and the product of the present invention is environmentally friendly.
The present invention prepares microspheres in the presence of the divalent metal cation (calcium or barium ion) by using sodium alginate as a drug carrier crosslinking agent, the anti-tuberculosis drug of moxifloxacin as a drug active ingredient, and albumin as an adsorbent to link moxifloxacin and sodium alginate, and then the microspheres are coated with gelatin, which resolves the problem of too fast releasing of the water-soluble drug; in terms of preservation, autoclaved vegetable oil or liquid paraffin is used to preserve the wet gel drug microspheres so that moxifloxacin is not released when it is not used. The present invention changes the dosage form and administration route of the moxifloxacin anti-tuberculosis drug so as to achieve effects of efficient, low toxicity, and achieve safe and effective clinical application.
In the present invention, the anti-tuberculosis drug of moxifloxacin and the adsorbent (human serum albumin or bovine serum albumin) are grinded and dissolved, and mixed in proportion, before combined together by adsorption, and then crosslinked by with the sodium alginate carrier; and the anti-tuberculosis drug of moxifloxacin is wrapped in the microspheres by the high voltage electrostatic multi-head microsphere generating device in the presence of the divalent metal cation (calcium or barium ion); in order to prevent the anti-tuberculosis drug of moxifloxacin from releasing to the preservation solution, the microsphere is further coated with gelatin which forms a thin membrane around the microsphere, and then put into the autoclaved vegetable oil or liquid paraffin to preserve wet gel drug microspheres, so that the sodium alginate microsphere vascular targeting embolic agent containing moxifloxacin is prepared.
The present invention further relates to a vascular targeted embolic agent containing the above-mentioned sodium alginate crosslinked moxifloxacin sustained-release microsphere.
The present invention further relates to a use of the above-mentioned sodium alginate crosslinked moxifloxacin sustained-release microsphere in preparing a vascular targeted embolic agent. Said vascular targeted embolic agent may be used for treating tuberculosis, for example, used for treating pulmonary tuberculosis, mass hemoptysis of pulmonary tuberculosis or pulmonary tuberculosis cavity through interventional embolization; used for treating renal tuberculosis, thyroid tuberculosis, cervical lymph node tuberculosis, pericardial tuberculosis, chest wall tuberculosis and/or pleural tuberculosis; and used for treating fallopian tube tuberculosis, endometrium tuberculosis, testis tuberculosis or epididymis tuberculosis.
BENEFICIAL EFFECTS
The present invention has the following advantages:
1. a high voltage electrostatic multi-head microsphere generating device produced industrially is selected, so that the drug microsphere vascular targeted embolic agent suitable for different clinical uses with controllable size can be produced; 2. a natural polymer material, with good biocompatibility, i.e. sodium alginate is select as a drug carrier, so that a vascular targeted embolic agent containing biodegradable sustained-release drug microspheres can be obtained; 3. human serum albumin or bovine serum albumin is selected as an adsorbent, so that the anti-tuberculosis drug of moxifloxacin can be absorbed well.
The formulation of the present invention can not only improve local drug concentration greatly, decrease concentration of the drug in the circulation system, reduce toxicity of the drug to normal tissues, but also facilitate application of the drug greatly, reduce courses of treatment, shorten time for treatment, and reduce drug complications, treatment costs for patient and drug tolerance. In the treatment with the formulation of the present invention, the method of interventional radiology or bronchoscopic intervention is employed to perform target organ artery angiography, then embolic microspheres are chosen after the diameter of the embolic microspheres are determined according to the findings shown in angiography, and treatment of embolizing the target organ is performed with the chosen embolic microsphere, especially embolizing the peripheral small artery blood vessel of the target organ. Treatment of embolizing the peripheral small artery blood vessel may be considered for the following patients with pulmonary tuberculosis or following conditions: (1) patients subjected to failure in initial treatment and retreatment by adoping anti-tuberculosis therapy whose smear test shows tuberculosis-positive after the course of retreatment and sputum culture shows that Mycobacterium tuberculosis is resistant to two or more HR anti-tuberculosis drugs, i.e., multiple-drug resistant; (2) patients with the following symptoms: there is a single thin-wall or caseous cavity with tuberculosis bacilli in the sputum being persistently positive, and no apparently active lesion is around the cavity or the lesion has been stable; (3) patients with single fiber cavity of pulmonary tuberculosis and no negative conversion of sputum bacillus occurring after long time of treatment; (4) bronchial tuberculosis patients with sputum bacilli being persistently positive after long time of treatment; (5) interventional embolization treatment for mass hemoptysis of pulmonary tuberculosis; (6) intervention treatment for tuberculosises other than pulmonary tuberculosis, such as, renal tuberculosis, thyroid tuberculosis, cervical lymph node tuberculosis, pericardial tuberculosis, chest wall tuberculosis, pleural tuberculosis and genital tuberculosis (fallopian tube tuberculosis, endometrium tuberculosis, testis tuberculosis, epididymis tuberculosis), or the like.
When the formulation of the present invention is used, a micro-catheter is preferably used to perform superselective embolization, the sterile operation is employed, and injection is performed slowly as required or slowly performed multiple times under fluoroscopy through the catheter until the flow rate of the contrast agent decreases significantly, and embolization is completed. Further artery angiography is performed to evaluate embolization effect. During application, if the sodium alginate microsphere vascular embolic agent containing the moxifloxacin anti-tuberculosis drug is powdered particles, dry spheres preserved in a sealed container are firstly dissolved in physiological saline to reconstituted to wet spheres, then an appropriate amount of contrast agent or diluted contrast agent is added and the mixture is mixed uniformly to make the microspheres fully suspended in the contrast agent, then under monitoring by an imaging equipment, the mixture is injected into the blood vessel at the lesion site slowly or injected slowly multiple times by catheter, so as to achieve a super-selective embolization until the flow rate of the contrast agent decreases obviously, and embolization is completed. Further artery angiography is performed and embolization effect is determined.
The outstanding advantages of the present invention are as follows: human serum albumin or bovine serum albumin used as an adsorbent are safe and effective, which successfully resolves the problem that moxifloxacin cannot dissolve in water or organic solvents completely, the difficult problem that when the combination of moxifloxacin and the albumin is mixed and crosslinked with water-soluble sodium alginate solution, the mixture is unsinkable, and the problem that drug microspheres cannot be formed when moxifloxacin reacts with other reagents and is wrapped under the action of positive and negative electric fields; size of anti-tuberculosis drug microspheres prepared is ideal and controllable, and the microsphere vascular embolic agent prepared has characteristics of high drug loading, long retention time in the body and high bioavailability, adjustable drug releasing rate, being capable of achieving targeted delivery of the drug, and target specificity, and can be used to treat pulmonary tuberculosis, mass hemoptysis of pulmonary tuberculosis, pulmonary tuberculosis cavity, renal tuberculosis, thyroid tuberculosis, cervical lymph node tuberculosis, genital tuberculosis (fallopian tube tuberculosis, endometrium tuberculosis, testis tuberculosis, epididymis tuberculosis), pericardial tuberculosis, chest wall tuberculosis, pleural tuberculosis and other tuberculosises in the body through interventional embolization.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present invention will be further illustrated in combination with embodiments, and it should be understood that the preferred embodiments described herein are only used to illustrate and explain the present invention, rather than limit the present invention.
Example 1
Preparation of Sodium Alginate Crosslinked Moxifloxacin Anti-Tuberculosis Microsphere Vascular Embolic Agent
1. Treatment of glassware:
The cleaned glassware was dried out in the air and then placed and baked in the high-temperature oven (for sterilization and depyrogenation) to be used.
2. Selection of Microsphere Preparing Device:
A high voltage electrostatic multi-head microsphere generating device, which can controllably prepare spheres with uniform size, is simple and convenient to operate, has high output, and easily implements mass production, was selected.
3. Method for Preparing Various Reagents: (1) Preparation of sodium alginate solution:
8 g of sodium alginate was weighed and placed in a glassware, then 500 ml of physiological saline or water for injection was added into the glassware while stirring, magnetical stirring was performed until all the sodium alginate was dissolved to obtain a sodium alginate solution;
(2) Preparation of adsorbent:
Human serum albumin (or bovine serum albumin) was dissolved with water for injection at a ratio of 0.1˜10% (mass-volume percentage) to obtain an albumin solution, i.e., an adsorbent;
(3) Preparation of moxifloxacin solution:
12 g of commercially available moxifloxacin was weighed, placed in a glassware, and dissolved with 50 ml of the human serum albumin or bovine serum albumin solution of 0.1˜10% (mass-volume percentage) by stirring to obtain a moxifloxacin solution;
(4) Preparation of gelatin strengthening solution:
30 g of gelatin was placed in a glassware, 500 ml of physiological saline or water for injection was added into the glassware while stirring, magnetical stirring was performed until all the gelatin were dissolved to obtain a gelatin strengthening solution;
(5) Preparation of curing solution containing anhydrous ethanol:
200 g of calcium chloride or barium chloride or calcium lactate was weighed and placed in a glassware, 4,000 ml of water for injection was added into the glassware while stirring, magnetical stirring was performed until the calcium compound was dissolved, and then 1,000 ml of anhydrous ethanol was added to obtain a curing solution containing anhydrous ethanol;
(6) Preparation of preservation solution:
The purchased soybean oil (or tea oil, corn oil, peanut oil, rapeseed oil, cottonseed oil or other oils for injection) or liquid paraffin for injection was used as a preservation solution;
(7) Preparation of mixed solution:
The sodium alginate solution and the moxifloxacin solution prepared above were mixed and stirred uniformly to obtain a mixed solution.
4. Preparation of microspheres:
The above-obtained mixed solution was aspirated by a sterile syringe, and dripped into the above-obtained curing solution through the high voltage electrostatic multi-head microsphere liquid drop generating device, microspheres or micro-gel beads with different particle size ranges were prepared as required, and the resulting sodium alginate crosslinked moxifloxacin microspheres or micro-gel beads sank into the bottom of the container.
The high voltage electrostatic multi-head microsphere generating device comprises: a high voltage electrostatic generating device, propulsion pump, ejecting head, sterile container, positive and negative electrodes, sterile syringes of various models, and a lifting device. The high voltage electrostatic multi-head generating device has two electrodes of positive and negative electrodes in every group, the propulsion pump is connected to the sterile syringe and the ejecting head, the positive electrode is connected to the ejecting head, the negative electrode is connected to the stainless steel wire immersed in the curing solution, and the stainless steel wire is connected to the sterile container, and the lifting device for adjusting distance is under the stainless steel wire and the sterile container.
Particle sizes of said microspheres or micro-gel beads preserved in the preservation solution are as follows: 50˜100 μm, 50˜150 μm, 50˜200 μm, 100˜300 μm, 150˜450 μm, 300˜500 μm, 500˜700 μm, 700˜900 μm or 900˜1,250 μm. After the upper layer of the solution in the above-mentioned container was decanted, the microspheres or micro-gel beads were washed with physiological saline for immediate use.
The upper layer solution of the above-obtained microspheres was decanted, and the resulting sodium alginate microspheres containing the moxifloxacin anti-tuberculosis drug was dried (the method of freeze drying or oven drying was used to prepare dry spheres) to obtain powdered particles; the particle sizes of the powdered particles are in the range of 10˜50 μm, 25˜50 μm, 50˜100 μm, 100˜350 μm, 300˜550 μm or 500˜750 μm; the powdered particles were sealed for preservation, and before use, the powdered particles were soaked with physiological saline for a few minutes to be reconstituted to wet spheres.
Patients with pulmonary tuberculosis were treated by the method of interventional radiology or bronchoscopic intervention, wherein a catheter was inserted into the opening of target organ segment, a guide wire was introduced under monitoring by X-ray, and artery angiography was performed when the catheter was embedded into the blood vessel lumen. According to the findings shown in angiography, continuous photographs confirmed that the front end of the catheter was fixed, the guide wire was exited, and the catheter was retained, and the appropriate particle size range was selected for the above-mentioned sodium alginate crosslinked moxifloxacin microspheres; the sodium alginate crosslinked moxifloxacin microspheres (wet spheres) were washed with physiological saline for three times, generally 500˜700 μm microspheres can produce better effect, then an appropriate amount of contrast agent was added and mixed uniformly, the mixture was slowly injected into the lesion site via the catheter under fluoroscopy until the flow rate of the contrast agent decreased significantly, and then embolization was completed. Further artery angiography was performed to evaluate embolization effect.
Example 2
Preparation of Sodium Alginate Crosslinked Moxifloxacin Anti-Tuberculosis Microsphere Vascular Embolic Agent
1. Treatment of glassware:
The cleaned glassware was dried out in the air and then placed and baked in the high-temperature oven (for sterilization and depyrogenation) to be used.
2. Selection of microsphere preparing device:
A high voltage electrostatic multi-head microsphere generating device, which can controllably prepare spheres with uniform size, is simple and convenient to operate, has high output, and easily implements mass production, was selected.
3. Method for preparing various reagents: (1) Preparation of sodium alginate solution:
10 g of sodium alginate was weighed and placed in a glassware, then 500 ml of physiological saline or water for injection was added into the glassware while stirring, magnetical stirring was performed until all the sodium alginate was dissolved to obtain a sodium alginate solution;
(2) Preparation of adsorbent:
Human serum albumin (or bovine serum albumin) was dissolved with water for injection at a ratio of 0.1˜10% (mass-volume percentage) to obtain an adsorbent, i.e., an albumin solution;
(3) Preparation of moxifloxacin anti-tuberculosis drug solution:
14 g of commercially available moxifloxacin was weighed, placed in a glassware, and dissolved with 50 ml of the human serum albumin or bovine serum albumin solution of 0.1˜10% (mass-volume percentage) by stirring to obtain a moxifloxacin anti-tuberculosis drug solution;
(4) Preparation of gelatin strengthening solution:
26 g of gelatin was placed in a glassware, 500 ml of physiological saline or water for injection was added into the glassware while stirring, magnetical stirring was performed until all the gelatin was dissolved to obtain a gelatin strengthening solution;
(5) Preparation of curing solution containing anhydrous ethanol:
200 g of calcium chloride or barium chloride or calcium lactate was weighed and placed in a glassware, and 4,000 ml of water for injection was added into the glassware while stirring, magnetical stirring was performed until the calcium compound was dissolved, and then 1,000 ml of anhydrous ethanol was added to obtain a curing solution containing anhydrous ethanol;
(6) Preparation of preservation solution:
The purchased soybean oil (or tea oil, corn oil, peanut oil, rapeseed oil, cottonseed oil or other oils for injection) or liquid paraffin for injection was used as a preservation solution;
(7) Preparation of mixed solution:
The sodium alginate solution and moxifloxacin anti-tuberculosis drug solution prepared above were mixed and stirred uniformly to obtain a mixed solution.
4. Preparation of microspheres:
The above-obtained mixed solution was aspirated by a sterile syringe, and dripped into the above-obtained curing solution through the high voltage electrostatic multi-head microsphere liquid drop generating device, microspheres or micro-gel beads within different particle size ranges were prepared as required, and the resulting sodium alginate crosslinked moxifloxacin microspheres or micro-gel beads sank into the bottom of the container.
The high voltage electrostatic multi-head microsphere generating device comprises: a high voltage electrostatic generating device, propulsion pump, ejecting head, sterile container, positive and negative electrodes, sterile syringes of various models, and a lifting device. The high voltage electrostatic multi-head generating device has two electrodes of positive and negative electrodes in every group, the propulsion pump is connected to the sterile syringe and the ejecting head, the positive electrode is connected to the ejecting head, the negative electrode is connected to the stainless steel wire immersed in the curing solution, and the stainless steel wire is connected to the sterile container, and the lifting device for adjusting distance is under the stainless steel wire and the sterile container.
Particle sizes of said microspheres or micro-gel beads preserved in the preservation solution are as follows: 50˜100 μm, 50˜150 μm, 50˜200 μm, 100˜300 μm, 150˜450 μm, 300˜500 μm, 500˜700 μm, 700˜900 μm or 900˜1,250 μm. After the upper layer of the solution in the above-mentioned container was decanted, the microspheres or micro-gel beads were washed with physiological saline for immediate use.
The upper layer solution of the above-obtained microspheres was decanted, and the resulting sodium alginate microspheres containing the moxifloxacin anti-tuberculosis drug was dried (the method of freeze drying or oven drying was used to prepare dry spheres) to obtain powdered particles; the particle sizes of the powdered particles are in the range of 10˜50 μm, 25˜50 μm or 50˜100 μm; 100˜350 μm, 300˜550 μm or 500˜750 μm; the powdered particles were sealed for preservation, and before use, the powdered particles were soaked with physiological saline for a few minutes to be reconstituted to wet spheres.
Patients with pulmonary tuberculosis cavity were treated by the method of interventional radiology or bronchoscopic intervention, wherein a catheter was inserted into the opening of target organ segment, a guide wire was introduced under monitoring by X-ray, and artery angiography was performed when the catheter was embedded into the blood vessel lumen. According to the findings shown in angiography, continuous photographs confirmed that the front end of the catheter was fixed, the guide wire was exited, and the catheter was retained, and the appropriate particle size range was selected for the above-mentioned sodium alginate crosslinked moxifloxacin microspheres; the sodium alginate crosslinked moxifloxacin microspheres (wet spheres) were washed with physiological saline for three times, generally 700˜900 μm microspheres can produce better effect, then an appropriate amount of contrast agent was added and mixed uniformly, the mixture was slowly injected into the lesion site via the catheter under fluoroscopy until the flow rate of the contrast agent decreased significantly, and then embolization was completed. Further artery angiography was performed to evaluate embolization effect.
Results of clinical trials show that the drug microspheres of the present invention can be used for embolizing peripheral small artery blood vessel, after embolization, no pressure difference is generated between two ends of potential collateral circulation blood vessels, it is not easy to form a secondary collateral circulation, and the drug can be delivered to the target organs and target cells; when applied, the drug can be highly concentrated in the lesion site, and only minimal amount of drug exist in the normal site, the therapeutic effect is improved and the systemic toxic and side effect is reduced, primary blood supply to sites of tuberculosis is effectively cut off, the flushing action of blood flow on the drug is blocked, and the duration of action of the drug is extended, so that the therapeutic purpose can be achieved.
Example 3
Preparation of Sodium Alginate Crosslinked Moxifloxacin Anti-Tuberculosis Microsphere Vascular Embolic Agent
1. Treatment of glassware:
The cleaned glassware was dried out in the air and then placed and baked in the high-temperature oven (for sterilization and depyrogenation) to be used.
2. Selection of microsphere preparing device:
A high voltage electrostatic multi-head microsphere generating device, which can controllably prepare spheres with uniform size, is simple and convenient to operate, has high output, and easily implements mass production, was selected.
3. Method for preparing various reagents: (1) Preparation of sodium alginate solution:
15 g of sodium alginate was weighed and placed in a glassware, then 500 ml of physiological saline or water for injection was added into the glassware while stirring, magnetical stirring was performed until all the sodium alginate was dissolved to obtain a sodium alginate solution;
(2) Preparation of adsorbent:
Human serum albumin (or bovine serum albumin) was dissolved with water for injection at a ratio of 0.1˜10% (mass-volume percentage) to obtain an adsorbent, i.e., an albumin solution;
(3) Preparation of moxifloxacin anti-tuberculosis drug solution:
10 g of commercially available moxifloxacin was weighed, placed in a glassware, and dissolved with 50 ml of the human serum albumin or bovine serum albumin solution of 0.1˜10% (mass-volume percentage) by stirring to obtain a moxifloxacin anti-tuberculosis drug solution;
(4) Preparation of gelatin strengthening solution:
20 g of gelatin was placed in a glassware, 500 ml of physiological saline or water for injection was added into the glassware while stirring, magnetical stirring was performed until all the gelatin was dissolved to obtain a gelatin strengthening solution;
(5) Preparation of curing solution containing anhydrous ethanol:
200 g of calcium chloride or barium chloride or calcium lactate was weighed and placed in a glassware, and 4,000 ml of water for injection was added into the glassware while stirring, magnetical stirring was performed until the calcium compound was dissolved, and then 1,000 ml of anhydrous ethanol was added to obtain a curing solution containing anhydrous ethanol;
(6) Preparation of preservation solution:
The purchased soybean oil (or tea oil, corn oil, peanut oil, rapeseed oil, cottonseed oil or other oils for injection) or liquid paraffin for injection was used as a preservation solution;
(7) Preparation of mixed solution:
The sodium alginate solution and moxifloxacin anti-tuberculosis drug solution prepared above were mixed and stirred uniformly to obtain a mixed solution.
4. Preparation of microspheres
The above-obtained mixed solution was aspirated by a sterile syringe, and dripped into the above-obtained curing solution through the high voltage electrostatic multi-head microsphere liquid drop generating device, microspheres or micro-gel beads within different particle size ranges were prepared as required, and the resulting sodium alginate crosslinked moxifloxacin microspheres or micro-gel beads sank into the bottom of the container.
The high voltage electrostatic multi-head microsphere generating device comprises: a high voltage electrostatic generating device, propulsion pump, ejecting head, sterile container, positive and negative electrodes, sterile syringes of various models, and a lifting device. The high voltage electrostatic multi-head generating device has two electrodes of positive and negative electrodes in every group, the propulsion pump is connected to the sterile syringe and the ejecting head, the positive electrode is connected to the ejecting head, the negative electrode is connected to the stainless steel wire immersed in the curing solution, and the stainless steel wire is connected to the sterile container, and the lifting device for adjusting distance is under the stainless steel wire and the sterile container.
Particle sizes of said microspheres or micro-gel beads preserved in the preservation solution are as follows: 50˜100 μm, 50˜150 μm, 50˜200 μm, 100˜300 μm, 150˜450 μm, 300˜500 μm, 500˜700 μm, 700˜900 μm or 900˜1,250 μm. After the upper layer of the solution in the above-mentioned container was decanted, the microspheres or micro-gel beads were washed with physiological saline for immediate use.
The upper layer solution of the above-obtained microspheres was decanted, and the resulting sodium alginate microspheres containing the moxifloxacin anti-tuberculosis drug was dried (the method of freeze drying or oven drying was used to prepare dry spheres) to obtain powdered particles; the particle sizes of the powdered particles are in the range of 10˜50 μm, 25˜50 μm or 50˜100 μm; 100˜350 μm, 300˜550 μm or 500˜750 μm; the powdered particles were sealed for preservation, and before use, the powdered particles were soaked with physiological saline for a few minutes to be reconstituted to wet spheres.
Patients with mass hemoptysis of pulmonary tuberculosis were treated by the method of interventional radiology or bronchoscopic intervention, wherein a catheter was inserted into the feeding artery in the target organ, and artery angiography was performed. According to the findings shown in angiography, the appropriate particle size range was selected for the above-mentioned sodium alginate microspheres containing moxifloxacin. The sodium alginate crosslinked moxifloxacin microspheres (wet spheres) were washed with physiological saline for three times, generally 500˜700 μm or 700˜900 μm microspheres can produce better effect, then an appropriate amount of contrast agent was added and mixed uniformly, the mixture was slowly injected into the lesion site via the catheter under fluoroscopy until the flow rate of the contrast agent decreased significantly, and then embolization was completed. Further artery angiography was performed to evaluate embolization effect.
Results of clinical trials show that the solvent used in the present invention is effective and safe, when the catheter is inserted into the target blood vessel, microspheres containing the drug is mixed with the contrast agent by a syringe after angiography, and when the mixture of the microspheres and contrast agent is slowly injected into the catheter, no aggregation occurs and no catheters is blocked. Particle sizes of said drug microspheres are appropriate (generally 500˜700 μm or 700˜900 μm microspheres can produce better effect), and the drug microspheres have advantages such as, having good biocompatibility, being nontoxic and harmless to human bodies, and non-immunogenic, having affinity with the drug carried, low drug toxic and side effects, high drug concentration and high utilization.
Example 4
Preparation of Sodium Alginate Crosslinked Moxifloxacin Anti-Tuberculosis Microsphere Vascular Embolic Agent
1. Treatment of glassware:
The cleaned glassware was dried out in the air, and then placed and baked in the high-temperature oven (for sterilization and depyrogenation) to be used.
2. Selection of microsphere preparing device:
A high voltage electrostatic multi-head microsphere generating device, which can controllably prepare spheres with uniform size, is simple and convenient to operate, has high output, and easily implements mass production, was selected.
3. Method for preparing various reagents: (1) Preparation of sodium alginate solution:
20 g of sodium alginate was weighed and placed in a glassware, then 500 ml of physiological saline or water for injection was added into the glassware while stirring, magnetical stirring was performed until all the sodium alginate was dissolved to obtain a sodium alginate solution;
(2) Preparation of adsorbent:
Human serum albumin (or bovine serum albumin) was dissolved with water for injection at a ratio of 0.1˜10% (mass-volume percentage) to obtain an adsorbent, i.e., an albumin solution;
(3) Preparation of moxifloxacin anti-tuberculosis drug solution:
22 g of commercially available moxifloxacin was weighed, placed in a glassware, and dissolved with 50 ml of the human serum albumin or bovine serum albumin solution of 0.1˜10% (mass-volume percentage) by stirring to obtain a moxifloxacin anti-tuberculosis drug solution;
(4) Preparation of gelatin strengthening solution:
22 g of gelatin was placed in a glassware, 500 ml of physiological saline or water for injection was added into the glassware while stirring, magnetical stirring was performed until all the gelatin was dissolved to obtain a gelatin strengthening solution;
(5) Preparation of curing solution containing anhydrous ethanol:
200 g of calcium chloride or barium chloride or calcium lactate was weighed and placed in a glassware, and 4,000 ml of water for injection was added into the glassware while stirring, magnetical stirring was performed until the calcium compound was dissolved, and then 1,000 ml of anhydrous ethanol was added to obtain a curing solution containing anhydrous ethanol;
(6) Preparation of preservation solution:
The purchased soybean oil (or tea oil, corn oil, peanut oil, rapeseed oil, cottonseed oil or other oils for injection) or liquid paraffin for injection was used as a preservation solution;
(7) Preparation of mixed solution:
The sodium alginate solution and moxifloxacin anti-tuberculosis drug solution prepared above were mixed and stirred uniformly to obtain a mixed solution.
4. Preparation of microspheres:
The above-obtained mixed solution was aspirated by a sterile syringe, and dripped into the above-obtained curing solution through the high voltage electrostatic multi-head microsphere liquid drop generating device, microspheres or micro-gel beads within different particle size ranges were prepared as required, and the resulting sodium alginate crosslinked moxifloxacin microspheres or micro-gel beads sank into the bottom of the container.
The high voltage electrostatic multi-head microsphere generating device comprises: a high voltage electrostatic generating device, propulsion pump, ejecting head, sterile container, positive and negative electrodes, sterile syringes of various models, and a lifting device. The high voltage electrostatic multi-head generating device has two electrodes of positive and negative electrodes in every group, the propulsion pump is connected to the sterile syringe and the ejecting head, the positive electrode is connected to the ejecting head, the negative electrode is connected to the stainless steel wire immersed in the curing solution, and the stainless steel wire is connected to the sterile container, and the lifting device for adjusting distance is under the stainless steel wire and the sterile container.
Particle sizes of said microspheres or micro-gel beads preserved in the preservation solution are as follows: 50˜100 μm, 50˜150 μm, 50˜200 μm, 100˜300 μm, 150˜450 μm, 300˜500 μm, 500˜700 μm, 700˜900 μm or 900˜1,250 μm. After the upper layer of the solution in the above-mentioned container was decanted, the microspheres or micro-gel beads were washed with physiological saline for immediate use.
The upper layer solution of the above-obtained microspheres obtained above was decanted, and the resulting sodium alginate microspheres containing the moxifloxacin anti-tuberculosis drug was dried (the method of freeze drying or oven drying was used to prepare dry spheres) to obtain powdered particles; the particle sizes of the powdered particles are in the range of 10˜50 μm, 25˜50 μm or 50˜100 μm; 100˜350 μm, 300˜550 μm or 500˜750 μm; the powdered particles were sealed for preservation, and before use, the powdered particles were soaked with physiological saline for a few minutes to be reconstituted to wet spheres.
The method of interventional radiology or bronchoscopic intervention is used to treat patients with tuberculosis other than pulmonary tuberculosis, such as renal tuberculosis, thyroid tuberculosis, cervical lymph node tuberculosis, genital tuberculosis (fallopian tube tuberculosis, endometrium tuberculosis, testis tuberculosis, epididymis tuberculosis), pericardial tuberculosis, chest wall tuberculosis, pleural tuberculosis and other tuberculosises in the body.
A catheter was inserted into the feeding artery in the target organ, and artery angiography was performed. According to the findings shown in angiography, the appropriate particle size range was selected for the above-mentioned sodium alginate microspheres containing moxifloxacin. The sodium alginate crosslinked moxifloxacin microspheres (wet spheres) were washed with physiological saline for three times, generally 300˜500 μm microspheres can produce better effect, then an appropriate amount of contrast agent was added and mixed uniformly, the mixture was slowly injected into the lesion site via the catheter under fluoroscopy until the flow rate of the contrast agent decreased significantly, and then embolization was completed. Further artery angiography was performed to evaluate embolization effect. Results of clinical trials show that the solvent used in the present invention is effective and safe, local concentration of the drug is increased while the total amount of drug is decreased, the incidence of systemic toxic and side effect is reduced; when the biodegradable microspheres containing the drug is implanted into the tuberculosis, the release rate of the drug can approach zero-order release rate, stable drug concentration can be maintained, no burst releasing effect is produced, and it is not necessary to remove microspheres by operation.
Those skilled in the art can understand that the description hereinbefore are only preferred embodiments of the present invention and not intended to limit the present invention. Although the present invention is illustrated in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions of the foregoing embodiments or perform equivalent substitution on part of the technical features. Any modifications, equivalent substitutions, improvements and the like made within the spirit and principle of the present invention shall be included within the protection scope of the present invention. | A sodium alginate crosslinked slow-released moxifloxacin microsphere, the preparation method of the microsphere, a vascular target embolus containing the microsphere and the use of the microsphere in preparing the vascular target embolus. The microsphere contains moxifloxacin, a drug carrier, a adsorbent, a reinforcing agent and a solidifying agent, wherein the drug carrier is sodium alginate, the adsorbent is albumin prepared from human plasma or bovine serum albumin, the reinforcing agent is gelatin or hyaluronic acid, and the solidifying agent is a divalent metal cation chosen from calcium salt or barium salt. | 0 |
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application claims priority from U.S. Provisional Application No. 61/513,829 filed on Aug. 1, 2011, which is incorporated by reference in its entirety herein.
TECHNICAL FIELD
[0002] The invention is directed to methods and systems for prioritizing and allocating bandwidth in a mobile network, and for devices to respond to provider rules about prioritizing and allocating bandwidth.
BACKGROUND
[0003] As with any other communication medium, mobile data networks continue to evolve, achieving increasingly faster speeds. In practice, however, although maximum theoretical throughput climbs, the total bandwidth is divided across an ever-increasing number of connected devices, often leading to an overall net loss in terms of overall performance. With bandwidth-intensive activities such as video streaming and teleconferencing gaining popularity, available bandwidth may be allocated arbitrarily, often yielding an inconsistent end-user experience.
[0004] Various quality of service systems exist, control mechanisms which can reserve, prioritize and allocate resources based on any specific set of arbitrary criteria. These mechanisms can include traffic shaping, scheduling algorithms, congestion avoidance and other techniques, each offering its own unique advantages, disadvantages and overall effects on bandwidth. But while quality of service can yield certain performance gains, some of its major limitations stem from its lack of interaction with end-point devices.
[0005] Specifically, with current quality of service systems, it is impossible for applications running on connected mobile devices to accurately detect what portion of available bandwidth is being allocated to them, whether this bandwidth is being treated or otherwise manipulated, and whether the throughput will remain consistent throughout the duration of the operation in question. This unfortunate restriction makes it nearly impossible for all but the most advanced application algorithms to properly cope with varying differences in throughput, which creates interruptions which are often visible and disruptive to the end-user. For example, users attempting to stream video on congested networks will often see pauses as the application repopulates the buffer.
[0006] It would be desirable to address or improve some of these problems by improving communication between devices and infrastructure service providers.
SUMMARY
[0007] By promoting transparency of the service provider restrictions and requirements, it is believed that this would allow devices and their applications to better tailor requests and thus benefit from an increased probability of valid and fulfillable bandwidth requests.
[0008] This would also reduce performance issues by only allowing valid and pre-screened requests that take into account bandwidth availability forecasts. It is a goal to use devices to provide signals to distribute traffic better, so it's possible to ask for the right thing based on traffic conditions.
[0009] Devices can also provide feedback to help service provider manage traffic (by supplying localized data from the devices). Although the invention is fundamentally device-centric, the impact is at a network-level. The idea is to expand this data set to the whole network, based on the collected data from many devices that are providing feedback into the network. Further, this will allow developers to build a better app ecosystem and a better network by providing hooks at a network level, and getting everyone else to adopt these beneficial standards.
[0010] According to a first aspect of the invention, a method is provided for adaptively acquiring bandwidth on a mobile device given traffic prioritization and bandwidth allocation rules of an infrastructure service provider. The device submits a first bandwidth query to the service provider, including a first content type and a first bandwidth requirement estimate. Information is retrieved from the service provider as to its traffic prioritization and bandwidth allocation rules and limitations relevant to the first query. This information is then made available to an application on the device, which provides a response. In light of the response, a second bandwidth query is submitted to the service provider, including a request for bandwidth based on the information. Provided this second bandwidth query is valid, bandwidth is obtained for the application on the device according to the request.
[0011] The device may further provide congestion, latency or other localized condition data to the service provider. This data may, for example, be provided in the course of the first bandwidth query or the second bandwidth query. The location of the device may also be specified to assist the service provider in mapping local conditions with feedback from many devices.
[0012] The device may further run a speed test as to the connection speed. The speed test data can then be returned to the service provider. The speed test may be run following the first bandwidth query. Alternatively, or in addition, the speed test may be run and reported to the service provider at intervals, irrespective of the first and second bandwidth queries.
[0013] The second bandwidth query may include a second content type, downgraded from the first content type, in response to the information from the service provider. The second bandwidth query may also (or in addition) include a second bandwidth requirement estimate, downgraded from the first bandwidth requirement estimate, in response to the information from the service provider. For example, the second bandwidth query may include a modified content type or bandwidth requirement estimate if the information from the service provider suggests that the connection or performance would be poor.
[0014] The second bandwidth query may be formulated to express the request according to rules of the service provider. For example, the second bandwidth query can be formulated to express the request for first-come-first-served bandwidth if accepted by the service provider according to the information. Alternatively, the second bandwidth query may be formulated to express the request for type-specific bandwidth if within a proportion accepted by the service provider according to the information.
[0015] Input from the user may be sought prior to submitting the second bandwidth query.
[0016] According to a second aspect of the invention, a method is provided for adaptively acquiring bandwidth on a mobile device given traffic prioritization and bandwidth allocation rules of an infrastructure service provider. The device runs at least one speed test to evaluate bandwidth available for a prospective bandwidth use by an application on the device and generates speed test data. Based on the device application response to that speed test data, a bandwidth query is submitted to an infrastructure service provider, including a request for bandwidth. The speed test data and location of the device are also submitted to the service provider. Provided the query is valid according to traffic prioritization and bandwidth allocation rules of the service provider, bandwidth is obtained for the application on the device according to the request.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] FIG. 1 is a visual representation of the interactive quality of service system in a cellular coverage area.
[0018] FIG. 2 is a flow diagram illustrating the process to determine traffic prioritization and bandwidth allocation.
DETAILED DESCRIPTION
[0019] This system defines an interactive quality of service method, in which the infrastructure providing and managing the available bandwidth does not run completely independently of connected devices. This contrasts with traditional methods where devices would request bandwidth blindly since service provider restrictions were generally only detectable after the fact. In the present case, service providers can passively or actively communicate with these clients, providing details as to what sort of line quality and consistency can be expected for a given time segment, and receiving feedback from client devices as well.
[0020] For example, such feedback may include latency and throughput, location and cell tower data, etc. These may be calculated by the device and sent as sample data sets.
[0021] Thus the network may find that there is only congestion in a certain area (e.g. downtown) while the rest of the network is steady, so it may start rerouting some of the downtown traffic to ease the congestion.
[0022] Before embodiments of the invention are explained in detail, it is to be understood that the invention is not limited in its application to the details of the examples set forth in the following descriptions or illustrated drawings. The invention is capable of other embodiments and of being practiced or carried out for a variety of applications and in various ways. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting.
[0023] It should also be noted that the invention is not limited to any particular software language described or implied in the figures and that a variety of alternative software languages may be used for implementation of the invention.
[0024] Many components and items are illustrated and described as if they were hardware elements, as is common practice within the art. However, one of ordinary skill in the art, and based on a reading of this detailed description, would understand that, in at least one embodiment, the components comprised in the method and tool are actually implemented in software.
[0025] As will be appreciated by one skilled in the art, the present invention may be embodied as a system, method or computer program product. Accordingly, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment (including firmware, resident software, micro-code, etc.) or an embodiment combining software and hardware aspects that may all generally be referred to herein as a “circuit,” “module” or “system.” Furthermore, the present invention may take the form of a computer program product embodied in any tangible medium of expression having computer usable program code embodied in the medium.
[0026] Computer program code for carrying out operations of the present invention may be written in any combination of one or more programming languages, including an object oriented programming language such as Java, Smalltalk, C++ or the like and conventional procedural programming languages, such as the “C” programming language or similar programming languages. Computer code may also be written in dynamic programming languages that describe a class of high-level programming languages that execute at runtime many common behaviors that other programming languages might perform during compilation. JavaScript, PHP, Perl, Python and Ruby are examples of dynamic languages. Additionally computer code may also be written using a web programming stack of software, which may mainly be comprised of open source software, usually containing an operating system, Web server, database server, and programming language. LAMP (Linux, Apache, MySQL and PHP) is an example of a well-known open-source Web development platform. Other examples of environments and frameworks in which computer code may also be generated are Ruby on Rails which is based on the Ruby programming language, or node.js which is an event-driven server-side JavaScript environment.
[0027] The program code may execute entirely on the client device, partly on the client device, as a stand-alone software package, partly on the client device and partly on a remote computer or entirely on the remote computer or server. In the latter scenario, the remote computer may be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or the connection may be made to an external computer (for example, through the Internet using an Internet Service Provider).
[0028] A device that enables a user to engage with an application using the invention, including a memory for storing a control program and data, and a processor (CPU) for executing the control program and for managing the data, which includes user data resident in the memory and includes buffered content. The computer may be coupled to a video display such as a television, monitor, or other type of visual display while other devices may have it incorporated in them (iPad). An application or a game or other simulation may be stored on a storage media such as a DVD, a CD, flash memory, USB memory or other type of memory media or it may be downloaded from the Internet. The storage media can be inserted to the console where it is read. The console can then read program instructions stored on the storage media and present a user interface to the user.
[0029] In some embodiments, the device is portable. In some embodiments, the device has a display with a graphical user interface (GUI), one or more processors, memory and one or more modules, programs or sets of instructions stored in the memory for performing multiple functions.
[0030] It should be understood that although the term application has been used as an example in this disclosure in essence the term may also apply to any other piece of software code where the embodiments of the invention are incorporated. The software application can be implemented in a standalone configuration or in combination with other software programs and is not limited to any particular operating system or programming paradigm described here. Thus, this invention intends to cover all applications and user interactions described above as well as those obvious to the ones skilled in the art.
[0031] The computer program comprises: a computer usable medium having computer usable program code, the computer usable program code comprises: computer usable program code for presenting graphically to the users options for scrolling via the touch-screen interface.
[0032] Several exemplary embodiments/implementations of the invention have been included in this disclosure. There may be other methods obvious to persons skilled in the art, and the intent is to cover all such scenarios. The application is not limited to the cited examples, but the intent is to cover all such areas that may be benefit from this invention.
[0033] The device may include but is not limited to a personal computer (PC), which may include but not limited to a home PC, corporate PC, a Server, a laptop, a Netbook, a Mac, a cellular phone, a Smartphone, a PDA, an iPhone, an iPad, an iPod, an iPad, a PVR, a set-top box, wireless enabled Blu-ray player, a TV, a SmartTV, wireless enabled Internet radio, e-book readers e.g. Kindle or Kindle DX, Nook, etc. and other such devices that may be used for the viewing and consumption of content whether the content is local, is generated on demand, is downloaded from a remote server where it exists already or is generated as a result. Client devices and server devices (or systems) may be running any number of different operating systems as diverse as Microsoft Windows family, MacOS, iOS, any variation of Google Android, any variation of Linux or Unix, PalmOS, Symbian OS, Ubuntu or such operating systems used for such devices available in the market today or the ones that will become available as a result of the advancements made in such industries.
[0034] The present invention makes use of multiple queries or handshakes to define a fulfillable bandwidth request. Bandwidth availability is forecasted in light of these queries. The mobile device's operating system can then share this data with a running application as it sees fit. Practically, this will allow end-user applications to internally adjust their settings in order to accommodate the expected line conditions, ensuring a smoother and consistent user experience. For example, a video streaming application which receives an unfavorable prognosis for bandwidth will be able to compensate by lowering the bitrate or resolution to better accommodate the available throughput.
[0035] Developers are given access to check the network conditions to preemptively select the appropriate type of feed or data access (i.e. don't access high resolution streams when the traffic is too heavy). This type of access and gatekeeping can also help enforce and track usage in a more fine-grained way given that there is a handshake process for both finding out the current network conditions and accessing the network.
[0036] Referring to FIG. 1 , a hypothetical scenario is depicted in which a number of mobile devices 2 , 3 , 4 are connected to an infrastructure component 1 providing bandwidth.
[0037] Devices constantly receive feedback from the infrastructure component at regular, configurable intervals or key events. Key events may include starting an application on the client device that requires bandwidth usage.
[0038] Again referring to FIG. 1 , the following sample scenario is provided. The first device 2 queries the infrastructure component 1 (i.e. service provider or related entity), which indicates that sufficient bandwidth is available for the type of application(s) it is running.
[0039] This device 2 subsequently proceeds with its operation normally. A second device 3 queries the infrastructure component 1 , which once again indicates that sufficient bandwidth is available for application(s) it is running. This device 3 subsequently proceeds with its operation normally. A third device 4 queries the infrastructure component 1 . However, the infrastructure component 1 is now in a congested state due to the demands of the connected devices 2 , 3 , and indicates that only limited bandwidth is available. This device 4 adjusts its settings to accommodate this reduced throughput and proceeds with its operation. During subsequent queries, device 4 receives indication from infrastructure component 1 that additional bandwidth is now available.
[0040] The device 4 now adjusts its bandwidth consuming applications to use the optimal maximum available.
[0041] In the absence of any other demands, available bandwidth is allocated on a first come, first serve basis. As the network becomes more congested, heuristics are applied that distribute bandwidth according to configurable criteria which may include: prioritization of certain user accounts, such as for public emergency services; the degree to which first come, first serve is applied, as opposed to the absolute equalization of bandwidth; and the bandwidth permitted for any given content or MIME-type. Information is made available to the infrastructure component 1 through queries, including but not limited to, bandwidth capacity and signal quality, such as in −dBm units, from the perspective of any given connected device. Conditions are preferably signalled to the device through the network level. The OS is preferably able to modify any network requests to have a priority that the network can process.
[0042] In an embodiment, queries from devices to the infrastructure consist of Internet content-type or MIME type (such as video, music, images, text) and each such query includes an estimate of the bandwidth requirement expressed as both minimum and optimal. The infrastructure determines the most even bandwidth distribution based on the needs of all users currently connected. It also factors in the signal quality, adjusting the bandwidth by providing a higher amount to those that could make better use of it, or lowering the amount for poor signal quality. In the latter, for example, a request for video bandwidth from a device with poor signal quality would be allocated the minimum bandwidth required for any given video content type. Such heuristics ensure the most appropriate distribution of bandwidth given any particular set of configurable criteria.
[0043] The process flow of one embodiment is depicted in FIG. 2 . A client device makes a request to the infrastructure component 11 (e.g. the infrastructure mobile/cellular bandwidth provider). The client device queries the provider 12 as to what bandwidth and latency is available. This is the first handshake between client and provider. If this information is available, numerous parameters are returned 13 . These are configurable and may include: available data speed rates; rules relating to the set of applications and request types which can access the bandwidth and in what proportions; the date, time and current location, such as from an embedded GPS device or extrapolated from the cellular data; and so forth. Application and request types are such things as video streaming or other bandwidth intensive or latency sensitive activities. The provider's rules pertaining to bandwidth usage are dynamic and constantly updated. If no such information is available, the client device and/or provider's server perform a download/upload (bandwidth) and latency speed test 14 . This is an important component of one embodiment of the present invention, since the speed test allows collection of information relevant to bandwidth allocation even when the provider does not have such information beforehand. The results of such a test are recorded on the provider's database 15 for future references by other devices in the same coverage area, such that they can proceed directly to stage 13 . From time to time at a configurable interval, the speed test is repeated with other client devices in order to constantly keep the bandwidth and latency information—and therefore the provider's rules—current. The client device receives information from the provider 16 to internally adjust bandwidth requests depending on the application running. For example, in bandwidth intensive applications such as video streaming, the application on the client device adjusts its bit rate according to the information from the provider. Similarly, latency dependent applications may also need to adjust their internal settings accordingly. Rules pertaining to such applications at that particular date and time are subject to constant updates. From time to time at a configurable interval, the client device polls the provider for the latest network information in order to constantly adjust bandwidth usage to optimal levels and account for latency. Applications on the client device make requests for service at specific parameters 17 in compliance with available bandwidth and rules. This is the second handshake between client and provider. The provider evaluates whether requests with desired parameters are valid 18 , as providers and clients may each employ differing interpretations as to which of any specific parameters are prioritized, such as latency. If it is not, then the request is denied or bandwidth is throttled 19 . This is another alternative embodiment of the present invention in that the request for bandwidth may be denied where the desired parameters cannot be fulfilled. In other words, rather than provide a user with a degraded or poorly functioning experience the users' request is denied. If the request and parameters meet the network's information and rules as disclosed in stage 13 , the request is allowed 20 and the process is permitted to continue at the current date and time.
[0044] For example, when a user initiates a video call, the network conditions are checked in the first handshake and if the network is busy the video call can be replaced by a voice call. In another example, the user may request an high definition (HD) version of a video on YouTube, but since the network is busy, the standard definition (SD) version is served instead.
[0045] This could also give network operators the ability to disable video-streaming and audio-streaming services when a network is under heavy usage (so all other types of transfers can go through). For example in case of an emergency (earthquake, tsunami, war), non-essential items (e.g. video streaming from YouTube) can be disabled so that voice call and emergency text messages can be given more priority and more bandwidth.
[0046] The intent of the application is to cover all such combinations and permutations not listed here but that are obvious to the ones skilled in the art. The above examples are not intended to be limiting, but are illustrative and exemplary.
[0047] The examples noted here are for illustrative purposes only and may be extended to other implementation embodiments. While several embodiments are described, there is no intent to limit the disclosure to the embodiment(s) disclosed herein. On the contrary, the intent is to cover all alternatives, modifications, and equivalents obvious to those familiar with the art. | A method is provided for adaptively acquiring bandwidth on a mobile device given traffic prioritization and bandwidth allocation rules of an infrastructure service provider. The device submits to the service provider a first bandwidth query, which includes a first content type and a first bandwidth requirement estimate. The device retrieves from the service provider information as to its traffic prioritization and bandwidth allocation rules and limitations relevant to the first query. This information is made available to the application on the device that needs the bandwidth. The application responds, and the device then sends a second bandwidth query to the service provider which includes a (possibly modified) bandwidth request. Provided this request is valid, bandwidth is obtained for the application on the device according to the request. In a variation, speed test data is used in lieu of or in addition to information from the service provider. | 7 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to an improvement in the techniques of forming flat glass and more precisely of those techniques according to which the glass sheets are shaped by application against a bending mold with forces of a pneumatic nature.
2. Background of the Prior Art
Numerous processes are known of forming a glass sheet according to which the glass sheet is loaded in horizontal position into a reheating furnace intended to bring its temperature to above 500°-600° C., in which it is conveyed on a conveyor such as a roller bed which extends downstream to a bending station. In this latter the sheet is taken over by a mobile transfer device at least in a vertical direction, then placed on a recovery frame which then brings it to the tempering station or to any other cooling station.
Depending on the case, the forming takes place either at the time and after the placing of the glass sheet on the recovery frame which then advantageously consists of an open ring whose contour corresponds to the contour it is desired to impart to the glass sheet, the bending then being performed under the effect of the forces of gravity and inertia, or at the time of taking over of the glass sheet by the transfer element which then comprises an upper bending mold whose curvature corresponds to that of the shaped glass sheet, or also by a combination of the two cases cited above.
The forming processes by application of the glass sheet against the upper bending mold are particularly advantageous, because they allow a better control of the deformation of the glass in its central part, while perfectly meeting the shape desired for the glass contour.
Such a process is described in the publication of French patent FR No. 2 085 464. According to this document, the glass sheet is conveyed into a reheating furnace, in horizontal position, by a conveyor of the roller bed type which extends downstream from the furnace to a bending station. There the glass sheet is immobilized then transferred vertically by a suction due to a low pressure created around the periphery of the sheet, to a curved, nonperforated upper bending mold against which it is applied to be shaped, according to the desired main curvature. The low pressure is obtained by placing the upper bending mold in a box without bottom or skirt, connected to suction means, and whose inside contour is slightly greater than that of the glass sheet while the contour of the upper bending mold is slightly smaller than the latter. Optionally, a complementary curvature is then given to the glass, for example, by pressing.
The main drawback of this type of device comes from the fact that the dimensions and geometry of the upper mold and of the bottomless box are rigorously controlled by those of the glass sheet itself. This means that any modification relating to the glass sheet involves the necessity of simultaneously replacing the box and the upper bending mold.
This replacement must also be performed frequently if the glazings are at least partially enameled. In this case, the enamel at times has a tendency to stick to the covering of the upper bending mold, a covering of refractory paper or fabric glued to the mold with refractory cement. The enamel then causes a rapid deterioration of this covering and the upper mold has to be withdrawn from the bending station, allowed to cool, and a new covering glued in before being able to use it again.
Another limit of this process comes from the fact that to shape glass sheets in a small radius of curvature, considerable suction powers are necessary, the distance between the upper bending mold and the box then being increased because of the curvature of the mold. In practice, this limits the curvatures that can be obtained with this type of forming.
Further, to obtain a sufficient power of suction of the glass sheets, it is necessary that the free space left between the sheet and the side walls of the box remain small. Also, with the slightest offset of the stop position of the glass, the latter hits the side walls of the box at the time of its movement and it must then be rejected.
SUMMARY OF THE INVENTION
This invention processs to improve the technique developed above to reduce its drawbacks, while retaining its advantages.
According to the invention and according to the teaching of the publication of the patent FR No. 2 085 464, the glass sheet is lifted and flattened against an upper bending mold by a low pressure which is exerted on the periphery and in the vicinity of the periphery of the glass sheet. However, and this constitutes an essential difference between this invention and patent FR No. 2 085 464, the lower face of the upper bending mold is placed at least in part on the outside of the low pressure box. In other words, for using the forming process, according to which the glass sheets are brought horizontally into a heating furnace then brought to a bending station where they are transferred individually and vertically to an upper bending mold, the application against the upper mold being obtained by suction due to a low pressure created on the periphery and in the vicinity of the periphery of the glass sheet, according to the invention a device is proposed comprising a low pressure box in which is placed an upper bending mold of dimensions less than that of the glass sheet to be shaped and whose upper face, against which the glass sheet is applied, is located on the outside of the low pressure box, i.e., the lower limit of the side walls of the box is located above the lower limit of the bending mold.
This step taken in regard to the upper mold has the first effect that the glass sheet penetrates the inside of the low pressure box only at the end of flattening, i.e., when it is already shaped in its main curvature and occupies a smaller surface. This naturally causes greater lateral leaks and the need for a greater suction force. However, it appeared that this step appearing minor and rather unfavorable made possible a number of particularly advantageous developments of the invention.
First, there is a direct advantage, as even in the case of a poor centering of the glass sheet in relation to the upper mold, the edges of the sheet will no longer come in contact with the walls of the low pressure box, causing an irreparable marking of the glass.
This freedom of positioning of the sheet relative to the upper mold and especially to the suction box opens up a great number of choices in the relative dimensions of the sheet, the mold and the box.
Thus, when the pieces differ in regard to their dimensions and especially their curvature after forming, the change of the upper mold can be performed without simultaneous replacement of the low pressure box because the upper mold is located according to the invention on the outside (below) of the low pressure box.
This step is more particularly advantageous if, according to a particularly preferred embodiment of the invention, the upper bending mold is made of a light material, for example, of refractory steel which greatly facilitates its handling. Further, with the upper mold advantageously not being mounted solid with the low pressure box, the sole replacement of the upper mold as a function of the dimensions of the glazing is possible on the inside of the heated forming enclosure, with a minimum of caloric losses and in a particularly short time.
Besides reduction of the contacts between the glass and the side walls of the box, it is possible to eliminate practically all contact between the upper bending mold and the piece of glass. This is particularly the case if an upper bending mold is used, equipped with spacing pins on which the glass sheet rests.
According to another preferred embodiment, by way of avoiding absolutely any contact and friction between the glass and the upper bending mold, the upper mold is connected to a hot air intake device, optionally under pressure. Thus a protective air cushion is formed between the upper mold and glass sheet.
Of course, this latter solution is a little more delicate to use than the preceding ones, but it makes possible the treatment, by a single suction mold, of successive glazings not exhibiting, for example, common free surfaces or whose enameled part is located particularly in the central part. Further, the absence of any contact assures a perfect optical quality and this air cushion device can advantageously be used each time such an optical quality is sought.
A preferred embodiment of the invention facilitates the obtaining of forms of glazings that are hard to obtain, requiring a complementary forming after the forming by application against the upper mold. According to this particularly advantageous use, the box is surrounded by a concentric skirt mobile in a vertical direction. This concentric skirt is such that immediately after the take-off of the glass sheet, it determines a temporary box which has dimensions slightly greater than the glass sheet; thus the mobility of the skirt makes it possible easily to introduce a pressing mold in the forming unit and further to reduce the necessary suction power.
BRIEF DESCRIPTION OF THE INVENTION
Other advantages and characteristics of the invention will come out in a more detailed manner in the following description, given with reference to the accompanying drawings which represent:
FIG. 1: A diagrammatic view of a forming unit using a forming device according to an embodiment of the invention,
FIG. 2: A diagrammatic view in longitudinal section of a forming unit, namely a suction box and a mold, made according to the teaching of patent FR No. 2 085 464,
FIG. 3: A longitudinal section of a forming unit according to an embodiment of the invention,
FIG. 4: A longitudinal section of a forming unit with a hot air cushion between the mold and glass sheet,
FIG. 5: A longitudinal section of a forming device comprising a box and a mobile concentric skirt.
DETAILED DESCRIPTION OF THE INVENTION
The forming unit represented in FIG. 1 comprises successively a loading section 1 for glass sheets 2, a glass reheating furnace 3 and a glass forming cell 4.
Furnace 3, whose opening is closed by a series of flexible curtains 5,6 intended to avoid thermal shocks in the furnace at the time of loading the glass, is passed through by a conveyor 7 formed, for example, by a roller bed 8 of vitreous silica sheathed by refractory fabric. This furnace, of the tunnel type, comprises two series 9, 10 of resistors which face each other, placed on both sides of the conveyor and whose temperatures vary as a function of the longitudinal and crosswise position in the furnace to control heating of the glass very precisely. Such a furnace allows a very good control of the heating of the glass to a temperature allowing their forming, generally on the order of 630°-650° C.
Downstream from the furnace, the glass sheet goes into forming unit 4 itself, its arrival being picked up by optical detectors, of the photoelectric type, optionally combined with mechanical detectors, moved by the glass sheet. Such mechanical detectors are, for example, described in French patent application No. 85.13801. Detection of the glass makes it possible to control the simultaneous stopping of the driving of the conveyor rollers located under the forming device. At this time, the glass sheet is lifted under the effect of a powerful suction and is flattened against upper bending mold 11 whose curvature it then assumes. The unit, consisting of the glass sheet and the upper bending mold, and the elements making it possible to create the suction, is then raised to leave sufficient room for the introduction of a glass recovery carriage 12. The formed sheet is finally deposited on said carriage which takes it, thanks to rails placed on both sides of the conveyor, to a subsequent glass treatment cell.
The following description examines in more detail the characteristics of the forming cell itself.
As already mentioned, the main forming device consists essentially of a box without bottom or skirt and a bending mold. A device of the type described in the patent FR No. 2 085 464 has been represented in FIG. 2 to better highlight the differences between the invention which is the object of this application, and the prior art.
In FIG. 2, according to the teaching of said patent FR No. 2 085 464, a bottomless box 22 forms a "skirt" around a mold 23. The box has the same geometric shape as a glass sheet 24 but slightly larger dimensions. Since, on the other hand, bending mold 23 has dimensions slightly less than those of glass sheet 24, a peripheral space remains between the sheet and the bottomless box by which a lateral leak "1" is made which makes it possible to create a low pressure which flattens the glass sheet against mold 23, whose shape it assumes before being recovered by the carriage moved on rails 21. Any change in the dimensions of the glass sheet imposes a modification of the mold and box and, on the other hand, any error in centering the glass sheets leads to a marking of the sheet which has struck the side walls of the low pressure box.
Such drawbacks, on the other hand, are considerably reduced if use is made of an upper bending mold according to the main teaching of the invention and as illustrated by FIG. 3. Actually, advantageously, upper mold here referenced 25 is placed so that glass sheet 26 cannot go into the bottomless box referenced 27, the upper bending mold being placed at a level lower than that of the lower limit of the side walls of the box.
In this way, the deviations in centering of the glass sheets can no longer cause their marking. Further, the upper bending mold is more accessible, especially if in addition it is made of a material that is relatively light but resistant to deformation at the working temperatures necessary here, such as a refractory steel. Besides less weight, a refractory steel further exhibits in relation to the refractory cements recommended by the patent FR No. 2 085 464 the advantage of a great thermal conductivity and therefore a greater rapidity in heating and cooling, a characteristic useful at the times of interruption of the operation of the forming unit for the changes of upper bending molds and in start up. Further, the suction box can then be made in two independent parts, the skirt itself and a suction chamber, parts then provided with dismantling means. Also preferably, the skirt of the suction box is provided with two pins 33, of metal or teflon for example, on which the front edge of the glass sheet strikes which is thus repositioned correctly along the axis of the conveyor.
The need to change the upper bending molds is often due to the degradation of the refractory paper or fabric used to soften the contact between the glass and the bending mold. To reduce the frequency of c.hanges, the device of FIG. 3 can further receive various improvements. First, the upper sheet can be provided with a series of spacing pins against which the glass sheet comes to rest. If the latter is partly enameled, these pins are advantageously placed so that no contact is made between the pins and the enamel, which simultaneously limits the risks of abrasion of the enamel itself and the deterioration of the surface at the upper bending mold, which receives the glass, caused by contact with the enamel of the glass. The invention thus limits the risks of abrasion of the enamel and, on the one hand, eliminates the interruptions due to replacement of the refractory paper or fabric generally used.
In a further preferred embodiment, the spacing pins are eliminated and are replaced by a hot air cushion, this latter solution being preferable from the viewpoint of optical quality. In this way, any contact between the glass and upper bending mold is prevented which is particulary advantageous for forming of glass sheets exhibiting an enameled decor on all of one face or at least in its central part.
This embodiment is shown in FIG. 4. Its principle consists in isolating upper bending mold 25 from suction box 27 put under low pressure with the aid of an aspirator 28 putting under relative pressure a chamber 29 located above upper bending mold 25 and in communication with the lower face of the latter. Thus, in this case the mold being pierced, for example, by a series of microperforations (not shown), an air cushion opposes the contact between glass 26 and upper bending mold 25. Chamber 29 under pressure, depending on the case, can be fed with the aid of a compressor or quite simply be connected to a duct 30 coming out on the outside of box 27 in the forming cell, the low pressure created, moreover, for suction of the glass sheet being sufficient then to create an intake of gas and the pressure necessary for forming the air cushion.
In this case, there is thus no reason for friction between the upper mold and the glass sheet, and the refractory paper or fabric used to improve the state of the contact surface can optionally be eliminated. Further, the two faces of the glass are then placed under the same temperature conditions and a better optical quality probably due to a better thermal homogeneity is thereby found.
The upper bending mold is curved at least longitudinally and its camber is equal to that of the main curvature which it is desired to give to the glass after bending, which therefore corresponds to a forming of the glass essentially by flattening against a mold. However, in particular cases, it is found experimentally that the glass exhibits characteristics requiring overcurving of this upper mold to obtain in the end the desired main curvature.
If use is not made of solid glass recovery carriages but carriages open in their center, a spherical bending of the central part of the glazing then not supported occurs. To remedy this and to obtain a cylindrically shaped glass sheet, it is possible according to an advantageous characteristic of the invention to give to the upper bending mold a crosswise countercurving by giving it, in the direction perpendicular to the main bending direction, a negative chamber which the forces of gravity compensate for at the time of placing the softened glazing on frame 20.
The above-described embodiments of the invention are well suited for obtaining bent glazings with a large radius of curvature. To obtain glazings with a small radius of curvature or complex curvature, particularly multiple radii of curvature, the main bending, assured by application against the upper mold, should be completed by a complementary bending operation, preferably by pressing, although other usual forming means can also be used. For this purpose, it is necessary to introduce under the upper bending mold a pressing mold, or any other equipment for complementary forming of the glass, an operation made delicate by the presence of the skirt.
If the equipment used is too bulky--which is the case, for example, if it is desired to use standard equipment whose dimensions are greater than those of the suction box--it is then preferable to use the embodiment of the invention illustrated, in FIG. 5, according to which skirt 30 is of very small dimensions and is vertically doubled by mobile walls 31. In the low position, these walls reach a level very slightly greater than that of the glass on the conveyor. The low pressure thus produced is right at the periphery of the glass which facilitates the lifting of the sheet. The mobility in height of the walls makes it possible to raise them at the time of introduction of the pressing mold, without having to raise to too great a height the upper bending mold. Walls 31 carry at their lower end pads 32 which rest against the edges of the pressing mold at the time of recovery of the sheet and during the pressing operation if the upper mold is also used as a pressing countermold. Thus, it is seen that the device according to the invention makes it possible to proceed in a very simple way to complementary formings by pressing, essential when the desired shape is complex. Further, thanks to the presence of this additional box formed by mobile walls 31, the suction is always channeled and lateral leaks are minimized.
Obviously, numerous modifications and variations of the present invention are possible in light of the above teachings. It is therefore to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described herein. | A device for forming glass sheets for using the forming process according to which the glass sheets are brought horizontally into a heating furnace then are brought to a forming station where they are transferred individually and vertically to an upper mold exhibiting a radius of curvature less than or equal to the one it is desired to impart to the glass, then are applied against the upper mold by a suction due to a low pressure created on their periphery and in the vicinity of their periphery. The device essentially comprises a suction box in which is placed an upper mold with dimensions slightly less than those of the glass sheet to be shaped and whose lower face, against which the glass sheet is applied, is located on the outside of said suction box. | 2 |
BACKGROUND OF THE INVENTION
The present invention relates to an amplifier for canceling noise generated between circuit systems, and particularly to an analog amplifier, which is applied to, for example, an audio circuit, for preventing noise from being generated to an analog output signal to be sent to the other systems having a different reference potential based on a difference between two circuit systems in the reference potential.
In recent years, an electronic circuit system has become increasingly complicated. In many cases, the circuit is formed on a plurality of circuit boards, and these plurality of circuit systems are connected by a connection line. In the case of connecting the reference potentials, e.g., ground potentials, of different circuit systems, by the connection line, there occurs a case in which a current flows between the reference potentials or a case in which the connection line acts as an antenna to cause noise to be carried on the connection line. As a result, in many cases, a potential difference occurs between the reference potentials of the different circuit systems. The potential difference generally includes an unfavorable noise component. As a result, particularly, the analog circuit is largely damaged.
Moreover, in accordance with the circuit digitalization, there is frequently used a system in which the analog circuit and the digital circuit are mixed. In the digital circuit, since a signal receiving and transmitting is carried out by a pulse having large amplitude of 3 to 5 V, large nose is generated. In this case, since noise, which is generated between the reference potentials, becomes extremely large, the performance of the analog circuit may extremely deteriorated. Therefore, it is very important to prevent the analog section from being unfavorably influenced by such noise.
FIG. 15 shows a mechanism in which noise is generated between reference potentials of two circuit systems each formed on a different circuit boards, that is, ground potentials. Arrows illustrated between two circuit systems 111 and 112 show a direction where a signal is received and transmitted. It is assumed that the total amount of current I1 flows in transmitting a signal from the first circuit system 111 to the second signal system 112 and that the total amount of current I2 flows in transmitting a signal from the second circuit system 112 to the first circuit system 111. As a result, the current of I1-I2 flows into a connection line between reference potentials 113 and 114 of two circuit boards in a direction from the first circuit system 111 to the second circuit system 112. If the connection line serves as an antenna, a current In, which is generated by noise to enter in a form of a radio wave, also flows into the connection line between the reference potentials. If the connection line between the reference potentials has impedance Z, a reference potential difference Vx between two circuit systems can be expressed by the following equation:
Vx=Z×(I2-I1+In)
In this equation, currents I1 and I2 are surely generated in receiving and transmitting the signal. The current I1 and I2 are increased as the system is enlarged and the number of digital circuits is increased. The current In is also increased as the number of the digital circuits is increased, unnecessary amount of radiation is increased and the reference potential connection line becomes long. Moreover, impedance Z is also increased as the connection line between the reference potentials becomes long. Therefore, it can be considered that the reference potential difference Vx becomes large as the scale of the system and the digital section of the system become large.
The DC component of the reference potential difference Vx can be cut by a coupling condenser. However, the AC component is superimposed on the signal component in receiving and transmitting the analog signal. As a result, transmission property is deteriorated.
In order to solve such a problem, a signal receiving and transmitting circuit of a differential output type is conventionally used. FIG. 14 shows one example of such a signal receiving and transmitting circuit. This type of the signal receiving and transmitting circuit comprises an amplifier, a differential amplifier 104, and two signal lines. The amplifier is provided at an output stage of the first circuit system 111 of the signal output side. The amplifier comprises inverting type analog amplifiers 101, 102, and 103 for generating differential signals eo+ and eo- of a signal eil to be transmitted. The differential amplifier 104 is provided at an input stage of the second circuit system 112 of the signal input side. The differential signals eo+ and eo- are input to the differential amplifier 104. Two signal lines transmit the differential signals. This type of the circuit transmits the signal in the form of a differential signal, and receives the signal in the form of a differential signal. As a result, the noise component, which is generated since the reference potentials are not common, is canceled. More specifically, in FIG. 14, it is assumed that the following equations are set:
R102/R101=1, R104/R103=R106/R105=A
As a result, the potentials eo+ and eo- of the first circuit system, which are seen from the reference potential 113 of the first circuit system, can be obtained as follows:
eo+=A×ei1, eo-=-A×ei1
The potentials eo+ and eo-, which are seen from the differential amplifier 104 of the second circuit system 112, are based on the reference potential 114 of the second circuit system, and these potentials can be obtained as follows:
eo+=A×ei1+Vx, eo-=-A×ei1+Vx
If the gain of the differential amplifier 104 of the second circuit system is A', an output potential eo2 of the differential amplifier 104 can be obtained as follows. ##EQU1##
Thus, noise Vx can be prevented from appearing in the output potential eo2.
However, in the conventional circuit, three output amplifiers and two signal lines are needed in the transmitter side and the differential input amplifier is needed in the receiver side. As a result, the manufacturing cost and the circuit occupying area are increased.
BRIEF SUMMARY OF THE INVENTION
An object of the present invention is to provide a circuit for receiving and transmitting a signal without an increasing manufacturing cost and a circuit occupying area and generating a noise component.
The object can be achieved by the following structure.
There is provided an amplifier comprising:
a first circuit system having an analog amplifier for amplifying a transmitting signal based on a reference potential of the first circuit system;
a second circuit system for receiving an output signal of the analog amplifier based on a reference potential of the second circuit system; and
a reference potential difference canceling circuit wherein the reference potential of the second circuit system is supplied to an input terminal, an output signal is supplied to the input terminal of the analog amplifier together with the transmitting signal, and a gain, from the input terminal to an output terminal of the analog amplifier, is 1.
Additional objects and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out in the appended claims.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING
The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate presently preferred embodiments of the invention, and together with the general description given above and the detailed description of the preferred embodiments given below, serve to explain the principles of the invention.
FIG. 1 is a view showing an embodiment of the present invention;
FIG. 2 is a view showing an embodiment of the present invention using an inverting type amplifier;
FIG. 3 is a view showing an embodiment of the present invention using an inverting type amplifier of a single power supply;
FIG. 4 is a view showing an embodiment of the present invention using a non-inverting type amplifier;
FIG. 5 is a view showing another embodiment of the present invention using a non-inverting type amplifier;
FIG. 6 is a view showing an embodiment of the present invention using a differential amplifier;
FIG. 7 is a view showing an embodiment of the present invention using a differential amplifier of a single power supply;
FIG. 8 is a view showing an embodiment of the present invention using an inverting type amplifier and an input line for a reference potential difference canceling circuit in common;
FIG. 9 is a view showing an embodiment of the present invention using a non-inverting type amplifier and an input line for a reference potential difference canceling circuit in common;
FIG. 10 is a view showing an embodiment of the present invention using an inverting type amplifier and a reference potential difference canceling circuit in common;
FIG. 11 is a view showing an embodiment of the present invention using a non-inverting type amplifier and a reference potential difference canceling circuit in common;
FIG. 12 is a view showing an embodiment of the present invention using a switched capacitor in an inverting type amplifier;
FIG. 13 is a view showing the relationship between the switched capacitor and resistance;
FIG. 14 is a view showing a prior art; and
FIG. 15 is a view showing a mechanism for generating the reference potential difference between two circuit systems.
DETAILED DESCRIPTION OF THE INVENTION
The following will explain the embodiments of the present invention with reference to the drawings.
FIG. 1 shows an embodiment of the present invention. In the following explanation, the same reference numerals are added to the structural elements in common to each other, and the specific explanation will be omitted.
In the embodiment shown in FIG. 1, each of first and second circuit systems 11 and 12 is formed on a different circuit board. The reference potential of the first circuit system 11 is different from that of the second circuit system 12. An analog signal is transmitted from the first circuit system 11 to the second circuit system 12.
A reference potential 13 of the first circuit system 11 and a reference potential 14 of the second circuit system 12 are normally set to a ground potential. In FIG. 1, these reference potentials are shown by a different ground potential mark. These two systems are electrically connected to each other through impedance Z formed between the reference potentials 13 and 14. Noise Vx is generated between both ends of impedance Z by the above-mentioned reason.
In the first circuit system 11, a signal ei1 is supplied to an input terminal of an analog amplifier 1 whose gain is A. An output signal of the analog amplifier 1 is transmitted to the second circuit system 12 to be supplied to an input terminal of an analog amplifier 2. If there is no reference potential difference canceling circuit 3, an input signal of the analog amplifier 2 of the second circuit system becomes A×ei1+Vx by providing that the reference potential of the second circuit system is set as a reference. As a result, the difference Vx between the reference potentials 13 and 14 of two circuit systems is directly input to the second circuit system 12. Then, the reference potential difference canceling circuit 3 whose gain is 1/A is provided in the first circuit system 11. An input terminal of the circuit 3 is connected to a ground point 14, which is the reference potential of the second circuit system 12. Then, an output signal of the circuit 3 is supplied to the input terminal of the analog amplifier 1 with the signal ei1.
In this case, the reference potential 13 of the first circuit system is set as a reference, so an output signal eo1 of the analog amplifier 1 becomes as follows: ##EQU2##
The reference potential 14 of the second circuit system is set as a reference, so an input signal ei2 of the analog amplifier 2 becomes as follows: ##EQU3##
In this way, noise component Vx can be removed.
According to the above-mentioned embodiment, one analog amplifier and the simple reference potential difference canceling circuit are used, so that the signal can be received and transmitted between the different circuit systems without generating the noise component. As a result, it is unnecessary to provide an amplifier for generating a differential signal and an amplifier for receiving the differential signal. Thereby, the manufacturing cost and the circuit occupying area can be reduced.
FIG. 2 shows an embodiment of the present invention using an inverting type amplifier as the analog amplifier 1 shown in FIG. 1.
In the first circuit system 11, the signal ei1 is supplied to one end of a resistor R1, and the other end of the resistor R1 is connected to an inverting input terminal of an operational amplifier 21. The inverting input terminal of the operational amplifier 21 is connected to one end of a resistor R2, and the other end of the resistor R2 is connected to an output terminal of the operational amplifier 21. The output terminal of the operational amplifier 21 is connected to an input terminal of the analog amplifier 2 of the second circuit system. The reference potential 14 of the second circuit system 12 is supplied to the input terminal IN of the canceling circuit 3 of the first circuit system 11. The canceling circuit 3 is a potential divider using the resistor. In the canceling circuit 3, a resistor R3 is provided between the input terminal IN and the output terminal OUT. A resistor R4 is provided between the output terminal OUT and the reference potential 13 of the first circuit system. The output terminal OUT of the canceling circuit 3 is connected to a non-inverting input terminal of the operational amplifier 21.
In this embodiment, gain A- of the analog amplifier 1, which is seen from the inverting input signal of the operational amplifier 1, that is, one end of the resistor R1, is as follows:
A-=-R2/R1
Moreover, gain A+ of the analog amplifier 1, which is seen from the non-inverting input signal of the analog amplifier 1, that is, the non-inverting input terminal of the operational amplifier 21, is as follows:
A+=(R1+R2)/R1
Therefore, in the canceling circuit 3, it is assumed that the following equation is given: ##EQU4##
As a result, the gain, which is from the input terminal IN of the canceling circuit 3 to the output terminal of the analog amplifier 1, becomes 1. In this case, the reference potential 13 of the first circuit system is set as a reference, so the output potential eo1 of the analog amplifier 1 becomes as follows:
eo1=(-R2/R1)×ei1-Vx
Therefore, the reference potential 14 of the second circuit system is set as a reference, so the input potential ei2 of the analog amplifier 2 becomes as follows: ##EQU5##
In this way, noise Vx can be canceled.
According to the above-mentioned embodiment, one analog amplifier and the simple reference potential difference canceling circuit are used, so that the signal can be received and transmitted between the different circuit systems without generating the noise component. As a result, it is unnecessary to provide an amplifier for generating a differential signal and an amplifier for receiving the differential signal. Thereby, the manufacturing cost and the circuit occupying area can be reduced.
FIG. 3 shows an embodiment of the present invention using an inverting input type amplifier as the analog amplifier 1 of a single power supply.
The analog amplifier 1 of this embodiment comprises an operational amplifier 21, and resistors R1 and R2, and is the same as the analog amplifier of FIG. 2. The signal ei1 is supplied to one end of the resistor R1, and the other end of the resistor R1 is connected to an inverting input terminal of the operational amplifier 21. An output terminal of the operational amplifier 21 is connected to the input terminal of the analog amplifier 2 of the second circuit system through a coupling condenser C1.
The reference potential 14 of the second circuit system 12 is supplied to the input terminal IN of the canceling circuit 3 of the first circuit system 11 through a coupling condenser C2.
In the canceling circuit 3, a resistor R15 is provided between the input terminal IN and the output terminal OUT. A resistor R13 is provided between a power supply potential VDD of the first circuit system and the output terminal OUT. A resistor R14 is provided between the output terminal OUT and the reference potential of the first circuit system. The output terminal OUT of the canceling circuit 3 is connected to the non-inverting input terminal of the operational amplifier 21.
In the embodiment shown in FIG. 2, since the input signal ei1 of the analog amplifier 1 swings around a ground potential, positive and negative power-supply sources are needed as a power supply for the analog amplifier 1. In the case of using the single power supply, the input signal ei1 cannot swing around the ground potential. Due to this, another reference potential Vref must be provided. The reference potential Vref is normally set to a half of the power supply potential. In this case, the input signal ei1 of the analog amplifier 1 becomes as follows:
ei1=es+Vref
In this case, es is an input signal, which does not include a DC component. As a result, the input signal ei1 swings around the reference potential Vref. The canceling circuit 3 shown in FIG. 3 is also used as a Vref generator. The reference potential Vref is a DC value. The Reference potential Vref is provided on a common junction of the resistors R13 and R14 by dividing the potential between the power supply potential VDD and the reference potential 13. In a case where the power supply potential VDD is unstable, there can be considered a method in which a stable potential is created and the reference potential Vref is provided by dividing the potential between the stable potential and the reference potential 13.
Unlike the embodiment shown in FIG. 2, the input terminal IN of the canceling circuit 3 shown in FIG. 3 is connected to the reference potential 14 of the second circuit system through the coupling condenser C2. Due to this, only AC component of noise Vx is input to the canceling circuit 3. In other words, DC component of noise Vx cannot be canceled. However, in the case of the single power supply, the output terminal of the analog amplifier 1 and the input terminal of the analog amplifier 2 are connected to each other through the coupling condenser C1. In this case, since the DC component does not pass through the coupling condenser C1, it is unnecessary to cancel the DC component. The gain of the canceling circuit 3 against the AC component can be obtained by replacing the resistor R4 in FIG. 2 with the parallel connection of resistors R13 and R14. If the resistance value of the parallel connection is set to R4', the following equation can be established:
R4'=R13×R14/(R13+R14)
To cancel noise, the following equation may be established: ##EQU6##
Therefore, if the following equation is established, the AC component of noise Vx can be canceled similar to the case of FIG. 2.
R4'/R15=R1/R2 (R13×R14)/ (R13+R14)×R15!=R1/R2
According to the above-mentioned embodiment, one analog amplifier and the simple reference potential difference canceling circuit are used, so that the signal can be received and transmitted between the different circuit systems without generating the noise component. As a result, it is unnecessary to provide an amplifier for generating a differential signal and an amplifier for receiving the differential signal. Thereby, the manufacturing cost and the circuit occupying area can be reduced.
Moreover, according to the above-mentioned embodiment, since the reference potential difference canceling circuit is also used as the Vref generator in operating the amplifier by the single power supply. As a result, increase in the number of parts can be prevented.
FIG. 4 shows an embodiment of the present invention using a non-inverting type amplifier as an analog amplifier.
The signal ei1 is supplied to a non-inverting input terminal of an operational amplifier 41. An output terminal of the operational amplifier 41 is connected to the input terminal of the analog amplifier 2 of the second circuit system 12. One end of a resistor R41 is connected to the non-inverting input terminal of the operational amplifier 41 and one end of a resistor R42. The other end of the resistor R42 is connected to the output terminal of the operational amplifier 41.
The reference potential 14 of the second circuit system 12 is supplied to the input terminal IN of the canceling circuit 3. In the canceling circuit 3, the input terminal IN of the canceling circuit 3 is connected to one end of a resistor R43, and the other end of the resistor R43 is connected to the inverting input terminal of the operational amplifier 42. Also, the output terminal of the operational amplifier 42 is connected to one end of a resistor R44, and the other end of the resistor R44 is connected to the inverting input terminal of the operational amplifier 42. A non-inverting input terminal of the operational amplifier 42 is connected to the reference potential 13 of the first circuit system 11. The output terminal of the operational amplifier 42, that is, the output terminal OUT of the canceling circuit 3 is connected to the other end of the resistor R41. The operational amplifier 42 serves as a buffer amplifier for supplying an output of Vx times (-R44/R43) at a low impedance to the output terminal OUT of the reference potential difference canceling circuit 3.
Then, gain A- of the analog amplifier 1 seen from the inverting input signal of the analog amplifier 1, that is, the other end of the resistor R41 can be given as follows:
A-=-R42/R41
Therefore, if the following equation is given,
R44/R43=R41/R42
the gain, which is from input terminal IN of the canceling circuit 3 to the output terminal of the amplifier 1, becomes 1. As a result, the following equation can be established. ##EQU7##
Then, it is possible to prevent noise Vx from appearing in the input signal ei2 of the analog amplifier 2.
According to the above-explained embodiment, by use of one analog amplifier and the simple reference potential difference canceling circuit, the signal can be received and transmitted between the different circuit systems without generating the noise component. As a result, the amplifier for generating a differential signal and the amplifier for receiving the differential signal are not needed, so that the manufacturing cost and the circuit occupying area can be reduced.
FIG. 5 is an embodiment of the present invention showing a case in which the circuit of FIG. 4 is operated by a single power supply.
In the embodiment of FIG. 5, a non-inverting type amplifier is used as the analog amplifier 1. The signal ei1 is supplied to a non-inverting input terminal of an operational amplifier 51. A inverting input terminal of the operational amplifier 51 is connected to one end of the resistor R41, and the other end of the resistor R41 is connected to the output terminal OUT of the canceling circuit 3. Also, the inverting input terminal of the operational amplifier 51 is connected to one end of the resistor R42, and the other end of the resistor R42 is connected to the output terminal of the operational amplifier 51. The output terminal of the operational amplifier 51 is connected to the input terminal of the analog amplifier 2 of the second circuit system through the coupling condenser C1. The input terminal IN of the canceling circuit 3 is connected to the reference potential 14 of the second circuit system through the coupling condenser C2.
In the canceling circuit 3, the input terminal IN of the canceling circuit 3 is connected to one end of the resistor R43, and the other end of the resistor R43 is connected to the inverting input terminal of an operational amplifier 52. The inverting input terminal of the operational amplifier 52 is connected to one end of the resistor R44, and the other end of the resistor R44 is connected to the output terminal of the operational amplifier 52. A non-inverting input terminal of the operational amplifier 52 is connected to another reference potential Vref having a constant potential difference to the reference potential 13 of the first circuit system. As mentioned in the explanation of FIG. 3, the reference potential Vref is supplied from a voltage divider using the power supply potential VDD and the reference potential 13 or using the constant power supply.
In this embodiment, AC component of Vx can be canceled by satisfying the equation shown in the embodiment of FIG. 4. Specifically, if R44/R43=R41/R42 is established, the gain, which is from the input terminal IN of the canceling circuit 3 to the output terminal of the analog amplifier 1, becomes 1. As a result, noise of the input signal of the analog amplifier 2 can be canceled. In this embodiment, similar to the embodiment of FIG. 3, the canceling circuit 3 is also used as Vref generator.
Thus, according to the above-explained embodiment, by use of one analog amplifier and the simple reference potential difference canceling circuit, the signal can be received and transmitted between the different circuit systems without generating the noise component. As a result, the amplifier for generating a differential signal and the amplifier for receiving the differential signal are not needed, so that the manufacturing cost and the circuit occupying area can be reduced.
Moreover, according to the above-mentioned embodiment, since the reference potential difference canceling circuit is also used as the Vref generator in operating the amplifier by the single power supply. As a result, increase in the number of parts can be prevented.
FIG. 6 is an embodiment showing a case of using a differential amplifier as the analog amplifier 1.
In this embodiment, the signal ei- is supplied to one end of a resistor R61, and the other end of the resistor R61 is connected to an inverting input terminal of an operational amplifier 61. The inverting input terminal of the operational amplifier 61 is connected to one end of a resistor R62, and the other end of the resistor R62 is connected to the output of the operational amplifier 61. The signal ei+ is supplied to one end of a resistor R63, and the other end of the resistor R63 is connected to the non-inverting input terminal of the operational amplifier 61. The output terminal of the operational amplifier 61 is connected to the input terminal of the analog amplifier 2 of the second circuit system 12.
The reference potential 14 of the second circuit system is supplied to the input terminal IN of the canceling circuit 3 of the first circuit system 11. The canceling circuit 3 comprises a resistor R64, and R65. One end of the resistor R64 is connected to the input terminal IN of the canceling circuit 3, and the other end of the resistor R64 is connected to the output terminal OUT of the canceling circuit 3. One end of a resistor R65 is connected to the other end of the resistor R64, and the reference potential 13 of the first circuit system is supplied to the other end of the resistor R65. The output terminal OUT of the canceling circuit 3 is connected to the non-inverting input terminal of the operational amplifier 61.
In this embodiment, the output signal eo1 of the analog amplifier 1 can be expressed as follows:
eo1= (R61+R62)/R61!× R64'/(R63+R64')!×(ei+)-R62/R61×(ei-)
where, R64'=R64×R65/(R64+R65)
Similar to the case shown in FIG. 2, the gain A+ of the analog amplifier 1 seen from the non-inverting input terminal can be expressed as follows:
A+=(R61+R62)/R61.
Moreover, the gain A', which is from the input terminal IN of the canceling circuit 3 to the output terminal OUT, can be expressed as follows:
A'=R63'/(R63'+R64)
where, R63'=R63×R65/(R63+R65)
If the equation, A'=1/(A+), is established, Vx can be canceled.
Therefore, R63'/(R63'+R64)=R61/(R61+R62) may be established.
Then, if the following equation is given, Vx can be canceled.
R63'/R64=R61/R62 R63×R65/ (R63+R65)×R64!=R61/R62.
Thus, according to the above-explained embodiment, by use of one analog amplifier and the simple reference potential difference canceling circuit, the signal can be received and transmitted between the different circuit systems without generating the noise component. As a result, the amplifier for generating a differential signal and the amplifier for receiving the differential signal are not needed, so that the manufacturing cost and the circuit occupying area can be reduced.
FIG. 7 is an embodiment of the present invention showing a case in which the circuit of FIG. 6 is operated by a single power supply.
In the embodiment of FIG. 7, the differential analog amplifier 1 is the same as the differential analog amplifier of FIG. 6. An output terminal of an operational amplifier 71 is connected to the input terminal of the analog amplifier 2 of the second circuit 12 of the second circuit system 12 through the coupling condenser C1. The reference potential 14 of the second circuit system is supplied to the input terminal IN of the canceling circuit 3 through the coupling condenser C2.
The canceling circuit 3 comprises resistors R64, R65, and R66. Power potential VDD of the first circuit system is supplied to one end of the resistor R66, and the other end of the resistor R66 is connected to the output terminal OUT of the canceling circuit 3. One end of the resistor R65 is connected to the other end of the resistor R66, and the reference potential 13 of the first circuit system 1 is supplied to the other end of the resistor R65. One end of the resistor R64 is connected to the input terminal IN of the canceling circuit 3, and the other end of the resistor R64 is connected to the connection point between the resistors R65 and R66. The output terminal OUT of the canceling circuit 3 is connected to a non-inverting input terminal of an operational amplifier 71.
In this embodiment, the resistor R65 of FIG. 6 is replaced with R65×R66/(R65+R66), so that the resistance condition for canceling Vx can be obtained. Similar to the embodiments of FIGS. 3 and 5, the canceling circuit 3 of this embodiment is also used as a Vref generator.
Thus, according to the above-explained embodiment, by use of one analog amplifier and the simple reference potential difference canceling circuit, the signal can be received and transmitted between the different circuit systems without generating the noise component. As a result, the amplifier for generating a differential signal and the amplifier for receiving the differential signal are not needed, so that the manufacturing cost and the circuit occupying area can be reduced.
Moreover, according to the above-mentioned embodiment, since the reference potential difference canceling circuit is also used as the Vref generator in operating the amplifier by the single power supply. As a result, increase in the number of parts can be prevented.
FIG. 8 is an embodiment showing a case in which a line for connecting the input terminal IN of the canceling circuit 3 to the second reference potential of the second circuit system is shared when the circuit shown in FIG. 3 is provided for two channels.
In this embodiment, analog amplifiers 1a and 1b and canceling circuits 3a and 3b, which are similar to those shown in FIG. 3, are provided in the first circuit system 11. The output signals of the analog amplifiers 1a and 1b are supplied to the input analog amplifiers 2a and 2b of the second circuit system 12 through coupling condensers C1a and C1b, respectively. The input terminals IN of the canceling circuits 3a and 3b are connected to the reference potential 14 of the second circuit system 12 through a common coupling condenser C2.
Thus, according to this embodiment, the signal can be received and transmitted between the different circuit systems without generating the noise component. Moreover, the number of condenser C2 for cutting the DC component can be one, so that the number of signals lines and the number of parts of the circuit can be reduced.
Similarly, in a case where three or more channels are provided in the circuit, the input signal line for the canceling circuit can be shared.
The embodiment of FIG. 8 shows the case of the single power supply. However, even in the case of two power supplies as shown in FIG. 2, the connection line between the canceling circuit and the reference potential of the second circuit system can be shared.
Similar to FIG. 8, FIG. 9 is an embodiment showing a case in which an input signal line of the canceling circuit 3 is shared when the circuit shown in FIG. 5 is provided for two channels.
In this embodiment, in the first circuit system, two analog amplifiers 1a and 1b, which are the same as described in FIG. 5, and two reference potential difference canceling circuits 3a and 3b, which are the same as described in FIG. 5, are provided. The output signals of analog amplifiers 1a and 1b are supplied to input amplifiers 2a and 2b of the second circuit system through coupling condenser C1a and C1b, respectively. The input terminal IN of each of the canceling circuits 3a and 3b is connected to the reference potential 14 of the second circuit system through the common condenser C2.
According to this embodiment, the signal can be received and transmitted between the different circuit systems without generating the noise component. Similar to the embodiment of FIG. 8, the increase in the number of signal lines and the number of parts can be prevented.
Moreover, in the case of three or more channels, the input signal line of the canceling circuit 3 can be used as a common input signal line.
The embodiment of FIG. 9 showed the case of the single power source. However, even in the case of two power supplies as shown in FIG. 4, the connection line between the input terminal of the canceling circuit 3 and the reference potential of the second circuit system can be used as a common connection line.
FIG. 10 shows an embodiment in which the reference potential difference canceling circuit 3 is used as a common circuit when the circuit shown in FIG. 3 is provided for two channels.
In the first circuit system 11, one canceling circuit 3, which is the same as shown in FIG. 3, and two inverting type analog amplifiers 1a and 1b, which are the same as shown in FIG. 3, are provided. The output signals of the analog amplifiers 1a and 1b are supplied to the input amplifiers 2a and 2b of the second circuit system through the coupling condensers C1a and C1b, respectively. The input terminal IN of the canceling circuit 3 is connected to the reference potential 14 of the second circuit system through the coupling condenser C2. The output terminal OUT of the canceling circuit 3 is connected to the non-inverting input terminal of the operational amplifier 21a of the analog amplifier 1a and the non-inverting input terminal of the operational amplifier 21b of the analog amplifier 1b.
According to this embodiment, the signal can be received and transmitted between the different circuit systems without generating the noise component. The number of parts can be more reduced than the embodiment of FIG. 8.
Moreover, in the case of three or more channels, the canceling circuit 3 can be used as a common circuit.
The embodiment of FIG. 10 showed the case of the single power supply. However, even in the case of two power supplies as shown in FIG. 2, the canceling circuit 3 can be used as a common circuit.
FIG. 11 shows an embodiment in which the reference potential difference canceling circuit 3 is used as a common circuit when the circuit shown in FIG. 5 is provided for two channels.
In the first circuit system 11, one canceling circuit 3, which is the same as shown in FIG. 5, and two inverting type analog amplifiers 1a and 1b, which are the same as shown in FIG. 5, are provided. The output signals of the analog amplifiers 1a and 1b are supplied to the input amplifiers 2a and 2b of the second circuit system 12 through the coupling condensers C1a and C1b, respectively. The input terminal IN of the canceling circuit 3 is connected to the second reference potential of the second circuit system through the coupling condenser C2. The output terminal OUT of the canceling circuit 3 is connected to each of the inverting input terminals of operational amplifiers 51a and 51b through each of resistors R41a and R41b.
According to this embodiment, the signal can be received and transmitted between the different circuit systems without generating the noise component. The number of parts can be more reduced than the embodiment of FIG. 9.
Even in a case of three or more channels, the canceling circuit 3 can be used as a common circuit.
The embodiment of FIG. 11 showed the case of the single power supply. However, even in the case of two power supplies as shown in FIG. 4, the canceling circuit 3 can be used as a common circuit.
FIG. 12 shows an analog amplifier using a switched capacitor.
In the circuit shown in FIG. 12, the resistors R1 and R2, which are connected to the operational amplifier 21 of the analog amplifier 1 shown in FIG. 2, are replaced with the switched capacitor.
As shown in FIG. 13, the switched capacitor comprises a capacitor C, a switch SWa and a switch SWb. The switch SWa has a movable contact, which is connected to the first terminal of the capacitor C, and a fixed contact, which is connected to a terminal a and the reference potential. The switch SWb has a movable contact, which is connected to the second terminal of the capacitor C, and a fixed contact, which is connected to a terminal b and the reference potential. The switched capacitor can be considered to be equivalent to the resistor R of FIG. 13 by the following equation.
T/C=R
In this case, T shows a period of the opening and closing of each of SWa and SWb. This equation can be established when the frequency of the signal is sufficiently low against f=1/T. SW1, SW2, and C11 of FIG. 12 correspond to R1 of FIG. 2, and SW2, SW3, and C2 correspond to R2 of FIG. 2.
Even in the circuit using the switched capacitor, the same advantage as in the above embodiments using the resistor can be obtained. Moreover, since the resistor value R can be changed by changing the period T, variations in the manufacture can be controlled.
Additional advantages and modifications will readily occur to those skilled in the art. Therefore, the invention in its broader aspects is not limited to the specific details and representative embodiments shown and described herein. Accordingly, various modifications may be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and their equivalents. | A reference potential difference canceling circuit is provided in a circuit system of a transmitter side to remove noise caused by impedance Z between circuit systems having different reference potentials from a signal, and to transmit the signal. The reference potential of the circuit system of a receiver side is supplied to an input terminal of the reference potential difference canceling circuit, and its output terminal is connected to an input terminal of an output amplifier to which a transmitting signal is input. A gain of the reference potential difference canceling circuit is set to a reciprocal number of a gain of the output amplifier. | 7 |
TECHNICAL FIELD
[0001] The present disclosure relates generally to hand tools, and, more particularly, to a multi-function tool suitable for various demolition tasks.
BACKGROUND OF THE INVENTION
[0002] Many construction or building projects, including demolition tasks, require a plurality of functions for proper completion. Accordingly, numerous specialized tools are frequently needed to perform specific respective functions. For large or complex jobs, the acquisition, storage, and/or maintenance of a large number of specialized tools required may become burdensome and/or expensive.
[0003] In order to alleviate such burden and to reduce such cost, multi-function tools have been designed to allow a single tool to perform two or more tasks. The specific functionality selected for a multi-function tool is typically selected to allow performance of tasks or functions that are commonly necessary to complete a single project. For example, the common roofing project of shingling frequently requires both a striking function to drive nails, as well as a cutting function to adjust shingle size. Accordingly, hammers having a striking surface and cutting means have been developed and employed to make performance of both functions more convenient. Unfortunately, the number of such multi-function tools is limited, typically to jobs or projects that require relatively few functions, such as two or three. For many projects, however, many more functions are necessary, even if infrequently, and thus require numerous specialized tools, including one or more of multi-function tool(s).
[0004] Thus, it is clear that there is an unmet need for a multi-function tool that conveniently enables performance of a greater number of functions, whereby the number of specialized tools required to complete a large or complex job may be reduced, preferably to a single tool, and whereby the need for storage and carriage of a large number of tools may be reduced or eliminated.
BRIEF SUMMARY OF THE INVENTION
[0005] Briefly described, in an exemplary embodiment, the multi-function tool of the present disclosure overcomes the above-mentioned disadvantages and meets the recognized need for such a tool by providing a multi-function tool providing a hammer function, a first-class lever function, a second-class lever function, a chisel function, an axe function, a wrench function, and a scoring function, among others.
[0006] More specifically, the exemplary multi-function tool includes a generally extended handle portion, such as in the form of a bar or shaft, and a plurality of structures associated therewith, each structure configured and arranged to enable performance of at least one function or task. The handle portion preferably includes a grip for comfortable secure grasping and manipulation. The handle portion further preferably terminates at a first end in a chisel point or blade, whereby the handle portion may be used to drive the chisel point or blade, such as for chiseling, chipping, gouging, or puncturing, or to manipulate the point or blade, such as for scoring or cutting. A wrench structure may additionally be included proximate the first end, whereby nuts, bolts, or other threaded fasteners, or the like, may be adjusted. Furthermore, a nail or other fastener removing structure may be included proximate the first end, such as a second-class lever nail puller.
[0007] A hammer head is preferably included on a second end of the handle portion having a striking face radially spaced from a longitudinal axis of the handle portion in a first direction. The striking face may be smooth or textured, such as having a waffle pattern. A claw is preferably also included on the second end of the handle portion extending generally radially from the longitudinal axis of the handle portion in a second direction. The claw portion may be configured for use in prying a first-class lever, including for pulling nails, or the like, and may additionally include chisel blades, or the like, for chipping or chiseling. An axe blade is preferably further included proximate the second end of the handle, such as formed over a lateral edge of the side handle, preferably at a transition between the handle portion or grip proximate the hammer head and/or the claw. The axe blade may enable a cutting and/or chopping function.
[0008] The second end of the handle portion may optionally further be provided with a slot adapted to receive a member, such as a piece of dimensional lumber, or the like, whereby the handle portion may be used to wrench or lever the member. The slot may include a varying dimension or a plurality of slots having different dimensions may be provided in order to accommodate members having different dimensions. Additionally, teeth or other textured gripping structures or surfaces may be included to ensure secure gripping of the member in the slot.
[0009] Generally, the exemplary multi-function tool is configured such that any enabled function may be performed without interference from structures of the tool that enable different functionality without reconfiguration or other manipulation. Accordingly, the tool need not be adjusted in order to accomplish any function, whereby transition between performance of various functions may be accomplished quickly and conveniently. Furthermore, the configuration of the tool is preferably selected to at least partially imitate the general configuration of known tools, such as the overall configuration of a hammer, whereby the tool may be used with conventional accessories, such as a toolbox or case, a tool belt, or the like.
[0010] Accordingly, one feature and advantage of the tool of the present disclosure is its ability to provide a tool useful for the performance of a plurality of different tasks whereby acquisition, storage, and/or maintenance of a plurality of task-specific tools may be avoided.
[0011] Another feature and advantage of the present tool is its ability to enable quick and convenient transition between the performance of different one of a plurality of various functions.
[0012] These and other features and advantages of the tool of the present disclosure will become more apparent to those ordinarily skilled in the art after reading the following Detailed Description of the Invention and Claims in light of the accompanying drawing Figures.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] Accordingly, the present disclosure will be understood best through consideration of, and with reference to, the following drawings, viewed in conjunction with the Detailed Description of the Invention referring thereto, in which like reference numbers throughout the various drawings designate like structure, and in which:
[0014] FIG. 1 is a perspective view of a multi-function tool;
[0015] FIG. 2 is a side view of the tool of FIG. 1 ; and
[0016] FIG. 3 is a side view of a multi-function tool according to an alternative configuration.
[0017] It is to be noted that the drawings presented are intended solely for the purpose of illustration and that they are, therefore, neither desired nor intended to limit the scope of the disclosure to any or all of the exact details of construction shown, except insofar as they may be deemed essential to the claimed invention.
DETAILED DESCRIPTION OF THE INVENTION
[0018] In describing exemplary embodiments of the tool of the present disclosure illustrated in the drawings, specific terminology is employed for the sake of clarity. The invention, however, is not intended to be limited to the specific terminology so selected, and it is to be understood that each specific element includes all technical equivalents that operate in a similar manner to accomplish a similar purpose.
[0019] In that form of the tool of the present disclosure chosen for purposes of illustration, FIGS. 1 and 2 show tool 100 including body 101 and grip 103 . Body 101 is preferably formed as a monolithic or unitary member from a suitable metal, composite, or synthetic material, or the like and includes grip 103 formed or installed thereon. Grip 103 may be formed from natural or synthetic rubber, plastic, composite, or the like, and may be resilient and/or sculptured or contoured to provide a comfortable and secure grasping surface. Grip 103 is preferably disposed proximate a medial portion of body 101 along longitudinal axis 102 . Body 101 preferably includes first end 101 a and second end 101 b each extending beyond grip 103 , and each preferably carrying or including at least one structure adapted to enable at least one associated function.
[0020] For example, and as illustrated best in FIG. 2 , first end 101 a preferably includes chisel 111 and/or blade 113 . Additionally, first end 101 a may include first and second wrench apertures 115 and 117 , respectively, adapted to engage nuts, bolts, or the like, of different sizes. Slot 119 may further be included for prying nails or the like. As will be understood by those ordinarily skilled in the art, the sizes, shapes, or other configuration parameters selected for each of chisel 111 , blade 113 , wrench apertures 115 and 117 , and/or slot 119 may be selected as desired, such as for use with commonly found fasteners, materials, or tasks. For example, chisel 111 may be formed as a pointed member, as illustrated in FIG. 2 or as a flat member, as illustrated in FIG. 3 , depending on a material with which tool 100 is intended to be used. Similarly, the sizes and configurations of wrench apertures 115 and 117 , e.g. half inch hex pattern, may be selected as desired. As will further be understood by those ordinarily skilled in the art, first end 101 a may include additional and/or alternative structures to enable additional and/or alternative functions, such as a Phillips or flat head screwdriver bit, a saw blade, a rasp surface, wire stripping slots, an awl, or the like.
[0021] Second end 101 b preferably includes a generally V-shape having first projection 105 and second projection 107 . First projection 105 preferably includes hammer head 121 disposed or formed generally at a distal end thereof and spaced radially from longitudinal axis 102 . Hammer head 121 may include a smooth or textured face and is preferably configured and arranged for at least one of driving fasteners, breaking objects, or moving objects. Accordingly, first projection 105 is preferably configured to withstand repeated substantial impact forces without failure. Hammer head 121 and/or first projection 105 may additionally include one or more structures, such as a magnetic nail holder, bottle opener 123 , or the like. Second projection 107 is preferably arranged opposite first projection 105 and includes claw 125 extending away from longitudinal axis 102 . Claw 125 may include slot 127 for pulling nails, or the like, and/or at least one blade 129 for use in chipping, chiseling, or prying. Second projection 107 preferably further includes blade 131 formed over a length of an edge portion thereof. Blade 131 may be used for cutting, splitting, chopping, or the like, and may optionally include notch 132 for use in pulling nails, cutting or stripping wire, or the like. Accordingly, and similar to first projection 105 , second projection 107 is preferably adapted to withstand repeated impact forces without failure.
[0022] Additionally, second end 101 b preferably further includes at least one open-ended slot 133 between first and second projections 105 and 107 . As illustrated in FIG. 2 , slot 133 includes a first wider portion 135 and a second narrower portion 137 . Teeth 139 or other texture or friction surface is preferably provided on portions of second end 101 b proximate slot 133 , or at least one or more portion thereof, for enabling secure gripping engagement of tool 100 with a board or other member disposed within slot 133 . As will be understood by those skilled in the art, the sizes of wider portion 135 and narrower portion 137 may be selected to accommodate different sizes of dimensional lumber, metal studs, plywood, engineered lumber, composite members, or the like typically found or used in construction or demolition projects. As will further be understood by those ordinarily skilled in the art, wider portion 135 and narrower portion 137 of slot 133 may be replaced by separate slots 135 a and 137 a , as illustrated in FIG. 3 , wherein one or more of slots 135 a and 137 a may include varying or different dimension portions.
[0023] In use, tool 100 may be used to perform many different functions necessary for a selected job or task. For example, with regard to a demolition task, tool 100 may be used as a hammer wherein a user may hold tool 100 by grip 103 and swing second end 101 b to strike a desired object with hammer head 121 . Such striking may be useful in demolishing tile, masonry, metal, and/or wood structures, among others. When removing tile, hammer head 121 may be used to break a tile to remove it. Once the tile is removed, adjacent tiles may easily be removed by driving chisel 111 or blade 129 beneath the tile, whereby the tile may be pried loose either by a leverage action or by an increasing dimension of chisel 111 or blade 129 . Specifically, chisel 111 may be used as a second-class lever wherein the tip of chisel 111 acts as the fulcrum and wherein force is applied to grip 113 and/or second end 101 b. Claw 125 , however, may be used as a first-class lever wherein force is applied to grip 103 and/or first end 101 a and wherein a curved surface of claw 125 acts as a fulcrum to move blade 129 .
[0024] When desired tiles have been removed, tool 100 may further be employed to open a wall or floor to which the tiles were previously attached by striking with hammer head 121 blade 129 , blade 131 , and/or chisel 111 . Enclosed wires, pipes, or other conduits may likewise be demolished or removed by chopping with blade 131 or by striking with hammer head 121 . Structural members such as studs, beams, joists, or the like, may be removed by striking with hammer head 121 and/or by wrenching or torquing such members via grip 103 and/or first end 101 a and slot 133 . Nails or other fasteners projecting from removed members or remaining structures may be removed via slot 127 of claw 125 , via slot 119 , via notch 132 , or may be driven flush or bent flat via striking with hammer head 121 . Furthermore, any structures secured via bolts may be removed by disposing a bolt head or nut within a corresponding one of apertures 115 and 117 and by torquing via application of force to second end 101 b and/or grip 113 .
[0025] Thus, many different functions may be performed by tool 110 in order to accomplish a task without the need for additional tools. Accordingly, in many instances, tool 100 may be the only tool necessary to complete a selected task or job. As a result, such task or job may be finished more quickly due to the ability of a user to transition between different functions without having to stop, find a different tool, and resume work.
[0026] Having thus described exemplary embodiments of the present invention, it should be noted by those skilled in the art that the within disclosures are exemplary only and that various other alternatives, adaptations, and modifications may be made within the scope and spirit of the present invention. Accordingly, the present invention is not limited to the specific embodiments as illustrated herein, but is only limited by the following claims. | A multi-function tool having a handle portion and a plurality of structures operable therewith for the performance of a plurality of functions. The multi-function tool allows fast and convenient transition between any of the plurality of functions in order to enable completion of jobs or tasks requiring such functions without acquisition, storage, and/or maintenance of a plurality of specialized tools. | 4 |
FIELD OF THE INVENTION
The present invention relates to late transition metal complexes; a process for their preparation and their use in the polymerization of olefins.
BACKGROUND OF THE INVENTION
The papers Organometallics, 10, 1421-1431, 1991; Inorg. Chem., 34, 4092-4105, 1995; J. Organomet. Chem., 527(1-2), 263-276, 1997; and Inorg. Chem., 35(6), 1518-28, 1996, report the reaction of bis (iminophosphoranyl) methane (BIPM) which are typically aryl substituted on the phosphorus atom and the nitrogen with group VIII metal halides (chlorides) further comprising at two weakly coordinating ligands (L) such as nitriles or cyclooctadiene, afforded several products depending on the reaction time, type of ig and or nature of the metal. The product could be a N-C chelating type product or a N-N chelating product (similar to those of the present invention).
The products contain alkyl bridge between the phosphinimine groups and the references do not disclose the tridentate transition metal complexes of the present invention. Further, none of the references teach or suggest the use of such compounds for the polymerization of alpha olefins.
U.S. Pat. No. 5,557,023 issued September, 1996 teaches the use of some phosphinimines complexes to oligomerize alpha olefins. However, the complexes disclosed are not bis-imine complexes. Rather, the complexes are of the structure indicated below.
wherein R, Q, etc. are as defined in the patent. The structures disclosed in the patent are not the bis-imines of the present invention. While the reference does teach oligomerization, it does not suggest polymerization.
WO 98/30609 patent application published Jul. 16, 1998 assigned to E.I. Du Pont de Nemours teaches the use of various complexes of nickel to polymerize alpha olefins. A close complex in the disclosure is compound XXXXI at the middle of page 9 and the associated description of the various substituents. While, the compound contains a cyclic bridge, a nickel heteroatom completes the cyclic bridge in the middle of the compound. The reference does not contemplate or disclose compounds of the present invention which have a tridentate functionality. The reference fails to disclose the subject matter of the present invention.
There are a number of patents and papers by Brookhart and/or Gibson disclosing the use of pyridine bridged bis-amine Group 8, 9 or 10 metals to polymerize olefins. However, such papers teach that copolymers are not produced (e.g. WO 98/27124). The present invention proved copolymers of olefins made using an iron (or cobalt) based catalyst.
WO 98/47933 published Oct. 29, 1998 to MacKenzie et al, assigned to Eastman Chemical Company teaches bidentate amino-imine complexes of iron, cobalt, nickel and palladium for the polymerization of olefins. The complexes do not contemplate the presence of a sulfur, oxygen or phosphorus atom in the ligand bound to the iron, cobalt, nickel or palladium metal atom. As such the reference teaches away from the subject matter of the present invention.
WO 98/49208 published Nov. 5, 1998 in the name of Bres et al, assigned to BP Chemicals Limited also discloses an amino-imine complex of nickel or palladium for the polymerization of alpha olefins. Again the reference teaches away from the subject matter of the present invention in that it does not teach nor suggest the presence of a sulfur, oxygen or phosphorus atom bound to the metal atom in the complex.
SUMMARY OF THE INVENTION
The present invention provides a ligand of formula I:
wherein W is selected from the group consisting of a sulfur atom, an oxygen atom and a phosphorus atom; Y and Z are independently selected from the group consisting of a carbon atom, a phosphorus atom and a sulfur atom; when Y is phosphorus m is 2, when Y is carbon or sulfur m is 1; when Z is phosphorus n is 2, when Z is carbon or sulfur n is 1; each R is independently selected from the group consisting of a hydrogen atom, and a hydrocarbyl radical or R taken together with Q may form a cyclic hydrocarbyl; R 1 and R 2 are independently selected from the group consisting of a hydrogen atom, a substituted or unsubstituted hydrocarbyl radical which may contain one or more heteroatoms, preferably consisting of the group selected from silicon, boron, phosphorus, nitrogen and oxygen which may be bound directly or indirectly to the nitrogen atoms and a tri-C 14 alkyl silyl radical; Q is a divalent unsaturated hydrocarbyl radical or a divalent radical comprising hydrogen, carbon and one or more heteroatoms selected from the group consisting of an oxygen atom, a nitrogen atom, a sulfur atom and a boron atom, and Q when taken together with W forms one or more unsaturated rings, which unsaturated cyclic rings may be unsubstituted or may be fully substituted by one or more substituents independently selected from the group consisting of a halogen atom and an alkyl radical.
The present invention further provides a process for the polymerization of one or more C 2-12 alpha olefins in the presence of an activated complex of formula II:
wherein M is a Group 8, 9 or 10 metal; W is selected from the group consisting of a sulfur atom, an oxygen atom and a phosphorus atom; Y and Z are independently selected from the group consisting of a carbon atom, a phosphorus atom and a sulfur atom; when Y is phosphorus m is 2, when Y is carbon or sulfur m is 1; when Z is phosphorus n is 2, when Z is carbon or sulfur n is 1; each R is independently selected from the group consisting of a hydrogen atom, and a hydrocarbyl radical or R taken together with Q may form a cyclic hydrocarbyl; R 1 and R 2 are independently selected from the group consisting of a hydrogen atom, a substituted or unsubstituted hydrocarbyl radical which may contain one or more heteroatoms, preferably consisting of the group selected from silicon, boron, phosphorus, nitrogen and oxygen which may be bound directly or indirectly to the nitrogen atoms and a tri-C 1-4 alkyl silyl radical; Q is a divalent unsaturated hydrocarbyl radical or a divalent radical comprising hydrogen, carbon and one or more heteroatoms selected from the group consisting of an oxygen atom, a nitrogen atom, a sulfur atom and a boron atom, and Q when taken together with W one or more unsaturated rings, which unsaturated cyclic rings may be unsubstituted or may be fully substituted by one or more substituents independently selected from the group consisting of a halogen atom and an alkyl radical, L is an activatable ligand and p is an integer from 1 to 3.
In a further aspect, the present invention provides a process for reacting one or more C 2-12 alpha olefins in a nonpolar solvent in the presence of the above catalyst with an activator at a temperature from 20° C. to 250° C.; and at a pressure from 15 to 15000 psi.
DETAILED DESCRIPTION
The term “scavenger” as used in this specification is meant to include those compounds effective for removing polar impurities from the reaction solvent. Such impurities can be inadvertently introduced with any of the polymerization reaction components, particularly with solvent, monomer and catalyst feed; and can adversely affect catalyst activity and stability. It can result in decreasing or even elimination of catalytic activity, particularly when an activator capable of ionizing the Group 8, 9 or 10 metal complex is also present.
The term “an inert functional group” means a functional group on a ligand or substituent which does not participate or react in the reaction. For example in the polymerization aspect of the present invention an inert functional group would not react with any of the monomers, the activator or the scavenger of the present invention. Similarly for the alkylation of the metal complex or the formation of the metal complex the inert functional group would not interfere with the alkylation reaction or the formation of the metal complex respectively.
As used in this specification an activatable ligand is a ligand removed or transformed by an activator. These include anionic substituents and/or bound ligands.
In the compounds of formula II above, preferably M is a Group 8, 9 or 10 metal. Preferably M is selected from the group of Group 8, 9 or 10 metals consisting of Fe, Co, Ni or Pd.
In the above compounds of formula I and II, each R is independently selected from the group consisting of a hydrogen atom and hydrocarbyl radical. Preferably R is selected from the group consisting of C 1-10 alkyl or aryl radicals, most preferably C 1-4 radicals such as a bulky t-butyl radical and phenyl radicals. In the above formula I and II, R 1 and R 2 are independently selected from the group consisting of a hydrocarbyl radical preferably a phenyl radical which is unsubstituted or substituted by up to five hydrocarbyl radicals which may contain one or more inert functional groups, preferably C 1-4 alkyl radicals, or a C 1-10 alkyl radical, or two hydrocarbyl radicals taken together may form a ring, or tri alkyl silyl radical, preferably C 1-6 , most preferably C 1-4 silyl radical. Preferably R may be a 2,6-diisopropyl phenyl radical or a trimethyl silyl radical. In the complex of formula II above, L is an activatable ligand preferably a halide atom or a C 1-6 alkyl or alkoxide radical, most preferably a halide atom (Cl or Br) and p is from 1 to 3, preferably 2 or 3.
In the compounds of formula I and II, the unsaturated rings structure formed by Q taken together with W may form one or more a 5 to 10 membered ring(s)(i.e. Q contains from 4 to 9 atoms). As noted above not all of the atoms in the backbone of Q need to be carbon atoms. Q may contain one or more heteroatoms selected from the group consisting of an oxygen atom, a nitrogen atom, a sulfur atom and a boron atom. The resulting ring structure may be unsubstituted or up to fully substituted by one or more substituents selected from the group consisting of a halogen atom, preferably chlorine and a C 1-4 alkyl radical.
In the above formulas I and II, R may be taken together with Q to form a cyclic hydrocarbyl structure, preferably an aromatic ring. If W is a sulfur atom then Q taken with the W may form rings such as thiophene, dithiole, thiazole and thiepin. If Q taken together with one R forms a cyclic hydrocarbyl then the structure may be benzothiophene. These unsaturated rings may be unsubstituted or up to fully substituted by one or more substituents selected from the group consisting of a halogen atom, preferably chlorine and a C 1-4 alkyl radical.
If W is an oxygen atom then Q taken with the W may form rings such as furan, oxazole, oxidiazole, pyran, dioxin, oxazine and oxepin. If Q taken together with one R forms a cyclic hydrocarbyl then the structure may be benzofuran, benzoxazole and benzoxazine. If both R's are taken together with Q and W the structure could be xanthene. These unsaturated rings may be unsubstituted or up to fully substituted by one or more substituents selected from the group consisting of a halogen atom, preferably chlorine and a C 1-4 alkyl radical.
If W is a phosphorus atom then the phosphorus homologues of the above oxygen and sulfur rings would be obtained.
In the above compounds, Z and Y may independently be selected from the group consisting of a carbon atom, an oxygen atom or a phosphorus atom. Preferably Z and Y are the same. Most preferably Z and Y are phosphorus atoms.
The metal complexes of the present invention may be prepared by reacting the ligand with a compound of MX n . A (H 2 O), where X may be selected from the group consisting of halogen, C 1-6 alkoxide, nitrate or sulfate, preferably halide and most preferably chloride or bromide, and A is 0 or an integer from 1-6.
The reaction of the complex of formula I with the compound of the formula MX n . A (H 2 O) may be conducted in a hydrocarbyl solvent or a polar solvent such as THF (tetrahydrofuran) or dichloromethane at temperature from 20° C. to 250° C., preferably from 20° C. to 120° C.
The resulting compound (i.e. formula II) may then be alkylated (either partially or fully). Some alkylating agents include alkyl aluminum reagents such as trialkyl aluminum, alkyl aluminum halides (i.e. (R) x AlX 3−x wherein R is a C 1-10 alkyl radical, X is a halogen, x is 1 or 2 and MAO as described below).
Solution polymerization processes are fairly well known in the art. These processes are conducted in the presence of an inert hydrocarbon solvent typically a C 5-12 hydrocarbon which may be unsubstituted or substituted by C 1-4 alkyl group such as pentane, hexane, heptane, octane, cyclohexane, methylcyclohexane or hydrogenated naphtha. An additional solvent is Isopar E (C 8-12 aliphatic solvent, Exxon Chemical Co.).
The polymerization may be conducted at temperatures from about 20° C. to about 250° C. Depending on the product being made, this temperature may be relatively low such as from 20° C. to about 180° C. The pressure of the reaction may be as high as about 15,000 psig for the older high pressure processes or may range from about 15 to 4,500 psig.
Suitable olefin monomers may be ethylene and C 3-20 mono- and di-olefins. Preferred monomers include ethylene and C 3-12 alpha olefins which are unsubstituted or substituted by up to two C 1-6 alkyl radicals, C 8-12 . Illustrative non-limiting examples of such alpha olefins are one or more of propylene, 1-butene, 1-pentene, 1-hexene, 1-octene and 1-decene.
The reaction product of the present invention may be a co- or homopolymer of one or more alpha olefins. The polymers prepared in accordance with the present invention have a good molecular weight. That is, weight average molecular weight (Mw) will preferably be greater than about 50,000 ranging up to 10 6 , preferably 10 5 to 10 6 .
The polyethylene polymers which may be prepared in accordance with the present invention typically comprise not less than 60, preferably not less than 70, most preferably not less than 80, weight % of ethylene and the balance of one or more C 4-10 alpha olefins, preferably selected from the group consisting of 1-butene, 1-hexene and 1-octene. The polyethylene prepared in accordance with the present invention may contain branching (e.g. one or more branches per 1000 carbon atoms, preferably 1-20 branches per 1000 carbon atoms, typically 1-10 branches per 1000 carbon atoms.
The activator may be selected from the group consisting of:
(i) an aluminoxane; and
(ii) an activator capable of ionizing the Group 8, 9 or 10 metal complex (which may be used in combination with an alkylating activator).
The aluminoxane activator may be of the formula (R 20 ) 2 AlO(R 20 AlO) m Al(R 20 ) 2 wherein each R 20 is independently selected from the group consisting of C 1-20 hydrocarbyl radicals, m is from 0 to 50, and preferably R 20 is a C 1-4 alkyl radical and m is from 5 to 30. The aluminoxane activator may be used prior to the reaction but preferably in situ alkylation is typical (e.g. alkyl groups replacing leaving ligands, hydrogen or halide groups).
If the Group 8, 9 or 10 metal complex is activated only with aluminoxane, the amount of aluminoxane will depend on the reactivity of the alkylating agent. Activation with aluminoxane generally requires a molar ratio of aluminum in the activator to the Group 8, 9 or 10 metal in the complex from 50:1 to 1000:1. MAO may be at the lower end of the above noted range.
The activator of the present invention may be a combination of an alkylating activator which also serves as a scavenger other than aluminoxane in combination with an activator capable of ionizing the Group 8, 9 or 10 complex.
The alkylating activator (which may also serve as a scavenger) may be selected from the group consisting of: (R) p MgX 2-p wherein X is a halide, each R is independently selected from the group consisting of C 1-10 alkyl radicals, preferably C 1-8 alkyl radicals and p is 1 or 2; RLi wherein R is as defined above; (R) q ZnX 2-q wherein R is as defined above, X is halogen and q is 1 or 2; (R) s AlX 3-s wherein R is as defined above, X is halogen and s is an integer from 1 to 3. Preferably in the above compounds, R is a C 1-4 alkyl radical and X is chlorine. Commercially available compounds include triethyl aluminum (TEAL), diethyl aluminum chloride (DEAC), dibutyl magnesium ((Bu) 2 Mg) and butyl ethyl magnesium (BuEtMg or BuMgEt).
The activator capable of ionizing the Group 8, 9 or 10 metal complex may be selected from the group consisting of:
(i) compounds of the formula [R 15 ] + [B(R 18 ) 4 ] − wherein B is a boron atom, R 15 is a cyclic C 5-7 aromatic cation or a triphenyl methyl cation and each R 18 is independently selected from the group consisting of phenyl radicals which are unsubstituted or substituted with from 3 to 5 substituents selected from the group consisting of a fluorine atom, a C 1-4 alkyl or alkoxy radical which is unsubstituted or substituted by a fluorine atom; and a silyl radical of the formula—Si-(R 19 ) 3 wherein each R 19 is independently selected from the group consisting of a hydrogen atom and a C 1-4 alkyl radical; and
(ii) compounds of the formula [(R 16 ) t ZH] + [B(R 18 ) 4 ] − wherein B is a boron atom, H is a hydrogen atom, Z is a nitrogen atom or phosphorus atom, t is 2 or 3 and R 16 is selected from the group consisting of C 1-8 alkyl radicals, a phenyl radical which is unsubstituted or substituted by up to three C 1-4 alkyl radicals, or one R 16 taken together with the nitrogen atom to form an anilinium radical and R 18 is as defined above; and
(iii) compounds (activators) of the formula B(R 18 ) 3 wherein R 18 is as defined above.
In the above compounds preferably R 18 is a pentafluorophenyl radical, R 15 is a triphenylmethyl cation, Z is a nitrogen atom and R 16 is a C 1-4 alkyl radical or R 16 taken together with the nitrogen atom forms an anilinium radical which is substituted by two C 1-4 alkyl radicals.
The activator capable of ionizing the Group 8, 9 or 10 metal complex abstracts one or more L 1 ligands so as to ionize the Group 8, 9 or 10 metal center into a cation, but not to covalently bond with the Group 8, 9 or 10 metal, and to provide sufficient distance between the ionized Group 8, 9 or 10 metal and the ionizing activator to permit a polymerizable olefin to enter the resulting active site.
Examples of compounds capable of ionizing the Group 8, 9 or 10 metal complex include the following compounds:
triethylammonium tetra(phenyl)boron,
tripropylammonium tetra(phenyl)boron,
tri(n-butyl)ammonium tetra(phenyl)boron,
trimethylammonium tetra(p-tolyl)boron,
trimethylammonium tetra(o-tolyl)boron,
tributylammonium tetra(pentafluorophenyl)boron,
tributylammonium tetra(pentafluorophenyl)boron,
tri(n-butyl)ammonium tetra(o-tolyl)boron
N,N-dimethylanilinium tetra(phenyl)boron,
N,N-diethylanilinium tetra(phenyl)boron,
N,N-diethylanilinium tetra(phenyl)n-butylboron,
N,N-2,4,6-pentamethylanilinium tetra(phenyl)boron
di-(isopropyl)ammonium tetra(pentafluorophenyl)boron,
dicyclohexylammonium tetra (phenyl)boron
triphenylphosphonium tetra)phenyl)boron,
tri(methylphenyl)phosphonium tetra(phenyl)boron,
tri(dimethylphenyl)phosphonium tetra(phenyl)boron,
tropillium tetrakispentafluorophenyl borate,
triphenylmethylium tetrakispentafluorophenyl borate,
benzene (diazonium) tetrakispentafluorophenyl borate,
tropillium phenyltris-pentafluorophenyl borate,
triphenylmethylium phenyl-trispentafluorophenyl borate,
benzene (diazonium) phenyltrispentafluorophenyl borate,
tropillium tetrakis (2,3,5,6-tetrafluorophenyl) borate,
triphenylmethylium tetrakis (2,3,5,6-tetrafluorophenyl) borate,
benzene (diazonium) tetrakis (3,4,5-trifluorophenyl) borate,
tropillium tetrakis (3,4,5-trifluorophenyl) borate,
benzene (diazonium) tetrakis (3,4,5-trifluorophenyl) borate,
tropillinum tetrakis (1,2,2-trifluoroethenyl) borate,
triphenylmethylium tetrakis (1,2,2-trifluoroethenyl) borate,
benzene (diazonium) tetrakis (1,2,2-trifluoroethenyl) borate,
tropillium tetrakis (2,3,4,5-tetrafluorophenyl) borate,
triphenylmethylium tetrakis (2,3,4,5-tetrafluorophenyl) borate, and
benzene (diazonium) tetrakis (2,3,4,5-tetrafluorophenyl) borate.
Readily commercially available activators which are capable of ionizing the Group 8, 9 or 10 metal complexes include:
N,N- dimethylaniliniumtetrakispentafluorophenyl borate;
triphenylmethylium tetrakispentafluorophenyl borate; and
trispentafluorophenyl boron.
If the Group 8, 9 or 10 metal complex is activated with a combination of an aluminum alkyl compound (generally other than aluminoxane), and a compound capable of ionizing the Group 8, 9 or 10 metal complex (e.g. activators (I) and (III) above) the molar ratios of Group 8, 9 or 10 metal:metal in the alkylating agent (e.g. Al); metalloid (e.g. boron or phosphorus) in the activator capable of ionizing the Group 8, 9 or 10 metal complex (e.g. boron) may range from 1:1:1 to 1:100:5. Preferably, the alkylating activator is premixed/reacted with the Group 8, 9 or 10 metal complex and the resulting alkylated species is then reacted with the activator capable of ionizing the Group 8, 9 or 10 metal complex.
In a solution polymerization the monomers are dissolved/dispersed in the solvent either prior to being fed to the reactor, or for gaseous monomers, the monomer may be fed to the reactor so that it will dissolve in the reaction mixture. Prior to mixing, the solvent and monomers are generally purified to remove polar moieties. The polar moieties or catalyst poisons include water, oxygen, metal impurities, etc. Preferably steps are taken before provision of such into the reaction vessel, for example by chemical treatment or careful separation techniques after or during the synthesis or preparation of the various components. The feedstock purification prior to introduction into the reaction solvent follows standard practices in the art (e.g. molecular sieves, alumina beds and oxygen removal catalysts) are used for the purification of ethylene, alpha olefin and optional diene. The solvent itself as well (e.g. cyclohexane and toluene) is similarly treated. In some instances, out of an abundance of caution, excess scavenging activators may be used in the polymerization process.
The feedstock may be heated prior to feeding into the reactor. However, in many instances it is desired to remove heat from the reactor so the feed stock may be at ambient temperature to help cool the reactor.
Generally, the catalyst components may be premixed in the solvent for the reaction or fed as separate streams to the reactor. In some instances premixing is desirable to provide a reaction time for the catalyst components prior to entering the reaction. Such an “in line mixing” technique is described in a number of patents in the name of Novacor Chemicals (International) S.A. (now known as NOVA Chemicals (International) S.A.) acquired from DuPont Canada Inc. For example it is described in U.S. Pat. No. 5,589,555 issued Dec. 31, 1996.
The reactor may comprise a tube or serpentine reactor used in the “high pressure” polymerizations or it may comprise one or more reactors or autoclaves. It is well known that the use in series of two such reactors each of which may be operated so as to achieve different polymer molecular weight characteristics. The residence time in the reactor system will depend on the design and the capacity of the reactor. Generally the reactors should be operated under conditions to achieve a thorough mixing of the reactants. On leaving the reactor system the solvent is removed and the resulting polymer is finished in a conventional manner.
The present invention will now be illustrated by the following examples in which unless otherwise specified weight means weight % and parts means parts by weight (e.g. grams).
EXAMPLES
Materials:
2,6-dibromothiophene, diphenylphosphine (Ph 2 PH), di-tert-butylphosphine chloride (t-Bu 2 PCl), 2,5-Bis(5-tert-butyl-2-benzoxazolyl)thiophene (IIf), 2,6-di-iso-propylaniline, 2,5-thiophenedicarboxaldehyde, iron (II) chloride (FeCl 2 ), iron (III) chloride (FeCl 3 ), cobalt chloride (CoCl 2 ), nickel (II) bromide (NiBr 2 ), n-Butyl lithium (n-BuLi, 1.6M in hexane), and trimethylsilyl azide (TMSN 3 ) were purchased from Aldrich Chemical Company Inc., Strem Chemical Inc. or Fisher Scientific. Solvents were prepared by passing through molecular sieves, de-oxo catalysts and alumina columns prior to use. Methylaluminoxane (PMAO-IP) (13.5 weight % of Al) was purchased from AKZO-NOBEL. Diimine-ferrous complex (VII) was synthesized as described in the literature (G. L. P. Britovsek, V. C. Gibson, B. S. Kimberley, P. J. Maddox, S. J. McTavish, G. A. Solan, A. J. P. White and D. J. Williams, J. Chem. Soc. Chem. Commun., 1998, 849 and B. L. Small, M. Brookhart and A. M. A. Bennett, J. Am. Chem. Soc., 120, 4049, 1998). The anhydrous toluene was purchased from Aldrich and purified over molecular sieves prior to use. B(C 6 F 5 ) 3 was purchased from Boulder Scientific Inc. and used without further purification. Trityl borate was purchased from Asahi Glass Inc., lot #980224.
Measurements:
NMR spectra were recorded using a Bruker 200 MHz spectrometer. 1 H NMR chemical shifts were reported with reference to tetramethylsilane. Polymer molecular weights and molecular weight distributions were measured by GPC (Waters 150-C) at 140° C. in 1,2,4-trichlorobenzene calibrated using polyethylene standards. DSC was conducted on a DSC 220 C from Seiko Instruments. The heating rate is 10° C./minute from 0 to 200° C. FT-IR was conducted on a Nicolet Model 750 Magna IR spectrometer.
Operation:
All synthesis and catalyst preparations were performed under nitrogen or argon atmospheres using standard Schienk techniques or in a dry-box.
Example 1
Synthesis of Bis(2,5-di-tert-butvlphosphino)thiophene (Ia)
To a THF (50 mL) solution of 2,5-dibromothiophene (5.00 g, 20.7 mmol) at −78° C. was added slowly a THF (30 mL) solution of n-BuLi (26.9 mL, 1.6 M in hexane, 41.3 mmol). The color of the solution changed from clear colorless to pale blue, then to pink, then to green. After 95% BuLi addition, the greenish solution gelated. The reaction mixture was then allowed to warm to −50° C. over 1 hour and a THF (25 mL) solution of t-Bu 2 PCl (7.47 g, 41.3 mmol) was added. The color of the reaction solution changed to pale yellow. The reaction mixture was warmed to room temperature and stirred for 12 hours. All volatiles were then removed under vacuum. The resulting residue was dissolved in heptane (50 mL) and LiBr was removed by filtration. When the heptane and some volatile impurities were removed at 50° C. in vacuo, a brown solid was obtained. The pure product, a pale pink solid, was obtained from a crystallization process in a hexane/toluene (3:1) solution at −35° C. Yield is 36%. 1 H NMR (toluene-d 8 , δ): 1.20 (d, J=11.8 Hz, 36H), 7.34-7.38 (m, 2H). The purity and molecular weight (M + =372) were confirmed by GC-MS.
Example 2
Synthesis of 2,5-bis (diphenylphosphino)thiophene (Ib)
A THF (50 mL) solution of diphenylphosphine (2.53 g, 13.6 mmol) was treated with n-BuLi (8.5 mL, 1.6 M, 13.6 mmol) using a drop-wise addition. The reaction mixture was allowed to stir 20 minutes and was then added to a solution of 2,5-dibromothiophene (1.63 g, 6.79 mmol) at room temperature resulting in a yellow solution. The reaction was allowed to warm up to room temperature for 2 hours. The product (2.92 g, 95% yield) was purified by a crystallization process in toluene. 1 H NMR (toluene-d 8 , δ): 7.02-6.97 (m, 12H), 7.12-7.09 (m, 2H), 7.30-7.39 (m, 8H). The purity and molecular weight (M + =452) were confirmed by GC-MS.
Example 3
Synthesis of 2,5-(t-Bu 2 P=NTMS) 2 thiophene (IIa)
A 200 mL Schlenk flask was fitted with a condenser, a nitrogen inlet, a gas outlet bubbler and a TMSN 3 addition line. The flask was charged with 2,5-(t-Bu 2 P) 2 thiophene (Ia) (1.29 g, 3.47 mmol). The TMSN 3 line was charged with TMSN 3 (7.0 mL, 52.7 mmol) through a syringe. At room temperature, 3 mL of TMSN 3 was injected into the flask and the mixture was heated to 95° C. The remaining TMSN 3 was added to the reaction at 95° C. As the addition occurred, nitrogen was evolved. After the addition was completed, the reaction mixture was kept for an additional 2 hours at 110° C. When the excess of TMSN 3 was removed under vacuum, a white solid (1.87 g, 98% yield) was obtained. 1 H NMR (toluene-d 8 , δ): 0.43 (s, 18H), 1.12 (d, J=14.7 Hz, 36H), 7.34-7.38 (m, 2H).
Example 4
Synthesis of 2,5-(Ph2P=NTMS) 2 thiophene (IIb)
A 200 mL Schlenk flask was fitted with a condenser, a nitrogen inlet, a gas outlet bubbler and a TMSN 3 addition line. The flask was charged with 2,5-(Ph 2 P) 2 thiophene (Ib) (2.92 g, 6.45 mmol). The TMSN 3 line was charged with TMSN 3 (6.0 mL, 45.2 mmol) through a syringe. At room temperature, 3 mL of TMSN 3 was injected into the flask and the mixture was heated to 95° C. The remaining TMSN 3 was added to the reaction at 95° C. As the addition occurred, nitrogen was evolved. After the addition was completed, the reaction mixture was kept for an additional 2 hours at 115° C. When the excess of TMSN 3 was removed under vacuum, a white solid (4.0 g, 98% yield) was obtained. 1 H NMR (toluene-d 8 , δ): 0.31 (s, 18H), 6.99-7.04 (m, 12H), 7.11-7.23 (m, 2H), 7.64-7.74 (m, 8H).
Example 5
Synthesis of 2,5-(Ph 2 P=N-PBu t 2 )thiophene (IIc)
The toluene solution of IIb (200 mg, 0.37 mmol) and chlorodiphenylphosphine (169 mg, 0.76 mmol) was refluxed for 25 hours. When the toluene was removed in vacuo, a pale yellow solid (280 mg, 99% yield) was obtained. 1 H NMR (toluene-d 8 , δ): 1.25 (d, J=10.6, 36H), 6.92-7.04 (m, 12H), 7.54-7.65 (m, 8H), 8.50-8.60 (m, 2H).
Example 6
Synthesis of 2,5-(Ph 2 P=N-P(Bu t 2 )=NTMS) 2 thiophene (IId)
A 200 mL Schienk flask was fitted with a condenser, a nitrogen inlet, a gas outlet bubbler and a TMSN 3 addition line. The flask was charged with 2,5-(Ph 2 P=N-P(Bu t 2 )) 2 thiophene (IIc) (0.28 g, 0.37 mmol). The TMSN 3 line was charged with TMSN 3 (2.5 mL, 18.8 mmol) through a syringe. At room temperature, 1 mL of TMSN 3 was injected into the flask and the mixture was heated to 95° C. The remaining TMSN 3 was added to the reaction at 95° C. As the addition occurred, nitrogen was evolved. After the addition was completed, the reaction mixture was kept for an additional 2 hours at 115° C. When the excess of TMSN 3 was removed under vacuum, a pale yellow solid (0.33 g, 95% yield) was obtained. 1 H NMR (toluene-d 8 , δ): 0.33 (s, 18H), 1.15 (d, J=10.3 Hz, 36H), 6.97-7.10 (m, 12H), 7.11-7.23 (m, 8H), 8.07-8.25 (m, 2H).
Example 7
Synthesis of 2,5-thiophenedicarboxaldehydebis(2,6-diisopropyl)phenVl) (IIe)
In a 500 mL Schlenk flask, 2,5-thiophenedicarboxaldehyde (2 g, 14.3 mmol), 2,6-diisopropylaniline (5.13 g, 29 mmol) and formic acid (1 mL) were placed in methanol (100 mL). The mixture was stirred at room temperature overnight. A yellow solid (4.5 g, yield 91 %) was obtained when the reaction mixture was filtered off, washed with MeOH and dried. 1 H NMR (toluene-d 8 , δ): 1.21 (d, J=6.9 Hz, 24H), 3.02 (m, 4H), 7.1-7.2 (m, 6H), 7.49 (s, 2H), 8.30 (s, 2H).
Examples 8-13
Synthesis of Catalyst Precursors
General Procedure: The ligand (2,5-(t-Bu 2 P=NTMS) 2 thiophene (IIa), 1 eq.) and a metal salt (FeCl 2 , CoCl 2 , FeBr 3 , FeCl 3 or NiBr 2 ) were added together in a Schienk flask in a dry-box. Then the flask was charged with THF (30 mL) or dichloromethane (CH 2 Cl 2 , 30 mL). The mixture was stirred for several hours until no metal salts were observed in the flask. The reaction solution was filtered to remove some insoluble polymeric materials and was concentrated. Heptane (5 mL) was added to precipitate the complex. The resultant solid was filtered and washed with heptane and dried in vacuo.
Example 8
Fe(III) Complex (IIIa) from IIa and FeCl 3
Isolated as a beige solid (Yield: 98%). 1 H NMR (toluene-d8, δ): 0.42 (s, br, 18H), 1.12 (d, br, J=14.7 Hz, 36H), 7.37 (s, br, 2H).
Example 9
Fe(II) Complex (IIIb) from IIa and FeCl 2
Isolated as a white solid (Yield: 85%). 1 H NMR (THF-d8, all peaks appear as singlets due to their broadness, δ): 0.09 (s, br, 18H), 1.25 (d, J=14.6 Hz, 36H), 7.65 (s, br, 2H).
Example 10
Co(II) Complex (IIIc) from IIa and CoCl 2
Isolated as a blue solid (Yield: 100%). 1 H NMR (THF-d8, all peaks appear as singlets due to their broadness, δ): 0.09 (s, br, 18H), 1.25 (d, br, J=14.8 Hz, 36H), 7.65 (s, br, 2H).
Example 11
Fe(III) Complex (IV) from IId and FeCl 3
Isolated as a pale amber solid (Yield: 84%). 1 H NMR (THF-d8, δ): −0.10 (s, 18H), 1.29 (br, 36H), 7.20 (s, br, 12H), 7.77 (s, br, 8H).
Example 12
Fe(III) Complex (V) from IIe and FeCl 2
Isolated as an yellow solid (Yield: 98%). 1 H NMR (THF-d8, all peaks appear as singlets due to their broadness, δ): 1.13 (br, 24H), 3.1 (br, 4H), 7.08 (br, 8H), 7.9 (s, br, 2H).
Example 13
Fe(III) Complex (VI) from IIf and FeBr 3
Isolated as an yellow solid (Yield: 98%). 1 H NMR (THF-d8, all peaks appear as singlets due to their broadness, δ): 0.62 (s, br), 6.15 (s, br).
Polymerization Results
In the examples, the pressures given are gauge pressures. The following abbreviations and terms are used:
Branching: reported as the number of methyl groups per 1000 methylene groups in the polymer. It is determined by FT-IR.
Polydispersity: weight average molecular weight (Mw) divided by number average molecular weight (Mn).
DSC: differential scanning calorimetry.
GPC: gel permeation chromatography.
MeOH: methanol.
PMAO-IP: a type of polymethylaluminoxane.
All the polymerization experiments described below were conducted using a 500 mL Autoclave Engineers Zipperclave reactor. All the chemicals (solvent, catalyst and cocatalyst) were fed into the reactor batchwise except ethylene which was fed on demand. No product was removed during the polymerization reaction. As are known to those skilled in the art, all the feed streams were purified prior to feeding into the reactor by contact with various absorption media to remove catalysts killing impurities such as water, oxygen, sulfur and polar materials. All components were stored and manipulated under an atmosphere of purified argon or nitrogen. The reactor uses a programmable logic control (PLC) system with Wonderware 5.1 software for the process control. Ethylene polymerizations were performed in the reactor equipped with an air driven stirrer and an automatic temperature control system.
Polymerization temperature was 50° C. for slurry polymerizations and 140 and 160° C. for solution polymerizations. The polymerization reaction time varied from 10 to 30 minutes for each experiment. The reaction was terminated by adding 5 mL of methanol to the reactor and the polymer was recovered by evaporation of the toluene. The polymerization activities were calculated based on weight of the polymer produced.
Slurry Polymerization
Example 14
The Iron Complex (IIIa) With MAO Activation
Toluene (216 mL) was transferred into the reactor. The solvent was heated to 50° C. and saturated with 300 psig of ethylene. PMAO-IP (3.83 mmol, 0.85 mL) was first injected into the reactor. After one minute, the catalyst (IIIa) (64.8 umol, 46.1 mg) dissolved in toluene (12.2 mL) was injected into the reactor. The polymerization happened slowly with no temperature increase. The reaction was terminated by adding 5 mL of MeOH after 30 minutes. The polymer was dried.
Yield=2.6 g. Activity=80.0 gPE/mmolicat*hr. Mw=353.7*10 3 . PD=3.5. Tm=133.0° C.
Solution Polymerization
Example 15
The Iron Complex (IIa) With MAO Activation
Toluene (216 mL) was transferred into the reactor. The solvent was heated to 140° C. and saturated with 286 psig of ethylene. PMAO-IP (3.83 mmol, 0.85 mL) was first injected into the reactor. After one minute, the catalyst (IIIa) (64.8 umol, 45.9 mg) dissolved in toluene (12.2 mL) was injected into the reactor. The polymerization happened immediately and reaction temperature increased to 147° C. within 30 seconds. The polymerization activity decreased dramatically after 1.5 minutes. The reaction was terminated by adding 5 mL of MeOH after 10 minutes. The polymer was dried.
Yield=5.1 g. Activity=473.0 g PE/mmolcat*hr. Mw=470.3*10 3 . PD=1.9. Tm=135.80° C.
Example 16
The Iron Complex (IIIa) With MAO Activation
Toluene (216 mL) was transferred into the reactor. The solvent was heated to 160° C. and saturated with 200 psig of ethylene. PMAO-IP (2.6 mmol, 0.60 mL) was first injected into the reactor. After one minute, the catalyst (IIIa) (43.2 umol, 30.6 mg) dissolved in toluene (12.2 mL) was injected into the reactor. The polymerization happened immediately and with no temperature increase. The polymerization activity decreased dramatically after 30 seconds. The reaction was terminated by adding 5 mL of MeOH after 10 minutes. The polymer was dried.
Yield=3.3 g. Activity=458.5 g PE/mmolcat*hr. Mw=560.8*10 3 . PD=2.6. Tm=132.9° C.
Example 17
The Iron Complex (IIIa) With MAO In-Situ Alkylation And B(C 6 F 5 ) 3 Activation
Toluene (216 mL) was transferred into the reactor with 0.05 mL of PMAO-IP (216.0 umol) in 10 mL of toluene. The solution was heated to 140° C. and saturated with 286 psig of ethylene. The catalyst (IIIa) (64.8 umol, 45.8 mg) was dissolved in toluene (11.8 mL) and transferred into a catalyst injection bomb and then mixed with PMAO-IP (1.35 mmol, 0.3 mL). B(C 6 F 5 ) 3 (67.9 umol, 34.8 mg) was dissolved in toluene (12.4 mL) and loaded into a cocatalyst injection bomb. The catalyst and cocatalyst were injected into reactor simultaneously. The polymerization happened immediately with no temperature increase. The ethylene consumption was decreased after 30 seconds and dropped to zero after 2 minutes. The reaction was terminated by adding 5 mL of MeOH after 10 minutes. The polymer was dried.
Yield=9.7 g. Activity=900.3 g PE/mmolcat*hr. Mw=495.9*10 3 . PD=2.1. Tm=134.7° C.
Example 18
The Iron Complex (IIIa) With MAO In-Situ Alkylation And [CPh 3 ][B(C 6 F 5 ) 4 ] Activation
Toluene (216 mL) was transferred into the reactor with 0.05 mL of PMAO-IP (216.0 umol) in 10 mL of toluene. The solution was heated to 140° C. and saturated with 286 psig of ethylene. The catalyst (IIIa) (64.8 umol, 45.5 mg) was dissolved in toluene (11.8 mL) and transferred into a catalyst injection bomb and then mixed with PMAO-IP (1.35 mmol, 0.3 mL). [CPh 3 ][B(C 6 F 5 ) 4 ] (68.0 umol, 62.3 mg) was dissolved in toluene (12.4 mL) and loaded into a cocatalyst injection bomb. The catalyst and cocatalyst were injected into reactor simultaneously. The polymerization happened immediately and polymerization temperature increased to 170° C. within 30 seconds. The polymerization activity decreased after 3 minutes. The reaction was terminated by adding 5 mL of MeOH after 10 minutes. The polymer was dried.
Yield=10.0 g. Activity=934.9 g PE/mmolcat*hr. Mw=749.3*10 3 . PD=2.0. Tm=134.3° C.
Example 19
The Iron Complex (IIIa) With MAO Activation For Ethylene And 1-Octene Copolymerization
Toluene (216 mL) and 40 mL of 1-octene were transferred into the reactor with 0.05 mL of PMAO-IP (216.0 umol) in 10 mL of toluene. The solution was heated to 140° C. and saturated with 286 psig of ethylene. PMAO-IP (3.83 mmol, 0.85 mL) was injected into the reactor. After one minute, the catalyst (IIIa) (64.8 umol, 45.6 mg) was dissolved in toluene and injected to the reactor. The polymerization happened immediately and polymerization temperature increased to 150° C. within 30 seconds. The reaction was terminated by adding 5 mL of MeOH after 10 minutes. The polymer was dried.
Yield=6.0 g. Activity=555.0 g PE/mmolcat*hr. Mw=790.7*10 3 . PD=2.0. Tm=115° C. 6.8 Br/1000° C. detected by FT-IR.
Example 20
The Iron Complex (IIIb) With MAO Activation
Toluene (216 mL) was transferred into the reactor. The solvent was heated to 140° C. and saturated with 286 psig of ethylene. PMAO-IP (3.83 mmol, 0.85 mL) was first injected into the reactor. After one minute, the catalyst (IIIb) (64.8 umol, 43.7 mg) dissolved in toluene (12.2 mL) was injected into the reactor. The polymerization happened immediately and reaction temperature increased to 145° C. within 30 seconds. The polymerization activity decreased dramatically after 1 minutes. The reaction was terminated by adding 5 mL of MeOH after 10 minutes. The polymer was dried.
Yield=3.7 g. Activity=342.4 g PE/mmolcat*hr. Mw=975.6*10 3 . PD=1.7. Tm=135.1° C.
Example 21
The Cobalt Complex (IIIc) With MAO Activation
Toluene (216 mL) was transferred into the reactor. The solvent was heated to 140° C. and saturated with 286 psig of ethylene. PMAO-IP (3.83 mmol, 0.85 mL) was first injected into the reactor. After one minute, the catalyst (IIIc) (64.8 umol, 43.7 mg) dissolved in toluene (12.2 mL) was injected into the reactor. The polymerization happened slowly with no temperature increase. The polymerization activity decreased dramatically after 2 minutes. The reaction was terminated by adding 5 mL of MeOH after 10 minutes. The polymer was dried.
Yield=3.8 g. Activity=351.4 g PE/mmolcat*hr. Mw=605.7*10 3 . PD=1.85. Tm=134.3° C.
Example 22
The Iron Complex (V) With MAO Activation
Toluene (216 mL) was transferred into the reactor. The solvent was heated to 140° C. and saturated with 286 psig of ethylene. PMAO-IP (3.83 mmol, 0.85 mL) was first injected into the reactor. After one minute, the catalyst (V)(64.8 umol, 38.0 mg) dissolved in toluene (12.2 mL) was injected into the reactor. The polymerization happened immediately and reaction temperature increased to 145° C. within 30 seconds. The polymerization activity decreased dramatically after 1 minute. The reaction was terminated by adding 5 mL of MeOH after 10 minutes. The polymer was dried.
Yield=3.5 g. Activity=322.9 g PE/mmolcat*hr. Mw=617.3*10 3 . PD=2.46. Tm=134.8° C.
Example 23
The Iron Complex (VI) With MAO Activation
Toluene (216 mL) was transferred into the reactor. The solvent was heated to 140° C. and saturated with 286 psig of ethylene. PMAO-IP (3.83 mmol, 0.85 mL) was first injected into the reactor. After one minute, the catalyst (VI) (64.8 umol, 46.9 mg) dissolved in toluene (12.2 mL) was injected into the reactor. The polymerization happened immediately and reaction temperature increased to 150° C. within 30 seconds. The polymerization activity decreased dramatically after 1.5 minutes. The reaction was terminated by adding 5 mL of MeOH after 10 minutes. The polymer was dried.
Yield=4.1 g. Activity=381.2 g PE/mmolcat*hr. Mw=600.1*10 3 . PD=1.86. Tm=134.3° C.
Comparative Example
The Iron Complex (VII) With MAO Activation
Toluene (216 mL) was transferred into the reactor. The solvent was heated to 140° C. and saturated with 286 psig of ethylene. PMAO-IP (3.83 mmol, 0.85 mL) was first injected into the reactor. After one minute, the catalyst (VII) (64.8 umol, 39.2 mg) dissolved in toluene (12.2 mL) was injected into the reactor. The polymerization happened immediately and reaction temperature increased to 162° C. within 30 seconds. The polymerization activity decreased dramatically after 3 minutes. The reaction was terminated by adding 5 mL of MeOH after 10 minutes. The polymer was dried.
Yield=10.3 g. Activity=960.0 g PE/mmolcat*hr. Mw=457.5*10 3 . PD=45.62. Tm=99-123° C. multi-peaks. | Olefin co- or homopolymers having a good molecular weight and short chain branching may be prepared in the presence of a tridentate complex of a Group 8, 9 or 10 metal. | 2 |
TECHNICAL FIELD
The invention relates to a vial docking station for simultaneously sliding the spouts of a plurality of liquid medicament vials into an engaged position with matching receptacles of a like plurality of liquid reconstitution diluent bags.
BACKGROUND OF THE ART
In hospital pharmacies, a common activity is to prepare several intravenous delivery bags with saline solutions for example to be mixed with various liquid medicaments to the specification of doctors. Often, the liquid medicines are provided in vials or glass bottles with a rubber sheet diaphragm across the spout of the bottle sealed with a metal rim and removable seal. The liquid medicines can be accessed by hypodermic needle for example, piercing through the rubber diaphragm and withdrawing liquid medicine into a hypodermic needle. Also commonly in hospitals, the vials are provided in measured doses by the drug manufacturer and the hospital pharmacy prepares intravenous solutions by engaging the spouts of the vials with matching receptacles on the sealed sterile diluent bags. The receptacles include sliding or telescoping means to engage a piercing needle on the receptacle and release the medicine from the vials into the saline solution in the diluent bag by permitting air to pass one way into the vial and thereby releasing the liquid through the needle.
Manually engaging the vials with receptacles of diluent bags involves many risks including physical injury or biological contamination from sharp needles, contamination of adjacent atmosphere with powerful or toxic medicines, and exposure of pharmacy workers to long term low concentrations of drugs. In order to address these risks, the prior art includes various mechanical devices to ensure safe engagement of vials with the receptacles and includes mechanical devices that can be positioned under exhaust hooks to avoid contamination.
U.S. Pat. No. 5,037,390 to Raines et al. shows a method of preparing diluent solution bags from a number of different vials of medicines of different sizes. The fluid medicament from the vials is conducted through a perforated needle in a one way valve into a manifold, which conducts the mixture of medicines to a diluent bag for delivery to the patient.
U.S. Pat. No. 6,070,761 to Bloom et al. shows a complex automatic system for mixing medicines for multiple vials that are delivered through needles into a plastic cassette with various channels and vials are mixing and delivering the medicament to an automatic delivery system.
Simple manual mechanisms for engaging a diluent bag with piercing needle and vials minimizing the risk of injury and exposure are shown in several patents such as U.S. Pat. No. 5,826,713 to Sunago et al., U.S. Pat. No. 5,478,337 to Okamoto et al. and U.S. Pat. No. 5,364,386 to Fukuoka et al. Apart from the examples mentioned above, it is considered well known to those in the relevant art that various devices are available for connecting vials containing medicaments with flexible diluent bags containing saline solutions.
A significant disadvantage of the prior art devices is the high cost and mechanical complexities. Due to these disadvantages, many hospital pharmacies rely on the physical labour of pharmacists to connect vials with receptacles individually. This method leads to fatigue and mistakes, personal injury and exposure to biological hazards as well as concentrated medicines which impose unacceptable risks to workers in hospital pharmacies as a result.
An unrecognised, but major cause of illness and some times death is human error in preparing medicines, which are delivered in the wrong concentration or to the wrong patient.
It is an object of the present invention to provide a simple low cost reliable tool for engaging vials of various sizes to diluent bags thus avoiding human contact and physical exertion as much as possible.
It is a further object of the invention to provide a mechanical system wherein vials of different sizes can be prepared in a ready position and double-checked before mixing for example with bar code readers in an optical checking system.
It is a further object of the invention to provide optional manually operated vial docking station and pneumatic or hydraulically operated version without significant modification to the mechanism.
Further advantages of the invention will be apparent from the following detailed description and accompanying drawings.
DISCLOSURE OF THE INVENTION
The invention provides a vial docking station for simultaneously sliding the spouts of a plurality of liquid medicament vials into an engaged position with matching receptacles of a like plurality of liquid reconstitution diluent bags. The vial docking station has a support frame that can be mounted to a wall or within an exhaust hood to reduce the risk of exposure.
The frame has a stationary bag mounting block with a series of spaced apart receptacle mounts. The mounts are C-shaped for suspending the diluent bags from their flexible inlet tube and receptacles below the mounting block. For different sizes or designs of receptacles, the mounts can include replaceable inserts or ferrules of different designs.
A header block is slidably mounted to the frame and has an equal number of plungers that are used to hold vials in an upturned position and to force the vial spout into sliding engagement with the receptacle. Each plunger is spring loaded or biased to firmly hold and guide the base of an associated vial in a ready position. In this position the vial is upturned to flow out under gravity when the seal diaphragm is pierced with the needle of the receptacle. The vial spout is aligned with the receptacle ready to be forced into sliding engagement with the plungers. Each plunger is manually individually operable between the ready position and a retracted position wherein the vial base is manually lifted against the force of gravity and spring load to be disengaged from the plunger.
Plunger clamps are disposed on the header block, for releasably clamping each plunger to move with the header block. A manually operated or mechanically operated actuation mechanism is mounted to the frame and engages the plunger clamps and the moveable header block for moving the header block progressively from the ready position forward to the engaged position, and rearward to a withdrawn position and for actuating the plunger clamps during movement between the ready position and the withdrawn position.
The plungers have a head with a conical self-centering vial base mating socket and a rod slidably mounted to the header block. The plunger head is spring loaded toward the bag mounting block to hold the vials ready in an upturned position above the bag receptacles.
The plunger clamp has a lock lever pivotally mounted to the header block for rotation about an axis transverse to the plunger rod. The rod extends through an aperture through the lock lever and the lock lever can move between a free sliding position and a clamped position wherein lock lever is disposed relative to the plunger rod with peripheral edges of the aperture gripping an outer surface of the rod. The offset aperture therefore binds or grips the cylindrical rod.
Further advantages of the invention will be apparent from the following detailed description and accompanying drawings.
DESCRIPTION OF THE DRAWINGS
In order that the invention may be readily understood, two embodiments of the invention are illustrated by way of example in the accompanying drawings.
FIG. 1 is a front elevation view of a manually operated embodiment of the invention showing a rectangular frame with bag mounting block suspending four diluent bags by their receptacles and including four vials in an inverted or upturned position aligned with the receptacles, the vials being of different sizes adapted with the spring loaded plungers.
FIG. 2 is a perspective view of the manual embodiment shown in FIG. 1 .
FIG. 3 is a detailed view of the manual embodiment with the crank shaft, cam shaft and lock levers positioned on the movable header block spring loaded upwardly from the stationary bag mounting block.
FIGS. 4, 5 , 6 , and 7 show the progressive downward motion of the crank arm of the manual embodiment which is manually rotated clockwise to simultaneously force the movable headed block downwardly and clamp the plungers to move with the header block by releasing the lock levers to bind with the cylindrical rods of the plunger.
FIGS. 8 and 9 show detailed view of the lock lever of the manual embodiment spring loaded to an upward position and pivoted to allow the plunger rod to slide freely (in FIG. 8) and to bind the slide rod (shown in FIG. 9 ).
FIG. 10 shows a pneumatically or hydraulically actuated embodiment of the invention (similar to the view of the manual embodiment of FIG. 2 but shown from the rear rather than front view) with a single central actuating cylinder engaging the movable header block
FIG. 11 shows a detailed view of the end cam followers engaging a pin mounted to the frame for rotating the cam shaft as the cam shaft and header beam move downwardly thereby releasing the spring loaded lock levers to bind on the rods of the plunger.
FIGS. 12, 13 , 14 and 15 show the progressive rotation of the cam shaft with cam follower engaging the pin projecting from the frame side wall and showing the releasing of the lock levers spring loaded to a position which binds at an angle to the rod of the plunger.
FIG. 16 and 17 show detailed sectional views of the cam shaft with cam lobe that engages and disengages the lock lever in FIG. 16 showing the lock lever disengaged from the plunger rod, whereas FIG. 17 shows the binding between the aperture in the lock lever and the cylindrical plunger rod.
Further details of the invention and its advantages will be apparent from the detailed description included below.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
With reference to FIGS. 1 and 2, the invention provides a manually operated vial docking station that accommodates vials 1 of different common sizes and simultaneously slides the spout of the inverted or upturned vials 1 into an engaged position with matching receptacles 2 of a spaced apart series of diluent bags 3 .
The vial docking station includes in the embodiment illustrated a rectangular frame 4 for hanging on a wall in a vertical position. It will be understood that different embodiments can be provided for table top use or in a is horizontal position with equal advantage. The frame 4 includes a horizontal bag mounting block 5 with a spaced apart series of receptacle mounts 6 . The embodiment illustrated shows the bag mounting block 5 fixed in position to side walls 7 . The stationary portions of the frame also include middle beam 8 and top beam 9 .
A slidable header block 10 is manually operated with crank arm 11 in a manner, which will be described in detail below. The header block 10 slides on vertical pins 12 and is spring loaded to an upward position against middle beam 8 with springs 13 .
The header block 10 also includes plungers 14 that are clamped and unclamped to move simultaneously up and down with the header block 10 thereby exerting force on the bottom of the vials 1 sufficient to slidably engage the spout of the vials in the receptacles 2 .
The plungers 14 include a head 15 and a rod 16 . The rods are guided but otherwise free to slide through middle beam 8 and slide through header block 10 when unclamped. Clamps on the header lock 10 that secure the rods 16 to the header block 10 are actuated by the manual motion of the crank arm 11 once the vials are manually placed in position shown in FIGS. 1 and 2. A spring 17 engaging a collar 18 on the slidable rods 16 together with the gravitational force of the weight of the plunger 14 hold the vials 1 in a ready position. The operator grasps the plunger head 15 and lifts upward to a withdrawn position against the force of the spring 17 to insert and remove the vials 1 . In the embodiment shown the plunger heads 15 have a conical self centering socket 19 for locating and holding the base of any size of vial 1 .
FIGS. 4, 5 , 6 , and 7 show the manual embodiment of the invention in a sectional view through middle beam 8 and movable header block 10 . The header block 10 is mounted to middle beam 8 of the frame on pins 12 with spring 13 to slide up and down during manual operation of the crank arm 11 in a clockwise direction progressing from FIG. 4 through FIG. 7 .
Rotation of the crank arm 11 rotates crank shaft 20 . and lever arm 21 , which engages cam follower 22 thereby rotating cam shaft 23 . Rotation of the cam shaft 23 with cam lobe 28 releases spring loaded lock lever 24 to the position shown in FIGS. 6 and 7 binding on the rod 16 extending through lock lever 24 . Further rotation of the lever arm 21 engages a top surface of the header block 10 pushing the plungers 14 downwardly to the engaged position as shown in FIG. 7 .
To recap therefore the header block 10 mounts to the frame with series of plungers 14 , each of which is biased to engage the base of an associated vial 1 in a ready position as shown in FIGS. 1 and 2.
Each plunger 14 is manually, individually operable between the ready position shown in FIG. 1 and a retracted position for disengaging the vial base from the plunger 14 .
The plunger clamping position is illustrated in FIGS. 8 and 9 in detail. Plunger rods 16 engage through the movable header block 10 and are spring loaded to a downward position with springs 17 . FIGS. 8 and 9 show the details of plungers clamps disposed. on the header block 10 to releasably clamp each plunger rod 16 and inhibit relative motion between the plunger 14 and the header block 10 . The manual actuation mechanism comprising crank arm 11 , crank shaft 20 and lever arm 21 as described above serve to engage the plunger clamps, the header block 10 or the bag mounting block 5 and move the header block 10 relative to the bag mounting block 5 from the ready position shown in FIG. 1 to the engaged position shown in FIG. 7 and rearwardly withdraw the header block 10 under the force of lift springs 13 automatically disengaging the plunger clamps.
As seen in FIGS. 8 and 9, the plunger clamps comprise a lock lever 24 , which is pivotally mounted on pin 25 to rotate about an axis transverse to the plunger rod 16 . The rod 16 extends through an aperture 26 extending through the lock lever 24 . The lock lever 24 moves between the free sliding position shown in FIG. 24 and clamped position shown in FIG. 9 . In the clamped position, the lock lever 24 is disposed relatively to the plunger rod 16 such as peripheral edges of the aperture 26 grip the outer cylindrical surface of the rod 16 . The lock lever 24 is spring loaded to the upward position of FIG. 9 by spring 27 . Since the aperture 26 in the sliding free position shown in FIG. 8 closely matches the outer cylindrical surface of the rod 16 , only a slight offset motion (as illustrated in FIG. 9) is required in order to tightly bind the rod 16 in the aperture 26 and prevent movement relative to the header block 10 . Rotation of the cam shaft 24 mounted to the header block 10 causes the cam lobe 28 to rotate (as shown between FIG. 8 and FIG. 9) in a counter clockwise motion thereby freeing the spring 27 to pivot the lock lever 24 about pin 25 .
As best seen in the progression shown in FIGS. 4, 5 , 6 , and 7 , the cam shaft 23 includes a cam follower 22 for rotating the cam shaft 23 as the header block 10 progresses between the ready position, a fully engaged position and a withdrawn position. In the withdrawn position, the vials 1 can be removed by raising the plunger 14 manually and lifting the empty vial from engagement with the receptacle 2 . At this point, the bag 3 with sealing solution and mixed medicament can be delivered to patient care providers.
As seen in the progression between FIGS. 4, 5 , 6 , and 7 , manual rotation of the crank shaft 20 with crank arm 11 rotates lever arm 21 , which serves two functions. Firstly, interaction with cam follower 22 and lever arm 21 serves to rotate cam shaft 23 thereby releasing cam lobe 28 from engagement with lock lever 24 . As shown in FIGS. 6 and 7, releasing lock lever 24 results in binding of the plunger rods 16 with the lock lever 24 as best seen in FIGS. 8 and 9. Further, manual rotation of the lever arm 21 as shown in FIGS. 6 and 7 pushes on the top surface of the header block 10 and brings the header block 10 with attached plungers downward against the force of spring 13 compressed between the header block 10 and stationary middle block 8 .
FIGS. 10 through 17 disclose a second embodiment of is the invention that is not manually operated but rather is operated primarily through use of a pneumatic or hydraulic cylinder 29 . As shown in FIG. 10, the cylinder actuates motion of the header block 10 sliding it vertically with respect to the stationary middle block 8 in a manner similar to that described above in respect of the manually operated embodiment.
In the mechanically operated embodiment, the mounting of the bags 3 in the bag mounting block 5 and the motion of the plungers 14 is identical to that described above. However, in the mechanically operated version there is no crank shaft 20 , lever arm 21 or crank arms 11 . The functions performed by these manually operated elements to rotate the cam shaft 23 and move the header block 10 are performed as follows.
FIGS. 12, 13 , 14 , and 15 show the progressive motion of the plunger 14 as the plunger rod 16 is clamped with lock lever 24 through the action of rotating cam shaft 23 thereby releasing engagement between the cam lobe 28 and lock lever 24 , in a manner similar to that described above. FIGS. 16 and 17 show means by which the rods 16 and lock levers 24 are engaged and disengaged under the action of spring 27 as the lock lever 24 rotates about pin 25 .
However, as seen in the detail of FIG. 11 as well as FIGS. 12 through 15, the rotation of the cam shaft 23 is performed in a different manner. The up and down motion of the header block 10 is controlled by the stroke of the cylinder 29 . Due to the possibility of physical injury to operators using an automated device, it is likely necessary to ensure that both of the operator's hands are out of the way of the plungers 14 and header block 10 before the cylinder 29 is activated. Therefore conventional twin push buttons are recommended for safety reasons.
The progression shown in FIGS. 12 through 15 and detail of the end view of the cam shaft 23 in FIG. 11 indicate that each of the frame side walls 7 include a pin 30 . In the mechanical operated embodiment, the cam follower 22 mounted to the cam shaft 23 is located at the two ends of the cam shaft 23 and has a different profile to interact with the pin 30 projecting from the frame side wall 7 . As shown in the progression through FIGS. 12, 13 , 14 and 15 , the interaction between the moving cam surface of cam follower 22 with the stationary pin 30 results in a simple mechanism which rotates the cam shaft 23 and thereby engages and disengages the cam lobe 28 from the top surface of each lock lever 24 .
As described above, the invention includes both a manually operated version in FIGS. 1-9 and a mechanically operated version in FIGS. 10-17, both of which utilize many common features such as plungers 14 , movable header block 10 and lock levers 24 . The invention overcomes the disadvantages of the prior art in enabling simple accommodation of various different sizes of vials simultaneously as shown in FIG. 1 with a simple mechanism that is inexpensive and easy to operate.
Although the above description relates to a specific preferred embodiment as presently contemplated by the inventor, it will be understood that the invention in its broad aspect includes mechanical and functional equivalents of the elements described herein. | A vial docking station for simultaneously sliding the spouts of a plurality of liquid medicament vials into an engaged position with matching receptacles of a like plurality of liquid reconstitution diluent bags. | 8 |
This is a continuation of application Ser. No. 477,085, filed Apr. 28, 1983, now abandoned, which is a continuation of Ser. No. 279,891, filed July 2, 1981, now abandoned which itself is a division of Ser. No. 104,496, filed Dec. 17, 1979, now abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to rocket and missile control systems and, more particularly, to a control system utilizing elastic deformation of portions of a rocket structure to control direction, rotation, speed, and other flight characteristics.
2. Description of the Prior Art
Many systems have been defined and described in the prior art to control and direct missile flight. U.S. Pat. Nos. 3,081,703 to Kamp et al and 3,710,715 to Hoofnagle disclose essentially skirt-like projections from the ends of projectiles to stabilize the projectile during flight. U.S. Pat. Nos. 3,785,567 to Fisher and 3,933,310 to Hickox disclose jet engine and rocket exhaust structures, respectively, which can be directed in order to control gas flow.
Another step taken to provide for the directing of exhaust gases in rockets and jet engines is the provision of flexible tubing as an integral part of the exit nozzle. The exit nozzle is then provided with means to position it, and thus direct exhaust gas flow. Such a system is disclosed, for example, in German Pat. No. 1,080,862 and in U.S. Pat. No. 3,759,447 to Weigmann.
Also, the art contains numerous references to the flexing of an actual nozzle structure in order to control the thrust direction; for example, see U.S. Pat. Nos. 2,546,293 to Berliner, 3,182,452 to Eldred, 3,258,915 to Goldberg, and 3,860,134 to Kobalter. These references utilize flexible sealing means, elastomeric materials and nozzle deformation to effect the directing of the exhaust gases. Further, the art often utilizes other controlling devices and assemblies, and other complex gas directing system. However, all of these systems are bulky, they require special sealing means, and, when dealing with rocket engines, they present the significance problem of the need of an elastomer to withstand the heat, pressure and abrasion which occurs during propulsion of the rocket.
The art has also suggested the use of control surfaces which are hinged on the surface of the projectile. The hinges are perpendicular to the longitudinal axis of the projectile, and the resulting control surfaces project outwardly from the relatively cylindrical surfaces of the projectile. Exemplary systems of this nature are found in U.S. Pat. Nos. 412,670 to Ross, 1,181,203 to Alard, and 3,007,411 to Piper et al. These systems are generally spring loaded, or otherwise hinged in some form so that after release and during flight, they provide a stabilizing effect on a projectile. However, such systems are designed for smaller projectiles and are normally not adjustable as they are merely for the purpose of controlling trajectory during the short term flight of such projectiles.
Foldable or bendable elastic control surfaces such as fins have been suggested for use by the prior art, particularly where space is at a premium. Exemplary systems include those disclosed in U.S. Pat. Nos. 3,114,287 to Swain, 3,165,281 to Gohlke, and 3,374,969 to Rhodes. These systems all suffer from the drawback of not being adjustable at deployment, and the possibility that the flexible or elastometric material will not totally straighten or properly position itself after firing. Thus, significant problems could arise relating to the effective deployment of the fins or control assemblies.
In summary, this prior art provides numerous methods, all of which suffer from some disability or another, such as sealing problems and lack of flexibility in the control of the various stabilizing devices. All of these conventional structures have been previously improved upon by applicant in his U.S. Pat. No. 4,044,970 which utilizes several reaction thrust motors on tail fins to rotate with the tail panels, and steer the rocket. Typical boost phase rocket structures provide very low tail panel effectiveness, while the present systems improve such tail panel effectiveness, as well as improving aerodynamic stability after, for example, booster burnout.
SUMMARY OF THE INVENTION
In brief, systems in accordance with the present invention provide for directional control of a rocket and control of the rocket's attitude while improving its aerodynamic stability. This is effected by providing a system with one or more components which achieve such improvements without requiring the inclusion of components in the system which would increase the weight and complexity of the system. As a result the present invention does not decrease payload capacity.
In order to perform these functions, the rockets of the present invention are provided with flexible, elastic structural members, and means for bending such elastic structural members to effect improved rocket flight stability and directional control. In a first form of the present invention, the rocket is provided with the flexible elastic and deformable member as the connection between the rocket body and the nozzle; and a plurality of separate nozzle rotating devices, such as hydraulic pistons, are provided. The hydraulic pistons are independently and continuously adjustable in response to control signals received from, for example, the missile's attitude sensor or ground control sources. The elastic flexible structure lessens the amount of direct contact between the high temperature exhaust gases, and the flexible portion of the design, and allows for a high degree of rotation and continuous angular adjustment based on the outside signals.
The rockets produced in accordance with the present invention may also be provided with the normal directional control and stabilizing fins utilized in rockets. In this added embodiment, the leading edge of at least some of such fins is fixed in place and the fins are manufactured of normal structural materials, but are sufficiently flexible over their length to allow for adjusting means to be provided at the rear end. The adjusting means is continuously adjustable, and may take the form of a screw with a threaded sleeve. Adjustment is in response to a signal from an external source and causes deflection in the control surface.
In the alternative, the skin of the rocket may be provided with longitudinal sections, each of which is independently deformable and actuable to produce a smooth, continuously increasing section as one approaches the rear of the rocket. This form may be utilized with or without the normal stabilizing side fins in the rocket design, and is most particularly useful where it is desired to slow a rocket down during flight by the production of an increase in drag.
In the first embodiment, the flexible surface is utilized for directional control, as it is in the second embodiment, but the second embodiment may also be quite useful to improve stability of the rocket after launch, as may the third embodiment. This is particularly true where the fins or sections are asymmetrically operated.
The provision of the deformable material in the design of the rocket structure advantageously improves the weight characteristics and thus increases payload potential of the rockets. This improvement is occasioned by the limination of independent hinges or bearing systems to adjust the sections used for rocket control, and the elimination of some duplicate components, such as the multi-layered flexible hose type of nozzle structure. These factors are combined with the improvement that the structures are controllable during flight. Further, the bending is specifically designed to stay within the elastic deformation limits of the material in use. Thus, a simpler, lighter weight, more effective rocket may be provided.
BRIEF DESCRIPTION OF THE DRAWINGS
A better understanding of the present invention may be had from a consideration of the following detailed description, taken in conjunction with the accompanying drawings in which:
FIG. 1 is a schematic diagram of a side section of a rocket showing the basic nozzle connection structures of the present invention;
FIG. 2 shows the rocket nozzle in deformation in accordance with one embodiment of the present system;
FIG. 3 shows a variation on the rocket nozzle designed in accordance with the present invention;
FIG. 4 is a cross sectional view taken along lines 4--4 of FIG. 3;
FIG. 5 is a side view showing certain external fin structure of the rocket of the present invention;
FIG. 6 shows one of the fins in full deformation;
FIG. 7 shows an end view of the structure in accordance with the arrangement of FIG. 5;
FIG. 8 shows the screw and threaded sleeve structure in full deformation as in FIG. 6;
FIG. 9 is a partial schematic showing flexible drag vanes prior to deployment;
FIG. 10 shows a side view of the rocket of FIG. 9 with the drag vanes fully deployed and operational;
FIG. 11 is an end view of the embodiment of FIG. 9 prior to deployment;
FIG. 12 is an end view of the fully deployed embodiment as shown in FIG. 10; and
FIG. 13 is a block diagram showing control circuitry utilizable in the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
In the embodiment shown in FIGS. 1 through 4, and more particularly in FIG. 1, the sectional schematic view of the rocket shows cylindrical body 10 having connected thereto rocket nozzle 12 and hydraulic cylinders 14 and 18 having piston rods 16 and 20, respectively, attached to the nozzle and effective to position the nozzle upon receipt of external signals, as shown in FIG. 13. In the embodiment shown in FIG. 1, deformable member 22 is provided between the nozzle and the main body of the rocket, and forms the seal which forces the gases produced during ignition out of nozzle 12. For straight line travel, such as during lift off, the nozzle's position is shown in FIG. 1 as having a relatively vertical center line 24 which is essentially coaxial with the center line of the rocket. Should there be a plurality of rocket nozzles, the center line of each nozzle would be parallel to the center line of the rocket.
In FIG. 2, the new center line resulting from the deformation in accordance with the present invention is shown by arrow 26. The deformation is effected by the extension of rod 20 from hydraulic cylinder 18, and the retraction of rod 16 by hydraulic cylinder 14.
As shown in FIG. 3, rocket body 10 is attached to elastically deformable member 27 which, in this embodiment, has a slightly wavy or curved shape, in section, in order to increase angular deformation before reaching the elastic limit of the material. The nozzle is, in this embodiment, movable by virtue of, for example, the same hydraulic cylinder/piston arrangement shown in FIGS. 1 and 2, but for the sake of clarity these have been omitted from this figure.
In FIG. 4, a section taken along lines 4--4 of FIG. 3 shows rocket body 10, nozzle 28, and the internal portion of the nozzle (shown as 30), as well as the cut-out of flexible elastic portion 32. This figure shows that the slight wave structure depicted in the side view of FIG. 3 is, in fact, circular in nature so that the nozzle may be rotated about a full 360 degree circle.
In FIG. 5, a second control structure is shown in partial schematic form. In this particular figure, the rocket 40 is provided with fins, generally shown as 42, for stabilization and directional control. Fins 42 are rigidly attached to the rocket body at 38, and adjustably attached to the rocket by way of screws 44 at the end of the rocket. Fin 46, as shown in FIG. 5, is also shown in FIG. 6 in its deformed state wherein screw 44 has been turned in such a manner that fin 46 is displaced to the end of the screw thread and yet is still rigidly attached to rocket body 40 at point 38.
In FIG. 7, an end view of the rocket shown in FIG. 5 is depicted showing fin 42 and 46 attached to screw members 44 and rocket body 40.
In FIG. 8, an enlarged schematic view of the preferred threaded member and screw adjusting arrangement for this portion of the present invention is shown. In this view, shaft 48 is screw-threaded, and has threaded onto it sleeve 50. Sleeve 50 is pivotally, if needed, attached to fin 52, and thus, when shaft 48 is rotated by external means, not shown, sleeve 50 traverses the length of shaft 48, and moves to deform fin 52 appropriately.
In this format, the portion of the present invention embodied by FIGS. 5 through 8 provides both stabilizing and directional control of the rocket, by the selective incremental adjustment of any or all of screw threaded members or screw threaded shafts in response to a ground control signal, an attitude sensor signal, or the like. Thus the direction and attitude of the rocket may be adjusted and changed, as desired.
In FIGS. 9-12, a third preferred control system of the present invention is shown. In this form, the surface of the rocket 60 is provided with a plurality of adjustable protrusions 62 (preferably four), each of which is an integral portion of the rocket body at its upper end, but, at its lower end (closest to the rocket nozzle) is provided with hydraulic cylinder 64 and its associated piston rod 66 which are independently actuable to elastically deform the skin of the rocket, at any selected time, in an outward manner in order to, for instance, increase drag and slow the rocket during flight. Note that a differential actuation, or actuation of only one member, will provide directional control of the rocket. In FIG. 9, the deformable portions are shown in their relaxed inward position, which is also indicated in FIG. 11 (an end view of FIG. 9) in partial schematic. In FIG. 10, each elastic section is deformed outwardly to the extent possible, which is limited by the elastic characteristics of the surface material. As shown in FIG. 12, this deformation results from hydraulic cylinder 64 being actuated to push rods 66 in an outward direction in order to deform surfaces 62. It should be noted at this point that different numbers of deformable members may be utilized, that they may be actuated by other means, and that they may be actuated both individually and jointly, but they should be independently actuable and, preferably, such actuation should be relievable during flight. The sections are, at least, adjustable as in the other embodiments disclosed herein, by virtue of signals received from attitude sensors or ground control signal sources.
In the block diagram of FIG. 13, signals from ground control station 70 and from attitude sensors 72 on the rocket are both provided to control circuitry 74, which communicates with, for instance, servomotors 76. Each servomotor may be interconnected with, for instance, shaft 44 in FIGS. 5, 6 and 7 or a fluid pump to the drive hydraulic cylinders shown in FIGS. 1, 2 and 10, 11 and 12. In this manner, the control circuitry would be actuated in accordance with rocket attitude and ground control signals to actuate the appropriate servos, and adjust the rocket nozzle position, the fin positions, or the drag sections. Thus, appropriate control of the attitude, direction of travel, and/or speed of the rocket, can be effected.
The materials utilized in construction of these elastic control surfaces, in accordance with the present invention, are the same materials ordinarily used on the surface of the rocket, and this is a distinct advantage of the present invention. That is, almost all metals are, at least to a certain extent, deformable, and therefore elastic, and thus the normal state-of-the-art rocket materials may be utilized to perform the functions of the present invention. The result of this advantage is the weight decrease noted above.
Although there have been described above specific arrangements of a control system for a rocket in accordance with the invention for the purpose of illustrating the manner in which the invention may be used to advantage, it will be appreciated that the invention is not limited thereto. For example, although the invention has been disclosed in the context of association with rockets, the principles of the invention are equally applicable to long range missiles or the like. Accordingly, any and all modifications, variations or equivalent arrangements which may occur to those skilled in the art should be considered to be within the scope of the invention as defined in the appended claims. | A missile is disclosed which utilizes elastic deformation of structural members in order to control missile flight. The elastic deformation may be in the mounting of the rocket nozzle, the provision of deformable control surfaces, or provision of deformable sections of rocket body, all of which are controlled by independent actuating means. | 5 |
TECHNICAL FIELD OF THE INVENTION
This invention relates to the fields of room partitioning components, and especially to interconnection systems and devices for moveable and reconfigurable partitioning panel systems.
CROSS-REFERENCE TO RELATED APPLICATIONS
Not applicable.
FEDERALLY SPONSORED RESEARCH AND DEVELOPMENT STATEMENT
This invention was not developed in conjunction with any Federally sponsored contract.
MICROFICHE APPENDIX
Not applicable.
INCORPORATION BY REFERENCE
Not Applicable.
BACKGROUND OF THE INVENTION
In modern office buildings, business and conference centers, hotels, classrooms, medical facilities, and the like, the fitting-out of occupiable space is continuously becoming more important and ever more challenging. In the competitive business environment, cost concerns alone dictate the efficient use of interior space. Thus, the finishing or fitting-out of building spaces for offices and other areas where work is conducted has become a very important aspect of effective space planning and layout.
Business organizations, their work patterns and the technology utilized therein are constantly evolving and changing. Building space users require products that provide for change at minimal cost. At the same time, their need for functional interior accommodations remains steadfast. Issues of privacy, functionality, aesthetics, acoustics, etc., are unwavering. For architects and designers, space planning for both the short and long term is a dynamic and increasingly challenging problem. Changing work processes and the technology required demand that designs and installation be able to support and anticipate change.
Space allocation and planning challenges are largely driven by the fact that modern office spaces are becoming increasingly more complicated due to changing and increasing needs of users for more and improved utilities support at each workstation or work setting. These utilities encompass all types of resources that may be used to support or service a worker, such as communications and data used with computers and other types of data processors, telecommunications, electronic displays, etc., electrical power, conditioned water, and physical accommodations, such as lighting, HVAC, sprinklers, security, sound masking, and the like. For example, modern offices for highly skilled “knowledge workers” such as engineers, accountants, stock brokers, computer programmers, etc., are typically provided with multiple pieces of very specialized computer and communications equipment that are capable of processing information from numerous local and remote data resources to assist in solving complex problems. Such equipment has very stringent power and signal requirements, and must quickly and efficiently interface with related equipment at both adjacent and remote locations. Work areas with readily controllable lighting, HVAC, sound masking, and other physical support systems, are also highly desirable to maximize worker creativity and productivity. Many other types of high technology equipment and facilities are also presently being developed which will need to be accommodated in the work places of the future. Moreover, the office space layout of these “knowledge workers” changes frequently to accommodate new technology, or to accommodate changing work teams resulting from changing business objectives, changing corporate cultures, or a combination thereof.
Office workers today need flexible alternative products that provide for the obtainment of numerous, often seemingly conflicting objectives. For example, the cultural aims of an organization may require the creation of both individual and collaborative spaces, while providing a “sense of place” for the users, and providing a competitive edge for the developer. Their needs include a range of privacy options, from fully enclosed offices which support individual creative work to open spaces for collaborative team work. At the same time, their products must be able to accommodate diverse organizations, unique layout designs, and dynamic work processes.
Further compounding the challenge are the overall objectives to promote productivity, minimize the expenses of absenteeism and workman's compensation, and reduce potential liability. Meeting these objectives often requires improved lighting, better air quality, life safety, and ergonomic task support.
As previously mentioned, for primarily cost reasons, The efficient use of building floor space is also an ever-growing concern, particularly as building costs continue to escalate. Thus, open office plans that reduce overall office costs are commonplace, and generally incorporate large, open floor spaces. These spaces are often equipped with modular furniture systems that are readily reconfigurable to accommodate the ever-changing needs of specific users, as well as the divergent requirements of different tenants.
An arrangement commonly used for open space office plans includes movable partial height partition panels that are detachably interconnected to partition off the open spaces into individual work settings and/or offices. These panels are typically configured to receive furniture units, such as work surfaces, overhead cabinets, shelves, etc., that hang from a framework. Another common arrangement involves dividing and/or partitioning open plans using of modular furniture, in which a plurality of differently shaped, complementary free-standing furniture units are positioned in a side-by-side relationship, with upstanding partial height privacy screens attached to selected furniture units to create individual, distinct work settings and/or offices. These types of modular furniture systems are considered readily reconfigurable and are easily moved to new sites, and are generally not part of a permanent leasehold improvement. Both of these arrangements typically incorporate panels that are largely hollow and usually comprised of a skeletal framework that support two face panels and some sort of edge plates on the top, bottom and sides.
Further, these arrangements most commonly include partial height partitions or dividers as opposed to full height walls spanning from ceiling to floor. No two office spaces are exactly alike. Floor to ceiling height, location of structural members, permanent walls, and utility and HVAC plenums vary from location to location. Thus, space-dividing systems must be adaptable to accommodate these variables. Furthermore, accommodating the varied requirements of office workers within a given facility may require a combination of fall and partial height dividers to provide a range of privacy levels corresponding to an individual user's job functions.
Historically, office walls or partitions are made by erecting a wood frame, lining each side with gypsum board (sheet rock) panels, then finishing the wall surfaces with a variety of textures and paint. These conventional walls have proven sturdy, provide adequate superior privacy and sound proofing, and provide a surface that easily accepts wall hangings such as pictures, paintings, plaques and the like. Furthermore, as is commonly known, conventional walls can easily be repainted, retextured, and, readily patched and repaired when damaged. However, conventional gypsum board partitions are typically custom built floor-to-ceiling installations, which do not adequately address many of the needs of the ever changing high-tech “knowledge worker.” The need for increased utilities and partial height partitions have both proven to be needs that conventional gypsum board partitions fail to adequately address.
Conversely, presently available full and partial height architectural walls or partitions that are readily reconfigurable, have very little in common with gypsum board walls. Typically, they are comprised of hollow panels built around a metal frame, and are manufactured with a fixed surface such as cloth or other textured material attached to the surface. Consequently, finished walls are generally lightweight and have a less sturdy feel than gypsum walls. Furthermore, finished walls have a surface finish that is not readily replaceable or changeable and does not provide for hanging pictures, paintings, plaques and the like on a comparable basis to gypsum walls. These characteristics provide for walls that fail to meet some of the needs of the ever changing office tenants discussed supra.
Partition systems do exist that are designed to incorporate substantially solid panels, and can conceivably be used with compressed straw panels, but these systems possess many shortfalls when compared to subject invention. Most notably is the Ortech partition system disclosed herein. It is designed only for floor to ceiling applications and does not provide for the vertical disposal of utility wiring between panels. Additionally, the Ortech system does not provide a frame that is substantially flush with each panel face thereby providing for a substantially flat wall with a plurality of vertical utility plenums therein.
Therefore, what is needed in the art is an interior space-dividing system that provides the flexibility and reconfigurability of currently available partition systems while also providing the sturdiness, sound proofing, ease of resurfacing, and compatibility with conventional wall hangings provided by conventional gypsum board walls. Further, the need exists for a system that provides the versatility of full height and partial height application wherein vertical and horizontal utility plenums are numerous and closely spaced. The invention disclosed herein meets these needs, provides a system that is made primarily of recycled materials, and represents a significant improvement over existing art.
SUMMARY OF THE INVENTION
The present invention relates to the finishing or fitting-out of various types of interior building space such as offices, hotels, conference centers, business centers, meeting rooms, medical facilities, classrooms, etc. Particularly, the present invention provides for the finishing out of open interior space using an integrated partition system suitable for finishing-out said open space in a customizable and subsequently reconfigurable manner. Said partition system further provides for the use of solid core prefabricated panels held within rails that provide for a perimeter framework for the solid core panels, with said rails providing a network of conduits suitable for holding utility wiring there through.
The present invention discloses a modular office partition system based upon solid core panels comprised of a matrix of compressed straw lined on all sides by paper or paperboard. The compressed straw is arranged in layers with the straw fibers substantially parallel in orientation extending transversely across the panel from side to side when the panel is in a normal in-use orientation. Subject solid core panels are typically rectangular in shape, and typically will be oriented such that the longer edges are substantially vertical and the shorter edges are substantially horizontal. In this orientation, said straw fibers will be assume a generally horizontal orientation. Said solid core panels are suitable for securely accepting nails, tacks, screws and other connecting means for attaching and/or hanging items from the panel surfaces. Further, surfaces of solid core panels are suitable for accepting surface texture, paint, wall paper, and other conventional wall coverings. Additionally, said solid core panels possess sound insulating properties (disclosed herein) superior to both conventional gypsum board walls and many currently available commercial interior partition systems. Solid core panels further provide fire resistant properties superior to materials used in many presently available interior partition systems. To enhance flexibility, solid core panels can be cut and formed in the field using conventional tools such as circular, saber or band saws, routers, planers, sanders and the like. Ideally, however, a given partition system will be designed so that field alteration of solid core panels is minimized. In a preferred embodiment, solid core panels such as those manufactured by Affordable Building Systems of Texas are utilized.
Though the partition system disclosed herein includes a number of individual components, the system is designed around a compressed straw core panel. Said straw core panel is composed of highly compressed straw, usually wheat, rice, oat, or other recovered agricultural straw. Typically, panels are made through a dry extrusion process wherein straw is compressed into a substantially flat continuous web, normally between 1″ is and 3″ thick and between 30″ and 65″ wide. The continuous web is lined on all sides by paper or paperboard. The continuous web is then cut into rectangular panels of various lengths.
These straw core panels possess many unique properties highly suitable for partition system applications. For example, finished panels can easily be textured, painted, retextured, repainted, or covered with a variety of wall covering materials such as wallpaper or fabric comparably to conventional gypsum board walls or partitions.
Like conventional gypsum board or wood-based walls or partitions, straw core panels are suitable for accepting nails, tacks, screws or the like for hanging pictures, plaques, etc. As indicated by nail pull values listed herein, straw core panels possess nail pull properties superior to conventional gypsum board walls. Additionally, straw core panels are typically thicker and stronger, thus providing nails, screws, or the like driven therein support more weight than if driven into gypsum board.
Importantly, what is lacking in the art is a system suitable for effectively utilizing these straw core panels in a versatile modular office partition type system that is easily reconfigurable. Though these straw core panels possess many characteristics arguably ideal for interior partitions, existing partition systems either do not provide for incorporation of said straw core panels, or are limited in their application.
The system disclosed herein provides for the assembly of modular solid core partition panels. Said partition panels may be comprised of either a single solid core panel, a plurality of solid core panels, or transparent panel or any combination thereof with panels situated in edge to edge planar relation and held within a perimeter frame. Said perimeter frame includes horizontal and vertical rail assemblies that securely engage said solid core or glass panel(s) along the entire perimeter of said partition panel. Horizontal and vertical rail assemblies are further designed to releasably engage a plurality of connectors that provide secure edge to edge attachment of finished partition panels. Connectors further provide for partition panels to be easily connected in a parallel (planar), or perpendicular relationship there between. Also included and disclosed herein are various foot, crown and cover pieces that provide hollow interior axial space along perimeter frames that provides a conduit for utility wiring. Thus, utility wiring can be routed around the perimeter of finished partition panels. Further, rail assemblies, connectors, and associated pieces are designed to provide a continuous conduit through joint areas where partition panels edges are joined.
Size of finished partition panels can easily be varied to provide partial height or full height (floor to ceiling) partitions. Finished partition panel size can be changed either by the number of solid core panels included or by changing the length of the solid core panels. Partition panels can be erected as dividers or walls within open office space, or can be installed to cover permanent interior or structural walls to provide a consistent look and design throughout the entire interior space to be finished.
The present invention further provides for core panels that can be specially sized, either at the manufacturing plant or in the field, to provide doors, odd sized panels, transitional areas, etc., that are aesthetically and structurally consistent with partition is panels and provide a uniform “finished” look upon completion.
The features and advantages of the invention will be further understood and appreciated by those skilled in the art by reference to the following written specification, claims, and appended drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
The figures presented herein when taken in conjunction with the written disclosure form a complete description of the invention.
FIGS. 1 a through 1 f show individual sectional views of partition systems components; floor rail, ceiling crown, profile rail, and double ‘T’ connector, single ‘T’ connector, and crown rail respectively.
FIGS. 2 a through 2 e show individual sectional views of partition system components; window stop, covered window stop, vertical door rail, horizontal door rail, and base leg assembly respectively.
FIGS. 3 a through 3 d show individual sectional views of partition system components; outside corner cover, inside corner cover, base plate, and joint cover plate respectively.
FIGS. 4 a through 4 c provide a cross sectional detailed views of the standard clip connector and standard clip receiver, and the sub-components therein.
FIG. 5 shows vertical sectional view of a floor to ceiling multi-panel partition that includes compressed straw core panels.
FIGS. 6 a and 6 b show an end view of a vertical floor to ceiling partition and a vertical sectional end view of a vertical partition, with both views including compressed straw core panels.
FIGS. 7 a through 7 c show vertical sectional views of three alternative configurations of vertical floor to ceiling partitions.
FIGS. 8 a and 8 b show vertical sectional views of two alternative configurations of vertical partitions both including door members.
FIGS. 9 a and 9 b show a horizontal sectional views of a corner ‘L’ connection and a ‘T’ intersection both including straw core panels.
FIGS. 10 a through 10 c show horizontal sectional views of vertical partition connections including two straw core panels, two transparent panels, and two straw core panels with a door member in between.
DETAILED DESCRIPTION OF THE INVENTION
The detailed description will begin with a figure by figure view of the individual components and sub-components of subject partition system. This process will familiarize the reader with each individual component prior to viewing various interaction and interconnection therebetween.
FIGS. 1 through 4 inclusive, are all cross sectional views of individual components that typically take a linear form perpendicular to the cross section illustrated. Further, the length of each component can vary as needed. In a preferred embodiment of subject invention, the individual components detailed in FIGS. 1 through 4 are made of extruded aluminum, aluminum alloy, or other extrudable material of sufficient strength and stiffness.
Referring first to FIG. 1 c , an individual cross section view of a standard profile rail ( 3 ) is shown. As illustrated, profile rail ( 3 ) has a general ‘C’ channel cross sectional shape with two parallel shallow channels ( 29 ) on one side, and a larger open channel ( 28 ) opposite. On the inside of said open channel, opposite the opening are three substantially cylindrical openings. The two lateral openings are cap screw receivers ( 61 ), and the center cylindrical opening is a base leg receiver ( 62 ). The sides of profile rail ( 3 ) are defined by two side rails ( 39 ), with each side rail having an inwardly protruding retention rail ( 59 ) attached thereto. In this view, the top to bottom depth of open channel ( 28 ) is defined by retention rails ( 59 ) and cap screw receivers ( 61 ), and the inside width of open channel ( 28 ) is defined by side rails ( 39 ). As will be seen later in this disclosure, the inside dimensions of open channel ( 28 ) are sized to receive other components slidably therein.
Referring now to FIG. 1 a , an individual cross section view of a floor rail ( 6 ) is shown. Each floor rail ( 6 ) comprising two foot pieces ( 33 ), two mounting rails ( 34 ) and a single internal frame ( 40 ) there between.
FIG. 1 b shows and individual cross section view of a ceiling crown ( 4 ) comprised of a crown top ( 37 ) and two crown walls ( 38 ) collectively defining internal crown channel ( 36 ). Above crown top ( 37 ) are situated two contact rails ( 69 ) each situated to provide a contact with a ceiling located above.
FIGS. 1 d & 1 e show individual cross section views of double ‘T’ connector ( 15 ) and single ‘T’ connector ( 18 ). Each connector includes a cylindrical connector pin receiver ( 27 ), connector spines ( 30 ), and connector insert bars ( 31 ). Said insert bars ( 31 ) are sized to slidably fit within the open channels ( 28 ) of profile rails ( 3 ) discussed supra. Each single ‘T’ connector ( 18 ) includes a retention finger ( 68 ) designed to engage outside corner cover ( 19 ) detailed below.
Finally, FIG. 1 f shows an individual cross section of crown rail ( 22 ). Crown rail ( 22 ) provides an alternative for ceiling crown ( 4 ) in applications where a partial height partition in preferred and also includes crown walls ( 38 ) and crown top ( 37 ).
Several of the components included herein are designed to fixably attach to profile rail ( 3 ). These components are shown in FIGS. 2 ( a-d ). Referring first to FIG. 2 a , a cross section view of a window stop ( 7 ) is shown. Each window stop ( 7 ) includes a substantially rectangular channel member ( 48 ) and a standard clip connector ( 50 ). Further, FIG. 2 b shows a cross section view of a covered window stop ( 8 ). Each covered window stop ( 8 ) includes a substantially rectangular channel member ( 48 ), and standard clip connector ( 50 ) and a cover member ( 49 ). Continuing, FIG. 2 c shows a cross section view of horizontal door rail ( 16 ) including full face plate ( 56 ), door stop member ( 57 ) and two standard clip connectors ( 50 ). FIG. 2 d shows a cross section view of vertical door rail ( 9 ) including half face plate ( 58 ), door stop member ( 57 ), cover member ( 49 ), and standard clip connector ( 50 ).
Referring now to FIG. 2 e which shows a cross sectional view of base leg ( 11 ). Each base leg member includes threaded shaft ( 65 ), adjustment nut ( 72 ) and foot piece ( 73 ). Threaded shaft ( 65 ) being designed to fit firmly into base leg receiver ( 62 ) of profile rail ( 3 ), and adjustment nut ( 72 ) designed to rest on internal frame member ( 40 ) of floor rail ( 6 ).
To illustrate the designed interconnection between components in the preferred embodiment, FIGS. 4 ( a-c ) provides detailed views of standard clip connector ( 50 ) and standard clip receiver ( 46 ). As shown in FIG. 4 a , the sub-components of standard clip connector ( 50 ) include two substantially parallel insert legs ( 51 ), each with a retention tooth ( 52 ) at the end facing outward. Individual components are design to allow insert legs ( 51 ) to elastically bend slightly inward. FIG. 4 b , further shows the sub-components of standard clip receiver ( 46 ) that include a short retention foot ( 53 ), an opposed long retention foot ( 54 ) and two internal spaces ( 55 ) located adjacent to each. The distance between the end of short retention foot ( 53 ) and long retention foot ( 54 ) is designed to allow insertion of parallel insert legs ( 51 ) there between.
Continuing, FIG. 4 c shows individual sectional views of components, window stop ( 7 ), covered window stop ( 8 ) and profile rail ( 3 ) with standard clip connectors ( 50 ) and standard clip receivers ( 46 ) properly joined. Insertion of opposed insert legs ( 51 ) through the gap between short retention foot ( 53 ) and long retention foot ( 54 ) requires the slight elastic displacement of both insert legs ( 51 ) inward. Upon complete insertion, insert legs ( 51 ) return to original position pushing each retention tooth ( 52 ) into respective spaces ( 55 ), thus locking components into position. With the exception of the compressed straw panels, all components disclosed herein are preferably made from extruded aluminum or aluminum alloy. These materials provide for individual components that possess sufficient elasticity to be interlocked as described above.
Referring now to FIG. 3, wherein FIG. 3 a shows a cross section view of an outside corner cover ( 19 ), with two cover plates ( 42 ) arranged in substantially perpendicular respective orientation and defining a right angle. Each corner plate ( 42 ) includes an opposed pair of retainer clips ( 35 ) directed inward substantially 45 degrees to said corner plates ( 42 ). Said retainer clips ( 35 ) are designed to engage a retention finger ( 68 ) on single ‘T’ connector ( 18 ).
Progressing on to FIG. 3 b which shows a section view of an inside corner cover ( 14 ) that also includes two cover plates ( 41 ) arranged in substantially perpendicular respective orientation and also defining a right angle. Inside corner cover ( 14 ) includes a retainer insert ( 71 ), said retainer insert protruding outward along a line bisecting the angle formed by corner plates ( 41 ). Said insert ( 71 ) designed to fit between profile rails ( 3 ) of adjacent panel assemblies placed in substantially perpendicular orientation.
FIG. 3 c shows a cross section view of base plate ( 5 ) that includes coping plate member ( 43 ), retention rail ( 44 ) attached to said coping plate member ( 43 ) on one end and arranged substantially parallel thereto, thus defining an insert space ( 45 ) therebetween.
Further, FIG. 3 d shows a cross section view of joint cover plate ( 13 ) including a substantially flat face plate member ( 47 ), said face plate member ( 47 ) have two inserts ( 60 ) attached substantially perpendicular thereto at points approximately equidistant between face plate member ends and centers. Said inserts ( 60 ) each including a retainer ( 66 ) on the end opposite face plate member ( 47 ).
One of many advantages of the subject invention is a standard attachment means for attaching many of the peripheral components to the profile rail ( 3 ). Said standard attachment means, comprised primarily of standard clip connector ( 50 ) and standard clip receiver ( 46 ) described supra, provides for design simplicity allowing a minimal number of individual components. Limited components provides for a system that is cost effective to manufacture and relatively easy to learn and install.
Though the partition system disclosed herein includes a number of individual components, the system is designed around a compressed straw core panel ( 1 ). Said straw core panel is composed of highly compressed straw, usually wheat, rice, oat, or other recovered agricultural straw. Typically, panels are made through a dry extrusion process wherein straw is compressed into a substantially flat continuous web, normally between 1″ and 3″ thick and between 30″ and 65″ wide. The continuous web is lined on all sides by paper or paperboard. The continuous web is then cut into rectangular panels of various lengths.
These straw core panels possess many unique properties highly suitable for partition system applications. For example, finished panels can easily be textured, painted, retextured, repainted, or covered with a variety of wall covering materials such as wallpaper or fabric comparably to conventional gypsum board walls or partitions.
Like conventional gypsum board or wood-based walls or partitions, straw core panels are suitable for accepting nails, tacks, screws or the like for hanging pictures, plaques, etc. Importantly, the preferred straw core panels possess nail pull properties superior to conventional gypsum board walls, thus providing a superior mounting surface. Additionally, straw core panels are typically thicker and stronger, thus providing nails, screws, or the like driven therein support more weight than if driven into conventional gypsum board.
In the preferred embodiment, compressed straw panels manufactured by Affordable Business Systems (ABS) of Whitewright, Tex. are used. The ABS panels posses favorable structural and acoustic properties that provide a superior embodiment of subject invention. For example, these panels possess a structural rack load strength of 710 lbs., and a structural transverse load rating exceeding 105 lbs. according to ASTM E72-98. The ABS panels further provide a sound transmission coefficient (STC) of 29 according to ASTM E90-99, and a noise reduction coefficient (NRC) of 0.50 according to ASTM C423-00. The ABS panel also provide thermal insulating properties with an 1.481 R value according to ASTM C518-98. Importantly, the ABS panel has a nail pull rating of 97.8 lbs. according to ASTM C473-00. Additionally, the ABS straw core panels are highly fire resistant as indicated by the a Class A flame spread rating according to ASTM E-84-00a.
It should also be noted that the preferred embodiment disclosed herein includes glass panels ( 2 ), but alternate embodiments may include plexiglass, plastic, opaque materials or any other substantially solid material possessing proper dimensions to fit the components and sub-components disclosed herein. Substantially transparent panels, non-transparent panels, or panels with varying degrees of opacity may be utilized.
Referring now to FIG. 5 that shows a typical configuration of a panel in a floor to ceiling application. FIG. 5 is a vertical cutaway view showing two straw core panels ( 1 ) in typical side by side, substantially planar orientation. Each panel is bordered on all is four edges by profile rail ( 3 ). It is implied in FIG. 5 that each floor rail ( 6 ) rests on the floor and ceiling crown ( 4 ) is in flush contact with the ceiling. Alternatively, a crown rail ( 22 ) may be substituted for ceiling crown ( 4 ) for a partial height application. Importantly, when attached to either the top or bottom edge of straw core panel ( 1 ), profile rail ( 3 ) should be situated with the open channel ( 28 ) facing the panel to allow interface between standard clip receivers ( 46 ) and various components that include a standard clip connector ( 50 ). Similarly, when attached to the side of straw core panel ( 1 ), profile rail ( 3 ) should be situated with the open channel facing away from the panel to allow interface between the open channel ( 28 ) and components such as ‘T’ connectors ( 15 & 18 ).
In the preferred embodiment, top profile rails ( 3 ) are attached to straw core panels ( 1 ) by means of long lag screws ( 64 ). It is recommended that long lag screws be spaced no more that 16″ apart. In a preferred embodiment, ¼″×3″ lag screws are used. Prior to insertion, properly placed and sized holes are drilled through each profile rail ( 3 ).
Similarly, side profile rails ( 3 ) are attached to straw core panels ( 1 ) by means of short lag screws ( 63 ). It is recommended that short lag screws be spaced no more than 20″ apart. In a preferred embodiment, ¼″×2½″ lag screws are used. Prior to insertion, properly placed and sized holes are drilled through profile rail ( 3 ).
In alternative embodiments, profile rails ( 3 ) may be attached to edges of straw core panels ( 1 ) by means of nails, anchors, adhesives or other means. The most important objective is a rigid attachment between profile rails ( 3 ) and the edge of the panel held therein.
Referring now to FIG. 6 a , it is shown that profile rail ( 3 ) is attached at the bottom to base leg assembly ( 11 ). Each base leg ( 11 ) is comprised of a threaded shaft ( 65 ), foot piece ( 73 ) and adjustment nut ( 72 ). Threaded shaft ( 65 ) is movably disposed within base leg receiver ( 62 ). Base leg receiver ( 62 ) being an integral part of profile rail ( 3 ). The distance between profile rail ( 3 ) and foot piece ( 69 ) can be changed by rotating threaded shaft ( 68 ) and effectively screwing the shaft into or out of base leg receiver ( 62 ). Further, finer height adjustments can be made by rotating adjustment nut ( 72 ) and allowing foot piece ( 73 ) to drop with respect to floor rail ( 6 ). It can be seen that limited travel is available between foot piece ( 73 ) and floor rail ( 6 ), thus gross adjustment are made at the threaded shaft ( 65 ) base leg receiver ( 62 ) connection.
With continuing reference to FIG. 6 a , it can be further seen that both the top and bottom of side profile rail ( 3 ) includes a pair of cap screws ( 67 ). Each cap screw is placed through a concentric hole in side profile rail ( 3 ) and is fixably disposed within a concentrically situated cap screw receivers ( 61 ) on top and bottom profile rails. Said cap screw receivers ( 61 ) are shown in FIG. 6 b . Importantly. The cap screw connections at each corner effectively provide for a rigid profile rail frame around the straw core panel enclosed therein.
Referring back to FIG. 5, it can be seen the lower end of each base leg assembly ( 65 ) is attached to a floor rail ( 6 ). Each floor rail ( 6 ) is situated to lie flat on the floor below. As can be seen in FIG. 6 a , the base leg assembly ( 65 ) is attached to floor rail ( 6 ) by means of a rigid connection between internal frame ( 40 ) and foot piece ( 69 ).
Referring back to FIGS. 6 a and 6 b , the panel assemblies are covered by ceiling crown ( 4 ). In a floor to ceiling partition application, the ceiling crown contact rails ( 69 ) will come into flush contact with an interior ceiling. Alternatively, in partial height partition applications, crown rail ( 22 ) will provide a finished covering for the top edge of a panel assembly. The width of both crown rail ( 4 ) and ceiling crown ( 22 ) is sized to fit over the top edge of a panel assembly such that the lower ends of crown walls ( 38 ) continuously push inward against the panel assembly thus providing a snug, secure fit and preclude unwanted displacement. Importantly, properly positioned ceiling crown ( 4 ) or crown rail ( 22 ) provides a horizontal conduit space ( 74 ) running the length of a panel assembly. Said horizontal conduit space ( 74 ) provides a convenient enclosure for utility wiring. Conduit space located effectively within a crown piece can be accessed by simply sliding an individual crown piece upward and removing it from the panel assembly.
FIGS. 6 a and 6 b also show a horizontal conduit space ( 74 ) at the base of the panel assembly as defined by bottom profile rail ( 3 ), base plates ( 5 ) and floor rail ( 6 ). Importantly, bottom conduit space ( 74 ) runs the length of an entire finished panel assembly and also provides a convenient enclosure for utility wiring. Further, each base plate ( 5 ) is mounted to a mounting rail ( 34 ) located on floor rail ( 6 ). Each mounting rail ( 34 ) fits snugly into insert space ( 45 ) of base plate ( 5 ), securely holding said base plate ( 5 ) in a substantially vertical direction and causing the top edge of coping plate member ( 43 ) to push against the panel assembly, thus providing a tight fit. Bottom conduit space ( 74 ) can be accessed by sliding base plate ( 5 ) upward until mounting rail ( 34 ) is no longer held within insert space ( 45 ), then removing the individual base plate ( 5 ). Each base plate ( 5 ) is replaced by simply reversing the process above.
The vertical cutaway view of FIG. 5 also shows double ‘T’ connectors ( 15 ) holding parallel side profile rails ( 3 ) together. For better illustration, refer to FIG. 10 c that shows a horizontal cutaway view of a typical panel/panel joint. As illustrated, double ‘T’ connector ( 15 ) is positioned between two side profile rails ( 3 ) and an insert bar ( 31 ) is slidably disposed within the open channel ( 28 ) of each profile rail ( 3 ). Further, the overall length of double ‘T’ connector ( 15 ) provides the proper spacing between opposed retention rail members ( 59 ) to allow insertion of insert members ( 60 ) of joint cover plate ( 13 ) therebetween. Once inserted, joint cover plate ( 13 ) is snugly held in place by retainer ends ( 66 ) situated just past the ends of retention rail members ( 59 ). Although held tightly in place, joint cover plate ( 13 ) can be removed and replaced by hand. As also illustrated in FIG. 10 c , a vertical conduit space ( 75 ) is defined by profile rails ( 3 ) and joint cover plates ( 13 ). Vertical conduit space ( 75 ) provides a convenient vertical enclosure for utility wiring and the like.
An alternative partition configuration is shown in FIG. 7 a . In the vertical section view, it can be seen that the partition depicted includes a bottom straw core panel ( 1 ) and a top glass panel ( 2 ). As shown, the base of glass panel ( 2 ) rests within ‘U’ channel ( 32 ). In a preferred embodiment, ‘U’ channel ( 32 ) is made of a resilient material such as rubber or silicone. The base of ‘U’ channel ( 32 ) rests upon profile rail ( 3 ). ‘U’ channel ( 32 ) is bordered on each side by a covered window stop ( 8 ). Each covered window stop ( 8 ) is fixably attached to profile rail ( 3 ) by means of clip connector assembly ( 50 ) and clip receiver assembly ( 46 ) discussed supra. Likewise, the top of glass panel ( 2 ) is held within ‘U’ channel ( 32 ) which is securely held on each side by a window stop ( 7 ). Each window stop ( 7 ) is attached to profile rail ( 3 ) by means of clip connector assembly ( 50 ) located thereon and a clip receiver assembly ( 46 ) located on the profile rail ( 3 ) situated above. The entire partition is topped by ceiling crown ( 4 ) that rests against a ceiling above. In the configuration depicted in FIG. 7 a , the bottom of each crown wall ( 38 ) push against the bottom of profile rail ( 3 ) to provide a secure fit thereto. As can be seen, all configurations shown in FIG. 7 provide both a top and bottom horizontal conduit space ( 74 ).
An alternative partition configuration that does not include a straw core panel is shown in FIG. 7 b . Glass panel ( 2 ) spans the entire vertical distance between bottom profile rail ( 3 ) and the top profile rail ( 3 ). In this configuration, window stops ( 7 ) are used to enclose the ‘U’ channel ( 32 ) at both the top and bottom of glass panel ( 2 ). Importantly, in this configuration, the distance between floor rail ( 6 ) and bottom profile rail ( 3 ) is fixed such that the top ends of coping plates ( 5 ) are aligned with the join line between bottom profile rail ( 3 ) and window stops ( 7 ). The required distance can be “dialed in” by rotating the threaded shaft ( 38 ) of base leg ( 65 ) (not shown).
A third alternative partition configuration is shown in FIG. 7 c , wherein a glass panel ( 2 ) is situated between straw core panels ( 1 ) on both the top and bottom sides. As illustrated, straw core panels are held between profile rails ( 3 ) positioned with profile rail channels ( 28 ) facing the straw core panels ( 1 ). Glass panel ( 2 ) is held between profile rails ( 3 ) with profile rail channels ( 28 ) facing away. Glass panel ( 2 ) is enclosed on the top and bottom sides by ‘U’ channels ( 32 ) with each ‘U’ channel ( 32 ) held between covered window stops ( 8 ). As before covered window stops ( 8 ) and profile rails ( 3 ) are connected by means of clip connector assemblies ( 50 ) and clip receiver assemblies ( 46 ). Another advantage to the partition system disclosed herein is the inclusion of doors as an integral part of the overall system. In the preferred embodiment, doors are made from properly sized compressed straw core panels.
Referring now to FIG. 8 a , a vertical section view of a partition that includes a door is shown. Door panel ( 20 ) is generally situated below a straw core panel ( 1 ). At the base of straw core panel ( 1 ) is profile rail ( 3 ) with profile rail channel ( 28 ) facing straw core panel ( 1 ). Attached to the bottom of bottom profile rail ( 3 ) are covered window stop ( 8 ) and horizontal door rail ( 9 ). Both covered window stop ( 8 ) and horizontal door rail are attached to profile rail ( 3 ) by means of clip connector ( 50 ) and clip receiver ( 46 ).
For clarification, a horizontal section view of the same door detailed in FIG. 8 a is shown in FIG. 10 a . Door panel ( 20 ) is situated between straw core panels ( 1 ) located on each lateral side. Each vertical side edge of door panel ( 20 ) is adjacent a vertical door rail ( 16 ) with each attached to a vertical profile rail situated alongside. Each vertical door rail ( 16 ) is attached to a profile rail ( 3 ) by means of a pair of clip connectors ( 50 ) and clip receivers ( 46 ) as shown. Each profile rail ( 3 ) attached to a vertical door rail ( 16 ) is slidably attached, opposite vertical door rail ( 16 ), to a plurality of double ‘T’ connectors ( 15 ). As previously described, a slidable connection between profile rail ( 3 ) and double ‘T’ connector ( 15 ) is accomplished as insert bar member ( 31 ) is held within profile rail channel ( 28 ) by means of retention rail members ( 59 ). Continuing, each double ‘T’ connector ( 15 ) is then attached to a laterally positioned vertical profile rail ( 3 ) that is subsequently attached to a laterally positioned straw core panel ( 1 ). The vertical conduits ( 72 ) about double ‘T’ connectors ( 15 ) are covered on remaining open sides by joint cover plates ( 13 ). In the closed position, door panel ( 73 ) may lightly contact door stop members ( 57 ) along each vertical edge. A plurality of conventional door hinges can be attached on either side, such that the door panel ( 73 ) opens away from door stop members ( 57 ). Though shown on several drawings disclosed herein, door hardware, ie., knobs, locks, jambs, hinges, etc., can be conventional hardware and is not specific to this disclosure.
Referring now to FIGS. 9 ( a & b ) that shows horizontal section views of panel to panel connections. Referring first to FIG. 9 a , a two panel corner connection is shown. As seen, the vertical profile rails ( 3 ) facing the corner connection are each slidably attached to single ‘T’ connectors ( 18 ). Each insert bar member ( 31 ) is held within profile rail channel ( 28 ) by means of retention rail members ( 59 ) to provide a slidable attachment. Single ‘T’ connectors are then in perpendicular relative positions allowing the concentric alignment of pin receivers ( 27 ) and insertion of a connector pin ( 21 ) (not shown) there through. When straw core panels ( 1 ) and profile rails ( 3 ) are set in a substantially perpendicular relative position, a narrow gap between the inside corners of profile rails ( 3 ) will be present. This gap is suitable for accepting the retainer insert ( 71 ) of inside corner cover ( 14 ). Further, outside corner cover ( 19 ) can be placed over the outside corner of the connection as shown and held in place by the interaction between retainer clips ( 35 ) and retention finger ( 68 ) previously discussed. Though not illustrated, the top of the corner connection illustrated should be covered by two ceiling crown pieces ( 4 ) or crown rails ( 22 ) (neither is shown), and each should be mitered at substantially 45° angles and placed over each panel per previous discussion.
FIG. 9 b shows a horizontal section view of a typical three panel connection with two panels in substantially planar alignment and a third panel in substantially perpendicular position thereto. Each straw core panel ( 1 ) is attached to a profile rail ( 3 ) with profile rail channel ( 28 ) facing toward the joint area. The straw core panels ( 1 ) and respective profile rails ( 3 ) in planar alignment are each attached to opposite ends of a double ‘T’ connector ( 15 ) with insert bar member ( 31 ) slidably disposed within each profile rail channel ( 28 ). The straw core panel ( 1 ) and respective profile rail ( 3 ) in perpendicular alignment is attached to a single ‘T’ connector ( 18 ) with insert bar member ( 31 ) slidably disposed within profile rail channel ( 28 ). As illustrated, when the third panel is placed in substantially perpendicular alignment to the planar panels, the pin receivers ( 27 ) on double ‘T’ connector ( 15 ) and single ‘T’ connector ( 18 ) can be moved into concentric alignment to accept a connector pin ( 21 ) (not shown). Further, inside corner covers ( 14 ) should be placed over both inside corners with retainer insert members ( 71 ) positioned between profile rails ( 3 ). Joint cover plate ( 13 ) should be placed over the joint area opposite the perpendicular panel. Joint cover plate will be held in place by interaction between profile rails ( 3 ), insert ( 60 ) and retainer ( 66 ) as shown.
Importantly, each connection provides a vertical conduit space ( 75 ) for routing utility wiring and the like.
For a final overview, FIG. 11 contains an exploded view of a portion of a typical assembly. As can be seen, the assembly includes two fall size straw core panels ( 1 ) and one partial sized straw core panel located below glass panel ( 2 ). Additionally, a door panel ( 20 ) is shown. Miscellaneous system components as previously detailed herein are also shown. Of note, FIG. 11 shows optional insulating strips ( 76 ) that can be placed within horizontal conduit space ( 74 ) or vertical conduit space ( 75 ) as needed for added acoustical and/or thermal insulation.
Those skilled in the art will recognize that certain variations or alternative embodiments are easily accomplished with the invention disclosed herein. For example, the system of individual components can easily be used with core panels made from alternative materials such as solid wood, laminated plywood, particle board, oriented strand board, or various composite materials including but not limited to fiberglass, plastics, plexiglass, ceramics, masonry, or combinations thereof. Further, alternative materials may well be used in the various component parts without deviating from the invention claimed herein.
The embodiments shown and described above are exemplary. Many details are often found in the art and, therefore, many such details are neither shown nor described. It is not claimed that all of the details, parts, elements, or steps described and shown were invented herein. Even though numerous characteristics and advantages of the present inventions have been described in the drawings and accompanying text, the description is illustrative only, and changes may be made in the detail, especially in matters of shape, size, and arrangement of the parts within the principles of the inventions to the full extent indicated by the broad meaning of the terms of the attached claims.
The restrictive description and drawings of the specific examples herein do not point out what an infringement of this patent would be, but are to provide at least one explanation of how to use and make the inventions. The limits of the inventions and the bounds of the patent protection are measured by and defined in the following claims. | A reconfigurable office partition system that includes movable rigid panels each comprised of a core panel mounted within a perimeter frame. Said core panel comprised of a matrix of compressed straw or other cellulose-based natural fiber lined by paper or paperboard suitable for accepting a variety of surface treatments, and also suitable for accepting nails, screws or other means for hanging or otherwise attaching articles thereon. Frames comprised of vertical and horizontal rails specially adapted to engage said core panels and further adapted to releasably and slidably attach to a series of specialty connectors. | 4 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a safety gate for use in obstructing doorways, passageways and similar openings to restrict the movement of small children and the like.
2. Description of Related Art
A variety of gates are known and presently on the market that are designed to prevent children from passing from one area to another or from ascending or descending stairways. Several of these gates can be adjusted for use in openings having various widths. Several of these gates also include moveable bumpers that can be extended from and retracted into the gate to respectively secure and release the gate from the opening.
A disadvantage of known gates that utilize moveable bumpers is that the mechanisms used to actuate the bumpers are complex and expensive. These gates conventionally incorporate mechanisms that include numerous interconnecting parts that require precise fits and positioning to interact with each other to extend and retract the bumpers. Gates are also known that utilize actuating mechanisms that include a complex arrangement of links, cranks, pull rods and springs that are interconnected to a pull handle. An example of such an actuating mechanism is disclosed in U.S. Pat. No. 5,052,461.
Another disadvantage associated with known gates is an inability of the moveable plungers to independently compensate for different spacings between each bumper and the side member of an opening. Different spacings can result from various factors such as surface irregularities of the vertical members of an opening, an opening having nonparallel vertical members and the like. Conventionally, known gates use rigid connections between the bumpers and actuating mechanism that can result in a bumper making minimal or no contact with a vertical member of the opening or a bumper exerting a very high force against the vertical member of an opening. U.S. Pat. No. 5,052,461, discussed above, is an example of a gate that incorporates a pair of spring loaded plungers to accommodate irregular door frames and control the forces exerted by the plungers. However, the actuating mechanism incorporated in this gate is a complex assemblage of parts that is expensive to manufacture.
Accordingly, it is an object of the present invention to provide an improved safety gate that overcomes these and other disadvantages associated with known gates.
SUMMARY OF THE INVENTION
In an illustrative embodiment of the invention, the safety gate comprises a panel including a vertical outer leg, at least one bumper movably mounted on the outer leg in a horizontal direction, an actuator slidably mounted for vertical movement in the panel between a raised position and a lowered position, at least one push rod connected to the actuator and mounted for horizontal movement in the panel in alignment with and independent of the bumper, and at least one spring disposed between the bumper and the push rod. The panel in use is positioned within the opening, and the bumper is moved between an extended position to secure the panel in the opening and a retracted position to release the panel from the opening. One end of the push rod is connected to the actuator and its opposite end is horizontally spaced from the bumper to establish a buffer zone therebetween. In operation, the push rod is extended toward the bumper when the actuator is lowered and is retracted away from the bumper when the actuator is raised. The spring is disposed in the buffer zone between the push rod and the bumper to urge the bumper toward the extended position when the actuator is lowered.
The gate may also include a second spring disposed between the outer leg of the panel and the first spring to urge the bumper toward the retracted position when the actuator is raised. The springs can be compression springs that have spring constants that are different from each other. While an illustrative embodiment of the gate is shown with a pair of movable bumpers, push rods and springs, the gate may include fewer or greater numbers of bumpers, push rods and springs. If multiple movable bumpers are used, the springs may independently urge the bumpers toward their respective extended or retracted positions.
The panel may include one or more stops to limit the horizontal movement of the bumper, push rod, or both. The panel may be made up of a pair of gate sections that are slidably connected together to allow the gate width to be adjusted to accommodate openings, such as passageways of various widths. A locking device may be provided to secure the gate sections in a desired width.
The gate may also include a handle carried on top of the actuator to lower and raise the actuator to respectively extend and retract the bumper or bumpers. A handle latching device may be provided for releasably retaining the handle and actuator to hold the bumpers in the extended position.
As another aspect of the invention, the safety gate comprises a panel that includes a vertical outer leg, at least one bumper mounted on the outer leg and movable in a horizontal direction, an actuator slidably mounted for vertical movement in the panel, at least one push rod coupled to the actuator and mounted for horizontal movement in the panel in alignment with the bumper, and at least one pair of springs, one of the springs coupling the push rod to the bumper and the second spring disposed between the first spring and the outer leg. The panel in use may be positioned within the opening, and the bumper may be moved between an extended position to secure the panel within the opening and a retracted position to release the panel from the opening. To operate the gate, the push rod may be extended toward the bumper by lowering the actuator which causes the first spring to urge the bumper toward the extended position. Conversely, the push rod may be retracted away from the bumper by raising the actuator which causes the second spring to urge the bumper toward the retracted position.
As a further aspect of the invention, the safety gate comprises a pair of generally flat gate sections, a locking device joining the gate sections together, a pair of horizontally extending fixed bumpers mounted on the outer frame member of the first gate section and positioned to engage one side of a passageway in which the gate is to be mounted, a pair of horizontally extending movable bumpers mounted on the outer frame member of the second gate section and positioned to engage the other side of the passageway, and a pair of push rods that are slidably mounted for horizontal movement in the second gate. The push rods are in alignment with and connected to the pair of movable bumpers for extending and retracting them. The gate also includes an actuator that is slidably mounted for vertical movement in the second gate section. The actuator is connected to each push rod so as to drive the movable bumpers toward the extended position to secure the gate when the actuator is in a lowered position and to retract the movable bumpers to release the gate when the actuator is in a raised position. The gate sections are slidably connected together in face-to-face relationship and have an effective combined width that may be varied to obstruct passageways of different widths. The locking device enables the sections to be secured in a fixed relationship to one another so that their combined effective width will not vary.
BRIEF DESCRIPTION OF THE DRAWINGS
It should be understood that the drawings are provided for the purpose of illustration only and are not intended to define the limits of the invention. The foregoing and other objects and advantages of the present invention will become apparent with reference to the following detailed description when taken in conjunction with the accompanying drawings in which:
FIG. 1 is a front elevational view of a safety gate of the present invention mounted in a doorway;
FIG. 2 is a rear view of the safety gate of FIG. 1;
FIG. 3 is a left side elevational view of the safety gate of FIG. 1;
FIG. 4 is a right side elevational view of the safety gate of FIG. 1;
FIG. 5 is a bottom view of the safety gate of FIG. 1;
FIG. 6 is a top view of the safety gate of FIG. 1;
FIG. 7 is a partial, fragmentary cross-sectional rear elevational view of the gate locking mechanism of the safety gate of FIGS. 1-6 taken along section line 7--7 in FIG. 6 shown with the gate locking mechanism in the locked position;
FIG. 8 is a partial, fragmentary cross-sectional rear elevational view similar to FIG. 7 shown with the gate locking mechanism in the unlocked position;
FIG. 9 is an enlarged front view of the elongated front well and rack for the width adjustment locking assembly;
FIG. 10 is an enlarged cross-sectional top view of the width adjustment locking assembly of the safety gate taken along section line 10--10 in FIG. 1;
FIG. 11 is an enlarged fragmentary rear view of an extendable bumper of the safety gate of FIGS. 1-6 illustrating the bumpers in a fully retracted position;
FIG. 12 is an enlarged fragmentary rear view of the handle latching device of the safety gate of FIGS. 1-6 illustrating the handle in a locked position; and
FIG. 13 is an enlarged fragmentary rear view of the handle latching device of the safety gate of FIGS. 1-6 illustrating the handle in an unlocked position.
DETAILED DESCRIPTION
The child safety gate shown in FIGS. 1-6 is comprised of two major gate sections, including a rear gate section 20 and a front gate section 22, disposed in face-to-face relationship with one another and slidably connected together so that the effective total width of the gate may be adjusted to accommodate the various widths of passageways to be obstructed by the gate. The rear gate section 20 carries a pair of stationery bumpers 24 and 26 on the vertical outer leg 28 of its frame 30. A pair of extendable bumpers 32 and 34 are carried on the vertical outer leg 36 of the frame 38 of the front gate section 22. The extendable bumpers 32 and 34 are each mounted on the end of a push rod 40 (FIGS. 7 and 8) that is in turn mounted for translational motion on the front gate section 22. The push rods 40 are connected by links 42 to a vertically movable actuator 44 that carries a handle 46 at its upper end and which is also mounted on the front gate section 22. It is to be appreciated that a greater or lesser number of stationary bumpers 24 and 26 and extendable bumpers 32 and 34 than that shown in the illustrative embodiment may be utilized to secure the gate in a passageway.
Gross adjustments of the effective width of the gate are made by moving the gate sections 20 and 22 with respect to one another so as to position the fixed bumpers 24 and 26 and the movable bumpers 32 and 34 essentially in contact with the sides of the passageway in which the gate is to be installed. The extendable bumpers 32 and 34 should be in their retracted position during gross adjustment of the gate width. The gross adjustment is made by loosening the knob 48 of the width adjustment locking assembly 50 and moving the gate sections 20 and 22 in their respective planes so as to place the bumpers carried by each gate section against the side of the passageway. When that is accomplished, the knob 48 is tightened to hold the gate sections in fixed position with respect to one another. Thereafter, the actuator 44 is depressed by means of the handle 46 so as to move the push rods 40 in the horizontal direction toward the outer leg 36 of the frame 38 of the front gate section 22 and to drive the bumpers 32 and 34 firmly against the side of the passageway. That action causes the bumpers to be compressed against the sides of the passageway so as to firmly hold the gate assembly in position. To remove the gate, the handle 46 on the actuator 44 is released which enables the handle and actuator to be raised, and that in turn retracts the push rods 40 so as to reduce the pressure on the bumpers. The various elements of the gate are described in greater detail below.
The rear gate section 20 includes the rear frame 30, which defines the outer extremities of the rear gate section 20, and grating 60 which is separated into upper and lower sections by a frame crossbar 62 that extends horizontally between the vertical outer leg 28 and the vertical inner leg 64. The grating 60 is made up of an array of elliptical apertures 66 that allow the free flow of air through the gate but are small enough so as to preclude even a small child from putting a hand or foot through the mesh.
The upper and lower horizontal legs 68 and 70 of the frame 30 each are provided with an elongated slot 72 that extends substantially from the outer leg 28 to the inner leg 64 of the frame. As shown in FIG. 2, each slot 72 is provided with an enlarged opening 74 at its end adjacent the stationary bumpers 24 and 26 so as to enable the head of lock posts 117, as described below, carried by the front gate section 22 to be inserted through the opening 74 and into the slots 72 to thereby hold the gate sections 20 and 22 together.
As shown in FIGS. 1 and 9, the crossbar 62 also has an elongated slot 76 that extends across substantially the length of the crossbar 62 and is disposed in a shallow elongated front well 78. The base wall 80 of the front well 78, through which the slot 76 is formed, is shaped with a rack 82 that spans the slot 76. The rack 82 is comprised of closely spaced teeth 84, each having a steep face 86 to assist in locking the rear gate section 20 to the front gate section 22.
Each of the stationary bumpers 24 and 26 has a base 88 and a cap 90. Each base 88 is integrally molded on the rear gate section 20 and the caps 90 are separately molded of a pliable plastic material, such as polyvinyl chloride (PVC), that will not mar the surface of the passageway sides when engaged by the bumpers. The caps 90 are snapped onto the bases 88 and once attached are not intended to be removed.
Referring to FIG. 2, a rear well 100, somewhat smaller than the front well 78, is disposed on the back of the rear gate section 20 opposite the front well 78, and is defined by an endless flange 102 and the base wall 80. The slot 76 which extends through the bottom wall 80 is, of course, exposed on both sides of the gate section 20. Unlike in the front well 78, the rear surface of the base wall 80 is smooth and does not carry a rack or any other irregular surface to allow a nut-like fastener 131 to slide along the rear well 100.
The front gate section 22 is approximately the same size as the rear gate section 20, and its frame 38 includes upper and lower horizontal legs 110 and 112, a crossbar 114 and a vertical inner leg 116, along with the vertical outer leg 36.
To stabilize the connection between the rear and front gate sections 20 and 22, lock posts 117 are integrally formed on the rear surface of each of the upper and lower horizontal legs 110 and 112 of the frame 38 of the front gate section 22. The lock posts 117 are sized so they extend into and through the slots 72 on the rear gate section 20 and enter the slots 72 through the enlarged openings 74 so as to hold the two sections in sliding relationship with one another. Each lock post includes a head 118 that has a diameter that is greater than the width of the slots 72 to maintain the posts in the slots as the gate sections are adjusted in their respective planes to a desired width. The narrowest effective width of the gate assembly is achieved when the gate sections overlie one another so that their vertical inner and outer legs are aligned. The effective width of the gate may be increased by moving the gate sections with respect to one another so that the outer legs of each section move apart.
As shown in FIGS. 7, 8 and 10, the crossbar 114 carries a boss 120 adjacent the vertical inner leg 116 of the frame whose diameter is slightly smaller than the width of the front well 78 of the rear gate section 20. The rearward most surface of the boss 120 is serrated with teeth 122 which are designed to register with the teeth 84 of the rack 82 in the front well 78. Thus, when the gate sections are slid horizontally with respect to one another, the boss 120 moves along the front well 78 and the respective teeth 122, 84 on the boss 120 and rack 82 slide over one another. The front face of the front gate section 22 has a counterbore-type recess 124 aligned with the boss 120 that receives the knob 48 that forms part of the width adjustment locking assembly 50. The knob 48 carries a threaded stem 128 that extends through the opening 130 in the boss 120. When the gate is assembled, the stem 128 extends through the slot 76 in gate section 20 and engages the nut-like member 131 disposed in the rear well 100 of the crossbar 62 in the rear gate section 20. The elongated shape of the nut-like member 131 prevents it from rotating and, therefore, the stem 128 may be threaded into and out of the threaded hole 132 of the nut 131 so as to loosen and tighten the gate sections to one another. It will be appreciated that the teeth 122 carried on the boss 120 have generally vertical faces 134 which engage the generally vertical faces of the teeth 84 on the rack 82 so that the gate sections are held very firmly together and cannot slide relative to each other so as to shorten the effective width of the gate assembly when the knob 48 is tightened. However, the formation of the teeth both on the boss 120 and the rack 82 allows the gate sections to move rather freely so as to increase their effective width when the knob 48 is loosened.
In FIGS. 7, 8 and 11-13, the locking mechanism including the movable bumpers 32 and 34 along with the push rods 40, the actuator 44 as well as the handle 46 and the handle latching device 162 incorporated into the front frame 38 are shown in detail. As the push rod assemblies are identical, only one is described. Referring first to FIGS. 7 and 8, it will be noted that the push rod 40 includes a main translating link 140 which is captured within a guide 142 secured to one of the horizontal legs of the frame 38. The translating link 140 carries a link connector 144 at its end opposite the actuator 44 that engages one end of a first compression spring 146. The movable bumper 32 (34) is carried by a bumper stem 148 that includes a stem connector 149 and stem flange 152 which engages the other side of the first compression spring 146. A second compression spring 150 surrounds the bumper stem 148 and bears at one end against the stem flange 152 opposite the first compression spring 146 and at its other end against a flange 154 formed on the rear surface of the outer vertical leg 36 of the frame 38. The second spring 150 serves to urge the stem 148 toward the retracted position so as to retract the bumper 32 (34) while the first spring 146 serves as an override to allow the translating link 140 to push the bumper 32 (34) into the extended position against the side of the passageway closed by the gate. The lengths of the translating link 140 and the bumper stem 148 are sized to maintain a buffer zone between the link connector 144 and the stem connector 149 so that they do not contact each other even when the bumper stem 148 is fully retracted into the housing 160 and the translating link 140 is fully extended into the housing 160. The buffer zone allows the first spring 146 to act as a cushion so as to absorb any override of the translating link 140 as it pushes outwardly against the bumper stem 148 to extend the bumper. A significant advantage to coupling the translating link 140 to the bumper stem 148 with the first compression spring 146 and a buffer zone therebetween lies in the ability of the moveable bumpers 32 and 34 to individually accommodate different spacings between the outer rail 36 of the front gate section 22 and the side of a passageway without subjecting the components of the locking mechanism to undue stresses. Similar to the stationary bumpers 24 and 26, each extendable bumper 32 and 34 includes a bumper cap 90 snapped onto the bumper stem 148.
The first and second springs 146 and 150 should be sized to ensure that sufficient forces are produced to properly secure the gate in a passageway when the actuator 44 is lowered and to fully retract the extendable bumpers when the actuator 44 is raised. In the illustrative embodiment shown, each extendable bumper 32 and 34 preferably exerts from approximately 58 lbs to approximately 86 lbs against the side of the passageway when the actuator 44 is lowered to extend the bumpers. This force can be produced using a first compression spring 146 having a spring constant of approximately 115 lbs/in (pounds per inch) which is compressed from approximately 0.5 inches to approximately 0.75 inches between the translating link 140 and the bumper stem 148 when the actuator 44 is lowered. Because the first compression spring 146 does not include a preload when the actuator 44 is raised to release the gate, the second compression spring 150 needs only to produce enough force to overcome frictional forces exerted on the bumpers 32 and 34 to retract them. Sufficient force can be produced using a second spring 150 having a spring constant of approximately 4.1 lbs/in and which is slightly preloaded when the actuator 44 is raised. The difference in spring constants also ensures that the retaining force produced by the first spring 146 is not significantly offset by the opposing force of the second spring 150.
Each of the springs 146 and 150 may be made from music wire suitable for providing the desired spring characteristics. For example, the first spring 146 may have a wire diameter of 0.125 inches, an outer diameter of 0.97 inches and a free length of 1.75 inches. The second spring 150 may have a wire diameter of 0.062 inches, an outer diameter of 0.97 inches and a free length of 4.0 inches. It should be appreciated that the particular spring constants and sizes are exemplary only and other materials, sizes and spring characteristics may be used in accordance with the present invention.
A housing 160 is secured to each horizontal leg 110 and 112 of the front frame 38 adjacent the outer leg 36 to capture and retain the bumper biasing components, as described above, to the frame. As shown in FIGS. 7, 8 and 11, the outer edge of the bumper stem flange 152 engages the inner wall of the housing 160 and the flange 154 on the outer leg 36 of the frame engages the outer surface of the stem 148 to hold the stem in a horizontal position as it is retraced and extended. Similarly, the translating link connector 144 includes a connector flange 164 which also engages the inner wall of the housing 160 and a rear flange 166 of the housing 160 to limit the movement of the translating link 140 to the horizontal direction and to ensure that the connector 144 remains captured in the housing 160. To limit the horizontal travel of the stem 148 and the translating link 140, two groups of elongated horizontal stops extend inwardly from the inner wall of the housing 160. A first group of stops 168 is disposed between the outer leg flange 154 and the stem flange 152 so as to engage the stem flange 152 and limit the extension of the stem 148 and moveable bumper 32 (34) from the housing. A second group of stops 169 is disposed between the stem flange 152 and the connector flange 164 so as to engage the stem flange 152 and limit the retraction of the stem 148 into the housing and to also limit the extension of the translating link connector 144 into the housing 160. The limitations on the travel of the stem 148 and translating link 140 ensure that the buffer zone between them is maintained and the first and second springs 146 and 150 generate sufficient biasing forces without being over stressed. It should be appreciated that the actual number and shape of the stops can be varied.
Referring to FIGS. 7 and 8, the actuator 44, which is an elongated and generally rectangular member, is disposed in a vertical channel defined by vertically extending sidewalls 170 integrally formed in the front frame 38. The actuator 44 is retained to the front frame 38 by a fastener 172, such as a shoulder screw, which is disposed in an elongated recess 174 having an elongated slot 176 therethrough. A boss (not shown) extends away from the rear surface of the front gate section 22 and through the slot 176 to guide the actuator 44 and to ensure that the shoulder screw cannot be tightened against the base of the recess 174 so that the actuator 44 can easily slide within the vertical channel. Each translating link 140 is coupled to the actuator by a link 42 pivotally connected to both of them. The actuator 44 has a pair of curved recesses 180 that receive the links 42 when the actuator is raised to the unlocked position. The recesses 180 allow the links 42 and the actuator 44 to move within a compact arrangement to fully extend and retract the bumpers. The links 42 transform the vertical movement of the actuator 44 into horizontal movement of the translating links 140 so as to extend and retract the bumpers 32 and 34 as the actuator 44 is respectively moved downward and upward.
The handle 46 is supported at the top end of the actuator 44 as a means to drive the actuator in the vertical direction. The upper horizontal leg 110 of the front frame 38 includes a generally U-shaped seat 182 which is contoured to receive the handle 46 in the lowered or locked position. The seat 182 includes vertical guides 184 disposed on opposing inner sidewalls 186 that are received in corresponding slots 188 on the outer sidewalls 190 of the handle 46 to guide the movement of the handle in the vertical direction.
As shown in FIGS. 12 and 13, a handle latching device 162 (only one is shown) is provided in each side of the handle 46 adjacent the vertical slot 188 as a means to lock the handle in the closed position to ensure that the moveable bumpers 32 and 34 cannot be inadvertently retracted to release the gate from the passageway. Because the handle latching devices 162 are identical, only one is described. It is to be appreciated that a single handle latching device 162 in one side of the handle 46 may be utilized to lock the handle.
Each handle latching device 162 includes an L-shaped latch 192 rotatably mounted on a pivot 194 in an upper corner of the handle 46. The latch 192 includes a vertical locking arm 196 extending downwardly from the pivot 194 and a horizontal lever 198 extending into the handle away from the pivot 194. A locking barb 200 disposed on the free end of the locking arm 196 opposite the pivot 194 engages the lower lip 202 of the guide 184 to lock the actuator 44 when the handle 46 is pushed down into the seat 182. The barb 200 has a cam surface 204 which engages the outer surface 206 of the guide 184 to rotate the latch 192 as the handle 46 moves downward. The locking arm 196 is biased to the vertical locking position by a spring 208 that is connected between an ear 210 of the latch 192 extending above the pivot 194 and a fixed post 212 on the handle 46. To unlock the latch, a trigger 214, which is shown as an elongated bar mounted in the handle 46, is squeezed to engage and rotate the lever 198 about the pivot 194. Rotation of the lever 198 similarly causes the locking arm 196 to rotate so that the barb 200 disengages the guide 184, and the handle 46 can be pulled in an upward direction. When the trigger 214 is released, the force of the spring 208 causes the latch 192 to rotate in the opposite direction to place the locking arm 196 in the vertical locking position.
The handle latching device 162 itself can be locked to prevent a child from unlocking the actuator 44 and disengaging the movable bumpers 32 and 34 from the passageway. To lock the handle latching device, the handle 46 is pulled upwardly away from the seat 182 without squeezing the trigger 214 so that the locking barb 200 is firmly seated against the lower lip 202 of the guide 184. The interaction between the locking barb and the lower lip maintains the latch in a locked position thereby preventing the trigger 214 from being depressed to pivot the latch. This locking capability can be enhanced with a recess or a detent (not shown) on the lower lip 202 of the guide 184 that respectively receives or mates with the locking barb. To unlock the trigger 214 and the handle latching device 162, the handle 46 is pushed downwardly into the seat 182 to disengage the locking barb 200 from the lower lip 202 prior to squeezing the trigger so that the latch 162 can pivot when the trigger is depressed.
The various components of the safety gate preferably are molded of a suitable plastic material, such as a polypropylene copolymer or acrylonitrile-butadiene-styrene (ABS). Generally, the components associated with the locking functions of the gate, such as the actuator 44, links 42, translating links 144, handle latch 192 and width adjustment locking assembly 50, are preferably molded of ABS so these parts have sufficient rigidity. Other components, such as gate frames 30 and 38, guides 142, bumper stems 138 and housings 160, are preferably molded of a polypropylene copolymer. It should be appreciated that other processes and materials may be used to make a safety gate in accordance with the present invention.
Having described a particular embodiment of the invention in detail, various modifications and improvements will readily occur to those skilled in the art. Such modifications and improvements are intended to be part of this disclosure and within the spirit and scope of the invention. Accordingly, the foregoing description is by way of example only and the invention is defined by the following claims and their equivalents. | A safety gate for use in obstructing doorways, passageways and similar openings to restrict the movement of children and the like. The safety gate includes a panel that can be readily secured in and removed from the opening by extending and retracting one or more movable bumpers mounted on an outer rail of the panel. Each movable bumper is urged to the extended position in a horizontal direction by a spring that connects the bumper to a push rod which is mounted in the panel for horizontal movement in alignment with the bumper. Each push rod is connected to an actuator that is mounted in the panel for vertical movement between a lowered position and a raised position. Each movable bumper is independently urged to the extended position by its spring when its corresponding push rod is driven toward the bumper by lowering the actuator. The spring can be a compression spring having one end connected to the bumper and its opposite end connected to the push rod. Additional springs can also be provided to retract the bumpers when the actuator is raised. The panel can include a pair of gate sections that slide relative to each other to vary the effective width of the gate so as to correspond to the width of an opening that is to be obstructed by the gate. A panel locking device can be provided to secure the sections together so that the desired width does not vary. A locking handle can be carried on the top end of the actuator to easily move the actuator. A handle latching device can be provided to retain the handle and actuator in the lowered position to hold the bumpers in the extended position. | 4 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a Section 371 of International Application No. PCT/EP2013/075754, filed Dec. 6, 2013, which was published in the German language on Jun. 19, 2014, under International Publication No. WO 2014/090693 A1 and the disclosure of which is incorporated herein by reference.
BACKGROUND OF THE INVENTION
The present invention relates to an irradiation device for irradiating plants, comprising a carrier element defining a culture plane E for cultivating the plants, multiple irradiation sources for irradiating the plants with visible and/or ultraviolet radiation, and multiple infrared emitters for irradiating the plants with infrared radiation.
The present invention further relates to an emitter module for irradiating plants with infrared radiation for use in an irradiation device.
For the breeding and cultivation of plants, for example in greenhouses and in tiered crop growing, artificial light sources are used. The emission spectrum of these light sources is usually adapted to the absorption spectrum of the green leaf pigment of chlorophyll and carotenes
Several natural pigments that are essential to the photosynthesis process are combined under the terms chlorophyll and carotene. The absorption spectra of these pigments dissolved in solvents have two pronounced absorption maximums, namely one absorption maximum in the violet and blue spectral range between 400 nm and 500 nm, and another absorption maximum in the red spectral range of visible light between 600 nm and 700 nm.
To ensure efficient irradiation of plants, the emission spectrum of artificial light sources for irradiating plants has large radiation components in both wavelength ranges specified above.
As light sources, for example, gas discharge lamps or light emitting diodes (LEDs) are used. Gas discharge lamps consist of a discharge chamber filled with a filling gas and in which two electrodes are arranged. A gas discharge associated with the emission of visible radiation takes place in the discharge chamber as a function of a voltage applied to the electrodes. The wavelength of the emitted radiation can be influenced by a selection of the filling gas and adapted to the absorption spectrum of the chlorophyll, for example by an appropriate doping of the filling gas. In contrast, LEDs emit light only in a limited spectral range, so that, for generating an emission spectrum adapted to the absorption spectrum of the chlorophyll, multiple LEDs of different wavelengths must be combined with each other. For example, from U.S. patent application publication 2009/0251057 A1, an artificial light source is known having multiple LEDs in which, for generating artificial sunlight, light emitting diodes having different emission spectra are combined.
However, efficient cultivation of plants depends not only on the excitation of photosynthesis, but also on the transport of water and nutrients in the plant and on the carbon dioxide assimilation. Both the water and nutrient transport in the plant and also the carbon dioxide assimilation are influenced by the stomatal apparatus of the plant. By the stomata of the plant, the plant regulates the gas exchange with the ambient air, in particular the absorption of carbon dioxide from the air and the emission of oxygen to the air. The water balance of the plant is also influenced by the opening width of the stomata. Thus, opened stomata lead to increased water evaporation that generates transpiration suction, so that, overall, the transport of water and nutrients (sap flow) from the roots to the leaves is increased.
The opening width of the stomata can be regulated by several factors that include, for example, the temperature, the availability of water, the carbon dioxide concentration in the leaf interior, and the absorption of light. By a targeted irradiation with infrared radiation, the stomata width and thus the effectiveness of photosynthesis can be regulated.
In International patent application publication WO 2010/044662 A1, an irradiation device for plants is proposed having a chamber in which, in addition to the radiation sources for irradiating the plants with visible or ultraviolet radiation, multiple infrared emitters arranged on a side wall of the chamber are provided for irradiating the plants with infrared radiation. By the infrared emitters, the leaves of the plants are heated such that the stomata open, so that a stimulation of the exchange processes of the plants with their surroundings is achieved.
Due to the lateral arrangement of the infrared emitters, the individual plants are irradiated as a function of the their planted position on the culture plane each at a different spacing to the infrared emitters and are therefore irradiated to different degrees. It has been shown that, in particular, compared with the inner areas of the culture area, the outer areas of the culture area are exposed to higher irradiation intensities. To ensure efficient cultivation of the plants, however, in principle uniform growth of the plants and thus homogeneous irradiation of all plants is desirable.
With a lateral arrangement of the infrared emitters in relation to the cultivation surface, a large number of emitters is required, which must have a low power output in order not to damage the plants in the outer area of the culture area due to excessive heating. Infrared emitters, however, typically have a high power output; emitters of low power output are complicated to make and have only a limited service life.
In addition, the lateral arrangement of the infrared emitters also contributes to irradiation and heating of the other components provided in the irradiation device, for example the electrical cables and mounting elements for the radiation sources, and also the radiation sources provided in the irradiation device, whereby the service lives of these components are shortened due to the irradiation. A lateral arrangement of the infrared emitters is therefore associated with high operating costs.
BRIEF SUMMARY OF THE INVENTION
The invention is therefore based on the object of providing an irradiation device for irradiating plants, which has a long service life and ensures, in addition to irradiating plants with ultraviolet and/or visible radiation, a uniform irradiation of the plants with infrared radiation, without unnecessarily negatively affecting the irradiation with ultraviolet and/or visible radiation and, in addition, requires a small number of infrared emitters in relation to the culture area.
The invention is further based on the object of providing an emitter module for irradiating plants with infrared radiation, which is designed for optimal use in an irradiation device for irradiating plants.
Finally, the invention is also based on the object of minimizing losses in the conversion of electrical energy into infrared radiation, losses in the steering of the infrared radiation to the plants to be irradiated, mutual shading of light sources, and other energy losses.
With respect to the irradiation device, according to the invention this object is solved, starting from a device of the generic type described at the outset, in that the infrared emitters are designed for a temperature from 800° C. to 1800° C. and each has a cylindrical emitter tube having an emitter tube length in a range from 50 mm to 500 mm, and that the emitter tubes extend parallel to each other in an emitter zone Z placed above the culture plane E, wherein the infrared emitter population density in relation to the surface area of the culture plane E is in a range between 0.2 m −2 and 1.0 m −2 , and irradiation areas of adjacent infrared emitters overlap on the culture plane E, in that the average irradiation intensity on the culture plane E is between 10 W/m 2 and 100 W/m 2 with a maximum fluctuation range of 50%, and that a reflector directed toward an installation space B is allocated to a top side of the emitter tube.
Sunlight, which plants need under natural conditions for their growth, has radiation components of ultraviolet, visible, and infrared radiation. For simulating natural growth conditions, the artificial irradiation device therefore also has infrared emitters, in addition to emitters for generating ultraviolet and/or visible radiation (hereinafter also called UV and VIS emitters, for short). By the use of these emitter types, the plants are provided, under artificial cultivation conditions, on one hand with the radiation required for photosynthesis and, on the other hand, the opening width of the leaf stomata can be regulated by the infrared radiation, so that an optimum transport of water and nutrients is set within the plant. By these measures, quick plant growth and high productivity are ensured.
To ensure the most uniform possible plant growth, however, it is necessary to irradiate the plants as uniformly as possible, that is, with a nearly constant irradiation intensity. This applies, in particular, also for the irradiation of plants with infrared radiation. A local infrared irradiation intensity that is too high leads to damage of the affected plants. In contrast, too low an irradiation intensity reduces the effect of the infrared radiation on the opening width of the stomata; it leads to too little plant growth.
In the irradiation device according to the invention, the infrared emitters are arranged in an emitter zone Z placed above the culture plane E. Here, it is important that the infrared emitters generate an overall uniform irradiation area on the culture plane E. Infrared emitters arranged exclusively laterally of the irradiation surface can thus be eliminated.
To achieve an overall uniform irradiation area on the culture plane E, the infrared emitters are arranged in the emitter zone Z and distributed uniformly relative to each other, such that their emitter tube longitudinal axes run parallel to each other. The parallel arrangement of the emitter tubes ensures a two-dimensional emission of the infrared radiation, which is especially suitable for uniform irradiation of a plane, for example, a plane of the plants defined by the plant growth or the culture plane.
With the uniform distribution of the infrared emitters in the emitter zone Z, it does not have to be taken into account that the UV and VIS emitters experience shading on the culture plane. The goal is thus not only a uniform infrared irradiation, but also a minimization of the shading of the UV and VIS radiation on the culture plane E.
Above the emitter tube, the irradiation device according to the invention has an installation space B. In this installation space, a plurality of components are arranged that are needed for the operation of the irradiation device, for example electrical cables or mounting elements for the infrared emitters or other radiation sources. Therefore, in principle it is desirable to prevent excessive heating of the components of the installation space by infrared/thermal radiation.
An excessive heating of the installation space and the components located therein is reduced according to the invention in that the emitter tube has, on its top side, a reflector that reduces the spreading of the emitted infrared radiation in the direction of the installation space. Because such a reflector, however, could simultaneously negatively affect the radiation spreading of the UV/VIS radiation emitted by the UV and VIS emitters arranged, for example, in the emitter zone, a largest possible radiation spreading of the UV and VIS emitter is ensured in that, in relation to the culture plane E, the lowest possible number of infrared emitters is used, and the reflector is shaped so that shading of the UV/VIS radiation is reduced.
In addition to minimal shielding of the UV/VIS radiation, the emission characteristics of the infrared emitter plays an important role. It should ensure that the infrared radiation is not just simply reflected downward, but instead is distributed over a wide irradiation range.
A uniform irradiation of the culture plane E with simultaneously smallest possible number of infrared emitters is achieved according to the invention, in that the reflector is shaped above the emitter tube so that the infrared radiation emitted from the area above the horizontal through the center of the heating coil is deflected into areas farther away from the radiation module.
Conventional reflectors, for example parabolic or hyperbolic reflectors, do not fulfill this function, because they reflect the radiation, in particular, into areas directly below the emitter tube.
A low emitter number goes along with a low number of reflectors. These can have larger dimensions with less radiation shielding at the same time, so that they can better contribute to uniform irradiation in the culture plane E. An optimal range for the number of infrared emitters in relation to the culture area is between 0.2 m −2 and 1.0 m −2 . For a number of less than 0.2 infrared emitters per square meter, a uniform radiation distribution can be achieved only with difficulty, for example with large reflectors that then obstruct the radiation of the UV and VIS emitters also located in the emitter zone Z. A number greater than 1.0 infrared emitters per square meter results in reduced efficiency of the IR irradiation, because very small infrared emitters have a significantly lower conversion efficiency of electrical energy into infrared radiation. In addition, the mounting and maintenance expense increases with the number of units.
A low emitter number in relation to the culture plane also enables the use of smaller, but more powerful infrared emitters that have, in comparison with larger and less powerful infrared emitters, a higher conversion efficiency, so that they have lower heat losses and also longer service lives. For this reason, the length of the cylindrical emitter tubes is in a range from 50 mm to 500 mm.
The longer service life of such emitters is achieved in that the individual emitters are operated at the highest possible voltages approximately in a range of 24 V up to grid network. In this way, for example, only a small number of transformers is needed, so that heat losses caused by transformers are kept low. In this voltage range, larger, but less powerful emitters can be operated, however only at low current intensities, which makes the use of straight filaments having very small wire diameters (less than 0.4 mm) necessary. These filaments typically have low mechanical stability, inhomogeneous temperature distribution, and short service life.
To achieve uniform irradiation of the culture plane, with the use of fewer emitters, an overlapping of the irradiation areas of adjacent emitters is required, so that the average irradiation intensity has a maximum fluctuation range of 50%. The fluctuation range is understood to be the maximum deviation of the actual irradiation intensity at one point of the culture plane E from the average irradiation intensity. According to the invention, the actual irradiation intensity deviates at most by ±50% from the average irradiation intensity on the culture plane E. The deviation from the average irradiation intensity on the culture plane preferably equals 20%, especially preferred 10%. For optimum growth of the plants, the emission spectrum of the infrared emitters is also significant. The absorption spectrum of plants is marked by high absorption in the wavelength range below 700 nm and also above 2.5 μm. In a range between 0.7 μm and 2.5 μm, a basic absorption of approximately 5% and a nearly undirected scattering is observed. Radiation having wavelengths in this range is suitable for penetrating the top-most leaf layers of a plant; it is basically also available for irradiation of the lower leaf layers, but is absorbed only at lower percentages. It has been shown that an optimum plant growth is achieved if the heating filament is designed for a temperature from 800° C. to 1800° C., preferably for a temperature in a range from 850° C. to 1500° C.
Emitters that have a filament temperature in a range named above at a nominal voltage emit radiation having an intensity maximum at wavelengths in a range between 0.7 μm and 3.5 μm.
Here, a difference must be distinguished between applications that target an optimum irradiation only of the upper leaf layers and those in which the lower leaf layers are also to be irradiated. The use of medium-wavelength thermal infrared emitters is advantageous, if nearly the entire radiation is to be absorbed or reflected on the top-most leaf layer. Such emitters have, at a nominal voltage, a filament temperature in a range between 800° C. and 1000° C. Short-wave thermal infrared emitters having a filament temperature at a nominal voltage in a range between 1400° C. and 2200° C., preferably between 1400 and 1800° C., are especially suitable for penetrating the upper leaf layers.
Radiation generated at filament temperatures in the transition range between 1000° C. and 1400° C. is produced by a mixture of the two mechanisms.
In a first advantageous embodiment of the device according to the invention, it is provided that the average irradiation intensity on the culture plane is 10 W/m 2 to 50 W/m 2 .
The required average irradiation intensity on the culture plane depends on the type of plant to be cultivated and other environmental conditions. It has been shown that for many plant types, an irradiation intensity in a range of 10 W/m 2 to 50 W/m 2 leads to accelerated growth and thus to shorter average durations of stay of the plant in the cultivation chamber.
In another similarly preferred embodiment of the irradiation device according to the invention, it is provided that multiple infrared emitters are arranged one behind the other in the direction of their longitudinal axes, and that adjacent infrared emitters have, in the direction of their longitudinal axis, a spacing from each other between 0.9 m and 2.3 m, preferably between 1.1 m and 1.7 m.
To ensure uniform irradiation of the culture plane both with ultraviolet/visible radiation and also with infrared radiation in the most cost-efficient way possible, properties in conflict with each other or mutually affecting each other must be optimized, such as emitter power output, emitter size, and emitter population density. In principle, a low emitter density of the infrared emitters is desirable. A spacing between adjacent infrared emitters of less than 0.9 m, however, leads to a comparatively high emitter density, which is associated with low nominal output power per emitter and high installation and operating costs. If adjacent infrared emitters in the direction of their longitudinal axes have a spacing of more than 2.3 m, a uniform irradiation of the culture plane with infrared radiation is to be achieved only with difficulty.
Preferably, the infrared emitters are arranged in parallel rows, wherein adjacent rows run such that the infrared emitters of adjacent rows are arranged one next to the other.
In other words, the infrared emitters of adjacent rows are not offset “staggered” relative to each other, but instead begin and end—with equal length—at the same longitudinal positions of the illumination field within the emitter plane Z. In connection with the shape of the reflectors, this results in lower mutual influence and optimum homogeneous irradiation density on the plant plane.
In this context, it has also proven effective if adjacent infrared emitters arranged parallel to each other have a spacing from each other between 1 m and 3 m, preferably between 1.3 m and 2.5 m, especially preferred between 1.5 m and 1.8 m.
It has proven advantageous if the infrared emitters have a spacing from the culture plane of 1.0 m±0.5 m. For larger spacings, all of the dimensional and power specifications must be scaled accordingly.
The spacing of the infrared emitters and the culture plane influences the irradiation intensity and its distribution on the culture plane E. Depending on the type of plant, a spacing of the infrared emitters from the culture plane from 0.5 m to 1.5 m has proven effective. At a spacing of less than 0.5 m, plants can be irradiated only up to a low growing height. A spacing of the infrared emitters greater than 1.5 m negatively affects a compact construction of the irradiation device.
In a preferred modification of the irradiation device according to the invention, the reflector—viewed in the direction of the longitudinal axis—has a length in a range between 70 mm and 650 mm, preferably between 250 mm and 450 mm and a width in a range between 50 mm and 160 mm, preferably in a range between 80 mm and 130 mm.
The length of the reflector is adapted to the length of the emitter tube. A reflector length of less than 70 mm is only conditionally suitable for reducing an emission of infrared radiation in the direction of the installation space for an emitter tube length of the infrared emitter of at least 50 mm. For such short emitter tubes, a high number of infrared emitters is also required, which increases the failure probability, the installation expense, and the operating costs. A reflector having a length greater than 650 mm for a maximum emitter tube length of 500 mm leads to increased shielding of ultraviolet and/or visible radiation. The use of larger reflectors is also disadvantageous, because larger, but less powerful emitters operated at low current intensities then also must be used, which, in turn, makes the use of straight filaments having very small wire diameters (less than 0.4 mm) necessary. These filaments typically have poor mechanical stability, inhomogeneous temperature distributions, and short service lives.
The reflector width between 50 mm and 160 mm represents, for the same reasons, a suitable compromise between the shielding of the infrared radiation at the top and obstruction of the irradiation of the culture plane with ultraviolet and/or visible radiation.
In a similarly preferred modification of the irradiation device according to the invention, the reflector has a diffusely reflective surface.
A diffuse reflection of light takes place, for example, when light is incident on a rough surface having multiple surface elements having different orientations. A light beam incident on a diffusely reflective surface is reflected by the surface structure in many different directions, so that scattering produces is produced. Scattered light is suitable especially for generating uniform irradiation intensities, because maxima in the irradiation intensity are weakened, and the difference between minimum and maximum irradiation intensity on the culture plane E is reduced.
Here, it has proven effective, if the surface has a mechanically embossed structuring, for example produced from hammered aluminum. Suitable materials here are, for example, the MIRO®-DESSIN materials of ALANOD Aluminium-Veredlung GmbH.
A surface made of hammered aluminum has a diffusely reflective effect, leads to low radiation losses due to its rough surface structure, and is also simple and economical to produce.
In another preferred embodiment of the irradiation device according to the invention, it is provided that a first reflector strip running in the direction of the longitudinal axis is applied on a lateral area of the cover surface of the emitter tube.
A reflector strip applied on the lateral surface of the emitter tube prevents emission of infrared radiation in this area of the lateral surface. In this way, not only the lateral emission in the direction of the UV/VIS radiation sources also located in the emitter zone Z is reduced, but also the emission in the direction of the installation space, that is, depending on the size of the coverage angle. The mounting of reflector strips directly on the emitter tube allows a reduction of the reflectors above the emitter tubes for the same effectiveness, which concerns the reduction of the spreading of infrared radiation in the direction of the installation space. Smaller reflectors above the emitter tubes also negatively affect the visible radiation emitted by UV/VIS emitters mounted in the emitter zone Z to a lesser degree, so that a more uniform irradiation with ultraviolet and/or visible radiation is made possible.
It has proven advantageous if the reflector strip is made of gold, opaque quartz glass (silicon dioxide), or ceramic (for example aluminum oxide).
Reflector strips made of these materials are distinguished by strong reflection in the IR range, good chemical resistance, and, in some sections, high temperature resistance. They can also be easily applied on the emitter tube.
It has proven favorable, if the emitter tube has a circular cross section, wherein the reflector strip covers a circular arc of the emitter tube, which encloses, with a horizontal running through the filament center, a coverage angle between −40° and +40°, preferably −30° and +30°.
A reflector strip having such a coverage angle covers the emitter tube in the lateral direction above and below the horizontal. The coverage angle can be different above and below the horizontal, wherein optionally the amount of the coverage angle below the horizontal is preferably less than that above the horizontal. Therefore, because the reflector strip is arranged in the coverage angle range above and below the horizontal, on one hand an emission of infrared radiation having a flat emission angle with respect to the horizontal in the direction of the installation space and the UV/VIS radiation sources in the emitter zone and, on the other hand, a side, downward directed emission of infrared radiation having a flat emission angle can be reduced.
In a preferred construction of the last described embodiment of the irradiation device according to the invention, another reflector strip is applied on the lateral surface that is arranged mirror-symmetric to a vertical running through a filament center in relation to the first reflector strip.
Another reflector strip applied mirror-symmetric to the first reflector strip contributes to a symmetric and uniform irradiation of the culture plane.
It has proven effective if the reflector strip has a diffusely reflective surface.
Such a reflector strip contributes to a homogeneous irradiation of the culture plane E.
In a preferred modification of the irradiation device according to the invention, it is provided that, additional reflectors are arranged in each reflector plane laterally of the emitter tube, wherein the reflector planes enclose with the horizontal an angle between 25° and 70°, and their dimensions and spacing from the emitter tube are adjusted, such that they prevent direct emission of infrared radiation emitted by the emitter tube into a spatial area which, starting from a filament center of the emitter tube, is described by two planes, which each enclose, with the horizontal, an angle between −40° and +40°, preferably between −30° and +30°.
The two additional reflectors arranged laterally of the emitter tube are straight or shaped as a conical section. The lateral reflectors reflect the radiation from the region of a circular arc of the emitter tube that encloses, with a horizontal running through the center of the filament, an angle between −40° and +40°, preferably −30° and +30°. The lateral reflectors stand at an angle between 25° and 70° relative to the horizontal.
The coverage angle can be different above and below the horizontal, wherein optionally the amount of the coverage angle below the horizontal is preferably less than that above the horizontal. Therefore, because the lateral reflectors cover the angle range above and below the horizontal, on the one hand, an emission of infrared radiation having a flat emission angle in relation to the horizontal in the direction of the installation space and the UV/VIS radiation sources in the emitter zone can be reduced and, on the other hand, the lateral, downward directed emission of infrared radiation can be regulated by the setting of the reflector angle relative to the horizontal or by the type and shape of the conical section.
In a preferred construction of the last described embodiment of the irradiation device according to the invention, the lateral reflectors have a diffusely reflective surface.
In another preferred modification of the irradiation device according to the invention, it is provided that two side wings are connected to the reflector, wherein the side wings each enclose with the horizontal an angle in a range between 20° and 40°.
The side wings reduce, in particular, an emission of infrared radiation in the direction of the installation space. In addition, the side wings can also reduce a lateral emission of infrared radiation in the direction of the UV/VIS radiation sources in the emitter zone. Therefore, they contribute—as described above—to a high energy efficiency of the irradiation device.
It has proven effective if the reflector has mirror symmetry to a reflector mirror plane, wherein, in sectional representation perpendicular to the reflector mirror plane, the shape of a symmetrical half of the reflector is described by a conical section, wherein the reflector tapers to a point centrally in the direction toward the emitter tube.
A conical section is a section of the surface of a circular cone or double circular cone having a plane. Conical sections are, for example, ellipses, parabolas, or hyperbolas, and are defined by the equation y 2 =2Rx−(k+1)x 2 , where R is the curvature radius and k is the conical constant of the conical section. It has been shown that with such a reflector, in particular for an irradiation of a large irradiation area, a uniform irradiation distribution on the culture plane can be achieved.
It has proven favorable if at least one part of the surface of the emitter tube acts as a diffusor and diffusely scatters incident radiation.
A surface diffusely scattering incident radiation basically leads to a more uniform, non-directed radiation spreading. A diffusor therefore contributes to a uniform irradiation of the plants in the irradiation device. In a preferred embodiment, the entire surface of the emitter tube is constructed as a diffusor.
In this respect, the emitter tube preferably has a roughened surface acting as a diffusor having an average roughness Ra, wherein the average roughness Ra is in a range between 0.3 μm and 10 μm, preferably between 0.8 μm and 3 μm.
Roughened surfaces acts as diffusors, wherein their diffusor properties depend on the average roughness of the surface. The average roughness Ra is defined as the vertical measured value according to DIN EN ISO 4288:1988. Roughened surfaces having such a roughness exhibit nearly Lambertian scattering. The rate of backward scattering of the radiation incident on these surfaces is between 0% and 6%. A surface having an average roughness of less than 0.3 μm has a large component of backward scattered radiation.
It has proven favorable if the irradiation device comprises a housing having side walls, wherein a reflector foil, for example made of aluminum, is applied to at least one of the side walls.
A reflective inner lining by a reflector foil applied to the side walls of the irradiation device primarily reduces irradiation losses and can contribute to a uniform distribution of the irradiation intensity in relation to the culture plane. An especially symmetric, homogeneous radiation distribution is obtained if a reflector foil is applied to two opposing side walls or to all four side walls.
With the use of a reflective inner lining, infrared irradiation modules can be used in particular whose reflector is shaped such that a part of the radiation is emitted downwards in a flat angle relative to the horizontal into areas farther away from the irradiation module, which contributes to an overlapping of the irradiation areas, even with modules arranged in parallel and going beyond the closest neighbors, and a uniform distribution of the irradiation intensity in relation to the culture plane.
If no reflective inner lining is used, irradiation modules can be used in particular whose reflector is shaped such that the predominant part of the radiation is emitted into areas below the irradiation module, so that an overlapping of the irradiation areas is given mainly with the closest neighbor module arranged parallel thereto.
With respect to the emitter module, the object mentioned above is achieved according to the invention, starting from an emitter module of the generic type described at the outset, such that the infrared emitter has a cylindrical emitter tube having an emitter tube longitudinal axis, an emitter tube length of 50 mm to 500 mm, preferably 150 mm to 350 mm, and a heating filament arranged therein and designed for a temperature from 800° C. to 1800° C., wherein a reflector is allocated to one side of the emitter tube.
The emitter module is provided for use in an irradiation device according to the invention. With respect to this irradiation device, refer to the explanations above.
The emitter module is designed for the irradiation of plants. In particular, infrared emitters having a cylindrical emitter tube having an emitter tube length from 50 mm to 500 mm, preferably 150 mm to 350 mm, have a good size ratio, with which good results with respect to uniform irradiation intensity are achieved on the culture plane. They are suitable for achieving an average irradiation intensity on the culture plane from 10 W/m 2 to 100 W/m 2 .
It has also been shown that an optimum plant growth is achieved if the heating filament is designed for a temperature from 800° C. to 1800° C. Emitters that have a filament temperature in the range stated above at the nominal voltage emit radiation having an intensity maximum at wavelengths in a range between 0.7 μm and 3.5 μm. The emitted radiation is therefore available for irradiating both the upper and also lower leaf layers.
Suitable modifications to the irradiation device according to the invention arise from the above explanations.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
The foregoing summary, as well as the following detailed description of the invention, will be better understood when read in conjunction with the appended drawings. For the purpose of illustrating the invention, there are shown in the drawings embodiments which are presently preferred. It should be understood, however, that the invention is not limited to the precise arrangements and instrumentalities shown. In the drawings:
FIG. 1 is a first embodiment of the irradiation device having an emitter zone according to the invention for irradiating plants,
FIG. 2 is a ray-tracing simulation of the irradiation intensity for a second embodiment of the irradiation device according to the invention,
FIG. 3 is an embodiment of an emitter module according to the invention for use in an irradiation device according to the invention,
FIG. 4 is a side view of another emitter module according to the invention for use in an irradiation device according to the invention,
FIG. 5 is a cross section of another embodiment of the emitter module according to the invention having an infrared emitter, with two reflector strips being mounted on the emitter tube of this infrared emitter for reducing the irradiation emission in an angular range, and
FIG. 6 in cross section, another embodiment of the emitter module according to the invention for use in an irradiation device according to the invention having two additional reflectors laterally of the emitter tube, and
FIG. 7 in cross section, another embodiment of the emitter module according to the invention for use in an irradiation device according to the invention having a reflector in which two side wings are connected to the reflector.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 shows an irradiation device for irradiating plants, which is designated overall with reference number 1 . The irradiation device 1 is provided for tiered crop growing and comprises a housing 15 having five plant modules (tiers) arranged one above the other for the cultivation of plants, of which only two plant modules 10 , 20 are shown in FIG. 1 for the purpose of simplification. The plant modules that are not shown have identical constructions to the plant modules 10 , 20 . A reflector film 18 a , 18 b is applied on both side walls 16 , 17 of the housing.
The plant modules 10 , 20 comprise a carrier element 2 and an installation space B arranged above the carrier element 2 and having electrical cables and mounting elements, as well as the emitter zone Z arranged under the installation space. The carrier element 2 is filled with dirt and planted with several plants 3 . The surface of the planted carrier element defines a culture plane E. The emitter zone Z is located above the culture plane E. In the emitter zone Z there are LED strips 4 a , 4 b , 4 c that emit essentially visual radiation 5 having wavelengths in the visible and ultraviolet range. In the emitter zone Z there are also several emitter modules 7 for irradiating the plants with infrared radiation 6 .
The emitter modules 7 have an infrared emitter 8 , wherein an irradiation area F on the culture plane is allocated to each infrared emitter 8 , wherein this area is indicated by dotted lines 6 that symbolize the infrared irradiation.
The infrared emitters 8 are each designed for a nominal power of 100 W for a nominal voltage of 115 V. They have a cylindrical emitter tube made of quartz glass having an outer diameter of 13.7 mm and an emitter tube length of 240 mm.
The side of the emitter tube facing the culture plane E has an average roughness of 3.5 μm; it acts as a diffusor. Within the emitter tube there is a heating element that is operated at a temperature of 900° C. at nominal power output.
On the side of the infrared emitter 8 facing away from the culture plane E there is a reflector 9 that reduces the spreading of infrared radiation emitted by each infrared emitter 8 upward in the direction of the installation space B and laterally in the direction of the LED strips 4 a , 4 b , 4 c.
The reflectors 9 each extend parallel to the infrared emitter 8 allocated to them and have a length of 390 mm and a width of 120 mm. The reflector 9 has a mirror-symmetric reflector base body, wherein the surface shape of one symmetry half is described in cross-sectional representation by a parabola. Two side wings 9 a , 9 b are connected to the reflector 9 . Both side wings 9 a , 9 b enclose, with the horizontal, an angle of 30°. The surface of the side of the reflector 9 facing the infrared emitter 8 and the side wings 9 a , 9 b is produced from hammered aluminum; it has a diffusely reflective effect.
In an alternative embodiment it is provided that, on a side area of the lateral surface of the emitter tube, a reflector strip that runs in the direction of the longitudinal axis and is made of gold is mounted, as well as another reflector strip in a mirror-symmetric arrangement. These reflector strips reduce emission of infrared radiation 6 in the direction of the installation space and the other radiation sources in the emitter zone. Each reflector strip covers a circular arc of the emitter tube cross section that encloses, with a horizontal running through the filament center, a coverage angle between −2° and +25°, wherein the smaller angle magnitude is to be allocated to the area underneath the horizontal.
In the direction of the longitudinal axes of the infrared emitters 8 there are several structurally identical emitter modules 7 arranged one behind the other (not shown). Adjacent infrared emitters 8 have, in the direction of their longitudinal axis, a spacing of 1.54 m from each other. The spacing of adjacent infrared emitters arranged parallel to each other perpendicular to the direction of their longitudinal axes is 1.65 m. The infrared emitters have a spacing of 1.0 m from the culture plane E.
The infrared emitters 8 are arranged in the emitter zone Z relative to each other such that their emitter tube longitudinal axes run parallel to each other; they are arranged one next to the other in the sense that they begin and end at the same longitudinal position of the illumination field. The number of infrared emitters in relation to the area of the culture plane is 0.4 m −2 . In addition, the infrared emitters 8 are arranged in the emitter zone Z so that their irradiation areas F overlap laterally, such that the average irradiation intensity on the culture plane is 30 W/m 2 .
FIG. 2 shows a ray-tracing simulation of the irradiation intensity with infrared radiation of a second embodiment according to the invention of the irradiation device 200 for irradiating plants. In FIG. 2 the irradiation intensity on the plant plane at a spacing of 1 m from the infrared emitters is given in W/mm 2 .
The irradiation device 200 used for the ray-tracing simulation has four plant tables 201 , 202 , 203 , 204 arranged one next to the other, which together define the culture plane of the irradiation device. Each of the plant tables 201 , 202 , 203 , 204 has a length of 6 m and a width of 1.65 m. Above each plant table 201 , 202 , 203 , 204 there are five emitter modules 205 in an emitter zone Z each having an infrared emitter. In relation to the culture plane, the number of infrared emitters is approximately 0.5 m −2 . The nominal power output of the infrared emitter (for a nominal voltage of 115 V) is 96 W. The infrared emitter is distinguished by an emitter tube length of 260 mm, an emitter tube outer diameter of 10 mm, and by a heating filament arranged within the emitter tube. The spacing of the infrared emitter from the culture plane is 1.0 m. A reflector according to FIG. 3 is allocated to the side of the emitter tube facing away from the culture plane E. At the same height of the emitter zone Z there are multiple LED strips (not shown) for the emission of radiation in the ultraviolet and visible range. To ensure a homogeneous irradiation intensity, a reflective inner lining 206 , 207 is provided on each of the two side walls of the irradiation device 200 .
The diagram 209 also shows—viewed in the longitudinal direction of the plant table 202 —the profile of the irradiation intensity in W/mm 2 along a center axis 208 of the plant table 202 . The diagram 211 shows the profile of the irradiation intensity along a center axis 210 of the irradiation device 202 . The average irradiation intensity on the entire culture plane E is 27 W/m 2 with a minimum irradiation intensity of 20 W/m 2 and a maximum irradiation intensity of 32 W/m 2 .
In FIG. 3 an embodiment of an emitter module 300 for irradiating plants with infrared radiation is shown for use in an irradiation device according to the invention. The emitter module 300 comprises an infrared emitter 301 having an emitter longitudinal axis 305 and a reflector 302 .
The infrared emitter 301 has a cylindrical emitter tube 303 made of quartz glass and a heating filament 304 arranged within the emitter tube 303 . The infrared emitter is distinguished by an emitter tube length of 270 mm and by an outer diameter of 10 mm. The heating filament 304 is made of tungsten wire. The length of the heating filament 304 is 240 mm. The nominal power output of the emitter is 96 W at a nominal voltage of 115 V.
The reflector 302 has a length of 350 mm in the direction of the emitter longitudinal axis 305 , and perpendicular thereto a width of 94 mm. The reflector 302 has a mirror-symmetric construction. The reflector surface of one mirror half has a curvature whose profile can be described by a conical section having the equation y 2 =2Rx−(k+1)x 2 . (The conical section constant k equals −1; the radius of curvature R equals 132 mm. The spacing B of the reflector to the center axis of the emitter tube 303 equals 7.5 mm.)
FIG. 4 shows an embodiment of an emitter module 400 according to the invention in a side view. Insofar as the same reference symbols in FIGS. 4 to 6 are used as in FIG. 3 , these designate structurally identical or equivalent components and parts, as explained in more detail above with reference to the description of the embodiment according to FIG. 3 of the lamp unit according to the invention.
The emitter module 400 comprises an infrared emitter 301 having an emitter tube 303 and a heating filament 304 arranged therein, as well as a reflector 302 . The length A of the heating filament 304 is 240 mm. The emitter tube 303 has a roughened surface having an average roughness Ra of 3.5 μm.
FIG. 5 shows a cross section of an emitter module 500 according to the invention having an infrared emitter 501 , on whose emitter tube two reflector strips 503 a , 503 b are also mounted.
The infrared emitter 501 has a cylindrical emitter tube 503 made of quartz glass and a heating filament (not shown) arranged within the emitter tube 503 . The nominal power output of the infrared emitter (for a nominal voltage of 115 V) is 96 W. It is distinguished by an emitter tube length of 260 mm and by an outer diameter of 10 mm. On the emitter tube 503 there are two reflector strips in the form of a gold coating that extends in the direction of the emitter tube longitudinal axis. The width of the reflector strip 503 b is designed so that it covers a circular arc described by an angular area α between −5° and +22°, starting from a horizontal axis 510 to which the angle 0° is assigned. The reflector strip 503 a is arranged mirror-symmetric to the reflector strip 503 b ; it covers a circular arc having an angular area α between 158° and 185°. The two reflector strips 503 a , 503 b reduce the emission of infrared radiation upward in the direction of the installation space and to the side in the direction of the UV/VIS radiation sources in the emitter zone, whereby this ensures, for example, a longer service life of the radiation sources arranged there.
FIG. 6 shows a cross section of an emitter module 600 according to the invention having an infrared emitter 601 having two additional reflectors 603 a , 603 b arranged laterally of the emitter tube.
The infrared emitter has a cylindrical emitter tube made of quartz glass and a heating filament 604 arranged on the bottom of the emitter tube. The nominal output power of the infrared emitter (for a nominal voltage of 115 V) is 96 W. It is distinguished by an emitter tube length of 260 mm and by an outer diameter of 10 mm. The two lateral reflectors 603 a , 603 b are arranged such that they cover, with a horizontal through the center of the filament, an angle α of 28° above the horizontal and thus minimize the emission upward into the angular area not covered by the upper reflector 602 . The angle of the lateral reflectors 603 a , 603 b relative to the horizontal is 55°, the spacing of the lateral reflectors 603 a , 603 b from the emitter tube is, at the shortest point, 3 mm. The spacing from the center axis of the emitter tube to the upper reflector 602 , whose outer dimensions are 120×390 mm 2 , is 15 mm. The shape of the upper reflector is described by a parabolic conical section having a radius of curvature of 115 mm.
In FIG. 7 another embodiment of an emitter module 700 according to the invention is shown in cross section for use in an irradiation device according to the invention. The emitter module 700 comprises an infrared emitter 301 and a reflector 702 , wherein two reflective side wings 703 a , 703 b are connected to the reflector 702 . The two side wings 703 a , 703 b are arranged such that they enclose an angle of 30° with a horizontal. They have a width C of 84 mm. The width D of the reflector is 88 mm. Both the side wings 703 a , 703 b and also the reflector 702 have a length of 338 mm. The arrangement of the side wings 703 a , 703 b reduces the emission of infrared radiation upward in the direction of the installation space and laterally in the direction of the UV/VIS radiation sources in the emitter zone.
It will be appreciated by those skilled in the art that changes could be made to the embodiments described above without departing from the broad inventive concept thereof. It is understood, therefore, that this invention is not limited to the particular embodiments disclosed, but it is intended to cover modifications within the spirit and scope of the present invention as defined by the appended claims. | A device is provided which ensures uniform irradiation of plants with infrared radiation along with ultraviolet and/or visible radiation and requires a small number of infrared emitters relative to the cultivation area. The infrared emitters are designed for temperatures of 800° C. to 1800° C. Each has a cylindrical emitter tube having a length of 50 mm to 500 mm. The emitter tubes extend parallel to one another in an emitter zone located above the culture plane. The infrared emitter occupation density relative to the area of the culture plane is between 0.2 m −2 and 1.0 m −2 . Irradiation regions of adjacent infrared emitters on the culture plane overlap such that average irradiance on the culture plane is between 10 watt/m 2 and 100 watt/m 2 with a variation range of a maximum of 50%. A reflector facing a structural space is assigned to a top side of the emitter tube. | 8 |
BACKGROUND OF THE INVENTION
This invention relates generally to towel dispensers, and more particularly to a dispenser for both wet and dry towels.
DESCRIPTION OF THE PRIOR ART
For many years, disposable towels, usually made of paper or derived from paper products, stored and dispensed from wall-mounted dispensers, have been commonplace in public restrooms and other facilities. As a result of the increasing attention given in recent years in connection with efforts to protect from nosocomial infections, the essential impracticality of conventional paper towel or fabric roll towel dispensing is realized. It is desirable that hands be washed and, in some applications, an antiseptic supplied. Hot water is not always available, nor is a soap or hand washing liquid, nor is there assurance that such cleaners would have proper antiseptic properties.
Efforts have been made to provide suitable dispensers for dispensing wet and dry towels. An example is the U.S. Pat. No. 3,388,953 issued to Browning on June 18, 1968. FIG. 2 of that patent shows an arrangement where, with the handle 48 in the upward position 49, dry towels 15 can be dispensed. With the handle 48 in the downward position 50, the wetting belt 20 is engaged by the towel 15 as the belt forces the toweling against the counter pressure surface of roller 37, to wet the towel being dispensed. An earlier U.S. Pat. No. 3,084,664 issued to Perlman et al. on Apr. 9, 1963 discloses an arrangement where, with the button 73 pushed, dry toilet paper is dispensed, but with the button 72 pushed, the toilet paper web 26 is pressed upon the upper surface of the wetting roller 59 to dispense wet toilet paper.
Other patents which disclose wet towels include U.S. Pat. No. 3,025,829 issued to Smith on Mar. 20, 1962, U.S. Pat. No. 3,368,522 issued to Cordis on Feb. 13, 1968 and showing several ways of wetting roll toweling and also stacked sheet toweling, and U.S. Pat. No. 4,620,502 issued to Kimble on Nov. 4, 1986 and showing a belt means for dispensing wet toweling from a roll.
There is a U.S. Pat. No. 4,747,365 issued to Tusch on May 31, 1988 and showing a system for dispensing dry or wet toilet paper from a dispenser. By pushing down handle 13, the guide roll 9 forces the paper from roll 3 against a pick-up roller which applied medicament to the paper from the reservoir 4. FIGS. 4 and 5 show two different arrangements of roller parts 22a and 22b in FIG. 4, or 22c in FIG. 5 as alternative arrangements of pick-up roller and which do not wet the entire width of the paper so as to leave part of it dry enough not to destroy its strength and thereby preclude withdrawal from the dispenser. The Smith U.S. Pat. No. 3,025,829 uses spaced sponge sleeves 31 to avoid wetting the central portion of the paper as it passes over the pick-up roller 29 and thereby avoid weakening the paper which might otherwise tear at the point between the pressure roller and pick-up roller.
It is evident from several of the foregoing patents, particularly the Smith patent and the Tusch patent, that there is a problem dispensing wet paper due to the loss of strength when it is wetted. Those patents attempted to deal with the problem by wetting only a part of the width of the sheet. Also, for the paper to have suitable hand-cleaning qualities, it will tend to use excessive amounts of liquid while being wetted in the dispenser. This results in expense of liquid, extra maintenance of the liquid reservoir, or additional space requirement to store additional volumes of the liquid. Thus, there has remained a need for a better wet/dry towel dispenser. The present invention addresses this need.
SUMMARY OF THE INVENTION
Described briefly, according to a typical embodiment of the present invention, a towel dispenser includes two supplies of toweling material in dry roll form. Both supplies are dry. A dispenser initiating system includes a push-operated member for initially dispensing short lengths of toweling from both rolls to a dispensing position. This operation also initiates wetting of the toweling dispensed from one of the rolls. It also releases the system to enable the user to pull an additional predetermined length of toweling from each of the two rolls. The length from one is suitably dampened as the toweling is pulled, while the length from the other roll is dry. As the wet towel is pulled, the dry towel is automatically dispensed at the same time. They are used in sequence, the wet towel first and the dry towel next. Any suitable wetting agent, including water, detergent, soap, antiseptic and/or other media to be applied to the wet towel, can be used. The towels in the two supplies differ in absorbency, texture and other physical and chemical characteristics, as desired.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a pictorial view of a towel dispenser according to a typical embodiment of the present invention.
FIG. 2 is a front elevational view thereof but with the housing front omitted to show interior details.
FIG. 3 is a side sectional view of the dispenser taken at the line 3--3 in FIG. 2 and viewed in the direction of the arrows but omitting the roller side frame.
FIG. 4 is a diagram (viewed axially) of the three control cams mounted to a shaft, but omitting the sprocket.
FIG. 5 is an enlarged top view of the wetting roller (with a portion broken out to conserve space) and mounting yoke for it.
FIG. 6 is a side view of the wetting roller mounting bracket support arm.
FIG. 7 is an enlarged side view of a lower portion of a side frame with towel clamping unit (shown partially in section) and actuator linkage for it.
FIG. 8 is a fragmentary view from the rear of a portion of the side frame with clamping unit and support as at line 8--8 and on the same scale as in FIG. 7 but with link 114 turned up to the clamp release position as in the dotted lines of FIG. 7.
DESCRIPTION OF THE PREFERRED EMBODIMENT
For the purposes of promoting an understanding of the principles of the invention, reference will now be made to the embodiment illustrated in the drawings and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended, such alterations and further modifications in the illustrated device, and such further applications of the principles of the invention as illustrated therein being contemplated as would normally occur to one skilled in the art to which the invention relates.
Referring now to the drawings in detail, the dispenser includes a back plate 11 mounted to the building wall 12. The housing includes side walls 13R and 13L projecting forward from the back plate, and a lower front wall 14 extending across the front. A cover 16 is hinged to the top of wall 14 at 17 and latched at the top at 18 to the back wall whereby the cover can be swung out from the back plate in the direction of arrow 19 (FIG. 3). The cover extends to back plate 11 at the top and the left side above the level of the hinge 17 to facilitate installation of toweling.
A roll 21 of drying towel material is placed in the housing for rotation about a shaft 22 to deliver a web 23 of drying towel material down through the housing. A roll 24 of cleaning towel material is placed in the housing for rotation about a shaft 26 to deliver a web 27 of cleaning towel material down through the housing. Alternatively, both of these rolls may be provided in a single removable cartridge sitting in a cradle (not shown) in the housing. In that case too, the rotational axes of the towels would be in the same location, as the axes of shafts 22 and 26. In any case, the materials in both rolls of material is dry. That delivered from one roll is subsequently wetted to enhance its cleaning ability, so it may be referred to hereinafter as "cleaning" towel or "wet" towel or "washing" towel.
A drying towel feed roller 31 is secured on shaft 32 rotatably mounted on two horizontally-spaced roller support side frames 37 (shown in FIG. 2 but not in FIG. 3) fastened to back plate 11 in the housing. A drying towel pinch roller 33 is rotatably mounted on a shaft 34 which is non-rotatably supported at its ends in elongated slots 36 (FIG. 7) in the roller support side frames. The shaft 34 (FIG. 3) is normally urged forward in the slot 36 at each end of the shaft by a spring 38 mounted on a guide pin 39. The pin 39 is actually a screw passing through a transverse hole in the shaft 34 and threaded into a combination pin mount and spring seat 41 pivotally mounted at pin 42 which is eccentrically mounted to the end of cam shaft 43 mounted in apertures 44 in side frames 37. One end of each spring 38 seats on shaft 34. The other end seats on seat 41. Shaft 43 is normally indexed to a rotational position where eccentric pin 42 is located as shown in the solid lines in FIG. 3 whereupon springs 38 urge the pinch roller forward against the web 23 urging it against the drive roller 31. Shaft 43 can be manually turned 180° in holes 44 to a pinch roller release orientation where eccentric pins 42 are in the dotted line position 46 in FIG. 3. As this occurs, the heads of screws 39 engage and pull shaft 43 rearward causing the pinch roller to separate from the towel web 23 and drive roller 31 to permit freely feeding the web 23 down through it. This is useful for loading the dispenser.
A towel cut-off knife 47 fastened by suitable brackets (not shown) to side frames 37 has the cut-off edge 48 located at a drying towel dispensing station where the strip 23S of drying towel extending below the edge 48 can be torn off by pulling it forward in the direction of arrow 49.
A washing towel drive roller 51 is secured on shaft 52 rotatably mounted in holes 52a in the roller support side frames 37. A sprocket 53 on the outer end of the shaft is coupled by a chain 54 to the sprocket 35 which is at the outer end of shaft 32. This chain goes around sprocket 56 which is rotatably mounted to cam shaft 57 which is mounted between the roller support side frame 37 and the actuating mechanism side frame 58 which is fastened to back plate 11. While sprockets and chain are mentioned here, gear-belt or other synchronized drive systems may also be used.
Three cams and sprocket 56 are rotatably mounted to the shaft 57. They are non-rotatably fastened to each other by a spring-type connector and indexing pin 60 ("Rollpin", for example). One of these cams, a towel advance cam 59, is a cylindrical disc having a pawl receiving notch 61 on its exterior cylindrical surface 62. Only half of the cam 59 is shown in FIG. 3, so another cam (the release cam) can be seen behind it. Notch 61 is formed to provide a pawl stop 63 engageable by the hooked distal end 66a of pawl 66 when the pawl is moved in the direction of arrow 67. The proximal end of the pawl is received in a downwardly opening slot in, and pivotally mounted at 68 to, a linear cam drive body 69 fastened by block 70 to rods 71 connected to the advance push pad 72. The rods 71 are slidable in guide brackets 73 fixed in between the side frames 37 and 58. The push pad, rods and linear cam are all normally held in a position shown in FIG. 3 by the spring 74 which has its front end hooked to the front bracket and its rear end hooked to the block 70.
Linear cam drive body 69 has a cam ramp 76 on the upper surface thereof. A cam follower roller 77 is received on the upper surface immediately behind this ramp. This roller is a ball bearing assembly whose inner race is fixed on a shaft 77s secured to the top corner portion of a generally triangular release latch or "indexing lever" 78 which is pivotally mounted to shaft 79 connected between the side frames 37 and 58. A "release cam" 80 is one of the three cams mounted to shaft 57. It is a cylindrical disc having a single detent notch 81 in its outer cylindrical surface. The release latch 78 has a lug 82 at its lower front end received in the detent notch 81 in the outer cylindrical surface of release cam 80.
A "wetting cam 83" (not shown in FIG. 3) is also mounted on shaft 57 with the other two cams. It is a circular disc with a cam groove 84 (FIGS. 4 and 5) on the inside face thereof in which a follower roller 85 is received. This follower roller 85 is rotatably mounted at the end of a shaft 85S which is rotatably received in bearings in the opposite ends of a tube 86. This tube has a pair of support arms 87 fixed to it near its ends. A wetting roller 88 is rotatably mounted on tube 86. The support arms 87 have horizontally extending slots 89 (FIG. 6) received on spacer bushing 90 fastened to the side frames 37 by screws 91 and nuts 91a threaded thereon (FIG. 5).
A pinch roller 92 is mounted between the rollers 51 and 88, and its shaft 93 is received in slots 94 (FIG. 7) in side frames 37. The pinch roller is urged toward the drive roller 51 by wetting roller 88. This is achieved by the slotted arm and spring loaded mounting arrangement for the wetting roller. Each end of tube 86 has a circumferential groove thereon as does each of the bushings 90. These grooves receive spring anchor rings 95 therein, which are simply snapped over the ends and received in the grooves and have loops as at 95a to which the ends of the tension coil springs 95 are hooked. The slots in arms 87 permit springs 96 to pull the wetting roller snugly against the washing toweling web 27 sandwiched between the wetting roller and pinch roller 92. The slots 94 in side frames 37 permit the pinch roller to be pushed snugly against the web 27 between the pinch roller and the drive roller 51.
The arm 87 mounting arrangement on bushings 90 permits pivoting the wetting roller up and forward from the position shown by the solid outline to the dotted outline position 88a to permit threading the washing towel web 27 into the machine when loading the new toweling in it. To swing the wetting roller up, the shaft 85S must be shifted in the direction of arrow 85A (FIG. 5) to get the cam follower roller 85 out of cam groove 84. To shift the shaft, the shaft locating lever 85L is manually raised out of the locating notch 37N in the locating bracket 37B on side frame 37, and the shaft is shifted in the direction of arrow 85A. Then the wetting roller can be swung up to the dotted line position in FIG. 3 for installing the new washing towel web. The cutouts 40 (FIG. 7) in roller side frames 37 accommodate the upward and forward pivoting of the support arms 87. With the wetting roller in the position shown in solid lines in FIG. 3, it is slightly submerged into the reservoir of wetting agent 97 in tray 98 which is secured in the housing. In this position, the web 27 follows a serpentine path under the wetting roller, up between the wetting roller and pinch roller, over the pinch roller and down between the pinch roller and drive roller 51 and out past the cutting edge 99 of the fixed tear-off knife 100 to expose the web end strip 27s below edge 99.
The release latch 78 is normally held downward in the direction of arrow 101 by the return spring 102, whose lower end is based on post portion 103 (FIG. 2) of latch body 78. The post portion projects inwardly from latch 78. A pin (not shown) projecting upward from post 103 inside the spring 102 retains the spring in position on the post. The upper end of spring 102 is seated in a socket in bracket 104 secured to the right-hand roller side frame 37.
A clamp unit 105 (FIGS. 3, 7 and 8) is operated in synchronism with the latch 78. To facilitate showing other features, the clamp unit is not shown in FIG. 2. The clamp unit is actually a rectangular frame having parallel front and rear clamp bars 111 and 112 fixed to parallel side plates 105S located just outboard of the roller side frames 37. A bottom plate 105B is secured to bar 111 and side plates 105S and extends downward and rearward to the down curved rear edge 105E located below and ahead of rear cutting edge 48. The clamp unit has front and rear horizontally extending support pins 106 and 107 in bars 111 and 112 and received in identical slots 108 and 109, respectively, of the right side frame 37. Identical pins are received in identical slots in left side frame 37 so the bar is slidable upward from a release position to the applied position of FIG. 7 where clamp faces 111F and 112F of the front 111 and rear 112 clamp bars, respectively, clamp the towel webs 27 and 23 against the knife edges 99 and 48, respectively.
To push the clamp bars upwardly to the clamping position shown in FIGS. 3 and 7, links 113 and 114 similar to roller chain links are provided outboard of the side frames 37 at the left and right sides of the dispenser. Link 113 has its lower end secured to shaft 116 which extends through right side frame 37, across to left side frame 37 and through it to its counterpart link 113L. The upper end of link 113 is pinned at 115 to the lower end of link 114. The upper end of link 114 is pinned to the clamp bar 111 at the clamp bar front support pin 106 which is slidable in slot 108 in side frame 37. In this context, the references to "upper" and "lower" ends of link 114 should be understood to refer to that link when in the bar clamping position of FIG. 7, not when the link is in the alternate, bar-release, position shown in FIG. 8 and in dotted lines in FIG. 7.
At the right side of the dispenser, the pin 115 which connects links 113 and 114 pivotally receives the lower end bearing block 117 of the push rod 118. This is shown in FIGS. 2, 7 and 8, but link 113 is omitted from FIG. 8 to facilitate illustration of the other features. An upper end bearing block 119 is threaded onto the upper end of push rod 118. Block 119 is pivotally mounted on pin 121 (FIG. 2) at the inner end of post 103. Rod 118 is screwed into block 119 to permit adjustment of the clamping force of the clamp bars. Also, the cut-off knives 47 and 100 are adjustable on initial assembly to the side frames 37, or later, if desired, to further adjust clamping force. This is accomplished by providing oversized holes in the side frames 37, for the cut-off knife mounting screws.
The tray 98 is supplied by a wetting agent from trough 122 mounted in the housing and having a circular upper edge ring 123 supporting a container 124 (preferably a two quart size) which is inverted in the housing and has a circular outlet rim 126 defining the level of the liquid in the tray. A diaphragm piercing point 127 is in the bottom of the trough 122 under the center of the liquid container. Therefore, when the container is inserted in the vertical direction and the point 127 pierces the diaphragm or seal 128 in the bottom of the container, liquid therefrom can fill the trough to the level of the rim 126 around the outlet opening. This level is high enough to contact the web 27 as it is fed from the roll around the rollers and out from the dispensing locations.
In operation, upon pushing the pad 72 to the right, advance pawl hook 66a will engage the stop 63 and rotate the cam and sprocket pack 59-56 sufficiently that the chain 54 around the sprockets connected to the two drive rolls 31 and 51 will pull approximately one inch of paper from both towels to expose approximately one inch of paper below the knife edges. The space between the hook 66a at the end of the advance pawl and the stop 63 at the end of the advance cam 59 is such that there is approximately .25 inches of lost motion of the push pad before rotation of the advance cam is commenced. During this first .25 inches of travel, the ramp 76 on the drive block 69 pushes the release latch up so the detent lug 82 thereof is out of the notch 81 in the release cam 80, enabling the cam to turn. This action also pulls rod 118 upward which pulls the joint between links 113 and 114 upward to the dotted line position in FIG. 7, to release the clamp bars. During the last 1.0 inches of travel of the approximate 1.25 inches total travel of the advance push pad 72, approximately one inch of both towels will become exposed below the lower cutting edges of the knives for the respective towels. Due to the configuration of the wetting cam groove (FIG. 4), the first and last inch of washing towel will be dry. Therefore, the exposed portion of the washing towel will be dry. Then that edge of the washing towel is manually pulled downward, and approximately ten inches more of the towel can be pulled out before the release latch lug 82 again enters the notch 81 of the release cam to stop rotation of it. When that happens, the clamping bars operated by the link 118 between the release latch 78 and the clamping unit will cause the clamping bars to close. The last one inch of the washing towel will be dry because of the wetting roller cam track 84 which lifts the wetting roller out of the wetting agent in the tray to the position shown by dotted line 88b (FIG. 3) during the last 1.0 inch of travel as the toweling is pulled out.
The drying towel is automatically dispensed at the same time the washing towel is pulled out, because of the chain drive from the sprocket at the end of the washing towel feed drive roller also driving the drying towel feed roller. After the release latch has stopped rotation of the release cam, and thereby the advance cam, the pawl will have fallen into the large notch 61 in position ready for the next push of the push pad 72. The washing towel can be torn off to wash the hands. Then the drying towel can be torn off to dry the hands. This procedure is repeated for every towel combination desired.
Any kind of suitable cleaning agent, liquid soap, antiseptic or a two-part type such as "Alcide" can be employed in the liquid container and therefrom to the wetting tray. The washing towel and drying towel materials are different. The washing towel is not as absorbent. Therefore, it does not accumulate large amounts of the wetting agent, nor does it use too much of the wetting agent in too short a time. Even though it is wetted in the tray and is referred to as the "wet" towel, it is not dispensed dripping wet, and the contour of the cam track 84 raises the wetting roller soon enough to enable the non-dipped portions to absorb any extra wetting agents that may be pinched out and accumulate above the drive roller 51. On the other hand, the drying towel is a more absorbent type of towel which has a more luxurious look and feel to it. It may also contain a skin emollient ("moisturizer") to soften the hands. The nature of the materials is such that the drying towel is more absorbent, not only because of greater thickness, but also because of greater absorbency per square inch of web area. Thus, it is more absorbent not only per square inch of web area, but also per cubic inch of material volume. The wet and dry towels can be color coded. An indicator flag or other device can be provided in a window on the dispenser, if desired, to alert service or maintenance people when there is a need to replenish towels.
The present invention should be very beneficial in restaurants, laboratories, hospitals, nursing homes, retirement homes, child day care centers, restrooms, and all other locations where the cleaning and sanitizing of hands is desirable. Thus, with the present invention it is possible to be assured that there is ample opportunity for anyone to cleanse their hands upon entering or before leaving a room where infectious agents may have been handled. The arrangement of the slide block 70 and attendant parts lends itself to operation by a powered linear actuator such as a pneumatic cylinder or solenoid, either of which might be pedal-switch actuated, sound or voice switch actuated or otherwise remotely actuated to obviate the touching of a hand-operated push pad to initiate the dispensing function.
While the invention has been illustrated and described in detail in the drawings and foregoing description, the same is to be considered as illustrative and not restrictive in character, it being understood that only the preferred embodiment has been shown and described and that all changes and modifications that come within the spirit of the invention are desired to be protected. | A towel dispenser contains two rolls of paper. A bar on the front, when pushed, delivers a short length of wet towel and a short length of dry towel, simultaneously. It also guides the towel dispensed from one of the rolls through a bath of antiseptic hand-cleansing solution. It also releases the system to enable pulling an additional length of toweling from each of the two rolls. Upon release, either towel can be pulled out further manually to produce about ten more inches of towel. The toweling is delivered from both rolls simultaneously, but the towels are used in sequence, the wet towel first and the dry towel next. | 8 |
This application is the U.S. national phase of international application PCT/IT2003/000626 filed 14 Oct. 2003 which designated the U.S. and claims priority of IT RM2002A000562, dated 6 Nov. 2002, the entire contents of each of which are hereby incorporated by reference.
The invention described herein relates to the use of resveratrol as an active ingredient in the preperation of a medicament for treating influenza virus infections.
BACKGROUND OF THE INVENTION
Resveratrol, i.e, 3,4,5-trihydroxystilbene, has been intensively studied recently, in relation to the known beneficial properties of red wine, of which it is one of the fundamental ingredients ( Life Sci., 71, 2145-52, 2002).
Resveratrol is located in the skins of black grapes in amounts ranging from 50 to 100 μg/gram and its concentration in red wine ranges from 1.5 to 3 mg/l.
Numerous studies have demonstrated an anticarcinogenic activity of resveratrol, the mechanisms of action of which can be subdivided as follows: inhibition of activation of transcription factor NF-kB, capable of regulating the expression of various genes involved in inflammatory and carcinogenic processes ( Lancet, 341, 1103-1104, 1993; Science, 275, 218-220, 1997; Proc. Natl. Acad. Sc., 94, 14138-14143, 1997; Life Science, 61, 2103-2110, 1997; Brit. J. Pharin., 126, 673-680, 1999; J. Imm., 164, 6509-6519, 2000); inhibition of various proteins, including protein kinase C ( Bioch., 38, 13244-13251, 1999), ribonucleotide reductase ( FEBS Lett., 421, 277-279, 1998) and cyclo-oxygenase-2 (COX-2) in mammalian epithelial cells ( Ann. N.Y. Acad. Sci, 889, 214-223, 1999; Carcinog., 21, 959-963, 2000); activation of caspases 2, 3, 6 and 9 ( FASEB J., 1613-1615, 2000) and modulation of the gene p53, which is a known tumour suppressor ( Cancer Research, 59, 5892-5895, 1999; Clin. Bioch., 34, 415-420, 2001).
Among the beneficial actions of resveratrol we should also mention its antioxidant activity, suggested by the above-mentioned ability to counteract the damaging effects produced by various substances and/or conditions that cause intracellular oxidative stress ( Free Radic. Res., 33, 105-114, 2000).
Resveratrol can induce vascular relaxation by means of production of nitric oxide at the vascular endothelial level ( Cancer Res., 59, 2596-01, 1999), inhibit the synthesis of thromboxane in platelets ( Clin. Chim. Acta, 235, 207-219, 1995; Int. J. Tissue React., 17, 1-3, 1995), and of leukotrienes in neutrophils and prevent the oxidation and aggregation of low-density lipoproteins (LDL) ( Lancet, 341, 1103-1104, 1993; Life Sci., 64, 2511-2521, 1999).
Recently, an inhibitory activity of resveratrol against the Herpes Simplex DNA virus has been demonstrated ( Antiv. Res., 43, 145-155, 1999) on the basis of in-viutro experimental systems.
Data obtained by the present authors and by other research teams have revealed that many antioxidant substances are capable of inhibiting the replication of the parainfluenza Sendai virus (SV) type 1, of the Herpes Simplex 1 virus (HSV-1) and of the acquired immunodeficiency virus (HIV) in vitro ( AIDS Res. Hum. Retoviruses, 1997: 1537-1541; Biochem. Biophys. Res. Communt., 1992; 188, 1090-1096; Antivir. Res., 1995, 27, 237.253). The antiviral efficacy of antioxidant substances has also been demonstrated in a murine AIDS (MAIDS) model, as well as in HSV1 keratitis ( AIDS Res. Hum. Retroviruses, 1996: 12, 1373-1381: Exp. Eye. Res., 200: 70, 215-220).
Influenza is an epidemiological problem of worldwide proportions with serious public health problems as a result and with major health-care economic repercussions. The virus responsible for influenza is widespread and highly infectious. Unfortunately, the therapies currently available are still not fully effective and often lead to the selection of resistant viral strains ( Fields, cap 47, 1533-79, 2001) and, what is more, the vaccination campaigns, in addition to the disadvantages inherent in vaccine-based prevention, do not as yet provide satisfactory cover owing to the extreme antigenic variability of the virus ( Fields, cap 47, 1533-79, 2001).
Among the various strategies for attacking viral replication, recent studies ( J. of Virol., 74, 1781-1786, 2000) have reported the important role of protein M1 in the transportation of specific virus ribonucleoproteins to the cytoplasm. This appears to be a fundamental stage in the replication cycle of the virus, so much so that inhibition of viral replication can be pursued through retention of the nucleoprotein in the nucleus of the infected cell due to the inhibited synthesis of protein M. This phenomenon may be attributable to inhibition of cell proteins with a kinase function. In fact, it has recently been demonstrated that inhibition of the kinases causes retention of the NP of the cell nucleus ( Nature Cell. Biol., 3, 301-5, 2001; J. of Virol., 74, 1781-86, 2000), together with a potent inhibitory action against replication of the influenza virus.
GSH is known to be the main antioxidant in the cellular redox system and has been associated with the replication of various viruses. In fact, previous studies conducted by the present inventors have demonstrated that during viral infection it is possible to observe a reduction in GSH levels as a result of the infection itself (Rotilio et al., “ Oxidative stress on cell activation in viral infection”, 143-53, 1993; Palainara et al., Antiviral Research, 27, 237-53, 1995).
Aberrant regulation of the known mechanism of apoptosis is the underlying factor responsible for numerous human diseases, such as a number of autoimmune, infectious or neurological diseases such as AIDS and cancer.
In previous studies, it has been described that resveratrol permits the elimination of tumour cells through induction of apoptosis of the cells. Recently, studies conducted by Tinhofer I. et al. ( FASEB J., 18, 1613-15, 2001) have revealed that the first events of apoptosis induced by resveratrol are characterised by alteration of the mitochondrial membrane potential (ΔΦm), by the release of reactive oxygen species (ROS) and by activation of caspases 2, 3, 6 and 9. It is also known that the influenza virus induces apoptosis in various percentages, according to the viral strain and the multiplicity of infection.
SUMMARY OF THE INVENTION
It has now been found that resveratrol exerts an inhibitory action on influenza virus replication. In an entirely surprising manner, it has also been found that resveratrol exerts its inhibitory action on influenza virus replication not through the expected antioxidant activity, but through a particular mechanism of inhibition of protein kinase C, a cell enzyme that plays a major role in the influenza virus replication process. The main advantage afforded by the use of resveratrol would therefore consist in its ability to attack the virus indirectly, i.e. by interfering with a functional cell structure of the virus, rather than with the viral particle in itself. This type of approach might therefore lead to inhibition of the virus, avoiding the occurrence of the phenomenon of resistance to the most common antiviral drugs.
Accordingly, one object of the present invention is the use of resveratrol for the preparation of a medicament useful for the prevention and/or treatment of influenza virus infections. In a preferred application of the present invention, resveratrol is used against the human influenza virus. In a broader application of the invention, its objectives also include the use of resveratrol for the preparation of a medicament useful for the treatment of influenza virus infections in the veterinary field.
The present invention will now be illustrated in detail, also with the aid of examples and figures, where:
FIG. 1 illustrates the effect of resveratrol on the replication of the influenza virus PR8 in MDCK cells, and, to be precise, in FIG. 1A in the case of post-infection administration, in FIG. 1B in the case of pre-infection administration, and in FIG. 1C in the case of pre- and post-infection administration;
FIG. 2 illustrates the effect of resveratrol on confluent monolayers of uninfected MDCK cells, and, to be precise, the number of viable cells;
FIG. 3 illustrates the characterisation of the antiviral activity of resveratrol, and, to be precise, in FIG. 3A the treatment during viral adsorption and in FIG. 3B the effect on the viral particles;
FIG. 4 illustrates the characterisation of the antiviral activity of resveratrol, and, to be precise, in FIG. 4A in the case of administration immediately after the infection and removal at different times, and, in FIG. 4B , in the case of addition at different times in relation to infection;
FIG. 5 illustrates apoptosis in MDCK cells treated with resveratrol (diamonds: not infected, squares: infected);
FIG. 6 illustrates the correlation between the antiviral effect of resveratrol and the intracellular redox state;
FIG. 7 illustrates the effect of resveratrol on the synthesis of viral proteins of the influenza virus PR8;
FIG. 8 illustrates the result of PCR for mRNA of late viral proteins;
FIG. 9 illustrates the effect of resveratrol in vivo after infection with the influenza virus PR8.
DETAILED DESCRIPTION OF THE INVENTION
For the purposes of illustrating the efficacy of the present invention, in-vitro studies have been conducted using influenza virus A/PR8/34, subtype H1N1 (hereinafter referred to in brief as virus PR8). This strain was used purely by way of an example, it being understood that the present invention is applicable to the influenza virus in the general sense of the term.
Materials and Methods
Resveratrol is a product which is commonly available on the market or which can be obtained using the known methods reported in the literature. The substance was used dissolved in DMSO (80 mg/ml). The concentrations used for the experiments were obtained by means of successive dilutions in RPMI 1640. All the control samples were treated with DMSO at the same doses used to dissolve the resveratrol. At these concentrations the DMSO produced no toxic effects on the cells.
Cell Cultures
For the study of influenza virus replication MDCK cells (dog kidney epithelial cells) were used. The cells were cultured in T-25 vials or in 6- and 24-well Libno plates in RPMI culture medium added with L-glutamine, penicillin-streptomycin and 10 % foetal calf serum (FCS) and maintained at 37° C. in a 5% CO 2 atmosphere. The confluent cell monolayers were detached with a 0.25% trypsin solution, centrifuged and reseeded in fresh medium. The cell count was done using a haemocytometer and cell viability was determined by means of exclusion with Trypan Blue viability staining (0.02%).
Production of the Virus
The virus was produced by means of inoculation of a viral suspension suitably diluted in the 10-day embryonated chicken egg allantoid cavity. After incubating the eggs at 37° C. for 72 hours, the allantoid fluid containing the newly formed viral particles was clarified by centrifuging at +4° C. and stored at −80° C.
Titration of the Virus
The titration of the virus was done using the haemoagglutinin technique which is based on the ability, peculiar to this virus, to agglutinate blood cells.
The undiluted virus in the allantoid fluid was titrated by scalar dilution with phosphate buffer saline (PBS) in 96-well plates, to which a 0.5% suspension of human blood cells of the 0 Rh+ group was later added. The plates were then left at ambient temperature long enough for the haemoagglutination reaction to take place. The viral titre of the sample, expressed in haemagglutinating units (HAU), was represented by the last dilution giving rise to complete haemoagglutination. The release of virus on the part of infected cells was evaluated with the same procedure on the supernatants of the infected samples that were drawn 24 and 48 h after infection,
Viral Infection
The confluent monolayers of MDCK cells were washed with PBS and infected with the virus (0.2 multiplicity of infection [m.o.i.]). In particular, the virus was suitably diluted in RPMI without FCS and added to the cell in the minimum volume. After 1 hour of incubation at 37° C. (period of adsorption of the virus), the inoculum was removed and the monolayers, after washing with PBS to remove the excess unadsorbed virus, were maintained in fresh medium containing 2% FCS. Resveratrol was added at various concentrations (1, 5, 10, 15, 20 and 40 μg/ml), according to the following treatment schedules: a) 24 h before infection (pre-); b) immediately after adsorption of the virus to the infection cells (post-); and c) 24 h before and immediately after adsorption of the virus to the infection cells (pre-post). In all cases, the substance was left to incubate for the entire duration of the experiment. 24 and 48 h after infection, the virus released in the supernatant was titrated by evaluation of the haemoagglutinating units. As shown in FIG. 1 , resveratrol added post-infection inhibited viral replication in a dose-dependent manner. At the concentration of 20 μg/ml, the viral titre was reduced by 87% compared to infected and untreated controls, without any toxic effects on the uninfected cells being detected. For the purposes of determining the possible degree of toxicity on the MDCK cells, the latter were treated with resveratrol after the confluence of the monolayer, at various concentrations (5, 10, 15, 20 and 40 μg/ml). The results obtained demonstrate that at the doses that caused significant inhibition of the influenza virus (10-20 μg/ml), a slight reduction in cell number was observed, probably due to a slowing-down of cell proliferation ( FIG. 2A ). At these doses, however, no morphological alterations of the cells were observed. At the concentration of 40 μg/ml, at which viral replication was completely blocked, however, toxic effects were observed with an increase in cell mortality ( FIG. 2B ). On the basis of this result, in the following experiments the dose of 20 μg/ml was used, which produced maximal antiviral activity without side effects.
Characterisation of Antiviral Activity
With the aim of identifying the phases of the viral replication cycle controlled by resveratrol, the substance was added according to different treatment schedules in relation to the various phases of the life cycle of the virus. In the first phase, for the purposes of assessing whether resveratrol interferes with entry of the virus into the cells, the substance was added at a concentration of 20 μg/ml exclusively during the viral adsorption phase (for one hour at 37° C.) and then removed. Measurement of viral replication after 24 h proved comparable to the replication obtained in the control cells, thus demonstrating that entry of the virus was not inhibited by the drug ( FIG. 3 ). Moreover, to assess whether resveratrol was capable of directly inactivating the virus, the latter was incubated with the substance at a concentration of 40 μg/ml for one hour at 37° C. Later, the virus thus treated was diluted 1:500 and used for infecting the cells. In these conditions no reduction in viral replication was observed. These results suggested that resveratrol does not directly inactivate the viral particle. In a second phase, the cells were infected and treated with resveratrol, again using the same concentration (20 μg/ml), but the substance was added at various times after infection (0, 3, 6 and 9 h). Viral replication, assessed as HAU/ml 24 h after infection, revealed that this was significantly inhibited only if resveratrol was added within 3 h of infection ( FIG. 4B ). In contrast, if resveratrol, added immediately after infection, was removed at various times (0, 3, 6, 9 and 24 h), inhibition of replication was observed only if the treatment lasted for at least 9 hours. In addition, the results presented in FIG. 4 also show that the antiviral activity, once obtained, was not reversible on discontinuing the treatment.
Viral replication was also assessed with analysis of the occurrence of viral antigens on the surface of the infected cell by means of immunofluorescence. Analysis of viral proteins by immunofluorescence was done with a fluorescence microscope using a filter emitting in the green (FITC) (lens 100×). MDCK cells, cultured on cover slides for 24 h were infected and, 18 h after infection, were fixed with methanol-acetone 1:1 at 4° C. for 15 min. Later, the cells were washed twice in PBS and permeabilised with a 0.1% solution of PBS-TRITON for 5 min. Blockade of the aspecific sites was done with 1% milk dissolved in PBS for 30 min at ambient temperature. Later, specific monoclonal antibodies (mouse anti-influenza NP and mouse anti-influenza M) to viral proteins were added, diluted 1:50 in PBS for 30 min at ambient temperature. The primary antibody was detected with a secondary antibody conjugated to fluorescein (anti-mouse FITC, Sigma).
Analysis of Synthesis of Viral Droteins and Correlation with Antiviral Activity of Resveratrol
Viral proteins were analysed by Western blotting. At different times after viral infection, the cells were lysed using special lysis buffers. Equal quantities of proteins were then loaded onto polyacrylamide gel in SDS. After electrophoresis, the proteins were transferred onto a nitrocellulose membrane and treated with anti-influenza polyclonal antibody. After incubation and suitable washings, the filters were treated with a second antibody conjugated to peroxidase and the viral proteins were highlighted by means of the chemiluminescence technique (ECL), using a peroxidase substrate (luminol) which, on reacting with the enzyme, emits a light and makes an impression on the autoradiography plate. The cells were treated with resveratrol at various concentrations (5, 10, 15 and 20 μg/ml). To allow better imaging of the viral proteins, the electrophoresis run was done using a 10% polyacrylamide gel ( FIG. 7A ) and gradient gel ( FIG. 7B ). Resveratrol at concentrations of 15 and 20 μg/ml almost totally inhibited the synthesis of the late influenza virus haemoagglutinin (H0-H1, H2) and matrix proteins (M). In contrast, the expression of early nucleocapside proteins (nucleoprotein [NP] and polymerase protein [P]) was inhibited, though to a lesser extent than that of the late proteins.
Analysis of the Synthesis of Messenger RNAs
For the purposes of identifying the mechanism of inhibition of viral proteins, MDCK cells, infected and treated with resveratrol at the different concentrations described above, were analysed by means of the PCR technique described by Tobita et al. ( J. Genteral Virol., 78, 563-566, 1997). MCDK cells infected with the virus and/or treated with resveratrol were homogenised with the reagent GIBCO BRL TRIZOL. After incubation at ambient temperature for 5 minutes, chloroform was added (0.2 ml per sample) and the samples were incubated at 15-30° C. for 3 minutes, Then, they were centiifuged at 10,000 rpm for 15 min at +4° C. and the aqueous phase containing the RNA was recovered. 0.5 ml of isopropanolol were added and the samples were incubated at 15-30° C. for 10 min and then centrifuged. The supernatants obtained were removed and the RNA precipitate was treated with 75% ethanol at 8,000 rpm for 5 min at 2-8° C. Lastly, the precipitate was air dried and dissolved in 20 μl of water-DEPC (diethyl pyrocarbonate).
The RNA obtained was transcribed using reverse transcriptase. The retrotranscription was done on 5 μl of RNA of each sample in a mixture consisting of random primers, the four deoxynucleotides (dNTP=cIATP, dCTP,dGTP, dTTP), dithiotreitol (DTT), and RT buffer (Life Technologies). The synthesis of complementary DNA (cDNA) was done by leaving the mixture for 10 min at 22° C., then for 60 min at 42° C. and finally the reaction was inactivated for 10 min at 75° C. The cDNA thus obtained was then used in PCR.
Taq polymerase was used in PCR. PCR was conducted in its three phases of denaturing, annealing and elongation at the respective temperatures of 95, 48 and 72° C. The cycle was repeated 20 times. The oligonucleotides used for the viral RNA amplification were: for the viral gene coding for the haemoagglutinin protein (HA) 5′ primer: 5′-ACCAAAATGAAGGCAAACC-3′, 3′ primer: 5′-TTACTGTTAGACGGG-TGAT-3′; for the viral gene coding for the matrix protein (M) 5′ primer: 5′-ATGAGTCTTCTAACCG-3′, 3′ primer: 5′-ACTGCTTTGTCCATGT-3′. The PCR product was run in electrophoresis (100 volts) on a 1% agarose gel in a buffer in which ethidium bromide had been placed to display the DNA with a UV transilluminator.
The samples obtained were evaluated at 4, 8 and 20 h, respectively, after viral infection. Messenger RNAs for the viral proteins HA and M were not observed at 4 h either in the control or in the group treated with resveratrol. The results show that the synthesis of the mRNAs 20 h after infection is not affected by treatment with resveratrol. The observation at 4 h shows that resveratrol causes only a delay in messenger synthesis for these proteins ( FIG. 8 ). These results suggest that reservatrol at doses of 20 μg/ml causes a delay in the release of messenger RNAs for the late viral proteins (HA and MV), evaluated 8 hours after infection.
Localisation of Protein NP
Considering that the inhibition of protein kinase C in cells infected by the influenza virus causes a substantial reduction in protein M expression, together with retention of the nucleoprotein of the nucleus of the infected cell ( J. Virol., 74, 1781-86, 2000), MDCK cells infected with the virus PR8 and treated or not with resveratrol at the concentration of 20 μg/ml were stained with specific anti-M and anti-NP antibodies and observed under the fluorescence microscope. The results revealed that, whereas in the uninfected cells NP is observed both in the nucleus and in the cytoplasm and M 1 prevalently in the cytoplasm, in cells treated with resveratrol the NP is retained in the nucleus and M, which is significantly inhibited, can equally be observed only in the nucleus. This phenomenon may be attributable to inhibition of cell proteins with a kinase function. The data suggest then that the antiviral action mechanism may be related to the inhibition of proteins with a kinase function described above ( FEBS Letters, 45, 63-7, 1999).
Assay of Reduced and Oxidised Alutathione
The glutathione assay has been performed as a result of the formation of S-carboxymethyl-derivatives of free thiols with iodoacetic acid followed by conversion of the NH 2 terminal groups to 2,4-dinitrophenyl derivatives after the reaction of 1-fluoro-2,4-dinitrobenzene ( Anal. Biochemn., 106, 55-62, 1980).
The MDCK cells were detached by means of the scraping technique. Later, the cells were centrifuged at 1,200 rpm for 5 minutes. The cells were washed twice in PBS and the precipitate, obtained after centrifuging, was resuspended in 200 μl of buffer. The cell lysates, obtained with repeated cycles of freezing and thawing, were deproteinised by means of precipitation in 5% metaphosphoric acid. After centrifuging at 22,300 g, the low-molecular-weight thiols present in the supernatant were derivatised with 10% iodoacetic acid v/v and neutralised with NaHCO 3 in powder form. After 1 h of incubation in the dark a solution of 1.5% 1-chloro-2,4-dinitrobenzene v/v was added (1.5 ml/98.5 ml of absolute ethanol). After adding the Sanger reagent, the samples were incubated for 12 h in the dark, and the separation of the various species of glutathione was done by means of a μBondapak 3.9×300 mm (Millipore) NH 2 HPLC column. To measure the total GSH content reference was made to a standard curve obtained with purified GSH. The GSH content is expressed in GSH nmol/mg proteins present in the lysate sample. The protein concentration was calculated using the Lowry method ( Biol. Chem., 193, 265-75, 1951). This method exploits the ability of proteins to reduce the Folin-Ciocalteau reagent in an alkaline solution with Cu2 + ions, thanks to the presence of the phenol groups of a number of amino acids such as tryptophane, tyrosine, cysteine and histidine. Tryptophane and tyrosine react by means of their particularly reactive phenol groups, cysteine through the —SH group and histidine with the imidazole ring. The reducing reaction product is detected by the formation of stained compounds by reaction with the aromatic amino acids of the proteins. In fact, the solution takes on a particularly intense blue colour which has peak absorption at 695 nm. On the basis of the proportions of the absorption, the concentration of the proteins is therefore obtained in relation to a straight line calibration curve obtained using various concentrations of drum bovine albumin as the standard.
For the purposes of evaluating the possible correlation between antiviral activity and modulation of the redox state, the concentration of the cellular GSH of MDCK cells, treated with different reseivatrol concentrations and infected or not with the virus, was assessed by HPLC analysis 24 h after infection, Surprisingly, resveratrol added to uninfected MDCK cells produced a reduction in intracellular GSH levels as compared to untreated cells ( FIG. 6 ). The addition of resveratrol to infected cells, though inhibiting viral replication, did not restore the GSH levels reduced by the infection.
Analysis of Apoitosis
As regards the analysis of apoptosis. MDCK cells were infected with the virus PR8. After viral adsorption, the cells were treated with resveratrol at various concentrations (5, 10, 15 and 20 μg/ml). Twenty-four hours after infection, the cells were detached using a 0.25% trypsin solution and then centrifuged at 1,200 rpm for 5 min, The precipitate thus obtained was analysed by means of the FACS technique after labelling with propidium iodide.
For the purposes of assessing whether the induction of cell death by apoptosis was involved in the antiviral effect of reservatrol, MDCK cells were infected or not with the virus and treated with the substance at the various concentrations. Cell death by apoptosis was evaluated by FACS after labelling with propidium iodide. As shown in FIG. 5 , reservatrol caused a certain degree of cell death by apoptosis in uninfected cells ranging from 8 to 32% according to the doses (5 and 20 μg/ml, respectively). The infection in itself induced apoptosis in 12% of infected cells. Although the addition of increasing doses caused an increase in the mortality, no significant difference was observed between infected cells and uninfected cells treated with antiviral doses of the drug (35 and 37% apoptosis, respectively).
By way of further confirmation of the results of the present invention, and by way of examples, the following in-vivo studies are described.
EXAMPLE
Four-week-old female inbred Balb/c AnCrIBR mice were used. Resveratrol, dissolved in PBS, was administered to the animals via the intraperitoneal route at various times after infection with the influenza virus. The reservatrol concentrations were chosen so as to obtain a range of doses in the animals' blood similar to the effective range in vitro (10 to 20 μg/ml).
The mice were inoculated intranasally (i.n.) with a suspension containing the influenza virus A/PR at a multiplicity of infection of 2 HAU/mouse, after light anaesthesia with ether. On the basis of previous experimental data, the influenza virus at this multiplicity of infection produces haemorrhagic pneumonia that leads to the death of 80% of the animals by one week after infection. For the purposes of monitoring the infection trend, both virological and immunological parameters were monitored in addition to studying survival curves.
As a virological parameter, the viral load was determined. At different times after infection, the lungs of infected and control mice were taken as samples, weighed and homogenised in RPMI containing antibiotics. After centrifuging, the supernatants were suitably diluted and the viral load was analysed by means of the CPE-50% test. On the basis of this method, confluent MDCK cells were infected with the supernatants serially diluted in RPMI added with antibiotics at 2% FCS and incubated for three days at 37° C. in a 5% CO 2 atmosphere. Lastly. For each dilution, the wells showing positive effects were counted and compared with those showing negative cytopathic effects according to the Reed and Muench formula. The CPE-50% titre was calculated in units/ml.
As an immunological parameter, levels of inflammatory cytokines were evaluated using the ELISA method. A 96-well plate was used for the experiment. The plate was coated with monoclonal antibodies to the cytokines to be studied, incubated overnight at 4° C. Later, 200 μl/well of 1% BSA in carbonate buffer were added for 30 min at 37° C. Washings were then done with 0.25% TBS+Tween 20 and the samples were added for 4 hours at 37° C. As a reference curve recombinant cytokines in scalar dilution were used. Washings were then performed and an anti-cytokine polyclonal antibody, different from the first one, was added and left overnight at +4° C. Later, to washings with 0.5% TBS+Tween 20, MgCl 2 2 nM was added the third antibody conjugated to the anzyme alkaline phosphatase for 4 h at 37° C. Lastly, a substrate for the enzyme (100 μl/well) was added and the readout was taken using the ELISA reader and a 405 nm filter. The following antibodies were analysed: 1) monoclonal rat anti-mouse TNF-alpha/recombinant mouse IL-6; 2) recombinant mouse TNF-alpha/recombinant mouse IL-6; 3) polyclonal rabbit anti-mouse TNF-alpha/polyclonal goat anti-mouse IL-6; 4) goat anti-rabbit IgG-alkaline phosphatase/anti-goat IgG alkaline phoshatase.
The efficacy of resveratrol was studied in an experimental influenza virus infection model in the mouse. In this model, intranasal inoculation of the virus causes severe haemorrhagic pneumonia which leads to the death of the animals within 7 to 10 days of infection. The experimental design envisages evaluation of the therapeutic efficacy of the study substance, as assessed on the basis of survival of the infected animals. To this end, resveratrol was administered to the animals at various doses, on a daily basis for 7 days, starting from a few hours after infection. The results obtained show that, whereas the mortality of the untreated animals was as high as 80%, the administration of resveratrol (1 mg/kg) significantly reduced the mortality and 60% of the animals survived the infection ( FIG. 9 ). | The use of resveratrol is described fir the preparation of a medicament for the treatment of influenza. Said medicament exerts itself in therapeutic activity through inhibition of viral replication. | 0 |
This is a division of application Ser. No. 08/339,217 filed Nov. 10, 1994, now abandoned, which is a division of application Ser. No. 08/070,801 filed Jun. 3, 1993, now U.S. Pat. No. 5,420,712.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a scanning device for scanning an image recorded on a film.
2. Related Background Art
In order to read a recorded color image, each of the red, green and blue images must be read. In order to reduce a size of this type of device, it has been proposed to use a plurality of LED's for red, green and blue as illumination sources. However, because the presently available LED has a big difference in intensity depending on the color of light emission, the number of LED's used is varied depending on the color of light emission.
Since the light intensity of the LED is very small depending on the color of light emission and the number of LED's used is limited in order to reduce the size of the device, it is necessary to efficiently operate the LED's.
Further, since a limited number of LED's are used depending on the color of light emission, non-uniformity of illumination occurs. Accordingly, it is necessary to eliminate a component of a light source which adversely affects the image quality.
SUMMARY OF THE INVENTION
The scanning device of the present invention scans an original which is set at a predetermined position and has information recorded thereon. The present scanning device comprises: a plurality of light emission members for emitting lights of different wavelengths from each other; a first reflection member having a plurality of reflection planes for selectively reflecting lights of a plurality of wavelengths coming from by the light emission members and optical aid means; a second reflection member for reflecting the light reflected by the first reflection member to focus it on the original in a linear pattern; and focusing means (an imaging optical system) for focusing the information of the original onto a sensor in accordance with the reflected light from the second reflection member.
The device has depressions arranged around the light emission members for reflecting lights of the emission members and the depressions are shaped differently depending on the wavelengths of the light emissions of the corresponding light emission members so that increased light intensities of the respective wavelengths of light emissions and decrease non-uniformity of the light intensity are attained.
In the present device, the light intensity on the original increases when optical distances from the respective light emission members to the original are equal.
In the present device, the position adjustment of the sensor is facilitated by arranging the original slightly off the focal point of the light focused by the second reflection member so that the non-uniformity of the light intensity of the light illuminating the original is reduced.
In the present device, when the focusing means is a lens and the light projected by the second reflection member is converged such that the information light from the original does not fill an aperture of the lens, flare is prevented and a high contrast image is produced.
In the present device, infrared light which adversely affects performance may be eliminated by reflecting only a visible light or a light of only a waveform necessary for scanning.
In the present device, the light intensity on a center axis of a linear arrangement of light emission members is increased by arranging the light emission members such that a maximum light intensity of the light emission members is arranged around the center axis.
In the present device, the leakage of the reflected light is prevented by providing focusing means for focusing the reflected light from the first reflection member to the second reflection member.
In the present device, a high efficiency is attained by arranging the light emission members in a line and arranging the light emission members such that a maximum light intensity of the light emission members is arranged around the center axis of the line. Where LED's of generally square shape are used as the light emission members, it is preferable that the LED's are arranged such that one side of the square is inclined from the axis of the line by approximately 30 degrees.
In another aspect, the present invention relates to a light projection device for a scanning device for scanning an original having information recorded thereon. The device comprises a plurality of light emission members for emitting lights of different wavelengths from each other, and optical aid means arranged around the light emission members for focusing the lights of different wavelengths emitted by the plurality of light emission members. The light emission members are arranged in a line and also arranged such that a maximum light intensity of the light emission members is arranged around the center axis of the linear arrangement of light emission members. The optical aid means have different shapes depending on the wavelengths of the lights emitted by the corresponding light emission members. Where the LED's of generally square shape are used as the light emission members, the LED's are arranged such that one side of the square is inclined from the axis of the line by approximately 30 degrees.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a device for forming an image in one embodiment of the present invention;
FIGS. 2A and 2B show detail of a light source 601 in FIG. 1; and
FIG. 3 shows a line arrangement of LED chips and a light emission member 301 of the LED chip and depressions 302 and 303.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 shows a device for forming an image in one embodiment of the present invention.
In FIG. 1, the device comprises a light source 601, a concave mirror 611, a mirror 620, a mirror 621, an image forming lens 631 and a sensor 641.
The light source 601 uses LED chips of three colors as a light emission source.
The concave mirror 611 is of toroidal design, that is, it is a mirror having curvatures of two different axes for linearly focusing the light from the light source 601 onto a plane of a film 622.
The mirror 620 reflects the light reflected by the concave mirror 611 to direct it to the plane of the film 622.
The mirror 621 reflects the light transmitted through the film 622 to the image forming lens 631.
The image forming lens 631 focuses the reflected light from the mirror 621 onto the sensor 641.
The sensor 641 is a CCD which converts the light focused by the image forming lens 631 to an electrical signal.
The film 622 may be a negative film or a positive film having light transparency.
FIGS. 2A and 2B show detail of the light source 601 of FIG. 1.
In FIGS. 2A and 2B, the light source 601 comprises two red LED chips, four green LED chips, six blue LED chips, a support table 650, a dichroic mirror 660, an infrared blocking filter 661, a common lead 670, a blue lead 671, a red-green lead 672 and an insulator 680.
The red LED chip uses GaAlAs (gallium aluminum arsenide) as a material and has a cathode electrode on a top light emission plane and an anode electrode on a bottom surface. The green LED chip uses GaP/GaP (gallium phosphor/gallium phosphor) as a material and has an anode electrode on a top light emission plane and a cathode electrode on a bottom plane. The blue LED chip uses SiC (silicon carbide) as a material and has an anode electrode on a top light emission plane and a cathode electrode on a bottom plane. They generate lights of red, green and blue, respectively.
Six LED chips are arranged on the support table 650 in two lines, namely, the red LED chips and the green LED chips in one line and the blue LED chips in one line. In the line of the red and green LED chips, they are arranged in the order of green, red, green, green, red and green. They are arranged by taking the non-uniformity of illumination due to the difference in numbers into consideration, although the present invention is not limited thereto and further improvement may be attained by changing the distances between the LED chips.
The numbers of LED chips of different colors used are different because of a substantial difference between light emission intensities per chip of the presently available LED chips of various colors. However, since the illumination light intensity may not be made uniform by merely changing the numbers of chips, the light emission times of the LED chips of the respective colors may be adjusted when the image is read.
The respective LED chips are arranged such that the optical distances from the light emission surfaces of the respective LED chips to the exit planes are equal. As a result, the lights of all colors are focused on the film 622.
The support table 650 is made of a conductive material.
The common lead 670 is electrically connected to the support table 650 and the blue lead 671 and the red-green lead 672 are insulated from the support table 650.
The common lead 670 is connected to the anodes of the red LED chips, the cathodes of the green LED chips and the cathodes of the blue LED chips through the support table 650.
The blue lead 671 is insulated from the support table 650 by an insulator 680, and wire-bonded to the anodes of the blue LED chips.
The red-green lead 672 is insulated from the support table by the insulator 680 and wire-bonded to the cathodes of the red LED chips and the anodes of the green LED chips.
It is necessary to arrange the red LED chips and the green LED chips which use the common lead, in the opposite polarities so that the red, green and blue LED chips can independently emit lights. Since the red LED chip and the green LED chip used in the present embodiment are of opposite polarities as described above, a vertical arrangement for all LED chips may be used.
The dichroic mirror 660 comprises a dichroic plane 666 and an aluminum plane 667 coated by an aluminum layer. The blue light emitted from the blue LED chip is reflected by the dichroic plane 666, and the red and green lights emitted from the red and green LED chips pass through the dichroic plane 666 and are reflected by the aluminum plane 667. Those reflected lights pass through the same light path on an exit plane.
The blue LED chip which uses SiC as the material emits not only the blue light but also a small quantity of green light. Since a blue reflection film for selectively reflecting only the blue light is applied to the dichroic plane 666 of the dichroic mirror 660, the green light from the blue LED chip is not reflected. However, the aluminum plane 667 reflects the green light emitted by the blue LED chip. This will deteriorate the image quality. Thus, the dichroic mirror 660 is arranged in such a manner that a strong light around the axis of the line of the blue LED chips is reflected by the aluminum plane 667 and does not go out of the exit plane. A weak light which goes out of the exit plane is weak by itself and defocused on the film 622 so that it does not significantly affect the image quality.
The infrared blocking filter 661 is provided on the exit plane of the light source 601 and it prevents the degradation of the image quality by the infrared component included in the red LED light. The infrared blocking filter 661 is not necessary when the aluminum plane 667 of the dichroic mirror 660 is a reflection plane which reflects only a visible light. The color reproducibility may be improved by forming a reflection film which reflects only a desired wavelength.
Where the exit plane of the light source 601 is cylindrical or toroidal, the illumination light is focused and a larger amount of light may be reflected from the concave mirror 611.
The dichroic mirror 660, the LED chips and the infrared blocking filter 661 are integrally assembled by epoxy which is an optical material.
FIG. 3 shows a line arrangement of the LED chips and the light emission portion 301 of the LED chip and the depressions 302 and 303.
In FIG. 3, each of the LED chips has the light emission portion 301 of generally square shape when viewed from the top and is arranged such that the light emission portion 301 of the LED chip is inclined around the center thereof to the line axis AX by an angle θ which is about 30 degrees in the illustrative embodiment.
Since the LED chip has a property of emitting strong lights from four corners of the square, it is arranged such that the four corners are not away from the center axis of the line to increase the light intensity around the center axis of the LED chips.
The depressions 302 and 303 have silver plating or rhodium or gold plating applied to the surfaces thereof to efficiently direct the lights from the LED chips. Since the number and the shape of the LED chips, the position of the light emission portion 301 and the transparency of the chip varies from color to color, the height, the inclination angle and the curvature of the slope are different. The spread of undesired light can be suppressed by forming the slope as elliptic or parabolic.
When the depression 302 is elliptic having a major axis along the line axis of the LED chips when viewed from the top, the light intensity around the axis of the LED chip line is increased.
The non-uniformity of the illumination can be reduced for the red LED chips which are used in a small number by increasing the major axis of the ellipse of the depression 302.
A light path is briefly explained by referring to FIG. 1.
The light source 601 emits one of the red, green and blue lights.
The light is reflected by the concave mirror 611 and the mirror 620 and a light focused in line pattern is irradiated to the plane of the film 622. A maximum light intensity is attained by focusing onto the film 622.
The light transmitted through the film 622 is reflected by the mirror 621 and directed to the image forming lens 631.
If the illumination light totally illuminates a lens, flare may take place. In order to attain an image of a higher contrast, the illumination light is converged so as to fill 70 percent of the lens aperture. This may be attained by spacing the optical distance of the image forming lens 631 from the film 622.
The line image formed by the image forming lens 631 on the sensor 641 is converted to an electrical signal by the sensor 641.
The red, green and blue lights are illuminated to one line of the film 622 and the film 622 is moved to the next read line along the X axis by a drive unit, not shown, and the same process is repeated for that line.
A plurality of line information supplied from the sensor 641 are processed by a control unit, not shown, and supplied to a monitor.
A second embodiment of the present invention is now explained.
In the present embodiment, the optical distance from the light source 601 to the film 622 is slightly shifted.
As a result, the light is not focused on the plane of the film 622 so that the line illumination light on the film 622 has a width (which is less than 1 mm in order not to decrease the illumination light intensity more than required) and the line image formed on the sensor 641 also has a width.
As a result, the positioning for focusing on the sensor 641 is facilitated. Further, fine positioning of the film 622 is not necessary. Further, since the illumination light is defocused, the non-uniformity of the illumination is reduced.
In a third embodiment of the present invention, the red LED chips which are used in a small number in the first embodiment are arranged slightly closer to the dichroic mirror 660. As a result, the red light is not focused on the film 622 and the line red illumination light on the film 622 has a width so that the line image formed on the sensor 641 also has a width.
As a result, the positioning of the sensor 641 is facilitated by using the red light. Further, since the defocusing reduces the non-uniformity of the illumination, it is preferable to shift the red LED chips which are small in number and have a relatively large non-uniformity of the illumination.
While the red LED chips are arranged to be slightly closer to the dichroic mirror 660 in order to defocus the light in the present embodiment, they may be arranged further therefrom to obtain the defocusing. However, they are arranged to be closer in the present embodiment in order to prevent the light intensity from being reduced.
Since the light intensity decreases when the light is defocused, the positions of the LED chips which have high illumination light intensity may be shifted. In the present embodiment, the red LED chips correspond to such LED chips.
In the above embodiments, the light is transmitted through the recording medium such as the film. Alternatively, the present invention is applicable to a device which reflects the information of the recording medium to read it.
Since the optical aid means is provided in the present invention, the light from the light emission member can efficiently directed.
By making the optical distances from the light emission members to the recording medium equal, the light intensity on the recording member increases.
By focusing the light slightly off the recording medium, the positioning of the sensor is facilitated and the non-uniformity of the light intensity of the light illuminating the recording medium is eliminated.
By converging the light such that the lens aperture is not filled, flare is prevented and a light image of a high contrast is attained.
By providing the reflective depressions which are different depending on the wavelength of the light emission are provided, the light intensities are increased and the non-uniformity of the light intensity is reduced for the respective wavelengths of light emission.
By providing a first reflection member that reflects only the visible light or a light of only a desired wavelength, no adverse affect to the information is produced and the infrared ray is not reflected.
By disposing the LED chips so that they are inclined approximately 30 degrees to arrange the four corners around the center axis in order to bring the maximum light emission portion of the light emission member around the center axis of the light emission member, the light intensity on the center axis of the line increases.
By providing focusing means for focusing the reflected light from the first reflection member to the second reflection member, the leakage of the reflected light is prevented. | A scanning device for scanning an original which is set at a predetermined position and has information recorded thereon comprises: a plurality of light emission members for emitting lights of different wavelengths from each other; a first reflection member having a plurality of reflection planes for selectively reflecting emitted lights of a plurality of wavelengths coming from the light emission members and an optical aid portion; a second reflection member for reflecting the lights reflected by the first reflection member to focus them on the original in a linear pattern; and an imaging optical system for focusing the lights of the linear pattern onto a sensor, whereby the sensor receives the information of the original. The device has depressions arranged around the light emission members for reflecting lights and the depressions are shaped differently depending on the wavelengths of the light emissions of the corresponding light emission members so that increased light intensities of the respective wavelengths of light emissions and decrease non-uniformity of the light intensity are attained. | 8 |
FIELD OF THE INVENTION
The present invention is directed to devices for aligning sheets. An alignment cylinder is shiftable axially. A feed table, that guides the sheets to the alignment cylinder, is also shiftable in the axial direction of the alignment cylinder.
BACKGROUND OF THE INVENTION
A device and a method for aligning sheets is known from EP 0 120 348 A2. There, the alignment of the front edges of the sheets takes place in a way wherein the sheets, arranged in the manner of fish scales, are fed to the device and are fed to an alignment cylinder of the device at a conveying speed which is greater than the circumferential speed of the alignment cylinder. Front lays are arranged on the circumference of the alignment cylinder, and against which the front edges of the sheets can be placed. Because of the relative speeds of the sheets and the front lays, the front edge of the sheet is braked at least slightly, and the front edge of the sheet is aligned because of this. Following the alignment of the front edge of the sheet, the area of the front edge of the sheet is fixed on a suction strip carried by the alignment cylinder by the application of a vacuum to the suction strip. The sheet is looped around the circumference of the alignment cylinder because of the continued rotatory driving of the alignment cylinder. Following the alignment of the front edge of the sheet and prior to transferring the sheet to a downstream-located device, a lateral offset of a lateral edge of the sheet is measured by a measuring device. The suction strip, on which the front edge of the sheet is fixed, is linearly displaced axially in the direction of the axis of rotation of the alignment cylinder as a function of the result of the measurement in order to align the lateral edge of the sheet in accordance with the desired alignment. The result of this is that the sheet can be transferred, placed in the correct position in regard to its front edge, as well as to a lateral edge, to a subsequent device, for example a sheet-printing press.
A device for sheet guidance of a sheet-fed rotary printing press is known from DE 23 13 150 C3. The sheets are conducted on a feed table in scaled layers to the device and then away from the device. The use of suction rollers, on whose circumferences recesses are provided, for conveying the sheets, which are lying flat on the feed table, is described. The sheet can be fixed on the circumference of the suction roller by the application of a vacuum. In this device, the suction roller is arranged in a recess of the feed table in such a way that the sheets, which lie flat on the feed table and are placed tangentially against the circumference of the suction roller, can be driven. It is achieved by this that the respective sheets come into contact with the suction roller only in a line-shaped contact area. The driving forces are frictionally transmitted, by the suction roller, to the sheet in the line-shaped contact area. Thus no looping of the sheets around the suction rollers is required.
A device with a suction drum is known from WO 97/35795 A1, and to whose circumference the sheets to be conveyed can be frictionally fixed by the application of a vacuum. In this case, the drive mechanism of the suction drum is structured in such a way that the number of revolutions and/or the angle of rotation of the suction drum can be controlled by an independent electrical motor in accordance with pre-selected movement laws.
A sheet-feeding device for printing presses is known from DE-AS 20 46 602. The lateral offset of a lateral edge of a sheet, in relation to a desired orientation, can be detected by a measuring device. For aligning the lateral edge of the sheet, it is possible to displace an alignment cylinder, on whose circumference the sheet is fixed, axially, in the direction of the cylinder's axis of rotation, as a function of the measurement result.
A device for measuring the position of the lateral edge of a sheet is known from EP 0 120 348 A2. This measuring device essentially consists of two measuring heads which, for measuring the position of the lateral edges, work together with interrogation gaps that are arranged at the circumference of a conveying roller. In order to be able to set the measuring heads to accommodate different sheet widths, the measuring heads are manually displaceable on a supporting cross-beam which is arranged above the sheet conveying level.
A contactless operating device for measuring the position of sheets is known from EP 0 716 287 A2. The lateral edges of the sheets can be measured by an optical system.
SUMMARY OF THE INVENTION
The object of the present invention is directed to providing devices for the alignment of sheets.
In accordance with the present invention, this object is attained by the use of a sheet alignment device that has an alignment cylinder which can be shifted in its axial direction. A feed table, which guides sheets to the alignment cylinder, can also be shifted in the axial direction of the alignment cylinder. The alignment cylinder has at least one front register lay. The circumferential speed of the alignment cylinder is selected to be 0.7, to 0.9 times the sheet conveying speed when the sheet front edge contacts the front register lays. A sheet hold-down roller, which can work in cooperation with the alignment cylinder, has a helical cross-sectional shape.
The advantages to be obtained by the invention consist, in particular, in that, in the course of being conveyed by the alignment cylinder, the sheets can be simultaneously aligned in respect to their front edge, as well as in respect of their lateral edge. The alignment of the sheets, in respect to their lateral edge, can be advantageously achieved in that, following the alignment of the sheet front edge at the front lays, the alignment cylinder is axially displaced in the direction of its axis of rotation.
It is furthermore advantageous if the drive motor for the rotational driving of the alignment cylinder can be controlled or regulated as a function of predetermined movement laws, in particular as a function of the alignment cylinder angle of rotation. By this, it becomes possible to also take over sheets of different lengths in the correct position at the front lay by varying the circumferential speed of the alignment cylinder during its rotation, and to transfer the sheets, now exactly aligned, to downstream-located sheet conveying devices.
BRIEF DESCRIPTION OF THE DRAWINGS
Preferred embodiments of the present invention are represented in the drawings and will be described in greater detail in what follows.
Shown are in:
FIG. 1 , a cross-sectional view of a first embodiment of a device for the continuous alignment of sheets in accordance with the present invention,
FIG. 2 , the device in accordance with FIG. 1 , showing an enlarged portion during a first phase for aligning the front edge of a sheet,
FIG. 3 , the device in accordance with FIG. 2 in a second phase for aligning the front edge of a sheet,
FIG. 4 , the device in accordance with FIG. 1 in longitudinal section taken along the section line I—I of FIG. 1 ,
FIG. 5 , a longitudinal view of a second embodiment of a device in accordance with the present invention,
FIG. 6 , the device in accordance with FIG. 5 in cross section,
FIG. 7 , a perspective view of a sheet feeder in accordance with a third embodiment of the present device,
FIG. 8 , the sheet feeder in accordance with FIG. 7 in a second perspective plan view,
FIG. 9 , the sheet feeder in accordance with FIG. 7 in section in a perspective plan view,
FIG. 10 , the seating of the alignment cylinder for the sheet feeder in accordance with FIG. 7 in a perspective plan view,
FIG. 11 , the sheet feeder in accordance with FIG. 10 with a feed table and with schematically represented sheets, in a perspective plan view,
FIG. 12 , a perspective view of an embodiment of a sheet conveying device for a sheet feeder in accordance with FIG. 7 ,
FIG. 13 , a perspective view of a sheet guidance device for a sheet feeder in accordance with FIG. 7 ,
FIG. 14 , a first phase, during the alignment of a moving sheet, in a sheet feeder in accordance with FIG. 7 in a perspective plan view,
FIG. 15 , a second phase, during the alignment of the sheet, in accordance with FIG. 14 in a perspective plan view,
FIG. 16 , a phase during the alignment of the sheet in accordance with FIG. 14 in a perspective plan view,
FIG. 17 , diagrams showing path, speed and acceleration of the rotational movement of an alignment cylinder applied over the angle of rotation of the alignment cylinder during one revolution,
FIG. 18 , diagrams showing path, speed and acceleration of the linear movement of an alignment cylinder axially in the direction of its axis of rotation applied over the angle of rotation of the alignment cylinder during one revolution,
FIG. 19 , a top perspective view of a device for measuring the position of the lateral edges of a sheet in a sheet feeder in accordance with FIG. 7 ,
FIG. 20 , the device in accordance with FIG. 19 , in a perspective view from below,
FIG. 21 , the device in accordance with FIG. 19 , in a lateral plan view from the rear,
FIG. 22 , the device in accordance with FIG. 19 , in a lateral plan view from a transverse side,
FIG. 23 , the device in accordance with FIG. 19 , in a partially sectional representation in a perspective plan view,
FIG. 24 , the drive mechanism of the device in accordance with FIG. 19 , in a perspective plan view,
FIG. 25 , a gear stage of a device in accordance with FIG. 19 , in a perspective plan view from below,
FIG. 26 , the drive motor of a device in accordance with FIG. 19 , in a perspective plan view from below,
FIG. 27 , a cover element for a device in accordance with FIG. 19 , with an associated guide device, in a perspective plan view from below,
FIG. 28 , a partial element of a coupling element in accordance with the present invention, in a perspective plan view,
FIG. 29 , a perspective view of a further partial element of a coupling element,
FIG. 30 , a coupling element in a perspective plan view,
FIG. 31 , a coupling for transmitting a driving torque to an axially displaceable shaft, in a lateral view,
FIG. 32 , a coupling in accordance with FIG. 31 during a first phase for the rotational drive of an axially displaceable shaft, and in
FIG. 33 , a coupling in accordance with FIG. 32 during a second phase for the rotational drive of an axially displaceable shaft.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
A device 02 for aligning sheets 01 , in accordance with a first preferred embodiment of the present invention, is represented, partly in cross section, in FIG. 1 . Devices of this type are used for aligning sheets, which are conveyed to the device in an overlapping or shingled manner from a device for overlapping, which is not represented, in their correct positions so that the sheets, now correctly aligned, can be transferred to a downstream-located web-fed printing press, for example. As depicted in FIG. 1 , the sheets 01 , which are lying one behind the other, are fed to the device 02 in such a way that each front edge 07 of the respectively rear or trailing sheet 01 rests underneath the sheet 01 respectively leading, or lying in front of it. The device 02 is used, in particular, to align the sheets 01 , conveyed in an overlapping manner during their conveyance through the device 02 , in their correct position in respect to the sheet front edge 07 and in respect to the sheet lateral edge so that, after leaving the device 02 , the sheets 01 can be conveyed, in their correct position, to a downstream-located device 03 , such as, for example, a transfer cylinder 03 of a web-fed printing press. An alignment cylinder 04 , which is substantially constructed of a drive shaft 05 and suction rollers 06 , which suction rollers 06 are arranged spaced apart on drive shaft 05 , is used for aligning the sheet 01 in the device 02 , as seen in FIG. 4 . The alignment cylinder 04 has a diameter of between 140 mm and 150 mm, and in particular has a diameter of approximately 144 mm. The function of the device 02 , in the course of aligning the front edge 07 of the sheets 01 , can be seen in FIGS. 2 and 3 in particular.
The upper portion, which is embodied in the manner of a suction roller 06 , of the alignment cylinder 04 is represented in FIG. 2 . A front lay 08 , against whose front the front edge 07 of the sheets 01 can come to rest for aligning the front edge 07 of the sheets 01 , is fastened on the circumference of the alignment cylinder 04 along a line extending parallel with the axis of rotation of the alignment cylinder 04 . The alignment cylinder 04 is driven at a circumferential speed which is at least slightly less than the conveying speed of the sheets 01 on a feed table 09 . The sheets 01 are conveyed to the device 02 synchronously with the movement of the front lay 08 , so that each front edge 07 can reach the contact area of the front lay 08 . Because of the relative speed differential between the front lay 08 and the sheet front edge 07 , the sheet front edge 07 runs up to, and against the front lay 08 and because of this it can be continuously aligned during the contact phase between the sheet front edge 07 and the front lay 08 . It has been shown to be particularly advantageous if, during the contact between the front lay 08 and the front edge 07 of the sheet 01 , that the circumferential speed of the alignment cylinder 04 corresponds, at least at times, to approximately 0.7 to 0.9 times, and in particular to 0.8 times, the conveying speed of the layered sheets 01 immediately prior to contact between the front lay 08 and the front edge 07 of the sheet. “Immediately prior to contact . . . ” means “during first contact”. The alignment cylinder 04 performs one revolution for each conveyed sheet 01 .
The front lay 08 has a height of 2 mm to 4 mm, and in particular, has a height of 3 mm, above the circumference of the alignment cylinder 04 .
In order to be able to align the sheet 01 exactly on the front lays 08 , a sheet hold-down roller 11 is arranged opposite the alignment cylinder 04 . A recess 12 is provided on the circumference of the sheet hold-down roller 11 in such a way that, as can be seen in FIG. 3 , the front lay 08 on the alignment cylinder 04 can be received in a contact-free manner when passing through the gap between the alignment cylinder 04 and the sheet hold-down roller 11 . The sheet hold-down roller 11 is driven by the alignment cylinder 04 through an appropriate gear arrangement, not specifically shown, and at a gear ratio 1:1, so that the alignment cylinder 04 and the sheet hold-down roller 11 move synchronously. The outer diameter of the sheet hold-down roller 11 is helically configured, wherein the largest radius of the sheet hold-down roller 11 is arranged approximately in the area of the recess 12 for the front lay 08 . It is achieved by this configuration of the sheet hold-down roller that the gap between the sheet hold-down roller 11 and the alignment cylinder 04 is minimized during each alignment phase of the front edge 07 . Thereafter the gap is increased again in the course of the further rotation of the sheet hold-down roller 11 so as not to hamper the conveyance of the sheets 01 .
A hold-down plate 13 , which is arranged in an inlet area 14 , as seen in FIGS. 2 and 3 , is also used for stabilizing the sheets 01 during their alignment at the front lay 08 . In order to be able to configure the sheet alignment device 02 optimally as a function of the various method parameters, in particular as a function of the paper quality used, it is possible to support the feed table 09 and/or the hold-down roller 11 and/or the hold-down plate 13 so that they can be adjusted in height in respect to the alignment cylinder 04 . Based on the method parameters to be taken into consideration, the distance between a hold-down roller tangential plane 16 , measured when the maximum radius of the sheet hold-down roller 11 passes the alignment cylinder 04 , should be a distance of approximately 0.8 mm from the surface 17 of the feed table 09 . The alignment cylinder 04 is arranged below the feed table 09 in such a way that the sheets 01 come into contact substantially tangentially with the circumference of the alignment cylinder 04 . However, departing from an ideal tangential arrangement, the alignment cylinder 04 may be slightly upwardly displaced, so that an alignment cylinder tangential plane 19 extends along the alignment cylinder 04 at a slight distance, for example 0.5 mm, above the surface 17 of the feed table 09 . It is achieved by this, as can be seen in particular in FIG. 3 , that a sheet 01 is slightly lifted in the contact area with the alignment cylinder 04 , so that an optimal placement of the sheet 01 on the circumference of the alignment cylinder 04 is possible, and the driving forces can be frictionally transferred to the sheet 01 from the alignment cylinder 04 over a contact surface of sufficient size.
As depicted in FIG. 3 , a suction element 21 is arranged on the inside of the suction roller 06 , which is a part of the alignment cylinder 04 . A suction chamber 22 is provided in the suction element 21 , and from which air is permanently generated and aspirated by the use of a vacuum source, which is not specifically represented, so that an underpressure or suction of 0.2 to 0.6 bar prevails in the suction chamber 22 . In the phase that is represented in FIG. 3 , the front edge 07 of the sheet 01 is already aligned in the correct position and rests against the front lay 08 . As soon as a recess 23 in the circumference of the suction roller 06 has reached the area above the suction chamber 22 , the underpressure or vacuum prevailing in the suction chamber 22 is transmitted into the recess 23 , so that the sheet 01 is frictionally fixed in place on the circumference of the suction roller 06 . The result of this is that, when the sheet is entering the contact area with the suction roller 06 , the sheet 01 is initially aligned by the front lays 08 in the correct position in respect to its front edge 07 , and subsequently is fixed in place on the suction roller 06 by the suction chamber 22 and by the recess 23 working together.
As can be seen in FIG. 1 , the sheets 01 essentially lie flat on the sheet level defined by the surface 17 of the feed table 09 during the entire time of their conveyance through the device 02 for the alignment of sheets in accordance with the present invention. Following the alignment of the front edge 07 of sheet 01 in the correct position, the sheet 01 is fixed in place in the device 02 by at least one of the vacuum receiving recesses 23 , which are provided, starting at the front lay 08 , one behind the other on the circumference of the suction roller 06 , so that the suction roller 06 is frictionally connected with the sheet 01 in rectangular contact areas and can drive the sheet 01 in the sheet conveying direction.
Following the alignment of the sheet front edge 07 , an offset of a lateral edge of the sheet 01 , in respect to a predetermined desired alignment, is measured by the use of a measuring device, which is not specifically represented. As a function of the result of the sheet lateral offset measurement, the sheet 01 is displaced transversely, in respect to the sheet conveying direction, until the sheet lateral edge extends along the desired alignment. For aligning the lateral edges of the sheets 01 , the alignment cylinder 04 can be axially displaced in the direction of its axis of rotation. In accordance with the representation in FIG. 1 , the alignment cylinder can be axially displaced out of, or into the drawing plane. To make this adjustment movement possible, the alignment cylinder, together with the drive shaft 05 , is fastened in a first frame element 24 , as seen in FIG. 1 , which, in turn, is axially seated in the direction of the axis of rotation of the alignment cylinder 04 on a second frame element 26 , which can be mounted fixed to a rack, as seen in FIG. 4 . For this purpose, the first frame element 24 can be embodied as a linear unit, which is seated in a rolling bearing, for example, and which can come into engagement with a prismatically configured linear guide 27 at the second frame element 26 .
The alignment cylinder 04 can be, and in particular together with the first displaceably seated frame element 24 , accelerated or braked linearly in the direction of the axis of rotation of the alignment cylinder 04 at a rate of up to +/−15 m/s 2 .
A transverse displacement device 32 for effecting the axial shifting of the alignment cylinder 04 is embodied in such a way that the alignment cylinder 04 can be linearly displaced, in particular together with the first displaceably seated frame element 24 , from a zero position through a distance of up to +/−8 mm, and in particular through a distance of up to +/−5 mm, in the direction of the axis of rotation of the alignment cylinder 04 .
The device 02 for the alignment of sheets is represented in FIG. 4 along the section line I—I of FIG. 1 . A total of six suction rollers 06 are arranged, fixed against relative rotation, on the drive shaft 05 for conveying the sheet 01 , which is located between the sheet hold-down roller 11 and the feed table 09 , in the conveying direction. The drive shaft 05 of the alignment cylinder 04 is rotatably seated on the first frame element 24 in bearing points 28 by schematically represented rolling bearings and can be rotatably driven by the operation of a drive shaft drive motor 29 . The drive motor 29 is also fastened on the first frame element 24 and also drives the sheet hold-down roller 11 via a gear 31 synchronously with the drive shaft 05 . The sheet hold-down roller 11 is also fastened on the first frame element 24 so that, as a result, the drive shaft 05 , together with the suction rollers 06 , the drive motor 29 , the gear 31 and the sheet hold-down roller 11 , can be linearly displaced by the linear movement of the first frame element 24 in the direction of the movement arrow 232 , i.e. in the direction of the axis of rotation of the drive shaft 05 , from a zero position in both directions. A motor, for example a linear motor 33 , whose linearly driveable power take-off shaft acts on the left end of the first frame element 24 , is fastened on the second frame element 26 and is usable for driving the first frame element 24 in the direction of the movement arrow 232 . Driven by the drive motor 33 , the first frame element 24 can be moved transversely in respect to the conveying direction of the sheets 01 , so that the lateral edge of the sheet 01 to be aligned can be aligned in the desired alignment as a function of the previously determined measurement result.
The drive motor 29 for the rotational driving of the drive shaft 05 can be controlled and regulated as a function of predetermined movement laws, and in particular as a function of the angle of rotation of the suction rollers 06 . It is thus possible to preset the acceleration, speed or the angle of rotation of the drive motor 29 for achieving desired movement kinematics, so that sheets of different lengths, in particular, can be conveyed by the use of identical suction rollers 06 and can be taken over, or passed on with the right alignment.
The front lays 08 on the circumference of the alignment cylinder 04 can preferably be accelerated or braked at a rate of up to +/−0.35 m/s 2 .
A second preferred embodiment of a device 40 for the alignment of sheets is represented in FIG. 5 . A total of four suction rollers 42 are fastened, spaced apart from each other, on a drive shaft 41 which is driven by a drive motor that is, not specifically represented. Two front lays 43 , which extend slightly above the surface 44 of the feed table 46 when the drive shaft 41 is in a corresponding position, are arranged on the circumference of each of the suction rollers 42 . To be able to frictionally fix the sheets 01 , by use of an underpressure or a vacuum, in the course of the sheets being conveyed in the device 40 , suction elements 47 are provided on the interior of each of the suction rollers 42 , and the suction rollers 42 are stationarily fastened on a first frame element 48 . The first frame element 48 is seated, in a manner corresponding to the first device 02 , linearly displaceable, on a second frame element 49 and can be driven transversely in respect to the conveying direction of the sheets 01 by operation of a drive motor 51 , as seen in FIG. 6 , but which is not represented in FIG. 5 . The power transmission from the drive motor 51 to the first frame element 48 takes place by use of a cam disk gear 52 shown in FIG. 5 , so that the first frame element 48 , together with the drive shaft 41 , the suction rollers 42 , the feed table 46 and a not specifically represented drive motor for the rotational driving of the drive shaft 51 , can be linearly driven transversely to the conveying direction of the sheets 01 out of a zero position in the direction shown by the movement arrow 53 .
The second embodiment of a device 40 for aligning sheets, in accordance with the present invention, is represented in cross section in FIG. 6 . A sheet hold-down roller 54 is arranged above the suction rollers 42 , and whose outer circumference is embodied to be helical, so that the gap between the sheet hold-down roller 54 and the suction rollers 42 is reduced or increased as a function of the angle of rotation of the front lays 43 . After fixing the sheets 01 in place on the suction rollers 43 , and during or after the alignment of the lateral edges of the sheets 01 , the sheets 01 are accelerated or braked, by an appropriate driving of the suction rollers 42 , in such a way that the sheets 01 can be transferred in correct alignment, to a downstream-located device 56 , for example a transfer roller 56 .
A sheet feeder 59 for use in conveying and aligning sheets 01 and having a device 02 , 40 for aligning sheets, in accordance with the present invention, is perspectively represented in FIG. 7 . An alignment cylinder 62 and a transfer cylinder 63 are arranged one behind the other in the conveying direction of the sheets 01 in a rack or frame 61 . The alignment cylinder 62 can be rotatably driven by a drive motor 65 , which can be regulated as a function of its angle. The alignment of the lateral edges of the sheets 01 can be measured by operation of a measuring device 64 , for example measuring heads 64 , which are arranged on an inlet side of the sheet feeder 59 . As a result, the sheet feeder 59 is used for aligning the sheets 01 in respect to their front edge 07 and lateral edge, and for accelerating the sheets 01 in order to be capable of transferring them, depending on their length, in correct alignment to the downstream-located transfer roller 63 .
The sheet feeder 59 is perspectively represented from the opposite side in FIG. 8 .
A section through the sheet feeder 59 depicted in FIGS. 7 and 8 is perspectively represented in FIG. 9 . The feed table 66 , on which the sheets 01 lie flat and are fed to the sheet feeder 59 in an overlapping manner, can be seen. The alignment cylinder 62 is again essentially composed of a drive shaft 67 and two suction rollers 68 fastened on the drive shaft. A plurality of recesses 76 , as seen in FIG. 10 , are arranged behind each other and next to each other, so that a sheet 01 can be aspirated by use of an underpressure or vacuum for being conveyed on the suction rollers 68 . It can be seen in FIGS. 9 and 10 that the recesses 76 start directly behind the front lays 69 and extend in the circumferential direction of the suction rollers 68 and are distributed over an angle of rotation area of approximately 200°. The result of this is that the sheets 01 can be frictionally fastened on the circumference of the suction rollers 68 , starting at 0°, which corresponds to the border of the front lay 69 , over an angle of rotation of the suction roller 68 of between 130° and 200°. Therefore, no special valve control, for turning the underpressure or vacuum on or off, is required. Instead, an underpressure or vacuum can be permanently applied to the suction chamber, because the sheets 01 are no longer automatically fixed in place on the suction rollers 68 at the time at which the angle of rotation area, which is embodied to be closed, of the suction rollers 68 is located above the suction chamber. The selection of the size of the angle of rotation area with the recesses 76 should be determined as a function of the sheet size to be processed. Holding elements 71 for use in fixing the sheets 01 in place after they have been transferred, are provided on the transfer roller 63 , which holding elements 71 fix the front edge of the sheets in place on the transfer roller 63 .
The alignment cylinder 62 is represented, removed from the sheet feeder 59 , in FIG. 10 . The drive shaft 67 is seated, at three bearing points 72 , on a first frame element 73 and can be driven rotatingly by a drive motor, which is not specifically represented, arranged at the end 74 of drive shaft 67 . The front lays 69 on the suction rollers 68 divide the circumference of the suction rollers 68 into a first area with recesses 76 , and a second area without recesses. The first frame element 73 is seated on the rack or frame 61 in sliding sleeves 77 and is linearly displaceable in the direction of the axis of rotation of the drive shaft 67 , and can be displaced transversely to the conveying direction of the sheets 01 by the use of a drive motor 78 .
The assignment of a sheet 01 to the alignment cylinder 62 , when a sheet feeder 59 is operated, is represented in FIG. 11 . First, the front edge 07 of the sheet 01 is aligned at the front lays 69 by the selection of appropriate relative speeds between the front edge 07 and the front lays 69 . Thereafter, the sheet 01 is fixed in place in the contact area between the suction rollers 68 and the underside of the sheet in that the recesses 76 reach the area above the suction chamber, which is charged with underpressure or vacuum. After the sheet 01 has been fixed in place, a relative movement transversely to the conveying direction between the sheet 01 and the alignment cylinder 62 is not possible. The entire first frame element 73 can be linearly displaced transversely to the sheet conveying direction 81 , in the direction indicated by the movement arrow 82 , for aligning one of the lateral edges 79 of the sheet 01 .
FIG. 12 shows the transfer roller 63 with holding elements 71 , a drive shaft 83 and a toothed drive wheel 84 . The transfer roller 63 is fastened to the rack 61 on both sides in bearings 86 .
A sheet guidance device 87 for use in the device 59 shown in FIGS. 7–9 , is represented by itself in FIG. 13 . The maximum distance between the sheets 01 and the surface of the feed table 66 is limited by hold-down plates 88 . In this case, the hold-down plates 88 can be oscillatingly lifted or lowered.
The alignment of a sheet 01 , in respect to its front edge 07 and in respect to its right lateral edge 79 and during the various phases of its conveyance on the alignment cylinder 62 , is represented in FIGS. 14 to 16 .
In the phase represented in FIG. 14 , the sheet 01 is conveyed in the conveying direction 81 at a conveying speed which is approximately 20% greater than the circumferential speed of the front lays 69 at the circumference of the suction rollers 68 .
Thereafter, and as represented in FIG. 15 , the front edge 07 of the sheet 01 comes to rest against the front lays 69 and in the process is braked to the circumferential speed of the suction rollers 68 . The front edge 07 is aligned at the front lays 69 within a short time by being braked, without the sheet 01 coming to a stop.
The sheet 01 has now been correctly aligned in respect to its front edge 07 . At this time, the recesses 76 at the suction rollers 68 , which cannot be seen underneath the sheet 01 , reach the area of underpressure or vacuum above the suction elements 47 . The sheet is aspirated onto the circumference of the alignment roller 68 and fixed in place by operation of this suction.
Following the alignment of the front edge 07 , the sheet 01 is conveyed on in the conveying direction 81 by the continued rotational drive of the suction rollers 68 . In the course of their conveyance by the suction rollers 68 , the sheets 01 also continue to remain flat on the feed table 66 , which is formed by a three-part plate 89 in the area above the suction rollers 68 , as seen in FIG. 16 . At about this time, the position of the sheet's right lateral edge 79 is measured by the non-represented measuring head 64 . At the same time, the motor 78 for driving the drive shaft 67 starts to accelerate in order to bring the sheets 01 up to the desired conveying speed in the conveying direction 81 .
Referring again to FIG. 16 , the location of the sheet 01 , in the course of a next phase of the conveyance, can be seen. It can be seen in FIG. 16 that the sheet front edge 07 has almost reached the rear edge of the plate 89 . In order to align the sheet lateral edge 79 in accordance with a desired position, the feed table 66 , together with the first frame element 73 located under it, the drive shaft 67 and the suction rollers 66 , has been displaced in the direction of the movement arrow 82 transversely in respect to the conveying direction 81 of the sheets 01 . The regulating distance 91 by which the sheet 01 , together with moved components, was displaced transversely to the conveying direction 81 in the direction of the axis of rotation of the drive shaft 67 , can be seen by the edge offset between the feed table 66 and the support surface 92 in the area of the transfer roller 63 .
In three diagrams, FIG. 17 depicts the path, speed and acceleration of the suction roller circumference in respect to an angle of rotation. In a first phase P 1 , the circumferential speed is maintained constant. During this phase P 1 , the front edges 07 of the sheets 01 come to rest against the front lays 69 and are aligned by means of this. At the end of phase P 1 , the sheet 01 is correctly aligned in respect to its front edge 07 and is fixed in place on the suction roller 68 by the application of an underpressure or vacuum.
In the following phase P 2 , the suction rollers 68 , and therefore the sheet 01 respectively adhering to them, are accelerated in such a way that, at the time of the sheet transfer to the downstream-located transfer cylinder 63 , the sheets 01 have a speed corresponding to the circumferential speed of the transfer cylinder 63 . This speed is again maintained constant in phase P 3 in order to allow a clean transfer of the sheets 01 to the transfer cylinder 63 . As soon as the sheets 01 are fixed in place on the transfer cylinder 63 , the sheets 01 are released from the suction roller 68 because no more recesses are provided on the circumference of the suction roller 63 at the corresponding angle of rotation. At approximately the same time of being driven in the conveying direction 81 , the sheets 01 are being moved transversely in respect to the conveying direction 81 during phases P 2 and P 3 for aligning a lateral edge 79 in respect to a desired direction. At the end of phase P 3 , the sheet 01 has been completely released from the suction rollers 68 and is now driven by the downstream-located transfer cylinder 63 . During the subsequent phase P 4 , the drive shaft 67 must be driven in such a way that the circumferential speed of the suction rollers 68 after a complete revolution, i.e. after 360°, again just corresponds to the feed speed of the sheets 01 out of the device for overlapping, such as the sheet feeder 59 . As can be seen from the acceleration, or speed diagram, it may be necessary, to accomplish this, to brake the suction rollers 68 down to the speed zero and to drive them opposite the direction of rotation required for conveying the sheets 01 . Departing from the greatest negative acceleration, the suction rollers 68 are then accelerated just enough, so that after a full revolution, the circumferential speed corresponds to the desired circumferential speed for a clean transfer of the sheets 01 from the device for overlapping, such as the sheet feeder 59 .
FIG. 18 shows the regulating distance, the speed and the acceleration of the suction roller 68 transversely in respect to the conveying direction 81 during one revolution. In this case, the diagrams are based on a maximum regulating distance of 5 mm, starting at the zero position. No transverse regulating movements are performed during a first phase Q 1 . In this first phase Q 1 , the position of the sheet lateral edge 79 to be aligned is measured by the measuring device 64 . In the subsequent phase Q 2 , the suction rollers 68 are accelerated transversely to the conveying direction 81 and are braked again thereafter, until the suction rollers 68 have traveled over a regulating distance of 5 mm, measured transversely to the conveying direction 81 of the sheets 01 . At the end of phase Q 2 , the actual position of the lateral edge 79 to be aligned corresponds to the desired alignment. In phase Q 3 which then follows, no further regulating movement of the sheet 01 transversely to the conveying direction of the sheets 01 takes place. In this third phase Q 3 , the sheets 01 can be transferred without problems to the downstream-arranged transfer cylinder 63 . In the following phase Q 4 , the suction rollers 68 , together with the drive shaft 67 , are driven in such a way that the zero position has again been achieved no later than after one revolution.
FIG. 19 depicts a device 101 which is usable for measuring the position of the lateral edge 79 of a sheet 01 , such as can be used, for example, in a sheet feeder 59 as represented in FIG. 7 . Two measuring heads 64 are provided in the device 101 , by use of which, the respective position of a lateral edge 79 of a sheet 01 can be determined. A correcting measurement signal, which can be evaluated in an installation control device, is issued by the measuring heads 64 as a function of the position of the lateral edge 79 . The lateral edge 79 of the sheet 01 to be measured must be arranged in such a way that the measuring heads 64 are positioned above and below the lateral edge 79 . The measurement itself is based on an optical system with the aid of light beams, such as described in EP 0 716 287 A2, for example. Of course any other measuring method or system, and in particular any contactless measuring method or system, can be used. In order to properly arrange the measuring heads 64 when processing sheets 01 of different widths, the measuring heads 64 are seated so that they are linearly displaceable along the position measuring device 101 in the direction indicated by the movement arrows 102 or 103 transversely to the conveying direction 81 of the sheets 01 . For this purpose, each of the measuring heads 64 is mounted on a carriage 104 , each of which can be displaced in a linear guide, not represented, between the plates 106 , 107 . In this case, the carriages 104 are driven via a drive arrangement, which is not specifically represented in FIG. 19 , by a drive motor 108 that is arranged underneath the plates 106 , 107 . To make possible a conveyance of the sheets 01 on the surface of the plates 106 , 107 which is as interference-free as possible, the gap between the plates 106 , 107 , which gap is required for the passage of the carriages 104 , is closed by a cover element 109 . In this case, the surface of the cover elements 109 extends on a level, namely the sheet level, as defined by the resting of the sheets 01 on the plates 106 , 107 in a flat, planar fashion.
FIG. 20 shows the lateral sheet edge position measured device 101 of FIG. 19 in a perspective view, taken from below. In this case, the drive motor 108 can be seen in particular, which drive motor 108 transfers regulating movements to two drive wheels 112 by use of a toothed belt 111 . A tensioning roller 113 is provided for tensioning the toothed belt 111 . Two toothed racks 114 are driven by the drive wheels 112 by use of two drive pinions 121 , as seen in FIG. 22 , which are connected, fixed against relative rotation, with the drive wheels 112 , but which drive pinions 121 are not represented in FIG. 20 , wherein both toothed racks 114 are each connected with a carriage 104 of a measuring head 64 . The drive wheels 112 and the drive pinions 121 connected with them are each fixed in place by a bracket 115 on the frames of the plates 106 or 107 .
FIG. 21 shows the sheet lateral edge position measuring device 101 in a side view from behind. The toothed racks 114 are fastened to the carriages 104 in such a way that the teeth mesh on respectively opposite sides of the drive pinions 121 , which are not represented in FIG. 21 . A linear regulating movement of the toothed belt 111 , for example in the directions indicated by the movement arrow 116 , causes oppositely directed regulating movements of the measuring heads 64 in accordance with the movement arrows 117 , 118 . Of course the same applies for an opposite regulating movement of the toothed belt 111 , because of which, the measuring heads 64 can be moved apart.
FIG. 22 shows the sheet lateral edge position measuring device 101 in a lateral plan view from one side. The carriage 104 is seated on the plates 106 , 107 and can be linearly displaced in linear guides 119 , which are formed by two grooves. The measuring head 64 , which is used as an electronic side marker, is fastened to the surface of the carriage 104 . The carriage 104 is driven by the toothed rack 114 , whose teeth mesh with a drive pinion 121 . The drive pinion 121 is, in turn connected, in a manner so that it is fixed against relative rotation, with the drive wheel 112 , which is driven by the drive motor 108 through the toothed belt 111 .
FIG. 23 represents a longitudinal section through the sheet lateral edge position measuring device 101 . The drive mechanism for the measuring heads 64 with the drive motor 108 , the toothed belt 111 , the drive wheels 112 , the drive pinion 121 and the laterally spaced, oppositely arranged, toothed racks 114 , can be seen once more. Moreover, in FIG. 23 a cover element 109 is represented, one of which cover elements 109 is associated with each of the respective measuring heads 64 . The cover elements 109 are embodied as links and are therefore elastically deformable in the direction of their longitudinal axis. An outer end of each of the cover elements 109 is fastened on a carriage 104 , so that these cover elements 109 can therefore be moved, together with the measuring head 64 , by operating the drive motor 108 . If the measuring heads 64 are moved out of their maximally distant position toward each other, it is necessary to deflect the cover elements 109 in a downward direction in sections out of the sheet level in which the flat-lying sheets 01 are conveyed. For this purpose, two holding plates 122 , 123 are provided for each of the two cover elements 109 in the device 101 , which two holding plates 122 , 123 are arranged opposite each other and are used as guide devices for each one of the cover elements 109 . Grooves 124 of complementary shape are cut into the inside surfaces of each of the holding plates 122 , 123 and extend in the shape of an arc of a circle downward, starting at the straight linear guide 119 . In the course of moving the oppositely-located carriages 104 toward each other, the cover elements 109 are downwardly deflected, so that because of this deflector, the cover elements 109 are either shortened or extended, depending on the position of the carriages 104 in the sheet level.
The arrangement for driving the measuring heads 64 by operation of the drive motor 108 is represented without the cover element and without the plates 106 or 107 in FIG. 24 .
FIGS. 25 to 27 show enlarged portions of the drive mechanism for the carriages 104 , or for the measuring heads 64 .
A coupling, consisting of coupling elements 130 , 131 , 144 , and which is usable for transmitting a driving torque to an axially adjustable shaft, such as drive shaft 67 shown in FIG. 9 , or its essential parts, is represented in FIGS. 28 to 31 . Such a coupling 130 , 131 , 144 can be used, in particular, for transmitting the driving torque from a drive motor to an axially adjustable alignment cylinder of a device for aligning sheet 02 , as seen in FIG. 1 , a device for aligning sheets 40 , as seen in FIG. 4 , or a sheet lateral edge position measuring device 101 . By employing such a coupling 130 , 131 , 144 it becomes possible to mount the drive motor for the rotational driving of the alignment cylinder stationarily, so that the mass which must be accelerated in the course of the regulating movement for aligning the sheet lateral edges 79 is reduced.
Essentially, the coupling 130 , 131 , 144 is composed of three coupling elements, which are individually represented in FIGS. 28 to 30 , respectively. The first coupling component is composed of two coupling elements 130 , as seen in FIGS. 28 and 131 , as seen in FIG. 29 . Each one of the two coupling elements 130 , 131 has recesses or apertures 132 , 133 , 134 , which are each slightly larger than the diameter of the associated shaft 67 , for example the drive shaft 67 of the alignment cylinder 62 . Feather key grooves 136 , 137 and 138 are provided on the inside of each of the recesses or apertures 132 , 133 , 134 , which key grooves 136 , 137 and 138 can be brought into engagement with a feather key element, which is not specifically represented, and which is arranged on the drive shaft 67 for transmitting a torque. The first coupling element 130 has a slit 139 for its stationary fixation, so that by tightening a straining screw which is, not specifically represented, in a threaded bore 141 , the first coupling element 130 can be frictionally fixed in place on the associated drive shaft 67 . As represented in FIG. 29 , the end of the second coupling element 131 , which is arranged on the associated drive shaft 67 , is embodied with two arms 142 and 143 , wherein the recesses or apertures 133 , 134 are applied aligned with each other on the arms 142 and 143 . The distance between the arms 142 and 143 has here been selected to be such that the plate-shaped first coupling element 130 can be arranged, free of axial play, with its end arranged on the drive shaft 67 between the arms 142 , 143 .
A second coupling component 144 is represented in FIG. 30 , and which can work together with the first coupling component 130 , 131 , that is composed of the coupling elements 130 and 131 , during the transmission of a torque. The third coupling element 144 has a bend, so that a radially outer end 146 of the third coupling element 144 projects past an end 147 of an associated shaft 148 . The third coupling element 144 is embodied to be fork-shaped on the side of the radially outer end 146 facing the first coupling component 130 , 131 , and extends with two arms 149 and 151 in the direction of the first coupling component 130 , 131 . Axial bearings 153 , in which the pivots of rolling bodies 154 , as seen in FIG. 31 , can be fastened, are attached to each of the arms 149 and 151 and also to an oppositely located counter-bearing 152 . In this case, the axial bearings 153 are arranged in such a way that pivots 156 extend parallel with outside portions 157 , 158 of the coupling elements 130 , 131 , which come into engagement with the rolling bodies 154 .
Functioning of the coupling 130 , 131 , 144 , comprised of the second coupling component 144 and the first coupling component 130 , 131 , put together from the coupling elements 130 and 131 , is explained by reference to FIG. 31 . After installation of the coupling elements 130 and 131 at the one shaft end, and of the third coupling element 144 at the oppositely located shaft end, the outsides 157 , 158 of the coupling elements 130 , 131 rest against the inside of the rolling bodies 154 . By tightening the straining screw at the coupling element 130 , the coupling element 130 is fixed in place and fixes the coupling element 131 axially on the shaft end because of its arrangement between the arms 142 and 143 . The feather key grooves 137 , 138 of the second coupling element 131 are made slightly wider than the feather key element of the drive shaft 67 , so that the second coupling element 131 can be slightly turned on the drive shaft 67 . A spring element 159 , which elastically braces the coupling element 131 against the coupling element 130 and which spreads the two coupling elements 130 or 131 open, is arranged between the radially outer ends 146 of the coupling elements 130 , 131 . A resilient, free-of-play seating of the outsides 157 or 158 at the rolling bodies 154 is assured at any time by this arrangement.
If now a torque is applied to the drive shaft 67 , or to one of the oppositely located drive shafts 67 , the torque is transmitted by a positive connection between the rolling bodies 154 and the outer ends of the coupling elements 130 and 131 . A deflection of the coupling 130 , 131 , 144 , in particular in the course of frequent changes of the direction of rotation, is prevented to a large extent because of the elastic bracing of the two coupling elements 130 and 131 .
If the drive shaft 67 , or one of the drive shafts 67 , is axially displaced in the direction of its axis of rotation in respect to the opposite shaft, the outsides 157 , 158 roll off on the rolling bodies 154 , so that an axial displacement, even under a load, is possible essentially free of resistance.
The employment of a coupling 130 , 131 , 144 with the coupling elements 130 and 131 , as well as the third coupling element 144 , in a sheet feeder 59 is represented in a view from above in FIGS. 32 and 33 .
In the phase represented in FIG. 32 , a sheet 01 has just arrived at the front lays 69 on the suction rollers 68 , so that the front edge 07 of the sheet 01 is aligned. In this phase, the feed table 66 which, together with the suction roller 68 and the drive shaft 67 , can be axially displaced in the direction of the axis of rotation of the drive shaft 67 , is in its zero position and can be displaced toward the right or the left in accordance with the movement arrow 161 by use of a linear drive, not represented in these drawings, but depicted and discussed in a prior section of the application.
The drive torque required for driving the drive shaft 67 , and therefore for conveying the sheets 01 , is generated by a drive motor 162 and is transmitted to the drive shaft 67 via the third coupling element 144 and the first and second coupling elements 130 or 131 .
The sheet position during a later process phase is represented in FIG. 33 , into which the sheet 01 has now been moved transversely to the conveying direction 81 for aligning one of its lateral edges 79 . In the representation of FIG. 33 , the required alignment movement is directed toward the right, which can be seen in particular from the edge offset 163 between the outer edge of the feed table 66 and the outer edge of the downstream-located device. The drive shaft 67 with the coupling elements 130 and 131 fastened thereon has also been axially displaced, together with the feed table 66 , in the direction of the axis of rotation of the drive shaft 67 .
In the course of the axially directed regulating movement for aligning the lateral edge 79 of the sheet 01 , the drive motor 162 was moved on by an angular amount of approximately 90° for conveying the sheet 01 in the conveying direction 81 . The compensation of the axial offset of the drive shaft 67 in relation to the drive motor 162 is made possible by the roll-off of the coupling elements 130 or 131 on the rolling bodies 154 .
While preferred embodiments of devices for aligning sheets, in accordance with the present invention, have been set forth fully and completely hereinabove, it will be apparent to one of skill in the art that various changes in, for example the type of press used to print the sheets, the specific nature of the downstream sheet handling or processing devices and the like could be made without departing from the true spirit and scope of the present invention which is accordingly to be limited only by the following claims. | The invention relates to devices for aligning sheets ( 1 ), which are overlapped with an offset and supplied to the device by a stream feeder and which can be transferred to a device ( 63 ) that is located downstream, after alignment of the front edge and one lateral edge of the sheets. At least pant of a sheet can be brought to rest on the periphery of an alignment cylinder ( 62 ), which is used to align the front edge of the sheet by means of front lay marks located on the periphery of said cylinder. At least one recess is provided on the periphery of the alignment cylinder, which, by the application of a negative pressure to said recess allows at least part of the sheet to be fixed by friction on the periphery of the alignment cylinder, in such a way that in the contact zone, drive forces from said cylinder can be transferred by friction to the sheet. A measuring device ( 64 ) determines the offset of a lateral edge of the sheet in relation to a predetermined set alignment. A transversal displacement device is used to align a lateral edge of the sheet in accordance with the measurement result of the measuring device. The acceleration and/or speed and/or angle of rotation of the drive motor for driving the rotation of the alignment cylinder can be controlled or adjusted according to predetermined laws of motion, in particular in accordance with the angle of rotation of the alignment cylinder. | 1 |
BACKGROUND OF THE INVENTION
The field of the present invention relates to building materials and particularly to “green” building blocks made from culm such as residual rice straw, a by-product of the rice growing industry.
Providing affordable housing while decreasing air pollution is an ideal worth fighting for. Housing is typically considered by most not to be affordable due, in part, to the high cost of the building materials. Conventional building materials, such as lumber, are costly because they are becoming more and more scarce as the demand for more and more housing increases to meet the needs of the world's burgeoning population. In addition, when the trees are cut down to make the lumber to build the house, the result is an adverse effect on our air quality as these natural resources are no longer able to turn carbon dioxide into oxygen.
In an effort to find alternative building materials, people have been turning to recycled goods and/or the by-products of an industry. One such source has been culm, commonly referred to as straw, which is what is left over when grains, such as wheat, rice, barley, oats, and rye, are harvested. Straw is a viable building material because it is plentiful and inexpensive. Buildings built with straw bales have well-insulated walls, simple construction, and low costs. Moreover, in many areas, straw is still burned in fields, producing significant air pollution. For example, in California more than one million tons of rice straw were burned each fall in the early 1990's, generating an estimated 56,000 tons of carbon monoxide annually, which is approximately twice that produced from all of the state's power plants. By converting an agricultural by-product into a valued building material, another benefit to the community is therefore a reduction in air pollution.
A number of drawbacks exist to the use of straw as a building material. Straw does not have the same structural integrity as wood, cement, or other conventional building materials. As a consequence, straw does not have the load bearing capacity that so many architects, engineers, and contractors require. Straw is also highly susceptible to moisture and can and will rot if there is too much exposure to moisture over time. Moreover, straw bales are of an inconsistent quality. They are also not sized to building industry standards.
FIG. 5 is illustrative of some of these points. Shown there are two differently sized conventional straw bales, namely, a 3-tie straw bale on the left and a 2-tie straw bale on the right. The denomination of “3-tie” or “2-tie” is due to the number of ties T being wrapped about the straw stalks S, as seen in FIG. 5 . The larger 3-tie bale is typically 32″ to 47″ long by 23″ to 24″ wide by 14″ to 17″ high. The dimensions of a 2-tie bale are similarly varied and are typically in the range of 35″ to 40″ long by 18″ wide by 14″ high. A conventional concrete or cinder building block, however, is typically 24″ long by 12″ wide by 12″ high. The weight of a 3-tie bal can be anywhere between 75 to 100 lbs., whereas a 2-tie bale is typically 50 lbs. OSHA product weight requirements, however, require less than 50 lbs. per block, with 40 lbs. typically being an acceptable weight that can be handled by one person.
FIG. 5 illustrates that the straw stalks S of a conventional straw bale appear to be aligned parallel to a single axis of alignment, A w . The appearance of alignment occurs because of the cut, rake, and bale process of making the bale. There are no machines or modifications of machines that intentionally align the straw to make specific straw-aligned bales. The general alignment A w of the straw S can be described as “horizontally aligned”, i.e., horizontal or parallel to the ground G when the bale is laid flat. The general alignment A w can also be described as running parallel to the width W axis and perpendicular to the length L and height H axes or, alternatively, parallel to the plane defined by the top or bottom walls (the intersection of the L and W axes).
It is the inventors' understanding that those skilled in the art prefer “horizontal alignment” to increase the load bearing capacity of each bale. Gleaned from compression tests of individual bales, the prior art teaches that flat bales can carry far more load than bales stacked on edge. Flat bales failed at an average load of 10,000 lb/ft 2 (48,800 kg/m2); on edge, bales failed at an average of 2,770 lb/ft 2 (13,500 kg/m 2 ). To further increase the load bearing capacity of the bale other than laying it flat, the prior art also teaches the use of threaded rods that may be inserted through each bale or framed around each bale and then bolted through a wide top plate and tightened down after the roof is installed. Pre-compressing the walls in this manner minimizes further settling after the roof is installed.
FIG. 5 also illustrates how conventional prior art straw bales do not have a smooth cut surface and the corners are rounded, i.e., the edges are not crisp and the corners are not square. What FIG. 5 does not illustrate is the high level of susceptibility to moisture damage that straw has or the inconsistent and often poor quality of the traditional straw bale itself.
A “green” building material such as a culm or straw block that has an increased load bearing capacity over traditional straw bales, is of a consistent quality, is sized for building industry standards, and has an increased resistance to water damage is therefore desired.
SUMMARY OF THE INVENTION
Having recognized these conditions, the present invention is directed to a culm block comprising a plurality of straw stalks that are “vertically aligned”, i.e., perpendicular to the ground when the block is laid flat. Vertically alignment, the inventors surprisingly discovered, advantageously provides for at least 25% greater load bearing capacity compared to conventional horizontally aligned bales. Vertical alignment also advantageously provides for increased insulating values, as well as a smooth cut surface. By vertically aligning the straw, the culm block of the present invention also advantageously has a consistent shape, with square corners and crisp edges.
Another related aspect of the invention is to provide a culm block that is properly sized for building industry standards.
The culm block may also be treated with a binder and a moisture inhibitor to further increase the block's quality, structural integrity, and resistance to moisture damage.
The culm block may optionally include a pair of throughholes drilled through the top and bottom walls. The holes may be used to tie the blocks to the foundation and thereby ultimately increase the shear integrity of the wall system.
In a similar manner, the culm block may include a lath or external strapping sleeve for added structural support. Prior to the addition of the lath, the culm block may be mill finished to further increase its quality and consistency.
Another aspect of the present invention is a method for forming the novel culm block that may include sorting the stalks according to length, checking the stalks for moisture content, and drying the stalks depending upon their moisture content prior to compression and formation. Other and further objects and advantages will appear hereinafter.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a culm block according to a preferred embodiment;
FIG. 2 is another perspective view of the culm block shown in FIG. 1 ;
FIG. 3 is a cross-sectional view taken along line 3 — 3 shown in FIG. 1 ;
FIG. 4 is a flow chart illustrating a preferred method of manufacturing the culm block shown in FIG. 1 ; and
FIG. 5 illustrates the prior art.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
Preferred embodiments will now be described with reference to the drawings. For clarity of description, any element numeral in one figure will represent the same element if used in any other figure.
FIGS. 1-3 illustrate a culm block 10 comprised of a plurality of adjacent stalks 12 substantially aligned parallel to one another and formed to define the building block 10 . The stalks 12 may be wheat, rice, barley, oats, or rye straw. Rice straw is preferred due to its extremely high silica content and therefore inherent fire retardant properties. Moreover, rice straw is typically weed and pest free.
The block 10 has a top wall 14 and an opposing bottom wall 16 , a front wall 18 and an opposing rear wall 20 , and first and second opposed sidewalls 22 . A lath 24 is seen disposed about the front and rear walls 18 , 20 and sidewalls 22 . The lath 24 may be described as a sleeve that is wrapped about the block 10 .
The lath 24 provides increased structural support to the block 10 . Such a feature is particularly advantageous when one considers that a traditional bale typically only has two or three ties usually made of twine for support, such as the ties T illustrated in FIG. 5 . Because of such a lack of support, conventional bales can easily fall apart or bulge under their own weight. The lath or wire mesh banding 24 around block 10 girdles it and advantageously provides resistance to the straw stalks 12 from bulging. In addition, the lath 24 also provides an additional option for an anchoring system. In particular, the lath 24 acts as stucco wire and will make the construction process with the block 10 faster than conventional bales. Conventional bales require the stapling of stucco wire on the side of the straw bale wall in order to provide an adequate structural matrix for the stucco. This process is eliminated with the novel block 10 .
The lath 24 may be comprised of completely recycled material such as recycled steel or plastic. If steel is used, it is preferably galvanized and more preferably galvanized and coated.
Turning to FIGS. 1 and 2 , the top wall 14 and bottom wall 16 define a pair of holes 25 therethrough. Tubing 26 , which may be made from recycled plastic, may be inserted into each hole 25 . The holes 25 , either with or without tubing 26 , may be included in block 10 to offer an optional alignment and anchoring system. If employed, the holes 25 are preferably 2½″ in diameter. Structural steel reinforcing may be inserted through each hole 25 and set with a concrete grout, for example. The pre-drilled holes 25 , when filled with concrete and steel, help to tie the blocks to the foundation, ultimately increasing the shear integrity of the wall system.
FIGS. 1 and 2 illustrate a block 10 that is sized to a building industry standard, namely, 24″ long by 12″ wide by 12″ high. Accordingly, the block 10 illustrated in FIGS. 1 and 2 is rectangular in shape. Other dimensions may also be employed as long as they are standardized building sizes. Unlike traditional bales that are odd-sized, such as a 3-tie bale that may be 40″ long by 22″ wide by 16″ high, the block 10 is a size that a builder can utilize consistent with existing building techniques developed for concrete blocks. Consequently, block 10 is easily adapted to current construction techniques; it easily integrates with traditional 4′ by 8′ construction modules; and it requires less space in the floor plan when compared to the larger footprint of a traditional straw bale wall.
As shown in FIGS. 1 and 2 , the block 10 preferably weighs under 40 lbs. With this light weight, one person can handle the block 10 . This weight is also within the OSHA product weight requirements, unlike traditional bales that may weigh up to 75 to 100 lbs., which weight requires two or more persons for moving and constructing.
As best seen in FIG. 3 , the stalks 12 of the culm block 10 are “vertically aligned”, i.e., they are perpendicular to the ground G when the block 10 is laid flat. The axis of alignment A H of the straws 12 is therefore preferably orthogonal to the plane defined by the top and bottom walls 14 , 16 (the intersection of the L and W axes). As seen in FIG. 3 , the axis of alignment AH runs orthogonal to the width W and length L axes and parallel to the height H axis or, alternatively, orthogonal to the plane defined by the ground G.
Contrary to the teachings of the prior art, vertically alignment provides for at least 25% greater load bearing capacity compared to conventional non-aligned or potentially “horizontally aligned” bales. Vertical alignment also advantageously provides for increased insulating values, possibly R-28 or higher, because horizontally placed straw of traditional bales acts like a wick, thus increasing the conductance (U-value) of the material and undesirably allowing for greater thermal transmission. Vertical alignment also provides for a smooth cut surface. By vertically aligning the stalks 12 , the culm block 10 of the present invention has a consistent shape, with square corners and crisp edges. This makes the construction of buildings much more efficient when compared to traditional rounded corner straw bales.
Turning to FIG. 4 , a method of forming the novel block illustrated in FIGS. 1-3 is disclosed. As shown there, the first step is “Harvest straw from field” at step 28 . After harvesting, the straw then needs to be transported to the processing facility as shown at step 30 . Once at the processing facility, the straw is unloaded at step 32 , preferably via a hydraulic squeeze lift, and then loaded into an apparatus to remove the ties T (as shown in FIG. 5 ). The apparatus is preferably a Hunterwood 3-tie de-stacker. Once loaded into the de-stacker, the straw is moved down a conveying system to a twine saw. When the twine hits the twine saw, the bale ties are removed at step 34 . The next step, step 36 , is entitled “Treat straw with a non-toxic moisture inhibitor and/or binder.”
At step 36 , a moisture inhibitor and/or a binder is disposed on or integrated into the straw 12 . Step 36 ensures that the block 10 , when delivered, has a consistent quality. Current bales, such as those illustrated in FIG. 5 , have high fluctuations in sizes, typically up to five inches, and a wide range in moisture content, typically between 10 to 25%. High moisture is the weakness and largest concern for builders interested in integrating straw building materials into their work. Straw will not rot at a moisture content of 14% or less. For this reason, the block 10 preferably has a predetermined moisture content not to exceed 14%. To ensure this, a drier system is part of the manufacturing process, as illustrated in FIG. 4 at step 42 .
The binder and moisture inhibitor are both preferably environmentally friendly and non-toxic. When treated with the binder, the structural integrity of the block 10 should be increased without decreasing the insulating properties of the block 10 . In a similar manner, when the stalks 12 are treated with the moisture inhibitor, the block's resistance to moisture is increased without decreasing the insulating properties of the block 10 . Accordingly, the binder may be selected from the group consisting of aluminum hydroxide, magnesium hydroxide, clay, kaolin, bitumen, and most preferably borax (a natural product composed of hydrated sodium borate, sometimes referred to as or including sodium borate decahydrate, sodium diborate, tincal, tincalconite, tincar, hydrated sodium boration, sodium tetraborate, rasorite, or Sporax®). The moisture inhibitor may be selected from the group consisting of paraffin wax, silica gel (a non-toxic, non-corrosive form of silicon dioxide synthesized from sodium silicate and sulfuric acid and processed into granular or beaded form), molecular sieve (a uniform network of crystalline pores and empty adsorption cavities derived from sodium, potassium or calcium crystalline hydrated aluminosilicates), activated clay (a layered structure of activated (bentonite) clay that is a naturally occurring, non-hazardous and salt-free substance), bitumen, and most preferably borax.
Referring again to FIG. 4 , the next step in the process is step 38 entitled “Align and sort straw.” Here, the stalks 12 are intentionally aligned substantially parallel and most preferably parallel to one another. The stalks 12 are also preferably sorted according to length, wherein stalks 12 of substantially identical length are grouped together. After the stalks 12 are aligned and sorted together and step 38 , the moisture content of the stalks 12 is then checked at step 40 . The stalks 12 are dried via a drier system dependent upon the moisture content at step 42 . The stalks 12 are preferably dried to a moisture content not to exceed 14%, as straw will not rot at a moisture content of 14% or less.
After the stalks 12 are dried to the preferred moisture content of 14% or less, the stalks 12 are compressed and formed into standardized building blocks wherein the stalks 12 are vertically aligned or, stated otherwise, perpendicular to the ground when the block is laid flat, as shown in FIG. 4 at step 44 and, regarding the vertical alignment, as best seen in FIG. 3 . For compressing and forming the stalks 12 into the block shape, the stalks 12 are preferably fed into a Hunter Wood fc8310 series forage compactor. Once compacted, the block 10 exits the compression chamber and is sleeved with a lath, preferably comprised of recyclable galvanized steel and coated at step 46 . The block 10 then exits the conveyor, is palletized, stretch-wrapped, pallet bar coded, and ready for shipping or storage.
Prior to the addition of the lath, such as lath 24 illustrated in FIGS. 1 and 2 , the culm block 10 may be mill finished to further increase its quality and consistency. Where the optional throughholes, such as holes 25 illustrated in FIGS. 1 and 2 , are desired, the holes may be drilled before or after step 46 , but are preferably drilled before step 46 . Tubing 26 may also be inserted into each hole 25 at this time. The pre-drilled holes 25 , when filled with concrete and steel, help to tie the blocks 10 to the foundation, ultimately increasing the shear integrity of the wall system.
Thus, while embodiments and applications of the novel culm block and method for making the culm block have been shown and described, it would be apparent to one skilled in the art that other modifications are possible without departing from the inventive concepts herein. The invention, therefore, is not to be restricted except in the spirit of the claims that follow. | A culm block and a method of manufacture are disclosed. The culm block comprises a plurality of straw stalks that are “vertically aligned”, i.e., perpendicular to the ground when the block is laid flat. The straw is treated with a moisture inhibitor and/or a binder. Throughholes, which may have tubes associated therewith, are formed into the top and bottom walls of the culm block. A lath or external strapping sleeve is wrapped about the front, rear, and side walls of the block for added structural support. The method of manufacture may include sorting the stalks according to length, checking the stalks for moisture content, and drying the stalks depending upon their moisture content prior to compression and formation. | 4 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a Continuation-In-Part of U.S. Ser. No. 29/358,982 filed 2 Apr. 2010 entitled CROWN MOLDING SUPPORT TOOL.
BACKGROUND
[0002] 1. Field of the Invention
[0003] The present disclosure is directed generally to an apparatus for supporting a molding piece or similar element against a wall surface during installation of the molding piece, and more particularly, to an adjustable apparatus that supports and positions various sizes and configurations of molding pieces against a wall surface enabling a single installer to install a molding piece against a wall surface at a desired position.
[0004] 2. Description of the Related Art
[0005] Crown molding serves several important aesthetic and utilitarian functions, including the obscuring of the rough and abrupt intersection of a ceiling and wall, the general enhancement and refinement of the decor and design of a room, and the stabilization of some wall coverings where they intersect with a ceiling. However, because of the inherently elevated, overhead location of crown molding, installation can be cumbersome and difficult, and often requiring the cooperation of two or more workers due particularly to the length of crown molding to be installed. The prior art U.S. Pat. No. 7,603,817 (incorporated herein by reference for background information) accomplishes this task well, but it creates a fixed support “box” region (encapsulated space in the '817 patent) which the molding must fit within regardless of its shape and cross section. For example, small moldings would benefit from the box space (ie the confined space between arms of the support which form a box area with the wall) should be as small as possible, whereas a larger molding needs more box space. This prior art device cannot fully manage this problem.
BRIEF SUMMARY OF THE DISCLOSURE
[0006] As stated there is an apparatus and method for supporting a workpiece against a wall (wall or ceiling surface) in order to further mount the workpiece, typically on the wall or ceiling. This helping tool allows a single person to hold a workpiece in place(s) at an elevation while working on final installation. The disclosure includes a knuckle member which at least two generally orthogonal passages therethrough which receive bars having wall pads. The bars can be positionally adjusted within the passageways to preferably create the appropriate shaped “box” enclosure to hold the workpiece. The preferred shape enclosure is the smallest which will hold the piece the closest to the wall surface while being adjustable for different sized workpieces.
[0007] Also disclosed is an improvement to an apparatus for supporting an elongated workpiece element against at least a wall surface at a distance from a floor surface, the apparatus having a handle having opposing first and second ends; a head assembly coupled to the first end of the handle, the head assembly being configured to support and surround a portion of the workpiece at a prescribed distance from said floor surface when said second end of said elongate body portion is adjacent said floor surface and said first end is adjacent said at least a wall, the improvement having a knuckle member, having at least two orthogonal passages there through, a pair of wall pads, configured to engage a wall; a pair of bars extended from the wall pads with at least a portion of which is sized to be slideably received within said passages; engagement members coupled to said knuckle member for engaging said bars to prevent movement of said bars within said knuckle when user-adjusted to a selected position; thereby creating user definable sides of a box area formed against wall surfaces.
[0008] Also disclosed is an apparatus, wherein said bars have a non-circular cross section, so that when inserted into said passages, they are prevented from rotating therein.
[0009] Also disclosed is an apparatus, wherein the pads include a high friction surface on their exterior face to engage wall surfaces without slippage.
[0010] Also disclosed is an apparatus, wherein the knuckle member includes rectangular passages sized to slideably receive said bars, and wherein said knuckle further includes at least one set screw positioned to engaged the passages and hence the bars to fix there position when the set screws are engaged on into the bars.
[0011] Also disclosed is an apparatus, wherein the knuckle further includes a pivot flange extending orthogonally from a surfaces thereof, said pivot flange being connected to the handle in such a way as to allow pivoting of the knuckle relative to the handle.
[0012] Also disclosed is an apparatus, wherein the knuckle includes two non-intersecting through-going passages.
[0013] Also disclosed is an apparatus, wherein the passages are square the bars have a square cross section.
[0014] Also disclosed is an apparatus, wherein the passages are non-circular and the bars have a like cross section.
[0015] Also disclosed is an apparatus, wherein the bars are fully removable from the passages and replaceable with alternative bars.
[0016] Also disclosed is an apparatus, for supporting an elongated workpiece element against at least a wall surface at a distance from a floor surface, the apparatus comprising: a handle having opposing first and second ends; the head assembly coupled to the first end of the handle, the head assembly being configured to support and surround portion of the workpiece at a prescribed distance from said floor surface when said second end of said elongate body portion is adjacent said floor surface and said first end is adjacent said at least a wall, the head having a knuckle member, having at least two through-going passages therethrough a pair of wall pads, configured to engage a wall; a pair of bars extended from the wall pads with at least a portion of which is sized to be slideably received within said passages, engagement members coupled to said knuckle member for engaging said bars to prevent movement of said bars within said knuckle when user-adjusted to a selected position, thereby creating user definable sides of a box area formed against wall surfaces.
[0017] Also disclosed is a method temporarily and adjustably maintaining an elongated workpiece adjacent a wall surface to allow further installation of the workpiece on the wall surface, comprising the steps of:
a. creating a box enclosure area around a portion of the workpiece, the box being formed of two adjacent generally orthogonal sidewalls, first and second wall pads with first and second bars orthogonal to each other and extending from the pads; b. receiving the bars within the knuckle member having through going passages for receiving the bars and maintaining in a generally orthogonal orientation to each other; c. adjusting the length of said first and second bars within the knuckle passageways to create a rectangular box enclosure area of preferred shape to maintain said workpiece close to the wall surface.
[0021] Also disclosed is a method wherein the step of adjusting the length of said bars includes sliding said bars within the passageway to form a preferred rectangular enclosure and then locking the bars from movement with the passageways.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0022] FIG. 1 is a perspective view of one aspect of the invention.
[0023] FIG. 2 is a side plan of the embodiment in FIG. 1 .
[0024] FIG. 3 is a side plan, rotated 90 degrees of the embodiment in FIG. 2 .
[0025] FIG. 4 is a top plan of the embodiment in FIG. 1 .
[0026] FIG. 5 is a rear plan of the embodiment in FIG. 1 .
[0027] FIG. 6 is a bottom plan of the embodiment in FIG. 1 .
[0028] FIG. 7 is a perspective of the knuckle portion of the embodiment in FIG. 1 .
[0029] FIG. 8 is a top plan view of the knuckle portion of the embodiment in FIG. 1 .
[0030] FIG. 9 is a side plan view of the knuckle portion of the embodiment in FIG. 1 .
[0031] FIG. 10 is a bottom plan view of the knuckle portion of the embodiment in FIG. 1 .
[0032] FIG. 11 is the other side plan view of the knuckle portion of the embodiment in FIG. 9 .
[0033] FIG. 12 is a view like FIG. 11 but rotated 90 degrees.
[0034] FIG. 13 is a view like FIG. 11 but rotated 180 degrees.
DETAILED DESCRIPTION
[0035] Installation of longitudinal members at or near ceiling heights can be difficult, especially if one is working alone. Crown moldings are one type of product which falls into this category. Pipes, cables and other elements which must be mounted at heights create similar challenges. For convenience, reference will be made to workpieces or crown moldings, but it is intended that other product installations are defined to fall under nomenclature. Likewise, reference will be made to walls or ceilings. They should be considered interchangeable and may be referred to as just wall surfaces.
[0036] Crown molding serves several important aesthetic and utilitarian functions, including the obscuring of the rough and abrupt intersection of a ceiling and wall, the general enhancement and refinement of the decor and design of a room, and the stabilization of some wall coverings where they intersect with a ceiling. However, because of the inherently elevated, overhead location of crown molding, installation can be cumbersome and difficult, and often requiring the cooperation of two or more workers due particularly to the length of crown molding to be installed.
[0037] However, two or more workers are often not available or free to assist in the installation of a crown molding piece, which thus causes delays in the installation of the crown molding, or perhaps even causing a user to forego installing crown molding due to the unavailability of an assistant, which is often the scenario for a homeowner.
[0038] The present disclosure in an improvement over the prior art device disclosed in U.S. Pat. No. 7,603,817 to Lewis which discloses an apparatus for supporting a molding article/workpiece while the molding article is positioned for mounting and a method of temporarily and adjustably maintaining an elongated workpiece adjacent to a wall surface to allow further installation of the workpiece on the wall surface.
[0039] With reference to FIG. 1 , the apparatus is designated generally by reference numeral 10 . Apparatus 10 generally includes an extendable elongate body member/handle 12 preferably pivotally coupled to a head member 14 . With particular reference now to the body member 12 . The function of the handle 12 is similar to that disclosed in the above '817 patent to Lewis.
[0040] With specific reference now to FIGS. 1-6 the head assembly 14 of apparatus 10 will now be described. Head assembly 14 is pivotally connected to a aforesaid head-cap assembly 30 preferably via a conventional pin assembly 35 . Head assembly preferably pivots about 180 degrees of rotation relative to end cap 30 . Head assembly 14 includes a knuckle block member 40 (shown in detail in FIGS. 7-13 ) that pivotally connects to the end-cap assembly 30 , via the pin assembly 35 .
[0041] The knuckle 40 includes at least two passages 42 , 44 therethrough, the passages being preferably oriented orthogonally to each other. The passages a sized to sideably receive wall contact arms 50 , 52 which themselves preferably include contact pads 54 , 56 which extend generally and preferably orthogonally from support bars 58 , 60 which may be also be pivotally attached to pads 54 , 56 for additional flexibility on wall surfaces which are not at right angles or curved surfaces. Preferably the bars are fully removeable so that they can be swapped out with other bars/pads of different shape/size or attachment fixture. For example a further set of bars/pads which are longer. shorter, of different lengths, will accommodate larger or small confined spaces (boxed area) without excessive protrusion of the bars thru the passages and knuckle.
[0042] Bar 58 , 60 are sized to be slideably received into passages 42 , 44 with their position being fixable by clamping mechanisms or engagement members, such as the set screws 62 , 64 . Preferably they have the same cross sectional shape as the passages, though small enough to be received therein but preferably not rotational.
[0043] FIG. 3 shows one embodiment pads affixed to bars 58 , 60 offset maximally to the right, out outside the “box” area which is defined by the two bars and the two wall portions (not shown) which created a confined area which will maintain the crown molding (or other element) bound therewithin. By offsetting the pads/feet maximally outside the box area, they will not interfere with any portion of the molding that might otherwise fit.
[0044] Knuckle 40 therefore makes it possible to define a box area of any rectangular shape according to accommodate molding or other elements to be attached to the wall require. For example, if an element to be attached, such as cable raceway, which has a greater extent in the horizontal direction than vertically, the length of the bars within the knuckle can be adjusted to suite.
[0045] It is advantageous to configure the lengths of the bars to minimize the box size since assists in maintaining the element/crown molding closer to the wall surfaces so that attachment is as small as possible.
[0046] FIGS. 7-13 illustrate knuckle 40 alone. Passages 42 , 44 are offset from each other in the same horizontal plane, but the can also be stacked in the same or different vertical plan. They may have a rectangular or square cross section or preferably a non-circular cross section to prevent rotation. Circular is also possible.
[0047] To accommodate pivoting of the handle 12 on pivot 35 , on the knuckle 40 , a pivot flange 70 extends preferably orthogonally from the body of the knuckle. The flange includes an aperture 72 , to receive pivot 72 .
[0048] Other than indicated above, the shape of the knuckle 40 is dictated by aesthetics rather than function.
[0049] If only a sidewall is involved, such as shown in FIG. 6 of U.S. Pat. No. 7,603,817, the present disclosure envisions this option by either mounting one of pads 54 , 56 on a 90-180 degree pivot or providing an alternate configuration with both pads having the same/parallel orientation.
[0050] Also disclosed is a method of temporarily and adjustably maintaining an elongated workpiece adjacent a wall surface to allow further installation of the workpiece on the wall surface, having one or more of the following steps: creating a box enclosure area around a portion of the workpiece, the box being formed of two adjacent generally orthogonal existing walls (such as a wall and a ceiling or two wall surfaces, bounding the sidewall(s) by first and second wall pads with first and second bars orthogonal extending from the pads; receiving the bars within the central point of convergence/knuckle member having through going passages for receiving the bars and maintaining in a generally orthogonal orientation to each other; adjusting the length of said first and second bars within the knuckle passageways to create a rectangular box enclosure area of a shape preferred by the user to maintain said workpiece close to the wall surface. The box enclosure being the contiguous structure of the wall(s), the bars and knuckle, which defines an enclosed spaced. The method preferably teaches adjustment of the confined space (box) to include the shape thereof is preferred for maintaining the workpiece and then locking the position of the bars in the knuckle to maintain the space.
[0051] The method further includes the step of adjusting the length of said bars includes sliding said bars within the passageway to form a preferred rectangular enclosure and then locking the bars from movement with the passageways.
[0052] The method further includes the step of swapping the bars/pads for bars/pads of different length to achieve different size box areas.
[0053] The description of the invention and its applications as set forth herein is illustrative and is not intended to limit the scope of the invention. Variations and modifications of the embodiments disclosed herein are possible, and practical alternatives to and equivalents of the various elements of the embodiments would be understood to those of ordinary skill in the art upon study of this patent document. These and other variations and modifications of the embodiments disclosed herein may be made without departing from the scope and spirit of the invention. | An apparatus and method for supporting a workpiece against a wall (wall or ceiling surface) in order to further mount the workpiece, typically on the wall or ceiling. This helping tool allows a single person to hold a workpiece in place(s) at an elevation while working on final installation. The disclosure includes a knuckle member which at least two generally orthogonal passages therethrough which receive bars having wall pads. The bars can be positionally adjusted within the passageways to preferably create the appropriate shaped “box” enclosure to hold the workpiece. The preferred shape enclosure is the smallest which will hold the piece the closest to the wall surface while being adjustable for different sized workpieces. | 4 |
This application is a division of 07/787,737, filed Nov. 4, 1991, now U.S. Pat. No. 5,118,042, which was a continuation of 07/659,446, filed Feb. 22, 1991, now abandoned, which was a continuation of 07/371,101, filed Jun. 26, 1989, now abandoned.
BACKGROUND OF THE INVENTION
This invention relates to a multiple chamber hose suitable for drip irrigation and the like, and to a method of making such a hose.
Drip irrigation hose has been formed from continuous plastic strips for a considerable period of time, and there is a wide range of prior patents in the field. The most pertinent of these known to applicants are listed in the attached Information Disclosure Statement.
The various prior art hoses operate in the same general manner. A primary chamber is connected to the water supply, and the pressure in the primary chamber is relatively high. Some form of flow restriction devices are incorporated in or added to the hose for distributing water at spaced locations along the hose at a substantially reduced pressure. One problem in the manufacture and use of such hose is achieving and maintaining a desired stable low rate of flow from the restriction devices. Such irrigation hose is manufactured in rolls and is installed in very long lengths, with typical roll lengths in the range of 3,000 to 15,000 feet. Uniformity in the construction of the restriction device over thousands and thousands of feet of hose at high speeds has been difficult.
Another problem encountered with irrigation hose is the cost of manufacture, since large quantities of the hose are utilized and typically must be replaced every growing season. Therefore a design and method of manufacture which permits high speed production while at the same time maintaining precise control of the restriction devices is highly desirable.
Accordingly, it is an object of the present invention to provide a new and improved multiple chamber hose and a method of making such a hose which is less expensive, more accurate, and more reliable than present hose.
Another problem with many present manufacturing methods is that they require molding of plastic to establish the restricted flow paths. This usually is performed by melting plastic resins and forming the entire tube or by forming the secondary flow path from molten plastic and adding it to the cured plastic film while still in a semi-moltent stage. The cured film forms the main body of the tube. See for example the U.S. Pat. Nos. to Chapin, 4,534,515 and 4,572,756, and Mock 3,903,929. The above mentioned techniques are limited in rate of production due to the molten nature of the material and the necessary cure time. Uniformity of the restricting secondary chamber is an important consideration in hose manufacture because of its effect on uniform flow rates desired for the finished product in the field. In contrast the precision die cutting of the secondary chamber in the present invention provides exact repeatability with high rates of production. Further, deformation of the tube forming material with its accompanying uniformity problems is not required.
Other objects, advantages, features and results will more fully appear in the course of the description.
SUMMARY OF THE INVENTION
A multiple chamber hose for drip irrigation and the like having a primary chamber for fluid flow therethrough and a multiple layer section with a primary layer, a mid layer and a secondary layer and with a secondary chamber in the mid layer for fluid flow therethrough. The primary layer is positioned between the primary chamber and the mid layer, and the secondary layer is positioned between the mid layer and the exterior. The hose includes an inlet opening for fluid flow from the primary chamber to the secondary chamber and an outlet opening for fluid, flow from the secondary chamber to the exterior. The invention also includes methods of making such a hose.
A feature of the invention is the provision of the restriction device as a secondary chamber which can be cut in the material in a precision manner. A further feature is the method of manufacture utilizing a continuous strip or, in one embodiment, two continuous strips, including the steps of cutting, glueing, folding and pressing, all in a continuous high speed operation.
The multiple layer section and the secondary chamber may have various configurations, including those specific embodiments hereinafter disclosed.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a length of multiple chamber hose, partly broken away, and showing the presently preferred embodiment of the invention;
FIGS. 2 and 3 are enlarged sectional views taken along the lines 2--2 and 3--3 of FIG. 1, respectively;
FIG. 4 is a plan view of a strip of the material used for forming the hose of FIG. 1, and illustrating the openings formed in the strip of material prior to folding;
FIG. 5 is an enlarged partial view similar to that of FIG. 4 showing an alternate configuration for the secondary chamber;
FIG. 6 is a top view of a portion of a length of hose showing another alternative embodiment with flaps;
FIG. 7 is a partial sectional view taken along the line 7--7 of FIG. 6;
FIG. 8 is a view similar to that of FIG. 5 showing another alternative embodiment of the invention;
FIG. 9 is another view similar to that of FIGS. 5 and 8 showing another alternative embodiment;
FIGS. 9A and 9B are partial sectional views of a hose produced with the strip of FIG. 9 and illustrating the operation of the secondary chambers;
FIG. 10 is a view similar to that of FIG. 4 showing another embodiment of the cutting of a strip of material prior to folding in;
FIG. 11 is a cross sectional view of the hose formed from the strip of FIG. 10;
FIG. 12 is a sectional view taken along the line 12--12 of FIG. 11;
FIG. 13 is a view similar to that of FIG. 4 showing another alternative embodiment of the invention;
FIG. 14 is a cross sectional view of a hose produced from the strip of FIG. 13;
FIG. 15 is a cross sectional view similar to that of FIG. 2 showing an alternative embodiment with a second strip forming the mid layer;
FIG. 16 is a top view of the second strip of FIG. 15;
FIG. 17 is a view similar to that of FIG. 4 showing another alternative embodiment of the invention;
FIG. 18 is a cross sectional view of a hose formed from the strip of FIG. 17;
FIG. 19 is an end view of a hose forming strip showing an extruded configuration;
FIG. 20 is a top view of a length of multiple chamber hose, partly broken away, showing another alternative embodiment of the invention;
FIG. 21 is a perspective view of the hose of FIG. 20, illustrating the manufacture of the hose;
FIG. 22 is a sectional view taken along the line 22--22 of FIG. 20;
FIG. 23 is a partial sectional view taken along the line 23--23 of FIG. 20;
FIGS. 24, 25 and 26 are views corresponding to FIGS. 21,22 and 23, respectively, of another alternative embodiment; and
FIGS. 27, 28 and 29 are another set of views corresponding to FIGS. 21, 22 and 23, respectively, of another alternative embodiment.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The presently preferred embodiment of a hose 31 is shown in FIGS. 1-4. The hose is made from a single strip 32 of a waterproof material, typically a plastic such as polyethylene. The hose has a primary chamber 33 and a plurality of secondary chambers 34. The hose includes a multiple layer section comprising a primary layer 35, a mid layer 36 in an edge portion 36a, and a secondary layer 37 in an edge portion 37a. Each of the secondary chambers 34 has a chamber inlet 38 and a chamber outlet 39. Inlet openings 40 are provided in the primary layer 35 and outlet openings 41 are provided in the secondary layer 37. The strip 32 has opposing edges 42, 43.
Long lengths of the hose may be formed from the strip 32 in a continuous operation. The secondary chambers 34 and the openings 40, 41 are die cut or otherwise formed in the strip. Alternative methods of cutting include laser cutting and heat cutting. Next an adhesive is applied to the underside of the strip at the primary layer 35, typically in the zone 48 defined by the dashed lines, and the edge 42 with the mid layer 36 is folded under and bonded to the primary layer 35 by the adhesive. This adhesive layer is shown by the heavy line 49 in FIG. 2. Another layer of adhesive is applied on the secondary layer 37, typically in the zone 50 defined by the edge 43 and the dashed line. The strip is folded to bring the secondary layer 37 into engagement with the mid layer 36, as shown in FIG. 2. This adhesive layer is shown by the heavy line 51 in FIG. 2. If desired, a bead of adhesive 52 may be applied between the primary layer and the secondary layer, and a bead of adhesive 53 may be applied between the mid layer and the secondary layer for additional strength. Also, heat sealing may be utilized in place of adhesive bonding if desired. Vibration or sonic bonding also is a method of bonding plastic material.
Typically during the folding and bonding operations, the hose passes between rollers which produce a substantially flat structure, with the fold lines indicated by the phantom lines 54, 54a and 55 in FIG. 4. However when the primary chamber 33 is filled with water under moderate pressure, the hose assumes a shape substantially as shown in FIGS. 1 and 2, with the actual shape depending upon the water pressure. With higher pressure, the hose is more nearly circular.
In operation, a water supply is connected to the primary chamber 33 at one end of a length of a hose, with the other end of the hose clamped shut. Water flows from the primary chamber through the inlet openings 40 into the chamber inlets of the secondary chambers. The secondary chambers typically are serpentine, and provide restricted flow between the chamber inlet and the chamber outlet, and water flows from the secondary chamber through the outlet openings to the exterior of the hose at a relatively slow rate. The rate of flow is determined by the dimensions of the hose, including the size and shape of the secondary chambers, and by the pressure in the primary chamber. The secondary chambers may take various shapes, and several forms are disclosed. In the embodiment of FIGS. 1-4, the secondary chambers have a square wave configuration.
With the construction of the present invention, the secondary chambers may be precisely cut so that they provide uniform flow from each of the outlet openings, while operating at high production rate. Also, the secondary chamber may be configured to provide compensation for variations in supply pressure and maintain a substantially uniform output flow rate.
An alternative shape for the secondary chamber is shown in FIG. 5 with a saw tooth pattern 34a.
Another alternative construction is shown in FIGS. 6 and 7, with a flap 56 in the primary layer 35 to provide the inlet opening 40 and with a flap 57 in the secondary layer 37 to provide the outlet opening 41. Typically the openings at 40, 41 will be produced by punching, while the flaps 56, 57 will be produced by lancing. In the preferred embodiment, the flaps 56 will be bonded to the primary layer 35 by an adhesive at 58, while the flaps 57 will be free. Use of the flap 57 at the outlet opening provides protection for the secondary chamber when the hose is not pressurized. The use of flaps eliminates the requirement of removing the material punched out for the openings 40, 41.
Another shape for the secondary chamber is shown in FIG. 8, with the chamber 34b formed of alternating offset sections 60, 61, with the offset sections joined by circular sections 62. With this configuration, additional turbulent flow is obtained in the circular sections, thereby obtaining increased flow restriction in a lesser distance. This embodiment is especially suited for input pressure compensation.
Another alternative form for the secondary chamber is shown as 65 in FIGS. 9, 9A and 9B. In this embodiment, the inlet chamber 38 extends to the fold line 54 and the outlet chamber 39 extends to the edge 42 of the strip. Then when the strip is folded to form the hose, the open edge of the chamber 38 serves as the inlet opening or openings 40a and the open edge of the chamber 39 serves as the outlet opening or openings 41a. The sectional FIGS. 9A and 9B are of a finished hose while FIG. 9 is of the film prior to folding. The section lines on FIG. 9 are used to show where the sections are taken of the finished hose.
Another alternative embodiment is shown in FIGS. 10-12 with the secondary chamber 66 being formed by cut outs 66a at edge 42 and cut outs 66b at edge 43. The edge 42 is folded back on itself at line 54 and cemented in place, and the edge 43 is folded back on itself at line 55a and cemented in place, as shown in FIG. 11. Preferably, a registration notch 67 is formed in one edge and a registration flap 68 is formed in the other edge, with the flap being positioned in the notch on folding, as shown in FIG. 12 for maintaining alignment of the cut outs 66a, 66b to form the secondary chamber 66. This embodiment can be used in reducing waste when several hoses are being produced in parallel from a single wide film strip. A cut out at each end of the chamber 66 at 38 and 39 could extend to the respective fold lines 54 and 55a to serve as the inlet and outlet openings, in place of the openings 40 and 41.
In the embodiment illustrated in FIGS. 13, 14, the secondary chamber 34 is formed in the middle of the strip 32, with the strip folded over on opposite sides of the secondary chamber at lines 71, 72 to form the multiple layer section, and with the edges 42, 43 joined together away from the multiple layer section.
In the embodiment of FIGS. 15 and 16, the mid layer of the multiple layer section is formed of a separate strip 75, with the secondary chambers formed in this separate strip. A short length of the separate strip may be used for each secondary chamber, or a continuous separate strip may be utilized with the secondary chambers formed therealong in the same manner as with the strip 32. A locating button 76 maybe formed in the secondary strip 75 if desired. In assembly, the strip 75 is adhered to one edge of the strip 32 and the other edge of the strip 32 is adhered to the strip 75, with the strip 75 serving as the mid layer 36 as shown in FIG. 15.
Another embodiment is shown in FIGS. 17 and 18, with the secondary chamber formed by a plurality of openings 79 along the edge 42 and another plurality of openings 80 along the edge 43, with the ends of opposed openings aligned to provide a continuous secondary chamber when assembled in the configuration of FIG. 18. The edge 42 is folded back on itself along the line 81 and the edge 43 is folded back on itself along the line 82, and the folded over edges are joined together to form the primary chamber and the multiple layer section. In this embodiment, the mid layer of the multiple layer section comprises two layers 36a, 36b, and the secondary chamber alternates between the two sections. In an alternative configuration, the openings 79 could be joined to form a continuous opening and the openings 80 could be joined to form a continuous opening, with a resultant secondary chamber 34 having a double height produced by the double thickness of the strip material comprising the mid layer.
The strip 32 is usually formed with a cross-section of substantially uniform thickness, as is obtained with the conventional blown film or bubble plastic strip manufacturing process. Alternatively, the strip can be produced by extrusion, and in this instance, the thickness of the strip can be varied if it is desired to have one portion of the hose thicker or thinner than another. One such arrangement is shown in FIG. 19 which is an end view of a strip 32a produced by extrusion. This strip is made thicker along the edge 42 which provides the mid layer 36 and can be used when a higher flow rate secondary chamber is desired. Alternatively, the mid layer 36 can be made thinner than the remainder of the strip when a lower flow rate secondary chamber is desired.
Another alternative embodiment is shown in FIGS. 20-23, wherein the mid layer 36 between the primary layer 35 and secondary layer 37 is formed as a flap 85 cut out of the strip of material and folded inwardly. Elements corresponding to those of prior embodiments are identified by the same reference numbers. In manufacture, a thin adhesive film 86 and adhesive beads 87 are applied along the edge of the strip which forms the primary layer 35, typically in the pattern illustrated in FIG. 21. The adhesive film 86 is very thin and serves to hold the flap 85 in place. The adhesive beads are used to form the inlet openings 40. The strip of material utilized for forming the hose typically is in the order of 0.004 to 0.015 inches thick. The adhesive beads should be a bit thicker, and typically with a minimum thickness of 0.007 inches, so that the space formed by the beads between the primary and secondary layers can function as the inlet opening. As with the earlier embodiments, the secondary chamber 34 and the flap 85 may have various configurations, depending on the amount of flow control desired. Also, a flap 57, as shown in FIG. 7, may be used for the outlet opening 41.
The embodiment of FIGS. 24-26 is similar to that of FIGS. 20-23, with the flap 85 folded to the outside to serve as the secondary layer 37, and with the secondary chamber 34, chamber inlet 38 and chamber outlet 39 formed adjacent to the edge of the strip, which serves as the midlayer 36.
The embodiment of FIGS. 27-29 is similar to those of FIGS. 20-23 and FIGS. 24-26. In this embodiment, the flap 85 is formed from the opposite edge of the strip, with the flap folded between the edges to serve as the mid-layer 36, with the secondary chamber 34 formed in the flap. The operation of the last three embodiments is the same as that of the earlier embodiments. Water flows through the primary chamber 35 into the inlet opening 40 formed by the adhesive beads, and then into the chamber inlet 38 of the secondary chamber 34. The water flows along the secondary chamber 34 to the chamber outlet 39, and then outward to the area to be irrigated through the outlet opening 41. | A multiple chamber hose for drip irrigation and the like, with a primary chamber for fluid flow therethrough and a multiple layer section having a primary layer, a mid layer and a secondary layer, and with a secondary chamber in said mid layer for fluid flow therethrough. The primary layer is positioned between the primary chamber and the mid layer, and the secondary layer is positioned between the mid layer and the exterior. The hose includes an inlet opening for fluid flow from the primary chamber to the secondary chamber and an outlet opening for fluid flow from the secondary chamber to the exterior. The invention also includes methods of making such a hose. | 8 |
RELATED APPLICATIONS
[0001] This application claims priority under 35 U.S.C. §119 based on U.S. Provisional Application No. 62/055,751, filed on Sep. 26, 2014. The disclosure of U.S. Provisional Application No. 62/055,751 is incorporated herein by reference.
FIELD OF INVENTION
[0002] The present disclosure contemplates an apparatus, system and method for conducting strength training exercises using resistance bands. The present disclosure further contemplates an apparatus, system, and method for conducting strength training exercises where resistance bands may be attached to a portable platform base.
BACKGROUND
[0003] Previous apparatuses and systems used for resistance workouts are complicated and unwieldy. Previous apparatuses and systems are also susceptible to limiting constraints, such as the portability of the device, the limited use of a single participant, and the lack of personalization to individual skill level. Still further, previous anchoring apparatuses and systems lack versatility in their integration into an exercise program. For example, some platforms are designed to only incorporate a user's body weight, thereby eliminating its potential use for a heavy lifter, while other platforms have bulky parts or bands that can only be incorporate in a limited number of directions and amount in resistance, thereby eliminating its use for effectiveness.
SUMMARY OF INVENTION
[0004] The present disclosure contemplates portable strength-training apparatus and system for conducting strength-training exercises using resistance bands. The apparatus of the present disclosure can serve as an anchor while conducting strength training exercises using resistance bands. The apparatus and system of the present disclosure can allow for safe strength-training exercises at varying resistance levels while allowing exercises at any angle. Resistance band strength-training may reduce the risk of injury compared to traditional weight-based strength-training The apparatus and system of the present disclosure may allow a user to strength train with resistance bands throughout entire body. The apparatus and system of the present disclosure can be used in home workouts, at the gym, with personal trainers, for professional athletes, for physical therapy, or in the outdoors.
[0005] The apparatus and system of the present disclosure may allow for more rapid alteration of the level of resistance than prior resistance workout apparatuses or systems. The apparatus and system of the present disclosure may allow resistance to be quickly altered by manipulating the length of a resistance band that is already in use or by adding or removing resistance bands. The apparatus and system of the present disclosure allow the user to use multiple resistance bands during a workout. The platform base of the present disclosure is designed to allow multiple bands to be securely attached to the platform base. The variability of the apparatus and system of the present disclosure—manipulating the length of the resistance bands or using multiple bands—may allow the user to experience a wide range of resistance from just a few pounds of resistance up to hundreds of pounds of resistance.
[0006] In one embodiment the portable strength training apparatus can have a platform base with one or more base attachment mechanisms for attaching resistance bands. The platform base can be portable to allow workouts to be conducted at many locations, such as inside a home, outside in a park, in the office, or at the gym. The platform base can be lightweight so that it can be moved by one person. Base attachment mechanisms on the platform base can allow one or more resistance bands to be attached to the platform base. The one or more resistance band(s) can attach to the base attachment mechanisms on the platform base using a hook or clip or other common coupling mechanism. The resistance bands can also wrap around the base attachment mechanisms or weave through the base attachment mechanisms to shorten the effective length of the resistance band allowing the user to quickly alter the difficulty of the strength training exercise. The base attachment mechanisms on the platform base can extend upward from the top surface of the platform base and be located at various positions throughout the top surface of the platform base or the base attachment mechanisms can be situate in base voids that pass through the platform base. When the base attachment mechanisms extend upward from the top surface of the base platform, one or more securing mechanism can be used to secure resistance bands that are wrapped around or weaved through the base attachment mechanism. The securing mechanism can be elastic bands that squeeze the resistance band and part of the base attachment mechanism together thus ensuring that the resistance band does not unwind or unweave from the base platform during use.
[0007] A person using the platform base can stand on the top surface of the platform base when conducting strength-training exercises or the person can stand off of the platform base if the platform base is fixed to an immobile structural component or secured with weights. Standing on the platform base can allow the user to incorporate resistance bands in multiple strength exercises. The portable strength-training apparatus can have a hinge in the platform base that allows the platform base to fold over on to itself for easier portability. The portable strength-training apparatus can have a handle such as a handle which may allow the user to more easily transport the portable strength-training apparatus.
[0008] The present disclosure further contemplates a portable strength training system that includes a platform base, resistance bands, base attachment mechanisms, human attachment mechanisms, and coupling mechanisms. The resistance bands may have the coupling mechanisms attached to either end with one end coupling with the base attachment mechanisms and one end coupling to the human attachment mechanism. The human attachment mechanism can be hand grips, wrist straps, ankle straps, a waist strap, or a workout bar. The human attachment mechanisms can allow one or more resistance bands to be attached. The workout bar can also be broken down in to two or more components for transporting with the base platform. Again, the portable strength training system of the present disclosure may allow for safe strength training exercises at varying resistance levels while allowing exercises at any angle. The system of the present disclosure may allow the user to incorporate nearly unlimited levels of resistance to multiple strength-training exercises.
[0009] The present disclosure further contemplates a method for strength training that includes the steps of coupling one or more resistance bands to a portable platform base, where the platform base has a top surface, a bottom surface, and a plurality of base attachment mechanisms. In the contemplated method the one or more resistance bands are coupled to the platform base at the base attachment mechanisms via a coupling mechanism. The method of strength training further includes standing on top of the platform base and stretching the one or more resistance bands by applying pressure to one or more of a human interface mechanism. The one or more of the human interface mechanisms may be coupled to the one or more resistance bands which are in turn coupled to the platform base at the base attachment mechanisms.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] The foregoing and other features of the present disclosure will become more fully apparent from the following description, taken in conjunction with the accompanying drawings. Understanding that these drawings depict only several embodiments in accordance with the disclosure and are, therefore, not to be considered limiting of its scope, the disclosure will be described with additional specificity and detail through use of the accompanying drawings.
[0011] FIG. 1 is a top view of an example portable strength training apparatus with base attachment mechanisms situated in base voids.
[0012] FIG. 2 is a top view of an example portable strength training apparatus with base attachment mechanisms situated in base voids where the platform base is folded along the hinge.
[0013] FIG. 3 is a side view of a portion of an example portable strength training system with base attachment mechanisms extending upward from the top surface of the platform base.
[0014] FIG. 4 is a perspective view of an example portable strength training system with base attachment mechanisms extending upward from the top surface of the platform base.
[0015] FIG. 5 is a perspective view of an example portable strength training system with base attachment mechanisms extending upward from the top surface of the platform base.
[0016] FIG. 6 is a flowchart of an example method for strength training.
DETAILED DESCRIPTION
[0017] In the following detailed description, reference is made to the accompanying drawings, which form a part hereof. In the drawings, similar symbols typically identify similar components, unless context dictates otherwise. The illustrative embodiments described herein are not meant to be limiting. Other embodiments may be utilized, and other changes may be made, without departing from the spirit or scope of the subject matter presented here. It will be readily understood that the aspects of the present disclosure, as generally described herein, and illustrated in the Figures, may be arranged, substituted, combined, and designed in a wide variety of different configurations, all of which are explicitly contemplated and make part of this disclosure.
[0018] FIG. 1 and FIG. 2 depict an example portable strength training apparatus 100 having a platform base 101 having a top surface 1011 , a bottom surface 1012 , and a plurality of base attachment mechanisms 103 , wherein one or more of the plurality of base attachment mechanisms 103 may be removably coupled with a resistance band. In FIG. 1 the base attachment mechanisms 103 are situated within base voids 103 that pass through the platform base 101 . The base attachment mechanisms 103 may be metal, plastic, or another material capable of withstanding the pressure of the resistance bands. The base voids 102 may be placed anywhere throughout the platform base 101 and there may be any number of base voids 102 and corresponding base attachment mechanism 103 . The base voids 102 should be large enough to allow coupling between the resistance band and the base attachment mechanism 103 . The platform base 101 may be made of plastic, metal, or another material that will not bow or shift when pressure is applied through the resistance bands. The platform base 101 and included base voids 102 and base attachment mechanisms 103 may be formed using common injection molding, stamping, vacuum molding, or welding processes. The platform base 101 may have a lower weight to allow a single person to transport the portable strength training apparatus 100 .
[0019] Resistance bands 106 (not shown) may be wrapped around one or more of the plurality of base attachment mechanisms 103 before or after the resistance band 106 is coupled to one of the plurality of base attachment mechanism 103 . The wrapping and weaving of the resistance band 106 shortens the effective length of the resistance band 106 , thus increasing the pressure that must be applied to stretch the resistance band 106 . The base voids 102 may allow the resistance bands 106 to wrap around and weave through base attachment mechanisms 103 .
[0020] The portable strength training apparatus 100 may have a hinge 104 . The hinge 104 , as depicted in FIG. 2 , may allow the platform base 101 to fold over on to itself for easier transportation. The portable strength training apparatus 100 may have a handle 105 , such as hand holds, again for easier transportation. The handle 105 may be rope, plastic, metal, or other material capable of sustaining the weight of the portable strength training apparatus 100 during transportation. The handle 105 may be attached to the platform base during molding process, through welding, using an adhesive, or using another method capable of sustaining the weight of the portable strength training apparatus 100 during transportation.
[0021] FIG. 3 depicts a portion of an example portable strength training system 200 with the plurality of base attachment mechanisms 103 extending upward from the top surface 1011 of the platform base 101 when the bottom surface 1012 of the platform base 101 is in contact with the ground. The coupling mechanism 107 allows a resistance band 106 to be removably coupled to one or more of the plurality of base attachment mechanisms 103 . The resistance band 106 may be wrapped around one or more of the plurality of base attachment mechanisms 103 before or after the resistance band 106 is coupled to one of the plurality of base attachment mechanism 103 . One or more securing mechanisms 1031 can be used to secure resistance bands 106 that are wrapped around or weaved through the base attachment mechanism 103 . The securing mechanism 1031 can be elastic band that squeezes the resistance band 106 and part of the base attachment mechanism 103 together to further lock the resistance band 106 during use so the resistance band 106 does not unwind or unweave from the base platform 101 during use.
[0022] FIG. 4 and FIG. 5 depict example portable strength training systems 200 with the plurality of base attachment mechanisms 103 extending upward from the top surface 1011 of the platform base 101 when the bottom surface 1012 of the platform base 101 is in contact with the ground. Again the coupling mechanism 107 allows a resistance band 106 to be removably coupled to one or more of the plurality of base attachment mechanisms 103 . Again, resistance bands 106 may be wrapped around one or more of the plurality of base attachment mechanisms 103 before or after the resistance band 106 is coupled to one of the plurality of base attachment mechanism 103 . The wrapping and weaving of the resistance band 106 shortens the effective length of the resistance band 106 , thus increasing the pressure that must be applied to stretch the resistance band 106 .
[0023] The portable strength training systems 200 includes one or more human interface mechanisms 109 . The human interface mechanism 109 allow the one or more resistance bands 106 to be stretched by applying pressure to the one or more human interface mechanisms 109 . The human interface mechanism can be a hand grip or an ankle strap as shown in FIG. 4 or a workout bar as shown in FIG. 5 , or another strap or grip, such as a wrist strap, a waist strap, or foot grip. Any combination of human interface mechanisms 109 can be applied to vary the maneuver and the angle of the maneuver used to stretch the resistance bands 106 in order to strengthen difference muscles and muscle groups. Coupling the resistance bands 106 to base attachment mechanisms 103 at different locations on the base platform 101 can also vary the maneuver and the angle of the maneuver used to stretch the resistance bands 106 in order to strengthen difference muscles and muscle groups. When the human interface mechanism is a workout bar as shown in FIG. 5 , it may be disassembled into two or more pieces for easier transport, thus further enhancing the portability of portable strength training systems 200 of the present disclosure. The human interface mechanisms 106 can have a rounded or V-shaped area that allows coupling with multiple resistance bands 106 via the coupling mechanisms 107 . The coupling mechanisms 107 may be metal or plastic clips or hooks or another element capable of removably coupling the resistance band 106 to the base attachment mechanisms 103 and the human interface mechanisms 109 .
[0024] The resistance bands 106 may be of varying length, diameter, and elastic material to allow for varying resistance. The resistance bands 106 may include a protective cover made of cloth or another enclosing material that protects the user of the portable strength training system 200 in case the resistance band 106 breaks during use. As shown in FIG. 5 , multiple resistance bands 106 can be used between the same base attachment mechanisms 103 and human interface mechanism 109 to increase the pressure needed to stretch the resistance bands 106 . The user of the portable strength training system 200 of the present disclosure can apply downward pressure to the base platform 101 with a hand as shown in FIG. 4 or by standing on the base platform 101 as shown in FIG. 5 . The base platform 101 can also be rendered immobile by fixing it to secure structure, applying weights to the base platform 101 , by the user applying pressure to the base platform 101 through a body part, or by a spotter applying pressure to the base platform 101 by standing on it or applying pressure through a body part.
[0025] FIG. 6 depicts an example of a method for strength training 300 that includes coupling one or more resistance bands to a platform base 301 , standing on the top surface of the platform base 302 , and stretching one or more resistance bands by applying pressure to one or more human interface mechanisms 303 . The method for strength training 300 may use the portable strength training apparatus 100 and portable strength training system 200 described above.
[0026] While various aspects and embodiments have been disclosed herein, other aspects and embodiments will be apparent to those skilled in the art. The various aspects and embodiments disclosed herein are for purposes of illustration and are not intended to be limiting.
[0027] The sections above may set forth one or more but not all exemplary embodiments and thus are not intended to limit the scope of the present disclosure and the appended claims in any way. Embodiments have been described above with the aid of functional building blocks illustrating the implementation of specified functions and relationships thereof. The boundaries of these functional building blocks have been arbitrarily defined herein for the convenience of the description. Alternate boundaries can be defined so long as the specified functions and relationships thereof are appropriately performed.
[0028] The foregoing description of specific embodiments will so fully reveal the general nature of the disclosure that others can, by applying knowledge within the skill of the art, readily modify and/or adapt for various applications such specific embodiments, without undue experimentation, without departing from the general concept of the present disclosure. Therefore, such adaptation and modifications are intended to be within the meaning and range of equivalents of the disclosed embodiments, based on the teaching and guidance presented herein. It is to be understood that the phraseology or terminology herein is for the purpose of description and not of limitation, such that the terminology or phraseology of the present specification is to be interpreted by the skilled artisan in light of the teachings and guidance.
[0029] Following from the above description summaries, it should be apparent to those of ordinary skill in the art that, while the methods, apparatuses and data structures herein described constitute exemplary embodiments of the current disclosure, it is to be understood that the inventions contained herein are not limited to the above precise embodiments and that changes may be made without departing from the scope of the invention as claimed. Likewise it is to be understood that it is not necessary to meet any or all of the identified advantages or objects of the invention disclosed herein in order to fall within the scope of the inventions, since inherent and/or unforeseen advantages of the current disclosed embodiments may exist even though they may not have been explicitly discussed herein. | The present disclosure contemplates portable strength-training apparatus, system, and method for conducting strength-training exercises using resistance bands. The apparatus of the present disclosure can serve as an anchor while conducting strength training exercises using resistance bands. The apparatus and system of the present disclosure can allow for safe strength-training exercises at varying resistance levels while allowing exercises at any angle. The apparatus, system, and method of the present disclosure may allow a user to strength train with resistance bands throughout entire body. The apparatus and system of the present disclosure may include a base platform with base attachment mechanisms that can be coupled with resistance bands which are in turn coupled with human interface mechanisms such as grips, wraps, or bars. | 0 |
This is a divisional application of Ser. No. 07/780,301, filed Oct. 22, 1991, now U.S. Pat. No. 5,183,603.
BACKGROUND OF THE INVENTION
This invention relates to a carbon fiber and, more particularly, to a process for producing a pitch carbon fiber bundle adjusted in the form of a coil.
In general, carbon fibers are roughly divided into a PAN system and a pitch system. PAN carbon fibers are produced by firing polyacrylonitrile fiber under specific conditions. Pitch carbon fibers are produced by melt spinning an anisotropic pitch or isotropic pitch and thereafter infusibilizing and carbonizing it.
These carbon fibers are applied to products adapted for features depending upon raw materials and characteristics and widely utilized as materials for aerospace industry, sports or leisure products.
The carbon fibers which have heretofore been produced have excellent physical and chemical properties such as light weight, high strength, heat resistance and chemical resistance. However, the carbon fibers generally exhibit a behavior as brittle materials and how low elongation and inferior softness. Accordingly, the prior art carbon fibers are not necessarily suitable as materials for which these characteristics are required. Further, in the prior art process for producing carbon fibers, it is difficult to produce fibers or fiber bundles having excellent elongation and elasticity.
In view of such prior art, we have already proposed a process for producing a curl-shaped fiber comprising an isotropic texture and an anisotropic texture and having excellent elasticity by separately feeding an isotropic pitch and an anisotropic pitch and spinning these pitches from a spinneret at the same time (Japanese Patent Laid-Open Publication No. 90626/1991).
According to this process, carbon fiber materials having excellent elasticity can be obtained with relatively low cost. However, the softening point of the isotropic pitch is different from that of the anisotropic pitch and their attenuation behaviors after discharge are different. Accordingly, it is not necessarily easy to spin the isotropic and anisotropic pitches at the same time. Further, in the case where the isotropic and anisotropic textures only coexist or coexisted these fibers are merely infusibilized and carbonized, the resulting fibers are randomly curled every single yarn and therefore bulky and wavy fibers are obtained, but fibers having good stretchability cannot be obtained. Thus the fibers are not entirely satisfactory.
SUMMARY OF THE INVENTION
An object of the present invention is to provide an effective process for obtaining a carbon fiber bundle comprising a regular fiber bundle and having excellent stretchability and elasticity.
We have studies in order to obtain a carbon fiber having excellent stretchability. We have now found that a coil-shaped fiber bundle having the same coil direction and having excellent stretchability can be obtained by compositing at least two pitches having specific nature to spin them as single fibers, bundling these single fibers, infusibilizing the thus obtained bundle under specific conditions and carbonizing it.
The process for producing the coil-shaped carbon fiber bundle according to the present invention is achieved on the basis of the finding described above. More particularly, the process for producing the coil-shaped carbon fiber bundle according to the present invention comprises the steps of: compositing at least two pitches wherein the maximum difference in coefficient of linear contraction in the direction of a fiber axis during carbonization of spun pitches is at least 5% and the difference in the softening points of the pitches to be composited is within 10° C. to spin the pitch composite as single fibers; bundling the thus spun single fibers to form a fiber bundle; then infusibilizing the resulting fiber bundle under tension; and carbonizing the fiber bundle.
Another embodiment of the present invention comprises the steps of: compositing at least two pitches wherein the maximum difference in coefficient of linear contraction in the direction of a fiber axis during carbonization of spun pitches is from 1% to 5% and the difference in the softening points of the pitches to be composited is within 10° C. to spin the pitch composite as single fibers; bundling the thus spun single fibers to form a fiber bundle; then twisting the fiber bundle and/or infusibilizing the resulting fiber bundle under tension with twisting; and carbonizing the fiber bundle.
The thus obtained carbonized fibers comprise coil-shaped fiber bundle having excellent stretchability wherein the coil direction of individual single fibers is the same and highly regulated as shown in FIG. 1.
BRIEF DESCRIPTION OF THE DRAWING
In the drawing:
FIG. 1 is a microphotograph showing the shape of a coil-shaped carbon fiber bundle obtained by a process described in Example of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
The source and composition of pitches which are spinning raw materials in the present invention are not limited and known petroleum and coal spinning pitches can be widely used provided that the maximum difference in coefficient of linear contraction in the direction of a fiber axis during carbonization is at least 5% and the difference in the softening points of the pitches is within 10° C.
Further, in the second embodiment of the present process, pitches wherein the maximum difference in coefficient of linear contraction in the direction of a fiber axis during carbonization is from 1% to 5% can also be used. In this case, additional operation of twisting is necessary to obtain a highly regulated coil-shaped fiber bundle as in the first embodiment of the present invention.
The pitches can be selected from optically isotropic pitches, optically anisotropic pitches, isotropic component-anisotropic component-mixed pitches, or combinations thereof.
The process for compositing the spinning pitches of plural types to spin as single fibers can be a process wherein the pitches are composited by feeding at least two pitches into a spinning apparatus in unmixed state, and melt spinning the pitches at the same time by means of a composite nozzle. A spinning apparatus described in Japanese Patent Laid-Open Publication No. 90626/1991 can be used as the apparatus for spinning such composited single fibers.
The torsion or twist of the fibers in the present invention is developed by the difference in linear contraction coefficient during carbonization of pitches from which composited fibers are produced. If the difference in percent shrinkage is less than 5%, fibers will slightly waved and highly regulated coil-shaped fiber bundles cannot be obtained without twisting.
In composite spinning at least two pitches, it is preferred that the optimum spinning temperatures of respective pitches are consistent. Usually, the viscosities of the spinning pitches largely vary depending upon temperature and therefore the optimum spinning temperature range is narrow. Therefore, in order to spin well, it is preferred that viscosities of the pitches at spinning temperatures be substantially approximate. For this purpose, it is vital that the difference in the softening points of the pitches is not more than 10° C.
The proportion of cross-section of the fiber of the pitch based on total cross-section in compositing pitches of plural types influences the coiling characteristics of the obtained carbon fibers. The larger amount of the pitch having a large coefficient of linear contraction during carbonization has the larger extent of torsion. Thus, good coil-shaped fiber bundle can be obtained. While the proportion of the pitch having a large coefficient of linear contraction is not limited in the present invention, it is preferably within the range of about 5% to about 95%, more preferably from 20 to 90%, and most preferably from 30 to 80%. If the amount of the pitch having a large linear contraction coefficient during carbonization is less than about 5%, the extent of coilability will be reduced and its stretchability tends to be reduced. If the amount of the pitch having a large linear contraction coefficient during carbonization is more than 95%, poor coil-shaped product will be obtained.
When the composite pitch fibers are stranded, the direction of the coil formation becomes uneven if the position of each pitch in the fibers is not the same. In such a case, it is preferred that the spun pitches be treated with a bundling agent to fix the direction to lateral direction of fibers. The bundling agents used for such a purpose include ethyl alcohol, a mixture of ethyl alcohol with water, and a mixture of ethyl alcohol with a silicone oil-aqueous emulsion.
It is preferred that the filament number of the fiber bundle be not more than 10,000.
The pitch fibers tend to slightly shrink in the infusibilization step and therefore the bundled fiber is disturbed. When the thus disturbed bundle is carbonized, the direction of torsion is disturbed and a good coil-shaped product cannot be obtained. We have now found that a coil-shaped fiber bundle having the same coil direction and having excellent stretchability can be obtained by infusibilizing the bundle of the fibers obtained under conditions as described above under tension and carbonizing it. While the infusibilization step can be suitably adjusted depending upon types of the spinning pitches used and combinations thereof, the infusibilization is preferably carried out under a tension of at least 0.0001 gram per each filament, and more preferably at least about 0.0004 grams per each filament.
While the carbonization step is desirably carried out substantially under a non-tension, the tension force of no more than 0.05 grams per each filament may be present. If the tension of more than 0.05 grams per each filament is applied during carbonization, the difference in the percent linear shrinkage of composited pitches will be reduced and a good coil-shaped product cannot be obtained.
While the temperature used in infusibilization of carbon fiber bundle is not limited, infusibilization can be usually carried out at a temperature within the range of 220° C. to 300° C. Carbonization can be carried out at a temperature within the range of 700° to 3,000° C.
In the second embodiment of the present invention, by giving twist to the bundled fiber before infusibilization and/or during infusibilization, a good coil-shaped fiber bundle having good stretch characteristics can be obtained. In this case, the number of twist is preferably at least 10 turn/m.
The thus produced pitch carbon fiber bundle has such a coiled morphology that single fibers are arranged neatly side by side in the form of a coil as shown in FIG. 1. When load is applied, the fiber bundle exhibits an elongation of 10% to 100% or more. When load is released, the fiber bundle is instantly restored to original length. Thus, the fiber bundle exhibits a behavior similar to an elastic rubber cord. Further, this stretch characteristics is maintained after stretching is repeated 10,000 times as shown in the following Examples.
Furthermore, the coil-shaped carbon fiber bundle having desired stretch characteristics can be produced by adjusting the composite proportion of the spinning pitches, the size of the diameter of fibers, the number of fiber bundle and the like as shown in the following Examples.
Petroleum heavy oils were used as raw materials to prepare spinning pitches A to F having different linear contraction coefficient during carbonization as shown in Table 1.
EXAMPLE 1
A spinning pitch B and a spinning pitch A shown in Table 1 were separately fed to the inside (pitch B) and outside (pitch A) of a sheath-core type composite nozzle having a diameter of an inside nozzle of 0.2 mm and a diameter of an outside nozzle of 0.5 mm, respectively, and spun at the same time from a discharge hole to obtain a composite pitch fiber comprising pitches A and B. During this time, the discharge pressure of each pitch was adjusted so that the discharge ratio of A:B is 20:80. Spinnability was good and yarn cutting did not occur over one hour. 1,500 composite pitch fibers were bundled using ethyl alcohol, infusibilized under tension of 0.0004 grams per each fiber in air at 290° C., thereafter tension was released and carbonization was carried out in a nitrogen atmosphere at 1,000° C. The thus obtained pitch carbon fiber bundle has such a coiled morphology that single fibers are arranged in the form of coil as shown in the microphotograph of FIG. 1. When load was applied, the fiber bundle exhibited an elongation of at least 100%. When load was released, the fiber bundle was instantly restored to original length. Thus, the fiber bundle exhibited a behavior similar to an elastic rubber cord. Further, this stretchability was maintained after stretching was repeated 10,000 times.
EXAMPLE 2
The fiber bundle spun and infusibilized as in Example 1 was carbonized under a tension of 0.01 gram per each fiber to obtain a coil-shaped fiber bundle. The thus obtained fiber bundle exhibited coil-shaped torsion as in Example 1 and the elongation obtained by applying load was 65%.
COMPARATIVE EXAMPLE 1
The composite pitch fiber bundle spun as in Example 1 was infusibilized under a non-tension and thereafter carbonized. The fiber bundle was disturbed in the infusibilization step and therefore the coil-shaped portion and the coil-free portion were present and its stretchability was inferior.
COMPARATIVE EXAMPLE 2
The fiber bundle spun and infusibilized as in Example 1 was carbonized under a tension of 0.1 gram per each fiber to obtain a coil-shaped fiber bundle. The thus obtained fiber bundle was not in the form of a coil and its stretchability was not observed at all as with conventional carbon fibers.
COMPARATIVE EXAMPLE 3
A spinning pitch D and a spinning pitch A at a ratio of 80:20 were composited and spun as in Example 1, and infusibilization and carbonization were carried out. In this case, the difference in their linear contraction coefficient during carbonization was small and therefore a coil-shaped fiber bundle was not obtained.
COMPARATIVE EXAMPLE 4
A spinning pitch B and a spinning pitch C at a ratio of 80:20 were composited and spun as in Example 1. The difference in the softening points of both pitches was large and therefore the respective spinnable temperature range was different, yarn cutting frequently occurred at any spinning temperature and composite fibers were not obtained.
EXAMPLE 3
A spinning pitch B and a spinning pitch A shown in Table 1 were separately fed to the inside and outside of a sheath-core composite nozzle as in Example 1, respectively, and spun at the same time from a discharge hole to obtain a composite pitch fibers composed of the spun pitches A and B. During this time, the discharge pressure of each pitch was adjusted, thereby various composite pitch fibers having different discharge proportion were obtained. In this case, spinnability was good at any discharge proportion and yarn cutting did not occur over one hour.
The thus obtained 1,500 composite pitch fibers were bundle using ethyl alcohol, infusibilization and carbonization were carried out as in Example 1. As shown in Table 2, in the cases of the thus obtained various coil-shaped carbon fiber bundles having different discharge ratios, it was observed that the stretch characteristic of the fiber bundle was optionally controlled by adjusting the discharge ratio of the spinning pitch B as shown in Table 2 below.
EXAMPLE 4
A coil-shaped carbon fiber bundle was obtained as in Example 3 except that a spinning pitch A and a spinning pitch B shown in Table 1 were separately fed to the inside and outside of a sheath-core composite nozzle as in Example 1, respectively. As shown in Table 2, in the cases of the thus obtained various coil-shaped carbon fiber bundle having different discharge ratios, it was observed that the stretch characteristic of the fiber bundle was optionally controlled by adjusting the discharge ratio of the spinning pitch B.
EXAMPLE 5
A coil-shaped carbon fiber bundle was obtained as in Example 1 except that a spinning pitch A and a spinning pitch B were fed to the inside and outside of the nozzle, respectively, and the fiber diameter of composite pitch fibers or the number of bundled fibers were varied.
As shown in Table 3 below, it was observed that the stretch characteristic of the obtained various coil-shaped carbon fiber bundles was optionally controlled by adjusting the fiber diameter of single fibers or the bundle number of the fibers.
EXAMPLE 6
A spinning pitch F and a spinning pitch E shown in Table 1 were separately fed to the inside (pitch F) and outside (pitch E) of a sheath-core type composite nozzle having a diameter of an inside nozzle of 0.2 mm and a diameter of an outside nozzle of 0.5 mm, respectively, and spun at the same time from a discharge hole to obtain a composite pitch fiber comprising pitches E and F. During this time, the discharge pressure of each pitch was adjusted so that the discharge ratio of E:F is 20:80. Spinnability was good and yarn cutting did not occur over one hour. 1,500 composite pitch fibers were bundled using ethyl alcohol, then the obtained bundle was twisted by 10 turn/m, and in this twisted state, the bundle was infusibilized under tension of 0.0004 grams per each fiber in air at 290° C., thereafter tension was released and carbonization was carried out in a nitrogen atmosphere at 1,000° C. The thus obtained pitch carbon fiber bundle has such a coiled morphology that single fibers are arranged in the form of highly regulated coil bundle. When load was applied, the fiber bundle exhibited an elongation of at least 100%. When load was released, the fiber bundle was instantly restored to original length. Thus, the fiber bundle exhibited a behavior similar to an elastic rubber cord. Further, this stretchability was maintained after stretching was repeated 10,000 times.
EXAMPLE 7
The fiber bundle was obtained in the same manner of EXAMPLE 6 except that the pitch A and pitch D were used. The obtained fiber bundle exhibited good coil shape and good stretchability as in EXAMPLE 6.
COMPARATIVE EXAMPLE 5
The fiber bundle was obtained in the same manner of EXAMPLE 6 except that twisting was not carried out. The obtained fiber bundle had slightly waved shaped and did not become a coil-shaped bundle as in EXAMPLE 6.
TABLE 1______________________________________(Physical Properties of Spinning Pitch) Coefficient Proportion of Linear Soften- of Toluene Quinoline Contraction ing Anisotropic Insoluble Insoluble duringPitch Point Texture Matter Matter CarbonizationName (°C.) (%) (%) (%) (%)______________________________________A 235 99 77 30 5.8B 235 0 56 0 12.9C 260 100 80 33 5.8D 240 52 70 8 8.5E 220 0 59 0 9.8F 220 99 70 23 7.9______________________________________
TABLE 2______________________________________Content of Elongation at a Elongation at aSpinning pitch Load of 100 g Load of 1000 gB in Fiber (%) (%)(%) Ex. 3 Ex. 4 Ex. 3 Ex. 4______________________________________20 30 40 -- --30 -- -- ≧100 ≧10050 45 47 ≧100 ≧10090 65 58 ≧100 ≧100______________________________________
TABLE 3______________________________________Number of Fiber Elongation (%)bundled Diameter Loadfiber (μm) of 20 g Load of 50 g Load of 80 g______________________________________1,000 15 23 38 441,000 25 20 33 413,000 15 9 18 24______________________________________ | The present invention relates to a carbon fiber bundle includes a regular coil-shaped fiber bundle and having excellent stretch characteristic. A process for producing a coil-shaped carbon fiber bundle according to the present invention includes the steps of compositing at least two kind of pitches to spin them as single fibers, bundling the thus spun single fibers to form a fiber bundle, then infusibilizing the resulting fiber bundler under tension and carbonizing the fiber bundle. | 3 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a magnetic film having a high saturated magnetic flux density used in a recording head and a magnetic reproducing head of a hard disk drive (HDD), a magnetic sensor such as a magnetic impedance sensor, and a magnetic circuit component such as a magnetic coil and an inductor; a method for producing the magnetic film; and a thin film head using the magnetic film.
2. Description of the Related Art
In recent years, the maximum recording frequency of HDDs has remarkably increased to about 200 MHz. Furthermore, high-density recording media are likely to have a high coercivity. Therefore, there has been a demand for a recording head material which has a high effective magnetic permeability even at a high frequency and in which a magnetic pole is unlikely to be saturated (i.e., a recording head material which has a high resistivity (high ρ), strong uniaxial anisotropy, and a high saturated magnetic flux density (high Bs)).
In order to satisfy the above-mentioned demand, F—N type material such as FeCrN (J. Appl. Phy. 81(8), Apr. 15, 1997) and FeRhN (IEEE Trans. Magn. VVOl 133. No. 5, 1997) formed by sputtering has been reported as a materiel, for example, with Bs of 2 T (tesla) or more.
The above-mentioned material with high Bs has a low resistivity; therefore, it is difficult to use such material at a high frequency. However, it has been reported that such material is used with a non-magnetic insulator (Al 2 O 3 , SiO 2 , etc.) so as to suppress an eddy current loss (The Japan Society of Applied Magnetics, document of The 103 th Research Institute, p. 2, 1998).
As shown in FIG. 40, U.S. Pat. Nos. 5,543,989 and 5,686,193 disclose a magnetic film with magnetic pole end regions 119 and 123 , including a layered structure of a seed layer of sendust and a bulk layer of sendust.
As material for a single layer with high ρ, Fe—M—O (M=Hf, Zr) (Summary of the lecture in the 122 nd Japan Society of Metal, p. 179 (424) 1998) is known; however, it has a disadvantage of low Bs. It is required that the above-mentioned material with high Bs or high ρ is capable of providing uniaxial anisotropy and suppressing a ferromagnetic resonance loss. For this purpose, heat treatment in a magnetic field or film formation in a magnetic field is conducted.
However, even in the case where uniaxial anisotropy is given to a conventional film with high Bs, a recording magnetic pole used in a thin film head has an increased aspect ratio between the thickness and the width of a magnetic pole due to a decreased width of a track. Therefore, magnetic anisotropy is caused by an anti-magnetic field in a direction perpendicular to the surface of a recording gap between an upper magnetic pole and a lower magnetic pole.
Because of the above, the direction of a magnetization easy axis shifts in the direction perpendicular to the film surface, which complicates a domain structure in the entire magnetic pole. As a result, magnetic characteristics at a high frequency degrade.
Furthermore, in the case where a magnetic pole is formed by a layered structure including a conventional layer with high Bs and an insulation resistant layer, it is required that at least two sources for supplying material are used for forming the layer with high Bs and the insulation resistant layer, and that these layers are alternately formed, which results in a longer period of time of film formation.
Furthermore, in performing a dry etching technique for minute processing (i.e., patterning of a magnetic pole), an etching rate of a magnetic material of transition metal such as Fe, Co, and Ni is substantially different from that of a non-magnetic insulating material such as Al 2 O 3 and SiO 2 . Thus, for example, in the case where radical etching or reactive ion etching (RIE) with a high etching rate is conducted, since these reactions are isotropic, unevenness is formed on cross-sections of the magnetic layer and the non-magnetic insulating layer. Furthermore, when reactive gas to be used for each layer is varied, a processing speed as a whole is decreased due to gas substitution, and a device becomes complicated.
Furthermore, in the case where the above-mentioned film is used in high-frequency recording, a spin valve film is used for a reproducing head. At least one of the magnetic layers included in the spin valve film is a fixed layer whose magnetization is fixed in a direction of medium magnetization, and the direction of fixed magnetization is orthogonal to the direction of uniaxial anisotropy required for a recording magnetic pole film for a high frequency.
The recording magnetic film which has been conventionally developed is produced while uniaxial anisotropy is obtained. Alternatively, after the recording magnetic film is produced, uniaxial anisotropy is formed by heat treatment in a magnetic field. Therefore, anisotropy of the recording magnetic film is weakened due to the heat treatment in a magnetic field conducted for fixing the fixed layer of the spin valve film in a preferable direction of the fixed magnetization.
Furthermore, when an upper magnetic pole is formed, the quality of a slope portion degrades due to oblique formation.
SUMMARY OF THE INVENTION
A magnetic film of the present invention includes a magnetic layer and an intermediate layer alternately formed, wherein the magnetic layer has a composition represented by (M 1 α 1 X 1 β 1 ) 100− δ 1 A 1 δ 1 (where α 1 , β 1 , and δ 1 represent % by atomic weight; M 1 is at least one magnetic metal selected from the group consisting of Fe, Co, and Ni; X 1 is at least one selected from the group consisting of Mg, Ca, Sr, Ba, Si, Ge, Sn, Al, Ga, and transition metals excluding the M 1 ; and A 1 is at least one selected from the group consisting of O and N), the magnetic layer has the following composition range:
0.1≦β 1 ≦12
α 1 +β 1 =100
0<δ 1 ≦10
the intermediate layer has a composition represented by (M 2 α 2 X 2 β 2 ) 100− δ 2 A 2 δ 2 (where α 2 , β 2 , and δ 2 represent % by atomic weight; M 2 is at least one magnetic metal selected from the group consisting of Fe, Co, and Ni; X 2 is at least one selected from the group consisting of Mg, Ca, Sr, Ba, Si, Ge, Sn, Al, Ga, and transition metals excluding the M 1 ; and A 2 is at least one selected from the group consisting of O and N), the intermediate layer has the following composition range:
0.1≦β 2 ≦80
α 2 +β 2 =100
δ 1 ≦δ 2 ≦67
In one embodiment of the present invention, the X 1 contains at least one selected from the group consisting of Si, Al, Ti, and V.
In another embodiment of the present invention, M 1 =M 2 and X 1 =X 2 .
In another embodiment of the present invention, A 2 contains O.
In another embodiment of the present invention, assuming that an average thickness of the magnetic layer is T 1 and an average thickness of the intermediate layer is T 2 , the following expressions are satisfied:
2 nm≦T 1 ≦150 nm
0.4 nm≦T 2 ≦15 nm
1≦T 1 /T 2 ≦50
In another embodiment of the present invention, the magnetic film satisfies the following expressions:
20 nm<T 1 ≦150 nm
1 nm<T 2 ≦15 nm
4≦T 1 /T 2 ≦50
at least 50% of magnetic crystal grains included in the adjacent magnetic layers via the intermediate layer spread across the intermediate layer.
A magnetic film of the present invention includes a magnetic layer and an intermediate layer alternately formed, wherein the magnetic layer has a composition represented by (M 1 α 1 X 1 β 1 ) 100− δ 1 A 1 δ 1 (where α 1 , β 1 , and δ 1 represent % by atomic weight, M 1 is at least one magnetic metal selected from the group consisting of Fe, Co, and Ni; X 1 is at least one selected from the group consisting of Mg, Ca, Sr, Ba, Si, Ge, Al, Ga, and transition metals including a IVa group, a Va group, and Cr; and Al is at least one selected from the group consisting of O and N), the magnetic layer has the following composition range:
0.1≦β 1 ≦12
α 1 +β 1 =100
0≦δ 1 ≦10
the intermediate layer has a composition represented by (M 2 α 2 X 2 β 2 ) 100− δ 2 A 2 δ 2 (where α 2 , β 2 , and δ 2 represent % by atomic weight, M 2 is at least one magnetic metal selected from the group consisting of Fe, Co, and Ni; X 2 is at least one selected from the group consisting of Mg, Ca, Sr, Ba, Si, Al, Ga, Ge, and transition metals including a IVa group, a Va group, and Cr; and A 2 is at least one selected from the group consisting of O and N), the intermediate layer has the following composition range:
0.1≦β 2 ≦80
α 2 +β 2 =100
δ 1 <δ 2 ≦67
In one embodiment of the present invention, the X 1 contains at least one selected from the group consisting of Si, Al, Ti, and V.
In another embodiment of the present invention, M 1 =M 2 and X 1 =X 2 .
In another embodiment of the present invention, A 2 contains O.
In another embodiment of the present invention, assuming that an average thickness of the magnetic layer is T 1 and an average thickness of the intermediate layer is T 2 , the following expressions are satisfied:
2 nm≦T 1 ≦150 nm
0.4 nm≦T 2 ≦15 nm
1≦T 1 /T 2 ≦50
In another embodiment of the present invention, the magnetic film satisfies the following expressions:
20 nm<T 1 ≦150 nm
1 nm<T 2 ≦15 nm
4≦T 1 /T 2 ≦50
at least 50% of magnetic crystal grains included in the adjacent magnetic layers via the intermediate layer spread across the intermediate layer.
A magnetic film of the present invention includes a magnetic layer and an intermediate layer alternately formed, wherein the magnetic layer has a composition represented by (M 1 α 1 X 1 β 1 Z 1 γ 1 ) 100− δ 1 A 1 δ 1 (where α 1 , β 1 , γ 1 , and δ 1 represent % by atomic weight; M 1 is at least one magnetic metal selected from the group consisting of Fe, Co, and Ni; X 1 is at least one selected from the group consisting of Mg, Ca, Sr, Ba, Si, Al, Ga, Ge and transition metals including a IVa group, a Va group, and Cr; Z 1 is at least one selected from the group consisting of Zn, Rh, Ru, and Pt; and A 1 is at least one selected from the group consisting of O and N), the magnetic layer has the following composition range:
0.1≦β 1 ≦12
0.1≦γ 1 ≦8
α 1 +β 1 +γ 1 =100
0≦δ 1 ≦10
the intermediate layer has a composition represented by (M 2 α 2 X 2 β 2 Z 2 γ 2 ) 100− δ 2 A 2 δ 2 (where α 2 , β 2 , γ 2 , and δ 2 represent % by atomic weight, M 2 is at least one magnetic metal selected from the group consisting of Fe, Co, and Ni; X 2 is at least one selected from the group consisting of Mg, Ca, Sr, Ba, Si, Al, Ga, Ge, and transition metals including a IVa group, a Va group, and Cr; Z 2 is at least one selected from the group consisting of Rh, Ru, and Pt; and A 2 is at least one selected from the group consisting of O and N), the intermediate layer has the following composition range:
0.1≦β 2 ≦80
0.1≦γ 2 ≦80
α 2 +β 2 +γ 2 =100
δ 1 <δ 2 ≦67
In one embodiment of the present invention, the X 1 contains at least one selected from the group consisting of Si, Al, Ti, and V.
In another embodiment of the present invention, M 1 =M 2 and X 1 =X 2 .
In another embodiment of the present invention, A 2 contains O.
In another embodiment of the present invention, assuming that an average thickness of the magnetic layer is T 1 and an average thickness of the intermediate layer is T 2 , the following expressions are satisfied:
2 nm≦T 1 ≦150 nm
0.4 nm≦T 2 ≦15 nm
1≦T 1 /T 2 ≦50
In another embodiment of the present invention, the magnetic film satisfies the following expressions:
20 nm<T 1 ≦150 nm
1 nm<T 2 ≦15 nm
4≦T 1 /T 2 ≦50
at least 50% of magnetic crystal grains included in the adjacent magnetic layers via the intermediate layer spread across the intermediate layer.
A high-resistant magnetic film of the present invention has a composition represented by M α X β (N δ O ε)γ (where α, β, γ, δ, and ε represent % by atomic weight; M is at least one magnetic metal selected from the group consisting of Fe, Co, and Ni; X is at least one selected from the group consisting of Mg, Ca, Sr, Ba, Si, Ge, Sn, Al, Ga, and transition metals excluding the M), wherein assuming that a chemical formula when the X forms a nitride with a lowest nitride generation free energy is XN m , and a chemical formula when the X forms an oxide with a lowest oxygen generation free energy is XO n , the high-resistant magnetic film has the following composition range:
α+β+γ=100
45≦α≦78
δ+ε=100
1<100×γ/β/(m×δ+n×ε)<2.5
the high-resistant magnetic film contains crystal grains, and a shortest diameter of each of the crystal grains is 20 nm or less.
A magnetic multilayer with high resistivity of the present invention includes a magnetic layer and an intermediate layer alternately formed, wherein the magnetic layer includes a high-resistant magnetic film, the high-resistant magnetic film and the intermediate layer have compositions represented by M 1m1 X 1n1 A 1q1 and M 2m2 X 2n2 A 2q2 , respectively (where m1, n1, q1, m2, n2, and q2 represent % by atomic weight; M 1 and M 2 are at least one magnetic metal selected from the group consisting of Fe, Co, and Ni; X 1 and X 2 are at least one selected from the group consisting of Mg, Ca, Sr, Ba, Si, Ge, Sn, Al, Ga, and transition metals excluding the magnetic metal; and A 1 and A 2 represent at least one selected from the group consisting of O and N), and the high-resistant magnetic film and the intermediate layer satisfy the following expressions:
M 1 =M 2 , X 1 =X 2
q1<q2
A method for producing a high-resistant layer of the present invention, includes the steps of: forming a low-resistant layer containing 10% by atomic weight or more of at least one element selected from the group consisting of Mg, Ca, Sr, Ba, Si, Ge, Sn, Al, Ga, and transition metals excluding the M 1 on either one of a magnetic thin film and a magnetic layer; and oxidizing or nitriding the low-resistant layer in an atmosphere selected from the group consisting of oxygen, nitrogen, oxygen plasma, and nitrogen plasma.
In one embodiment of the present invention, the magnetic thin film or the magnetic layer contains an element compatible with oxygen.
A magnetic multilayer of the present invention includes a magnetic thin film and a high-resistant layer alternately formed, wherein assuming that an average thickness of the magnetic thin film is T 3 , and an average thickness of the high-resistant layer is T 4 the following expressions are satisfied:
100 nm≦T 3 ≦1000 nm
2 nm≦T 4 ≦50 nm
10≦T 3 /T 4 ≦500
In one embodiment of the present invention, the magnetic thin film includes a magnetic layer and an intermediate layer, the magnetic layer, the intermediate layer, and the high-resistant layer have compositions represented by M 1 X 1 A 1 , M 2 X 2 A 2 , and M 3 X 3 A 3 , respectively (where M 1 to M 3 are at least one magnetic metal selected from the group consisting of Fe, Co, and Ni; X 1 , X 2 , and X 3 are at least one selected from the group consisting of Mg, Ca, Sr, Ba, Si, Ge, Sn, Al, Ga, and transition metals excluding the magnetic metal; and A 1 , A 2 , and A 3 are at least one selected from the group consisting of O and N), and the magnetic layer, the intermediate layer, and the high-resistant layer at least satisfy the conditions: M 1 =M 2 =M 3 , and X 1 =X 2 =X 3 .
A thin film head of the present invention includes an upper magnetic pole and a lower magnetic pole, wherein the upper magnetic pole includes either one of a high-resistant magnetic film and a magnetic multilayer with high resistivity, having a specific resistance of 80 μΩcm or more, and either one of a magnetic thin film and a magnetic multilayer, the upper magnetic pole and the lower magnetic pole form a recording gap, and either one of the magnetic thin film and the magnetic multilayer is formed at least in the vicinity of the recording gap at an end of the upper magnetic pole.
In one embodiment of the present invention, either one of the magnetic thin film and the magnetic multilayer is formed at least in the recording gap, and either one of the high-resistant magnetic film and the magnetic multilayer with high resistivity, having a specific resistance of 80 μΩcm or more is formed on either one of the magnetic thin film and the magnetic multilayer.
A method for producing a thin film of the present invention, includes: a first step of moving a substrate onto which a film is formed and a source for supplying material for forming a film in a relative manner; and a second step of forming at least one of a magnetic thin film, a magnetic multilayer, a high-resistant magnetic film, and a magnetic multilayer with high resistivity, wherein at least one magnetization difficult axis of the magnetic thin film, the magnetic multilayer, the high-resistant magnetic film, and the magnetic multilayer with high resistivity is formed in a movement direction in which the substrate and the source are moved in a relative manner.
In one embodiment of the present invention, the movement direction includes a depth direction of an upper magnetic pole of a thin film head.
In another embodiment of the present invention, the first step includes forming a film by a vapor growth method for generating a magnetic field of 50 Oe or more which is substantially orthogonal to the movement direction, substantially parallel to a film formation surface on the substrate, substantially uniform, and substantially in one direction.
In another embodiment of the present invention, the first step includes forming a film by changing a concentration of oxygen, oxygen plasma, nitrogen, or nitrogen plasma in a vapor growth apparatus.
In another embodiment of the present invention, a temperature of the substrate during formation of a film is substantially 300° C. or less.
A hard disk drive using the above-mentioned magnetic film as a magnetic pole.
A hard disk drive using the above-mentioned magnetic film as a part of a shield.
A hard disk drive using the above-mentioned high-resistant magnetic film as a magnetic pole.
A hard disk drive using the above-mentioned high-resistant magnetic film as a part of a shield.
A hard disk drive using the above-mentioned magnetic multilayer with high resistivity as a magnetic pole.
A hard disk drive using the above-mentioned magnetic multilayer with high resistivity as a part of a shield.
A hard disk drive using the above-mentioned magnetic multilayer as a magnetic pole.
A hard disk drive using the above-mentioned magnetic multilayer as a part of a shield.
A hard disk drive using the above-mentioned thin film head.
According to an aspect of the present invention, a magnetic film having outstanding soft magnetic characteristics at a high frequency and high Bs can be obtained for the following reason. Magnetic layers are magnetically separated by an intermediate layer, whereby the magnetic layers disposed via the intermediate layer decrease domain wall energy due to their magnetostatic binding or the intermediate layer suppresses the growth of magnetic crystal grains so as to refine them. Thus, apparent crystal magnetic anisotropy is decreased (so-called refining effect), which enhances soft magnetic characteristics.
Furthermore, even in the case where the thickness and width of a film have a high aspect ratio during refining of the film, shape anisotropy magnetic energy in a direction perpendicular to the film is suppressed, so that outstanding high-frequency characteristics can be exhibited. Particularly, in the case where a magnetic film of magnetostatic binding type is used in the vicinity of a recording gap of an upper magnetic pole of a thin film head, the magnetization of magnetic layers separated by an intermediate layer causes magnetostatic binding on the side face of the magnetic pole, and is likely to be directed in a preferable magnetization direction similarly to the case where apparent uniaxial anisotropy is formed; therefore, high-frequency characteristics are enhanced without conducting heat treatment in a magnetic field or forming a film in a magnetic field.
M 1 may be any of Fe, a FeCo alloy, and a FeCoNi alloy. X 1 contained in a magnetic layer has at least one effect such as enhancing corrosion resistance, refining crystal grains of magnetic metal, decreasing crystal magnetic anisotropy of magnetic crystal grains, and decreasing magnetostriction, as long as its amount is at least about 0.1%. Zn, Pt, Rh, Ru, and the like enhance corrosion resistance, Cr, Ge, Ga, V, Al, Si, Ti, and Mo decrease crystal magnetic anisotropy, and Ti, Si, and Sn decrease magnetostriction, for example, in the case where M 1 is Fe. Although one kind of M 1 has an effect, two or more kinds of M 1 will have more remarkable effect of decreasing a crystal grain diameter. Furthermore, the addition of Al further decreases a crystal grain diameter, which has an effect of enhancing soft magnetic characteristics. If β 1 is more than about 12%, and δ 1 is more than about 10%, Bs is decreased, which is not preferable.
An intermediate layer contains transition metal. Therefore, even when RIE involving generation of carbonyl of transition metal is used, a fine pattern can be relatively easily formed. In terms of processability, it is preferable that transition metal such as Cr and Pt is used for an intermediate layer. In terms of suppressing an eddy current loss between layers, a high-resistant oxide such as SiO 2 Al 2 O 3 is preferably used. The intermediate layer of the present invention uses an oxide, a nitride, or material consisting of an oxide and a nitride having relatively small energy of dissociation, so that the intermediate layer allows a high resistance to such a degree as to realize relatively satisfactory processability and sufficiently suppress an eddy current.
Furthermore, X 2 contained in the intermediate layer forms a reactive product with A 2 to promote separation from the magnetic layer. X 2 also has an outstanding effect on magnetostatic binding and refining crystal grains, even in the case where the intermediate layer of the present invention has a composition or a thickness which does not suppress an eddy current. X 2 exhibits its effect in an amount of about 0.1% or more. When the amount is more than about 80%, processability for patterning to a fine shape becomes poor or magnetic degradation is caused due to internal stress or strain.
It is required that δ 2 contains an O or N concentration higher than that of 67 1 . When the δ 2 concentration exceeds about 67%, excess oxygen or nitrogen gas is discharged from the intermediate layer in the course of heat treatment at a temperature higher than a film formation temperature, which may damage a film. Thus, the δ 2 concentration is about 67% or less.
In the magnetic thin film with the above-mentioned structure where M 1 =M 2 and X 1 =X 2 , by using an intermediate layer having the same element as that of the magnetic layer, interface energy occurring between the intermediate layer and the magnetic layer is suppressed. Therefore, magnetoelastic energy caused by internal stress generated on the interface and anisotropy energy in the film can be decreased. As a result, a magnetic film having outstanding soft magnetic characteristics and high Bs can be obtained. Furthermore, in the case where the intermediate layer of the magnetic thin film with the structure of the present invention has a thickness sufficient for realizing magnetostatic binding, vertical magnetization generated by interface strain can be suppressed; therefore, a domain structure is realized in which magnetostatic binding works more effectively.
Furthermore, interface energy is relatively low. Therefore, it is not required to form a film at a high temperature for the purpose of removing strain energy during film formation or after film formation, or to conduct heat treatment for removing strain at a high temperature. This allows soft magnetic characteristics to be easily obtained by a process at a low temperature (about 300° C. or less). Furthermore, in the case where layers of different materials are formed, when materials with low interface energy are combined, inter-layer peeling is likely to be caused. However, according to the present invention, the element common to the magnetic layer and the intermediate layer functions as glue, so that the layered film of the present invention has high strength. Furthermore, since M 1 =M 2 and X 1 =X 2 are satisfied, in the case where a vapor deposition, for example, is used, one source for supplying film formation material suffices to easily form a film. In the case of the structure of the present invention, even when the composition of each magnetic layer and intermediate layer is continuously varied, the same effect can be obtained.
According to another aspect of the present invention, X 2 contained in the intermediate layer is capable of easily generating a reaction product with A 2 , due to its low oxide generation free energy. Thus, even when the intermediate layer is relatively thin, it has appropriate separation effect between the magnetic layers.
According to still another aspect of the present invention, at least one selected from the group consisting of Rh, Ru, and Pt is added to the magnetic layer and the intermediate layer, respectively, whereby corrosion resistance of thin film material is remarkably enhanced. The content of these elements of about 0.1% or more is effective, whereas the content of about 8% or more will decrease a saturated magnetic flux density, and degrade soft magnetic characteristics.
Furthermore, in the magnetic thin film with the above-mentioned structure in which X 1 is at least one selected from the group consisting of Si, Al, Ti, and V, in the case where a trace amount of Si, Al, Ti, and V is contained in crystal grains included in the magnetic layer, crystal magnetic anisotropy energy is decreased. This results in a refining effect and a decrease in domain wall energy. Thus, more outstanding soft magnetic characteristics can be obtained. When these elements react with O or N in the magnetic layer, the growth of crystal grains is suppressed, and a refining effect is enhanced. In the case where these elements are contained in the intermediate layer, since any of these elements has large free energy for generating an oxygen or a nitrogen and has a large diffusion constant, the intermediate layer can be effective with a relatively small thickness. Such a relatively thin intermediate layer allows the magnetostatic binding between the magnetic layers to strengthen; therefore, a decrease in domain wall energy is large, and a decrease in a saturated magnetic flux density in the entire film caused by the intermediate layer is small.
In the magnetic thin film with the above-mentioned structure in which A 2 contained in the intermediate layer is O, the intermediate layer has particularly high thermal stability. Therefore, for example, even in the case where a heat treatment temperature in a magnetic field required for fixing an antiferromagnetic film of a spin valve film in an operation environment of an HDD is relatively high, soft magnetic characteristics will not degrade.
According to still another aspect of the present invention, outstanding soft magnetic characteristics and high Bs can be obtained. This may be because soft magnetic characteristics are exhibited by a kind of refining effect of magnetic crystal grains.
The magnetic layer is composed of crystal grains containing a trace amount of amorphous material, and adjacent magnetic layers are not required to be completely separated by the intermediate layer. Even when crystal grains in the magnetic layers interposing the intermediate layer therebetween are observed to be partially continued crystallographycally, magnetic strength of crystal grains of in-plane portions of the film is different from that in a direction perpendicular to the film passing through the intermediate layer.
Therefore, even when the magnetic thin film is refined, for example, as a magnetic pole of a thin film head, outstanding soft magnetic characteristics can be exhibited at a high frequency without being influenced by shape anisotropy in a direction perpendicular to the film. Soft magnetic characteristics become particularly outstanding, when the intermediate layer is composed of amorphous material or microcrystal containing amorphous material. When the thickness of the magnetic layer is about 2 nm or less, magnetic characteristics degrade. When the thickness of the magnetic layer is about 20 nm or more, grains are likely to excessively grow. Furthermore, unless the thickness of the intermediate layer is about 0.4 nm or more, crystal grains cannot be effectively refined. Unless the thickness of the intermediate layer is about 2 nm or less, soft magnetic characteristics degrade. This may be because exchange binding between the magnetic layers is weakened. Furthermore, in terms of Bs, the ratio of film thickness is preferably 1≦T 1 /T 2 ≦50.
According to still another aspect of the present invention, high Bs as well as outstanding soft magnetic characteristics at a high frequency can be obtained. This may be because of a kind of magnetostatic binding effect. The magnetic layer is composed of crystal grains or crystal grains containing a trace amount of amorphous material.
The magnetic layers are not required to be electrically insulated by the intermediate layer. When the thickness of the magnetic layer is about 20 nm or less, or larger than about 150 nm, magnetostatic binding becomes less effective. When the thickness of the intermediate layer is about 2 nm or less, the magnetic layers cannot be sufficiently separated, and exchange binding therebetween becomes strong. When the thickness of the intermediate layer exceeds about 15 nm, the distance between the magnetic layers becomes large, which results in that sufficient magnetostatic binding is unlikely to occur. If the shortest diameter of crystal grains included in the magnetic layer is about 20 nm or less which is sufficient for allowing a refining effect, in addition to magnetostatic binding, soft magnetic characteristics are further enhanced. The above-mentioned preferable thickness is considered to be determined in such a manner that the total of magnetostatic energy (which decreases due to magnetostatic binding of the magnetic thin film in a composition range of the present invention) and various energies (which are related to a domain structure resulting from a multi-layer structure). In terms of Bs, the ratio of film thickness is preferably 4≦T 1 /T 2 ≦50.
According to still another aspect of the present invention, a high-resistant layer has an effect of suppressing an eddy current, and compositions of the magnetic layer, the intermediate layer, and the high-resistant layer are close to each other. Therefore, interface energy occurring on an interface between different kinds of layers can be suppressed. This will decrease magnetostriction multiplied by strain energy, caused by an internal stress occurring on the interface, and anisotropic energy in the film.
Consequently, a magnetic film having outstanding soft magnetic characteristics and high Bs can be obtained even in the case where the total thickness is relatively large. Furthermore, interface energy is relatively low. Therefore, it is not required to form a film at a high temperature for the purpose of removing strain energy during film formation or after film formation, or to conduct heat treatment for removing strain at a high temperature. This allows soft magnetic characteristics to be easily obtained by a process at a low temperature (about 300° C. or less).
Furthermore, in the case of using vapor deposition, depending upon the composition of the magnetic film of the present invention, one source for supplying a film formation material suffices. Therefore, high-speed film formation can be conducted with a simple apparatus and satisfactory mass-productivity. Furthermore, in the case where layers of different materials are formed, when materials with low interface energy are combined, inter-layer peeling is likely to be caused. However, according to the present invention, the element common to the magnetic layer and the intermediate layer functions as glue, so that the layered film of the present invention has high strength.
According to the present invention, a high-resistant layer of a magnetic multilayer with the above-mentioned structure is produced by forming a low-resistant layer containing at least one selected from the group consisting of Mg, Ca, Sr, Ba, Si, Al, Ti, and Cr in an amount of about 10% by atomic weight or more on a magnetic thin film or a magnetic layer, and oxidizing or nitriding the low-resistant layer in an atmosphere of oxygen/oxygen plasma or nitrogen/nitrogen plasma. Thus, a high-resistant layer with a relatively small thickness and outstanding insulation can be produced. The low-resistant layer may be formed of either of Si, Al, Ti, and Cr, or may be formed of an alloy film thereof. Even when the low-resistant layer is formed of an alloy with magnetic transition metal such as Fe, an excellent high-resistant layer can be produced, as long as at least one of Mg, Ca, Sr, Ba, Si, Al, Ti, and Cr is contained in an amount of about 10% by atomic weight or more. A relatively thin insulation layer has outstanding magnetostatic binding characteristics, so that both high soft magnetic characteristics and outstanding high frequency characteristics can be obtained.
Furthermore, in a thin film head having a structure in which at least an upper magnetic pole is composed of a high-resistant magnetic film or a magnetic multilayer with high resistivity, having a specific resistance of about 80 μΩcm or more and a magnetic thin film or a magnetic multilayer with the above-mentioned structure, and the magnetic thin film or the magnetic multilayer is formed at least in the vicinity of a recording gap at an end portion of the upper magnetic pole, outstanding overwrite characteristics are exhibited at a high frequency even at a relatively low recording current. This is because of the following: high Bs material of the present invention is used for the end portion of the recording gap of a recording head in the upper magnetic pole where a magnetic flux with its core width narrowed is likely to be saturated, and a high-resistant magnetic film or a magnetic multilayer with high resistivity having a small loss of an eddy current is used for another portion of the upper magnetic pole for inducing a magnetic flux into the end portion of the recording gap.
The high-resistant film may be a layered film of a high-resistant layer and a magnetic layer, or may be a high-resistant single film in which a grain boundary of microcrystal grains considered to be granular is substantially surrounded by high-resistant amorphous material. It is important that the high-resistant film is a soft magnetic film with a specific resistance of about 80 μΩcm or more. When the present invention is applied to a lower magnetic pole as well as the upper magnetic pole, a recording current can be further decreased.
Furthermore, a thin film head with the above-mentioned structure, in which a magnetic thin film or a magnetic multilayer with the above-mentioned structure is formed at least on a recording gap, and a high-resistant magnetic film or a magnetic multilayer with high resistivity having a specific resistance of about 80 μΩcm or more is formed on the magnetic thin film or the magnetic multilayer, exhibits outstanding overwrite characteristics at a relatively low recording current. Such a thin film head can be produced by a simple process. The high-resistant film herein should also be a soft magnetic film with a specific resistance of about 80 μΩcm or more.
According to still another aspect of the present invention, a thin film head having outstanding high-frequency characteristics can be produced. This is because of the following: high-resistant material having the composition and structure of the present invention can suppress an eddy current loss, so that recording ability at a high frequency can be remarkably improved. A specific resistance of about 80 μΩcm or more is caused by a high-resistant X-O or N compound formed in a magnetic crystal grain boundary.
Furthermore, it is important that O and N should be contained in a range required for forming an X-O or N compound, represented by the above-mentioned expression. Soft magnetic characteristics are caused by microcrystal grains having the shortest diameter of about 20 nm or less. The microcrystal grains have a structure close to a needle-shape or a grain-shape.
According to still another aspect of the present invention, a thin film head having outstanding high-frequency characteristics can be produced. The above-mentioned high-resistant thin film comprises microcrystals having the shortest diameter of about 20 nm or less or comprises microcrystal and amorphous material. Therefore, a number of crystal grain boundaries are formed, and as a result, crystal grains do not move smoothly because of domain walls, and a domain wall resonance loss is increased.
However, in a layered structure of the present invention, a domain wall structure is changed so that magnetostatic energy of the entire film is decreased; as a result, domain wall energy is decreased, and a domain wall resonance loss at a high frequency is decreased. Furthermore, in the case where, due to a leakage magnetic field from the high-resistant magnetic film, magnetostatic binding occurs in the high-resistant magnetic film and in the magnetic thin film or the magnetic multilayer included in the upper magnetic pole, magnetostatic energy over the entire thin film head is decreased and high-frequency characteristics are enhanced.
Furthermore, since the composition of the magnetic layer is close to that of the intermediate layer, interface energy occurring on an interface between different kinds of layers can be suppressed. This will decrease magnetostriction multiplied by strain energy, caused by an internal stress occurring on the interface, and anisotropic energy in the film. Furthermore, in the case of using vapor deposition, depending upon the composition of the high-resistant magnetic film of the present invention, one source for supplying a film formation material suffices. Therefore, high-speed film formation can be conducted with a simple apparatus and satisfactory mass-productivity.
Furthermore, according to the present invention, a magnetic thin film (or magnetic multilayer) and a high-resistant magnetic film (or magnetic multilayer with high resistivity) are formed by vapor deposition while a positional relationship between a substrate and a source for supplying film formation material is changed during film formation, and a magnetization difficult axis of a thin film is formed in the direction of relative movement between the substrate and the source. In this method, uniaxial magnetic anisotropy formed in the thin film is determined mainly by a growth direction of magnetic crystal grains included in the magnetic film and the diameter of a fine crystal grain. Therefore, for example, even in the case where a heat treatment for fixing an antiferromagnetic film of a spin valve film in an operation environment of an HDD is conducted while a magnetic field is applied in a direction orthogonal to a direction of a magnetization easy axis of the magnetic thin film (or the magnetic multilayer) and the high-resistant magnetic film (or the magnetic multilayer with high resistivity), anisotropy is unlikely to be disturbed.
According to a method for producing a thin film for a thin film head in which a direction of relative movement is in a depth direction of an upper magnetic pole of the thin film head, a magnetization difficult axis which is stable against heat treatment is formed in the depth direction of the upper magnetic pole, and the film quality on a slope surface of the upper magnetic pole is improved. Therefore, a thin film head having outstanding recording characteristics can be produced.
In a magnetic thin film (or magnetic multilayer), a high-resistant magnetic film (or magnetic multilayer with high resistivity), and a thin film head with the above-mentioned structure formed by using a vapor growth method for generating a magnetic field of about 50 Oe or more which is substantially orthogonal to the movement direction, substantially parallel to a film formation surface on the substrate, substantially uniform, and substantially in one direction, the intensity of uniaxial anisotropy of the magnetic thin film (or the magnetic multilayer) and the high-resistant magnetic film (or the magnetic multilayer) is averaged. Thus, high-frequency characteristics are stabilized over the entire thin film head.
According to still another aspect of the present invention, a magnetic layer and an intermediate layer of a magnetic thin film; a magnetic layer, an intermediate layer, and a high-resistant layer of a magnetic multilayer; and a magnetic layer and an intermediate layer of a high-resistant magnetic film or a magnetic multilayer with high resistivity can be produced by using the same source for supplying film formation material. Therefore, a vapor growth apparatus can be miniaturized, and films can be formed at a high speed.
Furthermore, according to a method for producing a magnetic thin film, a magnetic multilayer, a high-resistant magnetic film, a magnetic multilayer with high resistivity, and a thin film head with the above-mentioned structure in which a substrate temperature is substantially about 300° C. or less, even a very thin intermediate layer (which cannot be used at a high temperature of about 500° C.) can be used. Because of a relatively low production temperature (about 300° C. or less), such a very thin intermediate layer does not have its structure changed due to heat diffusion. The very thin intermediate layer allows the strongest magnetostatic binding between magnetic layers disposed via the intermediate layer, as long as the magnetic thin film is of a magnetostatic binding type with the above-mentioned structure. Also, a very thin high-resistant layer which does not allow Bs to decrease can easily be formed. With a high Bs composition (i.e., with a composition in which a metal magnetic element ratio is large), crystal grains are likely to grow by heat treatment. However, since a production temperature is relatively low, crystal grains can easily be maintained in a fine state, and a magnetic thin film or a magnetic multilayer using the above-mentioned refining effect can easily be realized. Because of this, high Bs, a high resistance, and outstanding high frequency characteristics are realized, and a thin film head with high corrosion resistance caused by microcrystal and/or amorphous material can be provided.
Furthermore, in an HDD using, at least for a magnetic pole or a part of a shield, a magnetic thin film, a magnetic multilayer, a high-resistant magnetic film, or a magnetic multilayer with high resistivity having the above-mentioned structure, and in an information processing apparatus using such an HDD, a high recording density can be realized at a frequency of about 100 MHz or more. Thus, an apparatus can be miniaturized and rendered light-weight.
Furthermore, in an HDD using a thin film head with the above-mentioned structure and in an information processing apparatus using such an HDD, in addition to miniaturization of an apparatus and rendering an apparatus light-weight due to a high recording density, a power consumption can be reduced due to a decreased recording current. As a result, a battery of a portable information processing apparatus provided with the HDD can be miniaturized, and such a portable apparatus can be used continuously for a longer period of time.
Thus, the invention described herein makes possible the advantages of providing a soft magnetic material with high BS having outstanding high frequency characteristics and a method for producing the same.
These and other advantages of the present invention will become apparent to those skilled in the art upon reading and understanding the following detailed description with reference to the accompanying figures.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows magnetic characteristics of a magnetic film of Example 1 according to the present invention.
FIG. 2 shows magnetic characteristics of a magnetic film of Example 1 according to the present invention.
FIG. 3 shows magnetic characteristics of a magnetic film of Example 1 according to the present invention.
FIG. 4 shows magnetic characteristics of a magnetic film of Example 1 according to the present invention.
FIG. 5 shows magnetic characteristics of a magnetic film of Example 1 according to the present invention.
FIG. 6 shows magnetic characteristics of a magnetic film of Example 2 according to the present invention.
FIG. 7 shows magnetic characteristics of a magnetic film of Example 2 according to the present invention.
FIG. 8 shows magnetic characteristics of a magnetic film of Example 3 according to the present invention.
FIG. 9 shows magnetic characteristics of a magnetic film of Example 3 according to the present invention.
FIG. 10 shows magnetic characteristics of a magnetic film of Example 4 according to the present invention.
FIG. 11 shows magnetic characteristics of a magnetic film of Example 4 according to the present invention.
FIG. 12 shows magnetic characteristics of a magnetic film of Example 4 according to the present invention.
FIG. 13 shows magnetic characteristics of a magnetic film of Example 4 according to the present invention.
FIG. 14 shows magnetic characteristics of a magnetic film of Example 4 according to the present invention.
FIG. 15 shows magnetic characteristics of a magnetic film of Example 4 according to the present invention.
FIG. 16 shows magnetic characteristics of a magnetic film of Example 5 according to the present invention.
FIG. 17 shows magnetic characteristics of a magnetic film of Example 5 according to the present invention.
FIG. 18A illustrates a method for producing a high-resistant layer of Example 5 according to the present invention.
FIG. 18B illustrates a method for producing a high-resistant layer of Example 5 according to the present invention.
FIG. 18C illustrates a method for producing a high-resistant layer of Example 5 according to the present invention.
FIG. 18D illustrates a method for producing a high-resistant layer of Example 5 according to the present invention.
FIG. 18E is a flow chart of a method for producing a high-resistant layer of Example 5 according to the present invention.
FIG. 19A illustrates another method for producing a high-resistant layer of Example 5 according to the present invention.
FIG. 19B illustrates still another method for producing a high-resistant layer of Example 5 according to the present invention.
FIG. 19C illustrates still another method for producing a high-resistant layer of Example 5 according to the present invention.
FIG. 20 shows magnetic characteristics of a high-resistant magnetic film of Example 6 according to the present invention.
FIG. 21 shows magnetic characteristics of a high-resistant magnetic film of Example 6 according to the present invention.
FIG. 22 is a cross-sectional view of a conventional thin film head.
FIG. 23 is a schematic cross-sectional view of a thin film head using a magnetic film of Example 7 according to the present invention.
FIG. 24 is a schematic cross-sectional view of a thin film head using a magnetic multilayer with high resistivity of Example 7 according to the present invention.
FIG. 25 is a schematic cross-sectional view of a thin film head using a magnetic film and a magnetic multilayer with high resistivity of Example 7 according to the present invention.
FIG. 26 is a schematic cross-sectional view of a thin film head using a magnetic film and a magnetic multilayer with high resistivity of Example 7 according to the present invention.
FIG. 27 is a schematic cross-sectional view of a thin film head using a magnetic film and a magnetic multilayer with high resistivity of Example 7 according to the present invention.
FIG. 28 is a schematic cross-sectional view of a thin film head using a magnetic film and a magnetic multilayer with high resistivity of Example 7 according to the present invention.
FIG. 29 is a schematic cross-sectional view of a thin film head using a magnetic film and a magnetic multilayer with high resistivity of Example 7 according to the present invention.
FIG. 30 is a schematic cross-sectional view of a thin film head using a magnetic film and a magnetic multilayer with high resistivity of Example 7 according to the present invention.
FIG. 31 shows a structure of a magnetron sputtering device used in the method for producing a thin film of example 7 according to the present invention.
FIG. 32A illustrates a method for producing a thin film head using a magnetic film and a magnetic multilayer with high resistivity of Example 7 according to the present invention.
FIG. 32B illustrates a method for producing a thin film head using a magnetic film and a magnetic multilayer with high resistivity of Example 7 according to the present invention.
FIG. 32C illustrates a method for producing a thin film head using a magnetic film and a magnetic multilayer with high resistivity of Example 7 according to the present invention.
FIG. 33A illustrates another method for producing a thin film head using a magnetic film and a magnetic multilayer with high resistivity of Example 7 according to the present invention.
FIG. 33B illustrates still another method for producing a thin film head using a magnetic film and a magnetic multilayer with high resistivity of Example 7 according to the present invention.
FIG. 33C illustrates still another method for producing a thin film head using a magnetic film and a magnetic multilayer with high resistivity of Example 7 according to the present invention.
FIG. 34 shows overwrite characteristics of a thin film head of Example 7 according to the present invention.
FIG. 35A illustrates still another method for producing a thin film head using a magnetic film and a magnetic multilayer with high resistivity of Example 7 according to the present invention.
FIG. 35B illustrates still another method for producing a thin film head using a magnetic film and a magnetic multilayer with high resistivity of Example 7 according to the present invention.
FIG. 35C illustrates still another method for producing a thin film head using a magnetic film and a magnetic multilayer with high resistivity of Example 7 according to the present invention.
FIG. 36A illustrates still another method for producing a thin film head using a magnetic film and a magnetic multilayer with high resistivity of Example 7 according to the present invention.
FIG. 36B illustrates still another method for producing a thin film head using a magnetic film and a magnetic multilayer with high resistivity of Example 7 according to the present invention.
FIG. 36C illustrates still another method for producing a thin film head using a magnetic film and a magnetic multilayer with high resistivity of Example 7 according to the present invention.
FIG. 36D is a flow chart of still another method for producing a thin film head using a magnetic film and a magnetic multilayer with high resistivity of Example 7 according to the present invention.
FIG. 37 shows magnetic characteristics of a thin film head of Example 8 according to the present invention.
FIG. 38 is a side view of a hard disk apparatus of the present invention.
FIG. 39 is a plan view of the hard disk apparatus of the present invention.
FIG. 40 is a view illustrating a conventional thin film magnetic layer.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
A magnetic film having the structure and composition according to the present invention is most preferably formed by vapor deposition under a low gas pressure. There is no particularly preferential procedure for vapor deposition. However, for example, a magnetic film can be formed by sputtering such as RF magnetron sputtering, DC sputtering, opposed target sputtering, and ion beam sputtering, or reactive vapor deposition in which reactive gas is introduced into the vicinity of a substrate, and material for vapor deposition is dissolved. The present invention is practiced by sputtering as follows. A magnetic film, a magnetic multilayer, or a high-resistant magnetic film is formed on a substrate by subjecting an alloy target to sputtering in an atmosphere of an inactive gas. In this case, the alloy target is determined for its composition, considering the compositions of a magnetic layer and an intermediate layer included in the magnetic film, a magnetic layer, an intermediate layer and a high-resistant layer included in the magnetic multilayer, or a high-resistant magnetic film after being formed. Alternatively, a pellet for adding elements is placed over a metal target; under this condition, the metal target is subject to sputtering. Alternatively, a part of an additive in a gas state is doped in an apparatus (reactive sputtering). Thus, each layer should be successively formed to a required thickness. An electrode for discharging may be at least one depending upon the composition.
Herein, by controlling a discharge gas pressure, a discharge power, a substrate temperature, a bias state of a substrate, a magnetic field on a target and in the vicinity of a substrate, a target shape, a direction in which particles are incident upon a substrate, and the kind of discharge gas, a structure of a magnetic film, a thermal expansion coefficient, film characteristics obtained by a relative position between a substrate and a target, etc. can be regulated.
EXAMPLES
In the following examples, a magnetic film is produced by RF magnetron sputtering or DC magnetron sputtering. A substrate temperature is in a range of room temperature to about 100° C. This is because of the natural increase in temperature caused by energy during formation of films. Practically, it is possible to produce a preferable magnetic film as long as a substrate temperature is about 250° C. or less. A film structure is observed by X-ray diffraction (XRD) or a transmission electron microscope (TEM). A composition is analyzed by electron probe micro analysis (EPMA), and a coercivity and a saturated magnetic flux density are evaluated by a BH loop tracer and a vibration sample magnetometer (VSM), respectively. The composition of each layer such as an intermediate layer and a magnetic layer in the examples is indicated in terms of that of a single layer (about 3 μm) obtained under the condition of producing each layer.
Hereinafter, the present invention will be described by way of illustrative examples.
Example 1
The present example shows the results obtained by examining thicknesses of a magnetic layer (FeSi) and an intermediate layer (FeSiO) included in a magnetic film.
The experimental conditions are as follows:
Substrate: non-magnetic ceramic substrate
Substrate temperature: room temperature to about 100° C.
Target of a magnetic film: FeSi alloy target
Target size: about 3 inches
Discharge gas pressure: about 8 mTorr
Discharge electric power: about 300 W
Sputtering gas: Ar for a magnetic layer
Ar+O 2 for an intermediate layer (where an oxygen flow ratio O 2 /(Ar+O 2 ) is about 3% or about 25%)
The composition of a single layer obtained by using Ar alone in the present example is about Fe 94.0 Si 6.0 .
As shown in FIG. 1, it is preferable that Bs is about 1.5 T or more, and a coercivity is about 2.0 Oe or less. Depending upon the use, Bs may be less than about 1.5 T, or a coercivity may be larger than about 2.0 Oe.
FIGS. 1 through 4 show magnetic characteristics of FeSi/FeSiO magnetic films each obtained by using a FeSi alloy target in an atmosphere of Ar gas for a magnetic layer and Ar+O 2 (oxygen flow ratio is about 25%) for an intermediate layer, with varying thickness of the magnetic layer or the intermediate layer.
FIG. 5 shows the results obtained by changing the thickness of a magnetic layer in each FeSi/FeSiO magnetic film produced in an atmosphere of Ar+O 2 gas (oxygen flow ratio is about 3%) for an intermediate layer.
The cross-sections of films of Comparative Example ab and Example aa shown in FIG. 1 are observed with a TEM. In Comparative Example ab in which the intermediate layer is relatively thin, more than 50% magnetic crystal grains in a magnetic layer spread to an adjacent magnetic layer across an intermediate layer. In Example ba shown in FIG. 2 in which soft magnetic characteristics are satisfactory while the intermediate layer is relatively thin, many crystal grains in a magnetic layer spread to an adjacent magnetic layer across an intermediate layer. However, due to the small thickness ratio of the intermediate layer and the magnetic layer, soft magnetic characteristics over the entire film are more satisfactory than those in Comparative Example ab. As is understood from this, in a magnetic film including a relatively thick magnetic layer, it is important that at least 50% crystal grains spread across the intermediate layer, in addition to the small thickness ratio of the intermediate layer and the magnetic layer.
Any of the magnetic layers shown in FIGS. 1 to 4 contain crystal grains of about 10 nm or more, whereas any of the intermediate layers is amorphous or contains crystal grains of several nm.
In the present example, the magnetic film is subjected to pre-sputtering sufficiently during production of the magnetic layer and the intermediate layer. In addition to this, while the magnetic layer is formed by RF sputtering in an atmosphere of Ar gas, the intermediate layer is formed by intermittently introducing oxygen gas, whereby the magnetic layer and the intermediate layer are alternately formed continuously to obtain a magnetic thin film. It this case, it is found that about 1% to about 2% oxygen gas is added to the magnetic layer. The relationship in thickness between the intermediate layer and the magnetic layer in the magnetic thin film thus continuously produced is examined, which reveals that preferable soft magnetic characteristics can be obtained at the same thicknesses as those of the magnetic layer and the intermediate layer in the present example.
In the present example, FeSi and FeSiO are used for the magnetic layer and the intermediate layer, respectively. However, in the case where Fe contained in the magnetic layer or the intermediate layer is replaced by FeCo or FeCoNi, in the case where Si is replaced by at least one selected from the group consisting of Ge, Sn, Al, Ga, and transition metals (in particular, IVa group element, Va group element, or Cr), in the case where an appropriate amount or less of oxygen or nitrogen is added to the magnetic layer, or in the case where oxygen or nitrogen is appropriately added to the intermediate layer in an amount more than that in the magnetic layer, outstanding soft magnetic characteristics are obtained immediately after formation of the film to the completion of heat treatment (about 300° C.), with the same thicknesses of the magnetic layer and the intermediate layer as those in the present example.
In particular, regarding samples in which Si is replaced by Al, Ti, or V, high Bs as well as satisfactory soft magnetic characteristics are obtained. Furthermore, in the case where about 8% by atomic weight or less of Pt, Rh, or Ru is contained in elements excluding oxygen or nitrogen in the samples, corrosion resistance is enhanced.
The following is understood from the above-mentioned results.
Assuming that the average thickness of the magnetic layer is T 1 and the average thickness of the intermediate layer is T 2 , the magnetic films satisfying the expressions below can have outstanding soft magnetic characteristics and high Bs.
2 nm≦T 1 ≦150 nm
0.4 nm≦T 2 ≦15 nm
1≦T 1 /T 2 ≦150
In particular, among these magnetic films, those which satisfy the expressions below and in which at least 50% magnetic crystal grains in the magnetic layers disposed via the intermediate layer spread across the intermediate layer have outstanding high-frequency characteristics and allow magnetostatic binding to effectively occur.
20 nm<T 1 ≦150 nm
1 nm<T 2 ≦15 nm
4≦T 1 /T 2 ≦50
Example 2
The present example shows the results obtained by examining the added amounts of Si, O, and N in a magnetic layer of a magnetic film. The magnetic film of the present example includes a magnetic layer (FeSi(O)(N)) and an intermediate layer (FeSiO).
The experimental conditions are as follows:
Substrate: non-magnetic ceramic substrate
Substrate temperature: room temperature to about 100° C.
Target of a magnetic film: Fe or FeSi alloy target
Target size: about 3 inches
Discharge gas pressure: about 8 mTorr
Discharge electric power: about 300 W
Sputtering gas: Ar+(O 2 )+(N 2 ) for a magnetic layer
Ar+O 2 +(N 2 ) for an intermediate layer
As shown in FIG. 6, it is preferable that Bs is about 1.5 T or more, and a coercivity is about 2.5 Oe or less. Depending upon the use, Bs may be less than 1.5 T, or a coercivity may be larger than about 2.5 Oe.
FIG. 6 shows magnetic characteristics of Fe/FeO or FeSi/FeSiO magnetic films each obtained by using a Fe or FeSi alloy target. Herein, the magnetic layer is obtained by sputtering in an atmosphere of Ar gas and the intermediate layer is obtained by sputtering, using the same target as that in the magnetic layer, in an atmosphere of Ar+O 2 gas (oxygen flow ratio is about 25%). The thicknesses of the FeSi magnetic layer and the FeSiO intermediate layer are fixed to about 70 nm and about 5 nm, respectively.
FIG. 7 shows the results of FeSi(O)(N)/FeSiO magnetic films produced by varying the added amounts of oxygen and nitrogen in the magnetic layer. Herein, the magnetic layer is obtained by sputtering in an atmosphere of Ar+(O 2 )+(N 2 ) gas and the intermediate layer is obtained by sputtering, using the same target as that in the magnetic layer, in an atmosphere of Ar+O 2 +(N 2 ) gas (oxygen flow ratio is about 25%). The thicknesses of the FeSi magnetic layer and the FeSiO intermediate layer are fixed to about 100 nm and about 7 nm, respectively.
The above-mentioned values are all immediately after formation of the films. Any of the magnetic films of the present example show satisfactory soft magnetic characteristics even after heat treatment at about 300° C. It is understood from Comparative Example fa and Example fa shown in FIG. 6 that the addition of at least about 0.1% by atomic weight of Si will substantially enhance soft magnetic characteristics. Furthermore, it is understood from Examples and Comparative Examples shown in FIG. 7 that in the case where the added amount of Si is relatively small, the content of oxygen or nitrogen is preferably about 10% by atomic weight or less.
In the present example, FeSi(O)(N) and FeSiO are used for the magnetic layer and the intermediate layer, respectively. However, in the case where Fe in the magnetic layer or the intermediate layer is replaced by FeCo and FeCoNi, or in the case where Si is replaced by at least one of Ge, Sn, Al, Ga, and transition metals (in particular, IVa group element, Va group element, or Cr), outstanding soft magnetic characteristics are obtained immediately after formation of the film to the completion of heat treatment (about 300° C.), as long as the content of oxygen or nitrogen in the magnetic layer is in a preferable range of the present example, and the composition of metal or semi-metal added to magnetic metal is in a preferable range of the present example.
In particular, regarding samples in which Si is replaced by Al, Ti, or V, high Bs as well as satisfactory soft magnetic characteristics are obtained. Furthermore, in the case where about 8% by atomic weight or less of Pt, Rh, or Ru is contained in elements excluding oxygen or nitrogen in the samples, corrosion resistance is enhanced.
In summary, if the composition of the magnetic layer is expressed by (M 1 α 1 X 1 β 1 ) 100− δ 1 A 1 δ 1 (where α 1 , β 1 , and δ 1 represent % by atomic weight; M 1 is at least one magnetic metal selected from the group consisting of Fe, Co, and Ni; X 1 is at least one selected from the group consisting of Si, Ge, Sn, Al, Ga, and transition metals excluding M 1 ; A 1 is at least one selected from the group consisting of O and N), the composition is in a range represented as follows:
0.1≦β 1 ≦12
α 1 +β 1 =100
0≦δ 1 ≦10
Example 3
The present example shows the results obtained by varying the kind of intermediate layer.
FIG. 8 shows the compositions of intermediate layers, and soft magnetic characteristics of magnetic thin film produced by using the intermediate layers.
Herein, each magnetic layer is produced by sputtering in an atmosphere of Ar gas, and each intermediate layer is produced by sputtering, using the same target as that in the magnetic layer, in an atmosphere of Ar+(O 2 )+(N 2 ) gas. The composition of a FeSi magnetic layer is Fe 96.5 Si 3.5 , and has a thickness of about 10 nm. The thickness of each intermediate layer is fixed to about 2 nm.
The values shown in FIG. 8 are obtained by conducting heat treatment at about 250° C. in a vacuum. The intermediate layers containing oxygen or nitrogen have a large Si/Fe ratio. As is understood by comparing Example ha or hd with Comparative Example ha, soft magnetic characteristics are enhanced even by the addition of a trace amount of O or N. In Comparative Example hb, soft magnetic characteristics are not so unsatisfactory; however, surface roughness is caused after heat treatment. More specifically, it is found that the amount of oxygen or nitrogen contained in an intermediate layer should be more than that in a magnetic layer and 67% or less.
FIG. 9 shows the composition of each intermediate layer produced by using a target different from that in a magnetic layer, and soft magnetic characteristics of magnetic thin films obtained by using the intermediate layers. Each magnetic layer is produced by sputtering in an atmosphere of Ar gas. The composition of FeSi magnetic layer is Fe 96.5 Si 3.5 , and has a thickness of about 100 nm. Each intermediate layer is produced by sputtering in an atmosphere of Ar+(O 2 )+(N 2 ) gas so as to have each composition shown in FIG. 9 . The thickness of each intermediate layer is fixed to about 5 nm. FIG. 9 also shows a processing speed when each intermediate layer is etched by sputtering in an atmosphere of Ar gas at about 400 W and about 5 mTorr.
FIG. 9 shows the results obtained by conducting heat treatment at 250° C. in a vacuum after formation of the films. As is understood by comparing Examples with Comparative Examples, when the amount of Ti, Cr, V, Si, or Al with respect to Fe is increased, soft magnetic characteristics slightly degrade, and the processing speed of the intermediate layer is largely decreased. More specifically, when Ti, Cr, V, Si, or Al is added in an amount more than 4 times that of Fe, soft magnetic characteristics degrade and a processing speed is decreased.
In the present example shown in FIGS. 8 and 9, FeSi is used for the magnetic layer, and FeSi(O) (N) is used for the intermediate layer. However, even in the case where Fe in the intermediate layer is replaced by FeCo or FeCoNi, or even in the case where Si is replaced by at least one selected from the group consisting of Mg, Ca, Sr, Ba, Ge, Sn, Al, Ga, and transition metals (in particular, a IVa group, a Va group, or Cr) under the condition that the magnetic layer is in a preferable composition range as shown in Example 2, outstanding soft magnetic characteristics are obtained immediately after formation of a film to the completion of heat treatment at about 300° C., and an outstanding processing speed is obtained. In this case, it is required that the content of oxygen or nitrogen in the intermediate layer is in the same range as that in the present example, or the added amount of metal and semi-metal in the intermediate layer is 4 times or less that of magnetic metal.
In summary, if the composition of the intermediate layer of the magnetic thin film of the present invention is expressed by (M 2 α 2 X 2 β 2 ) 100− δ 2 A 2 δ 2 (where α 2 , β 2 , and δ 2 represent % by atomic weight; M 2 is at least one magnetic metal selected from the group consisting of Fe, Co, and Ni; X 2 is at least one selected from the group consisting of Si, Ge, Sn, Al, Ga, and transition metals excluding M 1 ; A 2 is at least one selected from the group consisting of O and N), the composition is in a range represented as follows:
0.1≦β 2 ≦80
α 2 +β 2 =100
δ 1 ≦δ 2 ≦67
Example 4
The present example shows the results obtained by examining the added elements contained in a magnetic layer.
The experimental conditions are as follows:
Substrate: non-magnetic ceramic substrate
Substrate temperature: room temperature to about 100° C.
Target of a magnetic film: complex target in which an element chip with metal or semi-metal shown in FIGS. 10 to 15 added thereto is placed on a Fe target. The same target is used for a magnetic layer and an intermediate layer.
Discharge gas pressure: about 8 mTorr
Discharge electric power: about 300 W
Sputtering gas: Ar+(O 2 )+(N 2 ) for a magnetic layer
Oxygen flow ratio O 2 /(Ar+O 2 ) is about 0% to about 1.5%
Nitrogen flow ratio N 2 /(Ar+N 2 ) is about 0% to about 5% (only magnetic layers with nitrogen added thereto)
Ar+O 2 +(N 2 ) for an intermediate layer
Oxygen flow ratio O 2 /(Ar+O 2 ) is fixed to be about 20%
Nitrogen flow ratio N 2 /(Ar+N 2 ) is about 0% to about 5% (only magnetic layers with nitrogen added thereto)
Sputtering gases with the above-mentioned flow ratios are alternately switched during formation of a film.
FIGS. 10 through 15 show soft magnetic characteristics of magnetic thin films and compositions of magnetic layers included in the magnetic thin films. A Fe single layer is listed as Comparative Example ja. The thickness of each magnetic layer is about 70 nm, and the thickness of each intermediate layer is about 5 nm. In the present example, it is confirmed, from Auger depth profile results obtained by continuously forming a magnetic layer and a non-magnetic layer while switching reactive gases during sputtering using the same target, that magnetic elements and added elements contained in the magnetic layer are added to the intermediate layer, and oxygen is added to the intermediate layer in an amount equal to or more than that in the magnetic layer. However, an exact composition of the intermediate layer is unclear.
Switching of reactive gases includes switching of power supplies to a plasma generation source, switching of a mixed ratio of argon inactive gas, switching of a discharge gas pressure during sputtering, switching of a sputtering power, and switching of a gas flow ratio.
The amount of elements of each magnetic layer shown in FIGS. 10 through 15 corresponds to that of a single layer (about 3 μm) formed under the condition of producing a magnetic layer. Actually, continuously formed magnetic layers are highly likely to contain an excess amount of oxygen of about 0% to about 3% by atomic weight due to the influence, for example, residual oxygen in the course of production of an intermediate layer.
By adding the additives as shown in FIGS. 10 through 15 and varying the amount of oxygen or nitrogen, a magnetic thin film having soft magnetic characteristics more outstanding than those of a Fe single layer can be obtained.
In the present example, the magnetic thin films which mainly contain Fe are examined. However, even in the case where Fe is replaced by FeCo or FeCoNi, outstanding soft magnetic characteristics are obtained immediately after formation of a film to the completion of heat treatment at about 300° C.
In summary, assuming that the composition of the intermediate layer of the magnetic thin film of the present invention is expressed by (M 2 α 2 X 2 β 2 ) 100− δ 2 A 2 δ 2 (where α 2 , β 2 , and δ 2 represent % by atomic weight; M 2 is at least one magnetic metal selected from the group consisting of Fe, Co, and Ni; X 2 is at least one selected from the group consisting of Mg, Ca, Sr, Ba, Si, Ge, Sn, Al, Ga, and transition metals excluding M 1 ; A 2 is at least one selected from the group consisting of O and N), when the composition is in a range represented as follows and M 1 =M 2 and X 1 =X 2 :
0.1≦β 2 ≦80
α 2 +β 2 =100
δ 1 ≦δ 2 ≦67
outstanding soft magnetic characteristics are obtained.
Furthermore, according to the method for producing a magnetic thin film of the above-mentioned structure by changing the concentration of oxygen/oxygen plasma or nitrogen/nitrogen plasma in a vapor growth apparatus as in the present example, a magnetic layer and an intermediate layer of a magnetic thin film, a magnetic layer, an intermediate layer and a high-resistant layer of a magnetic multilayer, and a magnetic layer and an intermediate layer of a high-resistant magnetic film can be produced by using the same source for supplying film formation material. This allows miniaturization of a growth apparatus and high-speed formation of a film.
Example 5
In the present example, a magnetic thin film and a high-resistant layer are formed on top of the other. The results obtained by examining the composition and thickness of a high-resistant layer in a magnetic multilayer will be shown.
First, a magnetic layer, an intermediate layer, and a high-resistant layer are examined in the case of using the same target.
The experimental conditions are as follows:
Substrate: non-magnetic ceramic substrate
Substrate temperature: room temperature to about 100° C.
Target of a magnetic multilayer: FeSiAl alloy target for a magnetic layer, an intermediate layer, and a high-resistant layer
Discharge gas pressure: about 8 mTorr
Discharge electric power: about 300 W
Sputtering gas: Ar for a magnetic layer
Ar+O 2 for an intermediate layer (where an oxygen flow ratio O 2 /(Ar+O 2 ) is about 20%)
Ar+O 2 for a high-resistant layer (where an oxygen flow ratio O 2 /(Ar+O 2 ) is about 20%), formed in a uniaxial magnetic field of about 100 Oe
The composition of a single layer produced in an atmosphere of Ar alone in the present example is about Fe 96.5 Si 3.0 Al 0.5 .
FIG. 16 shows soft magnetic characteristics obtained by changing the thickness of a magnetic thin film and the thickness of a high-resistant layer under the condition that the thickness of a magnetic layer is about 48.5 nm and the thickness of an intermediate layer is about 1.5 nm. The total thickness of each magnetic multilayer is about 4 μm.
In Examples shown in FIG. 16, each magnetic multilayer has a magnetic permeability of about 500 or more at about 100 MHz and about 400 or more at about 300 MHz, and has Bs of about 1.7 T or more. Each magnetic multilayer is provided with uniaxial anisotropy of about 5 Oe. In Examples qa through qd, it is considered that insulation is substantially eliminated in an intermediate layer of about 10 nm. On the other hand, in Comparative Example qd, it is considered that insulation between magnetic layers is not eliminated in an intermediate layer of about 1.5 nm due to the frequency dependence of magnetic permeability. Furthermore, in Comparative Examples qb and qc, it is easily understood that a high-resistant layer of about 50 nm sufficiently functions for insulation; however, sufficient magnetostatic binding does not occur in the magnetic thin film including a thick high-resistant layer, so that soft magnetic characteristics are poor and Bs is low.
Next, a magnetic multilayer is examined, in which a high-resistant layer is produced by using an Al or Si target under the condition that the same magnetic layer and intermediate layer as those described above are used.
The experimental conditions are the same as those in the above except for the conditions of producing a high-resistant layer. Only the differences will be shown below.
Comparative Example ra
Target: FeSiAl alloy target for a magnetic layer, an intermediate layer, and a high-resistant layer
Example ra
Target: FeSiAl alloy target for a magnetic layer and an intermediate layer
Al for a high-resistant layer
Example rb
Target: FeSiAl alloy target for a magnetic layer and an intermediate layer
Si for a high-resistant layer
Example rc
Target: FeSiAl alloy target for a magnetic layer and an intermediate layer
FeSiAl alloy target and Al target are simultaneously discharged for a high-resistant layer
Sputtering gas:
High-resistant layer of Comparative Example ra: Ar+O 2 (where an oxygen flow ratio O 2 /(Ar+O 2 ) is about 20%)
High-resistant layer of Example ra: an Al layer (low-resistant layer) is oxidized in an atmosphere of oxygen plasma
High-resistant layer of Example rb: a Si layer (low-resistant layer) is oxidized in an atmosphere of oxygen plasma
High-resistant layer of Example rc: a Fe 90 Si 3 Al 7 layer (low-resistant layer) produced by simultaneous discharge is oxidized in an atmosphere of oxygen plasma
The above-mentioned high-resistant layers are formed in a uniform magnetic field of about 100 Oe.
FIG. 17 shows soft magnetic characteristics depending upon the kind of a high-resistant layer under the conditions that the thickness of a magnetic layer is about 48.5 nm, the thickness of an intermediate layer is about 1.5 nm, the thickness of a magnetic thin film is about 500 nm, and the total thickness of a magnetic multilayer is about 4 μm.
Any film shown in FIG. 17 is provided with uniaxial anisotropy of about 13 to about 14 Oe. In Comparative Example ra, a high-resistant layer is produced by introducing oxygen during formation of a film; however, the high-resistant film does not sufficiently insulate magnetic thin films due to the frequency characteristics of magnetic permeability. This may be caused by the following: the high-resistant film does not have sufficiently high resistance as being an oxide film mainly containing Fe. Furthermore, in any of the magnetic multilayer of Examples shown in FIG. 17, the high-resistant layer insulates magnetic thin films, and a magnetic permeability is increased. This may be because an electrostatic binding effect is exhibited due to small thickness of the high-resistant layer. Soft magnetic characteristics of Example rc are more outstanding than those of Examples ra and rb.
In summary, assuming that magnetic thin films and a high-resistant layer are alternately formed, and the thickness of the magnetic thin film is T 3 and the thickness of the high-resistant layer is T 4 , a magnetic multilayer which satisfies the following conditions will have outstanding high-frequency characteristics and high Bs.
100 nm≦T 3 ≦1000 nm
2 nm≦T 4 ≦50 nm
10≦T 3 /T 4 ≦500
In the magnetic multilayer, assuming that the magnetic layer, the intermediate layer, and the high-resistant layer have compositions represented by M 1 X 1 A 1 , M 2 X 2 A 2 , and M 3 X 3 A 3 , respectively (M 1 , M 2 , and M 3 are at least one magnetic metal selected from the group consisting of Fe, Co, and Ni; X 1 , X 2 , and X 3 are at least one selected from the group consisting of Mg, Ca, Sr, Ba, Si, Ge, Sn, Al, Ga, and transition metals excluding the magnetic metal; A 1 to A 3 represent at least one selected from the group consisting of O and N), when the conditions: M 1 =M 2 =M 3 and X 1 =X 2 =X 3 are satisfied, outstanding soft magnetic characteristics and high Bs can be obtained even in the case where the total film thickness is relatively large.
According to a method for producing a high-resistant layer of the magnetic multilayer with the above-mentioned structure, including the steps of: forming a low-resistant layer containing at least one selected from the group consisting of Mg, Ca, Sr, Ba, Si, Ge, Sn, Al, and Ga in an amount of about 10% by atomic weight or more on a magnetic thin film or a magnetic layer; and oxidizing or nitriding the low-resistant layer in an atmosphere of oxygen/oxygen plasma or nitrogen/nitrogen plasma, a high-resistant layer which is relatively thin and has outstanding insulation characteristics can be produced. The low-resistant layer may be made of one of Mg, Ca, Sr, Ba, Si, Ge, Sn, Al and Ga, or may be an alloy layer thereof. For example, the low-resistant layer may be made of Al, Si, an AlTi alloy, or a Fe 90 Si 10 alloy. Particularly, an element selected from the group consisting of Si, Al, Ti, and Cr is likley to be dissolved in a solid state with magnetic metal. Thus, such an element is preferable in the case where the low-resistant layer is made of a magnetic alloy.
Referring to FIGS. 18A through 18E and FIGS. 19A through 19C, a method for producing a high-resistant layer will be described. FIGS. 18A through 18D illustrate a method for producing a high-resistant layer. FIG. 18E is a flow chart illustrating a method for producing a high-resistant layer. FIGS. 19A through 19C illustrate another method for producing a high-resistant layer.
Referring to FIGS. 18A through 18E, a magnetic thin film 182 is formed on a substrate 181 (FIG. 18 A). A low-resistant layer 183 containing at least one of Mg, Ca, Sr, Ba, Si, Ge, Sn, Al, Ga, and transition metals excluding the above-mentioned M 1 in an amount of about 10% by atomic weight is formed on the magnetic thin film 182 (FIG. 18B, Step S 181 in FIG. 18 E).
The low-resistant layer 183 is oxidized or nitrided in an atmosphere of oxygen, nitrogen, oxygen plasma, and nitrogen plasma, whereby a high-resistant layer 183 A is formed (FIG. 18C, Step S 182 in FIG. 18 E).
The magnetic thin film 182 may be a magnetic layer. The magnetic thin film 182 and the high-resistant layer 183 A may be multi-layered by repeatedly, alternately forming the magnetic thin film 182 and the high-resistant layer 183 A on the high-resistant layer 183 A (FIG. 18 D).
Referring to FIGS. 19A through 19C, another method for producing a high-resistant layer will be described. The magnetic thin film or the magnetic layer may contain oxygen-compatible elements. A magnetic thin film 192 containing an oxygen-compatible element such as Si, Al, Ti, and Cr is formed on a substrate 191 (FIG. 19 A). A low-resistant layer 193 containing at least one selected from the group consisting of Mg, Ca, Sr, Ba, Si, Ge, Sn, Al, Ga, and transition metals excluding the above-mentioned M 1 in an amount of about 10% by atomic weight or more is formed on the magnetic thin film 192 .
The low-resistant layer 193 is oxidized or nitrided in an atmosphere of oxygen/oxygen plasma and nitrogen/nitrogen plasma, whereby a high-resistant layer 193 A is formed (FIG. 19 B).
The magnetic thin film 192 may be a magnetic layer. The magnetic thin film 192 and the high-resistant layer 193 may be multi-layered by repeatedly, alternately forming the magnetic thin film 192 and the high-resistant layer 193 on the high-resistant layer 193 (FIG. 19 C).
Example 6
The present example shows the results obtained by examining the composition of a high-resistant magnetic film with a resistivity of about 80 μΩcm or more and a magnetic multilayer with high resistivity obtained by layering high-resistant magnetic films.
The experimental conditions are as follows:
Substrate: non-magnetic ceramic substrate
Substrate temperature: room temperature to about 100° C.
Target: complex target in which a metal, semi-metal, or oxide chip is disposed on a Fe or FeCo target. The same target is used for a magnetic layer and an intermediate layer.
Discharge gas pressure: about 8 mTorr
Discharge electric power: about 300 W
Sputtering gas:
High-resistant magnetic film
Ar+(O 2 )+(N 2 ) (where oxygen flow ratio O 2 /(Ar+O 2 ) is about 0% to about 5%, and nitrogen flow ratio N 2 /(Ar+N 2 ) is about 20% (only high-resistant magnetic films with nitrogen added thereto)), formed in a uniform magnetic field of about 100 Oe
High-resistant magnetic multilayer
Magnetic layer: Ar+(O 2 )+(N 2 ) (where oxygen flow ratio O 2 /(Ar+O 2 ) is about 0% to about 5%, and nitrogen flow ratio N 2 /(Ar+N 2 ) is about 20% (only high-resistant magnetic films with nitrogen added thereto)), formed in a uniform magnetic field of about 100 Oe
Intermediate layer: Ar+O 2 (where oxygen flow ratio O 2 /(Ar+O 2 ) is fixed to be about 20%), formed in no magnetic field
Sputtering gases with the above-mentioned flow ratios are alternately switched during formation of a film.
FIG. 20 shows soft magnetic characteristics and compositions of high-resistant magnetic films after heat treatment at about 250° C. in a vacuum. The thickness of each high-resistant magnetic film is about 4 μm.
The high-resistant magnetic films of Examples shown in FIG. 20 exhibit a high resistance of about 80 μΩcm or more, although a resistivity is slightly decreased after heat treatment, compared with the case immediately after formation of the films. As is understood from the Examples shown in FIG. 20, when the high-resistant magnetic film is represented by M α X β (N δ Oε) γ (where α, β, γ, δ, and ε represent % by atomic weight; M is at least one magnetic metal selected from the group consisting of Fe, Co, and Ni; and X is at least one selected from the group consisting of Mg, Ca, Sr, Ba, Si, Ge, Sn, Al, Ga, and transition metals excluding the above-mentioned M), assuming that a chemical formula when X becomes a nitride having the lowest nitride generation free energy and a chemical formula when X becomes a nitride having the lowest oxide generation free energy, it is important that the following range should be satisfied:
α+β+γ=100
45≦α≦78
δ+ε=100
1<100×γ/β/(m×δ+n×ε)<2.5
Furthermore, the shortest diameter of an average crystal grain is about 20 nm or less.
Next, high-resistant magnetic films are used as magnetic layers, and intermediate layers are produced by using the same target as that of each high-resistant magnetic film with an oxygen flow ratio of about 20%. The magnetic layers each having a thickness of about 500 nm and the intermediate layers each having a thickness of about 500 nm are alternately formed to obtain magnetic multilayers. The magnetic multilayer with high resistivity is formed into strips with a width of about 1 μm and a length of about 1 mm by a focused ion beam (FIB), and the strips are measured for magnetic permeability at a high-frequency. Furthermore, as Comparative Examples, a high-resistant magnetic film is formed into the same shape as that of the magnetic multilayer, in which the thickness of each magnetic layer is about 100 nm and the thickness of each intermediate layer is about 5 nm. FIG. 21 shows soft magnetic characteristics obtained after heat treatment at about 250° C.
As is understood from the results shown in FIG. 21, a high-resistant magnetic film formed into a relatively minute shape exhibits an increased magnetic permeability at a high frequency by being layered on an intermediate layer having a higher oxygen concentration, and such a layered structure is effective for a magnetic device subjected to minute processing such as a thin film head.
As described above, a thin film head having more outstanding high-frequency characteristics can be produced by using a magnetic multilayer with high resistivity having a structure in which magnetic layers and intermediate layers are alternately formed. Each magnetic layer is made of a high-resistant magnetic film with the above-mentioned structure and has a composition represented by M 1m1 X 1n1 A 1q1 , and each intermediate layer has a composition represented by M 2m2 X 2n2 A 2q2 (where m1, n1, q1, m2, n2, and q2 represent % by atomic weight; M 1 and M 2 are at least one magnetic metal selected from the group consisting of Fe, Co, and Ni; X 1 and X 2 are at least one selected from the group consisting of Mg, Ca, Sr, Ba, Si, Ge, Sn, Al, Ga, and transition metals excluding the magnetic metal; and A 1 and A 2 are at least one selected from the group consisting of O and N); the following expressions are satisfied:
M 1 =M 2 , X 1 =X 2
q1<q2
In the present example, sputtering is used; however, the above-mentioned films can be produced by using reactive vapor deposition.
Example 7
The present example shows recording characteristics obtained by applying a magnetic thin film of the present invention to a recording magnetic pole of a thin film head.
The structure of a thin film head used in the present example is as follows:
Recording medium: about 2200 Oe
Recording gap: about 0.2 μm
Recording frequency: about 100 MHz
Number of turns: about 42
Thicknesses of upper and lower magnetic poles: about 4 μm each
Recording current: fixed to be about 5 mA
Permalloy (NiFe) deposited by plating is used for films of Comparative Examples. Each magnetic thin film of Examples includes the following layers: magnetic layers Fe 94.0 Si 6.0 (about 100 nm per layer) and intermediate layers: (Fe 0.93 Si 0.7 ) X O 100−X (about 5 nm per layer), and each magnetic multilayer with high resistivity includes the following layers: magnetic layers Fe 69 Mg 13 O 18 (about 100 nm per layer) and intermediate layers (Fe0.84Mg0.16) X O 100−X (about 5 nm per layer) where 18<X.
Referring to FIGS. 22 to 30 , a thin film head of the present example will be described. In the drawings, a magnetic thin film is represented by high Bs, and a magnetic multilayer are represented by high ρ.
FIG. 22 shows a structure of a thin film head 220 of Comparative Example ua (see FIG. 34 ). The thin film head 220 includes an upper magnetic pole 221 , a lower magnetic pole 222 , a shield film 223 , and a coil 224 . The upper magnetic pole 221 , the lower magnetic pole 222 , and the shield film 223 contain Ni 50 Fe 50 .
FIG. 23 shows a structure of a thin film head 230 of Example ua (see FIG. 34 ). The thin film head 230 includes an upper magnetic pole 231 , a lower magnetic pole 232 , a shield film 233 , and a coil 234 . The upper magnetic pole 231 , the lower magnetic pole 232 , and the shield film 233 respectively contain a magnetic thin film.
FIG. 24 shows a structure of a thin film head 240 of Example ub (see FIG. 34 ). The thin film head 240 includes an upper magnetic pole 241 , a lower magnetic pole 242 , a shield thin film 243 , and a coil 244 . The upper magnetic pole 241 , the lower magnetic pole 242 , and the shield film 243 respectively contain a magnetic multilayer.
FIG. 25 shows a structure of a thin film head 250 of Example uc (see FIG. 34 ). The thin film head 250 includes an upper magnetic pole 251 , a lower magnetic pole 252 , a shield film 253 , and a coil 254 . The upper magnetic pole 251 contains a magnetic thin film 251 B (thickness: about 0.5 μm), and a magnetic multilayer with high resistivity 251 A (thickness: about 3.5 μm). The lower magnetic pole 252 contains a magnetic thin film 252 B (thickness: about 0.5 μm), and a magnetic multilayer 252 A (thickness: about 3.5 μm). The shield film 253 contains a magnetic multilayer.
FIG. 26 shows a structure of a thin film head 260 of Example ud (see FIG. 34 ). The thin film head 260 includes an upper magnetic pole 261 , a lower magnetic pole 262 , a shield film 263 , and a coil 264 . The upper magnetic pole 261 contains a magnetic thin film 261 B (maximum thickness: about 4 μm), and a magnetic multilayer with high resistivity 261 A (maximum thickness: about 4 μm). The lower magnetic pole 262 contains a magnetic thin film 262 B (thickness: about 0.5 μm), and a magnetic multilayer with high resistivity 262 A (thickness: about 3.5 μm). The shield film 263 contains a magnetic multilayer with high resistivity.
FIG. 27 shows a structure of a thin film head 270 of Example ue (see FIG. 34 ). The thin film head 270 includes an upper magnetic pole 271 , a lower magnetic pole 272 , a shield film 273 , and a coil 274 . The upper magnetic pole 271 contains a magnetic thin film 271 B (thickness: about 0.5 μm) and a magnetic multilayer with high resistivity 271 A (thickness: about 3.5 μm). The lower magnetic pole 272 contains a magnetic thin film 272 B (thickness: about 0.5 μm), and a magnetic multilayer with high resistivity 272 A (thickness: about 3.5 μm). The shield film 273 is formed of a magnetic multilayer with high resistivity.
FIG. 28 shows a structure of a thin film head 280 of Example uf (see FIG. 34 ). The thin film head 280 includes an upper magnetic pole 281 , a lower magnetic pole 282 , a shield film 283 , and a coil 284 . The upper magnetic pole 281 contains a magnetic thin film 281 B (thickness: about 0.5 μm), and a magnetic multilayer with high resistivity 281 A (thickness: about 3.5 μm). The lower magnetic pole 282 is formed of a magnetic multilayer with high resistivity (thickness: about 4 μm). The shield film 283 is formed of a magnetic multilayer with high resistivity.
FIG. 29 shows a structure of a thin film head 290 of Example ug (see FIG. 34 ). The thin film head 290 includes an upper magnetic pole 291 , a lower magnetic pole 292 , a shield film 293 , and a coil 294 . The upper magnetic pole 291 contains a magnetic thin film 291 B (maximum thickness: about 4 μm), and a magnetic multilayer with high resistivity 291 A (maximum thickness: about 4 μm). The lower magnetic pole 292 is formed of a magnetic multilayer with high resistivity (thickness: about 4 μm). The shield film 293 is formed of a magnetic multilayer with high resistivity.
FIG. 30 shows a structure of a thin film head 300 of Example uh (see FIG. 34 ). The thin film head 300 includes an upper magnetic pole 301 , a lower magnetic pole 302 , a shield film 303 , and a coil 304 . The upper magnetic pole 301 contains a magnetic thin film 301 B (thickness: about 0.5 μm), and a magnetic multilayer with high resistivity 301 A (thickness: about 3.5 μm). The lower magnetic pole 302 is formed of a magnetic multilayer with high resistivity (thickness: about 4 μm). The shield film 303 is formed of a magnetic multilayer with high resistivity.
FIG. 31 shows a structure of a DC magnetron sputtering device 320 for producing films. The DC magnetron sputtering device 320 includes a rotator 361 which rotates with respect to a central axis 361 A. A substrate 250 onto which a film is formed is provided on the rotator 361 . The DC magnetron sputtering device 320 includes a high Bs vapor deposition source 261 BS for forming a high Bs film on the substrate 250 , and a high ρ vapor deposition source 261 AS for forming a high ρ film on the substrate 250 . A target size, a discharge gas pressure, and a substrate temperature are set to be about 5 inches, about 5 mTorr, and room temperature, respectively.
As shown in FIGS. 32A through 32C, for example, in the case of a thin film head 250 of Example uc, particularly when the upper magnetic pole 251 is formed on the coil 254 , the magnetic thin film 251 B (high Bs film) and the magnetic multilayer with high resistivity 251 A (high ρ film) are successively formed by using the high Bs vapor deposition source 251 BS and the high ρ vapor deposition source 251 AS.
As shown in FIGS. 33A through 33C, in the thin film head 260 of Example ud, the magnetic thin film 261 B (high Bs film) is formed on the front side of a recording gap, and the magnetic multilayer with high resistivity 261 A (high ρ film) is formed on the back side of the recording gap.
As shown in FIG. 34, compared with a thin film head using conventional magnetic poles made of permalloy, a thin film head using the magnetic thin film and the magnetic multilayer with high resistivity of the present invention as magnetic poles exhibits outstanding overwrite characteristics at a low recording current. This is due to the magnetic material used in the present invention, which has a high saturated magnetic flux density or high specific resistance, and has outstanding soft magnetic characteristics, with a domain structure controlled.
Accordingly, outstanding overwrite characteristics are exhibited at a relatively low recording current in a thin film head having a structure in which at least an upper magnetic pole is composed of a magnetic multilayer with high resistivity (specific resistance: about 80 μΩcm or more) and a magnetic thin film or a magnetic multilayer with high resistivity having the above-mentioned structure, and the magnetic thin film or the magnetic multilayer is formed at least in the vicinity of a recording gap at an end portion of the upper magnetic pole; and a thin film head having a structure in which a magnetic thin film or a magnetic multilayer with the above-mentioned structure is formed at least on a recording gap, and a magnetic multilayer with high resistivity (specific resistance: about 80 μΩcm or more) is formed on the magnetic thin film or the magnetic multilayer. These thin film heads can be obtained by a relatively easy process.
Example 8
The present example describes a method for producing a recording magnetic pole of a thin film head while changing a relative position between a thin film head and a target.
FIGS. 35A through 35C and FIGS. 36A through 36C illustrate other methods for producing a thin film head using a magnetic thin film and a magnetic multilayer with high resistivity of the present invention. FIG. 36D is a flow chart illustrating other methods for producing a thin film head using a magnetic thin film and a magnetic multilayer with high resistivity. In the present example, the DC magnetron sputtering device 320 shown in FIG. 31 is used, and a target size, a discharge gas pressure, and a substrate temperature are set to be about 5×15 inches, about 5 mTorr, and about 20° C., respectively.
In FIGS. 35A through 35C, FIGS. 36A through 36C, and FIG. 36D, Fe 94 Si 6 is used as target material. First, a target is fixed, and a substrate is reciprocated in a shorter direction of the target (S 361 ), whereby at least one of a magnetic thin film, a magnetic multilayer, a high-resistant magnetic film, and a magnetic multilayer with high resistivity is formed (S 362 ). Herein, the shorter direction refers to a depth direction DD (FIG. 35A) of an upper magnetic pole of a thin film head. A movement speed is set to be about 2 rpm, and a change angle of movement is in a range of about ±0° to about 45°. In the device used in the present example, when the change angle of movement of the substrate exceeds about 20° to about 30°, a film formation speed becomes about ⅕ or less that of the case where the change angle is 0°. More specifically, as the change angle increases, a distance between the target and the substrate is increased, and the number of sputtering particles scattering from the target to the substrate is greatly decreased.
The films thus obtained are examined for soft magnetic characteristics, and their cross-sectional structures are observed with a TEM. FIG. 37 shows the results.
As shown in FIG. 37, compared with the case where the relative position between the target and the substrate is fixed, in the case where the target is moved in a relative manner, a magnetization difficult axis of a film is formed in a direction in which the target is moved, and soft magnetic characteristics are enhanced. The direction of the magnetization difficult axis is not related to the direction of a leakage magnetic field on the target, and depends upon the method for forming a film of the present example. When the cross-section of the film of Comparative Example va is observed with a TEM, column-shaped or needle-shaped crystal grains are formed. On the other hand, when the cross-section of the film of Example vc is observed with a TEM, a layered structure of a microcrystalline layer of about 3 nm and an amorphous layer of about 1 to about 2 nm is formed. More specifically, in spite of the fact that films are formed under the same sputtering conditions, by changing a positional relationship between the substrate and the target in a particular direction, a film formation speed is changed in a cyclic manner, energy or an average free passage of sputtering particles incident upon the substrate is changed, an angle at which sputtering particles are incident upon the substrate is changed, and the like. As a result, the above-mentioned layered structure is naturally formed.
Furthermore, the amorphous layer contains more oxygen than the microcrystalline layer. Stress in a film obtained from a warpage amount of the substrate is decreased as the cycle of the layered structure becomes shorter. This is because films are formed with a large change angle at a constant movement speed.
Example 9
A hard disk drive using a thin film head of the present invention will be described with reference to FIGS. 38 and 39.
FIG. 38 is a side view of a hard disk drive 110 using a thin film head of the present example. FIG. 39 is a plan view thereof.
The hard disk drive 110 includes a slider 120 for holding a thin film head of the present invention, a head supporting mechanism 130 for supporting the slider 120 , an actuator 114 for tracking a thin film head via the head supporting mechanism 130 , and a disk drive motor 112 for driving a disk 116 . The head supporting mechanism 130 includes an arm 122 and a suspension 124 .
The disk drive motor 112 drives the disk 116 at a predetermined speed. The actuator 114 moves the slider 120 holding the thin film head in a radial direction across the surface of the disk 116 in such a manner that the thin film head can access a predetermined data track of the disk 116 . The actuator 114 is typically a linear or rotary voice coil motor.
The slider 120 holding the thin film head is, for example, an air bearing slider. In this case, the slider 120 comes into contact with the surface of the disk 116 upon boot-up or halting of the hard disk drive 110 . When information is recorded onto or reproduced from the hard disk drive 110 , the slider 120 is maintained on the surface of the disk 116 by an air bearing formed between the rotating disk 116 and the slider 120 . The thin film head held on the slider 120 records information onto or reproduces it from the disk 116 .
As described above, by using a magnetic thin film, a magnetic multilayer, a high-resistant magnetic film, and a magnetic multilayer with high resistivity having the composition and structure of the present invention, and a method for producing the same, it is possible to provide a magnetic material which has outstanding soft magnetic characteristics at a high frequency and has a high saturated magnetic flux density or a high specific resistance, even after being formed into a minute shape in a process at a low temperature (i.e., about 300° C. or less). Furthermore, the magnetic thin film and the magnetic multilayer have excellent processability to a minute shape, and can be layered at a high speed. Still further, these films can be provided with anisotropy without being heat-treated in a magnetic field. Therefore, mass-production and reliability of magnetic devices using these films are enhanced, and processing apparatuses and vapor growth apparatuses can be produced easily at a low cost.
Furthermore, by using the magnetic thin film, the magnetic multilayer, the high-resistant magnetic film, and the magnetic multilayer with high resistivity of the present invention, thin film heads for high-density recording, having outstanding mass-productivity can be obtained. In addition, the power consumption of an apparatus using such a thin film head can be decreased, so that an information processing apparatus can be miniaturized, rendered light-weight, and used continuously for a long period of time.
Various other modifications will be apparent to and can be readily made by those skilled in the art without departing from the scope and spirit of this invention. Accordingly, it is not intended that the scope of the claims appended hereto be limited to the description as set forth herein, but rather that the claims be broadly construed. | Magnetic film comprising a substantially crystalline magnetic layer and an intermediate layer alternately formed in contact with each other, wherein the magnetic layer has composition (M 1 α 1 X 1 β 1 ) 100−δ1 A 1 δ 1 (α 1 , β 1 , and δ 1 represent % by atomic weight; M 1 is at least one of Fe, Co, and Ni; X 1 is at least one of Mg, Ca, Sr, Ba, Si, Ge, Sn, Al, Ga, and transition metals excluding M 1 ; and A 1 is at least one of O and N), wherein:
0.1≦β 1 ≦12
α 1 +β 1 =100
0<δ 1 ≦10;
the intermediate layer has composition (M 2 α 2 X 2 β 2 ) 100−δ2 A 2 δ 2 (α 2 , β 2 , and δ 2 represent % by atomic weight; M 2 is at least one of Fe, Co, and Ni; X 2 is at least one of Mg, Ca, Sr, Ba, Si, Ge, Sn, Al, Ga, Ge and transition metals excluding the M 2 ; and A 2 is O), wherein:
0.1≦β 2 ≦80
α 2 +β 2 =100
δ 1 ≦δ 2 ≦67. | 2 |
BACKGROUND OF THE INVENTION
[0001] Increased utilization of solar power is highly desirable as solar power is a readily available renewable resource with power potential far exceeding total global needs; and as solar power does not contribute to pollutants associated with fossil fuel power, such as unburned hydrocarbons, NOx and carbon dioxide. Solar powerplants produce no carbon dioxide that contributes as a greenhouse gas to global warming-in sharp contrast to fossil fuel powerplants such as coal, oil and even natural gas powerplants. Limitations to the widespread deployment of solar power has largely been a consequence of higher power cost per kilowatt-hour for traditional solar power systems as compared with fossil fuel power systems, driven in large part by the cost to make these solar power systems.
BRIEF SUMMARY OF THE INVENTION
[0002] The present invention provides inventive development of inflatable heliostatic solar collector devices. More specifically, the present invention provides for low-cost inflatable heliostatic solar power collectors, which are stand-alone units suitable for use in small, medium, or utility scale applications, as opposed to prior art “power tower” concepts best suited for utility scale application. In one preferred embodiment the inflatable heliostatic power collector uses a reflective surface or membrane “sandwiched” between two inflated chambers, and an elongated linear solar power receiver which receives solar insolation reflected and concentrated by this reflective surface.
[0003] The power receiver includes a photovoltaic receiver and may optionally also include a solar thermal receiver element, in preferred embodiments of the invention. The utilization of modest concentration ratios enables benefits in both reduced cost and increased conversion efficiency, relative to simple prior-art flat plate solar panels using silicon solar cells.
[0004] In a preferred embodiment the inflatable structure includes inventive application of simple lightweight and low cost frame members, and polar axis heliostatic aiming for Sun tracking, using simple and low cost motorized pointing control means. The polar axis will typically be oriented in a North-South orientation, with a tilt corresponding to latitude or a value within 25 degrees of the latitude. Air or liquid cooling means will preferably be utilized to keep temperatures in the photovoltaic receiver from exceeding limit values. The invention is intended to provide great flexibility and value in tailored applications using varying numbers of the low-cost inflatable heliostatic power collectors, of varying scalable size designs, for optimal use in applications ranging from (i) one or a few units for private home installations on a rooftop or back-yard, to (ii) estate/farm/ranch/commercial building installations with a small/medium field of units, to (iii) utility scale installations with medium/large/very large field(s) of units.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] FIG. 1A shows a side view of a preferred air-cooled embodiment of the inflatable concentrating photovoltaic module invention.
[0006] FIG. 1B shows an end view of the embodiment of FIG. 1A .
[0007] FIG. 1C shows an end view of the embodiment of FIGS. 1B and 1A , in an inverted stow configuration.
[0008] FIG. 2A shows a side view of a preferred thermosiphon (also spelled thermosyphon) cooled embodiment of the inflatable concentrating photovoltaic module invention.
[0009] FIG. 2B shows an end view of the embodiment of FIG. 2A .
[0010] FIG. 3 shows a side view of a preferred embodiment similar to the embodiment of FIG. 2A , but also fitted with a pump.
[0011] FIG. 4A shows a side view of an alternate embodiment similar to the embodiment of FIG. 1A .
[0012] FIG. 4B shows a side view of another alternate embodiment similar to the embodiment of FIG. 1A .
[0013] FIGS. 5A through 5F show side views of liquid-cooled embodiments of the invention with liquid transport pipes exiting the solar photovoltaic module.
[0014] FIGS. 6A and 6B show side views of combinations of plural solar modules of different types in sequence.
[0015] FIG. 7 shows a side view of an embodiment of the invention that has a solar module with a liquid cooling system.
[0016] FIGS. 8A and 8B show plan views of embodiments with connected arrays of plural inflatable linear heliostatic concentrating solar modules.
[0017] FIGS. 9A through 9H show side views of alternate embodiments of the invention.
[0018] FIGS. 10A through 10J show partial cross-sectional views of alternate embodiments of an inflatable linear heliostatic concentrating solar module, illustrated as a solar photovoltaic module, without limitation.
[0019] FIGS. 11A through 11D show partial side views of the right end structure portion of the left and right end structures.
[0020] FIGS. 12 and 13 show partial side views of deployed and shipping configurations of an upper module portion of an inflatable linear heliostatic concentrating solar module that is a solar photovoltaic module.
[0021] FIGS. 14 and 15 show partial side views of deployed and shipping configurations of a reflector module portion of an inflatable linear heliostatic concentrating solar module that is a solar photovoltaic module, similar to that shown and described in detail earlier in the context of FIG. 1A .
[0022] FIGS. 16A and 16B show partial side views of deployed and shipping configurations of a lower module of an inflatable linear heliostatic concentrating solar module that is a solar photovoltaic module, similar to that shown and described in detail earlier in the context of FIG. 1A .
[0023] FIG. 17 and FIG. 18 show side sectional views of 40 foot and 20 foot representative scale solar modules, disassembled and packed into a representative shipping container.
[0024] FIG. 19 shows a partial end view of an embodiment similar to the embodiment of FIG. 1B .
[0025] FIG. 20 shows a plan view of a floating embodiment with a connected array of plural inflatable linear heliostatic concentrating solar modules, with two axis heliostatic tracking
[0026] FIG. 21 shows a plan view of a floating embodiment with a connected array of plural inflatable linear heliostatic concentrating solar modules, with one axis heliostatic tracking
[0027] FIGS. 22A through 22G show plan views of various floating embodiments of the invention.
[0028] FIGS. 23A through 23D show partial sectional views of various floating embodiments of the invention.
DETAILED DESCRIPTION
[0029] FIG. 1A shows a tilted side view of a preferred air-cooled embodiment of the inflatable concentrating photovoltaic module invention.
[0030] FIG. 1A shows a tilted inflatable linear cooled heliostatic concentrating solar photovoltaic module 1 , comprising: an elongated solar photovoltaic receiver 2 including a portion of substantially linear geometry 3 with a linear axis 4 in its installed orientation being tilted up from a horizontal plane 5 that is perpendicular to the local gravity vector 6 ; a reflection and concentration surface 7 for reflecting and concentrating sunrays 8 ; an elongated upper inflatable volume 9 above said reflection and concentrating surface 7 , with a substantially transparent surface 11 above said upper inflatable volume 9 ; an elongated lower inflatable volume 12 below said reflection and concentrating surface 7 , with a bottom surface 13 below said lower inflated volume 12 ; support structure 15 for supporting said solar photovoltaic module 1 on a supporting surface 16 ; heliostatic control means 18 for aiming a rotatable portion 19 of said solar photovoltaic module 1 as a function of at least one of time and other parameters, such that incoming sunrays 8 from a sunward direction 8 D will be reflected and concentrated by said reflection and concentration surface 7 , onto said elongated solar photovoltaic receiver 2 at a concentration ratio of at least two suns; electrical power means 20 for collecting and transmitting electrical power from said elongated solar photovoltaic receiver 2 ; and cooling means 21 for removing excess heat 27 from said elongated solar photovoltaic receiver 2 , said cooling means 21 including a tilted fluid path 23 that is tilted up in an orientation 24 including a component along said linear axis 4 , wherein buoyancy force acting on heated cooling fluid 26 that is heated by heat 27 from said elongated photovoltaic receiver 2 , contributes to moving said heated cooling fluid 26 upward in said tilted fluid path 23 .
[0031] In the illustrated embodiment the linear axis 4 is tilted from the horizontal plane 5 by a value corresponding substantially to the latitude of the installation of the solar photovoltaic module 1 , such that incoming sunrays would be substantially perpendicular or normal to the linear axis 4 at the time of the vernal and autumnal equinoxes, and tilted at the time of the summer and winter solstices. The illustrated angle of the incoming sunrays 8 coming from a sunward direction 8 D, corresponds approximately to winter solstice at solar noon, when the Sun's effective location will be lower or Southward towards the horizon for Northern Hemisphere installations, and lower or Northward towards the horizon in the Southern Hemisphere installations. Note that the sunrays 8 penetrate through the substantially transparent upper surface 11 , get reflected by the reflection and concentration surface 7 and then go through the transparent upper surface 11 again, before impinging on an elongated linear capture area on the typically downward facing solar cells of the elongated photovoltaic receiver 2 . The sunrays reflected by the reflecting and concentration surface 7 converge towards a focal line of reflected sunrays 8 F and diverge after passing this focal line of reflected sunrays 8 F. It should be noted that a true focal line exists when the reflective surface is a true parabola in shape, but for typical approximate circular section reflectors we define the focal line of reflected sunrays 8 F as the centerline in the middle of the narrowest width part of the reflected beams of sunlight that occurs between where the reflected beams converge and diverge. The location of the focal line of reflected sunrays 8 F is just very slightly below the crown (top) line of the transparent upper surface 11 in the illustrated embodiment in FIG. 1A , and will be seen with greater clarity in FIG. 1B following. The transparent upper surface 11 will preferably utilize a transparent material system that has very high transmissivity, is durable and tough, does not deteriorate when exposed to light and temperature variations and weather elements, and has a “self cleaning” attribute when naturally washed with rainwater. An example material that meets these attributes is ETFE, also known as Tefzel or Fluon, that has already found application in demanding applications in buildings, greenhouses, etc. The reflection and concentration surface should be highly reflective, light weight and low cost, and a reflectorized membrane such as mirror aluminized mylar could be used. The bottom surface 13 should be low cost, rugged and tough and hard to puncture, and suitable for protecting the solar module from hail or damage from storm induced falling twigs etc, when the device is in an inverted storm stow mode. Some examples, without limitation, are (i) a bottom surface material such as thick gage reinforced polyethylene membrane such as the material used in pond liners, and (ii) bubble wrap sandwich plus an external strong skin for the lower surface of the bottom surface 13 .
[0032] FIG. 1A also shows a tilted inflatable linear cooled heliostatic concentrating solar photovoltaic module 1 , comprising: an elongated solar photovoltaic receiver 2 including a portion of substantially linear geometry 3 with a linear axis 4 in its installed orientation being tilted up from a horizontal plane 5 that is perpendicular to the local gravity vector 6 ; a reflection and concentration surface 7 for reflecting and concentrating sunrays 8 ; a substantially enclosed elongated inflatable volume 10 comprising (i) an upper inflatable volume 10 U above said reflection and concentrating surface 7 , with a substantially transparent surface 11 above said upper inflatable volume 10 U, and further comprising (ii) a lower volume 14 below said reflection and concentrating surface 7 , with a bottom surface 13 below said lower volume 14 ; support structure 15 for supporting said solar photovoltaic module 1 on a supporting surface 16 with said linear axis 4 in its installed orientation being tilted up from a horizontal plane 5 that is perpendicular to the local gravity vector 6 ; heliostatic control means 18 for aiming a rotatable portion 19 of said solar photovoltaic module 1 as a function of at least one of time and other parameters, such that incoming sunrays 8 from a sunward direction 8 D will be reflected and concentrated by said reflection and concentration surface 7 , onto said elongated solar photovoltaic receiver 2 at a concentration ratio of at least two suns; electrical power means 20 for collecting and transmitting electrical power from said elongated solar photovoltaic receiver 2 ; and cooling means 21 for removing excess heat 27 from said elongated solar photovoltaic receiver 2 , said cooling means 21 including a tilted fluid path 23 that is tilted up in an orientation 24 including a component along said linear axis 4 , wherein buoyancy force acting on heated cooling fluid 26 that is heated by heat 27 from said elongated photovoltaic receiver 2 , contributes to moving said heated cooling fluid 26 upward in said tilted fluid path 23 .
[0033] In the embodiment of FIG. 1A the fan 28 blows cool ambient air up a air cooling pipe 22 A, which is preferably made of heat conductive material such as aluminum or copper alloys, to cite a couple of examples without limitation. The air cooling pipe 22 A conducts excess heat 27 from the elongated solar photovoltaic receiver 2 to a stream of air flowing up the air cooling pipe 22 A, to the right in FIG. 1A . The air serves as the heated cooling fluid 26 in this embodiment, and is driven in part to the right in FIG. 1A (upward and Northward in a typical Northern Hemisphere installation, upward and Southward in a typical Southern Hemisphere installation) by the natural buoyancy force that acts on heated fluid, and driven in part by the fan 28 . The heated air exits the air cooling pipe 22 A through an exhaust hood 22 E that serves as heat transfer means 32 , for venting the hot air which is the heated cooling fluid 26 , out into the cool atmosphere which is the cooler environment 34 . The illustrated exhaust hood 22 E has a roof element to prevent rain or other precipitation from falling into the air cooling pipe 22 A. The exhaust orifice of the exhaust hood 22 E and the intake orifice to the fan 28 may optionally covered with grille, mesh or screen material that allows mostly free flow of air, but prevents birds or insects or debris from entering into the air cooling pipe 22 A. While a blowing fan located near the bottom of the air cooling pipe is shown in the illustrated embodiment, it will be understood that alternate fan locations in the cooling pipe, or a sucking fan located near the top of the air cooling pipe, could be employed alternatively or in combination in other embodiments of the invention as claimed.
[0034] FIG. 1A also illustrates a solar photovoltaic module 1 , wherein the elongated solar photovoltaic receiver 2 includes at least one of (i) a single row 35 S of solar cells 36 (shown), (ii) a double row of solar cells (not shown), and (iii) multiple substantially linear rows of solar cells (not shown); which solar cells 36 are connected together by wires 38 at least in one of in series, in parallel, and in a combination of series and parallel; and which solar cells 36 are attached to a substantially linear upper beam structure 40 that serves as conductive heat transfer means 41 for enabling conductive heat transfer from said solar cells 36 to said heated cooling fluid 26 , which heated cooling fluid 26 is heated by heat from said elongated photovoltaic receiver 2 when the Sun 8 S is shining and said solar photovoltaic module 1 is operating.
[0035] The upper beam structure 40 may incorporate heat sink extrusion members in its interior to facilitate cooling performance, and in a version with two sided solar cells at the bottom of the upper beam structure 40 , the top of the upper beam structure 40 may be made of transparent material. Solar cells 36 may be monocrystalline or polycrystalline, or special high temp CPV cells known in the art; may have leads/connections in the back only or back and front; may have antireflective coatings and/or a protective film cover; may use encapsulant and/or side seals; and may have highly conductive wire side leads.
[0036] FIG. 1A also illustrates a solar photovoltaic module 1 , wherein the heated cooling fluid 26 comprises heated cooling air 26 A and wherein a fan 28 further contributes to moving said heated cooling fluid 26 upward in said tilted fluid path 23 ; said cooling means 21 further including heat transfer means 32 for transferring heat from said heated cooling fluid 26 to a cooler environment 34 outside said solar photovoltaic module 1 , which heat transfer means 32 includes at least one of (i) a cooling tube 82 with internal air flow 82 I at least partially driven by said fan 28 , (ii) cooling fins 83 , (iii) a cooling plate 83 P (not shown), (iii) cooling spikes 83 S (not shown), (iv) a cooling extrusion 83 E (here the same as the cooling fins 83 ) and (v) a cooling radiator 83 R (not shown).
[0037] FIG. 1A also illustrates a solar photovoltaic module 1 , wherein the solar photovoltaic module 1 includes a central portion 44 with an approximately constant cross-section on planar cuts perpendicular to the axis of elongation of said elongated solar photovoltaic receiver 2 , and further includes left and right end structures 45 attached at least one of (a) hingedly and (b) fixedly, near the left and right ends of said upper beam structure 40 , which left and right end structures 45 each comprise at least one of (i) a beam member 46 B (shown), (ii) a wheel member 46 W (shown), (iii) a rim member 46 R (shown), (iv) plural spoke members 46 S (shown), (v) a hub member 46 H (shown), (vi) an axle member 46 A (shown), (vii) a plate member 46 P (not shown), (viii) a dished plate member 46 D (not shown) and (ix) a second beam member 46 SB (not shown) substantially perpendicular to said beam member 46 B.
[0038] The left and right end structures 45 provide end containment for at least one of normal and non-normal conditions, for the left and right ends of the reflection and concentrating surface 7 as well as for the left and right ends of the upper inflatable volume 9 and lower inflatable volume 12 .
[0039] The embodiment illustrated in FIG. 1A also shows a solar photovoltaic module 1 , wherein the elongated upper inflatable volume 9 includes an inflatable central portion 47 with an approximately constant cross-section on planar cuts perpendicular to the axis of elongation of said elongated upper inflatable volume 9 , and further includes left and right end closure portions 48 on the left and right sides of said inflatable central portion 47 , which left and right closure portions 48 serve to provide left and right side enclosure for said elongated upper inflatable volume 9 , wherein said left and right end closure portions 48 are at least one of (a) transparent, (b) partially transparent, (c) reflective, (d) partially reflective or reflective on the inner side only, and (e) nontransparent; and wherein said left and right end closure portions 48 comprise at least one of (i) a membrane 48 M, (ii) an at least partially framed membrane 48 F (shown), (iii) an at least partially rigid dome segment 48 R (not shown), (iv) a plate member 48 P (not shown), and (v) a dished plate member 48 D (not shown).
[0040] The left and right end closure portions 48 may optionally use single or double wall ETFE or polycarbonate or other transparent material. Optional end members that close the right and left ends of the lower inflatable volume 12 may be nontransparent, and may use the same material or sheeting that is used for the bottom surface 13 .
[0041] FIG. 1A also shows a solar photovoltaic module 1 , wherein the reflection and concentration surface 7 includes a frame 7 F with perimeter structural members 50 P supporting said reflection and concentration surface 7 along at least portions of the perimeter of said reflection and concentration surface 7 ; and further comprising structural connection means 43 for at least one of detachably and permanently structurally connecting said frame 7 F to said left and right end structures 45 .
[0042] The embodiment illustrated in FIG. 1A further illustrates a solar photovoltaic module 1 , wherein the reflection and concentration surface 7 includes at least one of (i) a reflective membrane 7 R which is reflective on its upper side and wherein an upwardly concave desired shape 7 S (not visible in this view) of said reflective membrane 7 R is at least in part maintained by the application of differential inflation pressure between said upper inflatable volume 9 and said lower inflatable volume 12 , (ii) a mirror element 7 M (not shown) which is reflective and concave on its upper side 7 U, and (iii) a frame supported reflective membrane 7 FR which is supported by a frame 7 F and is reflective and concave on its upper side 7 U, wherein said frame 7 F comprises at least one of (a) perimeter structural members 50 P supporting said reflection and concentration surface 7 along at least portions of the perimeter of said reflection and concentration surface 7 , which perimeter structural members 50 P also contribute to perimeter restraint of at least one of said substantially transparent surface 11 and said bottom surface 13 ; (b) shaping means 50 S adjacent to said reflection and concentration surface 7 serving as shaping means for contributing to an upwardly concave desired shape 7 S of said reflection and concentration surface 7 ; and (c) frame supported damping means 50 FD adjacent to said reflection and concentration surface 7 serving as damping means 50 D for damping undesirable motion of said reflection and concentration surface 7 .
[0043] Note that the word “upwardly” refers to a direction with a sunward vector component, and typically best aligned with the direction vector to the Sun at solar noon. Note that the adjacent shaping means 50 S may comprise at least one of connected substantially rigid shaping structure and connected shaping tension elements, and that the damping means 50 FD may include viscoelastic damping materials or layer(s). Note also that undesirable motion may be induced by wind loads, by motor driven heliostatic pointing, by structural oscillations or vibrations, and by other causes.
[0044] The embodiment illustrated in FIG. 1A also illustrates a solar photovoltaic module 1 , further comprising rotatable attachment means 52 for at least one of detachably and permanently rotatably attaching said left and right end structures 45 to said support structure 15 for supporting said solar photovoltaic module 1 , wherein said rotatable attachment means 52 includes at least one of (i) a hub 53 H, (ii) an axle 53 A, (iii) a shaft 53 S, (iv) a bearing 53 B, (v) a pillow-block bearing 53 PB (not shown), and (vi) a joint 53 J (not shown); and wherein said heliostatic control means 18 for aiming a rotatable portion 19 of said solar photovoltaic module 1 includes powered means 55 for controllably rotating at least one of said left and right end structures 45 , relative to said support structure 15 for supporting said solar photovoltaic module 1 on a supporting surface 16 .
[0045] The illustrated powered means 55 provides means for controllably rotating the left end structure 45 and uses a motor driving a belt via a pulley, as illustrated. Different belt types such as timing belts, toothed belts or belt analogues such as chains can alternatively be used. The belt engages and drives the rim member 46 R of a wheel member 46 W in the illustrated embodiment of the invention, with a substantial gear reduction inherent in the belt drive as the wheel rim has a much larger diameter than the diameter of the pulley. This gear reduction is over and above any gear reduction built into the motor, which may for instance be a gearmotor (illustrated) or a stepper motor (an alternative).
[0046] Thus a solar photovoltaic module 1 is shown, wherein the heliostatic control means 18 for aiming a rotatable portion 19 of said solar photovoltaic module 1 as a function of at least one of time and other parameters, includes powered elevation control means 56 for orienting said rotatable portion 19 of said solar photovoltaic module 1 over varying elevation angle 60 (see view in FIG. 1B ) to follow the apparent daily motion of the Sun 8 S from East to West, wherein said powered elevation control means 56 comprises at least one of (a) a motor 61 M, (b) a gear motor 61 G, (c) a stepper motor 61 S (not shown), and (d) an actuator 61 A (not shown); and wherein said powered elevation control means 56 further comprises control linking means 62 serving as controllable means for variable-geometry linking between said support structure 15 on the first hand, and said rotatable portion 19 of said solar photovoltaic module 1 on the second hand; said control linking means 62 comprising at least one of (i) a powered pulley 63 P engaging and driving an elevation control revolving drive element 63 E selected from the group consisting of a belt 63 B and a chain 63 H (not shown) and a cable 63 C (not shown), (ii) a powered sprocket 63 S (not shown) engaging and driving an elevation control revolving drive element 63 E selected from the group consisting of a chain 63 H (not shown) and a toothed belt 63 TB (not shown) and a belt with periodic holes 63 BP (not shown) and a toothed cable 63 TC (not shown), (iii) a powered gear element 63 PG (not shown) engaging and driving a driven gear element 63 DG (not shown), and (iv) an orientation drive linkage 63 OD (not shown).
[0047] The embodiment illustrated in FIG. 1A also illustrates a solar photovoltaic module 1 , further comprising ballast means 57 located at a lower end region 45 E of at least one of said left end and right end structures 45 , for acting at least in part as a counterbalancing weight to the weight of said upper beam structure 40 , which ballast means 57 comprises at least one of (a) a ballast weight 58 W (not shown) located at the lower end region 45 E of left end structure 45 L, (b) a ballast weight 58 W (not shown) located at the lower end region 45 E of right end structure 45 R, (c) a ballast beam 58 B that connects the lower end regions 45 E of said left end structure 45 L and said right end structure 45 R, through at least one of detachable and permanent connection means, and (d) a fillable hollow ballast beam 58 F that connects the lower end regions 45 E of said left end structure 45 L and said right end structure 45 R, through at least one of detachable and permanent connection means.
[0048] FIG. 1A also shows a solar photovoltaic module 1 , wherein the support structure 15 for supporting said solar photovoltaic module 1 on a supporting surface 16 comprises a base frame 72 including at least one of (i) tubular frame elements 73 TU, (ii) beam elements 73 B, (iii) a plate element 73 P (not shown), (iv) a truss element 73 TR, (v) a frame tilting structure 74 , (vi) a variable height adjustable frame tilting structure 74 V, (vii) a controllable height frame tilting structure 74 C and (viii) at least one of a motorized and an actuated controllable height frame tilting structure 74 MAC (not shown); wherein said supporting surface 16 comprises at least one of (a) a ground surface 16 G (optional but not specifically called out in this Figure), (b) a paved surface 16 P (optional but not specifically called out in this Figure), (c) a floor surface 16 F (optional but not specifically called out in this Figure), (d) a roof surface 16 R (optional but not specifically called out in this Figure), and (e) a water surface 16 W (not shown) comprising at least one of (i) a frozen water surface and (ii) a liquid water surface on which said solar photovoltaic module 1 is supported at least in part by a buoyancy force 16 B (not shown).
[0049] Note that a variable height adjustable frame tilting structure 74 V, a controllable height frame tilting structure 74 C, or a motorized or actuated controllable height frame tilting structure 74 MAC, could be beneficially used to increase harvestable solar energy at seasons away from the vernal and autumnal equinoxes, when the Sun's apparent elevation angle can change by over 20 degrees from the nominal latitude tilt of the axis of rotation of the typical tilt frame structure with a North-South axis. The variable height adjustable frame tilting structure 74 V may have fixed stops corresponding to discrete times, e.g. one position per month.
[0050] The legs of the frame tilting structure 74 may either stand on the supporting surface 16 optionally using some kind of nonskid leg cap or footing, or may be positively anchored to or in the supporting surface 16 .
[0051] FIG. 1B shows a partial end view of the embodiment of FIG. 1A from the left end at approximately double the scale of FIG. 1A , and more clearly illustrates some of the features of the invention of FIG. 1A that can be better understood through the addition of this end view to supplement the side view of FIG. 1A . Examples of more clearly illustrated features include (i) the elevation angle 60 and (ii) the sunrays reflected by the reflecting and concentration surface 7 converging towards a focal line of reflected sunrays 8 F and diverging after passing upward past this focal line of reflected sunrays 8 F.
[0052] A few additional features are visible in the view of FIG. 1B , including: (i) a motor 61 M driving a powered pulley 63 P that in turn drives a drive belt 63 B that rotates the rotatable portion 19 of the solar photovoltaic module 1 to perform heliostatic one-axis tracking; (ii) belt tensioning means 63 BT for keeping the drive belt 63 B for heliostatic control at an appropriate tension; (iii) the wheel member 46 W with a hub member 46 H engaging an axle member 46 A, spoke members 46 S connecting the hub member 46 H with a rim member 46 R that is ringed around its perimeter by a rim member 46 R that is driven by the drive belt 63 B; (iv) cooling means 21 using a fan 28 blowing cooling air into an air cooling pipe 22 A that serves as a cooling tube 82 , fitted with the illustrated cooling fins 83 here comprising cooling extrusions 83 E; (v) an upper inflatable volume 10 U above an upwardly concave reflection and concentrating surface 7 that is supported and shaped by perimeter structural members 50 P and shaping means 50 S, with a substantially transparent surface 11 above the upper inflatable volume 10 U; and (vi) a lower inflatable volume 10 L below the upwardly concave reflection and concentrating surface 7 , with a bottom surface 13 below the lower inflated volume 10 L.
[0053] FIG. 1C shows an end view of the embodiment of FIGS. 1B and 1A , in an inverted stow configuration. FIG. 1C shows a solar photovoltaic module 1 , wherein the heliostatic control means 18 for aiming a rotatable portion 19 of said solar photovoltaic module 1 as a function of at least one of time and other parameters, further includes inverted stow means 70 IS for stowing said rotatable portion 19 of said solar photovoltaic module 1 in an at least partially inverted configuration 70 PI, when commanded by at least one of (i) a user command 70 UC, (ii) a protective stow command 69 SC algorithmically computed from at least one signal 64 from a sensor 65 indicating a potentially hazardous environmental condition, and (iii) a protective stow command 69 SC algorithmically computed from at least one signal 64 from a sensor 65 indicating a failure condition.
[0054] As an example, inverted stow can be beneficially used in a hailstorm where hail may fall on the solar photovoltaic module 1 , or wind storm where blowing debris may fall on the solar photovoltaic module 1 . Other threats for which inverted stow may be warranted include heavy rain, snow, sleet, a sandstorm, heavy bird droppings, and falling debris such as twigs and windfalls from trees. With inverted stow, the potentially damaging falling items would hit a puncture-resistant, tough/rugged and potentially multi-layer bottom surface 13 cushioned by the lower inflatable volume 10 L, rather than the substantially transparent surface 11 bounding the upper inflatable volume 10 U. In some conditions such as a sandstorm where an environmental threat is from the side rather than the top of the solar photovoltaic module 1 , a sideward stow position could be commanded based on sensed/computed threat, with the bottom surface 13 facing the threat direction. Examples of a sensor 65 indicating a potentially hazardous environmental condition could include sensors for wind, precipitation, hail, impact, and load.
[0055] FIG. 2A shows a side view of a preferred thermosiphon cooled embodiment of the inflatable concentrating photovoltaic module invention, that is similar to the embodiment of FIG. 1A but with the air cooling system replaced by a liquid cooling system.
[0056] FIG. 2A illustrates a solar photovoltaic module 1 , wherein the heated cooling fluid 26 comprises at least one of heated cooling water 84 W [option not shown] and heated liquid coolant 84 C [shown]; wherein at least one of a pump 30 [not shown] and a thermosiphon 31 [shown] contributes to moving said heated cooling fluid 26 upward in said tilted fluid path 23 ; and further comprising at least one of: (a) heat transfer means 32 [shown] for transferring heat from said heated cooling fluid 26 to a cooler environment 34 outside said solar photovoltaic module 1 ; and
[0000] (b) beneficial heat use means 77 for beneficially using heat from said heated cooling fluid 26 [not shown].
[c19 but without beneficial heat specifications]
[0057] The illustrated thermosiphon 31 includes liquid heating tube means 31 H here comprising a shallow depth enclosed near-rectangular tubular flow path immediately above and adjacent to the back sides of the solar cells in the elongated photovoltaic receiver 2 , in which the heated cooling fluid 26 heated by heat 27 from said elongated photovoltaic receiver 2 rises due to buoyancy forces that naturally act on heated liquids. At the upper end (right end in this Figure) of the tubular flow path, the enclosed closed-loop flow path curves upward and back into a radiator 31 R here comprising a cooling radiator 83 R in the form of a spiral radiator. An upper tank for the heated cooling fluid 26 may optionally be provided but is not shown, in a manner as known from the art of thermosiphon systems. In the illustrated embodiment, the heated liquid spirals downward through the radiator 31 R whilst cooling and transferring heat by heat transfer means 32 (through the walls of the spiral radiator) for transferring heat from the heated cooling fluid 26 to a cooler environment 34 (the atmosphere) outside the solar photovoltaic module 1 . The cooled fluid then loops down and around to the lower end (left end in the Figure) inflow connection into the liquid heating tube means 31 H. Note that the illustrated thermosiphon system requires no external power and has no pump, but that alternate embodiments may utilize a supplementary pump.
[0058] FIG. 2A shows a tilted inflatable linear cooled heliostatic concentrating solar photovoltaic module 1 , comprising: an elongated solar photovoltaic receiver 2 including a portion of substantially linear geometry 3 with a linear axis 4 in its installed orientation being tilted up from a horizontal plane 5 that is perpendicular to the local gravity vector 6 ; a reflection and concentration surface 7 for reflecting and concentrating sunrays 8 ; an elongated upper inflatable volume 9 above said reflection and concentrating surface 7 , with a substantially transparent surface 11 above said upper inflatable volume 9 ; an elongated lower inflatable volume 12 below said reflection and concentrating surface 7 , with a bottom surface 13 below said lower inflated volume 12 ; support structure 15 for supporting said solar photovoltaic module 1 on a supporting surface 16 ; heliostatic control means 18 for aiming a rotatable portion 19 of said solar photovoltaic module 1 as a function of at least one of time and other parameters, such that incoming sunrays 8 from a sunward direction 8 D will be reflected and concentrated by said reflection and concentration surface 7 , onto said elongated solar photovoltaic receiver 2 at a concentration ratio of at least two suns; electrical power means 20 for collecting and transmitting electrical power from said elongated solar photovoltaic receiver 2 ; and cooling means 21 for removing excess heat 27 from said elongated solar photovoltaic receiver 2 , said cooling means 21 including a tilted fluid path 23 that is tilted up in an orientation 24 including a component along said linear axis 4 , wherein buoyancy force acting on heated cooling fluid 26 that is heated by heat 27 from said elongated photovoltaic receiver 2 , contributes to moving said heated cooling fluid 26 upward in said tilted fluid path 23 .
[0059] FIG. 2A also shows a tilted inflatable linear cooled heliostatic concentrating solar photovoltaic module 1 , comprising: an elongated solar photovoltaic receiver 2 including a portion of substantially linear geometry 3 with a linear axis 4 in its installed orientation being tilted up from a horizontal plane 5 that is perpendicular to the local gravity vector 6 ; a reflection and concentration surface 7 for reflecting and concentrating sunrays 8 ; a substantially enclosed elongated inflatable volume 10 comprising (i) an upper inflatable volume 10 U above said reflection and concentrating surface 7 , with a substantially transparent surface 11 above said upper inflatable volume 10 U, and further comprising (ii) a lower volume 14 below said reflection and concentrating surface 7 , with a bottom surface 13 below said lower volume 14 ; support structure 15 for supporting said solar photovoltaic module 1 on a supporting surface 16 with said linear axis 4 in its installed orientation being tilted up from a horizontal plane 5 that is perpendicular to the local gravity vector 6 ; heliostatic control means 18 for aiming a rotatable portion 19 of said solar photovoltaic module 1 as a function of at least one of time and other parameters, such that incoming sunrays 8 from a sunward direction 8 D will be reflected and concentrated by said reflection and concentration surface 7 , onto said elongated solar photovoltaic receiver 2 at a concentration ratio of at least two suns; electrical power means 20 for collecting and transmitting electrical power from said elongated solar photovoltaic receiver 2 ; and cooling means 21 for removing excess heat 27 from said elongated solar photovoltaic receiver 2 , said cooling means 21 including a tilted fluid path 23 that is tilted up in an orientation 24 including a component along said linear axis 4 , wherein buoyancy force acting on heated cooling fluid 26 that is heated by heat 27 from said elongated photovoltaic receiver 2 , contributes to moving said heated cooling fluid 26 upward in said tilted fluid path 23 .
[0060] FIG. 2A also illustrates a solar photovoltaic module 1 , wherein the elongated solar photovoltaic receiver 2 includes at least one of (i) a single row of solar cells (not shown), (ii) a double row 35 D of solar cells 36 (shown), and (iii) multiple substantially linear rows of solar cells (not shown); which solar cells 36 are connected together by wires 38 at least in one of in series, in parallel, and in a combination of series and parallel; and which solar cells 36 are attached to a substantially linear upper beam structure 40 that serves as conductive heat transfer means 41 for enabling conductive heat transfer from said solar cells 36 to said heated cooling fluid 26 , which heated cooling fluid 26 is heated by heat from said elongated photovoltaic receiver 2 when the Sun 8 S is shining and said solar photovoltaic module 1 is operating.
[0061] The substantially linear upper beam structure 40 here also doubles as the previously described liquid heating tube means 31 H here comprising a shallow depth enclosed near-rectangular tubular flow path immediately above and adjacent to the back sides of the solar cells in the elongated photovoltaic receiver 2 .
[0062] The illustrated powered means 55 provides means for controllably rotating the left end structure 45 and uses a motor-driven powered sprocket 63 S engaging and driving an elevation control revolving drive element 63 E consisting of a toothed belt 63 TB, as illustrated. Different belt types including timing belts, toothed belts or belt analogues such as chains can alternatively be used. The toothed belt 63 TB engages and drives a tooth-engaging rim member 46 R of a wheel member 46 W in the illustrated embodiment of the invention, with a substantial gear reduction inherent in the belt drive as the wheel rim has a much larger diameter than the diameter of the pulley. This gear reduction is over and above any gear reduction built into the motor, which may for instance be a stepper motor 61 S (illustrated) or a gearmotor (an alternative).
[0063] Thus a solar photovoltaic module 1 is shown in FIG. 2A , wherein the heliostatic control means 18 for aiming a rotatable portion 19 of said solar photovoltaic module 1 as a function of at least one of time and other parameters, includes powered elevation control means 56 for orienting said rotatable portion 19 of said solar photovoltaic module 1 over varying elevation angle 60 (see view in FIG. 2B ) to follow the apparent daily motion of the Sun 8 S from East to West, wherein said powered elevation control means 56 comprises at least one of (a) a motor 61 M, (b) a gear motor 61 G (not shown), (c) a stepper motor 61 S (shown), and (d) an actuator 61 A (not shown); and wherein said powered elevation control means 56 further comprises control linking means 62 serving as controllable means for variable-geometry linking between said support structure 15 on the first hand, and said rotatable portion 19 of said solar photovoltaic module 1 on the second hand; said control linking means 62 comprising at least one of (i) a powered pulley 63 P (not shown) engaging and driving an elevation control revolving drive element 63 E selected from the group consisting of a belt 63 B and a chain 63 H and a cable 63 C, (ii) a powered sprocket 63 S (shown) engaging and driving an elevation control revolving drive element 63 E (shown) selected from the group consisting of a chain 63 H (not shown) and a toothed belt 63 TB (shown) and a belt with periodic holes 63 BP (not shown) and a toothed cable 63 TC (not shown), (iii) a powered gear element 63 PG (not shown) engaging and driving a driven gear element 63 DG, and (iv) an orientation drive linkage 63 OD (not shown).
[0064] Finally, FIG. 2A also shows the solar photovoltaic module 1 , wherein the heliostatic control means 18 for aiming a rotatable portion 19 of said solar photovoltaic module 1 as a function of at least one of time and other parameters, performs its aiming function as a function of at least one of (i) a signal 64 (shown) from a Sun angle sensor 65 S (shown), (ii) time of day from a clock 66 C, (iii) time of year from a clock 66 C, (iv) year from a clock 66 C, (v) latitude data 66 LA of the location of installation 66 LI of said solar photovoltaic module 1 , (vi) longitude data 66 L 0 of the location of installation 66 LI of said solar photovoltaic module 1 , (vii) true heading orientation 66 TH of said support structure 15 relative to said supporting surface 16 , and (viii) slope 16 SL of said supporting surface 16 .
[0065] The Sun angle sensor 65 S sends signals to the powered elevation control means 56 to rotate the solar reflector and receiver subsystems to track the Sun's apparent motion through the skies. During periods of darkness such as night or cloud cover, the rotation will stop, and resume when the Sun is again visible. Therefore at dawn, the device will rotate back from facing West to facing East to face the rising Sun. For adverse weather conditions necessitating an downward facing emergency stow orientation, an emergency stow command will override the pointing command from the Sun angle sensor 65 S.
[0066] FIG. 2B shows an end view of the embodiment of FIG. 2A , that is also similar to the embodiment of FIG. 1B but with the air cooling system replaced by a liquid cooling system.
[0067] FIG. 2B shows a partial end view of the embodiment of FIG. 2A from the left end at approximately double the scale of FIG. 2A , and more clearly illustrates some of the features (e.g., elevation angle 60 ) of the invention of FIG. 2A that can be better understood through the addition of this end view to supplement the side view of FIG. 2A .
[0068] A few additional features are visible in the view of FIG. 2B , including: (i) a motor 61 M (here a stepper motor 61 S) driving a powered sprocket 63 S that in turn drives a toothed belt 63 TB that rotates the rotatable portion 19 of the solar photovoltaic module 1 to perform heliostatic one-axis tracking; (ii) belt tensioning means 63 BT for keeping the toothed belt 63 TB for heliostatic control at an appropriate tension; (iii) the wheel member 46 W with a hub member 46 H engaging an axle member 46 A, spoke members 46 S connecting the hub member 46 H with a rim member 46 R that is ringed around its perimeter by a rim member 46 R that is driven by the toothed belt 63 TB; (iv) a substantially linear upper beam structure 40 that also doubles as the previously described liquid heating tube means 31 H comprising a shallow depth enclosed near-rectangular tubular flow path immediately above and adjacent to the back sides of the solar cells in the elongated photovoltaic receiver 2 , and thus serves as an integral part of the cooling means 21 using heated cooling fluid 26 comprising heated liquid coolant 84 C that flows in a thermosiphon 31 , and further comprising heat transfer means 32 including a radiator 31 R comprising a cooling radiator 83 R in the form of a spiral radiator for transferring heat from said heated cooling fluid 26 to a cooler environment 34 ; (v) an upper inflatable volume 10 U above an upwardly concave reflection and concentrating surface 7 that is supported and shaped by perimeter structural members 50 P and shaping means 50 S, with a substantially transparent surface 11 above the upper inflatable volume 10 U; and (vi) a lower inflatable volume 10 L below the upwardly concave reflection and concentrating surface 7 , with a bottom surface 13 below the lower inflated volume 10 L.
[0069] FIG. 3 shows a side view of a preferred embodiment of a solar photovoltaic module 1 similar to the embodiment of FIG. 2A , but also fitted with a pump 30 . The pump 30 increases or augments the buoyancy induced flow in the liquid cooling system with the thermosiphon 31 . Pump augmented cooling can be provided either all the time when the solar photovoltaic module 1 is operational, or at selected times when augmented cooling is needed such as times of maximum solar radiation and/or maximum ambient temperature and/or when a temperature sensor adjacent to or imbedded in a solar cell indicates a temperature above a threshold value.
[0070] FIG. 3 thus illustrates a solar photovoltaic module 1 , wherein the heated cooling fluid 26 comprises at least one of heated cooling water 84 W [shown] and heated liquid coolant 84 C [option not shown]; wherein at least one of a pump 30 [shown] and a thermosiphon 31 [also shown] contributes to moving said heated cooling fluid 26 upward in said tilted fluid path 23 ; and further comprising at least one of: (a) heat transfer means 32 [shown] for transferring heat from said heated cooling fluid 26 to a cooler environment 34 outside said solar photovoltaic module 1 ; and
[0000] (b) beneficial heat use means 77 for beneficially using heat from said heated cooling fluid 26 [not shown]. PS [c19 but without beneficial heat specifications]
[0071] FIG. 4A shows a side view of an alternate embodiment similar to the embodiment of FIG. 1A , wherein the fan 28 blows cooling air not only directly into the air cooling pipe 22 A, but also into a bypass air pipe 22 B which in the illustrated embodiment is bifurcated into a branch in front and branch behind the air cooling pipe 22 A, as seen in from this side view perspective. The bypass air pipe 22 B in each branch also has a contracting or tapering cross-sectional area going with the flow from left to right, to prevent adverse pressure gradients. The bypass cooling air feeds into the primary air cooling pipe 22 A through air feed holes 22 H on the near and far side walls of the air cooling pipe 22 A, at representative selected locations down the length of the pipe as illustrated. The motivation of providing a bypass air flow path is as follows. The cooling air in the primary air cooling pipe 22 A would normally get hotter and hotter moving from left to right along the pipe as illustrated, as more waste heat from the solar cells gets transferred progressively into the cooling air flow tube. By inserting fresh cool air from the bypass ducts into middle portions of the air cooling pipe 22 A through the air feed holes 22 H and preferably impinging at least in part on the cooling fins 83 , cooling air temperatures and adjacent photovoltaic receiver/solar cell temperatures can be kept from getting very high towards the right or exhaust end of the air cooling pipe 22 A, and in this manner the efficiency loss of the solar cells near the right end of the Figure (due to higher operating temperatures) can be reduced or mitigated.
[0072] Alternate geometries of bypass air paths are of course possible within the spirit and scope of the invention, including separate pipes and internal flow control or guide walls within the air cooling pipe 22 A.
[0073] FIG. 4A also illustrates a solar photovoltaic module 1 , further comprising at least one of (i) user input computer means 68 IC for receiving and executing a user input instruction 68 I, (ii) sensor input computer means 68 SIC for receiving and processing an input signal 64 from a sensor 65 (a Sun angle sensor 65 S in the illustrated embodiment), (iii) aiming computer means 68 AC for algorithmically computing and commanding desired orientation 69 D 0 (reflective mean surface facing sunward) of said rotatable portion 19 of said solar photovoltaic module 1 , (iv) stow computer means 68 SC (not shown) for computing and commanding a protective stow position 69 S (not shown) of said rotatable portion 19 of said solar photovoltaic module 1 , and (v) diagnostic computer means 68 DC for identifying at least one of nonoptimal operation, faulty operation and a failure condition of said solar photovoltaic module 1 .
[0074] Examples of computer means that could be employed include a digital computer, analog computer, hybrid computer, digital processor, microprocessor, computer hardware, computer firmware and computer software.
[0075] FIG. 4A also illustrates a solar photovoltaic module 1 , further comprising means for performing inflation control 75 including at least one of means for increasing inflation pressure 75 I, means for maintaining inflation pressure 75 M, means for decreasing inflation pressure 75 D, means for limiting inflation pressure 75 L (not specifically shown) and means for controllably adjusting inflation pressure 75 C (not specifically shown), in at least one of said upper inflatable volume 9 and said lower inflatable volume 12 , wherein said means for performing inflation control 75 includes at least one of an inflation valve 76 I, a deflation valve 76 D, a pressure limiting valve 76 PL, a pressure relief valve 76 PR (not specifically shown), an adjustable gang valve 76 G (not specifically shown), a differential pressure maintaining device 76 DP (not specifically shown), an openable orifice 76 O (not specifically shown) and an air pump 76 AP (not specifically shown).
[0076] In the illustrated embodiment, separate inflation valves are shown provided for inflating the upper inflatable volume 9 and the lower inflatable volume 12 , with each having features similar to an automobile tire inflation valve to enable inflation, deflation, and flow blocking as desired by a user with an air pump and a deflation prong to engage a valve tip. The inflation valves will preferably incorporate a pressure limiting function and automatically stop inflation beyond optionally different threshold values for the upper inflatable volume 9 and the lower inflatable volume 12 . In normal use the target set pressure in the upper inflatable volume 9 will be set at a value higher than the target set pressure in the lower inflatable volume 12 .
[0077] FIG. 4B shows a side view of another alternate embodiment similar to the embodiments of FIG. 1A and FIG. 4A , but with a forced air cooling system comprising a downward blowing fan 28 that receives air through an inlet hood 22 I, with the air from the downward blowing fan 28 forking into left and right flowing streams of internal air flow 82 I, as shown, that cool the elongated solar photovoltaic receiver 2 and exhaust through left and right exhaust hoods 22 E. The inlet hood 22 I and fan 28 are located partway along the length of the air cooling pipe 22 A, as illustrated. A nominal location below the halfway point of the air cooling pipe is shown, as the left (downward) flowing stream in the view of the Figure has to overcome the opposing buoyancy forces acting on the heated air, while the right (upward) flowing stream is aided by the buoyancy forces acting on the heated air.
[0078] FIGS. 5A through 5F show side views of liquid-cooled embodiments of the invention with liquid transport pipes exiting the solar photovoltaic module 1 .
[0079] FIG. 5A shows an embodiment of the invention in many respects similar to the embodiments of FIG. 1A and FIG. 2A , but with a cooling system now comprising a liquid cooling system with liquid transport pipes 33 into and out of the solar photovoltaic module 1 . Cooler liquid 84 CL is transported by an inflow liquid transport pipe 33 I that originates at a location external to the solar photovoltaic module 1 , which inflow liquid transport pipe 33 I is then is routed through members of the solar photovoltaic module 1 to feed into the bottom end (left end in the view of FIG. 5A ) of the liquid heating tube means 31 H, where the liquid (e.g., a heated liquid coolant 84 C shown) flows upwards (to the right in the view of FIG. 5A ) while absorbing heat from the elongated solar receiver 2 A (that may be one or both of an elongated solar photovoltaic receiver 2 and/or an elongated solar thermal receiver 2 T) and increasing in temperature. The hotter liquid 84 HL, which may also be mixed phase with some boiling occurring in some embodiments, exits the top end (right end in the view of FIG. 5A ) of the liquid heating tube means 31 H into an outflow liquid transport pipe 33 O, which outflow liquid transport pipe 33 O is routed through members of the solar photovoltaic module 1 and subsequently exits to a location external to the solar photovoltaic module 1 . While the cooling liquid flow path is shown on the back side of the downward facing solar cells of the elongated photovoltaic receiver 2 , in alternate embodiments the liquid flow path may be on the front side of the downward facing solar cells with a transparent cooling fluid such as water flowing in a transparent (e.g., glass, polycarbonate, ETFE, etc) flow channel, and/or on the lateral sides of the solar cells, and/or in a combination of geometric locations relative to the solar cells.
[0080] Note that the illustrated inflow liquid transport pipe 33 I and outflow liquid transport pipe 33 O both include fluid flow rotary joints 53 RJ including an axle member 46 A. It should be understood that in alternate embodiments rotary joints, rotary unions or flexible hose fittings can alternatively be used to transport liquid across the rotating interfaces between (a) the nonrotating support structure 15 and (b) the rotatable portion 19 of the solar photovoltaic module 1 that includes the reflection and concentration surface 7 and the elongated solar receiver 2 A.
[0081] The liquid cooling system of FIG. 5A can effectively cool an elongated solar receiver 2 A that is an elongated solar photovoltaic receiver 2 and keep the photovoltaic cells or solar cells on the photovoltaic receiver at a lower temperature where they are not at risk of thermally induced damage and where they operate at higher electric power harvesting efficiency. The liquid cooling system can be either closed-loop or open-loop, and use water or other coolant liquids, as known from the prior art of many variant liquid cooling systems. Furthermore, additional renewable energy can optionally be harvested by utilizing the temperature difference between the hotter liquid 84 HL and the cooler liquid 83 CL to run a thermodynamic cycle engine 78 E (not shown) and/or a thermoelectric device 81 D (not shown), to produce mechanical and/or electrical output. In the case of this option, the elongated solar receiver 2 A serves as both an elongated solar photovoltaic receiver 2 and an elongated solar thermal receiver 2 T concurrently. In a still further variant embodiment, a photovoltaic receiver 2 may be absent, with the elongated solar receiver 2 A serving only as an elongated solar thermal receiver 2 T, and all the useful renewable energy extraction being through use of a thermodynamic cycle engine 78 E and/or a thermoelectric device 81 D, to produce mechanical and/or electrical output.
[0082] In the case of a closed-loop liquid cooling system, means for cooling a flowing liquid 33 MC may be provided between the outflow liquid transport pipe 33 O carrying hotter liquid 84 HL and eventually returning into the inflow liquid transport pipe 33 I as cooler liquid 84 CL, which means for cooling a flowing liquid 33 MC may include at least one of a liquid reservoir, a heat exchanger, a radiator and a cooling tower.
[0083] FIG. 5B shows a variant embodiment wherein an elongated solar photovoltaic receiver 2 and a separate and distinct elongated solar thermal receiver 2 T are both incorporated, in a stacked geometry and sequential liquid flow configuration. Thus in this embodiment two elongated solar receivers 2 A are provided, one being an elongated solar photovoltaic receiver 2 and the other a separate and distinct elongated solar thermal receiver 2 T.
[0084] In the illustrated embodiment the focal line 8 F of reflected sunrays 8 that are reflected and concentrated by the reflection and concentration surface 7 , is shown to be above both the stacked elongated solar receivers 2 A, at a location such that some of the reflected and concentrated sunrays fall on the downward facing solar cells of the elongated solar photovoltaic receiver 2 , while the balance of reflected and concentrated sunrays pass by the front and/or back sides (in this view) of the elongated photovoltaic receiver 2 and fall on the underside of the elongated solar thermal receiver 2 T with at higher concentration in suns than on the elongated photovoltaic receiver 2 (as the elongated solar thermal receiver 2 T has a linear axis location closer to the focal line 8 F than does the linear axis location of the elongated solar photovoltaic receiver 2 ).
[0085] FIG. 5B shows an embodiment of the invention in many respects similar to the embodiment of FIG. 5A , with a cooling system now comprising a liquid cooling system with liquid transport pipes 33 into and out of the solar photovoltaic module 1 . Cooler liquid 84 CL is transported by an inflow liquid transport pipe 33 I that originates at a location external to the solar photovoltaic module 1 , which inflow liquid transport pipe 33 I is then is routed through members of the solar photovoltaic module 1 to feed into the bottom end (left end in the view of FIG. 5A ) of the liquid heating tube means 31 H, where the liquid (e.g., a heated liquid coolant 84 C shown) flows upwards (to the right in the view of FIG. 5A ) while absorbing heat from the elongated solar receiver 2 A that is an elongated solar photovoltaic receiver 2 . This heat can be considered “waste heat” from the solar cells, but the “waste heat” nomenclature is not entirely appropriate as the heat can be put to use as will be explained in the following. At the (right) end of the elongated solar photovoltaic receiver 2 the liquid is an intermediate temperature liquid 84 IL, which serves as a preheated input liquid for the upper, left flowing portion of the liquid heating tube means 31 H that corresponds with the elongated solar thermal receiver 2 T. The liquid is heated to higher temperatures as it flows through the elongated solar thermal receiver 2 T, until it exits as a hotter liquid 84 HL at the left end of the elongated solar thermal receiver 2 T in this illustration. The hotter liquid 84 HL, which may also be mixed phase with some boiling occurring in some embodiments, exits the left end of the upper portion of the liquid heating tube means 31 H into an outflow liquid transport pipe 33 O, which outflow liquid transport pipe 33 O is routed through members of the solar photovoltaic module 1 and subsequently exits to a location external to the solar photovoltaic module 1 .
[0086] Note that the illustrated inflow liquid transport pipe 33 I and outflow liquid transport pipe 33 O traverse a dual-flow fluid rotary joint 53 RJ in this illustrated embodiment. It should be understood that in alternate embodiments a dual-flow rotary union or flexible concentric insulated hose fittings can alternatively be used to transport liquid across the rotating interfaces between (a) the nonrotating support structure 15 and (b) the rotatable portion 19 of the solar photovoltaic module 1 that includes the reflection and concentration surface 7 and the elongated solar receiver 2 A.
[0087] Note also that the inflow liquid transport pipe 33 I and the outflow liquid transport pipe 33 O would come down different A-frame leg members of the support structure 15 , fore and aft behind one another in this view, in a preferred embodiment. In an alternate embodiment both the inflow liquid transport pipe 33 I and the outflow liquid transport pipe 33 O could be routed down from the dual-flow fluid rotary joints 53 RJ along or inside a single leg member of the support structure 15 , within the spirit and scope of the invention.
[0088] The liquid cooling system of FIG. 5B , as in the embodiment of FIG. 5A , can effectively cool an elongated solar receiver 2 A that is an elongated solar photovoltaic receiver 2 and keep the photovoltaic cells or solar cells on the photovoltaic receiver at a lower temperature where they are not at risk of thermally induced damage and where they operate at higher electric power harvesting efficiency. The liquid cooling system can be either closed-loop or open-loop, and additional renewable energy will preferably be harvested by utilizing the temperature difference between the hotter liquid 84 HL and the cooler liquid 83 CL to run a thermodynamic cycle engine 78 E and a thermoelectric device 81 D, to produce mechanical and electrical output.
[0089] Preferably means for cooling a flowing liquid 33 MC (not shown) will be provided between the outflow liquid transport pipe 33 O carrying hotter liquid 84 HL and downstream of the thermodynamic cycle engine 78 E, before returning into the inflow liquid transport pipe 33 I as cooler liquid 84 CL, which means for cooling a flowing liquid 33 MC may include for example a liquid reservoir, a heat exchanger, or a radiator. In variant embodiments some or all of the heat from the hotter liquid 84 HL can be beneficially used for heating purposes, such as providing hot water for a home, building or swimming pool or hot tub, and/or for home or building heating, and/or for cooking and/or for industrial or commercial process heat. The thermodynamic cycle engine 78 E and thermoelectric device 81 D may be absent in some of these variant embodiments.
[0090] In the illustrated embodiment since both thermodynamic and thermoelectric energy harvesting means are included, the thermoelectric device 81 D serves as supplemental thermoelectric means 81 for harvesting additional power from the Sun, which supplemental thermoelectric means acts as means for directly harvesting electrical energy from the heat carried in the hotter liquid 84 HL.
[0091] FIG. 5B also illustrates generator means 80 connected to the mechanical energy output from the thermodynamic cycle engine 78 E, serving as generator means 80 for converting at least some of the mechanical energy into electrical energy. Electric power conditioning means 80 C are shown for conditioning electrical output from the various sources such as the downward facing solar cells of the elongated solar photovoltaic receiver 2 , the generator means 80 and the thermoelectric device 81 D. The electrical power conditioning means 80 C may perform one or more of electrical power conditioning functions known from the prior art, such as DC to or from AC conversion (e.g., inverter function), voltage changing, voltage and/or current stabilizing, phase control or changing, and/or other electrical power conditioning functions as are known from the prior art. The electrical power conditioning means 80 C may also serve as grid-engagement means for permitting said power output to feed back into an electrical power grid and at least one of slow, stop and reverse an electrical meter measuring net power flow from or to said electrical power grid.
[0092] The output from the electrical power conditioning means 80 C is transmitted by electric power transmission means 80 T such as electrical wire or cable, to users of electric power such as a home or building that may be off-grid or grid-connected, and may optionally feed back into an electric grid through a net-metering or other mechanism as known in the art.
[0093] FIG. 5B therefore illustrates a solar photovoltaic module 1 , wherein the electrical power means 20 further includes supplemental electrical power means 78 for harvesting additional power from the Sun 8 S, which supplemental electrical power means 78 comprises at least one of (i) supplemental thermodynamic power means 78 T for harvesting additional power from the Sun 8 S, wherein said heated cooling fluid 26 that is heated by heat 27 from said elongated photovoltaic receiver 2 serves at least in contributory part as a working fluid 94 for a thermodynamic cycle engine 78 E, which thermodynamic cycle engine 78 E serves as means for harvesting mechanical energy 79 M from heat energy 79 H including said heat 27 , with generator means 80 for converting at least some of said mechanical energy 79 M into electrical energy 79 E; and (ii) supplemental thermoelectric means 81 for harvesting additional power from the Sun 8 S, which supplemental thermoelectric means 81 acts as means for directly harvesting electrical energy 79 E from said heat 27 .
[0094] FIG. 5B also illustrates a solar photovoltaic module 1 , wherein the heated cooling fluid 26 comprises at least one of heated cooling water 84 W and heated liquid coolant 84 C; wherein at least one of a pump 30 and a thermosiphon 31 contributes to moving said heated cooling fluid 26 upward in said tilted fluid path 23 ; and further comprising at least one of:
[0000] (a) heat transfer means 32 for transferring heat from said heated cooling fluid 26 to a cooler environment 34 outside said solar photovoltaic module 1 ; and
(b) beneficial heat use means 77 for beneficially using heat from said heated cooling fluid 26 , which beneficial heat use means 77 comprises at least one of:
(i) supplemental electrical power means 78 for harvesting additional power from the Sun 8 S, which supplemental electrical power means 78 comprises supplemental thermodynamic power means 78 T for harvesting additional power from the Sun 8 S, wherein said heated cooling fluid 26 serves at least in contributory part as a working fluid 94 for a thermodynamic cycle engine 78 E, which thermodynamic cycle engine 78 E serves as means for harvesting mechanical energy 79 M from heat energy 79 H in said heated cooling fluid 26 , with generator means 80 for converting at least some of said mechanical energy 79 M into electrical energy 79 E;
(ii) supplemental electrical power means 78 for harvesting additional power from the Sun 8 S, which supplemental electrical power means 78 comprises supplemental thermoelectric means 81 for harvesting additional power from the Sun 8 S, which supplemental thermoelectric means 81 acts as means for directly harvesting electrical energy 79 E from heat energy 79 H in said heated cooling fluid 26 ; and
(iii) means for using heat energy 79 H in said heated cooling fluid 26 for providing beneficial heat (optional and not shown) to at least one of a building, a home, a swimming pool, a hot water tank, a heating appliance, a heating device, a dryer, a cooking appliance, a cooking device, an industrial process, and a chemical process.
[0095] FIG. 5C illustrates an embodiment similar to that of FIG. 5A , but with a thermosiphon cooling system for an elongated photovoltaic receiver 2 with the addition of a temperature stratified liquid holding tank 33 T between the outflow liquid transport pipe 33 O carrying hotter liquid 84 HL before returning into the inflow liquid transport pipe 33 I as cooler liquid 84 CL. Note that in this embodiment the structure of the liquid holding tank 33 T doubles as the portion of the support structure 15 that supports the upper (right in this view) part of the solar photovoltaic module 1 . A hot water outlet pipe 33 HO and a cold water inlet pipe 33 CI are also shown connected to the upper hot strata level and lower cool strata level respectively of the liquid holding tank 33 T. Hot water from the hot water outlet pipe 33 HO can be beneficially used as hot water per se and/or for heating purposes, such as providing hot water for a home, building or swimming pool or hot tub, and/or for home or building heating, and/or for cooking and/or for industrial or commercial process heat. The cold water inlet pipe 33 CI can supply cold water to replenish the water quantity in the liquid holding tank 33 T when hot water is taken out, or in the event of any leaks in the cooling system. It will be understood that other coolants or liquids could be used in lieu of water, in variant embodiments of the invention. It will also be understood that a simple thermosiphon system could be replaced by a pump-augmented thermosiphon system in variant embodiments, within the spirit and scope of the invention.
[0096] FIG. 5D shows a partial side view of an embodiment similar to that of FIG. 5B , with two elongated solar receivers 2 A being provided, one being an elongated solar photovoltaic receiver 2 and the other a separate and distinct elongated solar thermal receiver 2 T. However, in FIG. 5D the elongated solar thermal receiver 2 T is located below the elongated solar photovoltaic receiver 2 . In FIG. 5D the focal line 8 F of reflected sunrays 8 that are reflected and concentrated by the reflection and concentration surface 7 , is shown to be between the two stacked elongated solar receivers 2 A, at a location such that some of the reflected and concentrated sunrays fall on the elongated solar thermal receiver 2 T, while the balance of reflected and concentrated sunrays pass by the front or/and back sides (in this view) of the elongated solar thermal receiver 2 T, pass substantially through the focal line 8 F and then before expanding too much, fall on the downward facing solar cells of the elongated solar photovoltaic receiver 2 . A working fluid 94 94 that also serves as liquid coolant for the elongated solar photovoltaic receiver 2 , enters the solar photovoltaic module 1 pumped by a pump 30 into an inflow liquid transport pipe 33 I as cooler liquid 84 CL. The working fluid 94 then moves up (to the right in the figure) in liquid heating tube means 31 H that is typically a rectangular cross-section tube immediately adjacent to and heat-conductively connected to the back side of the elongated solar photovoltaic receiver 2 , where the working fluid 94 cools the solar cells and concurrently becomes a heated liquid coolant 84 C. Buoyancy forces acting on the heated liquid coolant 84 C assist the pump 30 in motivating and driving the flow to the right in the upper liquid heating tube means 31 H, as illustrated. The heated liquid coolant 84 C that is an intermediate temperature liquid 84 IL, serves as preheated working fluid 90 for the lower, left flowing portion of the liquid heating tube means 31 H that corresponds with the elongated solar thermal receiver 2 T. The liquid is heated to higher temperatures as it flows through the elongated solar thermal receiver 2 T, until it exits as a hotter liquid 84 HL at the left end of the elongated solar thermal receiver 2 T in this illustration. The hotter liquid 84 HL, exits the left end of the lower portion of the liquid heating tube means 31 H into an outflow liquid transport pipe 33 O. As in the embodiment of FIG. 5B , for the embodiment of FIG. 5D also, the liquid cooling system can be either closed-loop or open-loop, and additional renewable energy will preferably be harvested by utilizing the temperature difference between the hotter liquid 84 HL and the cooler liquid 83 CL to run a thermodynamic cycle engine 78 E, to produce mechanical and electrical output over and above the electrical output from the solar cells in the elongated solar photovoltaic receiver 2 .
[0097] FIG. 5E shows a partial side view of another embodiment similar to that of FIG. 5B , with two elongated solar receivers 2 A being provided, one being an elongated solar photovoltaic receiver 2 and the other a separate and distinct elongated solar thermal receiver 2 T stacked above it. However, in this variant the fluid flow is upward (to the right in the view of the Figure) in both the two liquid heating tube means 31 H, one associated each with the elongated solar photovoltaic receiver 2 and the elongated solar thermal receiver 2 T. This is accomplished through the use of a double-back or connecting tube 31 C, and offers the benefit of hot fluid buoyancy forces assisting in driving the thermosiphon effect in both of the two liquid heating tube means 31 H. A pump 30 is optional and not necessarily required for this variant embodiment.
[0098] FIG. 5F shows a partial side view of another embodiment similar to that of FIG. 5B , but with the liquid transport pipes 33 comprising the inflow liquid transport pipe 33 I and the outflow liquid transport pipe 33 O connect to the upper ends (left on this Figure as the local gravity vector 6 tilts the opposite way as in FIG. 5B ) rather than the lower ends of the two elongated solar receivers 2 A, one being an elongated solar photovoltaic receiver 2 and the other a separate and distinct elongated solar thermal receiver 2 T stacked above it. A pump 30 pushes the fluid down the lower liquid heating tube means 31 H (associated with the elongated solar photovoltaic receiver 2 ), and the heated liquid coolant 84 C that is an intermediate temperature liquid 84 IL, serves as preheated working fluid 90 for the upper, left flowing portion of the liquid heating tube means 31 H that corresponds with the elongated solar thermal receiver 2 T. The liquid is heated to higher temperatures as it flows (assisted by buoyancy force acting on the increasingly hot fluid) through the elongated solar thermal receiver 2 T, until it exits as a hotter liquid 84 HL at the left (upper) end of the elongated solar thermal receiver 2 T through the outflow liquid transport pipe 33 O in this illustration. The flows from the inflow liquid transport pipe 33 I and outflow liquid transport pipe 33 O can both go through a dual-flow fluid rotary joints 53 RJ (not shown), as in the embodiment of FIG. 5B .
[0099] FIGS. 6A and 6B show side views of combinations of plural solar modules 1 A of different types in sequence.
[0100] FIG. 6A shows two solar modules 1 A in sequence, where the module on the left of the Figure is a solar photovoltaic module 1 that is a first solar photovoltaic module 1 F; while the module on the right of the Figure is a solar thermal module 1 T that is a second solar module 1 S.
[0101] Cooler liquid 84 CL is transported by an inflow liquid transport pipe 33 I that is routed through members of the solar photovoltaic module 1 that is a first solar photovoltaic module 1 F, to feed into the bottom end (left end in the view of FIG. 6A ) of the liquid heating tube means 31 H, where the liquid flows upwards (to the right in the view of FIG. 6A ) while absorbing heat from the elongated solar receiver 2 A that is an elongated solar photovoltaic receiver 2 . This heat can be considered “waste heat” from the solar cells, but the “waste heat” nomenclature is not entirely appropriate as the heat can be put to use as will be explained in the following. At the (right) end of the elongated solar photovoltaic receiver 2 the liquid is an intermediate temperature liquid 84 IL, which serves as a preheated input liquid for the solar thermal module 1 T that is the second solar module 1 S, with the elongated solar thermal receiver 2 T.
[0102] The intermediate temperature liquid 84 IL is then heated to higher temperatures as it flows through the elongated solar thermal receiver 2 T in the second solar module 1 S, until it exits as a hotter liquid 84 HL at the right end of the elongated solar thermal receiver 2 T in this illustration. The hotter liquid 84 HL, which may also be mixed phase with some boiling occurring in some embodiments, exits the right end of the upper portion of the liquid heating tube means 31 H into an outflow liquid transport pipe 33 O, which outflow liquid transport pipe 33 O is routed through members of the second solar module 1 S and subsequently exits to a thermodynamic cycle engine 78 E. The thermodynamic cycle engine 78 E harvests additional renewable energy over and above electric energy harvested by the solar cells in the elongated solar photovoltaic receiver 2 in the first solar photovoltaic module 1 F. The thermodynamic cycle engine 78 E converts thermal energy from the hotter liquid 84 HL to mechanical energy, which in turn is converted to electrical energy by generator means 80 for converting at least some of the mechanical energy into electrical energy. Electric power conditioning means 80 C are shown for conditioning electrical output from the various sources such as the downward facing solar cells of the elongated solar photovoltaic receiver 2 , the generator means 80 and an optional thermoelectric device (not shown). The electrical power conditioning means 80 C may perform one or more of electrical power conditioning functions known from the prior art, such as DC to or from AC conversion (e.g., inverter function), voltage changing, voltage and/or current stabilizing, phase control or changing, and/or other electrical power conditioning functions as are known from the prior art. The output from the electrical power conditioning means 80 C is transmitted by electric power transmission means 80 T such as electrical wire or cable, to users of electric power such as a home or building that may be off-grid or grid-connected, and may optionally feed back into an electric grid through a net-metering or other mechanism as known in the art.
[0103] Preferably means for cooling a flowing liquid 33 MC, such as the illustrated liquid return pipe 33 R, will be provided downstream of the outflow liquid transport pipe 33 O carrying hotter liquid 84 HL in the second solar module 1 S, and downstream of the thermodynamic cycle engine 78 E, to transport liquid back into the inflow liquid transport pipe 33 I for the first solar photovoltaic module 1 F, as cooler liquid 84 CL. The means for cooling a flowing liquid 33 MC may include not just the liquid return pipe 33 R, but also may incorporate liquid reservoir, heat exchanger, or radiator elements.
[0104] In variant embodiments some of the heat from the hotter liquid 84 HL from the solar thermal module 1 T and/or downstream of the thermodynamic cycle engine 78 E, can be beneficially used for heating purposes such as providing hot water for a home, building, swimming pool or hot tub, and/or for home or building heating, and/or for cooking and/or for industrial or commercial process heat.
[0105] Note that the thermodynamic cycle engine 78 E may comprise at least one of a Brayton cycle engine, a Rankine cycle engine, a Stirling cycle engine, an Otto cycle engine, a hybrid cycle engine and an alternative thermodynamic cycle engine.
[0106] The embodiment of the invention shown in FIG. 6A illustrates a solar photovoltaic module 1 , further comprising a higher temperature second solar module 88 that is connected to said solar photovoltaic module 1 ;
[0000] wherein said heated cooling fluid 26 that is heated by heat 27 from said elongated photovoltaic receiver 2 in said solar photovoltaic module 1 , is piped by connecting pipe 89 to said second solar module 88 and used as preheated working fluid 90 for a thermodynamic cycle engine 78 E in said second solar module 88 ; and
wherein said second solar module 88 serves as second electrical power means 93 for harvesting additional power from the Sun 8 S, which second electrical power means 93 comprises at least one of
(i) second module thermodynamic power means 92 for harvesting additional power from the Sun 8 S, wherein said preheated working fluid 90 serves at least in contributory part as a working fluid 94 for said thermodynamic cycle engine 78 E, which thermodynamic cycle engine 78 E serves as means for harvesting mechanical energy 79 M from heat energy 79 H including said heat 27 , with generator means 80 for converting at least some of said mechanical energy 79 M into electrical energy 79 E; and
(ii) a combination of a higher temperature solar photovoltaic receiver 99 (optional but not shown) and second module thermodynamic power means 92 for harvesting additional power from the Sun 8 S, wherein said preheated working fluid 90 serves at least in contributory part as a working fluid 94 for said thermodynamic cycle engine 78 E, which thermodynamic cycle engine 78 E serves as means for harvesting mechanical energy 79 M from heat energy 79 H including said heat 27 , with generator means 80 for converting at least some of said mechanical energy 79 M into electrical energy 79 E.
[0107] FIG. 6B shows plural (three illustrated) solar modules 1 A in sequence, where the module on the top left of the Figure is a solar photovoltaic module 1 that is a first solar photovoltaic module 1 F; while the module on the top right of the Figure is a second solar module 1 S that is a solar thermal module 1 T combined with a higher temperature solar photovoltaic module 1 H with a higher temperature elongated solar photovoltaic receiver 2 H; and the rightmost module in the string of connected modules is shown on the bottom left of the Figure, connected through the Figure break line A-A, and comprises a downstream solar module 1 D that in this case is also a solar thermal module 1 T that is intended to operate at a still higher solar receiver temperature than the second solar module 1 S. Note that the higher temperature solar photovoltaic module 1 H in FIG. 6B includes a higher temperature solar photovoltaic receiver 99 (that was optional but not shown in FIG. 6A ). Note also that variant embodiments may have varying numbers of solar photovoltaic modules 1 , higher temperature solar photovoltaic modules 1 H, and downstream solar modules 1 D that are solar thermal modules 1 T, with combinations of series and optionally also parallel connectivity, within the spirit and scope of the invention.
[0108] In FIG. 6B , cooler liquid 84 CL is transported by an inflow liquid transport pipe 33 I that is routed through members of the solar photovoltaic module 1 that is a first solar photovoltaic module 1 F, to feed into the bottom end (left end in the view of FIG. 6B ) of the liquid heating tube means 31 H, where the liquid flows upwards (to the right in the view of FIG. 6B ) while absorbing heat from the elongated solar receiver 2 A that is an elongated solar photovoltaic receiver 2 . This heat can be considered “waste heat” from the solar cells, but the “waste heat” nomenclature is not entirely appropriate as the heat can be put to use as will be explained in the following. At the (right) end of the elongated solar photovoltaic receiver 2 the liquid is an intermediate temperature liquid 84 IL, which serves as a preheated input liquid for the second solar module 1 S that comprises a solar thermal module 1 T with an elongated solar thermal receiver 2 T, and also comprises a higher temperature solar photovoltaic module 1 H with a higher temperature elongated solar photovoltaic receiver 2 H. The higher temperature solar photovoltaic module 1 H will preferably utilize solar cells or photovoltaic receptors that are tolerant of higher temperatures without damage or excess loss of efficiency or performance. Examples of types of higher temperature solar cells include higher temperature silicon solar cells, gallium arsenide solar cells, and multijunction solar cells, without being limiting.
[0109] The intermediate temperature liquid 84 IL is then heated to higher temperatures as it flows through the elongated solar thermal receiver 2 T in the second solar module 1 S, until it exits as a hotter liquid 84 HL at the right end of the elongated solar thermal receiver 2 T in this illustration. The hotter liquid 84 HL, which may also be mixed phase with some boiling occurring in some embodiments, exits the right end of the upper portion of the liquid heating tube means 31 H into an outflow liquid transport pipe 33 O, which outflow liquid transport pipe 33 O is routed through members of the second solar module 1 S and subsequently exits to a downstream solar module 1 D and thereafter to a thermodynamic cycle engine 78 E.
[0110] In the embodiment of FIG. 6B , the downstream solar module 1 D is a solar thermal module 1 T that is intended to operate at a still higher solar receiver temperature than the second solar module 1 S, and increases the temperature of the working fluid as it transitions from being a hotter liquid 84 HL before the downstream solar module 1 D, to being a very hot liquid 84 VHL downstream of the downstream solar module 1 D. Plural downstream solar modules 1 D in series (not shown) can optionally be used to further increase the temperature of the working fluid, in conjunction with optimized design features for solar concentration in suns in each module, fluid flow rate control optimization, and optimized thermal insulation for piping that carries the very hot liquid 84 VHL. Different types of high temperature fluid can also be used in variant embodiments, including unpressurized or pressurized water based fluids, glycol type fluids, eutectic mixtures of biphenyl (C12H10) and diphenyl oxide (C12H10O) (such as “Dowtherm”), mixtures of tri- and di-aryl compounds (such as “Dowtherm G”), mixtures of alkylated aromatics or isomers of alkylated aromatics (such as “Dowtherm MX” or “Dowtherm J”), mixtures of diphenylethane and alkylated aromatics (such as “Dowtherm Q”), diaryl alkyls (such as “Dowtherm RP”), mixtures of C14-C30 alkyl benzenes (such as “Dowtherm T”), hot oils, molten salt fluids, alkali metals and combinations of fluids either together or connected in separate circuits connected by heat exchanger means.
[0111] In the embodiment of FIG. 6B , the very hot liquid 84 VHL downstream of the downstream solar module 1 D connects to an optional thermal energy storage system 79 T, which can store thermal energy for subsequent use to generate electric power when the solar modules are not working, e.g. during periods of cloud cover and night time periods. A variety of thermal energy storage systems 79 T, such as the use of molten salt thermal storage to cite just one example from the art, can be optionally and beneficially used.
[0112] In the embodiment of FIG. 6B , the very hot liquid 84 VHL downstream of the downstream solar module 1 D provides heat to a steam (Rankine) thermodynamic cycle engine 78 E at diminishing temperatures first a solar super-heater 29 SH and a solar re-heater 29 RH, then to a solar steam generator 29 SG, then to a solar pre-heater 29 PH, as illustrated. The high temperature fluid is no longer a very hot liquid 84 VHL, but substantially cooler as it enters a expansion vessel 29 EV, and thence into a fluid pump 30 F that returns the fluid into the liquid return pipe 33 R that feeds back into the inflow liquid transport pipe 33 I of the first solar photovoltaic module 1 F. The liquid return pipe 33 R may run through a water body, a heat exchanger, and/or a radiator to desirably further cool the liquid before it returns into the liquid return pipe 33 R.
[0113] The steam thermodynamic cycle engine 78 E that is illustrated pumps water with a water pump 30 W into the solar pre-heater 29 PH, where it is heated. The heated water then flows into the solar steam generator 29 SG where it is boiled to form steam. The steam then flows into the solar super-heater 29 SH, where it is super heated to a higher temperature and a high pressure. The super heated high pressure steam then drives a high pressure steam turbine 37 H, which converts heat energy into mechanical energy. The cooler lower pressure steam output from the high pressure steam turbine 37 H is then heated again in a solar re-heater 29 RH, which also obtains solar heat from a branch of the fluid that is the very hot liquid 84 VHL, as shown. The re-heated steam then drives a lower pressure turbine 37 L, and the output flow which may be a mixture of steam and water, flows into a condenser 37 C, optionally through a low pressure pre-heater (not shown) and a deaerator 37 D before feeding back into the water pump 30 W to restart the steam cycle of the steam thermodynamic cycle engine 78 E.
[0114] The thermodynamic cycle engine 78 E harvests additional renewable energy over and above electric energy harvested by the solar cells in the elongated solar photovoltaic receiver 2 in the first solar photovoltaic module 1 F and in the higher temperature elongated solar photovoltaic receiver 2 H in the higher temperature solar photovoltaic module 1 H. The thermodynamic cycle engine 78 E converts thermal energy from the very hot liquid 84 VHL to mechanical energy, which in turn is converted to electrical energy by generator means 80 for converting at least some of the mechanical energy into electrical energy. Electric power conditioning means 80 C are shown for conditioning electrical output from the various sources such as the downward facing solar cells of the elongated solar photovoltaic receiver 2 and higher temperature elongated solar photovoltaic receiver 2 H, the generator means 80 and an optional thermoelectric device (not shown). The electrical power conditioning means 80 C may perform one or more of electrical power conditioning functions known from the prior art, such as DC to or from AC conversion (e.g., inverter function), voltage changing, voltage and/or current stabilizing, phase control or changing, and/or other electrical power conditioning functions as are known from the prior art. In the illustrated embodiment, electrical energy storage means 80 S are also shown connected to the electrical power conditioning means 80 C. The electrical energy storage means 80 S may comprise for example a capacitor, a super capacitor, and ultra capacitor, or a flywheel connected to an electric motor-generator, or connected water reservoirs at different elevations with a pump-turbine and electric motor-generator in the connection, to cite some examples without limitation. The output from the electrical power conditioning means 80 C is transmitted by electric power transmission means 80 T such as electrical wire or cable, to users of electric power such as a home or building that may be off-grid or grid-connected, and may optionally feed back into an electric grid through a net-metering or other mechanism as known in the art.
[0115] In variant embodiments some of the heat from the very hot liquid 84 VHL and/or the hotter liquid 84 HL and/or intermediate temperature liquid 84 IL, can be beneficially used for heating purposes such as providing hot water for a home, building, swimming pool or hot tub, and/or for home or building heating, and/or for cooking and/or for industrial or commercial process heat.
[0116] The embodiments of the invention shown in each of FIG. 6A and FIG. 6B illustrate a connected array 17 of plural inflatable linear heliostatic concentrating solar modules 1 A including at least one inflatable linear cooled heliostatic concentrating solar photovoltaic module 1 , wherein:
[0000] each said solar module 1 A comprises an elongated solar receiver 2 A including a portion of substantially linear geometry 3 with a linear axis 4 ;
each said solar module 1 A comprises a reflection and concentration surface 7 for reflecting and concentrating sunrays 8 ;
each said solar module 1 A comprises a substantially enclosed elongated inflatable volume 10 comprising (i) an upper inflatable volume 10 U above said reflection and concentrating surface 7 , with a substantially transparent surface 11 above said upper inflatable volume 10 U, and further comprising (ii) a lower volume 14 below said reflection and concentrating surface 7 , with a bottom surface 13 below said lower volume 14 ;
each said solar photovoltaic module 1 includes cooling means 21 for removing excess heat 27 from its elongated solar receiver 2 A comprising an elongated solar photovoltaic receiver 2 , said cooling means 21 including a heated cooling fluid 26 that is heated by heat 27 from said elongated photovoltaic receiver 2 ;
further comprising connecting means 85 for connecting said plural inflatable linear heliostatic concentrating solar modules 1 A comprising at least one of (i) structural connecting means 85 S (not shown) for structurally connecting a first solar photovoltaic module 1 F to a second solar module 1 S and (ii) heated fluid connecting means 85 F (shown) for conveying heat energy in heated cooling fluid 26 outflow from a first solar photovoltaic module 1 F to a heated fluid stream 26 S inflow into a second solar module 1 S wherein the heated fluid stream 26 S is further heated by concentrated radiation energy received from the reflection and concentration surface 7 for reflecting and concentrating sunrays 8 in the second solar module 1 S;
further comprising support structure 15 for supporting said plural inflatable linear heliostatic concentrating solar modules 1 A on a supporting surface 16 ;
further comprising heliostatic control means 18 for aiming at least one rotatable portion 19 of said connected array 17 of plural inflatable linear heliostatic concentrating solar modules 1 A, as a function of at least one of time and other parameters, such that incoming sunrays 8 from a sunward direction 8 D will be reflected and concentrated by said reflection and concentration surfaces 7 , onto said elongated solar receivers 2 A at a concentration ratio of at least two suns; and
further comprising electrical power means 20 for collecting and transmitting electrical power from said elongated solar photovoltaic receiver 2 .
[0117] The embodiments of the invention shown in each of FIG. 6A and FIG. 6B also illustrate the connected array 17 of plural inflatable linear heliostatic concentrating solar modules 1 A of claim 3 , wherein the elongated solar receiver 2 A of the second solar module 1 S includes an elongated solar thermal receiver 2 T which heats the heated fluid stream 26 S to a higher temperature by using concentrated radiation energy received from the reflection and concentration surface 7 for reflecting and concentrating sunrays 8 in the second solar module 1 S;
[0000] and further comprising beneficial heat use means 77 for beneficially using heat from said heated fluid stream outflow 26 SO from said second solar module 1 S, which beneficial heat use means 77 comprises at least one of:
(i) supplemental electrical power means 78 for harvesting additional power from the Sun 8 S, which supplemental electrical power means 78 comprises supplemental thermodynamic power means 78 T (shown in FIG. 6A ) for harvesting additional power from the Sun 8 S, wherein said heated fluid stream outflow 26 SO from said second solar module 1 S that has been heated by the elongated solar thermal receiver 2 T serves at least in contributory part as a working fluid 94 for a thermodynamic cycle engine 78 E, which thermodynamic cycle engine 78 E serves as means for harvesting mechanical energy 79 M from heat energy 79 H in said heated fluid stream outflow 26 SO, with generator means 80 for converting at least some of said mechanical energy 79 M into electrical energy 79 E;
(ii) supplemental electrical power means 78 for harvesting additional power from the Sun 8 S, which supplemental electrical power means 78 comprises supplemental thermoelectric means 81 (shown in FIG. 6B ) for harvesting additional power from the Sun 8 S, which supplemental thermoelectric means 81 acts as means for directly harvesting electrical energy 79 E from heat energy 79 H in said heated fluid stream outflow 26 SO from said second solar module 1 S; and
(iii) beneficial means 79 B for using heat energy 79 H (shown in FIG. 6B ) in said heated fluid stream outflow 26 SO from said second solar module 1 S for providing beneficial heat to at least one of a building, a home, a swimming pool, a hot water tank, a heating appliance, a heating device, a dryer, a cooking appliance, a cooking device, an industrial process, and a chemical process.
[0118] Note that a thermodynamic cycle engine 78 E may comprise at least one of a Brayton cycle engine, a Rankine cycle engine, a Stirling cycle engine, an Otto cycle engine, a hybrid cycle engine, and an alternative cycle engine.
[0119] FIG. 7 shows a side view of an embodiment of the invention that has a solar module 1 A with a liquid cooling system, where the solar module 1 A is a solar photovoltaic module 1 similar to the first solar photovoltaic module 1 F shown in FIG. 6A . The embodiment of FIG. 7 uses a liquid cooling system, with a cooling system now comprising a system with liquid transport pipes 33 into and out of the solar photovoltaic module 1 . Cooler liquid 84 CL is transported by an inflow liquid transport pipe 33 I that originates at a location external to the solar photovoltaic module 1 , which inflow liquid transport pipe 33 I is then is routed through members of the solar photovoltaic module 1 to feed into the bottom end (left end in the view of FIG. 7 ) of the liquid heating tube means 31 H, where the liquid (e.g., a heated liquid coolant 84 C shown) flows upwards (to the right in the view of FIG. 5A ) while absorbing heat from the elongated solar receiver 2 A (that is an elongated solar photovoltaic receiver 2 ) and increasing in temperature. The hotter liquid 84 HL, exits the top end (right end in the view of FIG. 5A ) of the liquid heating tube means 31 H into an outflow liquid transport pipe 33 O, which outflow liquid transport pipe 33 O is routed through members of the solar photovoltaic module 1 and subsequently exits to a location external to the solar photovoltaic module 1 . For this embodiment where the hotter liquid 84 HL is used to heat water in a water tank for various beneficial purposes, the preferred but not limiting temperature range for the hotter liquid is between 65 degrees C. and 85 degrees C. inclusive. A sensor 65 that is a temperature sensor 65 T can optionally be provided to measure the temperature of the hotter liquid 84 L, and can feed a sensor signal into a control system that controls an optional pump 30 that is a fluid pump 30 F, to pump fluid at an appropriate rate such that the sensed temperature is at a desired value (e.g., some value selected between 65 and 85 degrees C., without being limiting).
[0120] Note that the illustrated inflow liquid transport pipe 33 I and outflow liquid transport pipe 33 O could both include fluid flow rotary joints including an axle member. It should be understood that in alternate embodiments rotary joints, rotary unions or flexible hose fittings can alternatively be used to transport liquid across the rotating interfaces between (a) the nonrotating support structure 15 and (b) the rotatable portion 19 of the solar photovoltaic module 1 that includes the reflection and concentration surface 7 and the elongated solar receiver 2 A.
[0121] The liquid cooling system of FIG. 7 can effectively cool an elongated solar receiver 2 A that is an elongated solar photovoltaic receiver 2 and keep the photovoltaic cells or solar cells on the photovoltaic receiver at a lower temperature where they are not at risk of thermally induced damage and where they operate at higher electric power harvesting efficiency (typically no more than 85 degrees C. for nonspecialty silicon solar cells, without being limiting). The liquid cooling system can be either closed-loop (shown) or open-loop, and use water or other liquid coolant (shown, so as to avoid freezing during subfreezing weather conditions), as known from the prior art of many variant liquid cooling systems. Additional plumbing elements known from the art, such as valves, overflow valves, pressure relief valves, filters, traps, means for eliminating trapped air bubble, flow control devices such as faucet controls, drains, junctions and other elements can optionally also be provided, within the spirit and scope of the invention.
[0122] With a closed-loop liquid cooling system, means for cooling a flowing liquid 33 MC can be provided between the outflow liquid transport pipe 33 O carrying hotter liquid 84 HL and eventually returning into the inflow liquid transport pipe 33 I as cooler liquid 84 CL, which means for cooling a flowing liquid 33 MC may include at least one of a liquid reservoir (water tank 33 W shown acts as a heat sink or heat absorber), a radiator 31 R (shown), a heat exchanger and a cooling tower. FIG. 7 shows beneficial means 79 B for using heat energy 79 H in the heated fluid stream (hotter liquid 84 HL) for providing beneficial heat to at least one of a hot water tank (water tank 33 W shown, being heated by heat transfer means 32 comprising the illustrated spiral tube heat transfer means 32 ST), a home, a building, an in-floor heating system, a radiator heating system, a swimming pool, a hot tub, a jacuzzi, a spa, a sauna, a heating appliance, a heating device, a dryer, a cooking appliance, a cooking device, an industrial process, and a chemical process. The illustrated water tank 33 W is shown with the addition of a (non-solar) alternate heater means 32 A for heating water, to heat water in the water tank 33 W during periods of cloud cover or night time periods when the solar module 1 A is not collecting solar energy. The alternate heater means 32 A may comprise an electric water heater or gas water heater, for example.
[0123] FIGS. 8A and 8B show plan views of embodiments with connected arrays 17 of plural inflatable linear heliostatic concentrating solar modules 1 A.
[0124] FIG. 8A shows a plan view of an embodiment of the invention with a connected array 17 of eight inflatable linear heliostatic concentrating solar modules 1 A. The 8 solar modules are shown in a substantially linear array, but it should be understood that varying numbers of modules and varying geometric arrangements of the connected array are possible within the spirit and scope of the invention.
[0125] The illustrated connected array 17 has solar modules 1 A including a pair of solar photovoltaic modules 1 that are first solar photovoltaic modules 1 F at the left end of the connected array 17 , and another pair of solar photovoltaic modules 1 that are first solar photovoltaic modules 1 F at the right end of the connected array 17 . Each first solar photovoltaic module uses liquid cooled solar cells that harvest electric power from concentrated sunlight, with the liquid cooling system using an input fluid stream that is cooler liquid 84 CL (pumped by at least one pump 30 ), and an output fluid stream that is intermediate temperature liquid 84 IL, as illustrated.
[0126] Moving inward in the connected array 17 from the first solar photovoltaic modules 1 F, the next pair of solar modules 1 A comprise second solar modules 1 S which are higher temperature second solar modules 88 , and that comprise higher temperature solar photovoltaic modules 1 H that are also solar thermal modules 1 T. Each higher temperature solar photovoltaic module 1 H uses a liquid cooling with an input fluid stream that is intermediate temperature liquid 84 IL coming from the first solar photovoltaic modules 1 , with the fluid stream getting heated by “waste heat” from the higher temperature solar photovoltaic module 1 H and leaving as a hotter liquid 84 HL. The higher temperature solar photovoltaic modules 1 H will preferably utilize solar cells or photovoltaic receptors that are tolerant of higher temperatures without damage or excess loss of efficiency or performance. Examples of types of higher temperature solar cells include higher temperature silicon solar cells, gallium arsenide solar cells, and multijunction solar cells, without being limiting.
[0127] Moving inward in the connected array 17 from the second solar modules 15 , two more solar modules 1 A are shown, which are downstream solar modules 1 D that are solar thermal modules 1 T that are intended to operate at a still higher solar receiver temperature than the second solar modules 1 S. The downstream solar modules 1 D increase the temperature of the working fluid as it transitions from being a hotter liquid 84 HL before said downstream solar modules 1 D, to being a very hot liquid 84 VHL downstream of said downstream solar modules 1 D. Plural downstream solar modules 1 D in series (not shown) can optionally be used to further increase the temperature of the flowing working fluid, in conjunction with optimized design features for solar concentration in suns in each module, fluid flow rate control optimization, and optimized thermal insulation for piping that carries the very hot liquid 84 VHL.
[0128] The very hot liquid carries heat energy harvested from reflected concentrated sunlight from the Sun, at a very hot temperature to a thermodynamic cycle engine 78 E that converts the heat energy 79 H into mechanical energy 79 M. The efficiency of the thermodynamic cycle is high, as the temperature of the input heat energy is very hot, as is well known from the science of thermodynamics. The thermodynamic cycle engine 78 E may comprise at least one of a Brayton cycle engine, a Rankine cycle engine, a Stirling cycle engine, an Otto cycle engine, a hybrid cycle engine and an alternative thermodynamic cycle engine. Mechanical energy 79 M is converted by generator means 80 for generating electricity, into electrical energy 79 E, that is subsequently combined with electrical energy from other sources and appropriately conditioned, by electric power conditioning means 80 C. The other sources of electrical energy feeding into the electric power conditioning means 80 C include electricity harvested by the solar cells in each of the solar photovoltaic modules 1 and higher temperature solar photovoltaic modules 1 H, as well as electricity harvested by the illustrated supplemental thermoelectric means 81 that harvests additional energy and power from the working fluid outflow from the thermodynamic cycle engine 78 E before it flows into means for cooling a flowing liquid 33 MC. Conditioned electric power is output from the electric power conditioning means 80 C via electric power transmission means 80 T, for transmission eventually connecting to users of electric power.
[0129] FIG. 8B shows a plan view of an embodiment of the invention similar to that of FIG. 8A , but showing two laterally separated connected arrays 17 of eight inflatable linear heliostatic concentrating solar modules 1 A each, in a substantially linear array arranged substantially along a North-South orientation, with the lateral separation in an East-West orientation, as illustrated. The orientation of the illustrated view is with North 95 towards the right, as illustrated, for a Northern Hemisphere installation. An analogous illustration for the Southern Hemisphere would have South to the right. Note that the two laterally separated connected arrays 17 can also be considered as a single two-dimensional array.
[0130] The lateral separation of the two laterally separated connected arrays 17 greatly minimizes any shadowing of solar modules 1 A in one array from other solar modules 1 A in the other array, for morning and evening conditions when the Sun is at very low elevation angle. North-South staggering of the solar modules 1 A in adjacent laterally separated connected arrays 17 may optionally be provided to further reduce shadowing effects in different geographic locations. The land in the area of lateral separation, in one preferred embodiment, can be a field 96 . The field 96 could be a grazing field, an agricultural field planted with crops, or even a parking lot. An access road 97 could optionally be provided as illustrated, for purposes that may vary from maintenance and installation access for the solar modules 1 A, to transportation purposes.
[0131] Embodiments of the class of FIG. 8B are well suited for application on farm land or other low-height land uses, such as recreational land, parks and parking lots. For a typical agricultural land implementation, large fields can be divided into plural long North-South oriented fields with rows of solar modules 1 A between them. A grid of North-South and also some widely spaced East-West access roads or unpaved roads can optionally be provided. The solar module rows may optionally be fenced around. In this manner a substantial majority (e.g., 60% to 99%) of the land can still be beneficially used for the original intended (e.g., agricultural) purpose, while the balance of the land is efficiently and effectively used for solar energy harvesting with very minimal shadowing effects.
[0132] While a certain combination and arrangement of solar photovoltaic modules 1 , higher temperature solar photovoltaic modules 1 H, and downstream solar modules 1 D that are solar thermal modules 1 T are shown, it will be understood that other combinations and arrangements are possible within the spirit and scope of the invention. Similarly, while a certain number and arrangement of thermodynamic cycle engine(s) 78 E generator means 20 are shown, varying number(s) and arrangements are possible within the spirit and scope of the invention, with greater or lesser distribution or federation.
[0133] FIGS. 9A through 9H show side views of alternate embodiments of the invention.
[0134] FIG. 9A shows a side view of an embodiment similar to that of FIG. 1A , but with a less elongated solar photovoltaic module 1 . Without being limiting, for comparison if the embodiment of FIG. 1A has an elongated photovoltaic receiver 2 that is about 20 feet long, the embodiment of FIG. 9A has an elongated photovoltaic receiver that is about 9 feet long. And without being limiting, for comparison where the embodiment of FIG. 1A has an elongated photovoltaic receiver 2 that is tilted at a latitude tilt of about 35 degrees, the embodiment of FIG. 9A has an elongated photovoltaic receiver that is tilted at a latitude tilt of only 5 degrees, representative of a much more near-Equatorial location.
[0135] FIG. 9B shows a side view of an embodiment similar to that of FIG. 9A , but wherein the embodiment of FIG. 9B has an elongated photovoltaic receiver that is tilted at a latitude tilt of 55 degrees, representative of a much more near-polar location. The embodiment of FIG. 9B requires a tall frame tilting structure 74 to maintain the 55 degree latitude tilt, as illustrated. With the steep tilt of the cooling means 21 , a version with just hot gas buoyancy induced flow and no fan would certainly be a possible variant embodiment.
[0136] FIG. 9C shows a side view of an embodiment similar to that of FIG. 9B , but wherein the support structure 15 supports the solar photovoltaic module 1 with a cantilevered support from one end of the device, the left end in the illustrated view.
[0137] FIG. 9D shows a side view of an embodiment similar to that of FIG. 9B , but wherein the frame tilting structure 74 comprises at least one of a motorized and an actuated controllable height frame tilting structure 74 MAC, here being both a controllable height frame tilting structure 74 C and a variable height adjustable frame tilting structure 74 V. Variable tilt angles could be used for optimized performance at different locations in different seasons, or optionally for two-axis heliostatic tracking.
[0138] FIG. 9E shows a side view of an embodiment of the invention which is an inflatable linear heliostatic concentrating solar module 1 A (illustrated is a solar photovoltaic module 1 similar to that of FIG. 2A , without limitation), now mounted on a roof surface 16 R on a building 98 , and hence not necessarily requiring a frame tilting structure 74 . The roof preferably has a slope 16 SL towards the South in Northern Hemisphere installations (shown), and a slope towards the North 95 in Southern Hemisphere installations (not shown). The slope would ideally match the latitude, but clearly this concept of rooftop mounting can work with variations in roof slope and direction through the use of adaptor fittings or legs.
[0139] FIG. 9F shows a side view of an embodiment of the invention with a connected array of plural inflatable linear heliostatic concentrating solar modules 1 A including at least one inflatable linear cooled heliostatic concentrating solar photovoltaic module 1 are mounted on a serrated shape roof surface 16 R on a building 98 , and hence not necessarily requiring frame tilting structures 74 . The roof preferably has slopes 16 SL towards the South in Northern Hemisphere installations (shown), and a slope towards the North 95 in Southern Hemisphere installations (not shown). The slope would ideally match the latitude, but clearly this concept of rooftop mounting can work with variations in roof slope and direction through the use of adaptor fittings or legs. The embodiment of FIG. 9F can incorporate the various features earlier described in the context of FIGS. 6A and 6B . Also, in addition to the heated fluid connecting means 85 F between the plural inflatable linear heliostatic concentrating solar modules 1 A, FIG. 9F shows connecting means 85 for connecting said plural inflatable linear heliostatic concentrating solar modules 1 A comprising also structural connecting means 85 S (through the structure of the building 98 as illustrated) for structurally connecting a first solar photovoltaic module 1 F to a second solar module 1 S.
[0140] FIG. 9G shows an embodiment similar to that of FIG. 9E , but supported on a water surface 16 W instead of on a roof surface 16 R. The support structure 15 now includes 15 F floating support structure 15 F and underwater tethers 15 T.
[0141] FIG. 9H shows a side view of an embodiment of the invention which is an inflatable linear heliostatic concentrating solar module 1 A (illustrated is a solar photovoltaic module 1 similar to that of FIG. 1A , without limitation), now supported by support structure 15 on a supporting surface 16 (that may be a land or water surface) without tilt and, and therefore not requiring a frame tilting structure 74 . The device can be mounted with either a North-South orientation or an East-West orientation along with heliostatic control means 18 to follow the apparent motion of the Sun so as to reflect and concentrate sunrays 8 on the elongated solar photovoltaic receiver 2 over a period of operating solar time. The embodiment shown has some left to right slope on either side of the reflection and concentration surface 7 as shown, so that (i) the focal line of reflected sunrays 8 F and (ii) the linear axis 4 of the portion of substantially linear geometry 3 of the elongated solar photovoltaic receiver 2 and (iii) the orientation 24 of the tilted fluid path 23 , all also have some left to right slope, as shown in the Figure. Thus the illustrated embodiment has cooling means 21 including a tilted fluid path 23 that is tilted up in an orientation 24 including a component along said linear axis 4 , wherein buoyancy force acting on heated cooling fluid 26 that is heated by heat 27 from said elongated photovoltaic receiver 2 , contributes to moving said heated cooling fluid 26 upward in said tilted fluid path 23 . Left and right side cooling streams converge and exhaust through a central exhaust hood 22 E, as illustrated.
[0142] FIG. 9H therefore shows a tilted inflatable linear cooled heliostatic concentrating solar photovoltaic module 1 , comprising: an elongated solar photovoltaic receiver 2 including a portion of substantially linear geometry 3 with a linear axis 4 in its installed orientation being tilted up from a horizontal plane 5 that is perpendicular to the local gravity vector 6 ; a reflection and concentration surface 7 for reflecting and concentrating sunrays 8 ; an elongated upper inflatable volume 9 above said reflection and concentrating surface 7 , with a substantially transparent surface 11 above said upper inflatable volume 9 ; an elongated lower inflatable volume 12 below said reflection and concentrating surface 7 , with a bottom surface 13 below said lower inflated volume 12 ; support structure 15 for supporting said solar photovoltaic module 1 on a supporting surface 16 ; heliostatic control means 18 for aiming a rotatable portion 19 of said solar photovoltaic module 1 as a function of at least one of time and other parameters, such that incoming sunrays 8 from a sunward direction 8 D will be reflected and concentrated by said reflection and concentration surface 7 , onto said elongated solar photovoltaic receiver 2 at a concentration ratio of at least two suns; electrical power means 20 for collecting and transmitting electrical power from said elongated solar photovoltaic receiver 2 ; and cooling means 21 for removing excess heat 27 from said elongated solar photovoltaic receiver 2 , said cooling means 21 including a tilted fluid path 23 that is tilted up in an orientation 24 including a component along said linear axis 4 , wherein buoyancy force acting on heated cooling fluid 26 that is heated by heat 27 from said elongated photovoltaic receiver 2 , contributes to moving said heated cooling fluid 26 upward in said tilted fluid path 23 .
[0143] FIG. 9H also shows a tilted inflatable linear cooled heliostatic concentrating solar photovoltaic module 1 , comprising: an elongated solar photovoltaic receiver 2 including a portion of substantially linear geometry 3 with a linear axis 4 in its installed orientation being tilted up from a horizontal plane 5 that is perpendicular to the local gravity vector 6 ; a reflection and concentration surface 7 for reflecting and concentrating sunrays 8 ; a substantially enclosed elongated inflatable volume 10 comprising (i) an upper inflatable volume 10 U above said reflection and concentrating surface 7 , with a substantially transparent surface 11 above said upper inflatable volume 10 U, and further comprising (ii) a lower volume 14 below said reflection and concentrating surface 7 , with a bottom surface 13 below said lower volume 14 ; support structure 15 for supporting said solar photovoltaic module 1 on a supporting surface 16 with said linear axis 4 in its installed orientation being tilted up from a horizontal plane 5 that is perpendicular to the local gravity vector 6 ; heliostatic control means 18 for aiming a rotatable portion 19 of said solar photovoltaic module 1 as a function of at least one of time and other parameters, such that incoming sunrays 8 from a sunward direction 8 D will be reflected and concentrated by said reflection and concentration surface 7 , onto said elongated solar photovoltaic receiver 2 at a concentration ratio of at least two suns; electrical power means 20 for collecting and transmitting electrical power from said elongated solar photovoltaic receiver 2 ; and cooling means 21 for removing excess heat 27 from said elongated solar photovoltaic receiver 2 , said cooling means 21 including a tilted fluid path 23 that is tilted up in an orientation 24 including a component along said linear axis 4 , wherein buoyancy force acting on heated cooling fluid 26 that is heated by heat 27 from said elongated photovoltaic receiver 2 , contributes to moving said heated cooling fluid 26 upward in said tilted fluid path 23 .
[0144] FIGS. 10A through 10J show partial cross-sectional views of alternate embodiments of an inflatable linear heliostatic concentrating solar module 1 A, illustrated as a solar photovoltaic module 1 , without limitation.
[0145] FIG. 10A shows a partial cross-sectional view of an embodiment very similar to that shown in FIG. 1B , with the notable change being the use of suitably angled and shaped reflective flanges 7 RF on either side of the downward facing solar cells 36 , so that in the event of motion or distortion of various members of the device (e.g., such as the reflection and concentration surface 7 ), reflected light that spills laterally off to the right or left sides of the solar cells 36 will be re-reflected (at least to some extent) by the reflective flanges 7 RF to fall on the solar cells 36 and contribute to solar energy harvesting without spillage loss.
[0146] FIG. 10B shows a partial cross-sectional view of an embodiment similar to that shown in FIG. 10A , with a substantially circular inflatable envelope cross-section shape made by the substantially transparent surface 11 and the bottom surface 13 in conjunction.
[0147] FIG. 10C shows a partial cross-sectional view of an embodiment similar to that shown in FIG. 10 A, with a “double bubble” piecewise circular inflatable envelope cross-section shape, analogous to the “double bubble” piecewise circular cross-sections used on some aircraft pressurizable fuselages. The embodiment also shows the substantially transparent surface 11 contacting the bottom smooth flange surfaces of the two reflective flanges 7 RF.
[0148] FIG. 10D shows a partial cross-sectional view of an embodiment similar to that shown in FIG. 10C , with the substantially transparent surface 11 split into two separate pieces with upper ends fastened and/or bonded to the bottom smooth flange surfaces of the two reflective flanges 7 RF, and no transparent surface in the reflected light path between the reflection and concentration surface 7 and the downward facing solar cells 36 . FIG. 10D also shows a “triple bubble” piecewise circular inflatable envelope cross-section shape, with the left and right bottom lobes meeting at a location held in place by a ballast beam 58 B.
[0149] FIG. 10E shows a partial cross-sectional view of an embodiment similar to that shown in FIG. 10B , with an approximately elliptical (in lieu of circular) inflatable envelope cross-section shape made by the substantially transparent surface 11 and the bottom surface 13 in conjunction, as shown. Periodic framing members (not shown) can help maintain the approximately elliptical shape even when the upper and lower inflatable chambers are inflated to an above ambient pressure (with the upper chamber pressure typically being held a bit higher than the lower chamber pressure) with small or modest amounts of inflation induced pillowing between the framing members (not shown).
[0150] FIG. 10F shows a partial cross-sectional view of an embodiment with a substantially enclosed elongated inflatable volume 10 comprising (i) an upper inflatable volume 10 U above the reflection and concentrating surface 7 , with a substantially transparent surface 11 above the upper inflatable volume 10 U, and further comprising (ii) a lower volume 14 (with a frame 7 F) below the reflection and concentrating surface 7 , and with a bottom surface 13 below the lower volume 14 . The illustrated frame 7 F maintains the reflection and concentrating surface 7 in shape and resists shape changing forces arising from pressurization of the upper inflatable volume 10 U, and protects it from harm from any objects impacting the bottom surface 13 (as for example hail when the device is in an inverted safety stow configuration).
[0151] FIG. 10G shows a partial cross-sectional view of an embodiment similar to that shown in FIG. 10D , with a “triple bubble” piecewise circular inflatable envelope cross-section shape, with the left and right bottom lobes meeting at a location held in place by a ballast beam 58 B. However, the embodiment of FIG. 10G shows the inflatable volumes bounded by the left and right bottom lobes respectively, as being separated by a membrane 48 M that is an internal substantially impermeable central membrane.
[0152] FIG. 10H shows a partial cross-sectional view of a piecewise circular inflatable envelope cross-section shape, with less tall inflatable volumes above and below the reflection and concentration surface 7 , as compared with the circular inflatable envelope of FIG. 10B . An elongated solar thermal receiver 2 T is provided near the focal line of reflected sunrays 8 F, and in addition a double row 35 D of solar cells 36 is provided above the elongated solar thermal receiver 2 T, with the two rows separated so as to avoid shadowing losses on to the solar cells 36 on each row. Structure connecting the double row 35 D and the solar thermal receiver 2 T is not shown in this partial cross-sectional view. The heated cooling fluid 26 that cools the dual elongated solar photovoltaic receivers 2 can be optionally be used as a preheated input fluid flowing into the elongated solar thermal receiver 2 T.
[0153] FIG. 10I shows a partial cross-sectional view of an embodiment similar to that shown in FIG. 10A , with a substantially vertically oriented (when the Sun is at solar noon) double-sided elongated solar photovoltaic receiver 2 D that receives reflected and concentrated sunlight on both sides, from the reflection and concentration surface 7 , as shown. The double-sided elongated solar photovoltaic receiver 2 D acts naturally to some extent as a cooling fin, but additional cooling means as described elsewhere in this specification, may also optionally be provided. In variant embodiments the double-sided elongated solar photovoltaic receiver 2 D may be partially or wholly below the substantially transparent surface 11 , instead of above as illustrated.
[0154] FIG. 10J shows a partial cross-sectional view of an embodiment similar to that shown in FIG. 10B , with a wedge-shaped elongated solar photovoltaic receiver 2 with solar cells 36 on both the downward facing faces of the wedge shape, as illustrated. While air cooling using an air cooling pipe 22 A is shown in the illustrated embodiment of FIG. 10J , liquid cooling can be provided in variants thereof.
[0155] FIGS. 11A through 11D show partial side views of the right end structure 45 R portion of the left and right end structures 45 .
[0156] FIG. 11A shows a partial side view of the same right end structure 45 R as shown and described earlier with reference to FIG. 1A . The illustrated right end structure 45 comprises at least one of (i) a beam member 46 B (shown), (ii) a wheel member 46 W (shown), (iii) a rim member 46 R (shown), (iv) plural spoke members 46 S (shown), (v) a hub member 46 H (shown), (vi) an axle member 46 A (shown), (vii) a plate member 46 P (not shown), (viii) a dished plate member 46 D (not shown) and (ix) a second beam member 46 SB (not shown) substantially perpendicular to said beam member 46 B. The lower end region 45 E of the right end structure 45 R portion of the left and right end structures 45 is also visible, and as shown the right end structure 45 R is part of the rotatable portion 19 of the solar module, rotatable around the axle member 46 A (shown) by the heliostatic control means 18 (not visible in this partial side view, but shown and described earlier in the context of FIG. 1A ).
[0157] FIG. 11B shows a partial side view of the right end structure 45 R portion of the left and right end structures 45 , wherein the right end structure 45 R comprises a plate member 46 P.
[0158] FIG. 11C shows a partial side view of the right end structure 45 R portion of the left and right end structures 45 , wherein the right end structure 45 R comprises a dished plate member 46 D.
[0159] FIG. 11D shows a partial side view of the right end structure 45 R portion of the left and right end structures 45 , wherein the right end structure 45 R comprises a beam member 46 B that is shown in a substantially vertical orientation when the solar module is operational at solar noon (e.g., an orientation similar to that shown in FIG. 1A ), and further comprises a second beam member 46 SB that is shown in a substantially horizontal orientation (in to and out of the page and substantially perpendicular to and integral with or attached to the beam member 46 B). The second beam member 46 SB is preferably designed to attach or mate with the right end member of the frame 7 F (not shown) that surrounds the reflection and concentration surface 7 (not shown), at an interface that serves as structural connection means 43 , which structural connection means 43 is shown in both FIG. 11D and at the corresponding location in FIG. 1A .
[0160] FIGS. 12 and 13 show partial side views of deployed and shipping configurations of an upper module 1 U portion of an inflatable linear heliostatic concentrating solar module 1 A that is a solar photovoltaic module 1 .
[0161] FIG. 12 shows a partial side view of the deployed configuration of an upper module 1 U portion of a modular design embodiment of an inflatable linear heliostatic concentrating solar module 1 A that is a solar photovoltaic module 1 . The illustrated elongated solar receiver 2 A is an elongated solar photovoltaic receiver 2 . The features of the upper module 1 U correspond with those shown in the embodiment of FIG. 1A , without being limiting. The illustrated left end structure 45 L portion and right end structure 45 R portion of the left and right end structures 45 , correspond with the cross beam design illustrated in FIG. 11D , with both a beam member 46 B and a second beam member 46 SB on each end structure. An optional substantially circular rim member 46 R is shown ringing around the beam member 46 B and the crosswise second beam member 46 SB, for both the illustrated left end structure 45 L and right end structure 45 R. The left and right end structures 45 are attached to the upper beam structure 40 by hinges 39 , as illustrated. Strong, load-bearing, two position lockable hinges will preferably be provided. One or both of the end rim members 46 R (prefer the left end rim member when only one is used) are preferably designed to be engaged by a control drive element (not shown) such as a belt 63 B or a chain 63 H or a cable 63 C or a toothed belt 63 TB or a belt with periodic holes 63 BP or a toothed cable 63 TC, which serve as the actuation means for the heliostatic control means 18 (not shown in this partial side view Figure) to rotate a rotatable portion 19 of the solar module including the upper module 1 U, around an axis going through the axle members 46 A. The ballast beam 58 B part of the upper module 1 U is not shown in FIG. 12 , but can be readily attached to the bottom ends of the beam members 46 B, as in FIG. 1A .
[0162] FIG. 13 shows a partial side view of the same embodiment as FIG. 12 , with a compact shipping configuration of the upper module 1 U portion of a modular design embodiment of an inflatable linear heliostatic concentrating solar module 1 A that is a solar photovoltaic module 1 . The compact shipping configuration is obtained by folding the left end structure 45 L and right end structure 45 R inwards around the hinges 39 so that they stow compactly approximately adjacent to the upper beam structure 40 , as illustrated. FIG. 13 shows compact shipping means 42 for shipping said solar photovoltaic module 1 in a reduced volume configuration in a shipping container 25 (to be shown in FIGS. 17 and 18 following), which compact shipping means 42 comprises at least one of (a) disconnectable connecting means 85 D (shown, being the structural connection means 43 ) providing means for easy disconnection of the upper module 1 U and the reflector module 1 R and the lower module 1 L for more compact shipping; (b) folding means 86 (shown, being the hinges 39 ) in at least one of the upper module 1 U (shown) and the reflector module 1 R and the lower module 1 L for folding constituent members for more compact shipping; and (c) provision of deflation means 76 M (not applicable to the upper module 1 U) for deflating the substantially enclosed elongated inflatable volume 10 for more compact shipping.
[0163] The embodiment of FIGS. 12 and 13 can be constructed in many varying scales within the spirit and scope of the invention. However, as selected representative scales, a first scale would have an elongated solar photovoltaic receiver 2 that is about 20 feet long, and a second scale would have an elongated solar photovoltaic receiver that is about 40 feet long. Two modules of the first scale could fit lengthwise end to end, with compact protective packaging, within a representative standard 45 foot hi-cube intermodal freight shipping container, with representative exterior dimensions of 45′ 0″×8′ 0″×9′ 6″ and representative interior dimensions of 44′ 4″×7′ 8.59375″×8′ 9.9375″. One module of the second scale could fit lengthwise, with compact protective packaging, within that same representative standard 45 foot hi-cube intermodal freight shipping container.
[0164] FIGS. 14 and 15 show partial side views of deployed and shipping configurations of a reflector module 1 R portion of an inflatable linear heliostatic concentrating solar module 1 A that is a solar photovoltaic module 1 , similar to that shown and described in detail earlier in the context of FIG. 1A . The reflector module 1 R shown in FIGS. 14 and 15 is attachable to the upper module 1 U of FIGS. 12 and 13 at structural connection means 43 for structurally connecting, as shown in FIGS. 12 through 14 .
[0165] FIG. 14 shows a partial side view of the deployed configuration of the reflector module 1 R portion of an inflatable linear heliostatic concentrating solar module 1 A that is a solar photovoltaic module 1 . The solar photovoltaic module 1 has a reflection and concentration surface 7 includes at least one of (i) a reflective membrane 7 R which is reflective on its upper side and wherein an upwardly concave desired shape 7 S of said reflective membrane 7 R is at least in part maintained by the application of differential inflation pressure between said upper inflatable volume 9 and said lower inflatable volume 12 , (ii) a mirror element 7 M which is reflective and concave on its upper side 7 U, and (iii) a frame supported reflective membrane 7 FR (shown) which is supported by a frame 7 F and is reflective and concave on its upper side 7 U, wherein said frame 7 F comprises at least one of (a) perimeter structural members 50 P (shown) supporting said reflection and concentration surface 7 along at least portions of the perimeter of said reflection and concentration surface 7 , which perimeter structural members 50 P also contribute to perimeter restraint of at least one of said substantially transparent surface 11 and said bottom surface 13 ; (b) shaping means 50 S (shown) adjacent to said reflection and concentration surface 7 serving as shaping means for contributing to an upwardly concave desired shape 7 S of said reflection and concentration surface 7 ; and (c) frame supported damping means 50 FD (shown) adjacent to said reflection and concentration surface 7 serving as damping means 50 D (shown) for damping undesirable motion of said reflection and concentration surface 7 .
[0166] The reflection and concentration surface 7 is protected from the weather and from external physical or pressure induced disturbances by the elongated upper inflatable volume 9 and the elongated lower inflatable volume 12 . There is a substantially transparent surface 11 above the upper inflatable volume 9 , and a bottom surface 13 below the lower inflated volume 12 .
[0167] The embodiment of FIG. 14 shows the solar photovoltaic module 1 , wherein said elongated upper inflatable volume 9 includes an inflatable central portion 47 with an approximately constant cross-section on planar cuts perpendicular to the axis of elongation of said elongated upper inflatable volume 9 , and further includes left and right end closure portions 48 on the left and right sides of said inflatable central portion 47 , which left and right closure portions 48 serve to provide left and right side enclosure for said elongated upper inflatable volume 9 , wherein said left and right end closure portions 48 are at least one of (a) transparent, (b) partially transparent, (c) reflective, (d) partially reflective and (e) nontransparent; and wherein said left and right end closure portions 48 comprise at least one of (i) a membrane 48 M, (ii) an at least partially framed membrane 48 F (shown), (iii) an at least partially rigid dome segment 48 R, (iv) a plate member 48 P (shown), and (v) a dished plate member 48 D.
[0168] Features of the illustrated left and right closure portions 48 can be better understood with reference to the legends shown on the right closure portion that also apply equally to the left closure portion. Upward and downward projecting (transparent) plate members 48 P are hingedly attached by hinges 39 to the top and bottom respectively of the right end portion of the frame 7 F, that is also the right end portion of the perimeter structural members 50 P. The plate members 48 P are preferably centrally located on, and less than the full width of the right end portion of the perimeter structural members 50 P. When the upper inflatable volume 9 and lower inflatable volume 12 are inflated, as illustrated, the four plate members 48 P will be pressed outwards up to when the plate stop members 48 PS butt against the beam members 46 B of the upper module 1 U, as shown in FIG. 12 (but not shown here in FIG. 14 ).
[0169] The at least partially framed membranes 48 F extend from the sides of the upward projecting plate member 48 P and are preferably attached (e.g., bonded and/or fastened & sealed) on their inner sides to the plate member 48 P, on their upper end to a plate cap rim member 48 PC that is at the top of the plate member 48 P, on their outer sides to the right edges of the substantially transparent surface 11 , and on their bottom sides to the right end portion of the perimeter structural members 50 P. In this manner the upper right end closure portion 48 encloses the right end of the upper inflatable volume 9 and prevents pressurized air from leaking out.
[0170] Similarly, the at least partially framed membranes 48 F extend from the sides of the downward projecting plate member 48 P and are preferably attached (e.g., bonded and/or fastened & sealed) on their inner sides to the plate member 48 P, on their lower end to a plate cap rim member 48 PC that is at the bottom of the plate member 48 P, on their outer sides to the right edges of the bottom surface 13 , and on their top sides to the right end portion of the perimeter structural members 50 P. In this manner the lower right end closure portion 48 encloses the right end of the lower inflatable volume 12 and prevents pressurized air from leaking out.
[0171] The upper and lower left end closure portions 48 similarly enclose the left ends of the upper inflatable volume 9 and lower inflatable volume 12 respectively.
[0172] It will be understood that various closure portion engineering design and construction solutions are feasible to perform similar inflatable volume end closure, within the spirit and scope of the invention as claimed.
[0173] FIG. 15 shows a partial side view of a compact shipping configuration of the embodiment of FIG. 14 , being the shipping configuration of the reflector module 1 R portion of an inflatable linear heliostatic concentrating solar module 1 A that is a solar photovoltaic module 1 . Both the upper and lower plate members 48 P are rotated or folded inwards around the hinges 39 , on both the right and left sides of the reflector module 1 R, as illustrated. The flexible membranes of the substantially transparent surface 11 (not shown for clarity) and bottom surface 13 (not shown for clarity) are folded and packed down to within the space envelope defined by the folded plate members 48 P, in a manner known from the art of compact packing of flexible membranes using appropriate membrane folding patterns and geometries. Of course the upper inflatable volume 9 and lower inflatable volume 12 are substantially deflated in the compact shipping configuration of the reflector module 1 R, using means such as valve means or deflation valve means (not shown).
[0174] FIG. 15 thus shows compact shipping means 42 for shipping said solar photovoltaic module 1 in a reduced volume configuration in a shipping container 25 (to be shown in FIGS. 17 and 18 following), which compact shipping means 42 comprises at least one of (a) disconnectable connecting means 85 D (shown, being the structural connection means 43 ) providing means for easy disconnection of the upper module 1 U and the reflector module 1 R and the lower module 1 L for more compact shipping; (b) folding means 86 (shown, being the hinges 39 ) in at least one of the upper module 1 U and the reflector module 1 R (shown) and the lower module 1 L for folding constituent members for more compact shipping; and (c) provision of deflation means 76 M (shown) for deflating the substantially enclosed elongated inflatable volume 10 for more compact shipping.
[0175] FIGS. 16A and 16B show partial side views of deployed and shipping configurations of a lower module 1 L of an inflatable linear heliostatic concentrating solar module 1 A that is a solar photovoltaic module 1 , similar to that shown and described in detail earlier in the context of FIG. 1A . The lower module 1 L shown in FIG. 16A is attachable to the upper module 1 U via the axle members 46 A of the upper module 1 U, and is attachable through the upper module 1 U to the reflector module 1 R at structural connection means 43 for structurally connecting, as shown in FIGS. 12 through 16A inclusive.
[0176] FIG. 16A shows a partial side view of the deployed configuration of a lower module 1 L of an inflatable linear heliostatic concentrating solar module 1 A that is a solar photovoltaic module 1 , similar to that shown and described in detail earlier in the context of FIG. 1A . The frame tilting structure 74 and belt 63 B from FIG. 1A are not shown in the lower module 1 L, but can be readily attached when the solar photovoltaic module 1 is assembled by assembling together the lower module 1 L, the upper module 1 U (with ballast beam 58 B) and the reflector module 1 R along with the aforementioned frame tilting structure 74 and belt 63 B, in a manner similar to the embodiment shown and described in detail with reference to FIG. 1A .
[0177] FIG. 16B shows a partial side view of the compact shipping configuration of the lower module 1 L of FIG. 16A , with the upper “A frame” type tubular frame elements 73 TU folded inward and down around hinges 39 , as shown.
[0178] FIG. 16B thus shows compact shipping means 42 for shipping said solar photovoltaic module 1 in a reduced volume configuration in a shipping container 25 (to be shown in FIGS. 17 and 18 following), which compact shipping means 42 comprises at least one of (a) disconnectable connecting means 85 D (bearings 53 B) providing means for easy disconnection of the upper module 1 U and the reflector module 1 R and the lower module 1 L (shown) for more compact shipping; (b) folding means 86 (shown, being the hinges 39 ) in at least one of the upper module 1 U and the reflector module 1 R and the lower module 1 L (shown) for folding constituent members for more compact shipping; and (c) provision of deflation means 76 M (not applicable for lower module 1 L) for deflating the substantially enclosed elongated inflatable volume 10 for more compact shipping.
[0179] FIG. 17 and FIG. 18 show side sectional views of 40 foot and 20 foot representative scale solar modules, disassembled and packed into a representative shipping container.
[0180] FIG. 17 shows a side sectional view of a representative standard 45 foot hi-cube intermodal freight shipping container 25 , with representative exterior dimensions of 45′ 0″×8′ 0″×9′ 6″ and representative interior dimensions of 44′ 4″×7′ 8.59375″×8′ 9.9375″. In this side sectional view the interior length is 44′ 4″ and the interior height is 8′ 9.9375″. For representative but not limiting scale, a 10 foot ruler segment 100 is also shown. Two disassembled solar modules with 40 foot long solar receivers (e.g., elongated solar photovoltaic receivers 2 ) are shown packed into the 45 foot hi-cube intermodal freight shipping container. Without limitation, a representative solar photovoltaic module with a 40 ft long solar receiver, about 10 inches wide with dual row solar cells, and about 25 square meters of reflective area, would produce about 4 kilowatts of power with 16% efficient solar cells (and more power with more efficient concentrating solar cells that work at around 8 suns concentration). FIG. 17 shows packed within the standard 45 foot hi-cube intermodal freight shipping container 25 , the following items:
[0000] 2 upper modules 1 U including elongated solar photovoltaic receivers 2 ;
2 reflector modules 1 R;
2 lower modules 1 L;
2 frame tilting structures 74 , each split in halves for shipping; and
2 ballast beams (shown in dashed lines behind the lower modules 1 L in this view).
[0181] Other miscellaneous items for the 2 disassembled solar modules, such as 2 belt 63 B for the heliostatic control drive train, for example, can be suitably packed into available remaining volume in the shipping container 25 .
[0182] FIG. 18 shows a side sectional view of a representative standard 45 foot hi-cube intermodal freight shipping container 25 , with representative exterior dimensions of 45′ 0″×8′ 0″×9′ 6″ and representative interior dimensions of 44′ 4″×7′ 8.59375″×8′ 9.9375″. In this side sectional view the interior length is 44′ 4″ and the interior height is 8′ 9.9375″. For representative but not limiting scale, a 10 foot ruler segment 100 is also shown. Sixteen disassembled solar modules with 20 foot long solar receivers (e.g., elongated solar photovoltaic receivers 2 ) are shown packed into the 45 foot hi-cube intermodal freight shipping container, with eight visible in the view and another eight behind these. Without limitation, a representative solar photovoltaic module with a 20 ft long solar receiver, about 5 inches wide with a single row of solar cells, and about 6.25 square meters of reflective area, would produce about 1 kilowatt of power with 16% efficient solar cells (and more power with more efficient concentrating solar cells that work at around 8 suns concentration). FIG. 18 shows packed within the standard 45 foot hi-cube intermodal freight shipping container 25 , the following item totals (including hidden back items):
[0000] 16 upper modules 1 U including elongated solar photovoltaic receivers 2 ;
16 reflector modules 1 R;
16 lower modules 1 L;
16 frame tilting structures 74 (not necessary to split in half at this scale); and
16 ballast beams (shown in dashed lines behind each of the lower modules 1 L).
[0183] Other miscellaneous items for the 16 disassembled solar modules, such as 16 belt 63 B for the heliostatic control drive train, for example, can be suitably packed into available remaining volume in the shipping container 25 .
[0184] It should be understood that while FIGS. 17 and 18 show some specific compact shipping configurations for submodules of modular solar modules to be cost-effectively shipped in one specific high cube standard intermodal shipping container, many variant device sizes, modular disassembly involving folding elements and at least some deflation of inflatable members, and geometrically preferred or optimized packaging means in containers of varying sizes and shapes, are also possible within the spirit and scope of the invention.
[0185] FIGS. 12 through 18 collectively therefore shows solar photovoltaic modules 1 , wherein each said solar photovoltaic module 1 comprises plural connected constituent modules 1 C comprising:
[0000] (i) an upper module 1 U including an elongated solar photovoltaic receiver 2 ,
(ii) a reflector module 1 R including the reflection and concentration surface 7 and the substantially transparent surface 11 above said upper inflatable volume 10 U and the bottom surface 13 below said lower volume 14 , and
(iii) a lower module 1 L including said support structure 15 ;
and further comprising compact shipping means 42 for shipping said solar photovoltaic module 1 in a reduced volume configuration in a shipping container 25 , which compact shipping means 42 comprises at least one of (a) disconnectable connecting means 85 D providing means for easy disconnection of the upper module 1 U and the reflector module 1 R and the lower module 1 L for more compact shipping; (b) folding means 86 in at least one of the upper module 1 U and the reflector module 1 R and the lower module 1 L for folding constituent members for more compact shipping; and (c) provision of deflation means 76 M for deflating the substantially enclosed elongated inflatable volume 10 for more compact shipping.
[0186] FIG. 19 shows a partial end view of an embodiment similar to the embodiment of FIG. 1B (and FIG. 1A ) from the left end, at approximately the scale of FIG. 1B .
[0187] The illustrated left end structure 45 L portion of the left and right end structures 45 shown in FIG. 19 , is similar to the right end structure 45 R portion of the left and right end structures 45 shown in FIG. 11D . A beam member 46 B is shown in a substantially vertical orientation when the solar module is operational at solar noon (e.g., an orientation similar to that shown in FIGS. 1A and 1B ), and further comprises a second beam member 46 SB that is shown in a substantially horizontal orientation (substantially perpendicular to and integral with or attached to the beam member 46 B). The second beam member 46 SB is preferably designed to attach or mate with the left end member of the frame 7 F that surrounds the reflection and concentration surface 7 , at an interface that serves as structural connection means 43 . The use of crossed beams for the end structures 45 is similar to the embodiment illustrated in FIG. 11D .
[0188] The embodiment of FIG. 19 shows a motor 61 M that is a stepper motor 61 S, that drives a chain 63 H as actuation means for the heliostatic control means 18 to actuate rotation of the rotatable portion 19 of said solar photovoltaic module 1 to a commanded desired orientation. The embodiment of FIG. 19 also shows sensors 65 , which is at least one of sensors from the set of a Sun angle sensor, a light sensor, a temperature sensor, a wind sensor, an adverse weather sensor, an adverse condition sensor, a precipitation sensor, a time sensor, a power sensor, an energy sensor, a voltage sensor, a current sensor, a maintenance sensor, a failure sensor, a diagnostic sensor, a fluid flow sensor, a position sensor, an angle sensor, and a digital or count sensor. The embodiment of FIG. 19 also shows a computer 68 C which may comprise a microprocessor, digital computer, calculator or analog computer. The computer 68 C serves as at least one of (i) user input computer means for receiving and executing a user input instruction, (ii) sensor input computer means for receiving and processing an input signal from a sensor 65 , (iii) aiming computer means for algorithmically computing and commanding desired orientation of said rotatable portion 19 of said solar photovoltaic module 1 , (iv) stow computer means for computing and commanding a protective stow position of said rotatable portion 19 of said solar photovoltaic module 1 , and (v) diagnostic computer means for identifying at least one of nonoptimal operation, faulty operation and a failure condition of said solar photovoltaic module 1 .
[0189] FIG. 19 also illustrates lift element engagement means 49 (such as the illustrated hole in structure or other means known in the art) for engaging an element of a lift such as a forklift, a high lift, a crane, a jack, or other lift device, mechanism or machine for lifting all or part of the solar module 1 A, for installation, relocation, adjustment, maintenance or repair, for example. This feature will be particularly useful for installation of solar modules 1 A on the roof of a house or building.
[0190] FIG. 20 shows a plan view of a floating embodiment with a connected array 17 of plural inflatable linear heliostatic concentrating solar modules 1 A.
[0191] More specifically, FIG. 20 illustrates a connected array 17 of plural inflatable linear heliostatic concentrating solar modules 1 A including at least one inflatable linear cooled heliostatic concentrating solar photovoltaic module 1 , wherein:
[0000] each said solar module 1 A comprises an elongated solar receiver 2 A including a portion of substantially linear geometry 3 with a linear axis 4 ;
each said solar module 1 A comprises a reflection and concentration surface 7 for reflecting and concentrating sunrays 8 ;
each said solar module 1 A comprises a substantially enclosed elongated inflatable volume 10 comprising (i) an upper inflatable volume 10 U above said reflection and concentrating surface 7 , with a substantially transparent surface 11 above said upper inflatable volume 10 U, and further comprising (ii) a lower volume 14 (hidden and not visible in this view) below said reflection and concentrating surface 7 , with a bottom surface 13 (hidden and not visible in this view) below said lower volume 14 ;
each said solar photovoltaic module 1 includes cooling means 21 for removing excess heat 27 from its elongated solar receiver 2 A comprising an elongated solar photovoltaic receiver 2 , said cooling means 21 including a heated cooling fluid 26 that is heated by heat 27 from said elongated photovoltaic receiver 2 ;
further comprising connecting means 85 for connecting said plural inflatable linear heliostatic concentrating solar modules 1 A comprising at least one of (i) structural connecting means 85 S (shown) for structurally connecting a first solar photovoltaic module 1 F to a second solar module 1 S and (ii) heated fluid connecting means 85 F (not shown and not present in this embodiment) for conveying heat energy in heated cooling fluid 26 outflow from a first solar photovoltaic module 1 F to a heated fluid stream 26 S inflow into a second solar module 1 S wherein the heated fluid stream 26 S is further heated by concentrated radiation energy received from the reflection and concentration surface 7 for reflecting and concentrating sunrays 8 in the second solar module 1 S;
further comprising support structure 15 for supporting said plural inflatable linear heliostatic concentrating solar modules 1 A on a supporting surface 16 ;
further comprising heliostatic control means 18 for aiming at least one rotatable portion 19 of said connected array 17 of plural inflatable linear heliostatic concentrating solar modules 1 A, as a function of at least one of time and other parameters, such that incoming sunrays 8 from a sunward direction 8 D will be reflected and concentrated by said reflection and concentration surfaces 7 , onto said elongated solar receivers 2 A at a concentration ratio of at least two suns; and
further comprising electrical power means 20 for collecting and transmitting electrical power from said elongated solar photovoltaic receiver 2 .
[0192] Floating support structure 15 F is shown, which serves both a structures purpose and a buoyancy purpose. An example of floating support structure 15 F entails the use of sealed hollow structural members such as pipe section material. The cooling means 21 for removing excess heat 27 can optionally use air cooling means or liquid cooling means, as described in detail with reference to earlier described embodiments of the invention. Air cooling means can use fan powered cooling air flow in a air cooling pipe 22 A (not shown). Liquid cooling means (shown) can use a pump 30 to pump cooling liquid in cooling fluid flow direction 21 F in tubes and/or chambers adjacent to the elongated solar photovoltaic receivers 2 so as to keep the solar cells therein at low risk of heat damage and high photovoltaic conversion efficiency. A closed loop liquid cooling system is shown, wherein a pump 30 pumps cooling liquid through the cooling means 21 , and then return flow of heated cooling fluid runs through underwater spiral tube heat transfer means 32 ST where heat is dumped into the water under the water surface 16 W.
[0193] FIG. 20 also illustrates a connected array 17 of plural inflatable linear heliostatic concentrating solar modules 1 A of claim 3 , wherein said supporting surface 16 comprises a water surface 16 W above an underwater ground surface 16 UG, wherein said connected array 17 of plural inflatable linear heliostatic concentrating solar modules 1 A comprises a floating connected array 17 F supported at least in part by a buoyancy force 16 B;
[0000] wherein said heliostatic control means 18 comprises at least one of
(i) (not shown) azimuth heliostatic control means 18 A for rotating said floating connected array 17 F on said water surface 16 W to substantially follow the azimuth angle 8 A (not visible in this view with vertical downward sunrays 8 illustrated, corresponding to a solar noon azimuth) of the incoming sunrays 8 over a period of solar time with the linear axis 1 AL of each said solar module 1 A aligned substantially parallel with said azimuth angle 8 A of the incoming sunrays; and
(ii) (shown) a combination of (a) azimuth heliostatic control means 18 A for rotating said floating connected array 17 F on said water surface 16 W to substantially follow the azimuth angle 8 A (not visible in this view with vertical downward sunrays 8 illustrated, corresponding to a solar noon azimuth) of the incoming sunrays 8 over a period of solar time with the linear axis 1 AL of each said solar module 1 A aligned substantially perpendicular to said azimuth angle 8 A of the incoming sunrays, and (b) elevation heliostatic control means 18 E (not visible in this view with vertical downward sunrays 8 illustrated, corresponding to a 90 degree elevation angle) for controlling the elevation orientation of rotatable portions 19 of said plural inflatable linear heliostatic concentrating solar modules 1 A including said reflection and concentration surfaces 7 and said solar receivers 2 A, to substantially follow the elevation angle 8 E of the incoming sunrays 8 over a period of solar time.
[0194] Thus the embodiment of FIG. 20 has two axis heliostatic tracking of the Sun's apparent motion in azimuth and elevation, resulting in maximum solar power harvest.
[0195] The embodiment of FIG. 20 can be built at any arbitrary size scale. Some examples include solar modules 1 A with elongated solar receivers 2 A that are about 21 feet long, so two disassembled solar modules 1 A can fit end on end in a 45 foot long high cube container; solar modules 1 A with elongated solar receivers 2 A that are about 42 feet long, so one disassembled solar module 1 A can fit lengthwise in a 45 foot long high cube container, and other scales from small to gigantic.
[0196] FIG. 20 also illustrates a connected array 17 of plural inflatable linear heliostatic concentrating solar modules 1 A of claim 22 , wherein said floating connected array 17 F can be held in a desired position envelope 17 PE by position holding means 17 PH for holding said floating connected array 17 F in said desired position envelope 17 PE, which position holding means 17 PH includes anchor means 17 A for anchoring members 17 M in said underwater ground surface 16 UG, and underwater link means 17 UL comprising at least one of underwater tethers 15 T, cables, rods, posts, beams, trusses and plates for linking the underwater anchor means to at least one positioning float 17 F; and wherein said azimuth heliostatic control means 18 A includes powered control means 17 PC for azimuthally rotating said floating connected array 17 F relative to at least one positioning float 17 F.
[0197] Note that the illustrated embodiment has a single central positioning float 17 F, while variant embodiments may have plural positioning floats 17 F around the periphery of the connected array 17 , such as connected to the illustrated wave breaking means 16 WB. Note also that the underwater link means 17 UL such as the underwater tethers 15 T can also be beneficially used to tow the floating solar module to an installation site (e.g., being pulled by a tugboat of some sort), where it is subsequently tethered.
[0198] FIG. 20 also illustrates a connected array 17 of plural inflatable linear heliostatic concentrating solar modules 1 A of claim 22 , further comprising wave breaking means 16 WB located at least in part along a perimeter location 16 PL on the periphery around said floating connected array 17 F, which wave breaking means 16 WB serves as means for at least one of blocking and reducing the magnitude of incoming waves 16 WA on the water surface 16 W that approach said floating connected array 17 F from outside the vicinity of said floating connected array 17 F.
[0199] Note that a variety of wave breaking means 16 WB may be used, including rigid or semirigid walls, perforated or mesh walls, inflated ring or tube or sphere elements, shaped hulls, flow deflection vanes or foils, etc.
[0200] FIG. 21 shows a plan view of a floating embodiment with a connected array 17 of plural inflatable linear heliostatic concentrating solar modules 1 A, similar to FIG. 20 but with one axis heliostatic tracking. The only heliostatic tracking provided is azimuth tracking, with azimuth heliostatic control means 18 A for rotating said floating connected array 17 F on said water surface 16 W to substantially follow the azimuth angle 8 A (not visible in this view with vertical downward sunrays 8 illustrated, corresponding to a solar noon azimuth) of the incoming sunrays 8 over a period of solar time with the linear axis 1 AL of each said solar module 1 A aligned substantially parallel (NOT perpendicular as for the embodiment of FIG. 20 ) with said azimuth angle 8 A of the incoming sunrays.
[0201] Note that in FIG. 21 no elevation heliostatic control means 18 E exist to substantially follow the elevation angle 8 E of the incoming sunrays 8 over a period of solar time; and there are no rotatable portions 19 of the solar module 1 A that rotate in elevation angle. Since the azimuth control aligns parallel rather than perpendicular to the linear axis 1 AL of each said solar module 1 A, it is possible for the embodiment of FIG. 21 to have solar modules located close to each other without shadowing losses, and this enables the connected array 17 of the embodiment of FIG. 21 to have 4 rather than 2 solar modules 1 A, as illustrated.
[0202] FIG. 21 thus illustrates a connected array 17 of plural inflatable linear heliostatic concentrating solar modules 1 A of claim 3 , wherein said supporting surface 16 comprises a water surface 16 W above an underwater ground surface 16 UG, wherein said connected array 17 of plural inflatable linear heliostatic concentrating solar modules 1 A comprises a floating connected array 17 F supported at least in part by a buoyancy force 16 B;
[0000] wherein said heliostatic control means 18 comprises at least one of
(i) (shown) azimuth heliostatic control means 18 A for rotating said floating connected array 17 F on said water surface 16 W to substantially follow the azimuth angle 8 A (not visible in this view with vertical downward sunrays 8 illustrated, corresponding to a solar noon azimuth) of the incoming sunrays 8 over a period of solar time with the linear axis 1 AL of each said solar module 1 A aligned substantially parallel with said azimuth angle 8 A of the incoming sunrays; and
(ii) (not shown) a combination of (a) azimuth heliostatic control means 18 A for rotating said floating connected array 17 F on said water surface 16 W to substantially follow the azimuth angle 8 A (not visible in this view with vertical downward sunrays 8 illustrated, corresponding to a solar noon azimuth) of the incoming sunrays 8 over a period of solar time with the linear axis 1 AL of each said solar module 1 A aligned substantially perpendicular to said azimuth angle 8 A of the incoming sunrays, and (b) elevation heliostatic control means 18 E (not visible in this view with vertical downward sunrays 8 illustrated, corresponding to a 90 degree elevation angle) for controlling the elevation orientation of rotatable portions 19 of said plural inflatable linear heliostatic concentrating solar modules 1 A including said reflection and concentration surfaces 7 and said solar receivers 2 A, to substantially follow the elevation angle 8 E of the incoming sunrays 8 over a period of solar time.
[0203] FIG. 22A shows a plan view of a floating embodiment with some of the features of the embodiment of FIG. 20 , but with a combination of solar modules 1 A, similar to the embodiment of FIG. 6A . Reference numerals for features shown in FIG. 22A correspond to the same reference numerals as described in detail with respect to FIGS. 20 and 6A preceding. FIG. 22A shows two types of solar modules 1 A in sequence, where the modules on the left and right of the Figure are solar photovoltaic modules 1 that are first solar photovoltaic modules 1 F; while the modules in the center of the Figure are solar thermal modules 1 T that are second solar modules 1 S. The relationship and functioning of the different solar modules 1 A in sequence are similar to the case described in detail with regard to FIG. 6A . A total of 10 solar modules 1 A are shown in this floating embodiment, with two-axis heliostatic tracking similar to the embodiment of FIG. 20 .
[0204] FIG. 22B shows a plan view of a floating embodiment with similar features to that of FIG. 22A , but with a combination of solar modules 1 A, similar to the embodiment of FIG. 6B . Reference numerals for features shown in FIG. 22B correspond to the same reference numerals as described in detail with respect to FIGS. 20 and 6B preceding. FIG. 22B shows three types of solar modules 1 A in sequence, where the first in sequence are solar photovoltaic modules 1 that are first solar photovoltaic modules 1 F (2 rightmost modules and 2 leftmost modules in the view shown); while the second in sequence modules comprise second solar modules 15 that are solar thermal modules 1 T combined with a higher temperature solar photovoltaic modules 1 H with higher temperature elongated solar photovoltaic receivers 2 H (4 modules that are 3rd from right and 3rd from left in the view shown); and the last in sequence in the string of connected modules comprising downstream solar modules 1 D (2 center modules, or 4th from either left or right in the view shown) that in this case are also solar thermal modules 1 T that are intended to operate at a still higher solar receiver temperature than the second solar modules 1 S. Note that the higher temperature solar photovoltaic modules 1 H in FIG. 22B include higher temperature solar photovoltaic receivers 99 .
[0205] FIG. 22B also shows a tethered barge 17 TB attached to or integral with a positioning float 17 PF, which tethered barge 17 TB also carries the thermodynamic cycle engine 78 E and other members described in detail earlier in the context of FIG. 6B . Note that alternate locations for all modules and members at various locations in the floating connected array 17 F, are also of course possible within the spirit and scope of the invention as claimed.
[0206] FIG. 22C shows a plan view of an embodiment of a floating connected array 17 F similar in many aspects to the embodiments of FIGS. 22A and 22B , but with more inflatable linear heliostatic concentrating solar modules 1 A, numbering 18. Some features illustrated in this embodiment include use of different length solar modules 1 A to more effectively utilize the available plan view area for solar collection; a central platform location for a thermodynamic cycle engine 78 E; the use of six positioning floats 17 PF for more precise and fault-tolerant position holding of the floating connected array 17 F in the presence of water currents and wind; and the optional use of heliostatic control means 18 wherein the linear axis 1 AL of the solar modules 1 A aligns with the solar azimuth angle for very low Sun elevation angles at times close to sunrise and sunset, to minimize shadowing losses, while the linear axis 1 AL of the solar modules 1 A is rotated to align perpendicular to the solar azimuth angle for most of the day, where shadowing losses are small or nonexistent, and two axis tracking using both azimuth heliostatic control means 18 A and elevation heliostatic control means 18 E effectively places the plane of each reflection and concentration surface 7 perpendicular or normal to the incident sunrays 8 .
[0207] FIG. 22D shows multiple floating connected arrays 17 F of the type shown in FIG. 22C , arranged in a pattern on the water surface 16 W above the underwater ground surface 16 UG, that includes a triangular pattern as shown. It will be understood that with shared anchor means 17 A connected by position holding means 17 PH (such as underwater tethers) to multiple proximal floating connected arrays 17 F, alternate geometric arrangements such as space filling triangular, space filling square, space filling rectangular, space filling hexagonal, and other space filling or non space filling two dimensional geometric arrangements, are possible within the spirit and scope of the invention.
[0208] FIG. 22E shows a plan view of an embodiment of a floating connected array 17 F similar in many aspects to the embodiments of FIGS. 22A , 22 B and 22 C, but with more inflatable linear heliostatic concentrating solar modules 1 A, numbering 152 but number not limiting. The scale of this embodiment will typically but not necessarily be larger than the scale of the embodiments of FIGS. 22A , 22 B and 22 C. Representative diameters of the floating connected array 17 F may range from 20 meters to 20,000 meters, without limitation.
[0209] FIG. 22F shows a plan view of the embodiment of a connected array 17 of plural inflatable linear heliostatic concentrating solar modules 1 A illustrated in FIG. 22E , but now further comprising offshore wind and water current renewable energy harvesting subsystems substantially surrounding and connected to the connected array 17 that is a floating connected array 17 F. The illustrated wind and water current renewable energy harvesting subsystems are of a class previously described in U.S. patent application Ser. No. 11/986,240 entitled “Fluid-Dynamic Renewable Energy Harvesting System.”
[0210] FIG. 22F shows the connected array 17 that is a floating connected array 17 F, held in place by perimeter positioning floats 17 PF connected to tethered barges 17 TB, that are held in place relative to the underwater ground surface 16 UG by position holding means 17 PH such as underwater tethers that are anchored in the underwater ground surface 16 UG by anchor means 17 A. Features described earlier in the context of FIG. 20 and FIG. 22C also apply to this embodiment of a connected array 17 of plural inflatable linear heliostatic concentrating solar modules 1 A. The connected array 17 of plural inflatable linear heliostatic concentrating solar modules 1 A harvests solar renewable energy using photovoltaic means supplemented in some preferred embodiments by solar thermal energy harvesting means.
[0211] The same tethered barges 17 TB that hold the floating connected array 17 F (for collecting solar energy) in place, also hold in place (i) a water current energy harvesting system 87 C with plural hydrofoils 87 H connected by a hydrofoil connecting structure 87 HC that is a ring shaped structure in the illustrated embodiment, and (ii) a wind energy harvesting system 87 W with plural airfoils 87 AF connected by an airfoil connecting structure 87 AC that comprises two concentric ring structures in the illustrated embodiment. Note for illustration clarity, only a few of the plural hydrofoils 87 H that are connected all around the ring shaped hydrofoil connecting structure 87 HC are shown in the Figure. The angles of attack of the airfoils 87 AF and hydrofoils 87 H are intended to be controllable as these fluid foils move along substantially circular paths, to optimize energy extraction from the wind and water current vector fields present at any given time. For the illustrated wind direction 87 AD (assumed uniform vector field for illustrative purposes) and the illustrated water current direction 87 HD (assumed uniform vector field for illustrative purposes), the illustrated angles of attack will cause both the airfoil connecting structure 87 AC and the hydrofoil connecting structure 87 HC to rotate clockwise in the illustrated view, with mechanical energy then convertible to electrical energy by generator means 80 at the interface between these connecting structures and the structural connections with the tethered barges 17 TB. These generator means 80 are over and above the generator means 80 associated with the thermodynamic cycle engine 78 E associated with the connected array 17 of plural inflatable linear heliostatic concentrating solar modules 1 A. Electrical power from the various generator means 80 as well as the solar cells of the solar photovoltaic modules 1 can be consolidated and conditioned at electric power conditioning means 80 C, optionally stored in electric energy storage means 80 S (e.g., a variety of means such as battery means, electrolysis plus fuel cell means, thermal storage means, mechanical storage means such as flywheel means, supercapacitor means, etc.), and transmitted by electric power transmission means 80 T such as underwater power transmission cables leading to utility or commercial or private customers or users. The electric power transmission means 80 T may comprise superconducting cables, high to ultra high voltage AC cables, high to ultra high voltage DC cables, and other transmission means known from the state-of-the-art.
[0212] It will be understood that in variant embodiments of the embodiment of FIG. 22F , water current and wind energy harvesting systems may not both be provided, but only one or the other. Representative diameters of the floating connected array 17 F may range from 20 meters to 20,000 meters, without limitation. As illustrated, these would correspond with solar module 1 A lengths ranging from about 1.9 to 1900 meters, chords of airfoils 87 AF ranging from about 0.9 to 900 meters, and chords of hydrofoils 87 H ranging from about 0.25 meter to 250 meters. While airfoil and hydrofoil heights (or spans, out of the page and into the page in the plan view of FIG. 22F ) may vary considerably for aspect ratios ranging from 2 to 40, as is known from the art of airfoil and hydrofoil wing design, for representative and not limiting aspect ratios of 5 and some typical taper ratios, the corresponding ranges of airfoils 87 AF heights would range approximately from 3 to 3,000 meters, while the corresponding range of hydrofoil 87 H heights (or depths under the water surface 16 W) would range approximately from 1 meter to 1000 meters. It will also be understood that varying scales of devices such as solar modules 1 A, airfoils 87 AF and hydrofoils 87 H, can be mixed and matched in embodiments of this class, within the spirit and scope of the invention.
[0213] In addition to the illustrated wind energy harvesting subsystem and ocean current/tidal current energy harvesting subsystem that are connected with the connected array 17 of plural inflatable linear heliostatic concentrating solar modules 1 A, FIG. 22F further illustrates a connected ocean thermal energy harvesting system 87 T that includes deep cold water inlet means 87 DC for intaking deep cold water for use at the low temperature part of a thermodynamic cycle engine 78 E, which may be the same and/or different from a thermodynamic cycle engine 78 E using heat energy collected by at least some of the plural inflatable linear heliostatic concentrating solar modules 1 A. Where different, the high temperature part of the Ocean Thermal Energy Conversion (OTEC) subsystem may use heat from warmer water collected from near-surface warm water inlet means 87 SW. Electrical power from the OTEC will also preferably connect with the aforementioned electric power conditioning means 80 C, electric energy storage means 80 S, and electric power transmission means 80 T.
[0214] FIG. 22F thus illustrates a connected array 17 of plural inflatable linear heliostatic concentrating solar modules 1 A, further comprising an additional renewable energy harvesting system 87 that is connected to said floating connected array 17 F, which additional renewable energy harvesting system 87 comprises at least one of (i) a wind energy harvesting system 87 W with airfoils 87 AF that revolve around said floating connected array 17 F, (ii) a water current energy harvesting system 87 C with hydrofoils 87 H that revolve around said floating connected array 17 F, and (iii) an ocean thermal energy harvesting system 87 T that includes deep cold water inlet means 87 DC for intaking deep cold water for use at the low temperature part of a thermodynamic cycle engine 78 E.
[0215] Note that the airfoils 87 AF may be airfoils, wings, semirigid airfoils, inflated or partially inflated airfoils, wire or strut braced airfoils, sails, and other airfoil types known in the art. Various airfoil planforms, spans, chords, aspect ratios, tapers, twist distributions, camber distributions and airfoil sections may similarly be used. Various airfoil structures may also be used. Similarly a wide variety of hydrofoils 87 H may also be used.
[0216] FIG. 22G shows a plan view of an embodiment of a floating connected array 17 F similar in many aspects to the embodiments of FIGS. 22A , 22 B, 22 C and 22 E, but with more inflatable linear heliostatic concentrating solar modules 1 A, numbering 1,920 but number not limiting. The scale of this embodiment will typically but not necessarily be larger than the scale of the embodiments of FIGS. 22A , 22 B, 22 C and 22 E. Representative diameters of the floating connected array 17 F may range from 50 meters to 50 kilometers, without limitation. Electrical power from the generator means 80 as well as the solar cells of the solar photovoltaic modules 1 can be consolidated and conditioned at electric power conditioning means 80 C, optionally stored in electric energy storage means 80 S (e.g., a variety of means such as battery means, electrolysis plus fuel cell means, thermal storage means, mechanical storage means such as flywheel means, supercapacitor means, etc.), and transmitted by electric power transmission means 80 T such as underwater power transmission cables leading to utility or commercial or private customers or users. The electric power transmission means 80 T may comprise superconducting cables, high to ultra high voltage AC cables, high to ultra high voltage DC cables, and other transmission means known from the state-of-the-art.
[0217] FIG. 23A shows a partial sectional view of the floating embodiment described earlier with reference to the plan view shown in FIG. 22A . Some features of the embodiment of FIG. 22A can be better understood from the partial sectional view shown in FIG. 23A . Note that the buoyancy force 16 B acts on support structure 15 that is floating support structure 15 F that uses plural tubular frame elements 73 TU with many watertight compartments (not visible in this view) so as to maintain buoyancy even in the event of damage or rupture of one watertight compartment. Note also that the illustrated wave breaking means 16 WB at the perimeter location 16 PL uses two spaced wall like members that may be continuous or have holes or slats or water flow deflection foils; and that the two spaced wall like members are shown connected by bracing wire and/or truss structure. Many alternate wave breaking means 16 WB using a variety of wave reflection and/or wave deflection and/or wave energy absorption elements, are possible within the spirit and scope of the invention.
[0218] FIG. 23B shows a partial sectional view of another floating embodiment, in which the buoyancy force 16 B acts directly on the inflatable linear heliostatic concentrating solar modules 1 A, with the water surface 16 W displaced by the bottom surfaces 13 .
[0219] FIG. 23C shows a partial sectional view of a floating embodiment similar in many ways to that described in FIG. 23A , with a few notable differences. One difference is the use of inflated perimeter rings combined with underwater skinned truss structure for the wave breaking means 16 WB, as illustrated. Another difference is the use of a support structure 15 that has portions significantly below the mean level of the water surface 16 W, to permit installation, removal and maintenance access using a shallow draught boat serving as a movable service support structure 15 S, as illustrated. The movable service support structure 15 S is shown in the process of transporting a replacement solar module 1 A between adjacent rows of installed solar modules 1 A. Lift or jack or crane means (not shown) may optionally be provided on the movable service support structure 15 S, for facilitating installation and de-installation of solar modules 1 A. In alternate embodiments a movable service support structure 15 S may utilize a wheel supported device (not shown) rather than a buoyancy supported device, with the wheels running on tracks or paved or fabricated support strips with edge guides.
[0220] FIG. 23D shows a partial sectional view of a floating embodiment in many ways similar to that of FIG. 23B , but different in having much more closely spaced solar modules 1 A that go with the type of floating solar energy harvesting system that has only azimuth heliostatic tracking with no elevation tracking, as described earlier in the context of the embodiment of FIG. 21 . FIG. 23D also illustrates the installation of a warning device 91 , such as a light or beacon or flag or sign, to warn people in vehicles (e.g, boats or ships or planes) from coming dangerously close to the floating solar energy harvesting system.
[0221] The various embodiments described above will preferably incorporate appropriate safety features, warning labels to keep eyes away from concentrated light, fingers and body parts away from high temperature areas, and features to minimize risk of inflatable explosion, among others.
[0222] While several preferred embodiments have been described in detail above with reference to the Figures, it should be understood that further variations and modifications are possible within the spirit and scope of the invention as claimed.
REFERENCES
[0000]
U.S. Pat. No. 5,404,868, “Apparatus Using a Balloon Supported Reflective Surface for Reflecting Light from the Sun”
U.S. patent application Ser. No. 11/651,396, “Inflatable Heliostatic Solar Power Collector”
U.S. patent application Ser. No. 11/986,240, “Fluid-Dynamic Renewable Energy Harvesting System” | Increased utilization of solar power is highly desirable as solar power is a readily available renewable resource with power potential far exceeding total global needs; and as solar power does not contribute to pollutants associated with fossil fuel power, such as unburned hydrocarbons, NOx and carbon dioxide. The present invention provides low-cost inflatable heliostatic solar power collectors, which a range of embodiments suitable for flexible utilization in small, medium, or utility scale applications. The inflatable heliostatic power collectors use a reflective surface or membrane “sandwiched” between two inflated chambers, and attached solar power receivers which are of concentrating photovoltaic and optionally also concentrating solar thermal types. Floating embodiments are described for certain beneficial applications on. Modest concentration ratios enable benefits in both reduced cost and increased conversion efficiency, relative to simple prior-art flat plate solar collectors. | 5 |
BACKGROUND OF THE INVENTION
[0001] The invention relates in general to the operation of a refrigeration system, and more specifically to the control of at least one electronic expansion valve coupled to an economizer in a refrigeration system.
[0002] Refrigeration systems generally include a refrigerant circuit including a compressor, a condenser, a main throttling device, and an evaporator. Vapor refrigerant is delivered to the compressor where the temperature and pressure of the vapor refrigerant is increased. The compressed vapor refrigerant is then delivered to the condenser where heat is removed from the vapor refrigerant in order to condense the vapor refrigerant into liquid form. The liquid refrigerant is then delivered from the condenser to a main throttling device, such as a mechanical thermostatic expansion valve. The main throttling device restricts the flow of the liquid refrigerant by forcing the liquid through a small orifice in order to decrease the pressure of the liquid and therefore decrease the boiling point of the liquid. Upon exiting the main throttling device, the liquid refrigerant is in the form of liquid refrigerant droplets. The liquid refrigerant droplets are delivered from the main throttling device to the evaporator, which is located within or in thermal communication with the space to be conditioned by the refrigeration system. As air passes over the evaporator, the liquid refrigerant droplets absorb heat from the air in order to cool the air. The cooled air is circulated through the conditioned space to cool the masses within the conditioned space. Once the liquid refrigerant droplets have absorbed sufficient heat, the liquid refrigerant droplets vaporize. To complete the refrigeration cycle, the vapor refrigerant is delivered from the evaporator back to the compressor.
[0003] An additional heat exchanger in the form of an economizer may be added to the refrigeration system in order to enhance the efficiency of the cycle. The economizer is often coupled between the condenser and the main throttling device. Specifically, the economizer is coupled to the condenser by an economizer input line having a first branch and a second branch. The first branch delivers refrigerant through the economizer to the main throttling device. The second branch delivers refrigerant through a secondary throttling device, through an economizer chamber within the economizer, and back to the compressor. In an economizer system, the refrigerant flowing to the main throttling device is routed through the economizer to be sub-cooled, while some refrigerant is drawn off through the second branch of the economizer input line to a secondary throttling device. The drawn-off refrigerant passes through the secondary throttling device, where it is cooled by the throttling process, and into the economizer chamber. Once in the economizer chamber, the drawn-off refrigerant is in a heat transfer relationship with the refrigerant flowing through the first branch of the economizer input line to the main throttling device. The drawn-off refrigerant absorbs heat from the refrigerant flowing through the first branch to the main throttling device. Thus, the refrigerant flowing through the first branch is sub-cooled. Liquid refrigerant is sub-cooled when the temperature of the liquid is lower than the vaporization temperature for the refrigerant at a given pressure. The drawn-off refrigerant absorbs heat until it vaporizes.
[0004] Before the drawn-off refrigerant is directed back to the compressor, the vaporized refrigerant has generally reached a superheat level. The refrigerant reaches a superheat level when all of the refrigerant has vaporized and the temperature of the refrigerant is above the vaporization temperature for the refrigerant at a given pressure. The refrigerant at the superheated level is then directed back to the compressor.
[0005] The operating conditions of the refrigeration system are controlled, in part, by the operation of the economizer. The economizer is controlled by the secondary throttling device. Generally, the main and secondary throttling devices are mechanical thermostatic expansion valves (TXV), which operate based on the temperature and pressure of the refrigerant passing through the valve.
SUMMARY OF THE INVENTION
[0006] The use of TXVs for the main and secondary throttling devices has several limitations. First, TXVs cannot be dynamically adjusted to control the operating conditions of the refrigeration system. TXVs are initially designed to optimize the operating conditions of the refrigeration system, but the TXVs cannot be dynamically adjusted to optimize the operating conditions at all times.
[0007] Moreover, TXVs can only accommodate one set of operating conditions. A TXV in the economizer cycle is generally designed to maintain one set of primary operating conditions. However, extraordinary or secondary operating conditions may occur, which may demand the primary operating conditions to be overridden. A TXV cannot accommodate secondary operating conditions that may be desired to periodically override the primary operating conditions.
[0008] Accordingly, the invention provides a method and apparatus for controlling at least one electronic expansion valve coupled to an economizer in a refrigeration system in order to dynamically control the refrigeration system operating conditions and in order to accommodate more than one set of operating conditions. The refrigeration system generally includes a compressor, a condenser coupled to the compressor, a heat exchanger coupled to both the condenser and the compressor, an evaporator coupled to both the heat exchanger and the compressor, and an electronic expansion valve, an input of the valve coupled between the condenser and the heat exchanger, an output of the valve coupled to the compressor.
[0009] The above-described structure is normally operated under a set of primary operating conditions. One condition is that the state of the refrigerant flowing from the heat exchanger to the compressor is maintained above superheat temperature. More specifically, the pressure between the heat exchanger and the compressor is sensed. The sensed pressure is converted into a saturation temperature value. The temperature between the heat exchanger and the compressor is sensed. The saturated suction temperature value is compared to the sensed temperature. The flow of refrigerant through the EXV is adjusted until the sensed temperature is greater than the saturated suction temperature value.
[0010] The above-described structure can also be used to control the capacity of the system. More specifically, the method can include determining the required capacity of the system and adjusting the flow of refrigerant through the electronic expansion valve to adjust the actual capacity of the system toward the required capacity of the system. For example, if the required capacity is less than the actual capacity, then the flow of refrigerant through the electronic expansion valve can be decreased. Likewise, if the required capacity is greater than the actual capacity, then the flow of refrigerant through the electronic expansion valve can be increased. In either event the method may require that the primary set of operating conditions be overridden.
[0011] In another aspect of the invention, the system is operated to maintain the power of the system below a threshold value (e.g., below a max rated horsepower). This method includes determining the power required to operate the compressor based on the measurement of system parameters; comparing the power required to a threshold value; and adjusting the flow of refrigerant through the electronic expansion valve in order to keep the power required below the threshold value. There are many different ways to determine the required power (e.g., by sensing the pressure between the heat exchanger and the compressor, the pressure between the evaporator and the compressor, the pressure between the compressor and the condenser, and the flow rate of refrigerant). In this embodiment, if the horsepower required to operate the compressor is less than the threshold value, then there is no need to adjust the flow of refrigerant through the electronic expansion valve. However, if the power required to operate the compressor is greater than the threshold value, then the flow of refrigerant through the electronic expansion valve can be decreased to avoid operating the system above its rated power limit. In order to do this, the primary operating conditions may need to be overridden.
[0012] In yet another aspect of the invention, the system is operated in order to prevent overheating of the compressor. More specifically, the flow of refrigerant from the heat exchanger to the compressor can be adjusted so that some amount of liquid refrigerant is provided to quench the compressor. The method includes measuring a system parameter corresponding with the temperature of the compressor; comparing the measured system parameter to a threshold value; and adjusting the flow of refrigerant into the compressor by adjusting the flow of refrigerant through the electronic expansion valve in order to keep the system parameter below the threshold value. The system parameter can be any parameter that corresponds with the temperature of the compressor (e.g., the temperature of the compressor, the temperature of refrigerant flowing from the compressor, etc.). In practice, if the system parameter exceeds the threshold value, the flow of refrigerant through the electronic expansion valve can be increased in order to provide a volume of liquid refrigerant to quench the compressor. In order to do this, the primary operating conditions may need to be overridden.
[0013] Other features and advantages of the invention will become apparent to those of ordinary skill in the art upon review of the following description, claims, and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] [0014]FIG. 1 is a schematic representation of a refrigeration system embodying the invention.
[0015] [0015]FIG. 2 illustrates a method of controlling the superheat level of the refrigerant in the refrigeration system of FIG. 1.
[0016] [0016]FIG. 3 illustrates a method of quenching the compressor of the refrigeration system of FIG. 1.
[0017] [0017]FIGS. 4A and 4B illustrate a method of controlling the horsepower of the engine of the refrigeration system of FIG. 1.
[0018] [0018]FIG. 5 illustrates the refrigeration system of FIG. 1 located within a refrigeration system-housing unit coupled to a transport container coupled to a tractor trailer.
[0019] Before one embodiment of the invention is explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced or being carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting.
DETAILED DESCRIPTION OF THE INVENTION
[0020] [0020]FIG. 1 illustrates a refrigeration system 10 embodying the invention. The refrigeration system 10 includes a refrigerant circuit 12 and a microprocessor circuit 100 . The refrigerant circuit 12 generally defines the flow of fluid refrigerant through the refrigeration system 10 . The refrigerant circuit 12 includes a first fluid path 14 and a second fluid path 40 .
[0021] The first fluid path 14 is defined by a compressor 16 , a discharge line 18 , a condenser 20 , an economizer input line 22 , an economizer 24 , a first economizer output line 26 , a main electronic expansion valve (EXV) 28 , an evaporator input line 30 , an evaporator 32 , and a suction line 34 . The compressor 16 is fluidly coupled to the condenser 20 by the discharge line 18 . The condenser 20 is fluidly coupled to the economizer 24 by the economizer input line 22 . The economizer input line 22 includes a first branch 22 a and a second branch 22 b . The first branch 22 a defines part of the first fluid path 14 , while the second branch 22 b defines part of the second fluid path 40 , as will be described below. The economizer 24 is fluidly coupled to the main EXV 28 by the first economizer output line 26 . The main EXV 28 is fluidly coupled to the evaporator 32 by the evaporator input line 30 . To complete the first fluid path 14 , the evaporator 32 is fluidly coupled to the compressor 16 by the suction line 34 .
[0022] The second fluid path 40 is defined by some of the components of the first fluid path 14 and is also defined by some additional components. The second fluid path 40 passes through the compressor 16 , the discharge line 18 , the condenser 20 , the economizer input line 22 (via the second branch 22 b ), a secondary EXV 42 , an economizer chamber 44 , and a second economizer output line 46 . Similar to the first fluid path 14 , in the second fluid path 40 , the compressor 16 is fluidly coupled to the condenser 20 by discharge line 18 . Also, the condenser 20 is coupled to the economizer 24 by economizer input line 22 .
[0023] The second branch 22 b of the economizer input line 22 is fluidly coupled to the secondary EXV 42 . The secondary EXV 42 is coupled via the second branch 22 b to the economizer chamber 44 , which is positioned within the economizer 24 . The refrigerant passing into the economizer chamber 44 via the second branch 22 b is in a heat transfer relationship with the refrigerant passing through the economizer 24 via the first branch 22 a . To complete the second fluid path 40 , the economizer chamber 44 is fluidly coupled to the compressor 16 by the second economizer output line 46 .
[0024] The refrigerant in its various states flows through the first fluid path 14 of the refrigerant circuit 12 as follows. Vaporized refrigerant is delivered to the compressor 16 by the suction line 34 . The compressor 16 compresses the vaporized refrigerant by increasing its temperature and pressure. The compressed, vaporized refrigerant is then delivered to the condenser 20 by the discharge line 18 . In a preferred embodiment of the invention, the compressor 16 is a screw-type compressor. However, the compressor 16 may be any appropriate type of compressor. Moreover, the refrigeration system 10 illustrated in FIG. 1 includes only a single compressor 16 . However, more than one compressor may be included in the refrigeration system 10 . If more than one compressor is included in the refrigeration system 10 , the compressors may be arranged in a series configuration or in a parallel configuration.
[0025] The condenser 20 receives compressed, vaporized refrigerant from the compressor 16 . The condenser 20 is a heat exchanger apparatus used to remove heat from the refrigerant in order to condense the vaporized refrigerant into liquid refrigerant. In the condenser 20 , the compressed, vaporized refrigerant releases heat to the air in communication with the condenser 20 in order to cool the vaporized refrigerant. The cooling action of the condenser 20 causes the state of the refrigerant to change from vapor to liquid.
[0026] While in the first fluid path 14 , the liquid refrigerant flows through the first branch 22 a of economizer input line 22 to the economizer 24 . As the refrigerant flows through the first branch 22 a , the refrigerant is in a heat transfer relationship with the refrigerant in the economizer chamber 44 . The refrigerant flowing through the first branch 22 a releases heat to the refrigerant in the economizer chamber 44 , thus sub-cooling the liquid refrigerant flowing through the first branch 22 a . Liquid refrigerant is sub-cooled when the temperature of the liquid is lower than its saturation or vaporization temperature at a given pressure. In general, both the condenser 20 and the economizer 24 sub-cool the liquid refrigerant, but the economizer 24 sub-cools the refrigerant more than the condenser 20 .
[0027] The sub-cooled liquid refrigerant is then delivered to the main EXV 28 by the first economizer output line 26 . The main EXV 28 is a throttling device that restricts the flow of the liquid refrigerant by forcing the liquid refrigerant through a small orifice. Forcing the liquid refrigerant through a small orifice causes the pressure of the liquid refrigerant to decrease thereby lowering the boiling temperature of the refrigerant. Reducing the pressure on the liquid refrigerant lowers the boiling point of the refrigerant, making the refrigerant evaporate. As the liquid refrigerant passes through the small orifice of the main EXV 28 , the liquid refrigerant forms into liquid droplets.
[0028] The liquid refrigerant droplets are delivered to the evaporator 32 by evaporator input line 30 . The liquid refrigerant droplets delivered to the evaporator 32 absorb heat from warm air flowing into the evaporator 32 . The evaporator 32 is located within or in thermal communication with the space being conditioned by the refrigeration system 10 . Air is generally circulated between the conditioned space and the evaporator 32 by one or more evaporator fans (not shown). Generally, warmer air flows into the evaporator 32 , the liquid refrigerant droplets absorb heat from the warmer air, and cooler air flows out of the evaporator 32 . The cooler air flowing out of the evaporator 32 cools the masses in the conditioned space by absorbing heat from the masses. Once the cooler air flowing out of the evaporator 32 absorbs heat from the masses within the conditioned space, the warmer air is circulated back to the evaporator 32 by the evaporator fans to be cooled again.
[0029] The liquid refrigerant droplets vaporize once they have absorbed sufficient heat, i.e. once the liquid refrigerant droplets reach their saturation or vaporization temperature at a given pressure. The refrigerant, which has changed from liquid refrigerant droplets back to vaporized refrigerant, is then delivered by suction line 34 back to the compressor 16 . The delivery of the vaporized refrigerant back to the compressor 16 completes the flow of refrigerant through the first fluid path 14 .
[0030] The refrigerant in its various states flows through the second fluid path 40 of the refrigerant circuit 12 as follows. Vaporized refrigerant is delivered to the compressor 16 by the second economizer output line 46 . Just as in the first fluid path 14 , the compressor 16 compresses the vaporized refrigerant by increasing the temperature and pressure of the vaporized refrigerant. The compressed, vaporized refrigerant is then delivered to the condenser 20 by discharge line 18 . In the condenser 20 , the compressed, vaporized refrigerant releases heat to the air in communication with the condenser 20 . The cooling action of the condenser 20 causes the state of the refrigerant to change from vapor to liquid. The liquid refrigerant exiting the condenser 20 is delivered to the economizer 24 by economizer input line 22 .
[0031] Some of the liquid refrigerant exiting the condenser 20 may be drawn off and directed through the second branch 22 b of the economizer input line 22 . The amount of liquid refrigerant drawn off and directed through the second branch 22 b is determined by the position of the secondary EXV 42 , among other things. Similar to the main EXV 28 , the secondary EXV 42 is a throttling device used to reduce the pressure and lower the boiling point the refrigerant. As the liquid refrigerant passes through the small orifice of the secondary EXV 42 , the liquid refrigerant forms into liquid refrigerant droplets.
[0032] The liquid refrigerant droplets from the secondary EXV 42 pass into the economizer chamber 44 , where the liquid refrigerant droplets are in a heat transfer relationship with the liquid refrigerant passing through the economizer 24 via the first branch 22 a . The liquid refrigerant droplets absorb heat from the liquid refrigerant passing through the first branch 22 a . The liquid refrigerant droplets vaporize once they have absorbed sufficient heat. The vaporization of the liquid refrigerant in the economizer compartment 44 further cools the liquid refrigerant passing through the first branch 22 a . Thus, the liquid refrigerant passing through the first branch 22 a of the economizer input line 22 is sub-cooled. Liquid refrigerant is sub-cooled when the temperature of the liquid refrigerant is lower than the saturation or vaporization temperature of the refrigerant at a given pressure.
[0033] Once all of the liquid refrigerant droplets in the economizer chamber 44 have vaporized, the vaporized refrigerant continues to absorb heat until the vaporized refrigerant is superheated. Refrigerant reaches a superheated level when the temperature of the refrigerant is above the vaporization or saturation temperature of the refrigerant at a given pressure. The vaporized refrigerant is then delivered to the compressor 16 via the second economizer output line 46 . The delivery of the vaporized refrigerant back to the compressor 16 completes the flow of refrigerant through the second fluid path 40 .
[0034] The microprocessor circuit 100 includes a plurality of sensors 102 coupled to the refrigerant circuit 12 and coupled to a microprocessor 104 . The microprocessor circuit 100 also controls the main EXV 28 coupled to the microprocessor 104 and the secondary EXV 42 coupled to the microprocessor 104 .
[0035] The plurality of sensors 102 includes a compressor discharge pressure (P D ) sensor 106 , a compressor discharge temperature (T D ) sensor 108 , a suction pressure (P S ) sensor 110 , a suction temperature sensor (T S ) 112 , an economizer pressure (P E ) sensor 114 , an economizer temperature (T E ) sensor 116 , an evaporator input temperature (T air,in ) sensor 118 , an evaporator output temperature (T air,out ) sensor 120 , and at least one sensor 122 coupled to the compressor 16 . Each one of the plurality of sensors 102 is electrically coupled to an input to the microprocessor 104 . Moreover, the main EXV 28 and the secondary EXV 42 are each coupled to an output of the microprocessor 104 .
[0036] In the preferred embodiment of the invention, as illustrated in FIG. 5, the above-described refrigeration system 10 is located within a refrigeration system housing unit 300 mounted on a transport container 302 . The transport container 302 is coupled to a tractor trailer 304 . Alternatively, the refrigeration system housing unit 300 may be coupled to any type of transport container unit coupled to any type of vehicle suitable for the transportation of goods, or to any type of vehicle (e.g. a truck or bus) that requires refrigeration.
[0037] [0037]FIG. 2 illustrates a method of operating the refrigeration system 10 in order to maintain a set of primary operating conditions. Referring to FIG. 1, the purpose of the set of primary operating conditions is to ensure that the superheat level of the refrigerant flowing from the economizer 24 to the compressor 16 is maintained, while enhancing the capacity of the refrigeration system 10 .
[0038] Referring to FIGS. 1 and 2, the microprocessor 104 reads 212 the economizer pressure (P E ) sensor 114 . The microprocessor 104 determines 214 a saturated temperature value (T sat ) from the P E value. T sat is determined from the P E value by consulting a thermodynamic properties look-up table for the particular type of refrigerant being used in the refrigeration system 10 . The thermodynamic properties look-up table is provided by the refrigerant manufacturer. A suitable type of refrigerant for this system is R404A refrigerant, which is manufactured by several companies, including E. I. duPont de Nemours and Company, AlliedSignal, Inc., and Elf Atochem, Inc.
[0039] Next, the microprocessor 104 reads 216 the economizer temperature (T E ) sensor 116 . The microprocessor 104 then determines 218 whether T E is greater than T sat . If T E is greater than T sat , the refrigerant being delivered from the economizer 24 to the compressor 16 is superheated. Thus, the refrigeration system is operating in a manner that ensures that liquid refrigerant will not be delivered from the economizer 24 through the second economizer output line 46 to the compressor 16 . As long as liquid is not currently being delivered to the compressor 16 , the flow of refrigerant through the secondary EXV 42 can be increased incrementally in order to increase the efficiency, and therefore the capacity, of the system. Accordingly, the microprocessor 104 sends a signal to the secondary EXV 42 to increase 220 the flow of refrigerant through the secondary EXV 42 . Once the microprocessor 104 sends the signal to increase the flow of refrigerant through the secondary EXV 42 , the microprocessor 104 begins the sequence again by performing act 200 .
[0040] If T E is less than T sat , the refrigerant being delivered from the economizer 24 to the compressor 16 is not superheated. In order to ensure that the superheat level of the refrigerant is maintained, the flow of refrigerant through the secondary EXV 42 can be decreased. Decreasing the flow through the secondary EXV 42 allows the refrigerant to absorb more heat while the refrigerant is in a heat exchange relationship with the refrigerant flowing through the first branch 22 a of the economizer input line 22 to the main EXV 28 . The refrigerant absorbs more heat to ensure that all of the liquid refrigerant is vaporized. Decreasing the flow through the secondary EXV 42 also decreases the pressure of the refrigerant being delivered back to the compressor 16 . In order to perform this step, the microprocessor 104 sends a signal to the secondary EXV 42 to decrease 222 the flow through the secondary EXV 42 . Once the microprocessor 104 sends the signal to decrease the flow through the secondary EXV 42 , the microprocessor 104 begins the sequence again by performing act 200 .
[0041] Typically, the capacity of a standard refrigeration system is controlled by either adjusting the speed of the compressor or by adjusting the position of the primary expansion valve (e.g., main EXV 28 ). In one aspect of the present invention, the capacity of the system is controlled by adjusting the position of the secondary EXV 42 . For example, if it is desired to reduce the capacity of the system, the secondary EXV 42 can be adjusted to a more closed position, thereby reducing the amount of refrigerant flowing through the economizer, which results in a reduction of the capacity of the system. Similarly, if there is a desire to increase the capacity of the system, the amount of refrigerant flowing through the secondary EXV 42 can be increased, thereby increasing the flow of refrigerant through the economizer, which increases the capacity of the system. It may be desirable to maintain feed back control on the system to ensure that the temperature of the refrigerant in the economizer output line 46 stays above the saturated temperature value for the given pressure to prevent delivery of liquid refrigerant to the compressor.
[0042] [0042]FIG. 3 illustrates another method of operating the refrigeration system 10 embodying the invention. While the method shown in FIG. 2 illustrates the operation of the refrigeration system 10 in order to maintain a set of primary operating conditions, FIG. 3 illustrates the operation of the refrigeration system 10 in order to maintain a first set of secondary operating conditions. Referring to FIG. 1, the purpose of the first set of secondary operating conditions is to quench the compressor 16 with liquid refrigerant if the compressor 16 overheats. Referring to FIGS. 1 and 3, the microprocessor 104 reads 240 the compressor discharge temperature (T D ) sensor 108 . The compressor discharge temperature (T D ) sensor 108 may be physically located between the compressor 16 and the condenser 20 or on the compressor 16 itself. A compressor discharge temperature threshold value (T threshold ) is provided 242 to the microprocessor 104 . The T threshold value is determined by the manufacturer of the particular compressor 16 being used in the refrigeration system 10 . A suitable compressor 16 for use in the refrigeration system 10 is a Thermo King Corporation double-screw compressor with a T threshold value of approximately 310° F. The value for T threshold may be stored in a memory location accessible by the microprocessor 104 .
[0043] The microprocessor 104 determines 244 whether T D is greater than T threshold . If T D is not greater than T threshold , the compressor 16 is operating within its temperature range, i.e. the compressor is not overheating. Accordingly, the microprocessor 104 sends a signal to the secondary EXV 42 to maintain 246 the primary operating conditions of the refrigeration system 10 by maintaining the current flow of refrigerant through the secondary EXV 42 . Once the microprocessor 104 sends the signal to maintain 246 the primary operating conditions, the microprocessor 104 begins the sequence again by performing act 240 . However, if T D is greater than T threshold , the compressor 16 may be overheating. The compressor 16 can be quenched by providing a combination of vapor and liquid refrigerant to the compressor 16 through the second economizer output line 46 . The refrigerant boils off of the compressor 16 in order to cool the compressor 16 to within its temperature operating range. In order to quench the compressor 16 , the primary operating conditions of the refrigeration system must first be overridden 248 , i.e. the flow of refrigerant to the compressor 16 must be increased even though the superheat level of the refrigerant flowing through the second economizer output line 46 will not be maintained while the compressor 16 is being quenched. Once the primary operating conditions are overridden 248 , the microprocessor 104 sends a signal to the secondary EXV 42 to increase 250 the flow of refrigerant through the secondary EXV 42 . Once the microprocessor 104 sends the signal to increase 250 the flow of refrigerant through the secondary EXV 42 , the microprocessor 104 begins the sequence again by performing act 240 . When T D is returned to a level less than T threshold , the microprocessor 104 can return to the primary operating conditions.
[0044] [0044]FIGS. 4A and 4B illustrate still another method of operating the refrigeration system 10 embodying the invention. FIGS. 4A and 4B illustrate the operation of the refrigeration system 10 in order to maintain a second set of secondary operating conditions. The purpose of the second set of secondary operating conditions is to prevent exceeding the horsepower output limit of the engine (not shown) that powers the compressor 16 . Referring to FIGS. 1 and 4A, the microprocessor 104 reads 270 the compressor discharge pressure (P D ) sensor 106 . The microprocessor 104 also reads 272 the compressor suction pressure (P S ) sensor 110 . Finally, the microprocessor 104 reads 274 the economizer pressure (P E ) sensor 114 .
[0045] A compressor map is provided 276 to the microprocessor 104 . The compressor map may be stored in memory locations accessible by the microprocessor 104 . Using the values for P D , P S , and P E , the microprocessor 104 accesses the compressor map and determines 278 the horsepower required (HP required ) by the compressor 16 for the current sensed pressures, the current compressor speed, and the current mass flow of refrigerant through the refrigeration system 10 . In order to determine the current compressor speed and the current mass flow of refrigerant, the microprocessor 104 reads at least one sensor 122 coupled to the compressor 16 . It should be appreciated that there are other ways to determine the required power of the system, all of which fall within the scope of the present invention.
[0046] Referring to FIG. 4B, an upper power limit in the form of a maximum horsepower output value (HP max ) is provided 280 to the microprocessor 104 . The HP max value is based on the maximum horsepower available from the compressor engine or prime mover (not shown). The HP max value for the compressor engine is provided by the manufacturer of the particular compressor engine and may be stored in memory accessible by the microprocessor 104 . The microprocessor 104 determines 282 whether HP required is greater than HP max . If HP required is not greater than HP max , enough horsepower is available from the engine powering the compressor 16 for the current mass flow of refrigerant through the refrigeration system 10 . Accordingly, the microprocessor 104 sends a signal to the secondary EXV 42 to maintain 284 the primary operating conditions by maintaining the current mass flow through the secondary EXV 42 . Once the microprocessor 104 sends the signal to maintain 284 the primary operating conditions, the microprocessor 104 begins the sequence again by performing act 270 .
[0047] However, if HP required is greater than HP max , the engine powering the compressor 16 will not be able to provide enough horsepower to the compressor 16 for the current flow of refrigerant through the refrigeration system 10 . In order to decrease the flow of refrigerant, the primary operating conditions must be overridden 286 and the flow through the secondary EXV 42 must be decreased 288 . Once the primary operating conditions are overridden 286 , the microprocessor 104 sends a signal to the secondary EXV 42 to decrease 288 the flow through the secondary EXV 42 . Once the microprocessor 104 sends the signal to decrease 288 the flow of refrigerant through the secondary EXV 42 , the microprocessor begins the sequence again by performing act 270 .
[0048] Various features and advantages of the invention are set forth in the following claims. | A method for controlling at least one electronic expansion valve coupled to an economizer in a refrigeration system in order to dynamically control the refrigeration system operating conditions and in order to accommodate more than one set of operating conditions. The system can also be used to control the capacity of the system. More specifically, the method can include determining the required capacity of the system and adjusting the flow of refrigerant through the electronic expansion valve to adjust the actual capacity of the system toward the required capacity of the system. In another aspect of the invention, the system is operated to maintain the power of the system below a threshold value (e.g., below a max rated horsepower). This method includes determining the power required to operate the compressor based on the measurement of system parameters; comparing the power required to a threshold value; and adjusting the flow of refrigerant through the electronic expansion valve in order to keep the power required below the threshold value. In yet another aspect of the invention, the system is operated in order to prevent overheating of the compressor. More specifically, the flow of refrigerant from the heat exchanger to the compressor can be adjusted so that some amount of liquid refrigerant is provided to quench the compressor. | 5 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] Related Application
[0002] This application is a continuation-in-part of co-pending and co-owned U.S. patent application Ser. No. 10/604,443, entitled “ Tornado and Hurricane Roof Tie” , filed with the U.S. Patent and Trademark Office on Jul. 22, 2003 by the inventor herein, which is a continuation-in-part of co-pending and co-owned U.S. patent application Ser. No. 10/211,138, entitled “ Tornado and Hurricane Roof Tie” , filed with the U.S. Patent and Trademark Office on Aug. 2, 2002 by the inventor herein, the specifications of which are included herein by reference.
BACKGROUND OF THE INVENTION
[0003] 1. Field of the Invention
[0004] This invention relates generally to building structures with wood roofs, and more particularly to structures exposed to extreme wind conditions, such as Tornadoes and Hurricanes, where building codes dictate that such structures be protected against structural failure to save lives of occupants. In particular, the present invention relates to a roof tie for anchoring a wood frame roof on a block construction building in order to resist uplift forces encountered during a high wind situation.
[0005] 2. Background of the Prior Art
[0006] It is well known what high winds can do to a building, particularly to a wood frame construction low-rise structure. Generally, uplift forces tending to lift the roof off the structure or the entire structure off its foundation cause much of the damage sustained by the building.
[0007] Wood structures predominate in residential and light commercial construction, and when wood framing is employed, the structure must be protected from upward loads developed by high wind, which differs with geographical location and is enforced by different building codes for such areas. For example, the Bahamas and Florida, including the Florida Keys are situated in the pathway of the yearly Caribbean hurricane travel course and as such, encounter hurricanes and/or tornadoes from time to time. Houses in the Bahamas are typically constructed of cement block with a wooden top plate fastened to the top of cement block walls, for attaching a wooden roof. In the case of upward loads, the roof is generally tied to the walls using a variety of steel connectors that tie the top plate to the walls. The size and number of these steel connectors vary depending on the severity of the wind conditions in the locality of the building, and the building's geometry. Due to the house location in a susceptible high wind area, some building codes require that houses built with wooden roof support beams have a “Hurricane Tie” in place on every rafter.
[0008] “Hurricane Ties” are usually installed during the foundation and framing stages of construction. Carpenters and laborers hired by the framing contractor generally install connectors and sheathing. Correct size, location, and number of fasteners (nails or screws) are critical to sustaining the required load. Commonly, such laborers are inexperienced, which results in improper or inadequate installation. The connectors are usually installed during the framing stage due to related components being placed at the same time. This process slows the foundation and framing stages of construction, which, in turn, increases labor costs.
[0009] From the foregoing, it is apparent that there is a critical need for a strong roof tie system that provides for uplift loads, which system is cost effective and easy to install.
SUMMARY OF THE INVENTION
[0010] The present invention provides a solution to the above and other problems by reinforcing and anchoring the roof structure to the building top plate for a wood construction building, wherein a hold down force is applied to the ceiling rafters to counter the uplift and horizontal forces generated by high winds. The present invention can be incorporated during initial construction of a wooden roof structure.
[0011] It is an object of the present invention to provide a roof-tie bracket system for a wooden roof structure of a building that reinforces the roof against damage in a high wind situation, such as a hurricane.
[0012] It is another object of the present invention to provide a roof-tie bracket system for a wooden roof construction building that provides a downward force around the periphery of the roof, thereby to better resist upward lift imparted to the roof by high winds.
[0013] It is another object of the present invention to provide a roof-tie bracket system for a wood frame roof that provides reinforcement to the roof structure, thereby providing greater resistance to damage during high wind conditions. A related object is to increase public safety in structures existing in high wind susceptible areas.
[0014] It is yet another object of the present invention to enable cost effective construction of wooden roof structures while meeting all building code requirements. A related object is to provide a roof-tie bracket system for a low-rise building that complies with the recommendation of all major building codes.
[0015] This invention relates to a novel roof-tie bracket system for bracing a wood framed roof of a building, e.g., a residential dwelling, having a structure including a foundation upon which rests a wall construction and horizontal ceiling top plates. The structure is reinforced against the destructive forces of the atmosphere by high strength brackets preferably attached to every rafter where it joins the ceiling plates. The roof-tie bracket is connected to the structure by way of a plurality of fasteners, such as nails or screws.
[0016] The roof-tie bracket disclosed herein offers more body, more nailing surfaces, more wrapping capability, more strength, and more durability to the purchasing public. Such roof-tie brackets may be made from a graduated increase in sheet metal gauges in a variety of straps or ties to fit many framing applications and strength requirements. Moreover, such roof-tie brackets may be pre-pitched to a predetermined angle of a roof, keeping in mind the different sizes of wood that may be used to pitch a roof. Such roof-tie brackets create a solid attachment between a rafter and ceiling top plate. This simple invention enables a family of roof-tie brackets that can be mass-produced and sold for a reasonable price that, in fact, can be made or put in place by any skilled or semi-skilled person.
[0017] Some of the advantages of this invention include: increase in surface area of a roof-tie bracket, thereby creating more surfaces through which nails could penetrate the substructure; “prepitched” roof-tie brackets that create a snug fit over all substructures and angles, at angles consistent with industry roof pitch standards; a wide aperture that allows fastening of nails through the roof sheaths to the rafter beneath; “plate flaps” that further secures the roof-tie bracket to the top plate; and, in some embodiments, a “U-shaped ceiling joist structure” that provides further for the “strapping” of ceiling joists, all in one simple Hurricane and Tornado Tie.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] The above and other features, aspects, and advantages of the present invention are considered in more detail, in relation to the following description of embodiments thereof shown in the accompanying drawings, in which:
[0019] [0019]FIG. 1 shows an illustration of a roof tie in perspective, according to one embodiment of the present invention;
[0020] [0020]FIG. 2 shows an illustration of an alternate perspective of the roof tie of FIG. 1;
[0021] [0021]FIG. 3 shows an illustration of the roof tie in perspective, with top plate and rafter in phantom;
[0022] [0022]FIG. 4 shows an illustration of an alternate perspective of the roof tie of FIG. 3, with a top plate and rafter in phantom;
[0023] [0023]FIG. 5 shows an illustration of a roof tie, according to an alternative embodiment of the present invention;
[0024] [0024]FIGS. 6 and 7 show an illustration of the roof tie in perspective, according to an additional alternate embodiment of the present invention;
[0025] [0025]FIG. 8 shows an illustration of the roof tie of FIG. 7, in perspective, showing a ceiling joist in place;
[0026] [0026]FIG. 9 shows an end view of the roof tie of FIG. 6;
[0027] [0027]FIG. 10 shows a close-up view of a portion of FIG. 6; and
[0028] [0028]FIG. 11 shows an illustration of a gable end roof tie according to the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0029] The invention summarized above and defined by the enumerated claims may be better understood by referring to the following description, which should be read in conjunction with the accompanying drawings in which like reference numbers are used for like parts. This description of an embodiment, set out below to enable one to build and use an implementation of the invention, is not intended to limit the enumerated claims, but to serve as a particular example thereof. Those skilled in the art should appreciate that they may readily use the conception and specific embodiments disclosed as a basis for modifying or designing other methods and systems for carrying out the same purposes of the present invention. Those skilled in the art should also realize that such equivalent assemblies do not depart from the spirit and scope of the invention in its broadest form.
[0030] Referring to FIGS. 1 and 2, a roof tie according to the present invention, indicated generally as 10 , is illustrated, comprising a pair of C-shaped tie components 13 , 15 , a U-shaped ceiling joist seat component 17 , and a bridge component 19 . The U-shaped ceiling joist seat component 17 has an upper portion 21 and a lower portion 24 . The upper portion 21 of such U-shaped ceiling joist seat component 17 comprises a wall 28 having a plurality of apertures 30 and at least one fastener slot, such as 32 . The lower portion 24 of such U-shaped ceiling joist seat component 17 comprises fastener extension 35 , which extends at a right angle from wall 28 and further comprises fixed top plate flap 38 , hinged top plate flap 40 , and short wall 43 . The fixed top plate flap 38 further comprises an appendage 44 , described in further detail below. The short wall 43 is disposed on an outward edge of fastener extension 35 and extends upward, substantially perpendicular to such fastener extension 35 . In general, the short wall 43 is preferably shorter than and substantially parallel to wall 28 . A plurality of apertures 30 for inserting fasteners, such as nails, are disposed on such fastener extension 35 , fixed top plate flap 38 , hinged top plate flap 40 , and short wall 43 . Such plurality of apertures should be disposed in a staggered fashion to prevent splitting of the top plate and rafters when inserting such fasteners.
[0031] Bridge component 19 presents a wide aperture area 46 to permit fastening decking to a rafter. Such bridge component 19 should be wide enough to conform to the standard thickness of construction materials, such as wooden 2×4s. Bridge component 19 comprises a short riser 48 having a plurality of apertures 30 for fastening such bridge component 19 to a rafter. In some embodiments, bridge component 19 can be counter sunk into the rafter in order to be flush with the top surface of such rafter. Bridge component 19 further comprises an overlap plate 51 disposed away from such bridge component 19 by ledge 53 and having at least one opening, such as 56 . In use, overlap plate 51 at least partly extends over wall 28 . The fastener slots 32 are disposed on wall 28 such that, in use, fasteners inserted in openings 56 in overlap plate 51 can penetrate such fastener slots 32 . By having such overlap, roof tie 10 can adapt to rafters of varying heights for application in a variety of construction scenarios. Fastener slots 32 enable fasteners to be inserted in such a manner to ensure a snug fit for bridge component 19 on the top of a rafter. Overlap plate 51 extends over wall 28 , such that fasteners inserted in openings 56 also enter fastener slots 32 at a variable position depending on the height of the rafter, for attachment to the rafter.
[0032] Tie components 13 , 15 present mirror images of each other. Each tie component 13 , 15 has an upper portion 60 and a lower portion 62 . The upper portion 60 of such tie component comprises a riser 65 having a plurality of apertures 30 . The C-shaped lower portion 62 of such tie component comprises fastener extension 67 , which extends at a right angle from riser 65 and further comprises a top plate flap 70 with an appendage 73 . Appendage 73 extends inwardly at a right angle from top plate flap 70 . Top plate flap 70 is sized and configured such that appendage 73 can fit under a top plate to form a three-sided wrap with fastener extension 67 and top plate flap 70 . In some embodiments, top plate flap 70 is sized and configured such that appendage 73 may be embedded into a side of the top plate. In such an embodiment, appendage 73 should penetrate approximately ¾-inch into the wood top plate; the inner edge 74 of appendage 73 may be sharpened to enable such penetration. (Appendage 44 of the fixed top plate flap 38 of such U-shaped ceiling joist seat component 17 is configured in the same manner.) A plurality of apertures 30 for inserting fasteners, such as nails, are disposed on said fastener extension 67 , and top plate flap 70 .
[0033] Each tie component 13 , 15 further comprises a turnbuckle 75 attached to bridge component 19 and fastener extension 67 . Turnbuckle 75 comprises body 78 having a first threaded portion 81 extending out of the top of body 78 and a second threaded portion 83 extending out of the bottom of body 78 . Body 78 is internally threaded for mating with such first and second threaded portions 81 , 83 . The distal end of such first threaded portion 81 terminates in an eye 86 having an opening for attaching to short riser 48 of bridge component 19 . The eye 86 can be attached to short riser 48 by a suitable fastener, such as a nail or lag bolt. In some embodiments, short riser 48 presents a hook on which such eye 86 can be attached. In an additional embodiment, short riser 48 presents a track 90 in which an adjustable hook or other appropriate fastener can be variably positioned. The distal end of such second threaded portion 83 terminates in an eye or some other fashion for attachment to plate 93 attached to fastener extension 67 by suitable fasteners.
[0034] The alignment of the threads of such first and second threaded portions 81 , 83 is configured such that rotation of body 78 in a first direction about its longitudinal axis causes both such first and second threaded portions 81 , 83 to be drawn into body 78 and rotation of body 78 in a second, opposite direction about its longitudinal axis causes both such first and second threaded portions 81 , 83 to be forced out of body 78 . The roof tie 10 provides additional reinforcement against uplift forces encountered in a high wind condition, resulting in a sturdier, stronger tie. Such increased strength can be obtained at reduced cost by enabling use of lower galvanized steel gauges for its construction while providing increased hold-down force.
[0035] Bridge component 19 can be variably pitched and retrofitted to existing roof applications, especially for roof trusses. The turnbuckles can be adjusted, up or down, as necessary to provide sufficient hold down tension and to conform to the pitch of the roof.
[0036] For heavy-duty applications, or as an optional feature, roof tie 10 may further comprise a reinforcing wing 95 on tie components 13 , 15 . Such reinforcing wing 95 is generally triangular in shape and extends outward from riser 65 with the lower edge of reinforcing wing 95 attached to the inner edge of fastener extension 67 . Such reinforced roof tie 10 provides vertical reinforcement to prevent balking while enabling increased rigidity to roof tie 10 , resulting in a sturdier, stronger roof tie 10 . The increased strength can be obtained at reduced cost by enabling use of lower galvanized steel gauges for its construction. Balking is caused by misalignment of trusses due to warping of roof timbers or loosening of fastened joints, resulting in roof decking being heaved up along such misaligned roof truss.
[0037] An application showing use of roof tie 10 is illustrated in FIGS. 3 and 4 presenting roof tie 10 in a position for fastening to top plate 98 and rafter 99 . Fasteners are attached to top plate 98 and rafter 99 through apertures 30 , and through openings 56 in alignment with fastener slots 32 . Using a fastener in each aperture and opening ensures a strong and secure attachment. Additional embodiments using various numbers of holes can be used based on specific engineering requirements as determined by one skilled in the art.
[0038] As shown in FIG. 3, hinged top plate flap 40 can be rotated into approximately the same plane as fastener extension 35 to enable appendage 44 to be fastened into one side of top plate 98 ; then, hinged top plate flap 40 can be rotated substantially perpendicular to the fastener extension 35 providing a wrap around most of such top plate 98 . Fixed top plate flap 38 and hinged top plate flap 40 are attached to top plate 98 with a plurality of suitable fasteners through apertures 30 . Bridge component 19 straddles rafter 99 and is attached to rafter 99 with a plurality of fasteners, as described above. Wide aperture area 46 is provided to enable fastening of decking material to rafter 99 .
[0039] As shown in FIG. 4, tie components 13 , 15 are attached to top plate 98 to enable appendage 73 to be fastened into each side of top plate 98 . Turnbuckle 75 is attached to bridge component 19 . Fastener extension 35 and top plate flap 70 are attached to top plate 98 with a plurality of suitable fasteners through apertures 30 . If necessary, turnbuckle 75 can be adjusted to provide sufficient hold down tension.
[0040] In some embodiments, the length of the forward edge of wall 28 may be longer than the rear edge of wall 28 in order to have bridge component 19 angled to correspond to a selected pitch for a roof. In such cases, the turnbuckles 75 of tie components 13 , 15 can be adjusted to appropriate lengths to conform to the pitch of the roof.
[0041] [0041]FIG. 5 shows an illustration of an application according to an alternative roof tie embodiment. Roof tie 100 comprises two pair of matching tie components 103 , 105 , 107 , 109 attached to either side of bridge component 112 . Each tie component 103 , 105 , 107 , 109 comprises a riser 115 having a plurality of apertures for inserting fasteners, such as nails therethrough and a fastener extension 117 , which extends at a right angle from riser 115 and further comprises a top plate flap 119 with an appendage 123 . Appendage 123 extends inwardly at a right angle from top plate flap 119 . Top plate flap 119 is sized and configured such that appendage 123 can fit under top plate 125 to form a three-sided wrap with fastener extension 117 and top plate flap 119 . In some embodiments, top plate flap 119 is sized and configured such that appendage 123 may be embedded into a side of the top plate 125 . In such an embodiment, the inner edge 127 of appendage 123 may be sharpened to enable penetration into wooden top plate 125 . A plurality of apertures 130 for inserting fasteners, such as nails are disposed on fastener extension 117 and top plate flap 119 .
[0042] Each tie component 103 , 105 , 107 , 109 further comprises a turnbuckle 133 attached to bridge component 112 and fastener extension 117 . Turnbuckle 133 comprises a body 138 having a first threaded portion 141 extending out of the top of body 138 and a second threaded portion 143 extending out of the bottom of body 138 . Body 138 is internally threaded for mating with such first and second threaded portions 141 , 143 . The distal end of such first threaded portion 141 terminates in an eye 146 having an opening for attaching to bridge component 112 . The eye 146 can be attached to bridge component 112 by a suitable fastener, such as a nail or lag bolt. The distal end of such second threaded portion 143 terminates in an eye or some other fashion for attachment to plate 150 attached to fastener extension 117 by suitable fasteners.
[0043] The alignment of the threads of such first and second threaded portions 141 , 143 is configured such that rotation of said body 138 in a first direction about its longitudinal axis causes both such first and second threaded portions 141 , 143 to be drawn into body 138 and rotation of body 138 in a second, opposite direction about its longitudinal axis causes both such first and second threaded portions 141 , 143 to be forced out of body 138 . Each turnbuckle 133 on tie components 103 , 105 , 107 , 109 is separately adjustable. Such roof tie 100 provides additional reinforcement against uplift forces encountered in a high wind condition, resulting in a sturdier, stronger tie. The increased strength can be obtained at reduced cost by enabling use of lower galvanized steel gauges for its construction while providing increased hold-down force.
[0044] For heavy-duty applications, or as an optional feature, roof tie 100 may further comprise a reinforcing wing 155 on tie components 103 , 105 , 107 , 109 . The reinforcing wing 155 is generally triangular in shape and extends outward from riser 115 with the lower edge of reinforcing wing 155 attached to an edge of fastener extension 117 . Such reinforced roof tie 100 provides vertical reinforcement to prevent balking while enabling increased rigidity to roof tie 100 , resulting in a sturdier, stronger roof tie 100 . The increased strength can be obtained at reduced cost by enabling use of lower galvanized steel gauges for its construction. Balking is caused by misalignment of trusses due to warping of roof timbers or loosening of fastened joints, resulting in roof decking being heaved up along such misaligned roof truss.
[0045] Referring to FIGS. 6 - 9 , an adjustable roof tie 200 is shown. Roof tie 200 comprises a pair of C-shaped tie components 205 , 207 , of similar construction as described with reference to FIGS. 1 and 2, a bridge component 210 , also of similar construction as described with reference to FIGS. 1 and 2, and a U-shaped ceiling joist seat component 213 . The U-shaped ceiling joist seat component 213 comprises two slidably engaged connector sections 217 , 219 , each having an upper portion and a lower portion. The upper portion 221 of connector section 217 comprises a wall 224 having a plurality of apertures. The lower portion 226 of connector section 217 comprises fastener extension 229 , which extends at a right angle from wall 224 and further comprises top plate flap 231 . The top plate flap 231 further comprises an appendage 235 that extends inwardly at a right angle from top plate flap 231 . Top plate flap 231 is sized and configured such that appendage 235 can fit under a top plate to form a three-sided wrap with fastener extension 229 and top plate flap 231 . In some embodiments, top plate flap 231 is sized and configured such that appendage 235 may be embedded into a side of the top plate. In such an embodiment, appendage 235 should penetrate approximately {fraction (3/4)}-inch into the wood top plate; the inner edge 236 of appendage 235 may be sharpened to enable such penetration. At least one slot, such as 240 , is disposed in fastener extension 229 .
[0046] Connector section 219 comprises fastener extension 243 having a short wall 246 disposed on an outward edge of fastener extension 243 , which extends upward, substantially perpendicular to such fastener extension 243 . The lower portion 248 of connector section 219 further comprises top plate flap 251 . The top plate flap 251 is configured similar to top plate flap 231 and comprises an appendage that extends inwardly at a right angle from top plate flap 251 . Top plate flap 251 is sized and configured such that the appendage can fit under a top plate to form a three-sided wrap with fastener extension 243 and top plate flap 231 . In some embodiments, top plate flap 251 is sized and configured such that the appendage may be embedded into a side of the top plate. In such an embodiment, the appendage should penetrate approximately {fraction (3/4)}-inch into the wood top plate; the inner edge of the appendage may be sharpened to enable such penetration. Fastener extension 243 overlaps fastener extension 229 . A plurality of apertures 255 for inserting fasteners, such as nails, are disposed on such fastener extension 243 , top plate flaps 231 , 251 , and short wall 246 . Such plurality of apertures should be disposed in a staggered fashion to prevent splitting of the top plate and rafters when inserting such fasteners. Some apertures 255 disposed in fastener extension 243 should align with the at least one slot 240 disposed in fastener extension 229 . By having such overlap, roof tie 200 can adapt to top plates of varying widths for application in a variety of construction scenarios. Fastener slot 240 enable fasteners to be inserted in such a manner to ensure a snug fit for U-shaped ceiling joist seat component 213 on the top plate. Fastener extension 243 extends over fastener extension 229 , such that some fasteners inserted in apertures 255 also enter fastener slots 240 at a variable position depending on the width of the top plate, for attachment to the top plate. When roof tie 200 is attached to top plate 98 and rafter 99 , a ceiling joist 258 can be set in the U-shaped ceiling joist seat component 213 , as shown in FIG. 8. Fasteners, such as nails or screws can be inserted through apertures 255 to attach roof tie 200 to the ceiling joist 258 .
[0047] In some embodiments, both the wall 224 and the short wall 246 may be attached to the same fastener extension, such that the remaining slidably engaged connector section comprises only the fastener extension, top plate flap, and the appendage, for adjustable fit on a top plate.
[0048] Tie components 205 , 207 present mirror images of each other. Such tie component 205 , 207 are of similar construction as described with reference to FIGS. 1 and 2. Referring to FIG. 9, the C-shaped lower portion of tie components 205 , 207 comprises fastener extension 208 , a top plate flap 209 with an appendage 211 . Appendage 211 extends inwardly at a right angle from top plate flap 209 . Top plate flap 209 is sized and configured such that appendage 211 can fit under a top plate to form a three-sided wrap with fastener extension 208 and top plate flap 209 . In some embodiments, and as particularly shown in FIG. 9, top plate flap 209 is sized and configured such that appendage 211 may be embedded into a side of the top plate. In such an embodiment, appendage 211 should penetrate approximately ¾-inch into the wood top plate; the inner edge 212 of appendage 211 may be sharpened to enable such penetration.
[0049] Referring to FIG. 10, each tie component 205 , 207 is connected to bridge component 210 by a turnbuckle 260 . Turnbuckle 260 comprises body 262 having a pair of threaded portions 265 extending out of the top and bottom of body 262 . Body 262 is internally threaded for mating with such threaded portions 265 . The alignment of the threads of such threaded portions 265 is configured such that rotation of body 262 in a first direction about its longitudinal axis causes both such threaded portions 265 to be drawn into body 262 and rotation of body 262 in a second, opposite direction about its longitudinal axis causes both such threaded portions 265 to be forced out of body 262 . The outer end of each such threaded portion 265 forms a pivotable attachment 268 to a hinge plate 271 . Hinge plate 271 is hingedly attached to bridge component 210 and tie component 205 , 207 by a hinge and pin assembly 275 .
[0050] The backside of a gable end roof tie 300 is shown in FIG. 11. The front side of such gable end roof tie 300 is similar to the roof tie shown and described with reference to FIG. 3. In some embodiments, such front side will not include short wall 43 . The remaining portion of gable end roof tie 300 comprises a tie plate 303 and a bridge component 305 having a wide aperture area 308 to permit fastening decking to a rafter. Such bridge component 305 should be wide enough to conform to the standard thickness of construction materials, such as wooden 2×4s. Bridge component 305 comprises a short riser 311 having a plurality of apertures 314 for fastening such bridge component 305 to a rafter.
[0051] Tie plate 303 includes an appendage 317 that extends inwardly at a right angle from tie plate 303 . Appendage 317 may be embedded into the butt end of top plate 320 . The inner edge of appendage 317 may be sharpened to enable penetration into top plate 320 . A plurality of apertures 314 for inserting fasteners, such as nails is disposed on tie plate 303 . Tie plate 303 is connected to bridge component 305 by at least one turnbuckle 260 . Turnbuckle 260 comprises body 262 having a pair of threaded portions 265 extending out of the top and bottom of body 262 . Body 262 is internally threaded for mating with such threaded portions 265 . The alignment of the threads of such threaded portions 265 is configured such that rotation of body 262 in a first direction about its longitudinal axis causes both such threaded portions 265 to be drawn into body 262 and rotation of body 262 in a second, opposite direction about its longitudinal axis causes both such threaded portions 265 to be forced out of body 262 . The outer end of each such threaded portion 265 forms a pivotable attachment 268 to hinge plate 271 . Hinge plate 271 is hingedly attached to the short riser 311 of bridge component 305 and tie plate 303 by a hinge and pin assembly 275 . As shown, the turnbuckles can be adjusted up or down, forward or backwards to enable bridge component 305 to conform to a pitched roof and provide sufficient hold down tension.
[0052] The invention has been described with references to a preferred embodiment. While specific values, relationships, materials and steps have been set forth for purposes of describing concepts of the invention, it will be appreciated by persons skilled in the art that numerous variations and/or modifications may be made to the invention as shown in the specific embodiments without departing from the spirit or scope of the basic concepts and operating principles of the invention as broadly described. It should be recognized that, in the light of the above teachings, those skilled in the art can modify those specifics without departing from the invention taught herein. Having now fully set forth the preferred embodiments and certain modifications of the concept underlying the present invention, various other embodiments as well as certain variations and modifications of the embodiments herein shown and described will obviously occur to those skilled in the art upon becoming familiar with such underlying concept. It is intended to include all such modifications, alternatives and other embodiments insofar as they come within the scope of the appended claims or equivalents thereof. It should be understood, therefore, that the invention may be practiced otherwise than as specifically set forth herein. Consequently, the present embodiments are to be considered in all respects as illustrative and not restrictive. | A building roof tie for attaching roof trusses and rafters to wood top plates in building structures, said roof tie having a sheet metal body with risers and a bridge for overlapping a rafter and flaps for wrapping on the sides of the top plate. The flaps may be configured to penetrate into the top plate for additional stability. Turnbuckles attached to the bridge provide additional hold-down strength against increased uplift forces. Such turnbuckles may include a hinge and pin assembly that can adjust up and down, forward and backwards. The roof ties are pitched to conform to a variety of framing applications. A plurality of apertures is formed in the roof tie to provide openings for fasteners for connecting the tie to the wood top plate and rafter. | 4 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation of International Application No. PCT/CN2010/071237, filed on Mar. 24, 2010, which claims priority to Chinese Patent Application No. 200910119782.X, filed on Mar. 26, 2009, both of which are hereby incorporated by reference in their entireties.
FIELD
The present disclosure relates to the mobile communication field, and in particular, to a prefix allocation method, a network system, and a Local Mobility Anchor (LMA).
BACKGROUND
Proxy Mobile IP (PMIP) is widely applied on the Worldwide Interoperability for Microwave Access (WiMAX) network, 3rd Generation Partnership Project (3GPP) System Architecture Evolution (SAE) network, and network systems for interworking between the 3GPP network and the WiMAX network. Generally, as shown in FIG. 1 , the basic architecture of a PMIPV6 system includes:
An Authentication, Authorization and Accounting (AAA) server, which provides access authentication and authorization for the MN to access the network. Generally, on the 3GPP SAE network, the AAA server coexists with a Home Subscriber Server (HSS) that stores the subscription information of the MN. If the AAA server is separate from the HSS, the AAA server may communicate with the HSS to obtain the subscription information of the MN.
A Mobile Node, MN and a Correspondent Node, CN, being a pair of communication nodes in a point-to-point service application, and the communication nodes are corresponding to a network device such as a terminal or a server.
A Mobile Access Gateway (MAG) and a Local Mobile Anchor (LMA) are the basic network elements in the PMIPv6 system and are generally located on the gateway of access network and the gateway of core network respectively.
The basic mechanism of the PMIPv6 system is as follows: after the MN attaches to the network where the MAG is located, the MAG completes registration on behalf of the MN, and the MAG simulates a home link to advertise a Home Network Prefix (HNP) to the MN. In this way, the MN is made to think itself always located on the home link, so that the MN does not need to support mobility management.
As shown in FIG. 2 , the general process of allocating an HNP by the PMIPv6 system includes the following steps:
S 101 , the MN attaches to the network where the MAG is located. S 102 , the MAG sends a first access request for the MN to the AAA server. S 103 , the AAA server returns a first access response to the MAG, where the access response includes service configuration information of the MN, that is, service information (including service type and Service QoS and authorization information (key materials allocated to the MN). S 104 , the MAG on behalf of the MN, sends a registration message (that is, a Proxy Binding Update (PBU) message) to the LMA. S 105 , the LMA sends a second access request for the MN to the AAA server. S 106 , the AAA server returns a second access response. S 105 and S 106 are optional. S 107 , the LMA allocates an HNP to the MN according to the received PBU, creates a Binding Cache Entry (BCE) regarding the HNP and a Proxy Care-of Address (PCoA) (generally referred to as the IP address of the MAG), where the BCE includes a mapping relationship between the MN ID, the HNP, and the PCoA, and acts as a proxy of the MN to send a neighbor advertisement in which the link layer address corresponding to the HNP that is allocated to the MN is asserted to be the link layer address of the LMA. S 108 , the LMA returns a Proxy Binding Acknowledge (PBA) message, which carries the HNP information allocated to the MN, to the MAG S 109 , the MAG stores the HNP information, and sends a Router Advertisement (RA), which carries the HNP, to the MN. S 110 , after the MN receives the RA, the MN generates a home address according to the HNP.
In the preceding basic mechanism of PMIPv6, the HNP that the LMA allocates to the MN is exclusive. That is, the LMA allocates a unique HNP to each MN, and any two MNs do not have the same HNP. Furthermore, if multiple interfaces (IFs) of an MN are attached to the network through different access technologies and are connected to the LMA, the LMA allocates different HNPs to multiple IFs of the MN.
A shared prefix is in contrast to an exclusive prefix. An HNP is used by multiple MNs, or by multiple IFs of an MN. However, the conventional PMIPv6 and MN do not support the shared prefix.
As an intelligent MN is more capable of supporting multiple IFs (that is, each IF may be attached to the network through different access technologies), the multi-IF enabled MN has more requirements for some service applications. For example, services of the multi-IF enabled MN need to be attached to the network via multiple IFs of the MN to obtain more bandwidths, or services of the multi-IF enabled MN need to be handed over between different IFs to ensure load balancing. If the same prefix (that is, the shared prefix) is used by two or more IFs of the MN, the continuity of services/sessions in such requirements can be guaranteed.
During the implementation of the present disclosure, the inventor discovers at least the following problems in the prior art:
Because the multi-IF enabled MN has multiple IFs, the conventional system cannot determine which IFs need to be allocated with a shared prefix after being attached to the network. In addition, because an IF of the MN can have one or more prefixes, the conventional system cannot determine which prefix is shared with other IFs. Therefore, the problem about how to allocate a shared prefix to the multi-IF enabled MN should be solved as soon as possible.
SUMMARY
Embodiments of the present disclosure provide a prefix allocation method, a network system, and an LMA to solve the problem that a shared prefix cannot be allocated to a multi-IF enabled MN.
A prefix allocation method includes: receiving a registration request for a second IF of an MN from an MAG; according to the registration request, obtaining a first HNP that is already allocated to a first IF of the MN; and allocating the first HNP shared with the first IF to the second IF.
A network system includes: an MAG, configured to send a registration request for a second IF of an MN to an LMA; and the LMA, configured, according to the registration request sent from the MAG, to obtain a first HNP that is already allocated to a first IF of the MN, and allocate the first HNP shared with the first IF to the second IF.
An LMA includes: a receiving module, configured to receive a registration request for a second IF of an MN from an MAG; a prefix obtaining module, configured, according to the registration request received by the receiving module, to obtain a first HNP that is already allocated to a first IF of the MN; and an allocating module, configured to allocate the first HNP shared with the first IF and obtained by the prefix obtaining module to the second IF.
In embodiments of the present disclosure, an LMA receives a registration request for a second IF of an MN from an MAG and according to the registration request, the LMA obtains a first HNP that is already allocated to a first IF of the MN, and allocates the first HNP to the second IF of the MN. With the embodiments of the present disclosure, a shared prefix is allocated to the multi-IF enabled MN, and the multi-IF enabled MN can obtain more bandwidths for a same service that has the shared prefix or a service can be handed over between IFs that have the shared prefix, thus ensuring the load balancing and continuity of services/sessions.
BRIEF DESCRIPTION OF THE DRAWINGS
To make the present disclosure or the prior art clearer, the accompanying drawings for illustrating the embodiments of the present disclosure or the prior art are briefly described. Apparently, the accompanying drawings are merely exemplary, and those skilled in the art can derive other drawings from such accompanying drawings without creative efforts.
FIG. 1 is a schematic architecture diagram of a PMIPv6 system in the prior art;
FIG. 2 is a signaling flowchart of allocating an HNP by the PMIPv6 system in the prior art;
FIG. 3 is a schematic flowchart of a prefix allocation method according to an embodiment of the present disclosure;
FIG. 4 is a schematic diagram of an extended HNP option according to an embodiment of the present disclosure;
FIG. 5 a is a schematic diagram of an extended Router Solicitation (RS) message according to an embodiment of the present disclosure;
FIG. 5 b is a schematic diagram of an extended Internet Control Message Protocol (ICMP) mobile prefix request according to an embodiment of the present disclosure;
FIG. 6 is a schematic diagram of a prefix information option according to an embodiment of the present disclosure;
FIG. 7 is a signaling flowchart of a prefix allocation method according to an embodiment of the present disclosure;
FIG. 8 is a structure diagram of a network system according to an embodiment of the present disclosure;
FIG. 9 is a structure diagram of an LMA according to an embodiment of the present disclosure;
FIG. 10 is a structure diagram of a multi-IF enabled MN according to an embodiment of the present disclosure;
FIG. 11 is a schematic diagram of a relationship between a managing module, a service/application module, an Internet Protocol (IP) module, and an IF on a multi-IF enabled MN according to an embodiment of the present disclosure; and
FIG. 12 is a structure diagram of an MAG according to an embodiment of the present disclosure.
DETAILED DESCRIPTION OF THE EMBODIMENTS
To make the objective, features, and merits of the present disclosure clearer and understandable, the embodiments of the present disclosure are described in detail with the accompanying drawing.
The method provided in embodiments of the present disclosure is based on the fact that a first HNP (HNP 1 ) is already allocated to a first interface (IF 1 ) of an MN. The process of allocating the HNP 1 to the IF 1 is the same as the process of allocating an HNP by the PMIPv6 system in the conventional art.
A prefix allocation method is provided in a first embodiment of the present disclosure. As shown in FIG. 3 , after a second interface (IF 2 ) of the MN attaches to a network where a MAG is located, the method includes the following steps:
S 301 Receive a registration request for the IF 2 of the MN from the MAG
After the IF 2 of the MN attaches to the network where the MAG is located, the MAG sends a registration request to the LMA on behalf of the IF 2 .
The (initial) registration request that the MAG sends to a LMA in this embodiment refers to a PBU message. The PBU message may include an MN ID (for example, the network access identifier (NAI)), PCoA bound to the requested prefix, and other information data (for example, the access technology type of the IF 2 of the MN). The PBU message may further include information data such as whether the MN supports the shared prefix and a service type associated with the IF 2 . In this embodiment, an S flag bit, which indicates that the shared prefix is supported, is added to an extended HNP option (as shown in FIG. 4 ) to indicate the request for the shared prefix. Optionally, the obtained HNP 1 information data is included; if such information data is not included, the prefix length is 0. Further, indication information data, which indicates that the MN supports the shared prefix, is added to an extended registration message to indicate whether the MN supports the shared prefix model.
S 302 According to the registration request, obtain the HNP 1 that is already allocated to the IF 1 of the MN.
In this embodiment, the LMA may obtain the HNP 1 in the following two modes:
In the first mode, the registration request that the LMA receives from the MAG carries information data for helping obtain the HNP 1 .
In the second mode, the registration request that the LMA receives from the MAG does not carry information data for helping obtain the HNP 1 .
In the first mode, the method, provided in the embodiment of the present disclosure, provides three types of information data for helping obtain the HNP 1 in the registration request. The registration request carries the HNP 1 , or a prefix list that includes at least the HNP 1 , or a service type associated with the IF 2 .
In this case, the scenarios that the LMA obtains the HNP 1 are specifically included as follows:
(1) When the registration request carries the HNP 1 , the LMA obtains the HNP 1 from the registration request.
The HNP 1 carried in the registration request comes from a data link layer message or a network layer message that is sent by the MN via the IF 2 and received by the MAG.
(i) An L 3 message that the MN sends to the MAG via the IF 2 carries the HNP 1 information data. Specifically, the L 3 message is a new L 3 message extended on the basis of an existing L 3 message or a newly defined L 3 message.
Preferably, the L 3 includes an extended option to carry the HNP 1 . The L 3 message may include an RS message or an ICMP mobile prefix request message.
The following describes the method by extending the existing RS and the ICMP mobile prefix request, as shown in FIG. 5 a and FIG. 5 b:
An S flag bit is added to the RS or the ICMP message, and is used to indicate a request for a shared prefix. The extended message may include a prefix information option, that is, the HNP 1 that is already allocated to the IF 1 of the MN in this embodiment. The prefix information option specifically includes the following contents (as shown in FIG. 6 ): type of the prefix information option, option length, prefix length, on-link flag L, automatic configuration flag A, optional route address flag R, reserved bit 1 , valid life cycle, preferred life cycle, reserved bit 2 , and prefix.
Optionally, the L 3 message that the multi-IF enabled MN sends to the MAG further carries an option of service type associated with the IF 2 , where the option is used to carry the service type associated with the IF 2 .
In this embodiment, the process of the sending, by the MN, an L 3 message to the MAG to request a shared prefix may be implemented independently. That is, in some scenarios, an IF of the MN may actively request a known HNP or IP address.
(ii) The link layer L 2 message that the MN sends to an access point such as a Base Station (BS) via the IF 2 carries the HNP 1 information. The access point sends the HNP 1 information to the MAG.
Preferably, the L 2 message includes an extended option to carry the HNP 1 .
On the WiMAX access network based on the 802.16/802.16e wireless technology, preferably, the L 2 message may include a request/acknowledgement message of an initial traffic flow or pre-configuration traffic flow.
Optionally, the L 2 message that the multi-IF enabled MN sends to the MAG further carries a flag bit that indicates that the IF 2 supports the shared prefix, indicating that the MN is capable of supporting the shared prefix.
Optionally, the L 2 message that the multi-IF enabled MN sends to the MAG further carries an option of service type associated with the IF 2 , where the option is used to carry the service type associated with the IF 2 .
(2) When the registration request carries a prefix list that includes at least the HNP 1 , the LMA matches the prefix list with prefixes in the locally stored binding entry of the MN, and obtains the same HNP 1 .
In this embodiment, the local refers to the LMA.
Preferably, when only one prefix is available in the prefix list of the IF 2 that the MAG extracts from the service configuration information of the IF 2 , that is, only the HNP 1 is included in the prefix list, the LMA may directly obtain the HNP 1 after receiving a registration request that carries only the HNP 1 , and does not need to perform the matching.
In this embodiment, one service type uses one prefix (a shared prefix) of one or more IFs.
Conventionally, the service configuration information is stored on the AAA server, and includes service information and authorization information related to the subscription of users and the operator. The service information includes service type and service QoS, and the authorization information includes a key allocated to the MN and a charging index. The Remote Authentication Dial in User Service (RADIUS) or the Diameter protocol may be used between the MAG and the AAA server. If the RADIUS protocol is used, the first access response should be an Access Accept message, and the first access request should be a RADIUS Accept Request message.
On the basis of the conventional art, the service configuration information, in this embodiment, further includes IF information corresponding to the service information. The IF information includes a prefix list corresponding to the IF, and a mapping relationship between services and prefixes in the prefix list. Preferably, the service configuration information further includes indication information indicating whether the MN supports the shared prefix.
When the IF 2 of the MN attaches to the network, in the process of initiating, by the MAG the first authentication to the AAA server, the MAG receives from the AAA server a first access response that carries the service configuration information of the MN or the IF 2 . Optionally, the service configuration information further includes information about whether the MN supports the shared prefix.
The prefix list is extracted by the MAG from the first access response returned by the AAA server, where the first access response carries the service configuration information of the MN or the IF 2 . When the first access request that the MAG sends to the AAA server carries an MN ID, the first access response returned by the AAA server carries the service configuration information of the MN. When the first access request that the MAG sends to the AAA server carries the MN ID and the IF 2 ID, the first access response returned by the AAA server carries only the service configuration information of the IF 2 .
In the actual deployment, the LMA performs a first authentication process and/or a second authentication to obtain the service configuration information of the MN.
The prefix information list is a prefix list that extracted from the service configuration information of the MN carried in the first access response that the MAG receives from the AAA server.
After receiving the registration request, the LMA matches the prefix information list with the service type carried by the IF 2 , so as to obtain the HNP 1 that corresponds to the same service type.
Preferably, after the MAG receives the HNP 1 allocated by the LMA, the MAG sends a request (on the basis of the Diameter or RADIUS protocol) to the AAA server, and sends information, which the IF 2 is served by the MAG to the AAA server.
(3) When the registration request carries the service type associated with the IF 2 , the LMA matches the service type associated with the IF 2 with a service type in the binding entry, stored locally, of the MN, and obtains the HNP 1 corresponding to a same service type.
When the registration request carries the service type associated with the IF 2 , the LMA obtains the HNP 1 by matching the same service type in the binding entry, stored on the LMA, of the MN with the service type associated with the IF 2 . The binding entry may include an MN identity, an HNP of an IF, and service type corresponding to the HNP.
The service type associated with the IF 2 of the MN in the registration request may come from the first access response that the AAA server returns to the MAG; where the first access response carries the service configuration information of the IF 2 , and the MAG extracts the service type associated with the IF 2 from the service configuration information. Alternatively, the service type may come from an link layer L 2 message or an network layer L 3 message that the MN sends to the MAG, and the link layer L 2 message or the network layer L 3 message carries the service type associated with the IF 2 in an extended option.
For the second mode, the method provided in this embodiment provides two approaches for the LMA to obtain the HNP 1 .
(4) The LMA extracts the service type associated with the IF 2 from the second access response returned by the AAA server, where the second access response carries the service configuration information of the MN or the IF 2 . The LMA matches the service type associated with the IF 2 with a service type in the binding entry, stored locally, of the MN, and obtains the HNP 1 corresponding to the same service type.
According to the MN ID or the IF 2 ID carried in the registration request, the LMA sends a second access request, which carries an MN ID or carries an MN ID and an IF 2 ID, to the AAA server.
The service configuration information, compared with the conventional art, further includes IF information corresponding to the service information, where the IF information includes a prefix list corresponding to the IF. If the first access request includes an IF identity of the MN, the service configuration information corresponding to the IF of the MN is returned; if the first access request does not include the IF identity of the MN, all the service configuration information of the MN is returned. Preferably, the service configuration information further includes indication information indicating whether the MN supports the shared prefix.
Preferably, in this obtaining mode, after the LMA allocates the HNP 1 to the IF 2 , the LMA sends information that the IF 2 of the MN is served by the LMA to the AAA server.
(5) The LMA extracts a prefix list that includes at least the HNP 1 from the second access response returned by the AAA server, where the second access response carries the service configuration information of the MN or the IF 2 . Then, the LMA matches the prefix list with prefixes in the binding entry, stored locally, of the MN, and obtains the same HNP 1 .
Preferably, when only one prefix is available in the prefix list of the IF 2 that the LMA extracts from the service configuration information of the IF 2 , that is, only the HNP 1 is included in the prefix list, the LMA may directly obtain the HNP 1 according to a shared prefix indication, and does not need to perform the matching.
S 303 Allocate the HNP 1 shared with the IF 1 to the IF 2 .
After the LMA obtains the HNP 1 , the LMA allocates the HNP 1 shared with the IF 1 to the IF 2 .
In this embodiment, the allocation process is as follows: the LMA creates a binding entry for the IF 2 , and stores, in a binding entry, the HNP 1 , a lifetime of the HNP 1 , service information corresponding to the HNP 1 , and information about whether the shared prefix is supported. The MN ID, IF information (for example, the IF identity, the access type, and other IF related information) of the MN, and the PCoA are also stored in the binding entry.
Preferably, before the LMA allocates the HNP 1 to the IF 2 , the LMA determines, according to the indication information that indicates whether the MN supports the shared prefix and is carried in the registration request, whether the MN supports the shared prefix; if the MN supports the shared prefix, the LMA allocates the HNP 1 to the IF 2 .
The indication information, which indicates th at the MN supports the shared prefix and is carried in the registration request, includes:
indication information that indicates that the MN supports the shared prefix and is extracted by the MAG from an L 2 message or an L 3 message that the MN sends via the IF 2 , where the L 2 message or the L 3 message carries the indication information, which indicates that the MN supports the shared prefix, in an extended flag bit; or
indication information that indicates that the MN supports the shared prefix and is extracted by the MAG from a first access response returned by the AAA server, where the first access response carries service configuration information.
Preferably, before the LMA allocates the HNP 1 to the IF 2 , the LMA may determine whether the service type associated with the IF 2 is the same as the service type corresponding to the HNP 1 ; if the service type associated with the IF 2 is the same as the service type corresponding to the HNP 1 , the LMA allocates the HNP 1 to the IF 2 .
In this embodiment, when multiple prefixes are already allocated to one or more IFs and another IF requests the shared prefix, the prefix list of the new IF carried in the service configuration information returned by the AAA server may include multiple prefixes same as those of other IFs. When the LMA receives the prefix list and matches the prefix list with the binding entry, stored on the LMA, of the MN, the LMA obtains one or multiple shared prefixes. The LMA allocates these shared prefixes to the new IF to achieve the objective of allocating shared prefixes to a multi-IF enabled MN. Preferably, before allocating these shared prefixes to the new IF, the LMA determines whether the MN supports the shared prefix, and/or matches the service type associated with the new IF with a locally stored service type associated with other IFs of the MN, so as to determine which shared prefixes should be allocated to the new IF.
As shown in FIG. 7 , the method provided in an embodiment of the present disclosure includes the following steps:
In step S 701 , the IF 2 of the MN attaches to a network where the MAG 2 is located.
In step S 702 , the MAG 2 sends a registration request to the LMA.
The (initial) registration request that the MAG 2 sends to the LMA may include an MN ID (for example, the NAI), PCoA bound to the requested prefix, and other information (for example, the access technology type of the IF 2 of the MN). The registration request may further include the HNP 1 requested by the IF 2 , or a prefix list that includes at least the HNP 1 , or the service type associated with the IF 2 , and include indication information that indicates whether the MN supports the shared prefix.
In step S 703 , the LMA obtains the HNP 1 that is already allocated to the IF 1 .
The LMA may obtain the HNP 1 that is already allocated to the IF 1 in the following modes:
When the registration request carries the HNP 1 , the LMA obtains the HNP 1 from the registration request, where the HNP 1 carried in the registration request comes from the L 2 message or L 3 message that the MN sends to the MAG via the IF 2 .
Alternatively, when the registration request carries a prefix list that includes at least the HNP 1 , the LMA matches the prefix list with prefixes in the binding entry, stored on the LMA, of the MN, and obtains the same HNP 1 , where the prefix list is extracted by the MAG from the first access response which is returned by the AAA server and carries the service configuration information of the MN or the IF 2 .
Alternatively, when the registration request carries the service type associated with the IF 2 , The LMA matches the service type associated with the IF 2 with a service type in the binding entry, stored on the LMA, of the MN, and obtains the HNP 1 corresponding to the same service type.
Alternatively, the LMA extracts the service type, carried by the IF 2 , from the second access response returned by the AAA server, where the second access response carries the service configuration information of the MN or the IF 2 , matches the service type associated with the IF 2 with a service type in the binding entry, stored on the LMA, of the MN, and obtains the HNP 1 corresponding to the same service type.
In step S 704 , the LMA allocates the HNP 1 to the IF 2 of the MN.
Preferably, before the LMA allocates the HNP 1 to the IF 2 of the MN, the LMA determines whether the MN supports the shared prefix. If the MN supports the shared prefix, then step S 704 is performed.
Preferably, before the LMA allocates the HNP 1 to the IF 2 of the MN, the LMA may determine whether the service type associated with the IF 2 is the same as the service type corresponding to the HNP 1 . If the service type associated with the IF 2 is the same as the service type corresponding to the HNP 1 , then step S 704 is performed.
Whether the MN supports the shared prefix is determined according to the indication information that indicates that the MN supports the shared prefix and is carried in the registration request. The indication information, which indicates that the MN supports the shared prefix and carried in the registration information, may include:
indication information that indicates that the MN supports the shared prefix and is carried in the L 2 message or the L 3 message that the MN sends via the IF 2 ; or
indication information that indicates that the MN supports the shared prefix and is extracted by the MAG from the first access response returned by the AAA server, where the first access response carries the service configuration information.
Preferably, after the LMA allocates the HNP 1 to the IF 2 , the LMA sends information that the IF 2 is served by the LMA to the AAA server.
In addition, when the MN does not support the shared prefix or when the service type associated with the IF 2 is different from the service type corresponding to the HNP 1 , the LMA allocates a new home network prefix, HNP 2 , to the IF 2 of the MN or generates a failure code indicating that the shared prefix is not allowed to use.
Preferably, the method further includes S 705 , that is, the LMA carries the HNP 1 allocated to the IF 2 in a registration response, and returns the registration response to the MAG 2 .
In this embodiment, the registration response returned by the LMA refers to a PBA message. After the MAG 2 receives the registration response, the MAG 2 creates a second BCE (BCE 2 ) for the IF 2 , where the BCE 2 may include a mapping relationship between the MN ID, the IF 2 ID, and the PCoA 2 , and a corresponding LMA.
Preferably, the method further includes S 706 , that is, the MAG 2 returns the HNP 1 to the MN.
If the LMA allocates the HNP 1 to the IF 2 , the MAG 2 returns the HNP 1 to the MN through an RA after receiving, from the LMA, a registration response that includes the HNP 1 .
Optionally, the extended RA message carries a shared prefix flag bit.
Preferably, the method further includes S 707 , that is, the MN configures a home address, which is same as that of the IF 1 , for the IF 2 .
The IF 2 of the MN performs IP address configuration according to the shared prefix to carry out the subsequent service handover or service use.
The IP address that the MN configures for the IF 2 is the same as or different from the IP address configured for the IF 1 . If the IP address of the IF 2 is the same as that of the IF 1 , the MN may directly request the IP address when obtaining the HNP 1 .
Through the method provided in this embodiment, after receiving a registration request for the IF 2 of the MN, the LMA obtains an HNP 1 that is already allocated to the IF 1 of the MN, and allocates the HNP 1 to the IF 2 . With the method provided in this embodiment, a shared prefix is allocated to the multi-IF enabled MN, and the multi-IF enabled MN can obtain more bandwidths for a same service that has the shared prefix; or a service can be handed over between IFs that have the shared prefix, thus ensuring the load balancing and continuity of services/sessions.
An embodiment of the present disclosure provides a network system. As shown in FIG. 8 , the network system includes an MAG 110 and an LMA 120 .
A MAG 110 is configured to send a registration request for an IF 2 of a MN to a LMA 120 .
The LMA 120 is configured, according to the registration request sent from the MAG 110 , to obtain an HNP 1 that is already allocated to an IF 1 of the MN, and allocate the HNP 1 shared with the IF 1 to the IF 2 .
Preferably, the MAG 110 is further configured to obtain an HNP 1 , or a prefix list that includes at least the HNP 1 , or a service type associated with the IF 2 , and carry the HNP 1 , the prefix list, or the service type associated with the IF 2 in the registration request.
Preferably, the step of obtaining the HNP 1 that is already allocated to the IF 1 of the MN is as follows: when the registration request carries the HNP 1 , the LMA 120 obtains the HNP 1 from the registration request; or when the registration request carries a prefix list that includes at least the HNP 1 , the LMA 120 matches the prefix list with the prefixes in the binding entry, stored on the LMA 120 , of the MN, and obtains the same HNP 1 ; or when the registration request carries a service type associated with the IF 2 , the LMA 120 matches the service type associated with the IF 2 with a service type in the binding entry, stored on the LMA 120 , of the MN, and obtains the HNP 1 corresponding to the same service type.
Preferably, the step of obtaining the HNP 1 that is already allocated to the IF 1 of the MN is as follows: the LMA 120 extracts the service type associated with the IF 2 from a second access response returned by a AAA server, where the second access response carries the service configuration information of the MN or the IF 2 , matches the service type associated with the IF 2 with a service type in the binding entry, stored on the LMA 120 , of the MN, and obtains the HNP 1 corresponding to the same service type.
Preferably, the step of obtaining the HNP 1 that is already allocated to the IF 1 of the MN is as follows: the LMA 120 extracts a prefix list that includes at least the HNP 1 from a second access response returned by the AAA server, where the second access response carries the service configuration information of the MN or the IF 2 , matches the prefix list with prefixes in the binding entry, stored on the LMA 120 , of the MN, and obtains the same HNP 1 .
Preferably, the MAG 110 is further configured to obtain indication information that the MN supports the shared prefix, and carry, in the registration request, the indication information that the MN supports the shared prefix.
Preferably, the LMA 120 is further configured to determine whether the MN supports the shared prefix according to the indication information, which indicates that the MN supports the shared prefix and is carried in the registration request sent from the MAG 110 , before allocating the HNP 1 to the IF 2 .
Preferably, the network system 10 further includes: an AAA server 130 configured to: perform first access authentication on the MAG 110 and return a first access response; perform second access authentication on the LMA 120 and return a second access response; and store the service configuration information of the MN.
In this embodiment, when the network system receives a registration request for the IF 2 of the MN, the network system obtains an HNP 1 , which is allocated to the IF 1 of the MN, through the LMA, and allocates the HNP 1 to the IF 2 . The network system provided in this embodiment allocates a shared prefix to a multi-IF enabled MN, and the multi-IF enabled MN can obtain more bandwidths for a same service that has the shared prefix; or a service can be handed over between IFs that have the shared prefix, thus ensuring the load balancing and continuity of services/sessions.
An embodiment of the present disclosure provides an LMA. As shown in FIG. 9 , the LMA includes:
a receiving module 1201 , configured to receive a registration request for the IF 2 of the MN from the MAG;
a prefix obtaining module 1202 , configured, according to the registration request received by the receiving module 1201 , to obtain an HNP 1 that is already allocated to the IF 1 of the MN; and
an allocating module 1203 , configured to allocate the HNP 1 , which is shared with the IF 1 and is obtained by the prefix obtaining module 1202 , to the IF 2 .
Preferably, the prefix obtaining module 1202 includes one or any combination of the following units:
a first unit, configured to obtain the HNP 1 from the registration request when the registration request carries the HNP 1 ;
a second unit, configured to: when the registration request carries a prefix list that includes at least the HNP 1 , match the prefix list with prefixes in the binding entry, stored on the LMA 120 , of the MN, and obtain the same HNP 1 ;
a third unit, configured to: when the registration request carries the service type associated with the IF 2 , match the service type associated with the IF 2 with a service type in the binding entry, stored on the LMA 120 , of the MN, and obtain the HNP 1 corresponding to the same service type;
a fourth unit, configured to: extract the service type, carried by the IF 2 , from a second access response returned by the AAA server, where the second access response carries the service configuration information of the MN or the IF 2 , match the service type associated with the IF 2 with a service type in the binding entry, stored on the LMA 120 , of the MN, and obtain the HNP 1 corresponding to the same service type;
a fifth unit, configured to: extract a prefix list that includes at least the HNP 1 from a second access response returned by the AAA server, where the second access response carries the service configuration information of the MN or the IF 2 , match the prefix list with prefixes in the binding entry, stored on the LMA 120 , of the MN, and obtain the same HNP 1 .
Preferably, the LMA 120 further includes:
a module 1204 for obtaining information that shared prefix is supported, configured to obtain indication information that indicates that the MN supports the shared prefix and is carried in the registration request; and
the allocating module 1203 , further configured to determine whether the MN supports the shared prefix according to indication information that indicates that the MN supports the shared prefix and is carried in the registration request.
In this embodiment, after the LMA receives a registration request for the IF 2 of the MN, the LMA obtains an HNP 1 that is already allocated to the IF 1 of the MN, and allocates the HNP 1 to the IF 2 , thus allocating a shared prefix to a multi-IF enabled MN.
An embodiment of the present disclosure provides a multi-IF enabled MN. As shown in FIG. 10 , the multi-IF enabled MN includes a sending module 210 , a receiving module 220 , and an address generating module 230 .
The sending module 210 is configured to send an L 2 message or an L 3 message that carries an HNP 1 to the MAG via the IF 2 after the HNP 1 is already allocated to the IF 1 of the MN and the IF 2 of the MN attaches to the network where the MAG is located.
The receiving module 220 is configured to receive an HNP returned by the MAG.
The address generating module 230 is configured to generate a home address according to the HNP received by the receiving module 220 .
Preferably, the MN 20 further includes a managing module 240 configured to: manage the request, sent by the sending module 210 , for a shared prefix of the IF, manage a shared home address generated by the address generating module 230 according to the shared prefix, and control the service handover between multiple IFs that have the shared home address.
Preferably, the MN 20 further includes a service/application module 250 , an IP module 260 , and an IF 270 .
The service/application module 250 is configured to provide users with services/applications.
The IP module 260 is configured to provide the services/applications of the service/application module 250 with functions such as TCP/IP or UDP/IP.
The IF 270 is configured to connect to same/different access networks through the IP module 260 .
The relationship between the managing module 240 , the service/application module 250 , the IP module 260 , and the IF 270 is shown in FIG. 11 . The managing module 240 , according to the policy information, determines whether the service is connected to the network at the same time via multiple IFs 270 , or hands over the service from one IF 270 to another IF 270 , or performs other operations. In addition, the managing module determines whether the IF 270 needs to allocate the shared prefix to another IF 270 .
The policy information refers to the policy information between the service/application module 250 and the IF 270 managed by the managing module 240 . The policy information may include: QoS needed by the service and the QoS of the link (the bandwidths and delays obtained via the 3G IF are different from the bandwidths and delays obtained via the Wireless Fidelity (WiFi) IF) corresponding to the IF 270 , and service expenses and expenses (for example, expenses of the same service may vary with interfaces adopted, e.g., via the 3G IF and the WiFi IF) caused by the link corresponding to the IF 270 . Alternatively, the policy information refers to the status information of the IF 270 managed and/or sensed by the managing module 240 . For example, when an IF 270 is overloaded or the IF 270 is disconnected (for example, the MN moves outside the network coverage), the managing module 240 can hand over the services/applications from an IF 270 to another IF 270 .
In this embodiment, the multi-IF enabled MN manages the request for and use of the IF prefix; after the network obtains the HNP that is already allocated to an IF of the MN, and allocates the HNP to another IF subsequently attached, the MN may generate a shared home address according to the shared prefix, and the service of the multi-IF enabled MN may be connected to the network, via multiple IFs of the MN, to obtain more bandwidths; and the service of the multi-IF enabled MN may be handed over between different IFs, thus guaranteeing the load balancing and continuity of services/sessions.
An embodiment of the present disclosure provides an MAG As shown in FIG. 12 , the MAG includes a prefix obtaining module 1101 , a registration request generating module 1102 , a registration request sending module 1103 , and a prefix returning module 1104 .
The prefix obtaining module 1101 is configured to obtain the HNP 1 after the HNP 1 is allocated to the IF 1 of the MN and the IF 2 of the MN attaches to the network where the MAG 110 is located.
The registration request generating module 1102 is configured to generate the registration request that carries the HNP 1 obtained by the prefix obtaining module 1101 .
The registration request sending module 1103 is configured to send the registration request to the LMA.
Preferably, the prefix obtaining module 1101 includes a first obtaining unit configured to obtain the HNP 1 from the registration request when the registration request carries the HNP 1 , where the HNP 1 carried in the registration request comes from an L 2 message or an L 3 message that the MN sends to the MAG 110 via the IF 2 .
Preferably, the prefix obtaining module 1101 includes a second obtaining unit configured to: when the registration request carries a prefix list that includes at least the HNP 1 , match the prefix list with prefixes in the binding entry, stored on the LMA, of the MN, and obtain the same HNP 1 , where the prefix list is extracted by the MAG from a first access response which is returned by the AAA server and includes the service configuration information data of the MN or the IF 2 .
Preferably, the prefix obtaining module 1101 includes a third obtaining unit configured to: when the registration request carries the service type associated with the IF 2 , match the service type associated with the IF 2 with a service type in the binding entry, stored on the LMA, of the MN, and obtain the HNP 1 corresponding to the same service type.
Preferably, the MAG 110 further includes a prefix returning module 1104 configured to return the HNP that the LMA allocates to the IF 2 to the MN.
In this embodiment, after the IF 2 of the MN attaches to the network where the MAG is located, the MAG obtains the HNP 1 that is already allocated to the IF 1 of the MN, and sends a registration request that carries the HNP 1 to the LMA; after an HNP is allocated to the IF 2 of the MN, the MAG returns the HNP to the MN, thus allocating a shared prefix to a multi-IF enabled MN.
The method, network system, and LMA provided in embodiments of the present disclosure are also applicable for a scenario where multiple prefixes are already allocated to one or more IFs (for example, IF 1 ) of the MN, or where multiple prefixes shared with other IFs are allocated to a new IF (for example, the IF 2 ).
The embodiments of the network system, the LMA, the multi-IF enabled MN, and the MAG according to the present disclosure are described briefly because of similar contents with the embodiments of the proxy allocation method mentioned above. For details, please refer to the description of method embodiments provided in the present disclosure.
It is understandable to those skilled in the art that all or some of the steps of the method are completed by hardware instructed by a program. The program may be stored in a computer readable storage medium. When the program is executed, the process includes: receiving a registration request for the IF 2 of the MN from the MAG; according to the registration request, obtaining an HNP 1 that is already allocated to the IF 1 of the MN; and allocating the HNP 1 shared with the IF 1 to the IF 2 . The storage medium may be a Read Only Memory or Random Access Memory (ROM/RAM), a magnetic disk, or a Compact Disk-Read Only Memory (CD-ROM).
The above descriptions are merely exemplary embodiments of the present disclosure, but not intended to limit the protection scope of the present disclosure. Any modification, equivalent replacement, or improvement made without departing from the spirit and principle of the present disclosure should fall within the protection scope of the present disclosure. | The present disclosure relates to the mobile communication field and discloses a prefix allocation method, a network system, and a Local Mobility Anchor (LMA). With the prefix allocation method, the network system and the LMA provided in the present disclosure, the problem that a shared prefix cannot be allocated to a multi-interface (IF) Mobile Node (MN) is solved. The prefix allocation method includes: receiving a registration request for a second IF of the MN from a Mobile Access Gateway (MAG); obtaining a first Home Network Prefix (HNP) that is already allocated to a first interface (IF) of the MN; and allocating the first HNP shared with the first IF to the second IF. The LMA obtains the first HNP that is already allocated to the first IF and allocates the first HNP to the second IF. In this way, a shared prefix is allocated to the multi-IF enabled MN. | 7 |
BACKGROUND OF THE INVENTION
The present invention relates to a modular food package particularly suitable for use in the fast food industry, and more particularly to a modular package that can be used as a stand alone, open ended, scoop type, package suitable for containing food items, such as french fries, potato cakes, cookies, pies, and such, or two, identical, units may be combined to create a completely enclosed, and interlocking package for a sandwich or other appropriate food items.
At present the prior art, in the fast food industry, provides open ended, or scoop type, packages particularly for fast food items such as french fries and potato cakes. Such packaged food items, when placed within a bag for carryout service, typically fall over spilling the contents of the open ended package. Further, within the fast food industry, larger food items, such as specialty sandwiches, are typically wrapped with a paper covering, placed within an open ended package, and delivered to the purchaser.
SUMMARY OF THE PRESENT INVENTION
By the present invention, a modular, open ended, or scoop type, fast food package is disclosed and taught that may be used as a stand alone, open ended package and/or two such, identical, open ended packages may be opposingly combined to form a totally enclosed package. Fast food packages, in accord with the teachings of the present invention, may be specifically configured to serve a multiplicity of food items such as french fries, potato cakes, and cookies, or may be configured for serving sandwich items. In either situation, two identical, open ended packages may be combined to form a fully enclosed food containing, modular package. Thus, fast food packages no longer need to be carefully placed within carryout bags to prevent inadvertent spillage. Further, by use of the herein disclosed fast food package a single, open ended, package may be used for in-store service of a food item, such as a sandwich, while the combined modular package may be used for take-out service. Thus an open end package may be used for in-store service and an enclosed package used for take-out service without additional cost or inventory.
The improved interlocking, open ended package as disclosed and taught herein comprises a collapsed scoop type package (convenient for bulk shipping the package to the end user) having either a pop-up or automatic type bottom so that when opened for use it forms a scoop type fast food package having a back wall portion extending upward from the main package portion. Extending from the back wall to the front wall of the package, at each side thereof, is a sloped portion of each side wall which will telescopingly slide inside an opposing package thereby forming a fully enclosed package. The sloped portion of each side wall meets the front wall forming a "V" type notch therebetween. As two packages are telescopingly brought together the front wall of one package slides upward along the sloped side walls of the other. When two of the packages are telescopingly brought together the notches of one package interlock with the notches of the opposing package thereby interlocking one with the other thereby forming a fully enclosed package. By providing a notch at the juncture of each side wall and front wall, a front wall tongue is thereby formed at the free edge of the front wall extending between the notches. When two packages are brought together, as described above, the front wall tongue of one package overrides the tongue of the other package providing a closure therebetween.
By use of the herein disclosed modular package a single, open ended, package might be used for in-store service of a food item such as a sandwich while the combined modular package might be used for take-out service.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 presents a pictorial view of a first embodiment of a modular, open ended, pop-up, scoop type, fast food package embodying the present invention in its expanded configuration and ready for use.
FIG. 2 presents a cross sectional view taken along line 2--2 in FIG. 1.
FIG. 3 presents a cross sectional view taken along line 3--3 in FIG. 1.
FIG. 4 presents a plan view of a unitary paperboard blank from which the package as illustrated in FIG. 1 is formed.
FIG. 5 presents a planar view of the paperboard blank, shown in FIG. 4, after its first folding operation, during manufacture, thereby producing a first perform.
FIG. 6A presents a planar view of the paperboard blank, shown in FIG. 4, after its second folding operation thereby producing a second perform.
FIG. 6B presents a planar view of the paperboard blank, shown in FIG. 4, flipped over 180 degrees thereby showing the front side of the second perform.
FIG. 7 presents a pictorial view of two of the open ended packages, as illustrated in FIG. 1, being telescoped, one into the other, to form a unique enclosed fast food package.
FIG. 8 presents a pictorial view of the final enclosed fast food package formed by telescoping two of the packages, as illustrated in FIG. 7.
FIG. 9 presents a pictorial view of a second embodiment of the present invention illustrating an, elongated, modular, open ended, auto-bottom, fast food package in its expanded configuration and ready for use.
FIG. 10 presents a cross sectional view taken along line 10--10 in FIG. 9.
FIG. 11 presents a cross sectional view taken along line 11--11 in FIG. 9.
FIG. 12 presents a plan view of a unitary paperboard blank from which the package as illustrated in FIG. 9 is formed.
FIG. 13 presents a planar view of the paperboard blank, as shown in FIG. 12, after its first folding operation during manufacture.
FIG. 14 presents a planar view of the paperboard blank, as shown in FIG. 12, after its second folding operation during manufacture.
FIG. 15 presents a planar view of the paperboard blank, as shown in FIG. 12, after its third folding operation during manufacture.
FIG. 16A presents a planar view showing the paperboard blank, as shown in FIG. 12, after its fourth and final folding operation during manufacture.
FIG. 16B presents a planar view showing the paperboard blank, as shown in FIG. 16A flipped over 180 degrees to show the front side thereof.
FIG. 17 presents a pictorial view of two of the open ended packages, as illustrated in FIG. 9, being telescoped, one into the other, to form a unique enclosed fast food package.
FIG. 18 presents a pictorial view of the final enclosed fast food package formed by telescoping two of the packages, as illustrated in FIG. 9.
FIG. 19 presents a cross sectional view taken along line 19--19 in FIG. 8.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
FIGS. 1 through 3 generally illustrate a first embodiment of an open ended, modular fast food package 100, made in accord with the present invention, particularly suitable for serving fast food of the sandwich type.
Referring additionally to FIG. 4, the unitary blank 102 is typically cut from a sheet of suitable paperboard, or other stiff bendable and resilient sheet material in the configuration as shown. Blank 102 includes a generally rectangular front and rear wall, 104 and 106 respectively, separated by a pop-up bottom panel 108. The back wall may be provided a cut out 110 as shown which will be discussed in further detail below. Opposing arcuate, perforated fold lines 112 and 114 separate bottom panel 108 from front wall 104 and back wall 106 respectively. Bisecting bottom panel 108 is perforated fold line 116. Extending from either side of front wall 104 are right and left side walls (as viewed in FIG. 1) 120 and 122. The bottom edges 124 and 126, of end wall 120 comprise segments 124A and 124B. The length of segments 124A, and 124B correspond to, and are slightly longer than, segments 134A and 134B, of bottom panel 108. Similarly, segments 126A and 126B, of bottom edge 126 of left side wall 122, are slightly longer than corresponding segments 136A and 136B of bottom panel 108.
Top edge 130 and 132 of right and left walls 120 and 122, respectively, comprise straight line segments 130A, 130B, 132A, and 132B as best shown in FIG. 4. Although segments 130A, 130B, 132A, and 132B are disclosed as being straight line segments, these segments may also be curved if desired. End walls 120 and 122 also include scored fold lines 140, 142, 144, 150, 152, and 154 as best seen in FIG. 4. Fold line 142 is positioned approximately midway between fold line 140 and 144 and fold line 152 is positioned approximately midway between fold lines 150 and 154. For assembly each end wall 120 and 122 is provided a glue tab 146 and 148 respectively.
Front wall 104 terminates, at top edge 138 which meets the right and left end wall edge segments 130A and 132A forming notches 156 and 158 there between as best illustrated in FIG. 4. Front wall top edge 138 forms a tongue 128 with respect to imaginary line 118 extending between the bottom of notches 156 and 158.
Assembly of the subject package is accomplished first by folding the back wall 106, of blank 102, upward, as viewed in FIG. 4, about fold line 116 of bottom panel 108, so as to lie over top of front wall 104 forming a first perform 160 as illustrated in FIG. 5. The outer portion of right and left end walls 120 and 122, extending outward from fold lines 142 and 152 respectively, are then folded, about fold lines 142 and 152 upward, from the plane of FIG. 5 as indicated by the arrows, so as to overlie the inward portion of each respective end wall and a portion of back wall 106 thereby forming a second perform 165 as illustrated in FIG. 6A. When end walls 120 and 122 are folded over top of back wall 106 and adhesively secured to back wall 106 by adhesive strips 162 and 164 on tabs 146 and 148. FIG. 6B illustrates the front side of the perform 165 as illustrated in FIG. 6A. Perform 165 is the final perform and represents the flat configuration by which the subject package is shipped.
To open perform 165 for use, the end user expandingly separates the front and back walls, 104 and 106, whereby causing end walls 120 and 122 to fill the gap created there between and snap the bottom wall 108 upward between the front and back wall about fold lines 114 and 112 thereby creating the open package 100 as illustrated in FIGS. 1 through 3.
Referring now to FIGS. 7, 8, and 19, two identical, open ended, fast food packages, as illustrated in FIG. 1, 100L and 100R are illustrated as being assembled (package 100L telescoping into package 100R) to form a composite, enclosed, fast food package 200 as illustrated in FIG. 8.
To form enclosed package 200 the left and right projections 182 and 184 (see FIG. 1) of package 100L (now identified by element numbers 182L and 184L) are telescopingly inserted inside left and right projections 182R and 184R of package 100R as illustrated in FIG. 7. When packages 100L and 100R are combined to form enclosed package 200, as illustrated in FIG. 8, tongue 128L, of package 100L, over laps tongue 128R, of package 100R, as illustrated in FIG. 19 forming a closure therebetween. Cutout 100R, see FIG. 7, permits the fast food purchaser to grip the front and rear wall of package 110L for easy separation of the modular package halves 100L and 100R for removal of the food item therein. Further, if cutout 110 is given a large radius of curvature, as shown in FIGS. 1 through 6, a food item, such as a sandwich, may be consumed while being held within the package half.
A fast food package in accord with the present invention may be provided with any number of configurations and/sizes. The size and configuration will typically be determined by the particular food product delivered therein. For example a package configured to accommodate a sandwich type product may have a rear wall height approximately equal to the width of the package thereby accommodating a typical round sandwich product, or the rear wall height may extend upward approximately twice the height of the package width to accommodate an elongate food product such as french fried potatoes. Such an elongated package is illustrated below.
Referring now to FIGS. 9 through 11, a second embodiment of the present invention is illustrated. Fast food package 200 is particularly suited for serving elongated fast foods such as french fries. Similar to the discussion for the sandwich type package 100 above, reference to left and right sides of package 200 will be as the package 200 is viewed in FIG. 9 with the left side wall indicated as element number 210 and the front wall identified by element number 204.
Referring additionally to FIG. 12, a unitary blank 202 is typically cut from a sheet of suitable paperboard, or other stiff bendable and resilient sheet material in the configuration as shown. Blank 202 includes a generally rectangular front and rear wall, 204 and 206 respectively. Between front wall 204 and back wall 206 is right side wall 208. Left side wall 210 extends from the opposite side of front wall 204 as illustrated. Glue tab 212 extends from back wall 206.
Scored fold line 214 separates back wall 206 from glue tab 212. Scored fold lines 216 and 218 flank right side wall 208 thereby defining and separating right side wall 208 from back wall 206 and front wall 204 as illustrated in FIG. 12. Similarly scored fold line 220 separates front wall 204 from left side wall 210.
Top edge 230 and 232 of right and left walls 208 and 210 generally comprise straight line segments as best shown in FIG. 12. Although segments 230, and 232 are disclosed as being straight line segments, these segments may also be curved if desired. Straight line segments 230 and 232 curvingly terminate at notch 256 and 258 at one end and at the back wall top edge 225. It is to be appreciated that line segment 232 terminates at the back wall top edge 225 in the package's assembled state as will become more clear below. Front wall 204, side walls 208 and 210, and back wall 206 share a common bottom boundary at scored fold line 226 extending across the full width of blank 202 as illustrated in FIG. 12.
Front wall 204 terminates, at top edge 238 which meets the left and right end wall top edge segments 230 and 232 forming notches 256 and 258 therebetween as best illustrated in FIGS. 12 and 9. Front wall top edge 238 forms a tongue 228 with respect to imaginary line 222 extending between the bottom of notches 256 and 258.
Extending downward from common fold line 226 are bottom panels 250, 270, 290, and 295. Bottom panels 250, 270, 290, and 295 generally comprise the typical elements of an automatic folding bottom known within the industry as an automatic bottom.
Bottom panel 250 generally comprises a main portion 252 having a straight line edge 254 offset at a slight angle A from the extended fold line 214 as illustrated in FIG. 12. An opposing edge 260 is angularly offset from extended fold line 216 by angle B as illustrated in FIG. 12. Folding tab 258 extends outward from the main portion 252 at a right angle to edge 255 and is separated from portion 252 by scored fold line 260 representing the extended straight edge 255. The side edges 262 and 264, of tab 258, extend outward from edge 255 at right angles thereto and terminate at vertically extending edge 267. Extending from edge 254 to side edge 262, of tab 250, is a curved caming edge 266 and straight edge 268.
Bottom panel 270 is identical in configuration to bottom panel 250. Therefore, element numbers 252, 254, 255, 258, 260, 262, 264 266, 267 and 268 are also identical to, and correspond to, element numbers 272, 274, 276, 278, 280, 282, 284, 286, 287 and 288 respectively.
Bottom panel 290 generally comprises a trapezoidal configuration attached to side panel 210 at fold line 226. Converging, and opposing, side edges 291 and 292 terminate at horizontal edge 294. Similar to bottom panels 250 and 270, bottom panels 290 and 295 are identical with element numbers 291, 292, and 294 corresponding to element numbers 296, 295, and 298 respectively.
To assemble blank 202 into a flat, expandable perform illustrated in FIGS. 16A and 16B, bottom panels 250, 270, 295, and 290 are first folded upward 180 degrees, as indicated by the arrows in FIG. 12, whereby the bottom panels overlie panels 206, 204, 208, and 210 respectively as illustrated in FIG. 13. Tabs 258 and 278 are then folded downward 180 degrees, as indicated by the arrows in FIG. 13, about fold lines 260 and 280, so as to overlie the main portion 252 of bottom panels 250 and 270 respectively as illustrated in FIG. 14. A suitable adhesive 261 and 281 is applied to tabs 258 and 278 respectively. Tab 258, with adhesive 261 thereon, is folded 180 degrees, about fold line 216, as indicated by the arrow in FIG. 14, so as to over lie side panel 208 and a portion of front panel 204 as illustrated in FIG. 15. It is to be noted that upon making this fold, tab 258 becomes adhered to bottom panel 295 by adhesive line 261. An adhesive line 213 is then applied to glue tab 212 and side panel 210 is folded 180 degrees about fold line 220, as indicated by the arrow in FIG. 15, whereby adhesive 213 adheres side panel 210 to glue tab 212 and bottom panel 290 is adhered to tab 278 by adhesive 281 producing the final flat perform 240 as illustrated in FIG. 16A. FIG. 16B illustrates the perform 240, as illustrated in FIG. 16A flipped over 180 degrees thereby illustrating a front view of the flat final perform 240.
Referring now to FIGS. 17 and 18, two identical, open ended, fast food packages, as illustrated in FIG. 9, and identified as 200L and 200R, are illustrated as being assembled (package 200L telescoping into package 200R) to form a composite, enclosed, fast food package 300 illustrated in FIG. 18.
To form enclosed package 300 the left and right corners 283L and 285L, of package 200L are telescoped inside of right and left corners 283R and 285R, respectively and pushed together as indicated by the arrows in FIG. 17. As the gap between tongue 238L and 238R is closed, tongue 238L will override tongue 238R until notches 258L and 256R, on both sides of package 200L and 200R, interlockingly engage each other thereby forming enclosed package 300 as illustrated in FIG. 18.
Having described the preferred embodiments of the present invention, and several of its benefits and advantages, it will be understood by those of ordinary skill in the art that the foregoing description is merely for the purpose of illustration and that numerous substitutions, rearrangements, and modifications may be made in the invention without departing from the scope and spirit of the appended claims. | The present invention relates to a modular food package particularly suitable for use in the fast food industry, and more particularly to a modular package that can be used as a stand alone, open ended, scoop type, package suitable for containing food items, such as french fries, potato cakes, cookies, pies, and such, or two identical units may be combined to create a completely enclosed, and interlocking, package for a sandwich or other appropriate food items. | 1 |
FIELD OF THE INVENTION
The present invention pertains to the prophylaxis and treatment of disease caused by feline immunodeficiency virus (FIV), using genetically altered FIV virions. Specifically, a portion of the p10 gene, which encodes a protein responsible for packaging of the RNA into the virion, has been deleted. The resulting virions are produced in appropriate host cell lines and used to make vaccines comprising whole killed virions which do not comprise viral RNA.
BACKGROUND OF THE INVENTION
Feline immunodeficiency virus (FIV) infection is a significant health problem for domestic cats around the world. As in its human counterpart, infection with FIV causes a progressive disruption in immune function. In the acute phase of infection, the virus causes transient illness associated with symptoms such as lymphadenopathy, pyrexia, and neutropenia. Subsequently, an infected animal enters an asymptomatic phase of 1-2 years before clinical manifestations of immune deficiency become apparent, after which the mean survival time is usually less than one year.
FIV is a typical retrovirus that contains a single-stranded polyadenylated RNA genome, internal structural proteins derived from the gag gene product, and a lipid envelope containing membrane proteins derived from the env gene product (Bendinelli et al., Clin.Microbiol.Rev. 8:87, 1995). The gag gene is translated into a primary product of about 50 kDa that is subsequently cleaved by a viral protease into the matrix (p15), capsid (p25), and nucleocapsid (p10) proteins. The start and the end for each cleavage product of the GAG polyprotein are indicated in FIGS. 2A-2E underneath the open reading frame. The env gene yields a primary translation product of 75-80 kDa (unglycosylated molecular weight); in infected cells, the precursor has an apparent molecular weight of 145-150 kDa due to N-linked glycosylation. The env precursor is cleaved in the Golgi apparatus into the SU and TM proteins (also designated gp95 and gp40, respectively).
As discussed above, the gag gene of the feline immunodeficiency virus (FIV) is initially translated as a precursor polyprotein which is cleaved to yield the functionally mature matrix protein, capsid protein and nucleocapsid protein making up the core of virus (Elder et al., J. Virol. 67: 1869-76, 1993). The pot gene overlaps the gag gene by 112 nucleotides, and is in a −1 reading frame with respect to that of the gag gene. Thus, the gene is translated as a Gag-Pol fusion protein produced by ribosome frameshifting. The overlapping region contains frameshift signals, GGGAAAC and GGAGAAAC, located at the 3′ end of the gag gene (Morikawa et al., Virol. 186: 389-97, 1992).
The nucleocapsid protein, or p10, is a small basic protein, which is associated with the genomic RNA and may be required for viral RNA packaging (Egberink et al. J. Gen. Virol. 71: 739-743, 1990; Steinman et al., J. Gen. Virol. 71: 701-06, 1990). The p10 protein contains two cysteine arrays each consisting of 14 amino acid residues with the sequence C—X 2 —C—X 4 —H—X 4 —C (where X represents any amino acid and the subscript is the number of residues). Genetic studies with other retroviruses have shown that these two cysteine arrays are essential for viral RNA packaging (Rein et al., J. Virol. 68: 6124-29, 1994; Meric et al., J. Virol. 62: 3328-33; Gorelick et al., Proc. Natl. Acad. Sci. USA 85:8420-24, 1988). Therefore, deletion of these two cysteine arrays should, in theory, generate FIV virus particles which contains all viral proteins, but no viral genomic RNA. These FIV viral particles should be non-infectious and could be used to effect efficacious immune protection in vaccinated cats.
Most vaccines against FIV have failed to induce protective immunity. Ineffective vaccines have involved inactivated whole virus, fixed infected cells, recombinant CA and SU proteins, and a synthetic peptide corresponding to the V3 region of SU. In some cases, the vaccine actually enhanced infection after challenge. In one system, vaccination with paraformaldehyde-fixed virus or infected cells resulted in protective immunity (Yamamoto et al., J. Virol. 67:601, 1993), but application of this approach by others was unsuccessful (Hosie et al., in Abstracts of the International Symposium on Feline Retrovirus Research, 1993, page 50).
Thus, there is a need in the art for an effective whole killed virion vaccine against FIV.
SUMMARY OF THE INVENTION
The present invention pertains to the prevention or lessening of disease in cats caused by Feline Immunodeficiency Virus (FIV). Prevention or lessening of disease is understood to mean the amelioration of any symptoms, including immune system disruptions, that result from FIV infection.
The invention provides for a plasmid which encodes the FIV genome where said genome has had a portion of the gag gene, specifically the p10 (nucleocapsid) coding region, or a portion thereof, deleted. This deletion prevents the production of functional or whole p10 protein, which in turn, prevents the packaging of RNA into virions produced from transfection of this plasmid into an appropriate host cell, resulting in virions which do not contain RNA. Such virions will be described as “empty” virions. The invention also encompasses host cells transformed with the plasmid which produce the empty virions, and the empty virions themselves.
In another embodiment, the invention encompasses vaccines that comprise one or more empty virions described above, with a pharmaceutically acceptable carrier or diluent and a pharmaceutically acceptable adjuvant.
In yet another aspect, the invention provides methods for preventing or lessening disease caused by FIV, which is carried out by administering to a feline in need of such treatment the vaccines described above.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1A-1C are graphic illustration of the cloning strategy for creating FIV with deletion of p10.
FIGS. 2A-2E shows the DNA sequence of the gag gene of FIV SEQ ID. NO. 5, with the delineations of the coding sequence for the various proteolytic products indicated. The double underlined DNA sequence is deleted in a preferred embodiment of the present invention. The gag-pol frameshift start site is indicated by single underlining.
FIGS. 3A-3B show the protein sequences for the translation products of the gag gene of FIV, including both the primary SEQ ID. NO. 6 and secondary SEQ ID. NO. 7 open reading frames. The double underlined amino acids are not encoded by a preferred embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
All patents, patent applications, and references cited herein are hereby incorporated by reference in their entirety. In the case of inconsistencies, the present disclosure, including definitions, will control.
The vaccine of the present invention may be prepared by creating a recombinant FIV carrying a deletion of the p10 gene, or a portion thereof, encoding a portion of the gag protein of Feline Immunodeficiency Virus (FIV). The cloning scheme employed to produce the deleted virus eliminates 39 codons which include the two cysteine arrays within the p10 gene without disrupting either the gag gene open reading frame or the gag-pol frameshifting as occurs in the wild type virus-infected cells. The two cysteine arrays are highlighted in FIGS. 2A-2E, where cysteine array 1 encompasses nucleotides 1129 to 1170 and cysteine array 2 encompasses nucleotides 1186 to 1227. The thirty nine codons and amino acids which are deleted are double underlined in FIGS. 2 and 3. The deletion does not disrupt the original p10 open reading frame. The deletion also does not alter the gag-pol frameshift start site and frameshift signal. Therefore, in theory, the frequency of gag-pol frameshifting at nucleotide 1242 should not be affected by the deletion of the 39 codons preceding the gag-pol frameshift start site. FIGS. 2A-2E indicate the gag-pol frameshift start site by single underlining. FIGS. 2A-2E indicate the 5′ end of the POL polyprotein underneath the p10 open reading frame, while FIGS. 3A-3B list the amino acid sequence of p10 and the frameshifted POL protein.
The process for constructing the p10 deletion vaccine is outlined as follows. A plasmid construct is made which deletes a portion of the p10 encoding gene sequences using PCR-mediated mutagenesis. The construct is designed to not delete any of the 112 nucleotides (1243 to 1353) which overlap the gag and pol genes and to not eliminate the frameshift signal which is necessary for pol transcription. Once constructed, the plasmid is transfected into an appropriate host cell, such as mammalian cells, and the transformed cells are screened for non-infectious virus production. Cells which prove to produce non-infectious (presumably empty) virions are used to produce high levels of virus particles, which are isolated from the cell culture medium.
Although this particular construct and method are effective in producing empty virions, i.e., those which do not contain RNA, one of ordinary skill in the art would recognize alternative well-known methods of achieving the same goal. For example, the deletion need not eliminate the whole p10 encoding sequence, only enough sequence for the function of the protein to be eliminated. One representative example of this approach would be deletion of only one of the two cysteine arrays. Further, fragments of sequence need not be deleted. Any genetic alteration, i.e., site-directed mutagenesis of cysteines within the array, using methods well known in the art can be employed to construct a FIV genome which encodes empty virions. Thus, well-known variants of the genetic alterations presently employed which result in genomes which encode empty virions are contemplated to be within the scope of the present invention.
The isolated virus may be stored after concentration at 4° C. or frozen (−50° C. or colder) or lyophilized until the time of use. Compounds such as NZ-amine, dextrose, gelatin or others designed to stabilize the virus during freezing and lyophilization may be added. The virus may be concentrated using commercially available equipment. To produce the vaccine, isolated particles can be chemically treated to ensure lack of infectivity, that is, inactivated and mixed with an adjuvant(s).
Typically, the concentration of virus in the vaccine formulation will be a minimum of 10 6.0 virus particles per dose, but will typically be in the range of 10 6.0 to 10 8.0 virus particles per dose. At the time of vaccination, the virus is thawed (if frozen) or reconstituted (if lyophilized) with a physiologically-acceptable carrier such as deionized water, saline, phosphate buffered saline, or the like. An additional optional component of the present vaccine is a pharmaceutically acceptable adjuvant. Non-limiting examples of suitable adjuvants include squalane and squalene (or other oils of animal origin); block copolymers such as Pluronic® (L121) Saponin; detergents such as Tween®-80; Quil® A, mineral oils such as Drakeol® or Marcol®, vegetable oils such as peanut oil; Corynebacterium-derived adjuvants such as corynebacterium parvum; Propionibacterium-derived adjuvants such as Propionibacterium acne; Mycobacterium bovis (Bacillus Calmette and Guerinn, or BCG); interleukins such as interleukin 2 and interleukin-12; monokines such as interleukin 1; tumor necrosis factor; interferons such as gamma interferon; combinations such as saponin-aluminum hydroxide or Quil®-A aluminum hydroxide; liposomes; iscom adjuvant; mycobacterial cell wall extract; synthetic glycopeptides such as muramyl dipeptides or other derivatives; Avridine; Lipid A; dextran sulfate; DEAE-Dextran or DEAE-Dextran with aluminum phosphate; carboxypolymethylene, such as Carbopol®; ethylene malelic anhydride (EMA); acrylic copolymer emulsions such as Neocryl® A640 (e.g. U.S. Pat. No. 5,047,238); vaccinia or animal poxvirus proteins; subviral particle adjuvants such as orbivirus; cholera toxin; dimethyldiocledecylammonium bromide; or mixtures thereof.
Individual genetically altered virions may be mixed together for vaccination. Furthermore, the virus may be mixed with additional inactivated or attenuated viruses, bacteria, or fungi such as feline leukemia virus, feline panleukopenia virus, feline rhinotracheitis virus, feline calicivirus, feline infectious peritonitis virus, feline Chlamydia psittaci, Microsporum canis, or others. In addition, antigens from the above-cited organisms may be incorporated into combination vaccines. These antigens may be purified from natural sources or from recombinant expression systems, or may comprise individual subunits of the antigen or synthetic peptides derived therefrom.
The produced vaccine can be administered to cats by subcutaneous, intramuscular, oral, intradennal, or intranasal routes. The number of injections and their temporal spacing may be varied. One to three vaccinations administered at intervals of one to three weeks are usually effective.
The efficacy of the vaccines of the present invention is assessed by the following methods. At about one month after the final vaccination, vaccinates and controls are each challenged with 3-20 cat ID 50 units, preferably 5 cat ID 50 units of FIV, preferably the NCSU-1 isolate (ATCC accession number VR 2333). Whole blood is obtained from the animals immediately before challenge, and at intervals after challenge, for measurement of a) viremia and b) relative amounts of CD4 and CD8 lymphocytes.
Viremia is measured by isolating mononuclear cells from the blood, and co-culturing the cells with mononuclear cells from uninfected animals. After 7 days of culture, the culture supernatants are tested for FIV by enzyme-linked immunoassay (See Example 3 below).
The ratio of CD4 to CD8 lymphocytes in the circulation of vaccinates and controls is taken as a measure of immune function. Typically, FIV infection causes an inversion of the normal CD4:CD8 ratio of about 1.5-4 to a pathological ratio of about 0.5-1. The titers of CD4 and CD8 lymphocytes are measured by flow cytometry using specific antibodies (see Example 3 below).
Another measure of immune function is to challenge vaccinates and controls with Toxoplasma gondii at 6 months -12 months after the final vaccination. Normally, the severity of T. gondii -induced disease symptoms is considerably exacerbated in FIV-infected cats relative to uninfected cats. The severity of the T. gondii effect is determined by scoring ocular discharge, nasal discharge, dyspnea, and fever.
It will be understood that amelioration of any of the symptoms of FIV infection is a desirable clinical goal. This includes a lessening of the dosage of medication used to treat FIV-induced symptoms.
The following examples are intended to illustrate the present invention without limitation thereof.
Example 1
Preparation of p10 Deleted FIV Strain
1. Isolation of Parental DNA
Purified lambda DNA containing the full length proviral sequence for the NCSU-1 isolate is prepared with Wizard Lambda Preps DNA Purification System (Promega Corporation, Madison, Wis.) and is used as the parental DNA for constructing deletion mutants. DNA digestion, ligation and other molecular techniques are performed as described (Sambrook et al., Molecular Cloning: A Laboratory Manual, 2nd ed. Cold Spring Harbor Laboratory, 1989).
B. Preparation of FIV-Left Plasmid
Purified lambda DNA is digested with SalI to release the 11-kb insert DNA containing the full length FIV proviral sequence. The insert DNA is purified by the glass bead method using the GENECLEAN II kit from BIO 101, Inc. and digested with NcoI which cuts only once on the FIV genome, producing a 2.9 kb SalI-NcoI fragment, designated as fragment A, and a 8.1 kb NcoI-SalI fragment, designated as fragment B.
Fragment A is purified by glass bead method as above and subcloned into plasmid vector pGEM 5Zf(t) (Promega Corp., Madison, Wis.) to generate plasmid pFIV-left. The plasmid pFIV-left contains the left portion of the viral genome including the LTR, p15, p25 and p10 gene.
C. Deletion of p10 Sequence
Deletion of the two cysteine arrays within the p10 gene is facilitated by PCR-mediated mutagenesis using high-fidelity Pwo DNA polymerase according to the manufacturer's manual (Boehringer Mannheim, USA, Indianapolis, Ind.). The plasmid pFIV-left is used as the initial template for PCR reaction. SP6 primer and primer A are used to amplify 2.2-kb fragment C with sequence which ends at nucleotide 1124. The SP6 primer:
5′-TTAGGTGACACTATAGAATACTCAA-3′ SEQ ID. NO. 1
anneals to the vector sequence upstream the SalI site. Primer A:
5′-GGTCCTGATCCTTTTGATTGCACTA-3′ SEQ ID. NO. 2
anneals to the FIV sequence, nucleotides 1100 to 1124.
Primer B and T7 primer are used to amplify 0.6-kb fragment D which starts at nucleotide 1242. The primer:
5′-AAAGAATTCGGGAAACTGGAAGGCGG-3′ SEQ ID. NO. 3
anneals within the gag p10 gene, nucleotides 1242 to 1267. The T7 primer:
5′-TAATACGACTCACTATAGGGCGAATTG-3′ SEQ ID. NO. 4
anneals to the vector sequence downstream from the NcoI site.
The location for each GAG-specific primer is highlighted in FIGS. 2A-2E.
Fragment C and fragment D are purified as above, ligated and the ligation products are used as the template to amplify a 2.8-kb fragment using SP6 primer and T7 primer. The 2.8-kb fragment generated is purified as above and digested with SalI and NcoI to generate fragment E. Fragment E is identical to fragment A except the sequence for the segment spanning the two cysteine arrays is deleted, i.e. the sequence spanning nucleotides 1125 to 1241 is removed (see FIG. 1 ).
C. Construction of FIV delta p10 Plasmid
Fragment E and fragment B generated are purified as above. Then fragment E and fragment B are combined and cloned into the SalI site of the gene targeting vector pMC1neo Poly A (Stratagene, LaJolla, Calf.; Thomas, K. R., and Capecchi, M. R., Cell 51: 503-21, 1987), generating plasmid pFIV delta p10. The plasmid pFIV delta p10 contains the entire FIV genome with internal deletion within the p10 gene in addition to the neomycin resistance gene present on the gene targeting vector.
D. Production of Virions
Stable transfectants are obtained by transfecting the plasmid pFIV delta p10 into Vero cells (ATCC CCL 81), Crandell feline kidney cells (ATCC CCL 94) or AH927 feline embryonic fibroblast cells (Overbaugh et al., Virol. 188: 558-569, 1992) and selection by G418 by using cationic liposome-mediated transfection with the LIPOFECtamine® reagent and G418 (Genticin) according to the manufacturer's instruction (Life Technologies, Inc., Gaithersburg, Md.). Cultures of G418-resistant cells are tested for virus particle production by a) assaying the viral particle-associated reverse transcriptase activity; b) complementation plaque assay as described (Rein et al., J. Virol. 29: 494-500, 1979) to determine if the virus particles are able to initiate single cycle of infection; c) Western blotting using antiserum against the major core protein p25 (IDEXX, USA, Portland, Me.) to examine the integrity of the viral proteins; and d) direct examination of viral particles by electron microscopy.
The virus particles released from the stably transfected cells are to be examined for a) absence of viral RNA and DNA by RT-PCR and DNA PCR and b) absence of infectivity by the standard validated infectivity assays.
EXAMPLE 2
Preparation of Whole Killed Empty FIV Vaccines
Stably-transfected cells which produce non-infectious viral particles are grown on microcarriers in bioreactors or in roller bottles. Culture fluids are harvested at the time or multiple times when the viral particles reach high levels as determined by electron microscopy and/or the feline immunodeficiency virus antigen test kit (IDEXX, USA, Portland, Me.). The viral particles are inactivated by treatment with formalin or with binary ethylenimine, according to standard protocols well known in the art. Following inactivation, the viral particles are concentrated 10 to 50 fold with the hollow fiber procedure using a cut-off at molecular weight of 10,000 to 100,000 daltons. For preparing the vaccines, the concentrated fluids containing viral particles are mixed with immunologenically stimulating adjuvant, for example, ethylene maleic anhydride (EMA) 31, neocryl, MVP emulsigen, mineral oil, or adjuvant A or combination of several immunologenically stimulating adjuvants. Adjuvant A is an adjuvant comprising a block copolymer, such as a polyoxypropylene-polyoxyethylene (POP-POE) block copolymer, preferably Pluronic® L121 (e.g. U.S. Pat. No. 4,772,466), and an organic component, such as a metabolizable oil, e.g. an unsaturated turpin hydrocarbon, preferably squalane (2,6,10,15,19,23-hexamethyltetracosane) or squalene.
In this adjuvant mixture, the block copolymer, organic oil, and surfactant may be present in amounts ranging from about 10 to about 40 ml/L, about 20 to about 80 ml/L, and about 1.5 to about 6.5 ml/L, respectively. In a preferred embodiment of the stock adjuvant, the organic component is squalane present in an amount of about 40 mL/L, the surfactant is polyoxyethylenesorbitan monooleate (Tween®-80) present in an amount of about 3.2 ml/L, and the POP-POE block copolymer is Pluronic® L121 present in an amount of about 20 ml/L. Pluronic® L121 is a liquid copolymer at 15-40 C, where the polyoxypropylene (POP) component has a molecular weight of 3250 to 4000 and the polyoxyethylene (POE) component comprises about 10-20%, preferably 10%, of the total molecule.
Non-limiting examples of other suitable adjuvants include squalane and squalene (or other oils of animal origin); block copolymers such as Pluronic® (L121) Saponin; detergents such as Tween®-80; Quil® A, mineral oils such as Drakeol® or Marcol®, vegetable oils such as peanut oil; Corynebacterium-derived adjuvants such as corynebacterium parvum; Propionibacterium-derived adjuvants such as Propionibacterium acne; Mycobacterium bovis (Bacillus Calmette and Guerinn, or BCG); interleukins such as interleukin 2 and interleukin-12; monokines such as interleukin 1; tumor necrosis factor, interferons such as gamma interferon; combinations such as saponin-aluminum hydroxide or Quil® -A aluminum hydroxide; liposomes; iscom adjuvant; mycobacterial cell wall extract; synthetic glycopeptides such as muramyl dipeptides or other derivatives; Avridine; Lipid A; dextran sulfate; DEAE-Dextran or DEAE-Dextran with aluminum phosphate; carboxypolymethylene, such as Carbopol®; EMA; acrylic copolymer emulsions such as Neocryl® A640 (e.g. U.S. Pat. No. 5,047,238); vaccinia or animal poxvirus proteins; subviral particle adjuvants such as orbivirus; cholera toxin; dimethyldiocledecylammonium bromide; or mixtures thereof. The composition may also include a non-ionic detergent or surfactant, preferably a polyoxyethylene sorbitan monooleate such as a Tween® detergent, most preferably Tween®-80, i.e. polyoxyethylene (20) sorbitan monooleate.
Typically, 1 ml dose contains at least 10 6 viral particles, as determined by electron microscopy or the feline immunodeficiency virus antigen test kit (IDEXX, USA, Portland, Me.).
Example 3
Test of Efficacy of Whole Killed Empty FIV Vaccines
A. Vaccination
Cats of age 8 weeks or greater are injected subcutaneously or intramascularly with the vaccine prepared above. Each cat receives two injections of vaccine at a 2-4 week interval. Two to six weeks following vaccination, the vaccinated cats and non-vaccinated cats are challenged by inoculating with 5 cat ID 50 of feline immunodeficiency virus (NCSU-1 isolate (ATCC VR 2333) and some other isolates). Antibody response to vaccination is measured by ELISA using a neutralizing peptide within the immunodominant region (V3) of the FIV envelope protein (Lombardi et al., J. Virol. 67:4742-49, 1993). Viral replication following challenging is monitored biweekly by a) determining the levels of FIV RNA or/+ proviral DNA with RT-PCR and DNA PCR; and/or b) by co-cultivation for presence of infectious virus particles.
1. Detection of Viremia
a. PCR Detection of FIV proviral DNA
Mononuclear cells were isolated from whole blood using Percoll™ (Pharmacia Biotech, Piscataway N.J.) gradients. 5×10 5 cells were lysed and {fraction (1/10)}th of the lysate used in a polymerase chain reaction assay with oligonucleotide primers specific to the gag gene of FIV (TL Wasmoen et al. Vet. Immun. Immunopath. 35: 83-93, 1992) or the equivalent. FIV amplified DNA was detected by agarose gel electrophoresis and ethidium bromide staining or by enzyme linked oligonucleotide assays.
b. Tissue Culture Isolation of FIV
Culture isolate of FIV is performed as described previously (Wasmoen et al., Vet. Immuno. Immunopath. 35:83-93, 1992). Mononuclear cells are isolated from whole blood using Percol™ (Pharmacia Biotech, Piscataway N.J.) gradients. 5×10 5 cells from FIV-challenged cats were cultured with 1×10 6 mononuclear cells isolated from uninfected cats. Cultures are fed with RPMI media every 7 days and supernatant tested for the presence of FIV by an enzyme-linked immunosorbent assay (ELISA) that detects FIV p25 antigen (Petcheck ELISA, IDEXX, Portland, Me.). Alternatively, plasma can be used as the source of infectious virus.
2. Lymphocyte Subsets
Leukocytes are isolated from whole blood using Histopaque™ (Sigma Chemical Company, St. Louis Mo.) and lymphocyte subsets quantitated by staining the cells with antibodies specific to CD4 (monoclonal antibody CAT30A), CD8 (monoclonal antibody FLSM 3.357), pan T lymphocytes (monoclonal antibody FLSM 1.572) or B lymphocytes (anti-cat IgG) followed by FACS analysis. These monoclonal antibodies are described elsewhere (M.B. Tompkins et al. Vet. Immunol. Immunopathol. 26:305-317, 1990) and the flow cytometry procedure is the same as previously described (R.V. English et al. J. Infect. Dis. 170:543-552, 1994). CD4:CD8 ratios are calculated.
B. Toxoplasma gondii Challenge
Eight to twelve weeks following challenge with FIV, the cats are inoculated with 10,000 to 50,000 tacheozoites of Toxoplasma gondii. Tacheozoites of the ME49 strain of T. gondii that were frozen in 10% glycerol or oocyts were inoculated intraperitoneally into Swiss mice (Charles Rivers Laboratories) and serially passed in mice according to published procedures (Davidson et al., Am. J. Pathol. 143:1486, 1993). Tacheozoites harvested from peritoneal fluids of mice were enumerated using a hemacytometer. Cats were tranquilized using ketamine hydrochloride and inoculated with 50,000 fresh tacheozoites into the right common carotid artery that had been surgically isolated. Inoculation with Toxoplasma in this dosage generally causes mortality in up to 50% of cats which are FIV-infected and have not been vaccinated. Following Toxoplasma challenge, cats are monitored weekly for signs of clinical disease including ocular discharge, nasal discharge, dyspnea, fever, depression, and weight loss for 3 days prior to and up to 48 days following T. gondii inoculation.
Clinical signs follow T. gondii challenge were scored as follows:
Clinical Sign
Score
Fever
103.0 to
1 point per day
103.9° F.
104.0 to
2 points per day
104.9° F.
≧105.0° F.
3 points per day
(Temperatures were not scored until ≧1° F. above baseline.)
Depression/Lethargy
1 point per day
Dehydration
2 points per day
Nasal Discharge
1 point per day
Ocular Discharge
1 point per day
Respiratory Distress:
Tachypnea
2 points per day
Dyspnea
4 points per day
It is expected that the vaccine prepared as described above will significantly reduce the appearance of clinical signs and mortality due to Toxoplasma infection.
7
25 base pairs
nucleic acid
single
linear
DNA (genomic)
Bacteriophage SP6
SP6 primer
bp
1
TTAGGTGACA CTATAGAATA CTCAA 25
25 base pairs
nucleic acid
single
linear
DNA (genomic)
feline immunodeficiency virus
NCSU-1
1100-1124
bp
2
GGTCCTGATC CTTTTGATTG CACTA 25
26 base pairs
nucleic acid
single
linear
DNA (genomic)
feline immunodeficiency virus
NCSU-1
1242-1267
bp
3
AAAGAATTCG GGAAACTGGA AGGCGG 26
27 base pairs
nucleic acid
single
linear
DNA (genomic)
Bacteriophage T7
T7 primer
bp
4
TAATACGACT CACTATAGGG CGAATTG 27
1353 base pairs
nucleic acid
single
linear
DNA (genomic)
feline immunodeficiency virus
NCSU-1
1-1353
bp
5
ATGGGGAATG GACAGGGGCG AGATTGGAAA ATGGCCATTA AGAGATGTAG TAATGCTGCT 60
GTAGGAGTAG GGGGGAAGAG TAAAAAATTT GGGGAAGGGA ATTTCAGATG GGCCATTAGA 120
ATGGCTAATG TATCTACAGG ACGAGAACCT GGTGATATAC CAGAGACTTT AGATCAACTA 180
AGGTTGGTTA TTTGCGATTT ACAAGAAAGA AGAAAAAAAT TTGGATCTTG CAAAGAAATT 240
GATAAGGCAA TTGTTACATT AAAAGTCTTT GCGGCAGTAG GACTTTTAAA TATGACAGTG 300
TCTTCTGCTG CTGCAGCTGA AAATATGTTC ACTCAGATGG GATTAGACAC TAGACCATCT 360
ATGAAAGAAG CAGGAGGAAA AGAGGAAGGC CCTCCACAGG CATTTCCTAT TCAAACAGTA 420
AATGGAGTAC CACAATATGT AGCACTTGAC CCAAAAATGG TGTCCATTTT TATGGAAAAG 480
GCAAGAGAAG GATTAGGAGG TGAGGAAGTT CAGCTATGGT TCACTGCCTT CTCTGCAAAT 540
TTAACACCTA CTGACATGGC CACATTAATA ATGGCCGCAC CAGGGTGCGC TGCAGATAAA 600
GAAATATTGG ATGAAAGCTT AAAGCAACTT ACTGCAGGAT ATGATCGTAC ACATCCCCCT 660
GATGCTCCCA GACCATTACC CTATTTTACT GCAGCAGAAA TTATGGGTAT TGGATTTACT 720
CAAGAACAAC AAGCAGAAGC AAGATTTGCA CCAGCTAGGA TGCAGTGTAG AGCATGGTAT 780
CTCGAGGGAC TAGGAAAATT GGGCGCCATA AAAGCTAAGT CTCCTCGAGC TGTGCAGTTA 840
AGACAAGGAG CTAAGGAAGA TTATTCATCC TTTATTGACA GATTGTTTGC CCAAATAGAT 900
CAAGAACAAA ATACAGCTGA AGTTAAGTTA TATTTAAAAC AGTCATTAAG CATGGCTAAT 960
GCTAATGCAG AATGTAAAAA GCCAATGACC CACCTTAAGC CAGAAAGTAC CCTAGAAGAA 1020
AAGTTGAGAG CTTGTCAAGA AATAGGCTCA CCAGGATATA AAATGCAACT CTTGGCAGAA 1080
GCTCTTACAA AAGTTCAAGT AGTGCAATCA AAAGGATCAG GACCAGTGTG TTTTAATTGT 1140
AAAAAACCAG GACATCTAGC AAGACAATGT AGAGAAGTGA GAAAATGTAA TAAATGTGGA 1200
AAACCTGGTC ATGTAGCTGC CAAATGTTGG CAAGGAAATA GAAAGAATTC GGGAAACTGG 1260
AAGGCGGGGC GAGCTGCAGC CCCAGTGAAT CAAGTGCAGC AAGCAGTAAT GCCATCTGCA 1320
CCTCCAATGG AGGAGAAACT ATTGGATTTA TAA 1353
450 amino acids
amino acid
single
linear
protein
feline immunodeficiency virus
NCSU-1
6
Met Gly Asn Gly Gln Gly Arg Asp Trp Lys Met Ala Ile Lys Arg Cys
1 5 10 15
Ser Asn Ala Ala Val Gly Val Gly Gly Lys Ser Lys Lys Phe Gly Glu
20 25 30
Gly Asn Phe Arg Trp Ala Ile Arg Met Ala Asn Val Ser Thr Gly Arg
35 40 45
Glu Pro Gly Asp Ile Pro Glu Thr Leu Asp Gln Leu Arg Leu Val Ile
50 55 60
Cys Asp Leu Gln Glu Arg Arg Lys Lys Phe Gly Ser Cys Lys Glu Ile
65 70 75 80
Asp Lys Ala Ile Val Thr Leu Lys Val Phe Ala Ala Val Gly Leu Leu
85 90 95
Asn Met Thr Val Ser Ser Ala Ala Ala Ala Glu Asn Met Phe Thr Gln
100 105 110
Met Gly Leu Asp Thr Arg Pro Ser Met Lys Glu Ala Gly Gly Lys Glu
115 120 125
Glu Gly Pro Pro Gln Ala Phe Pro Ile Gln Thr Val Asn Gly Val Pro
130 135 140
Gln Tyr Val Ala Leu Asp Pro Lys Met Val Ser Ile Phe Met Glu Lys
145 150 155 160
Ala Arg Glu Gly Leu Gly Gly Glu Glu Val Gln Leu Trp Phe Thr Ala
165 170 175
Phe Ser Ala Asn Leu Thr Pro Thr Asp Met Ala Thr Leu Ile Met Ala
180 185 190
Ala Pro Gly Cys Ala Ala Asp Lys Glu Ile Leu Asp Glu Ser Leu Lys
195 200 205
Gln Leu Thr Ala Gly Tyr Asp Arg Thr His Pro Pro Asp Ala Pro Arg
210 215 220
Pro Leu Pro Tyr Phe Thr Ala Ala Glu Ile Met Gly Ile Gly Phe Thr
225 230 235 240
Gln Glu Gln Gln Ala Glu Ala Arg Phe Ala Pro Ala Arg Met Gln Cys
245 250 255
Arg Ala Trp Tyr Leu Glu Gly Leu Gly Lys Leu Gly Ala Ile Lys Ala
260 265 270
Lys Ser Pro Arg Ala Val Gln Leu Arg Gln Gly Ala Lys Glu Asp Tyr
275 280 285
Ser Ser Phe Ile Asp Arg Leu Phe Ala Gln Ile Asp Gln Glu Gln Asn
290 295 300
Thr Ala Glu Val Lys Leu Tyr Leu Lys Gln Ser Leu Ser Met Ala Asn
305 310 315 320
Ala Asn Ala Glu Cys Lys Lys Pro Met Thr His Leu Lys Pro Glu Ser
325 330 335
Thr Leu Glu Glu Lys Leu Arg Ala Cys Gln Glu Ile Gly Ser Pro Gly
340 345 350
Tyr Lys Met Gln Leu Leu Ala Glu Ala Leu Thr Lys Val Gln Val Val
355 360 365
Gln Ser Lys Gly Ser Gly Pro Val Cys Phe Asn Cys Lys Lys Pro Gly
370 375 380
His Leu Ala Arg Gln Cys Arg Glu Val Arg Lys Cys Asn Lys Cys Gly
385 390 395 400
Lys Pro Gly His Val Ala Ala Lys Cys Trp Gln Gly Asn Arg Lys Asn
405 410 415
Ser Gly Asn Trp Lys Ala Gly Arg Ala Ala Ala Pro Val Asn Gln Val
420 425 430
Gln Gln Ala Val Met Pro Ser Ala Pro Pro Met Glu Glu Lys Leu Leu
435 440 445
Asp Leu
37 amino acids
amino acid
single
linear
peptide
N-terminal
feline immunodeficiency virus
NCSU-1
7
Lys Glu Phe Gly Lys Leu Glu Gly Gly Ala Ser Cys Ser Pro Ser Glu
1 5 10 15
Ser Ser Ala Ala Ser Ser Asn Ala Ile Cys Thr Ser Asn Gly Gly Glu
20 25 30
Thr Ile Gly Phe Ile
35 | The present invention pertains to the prevention or lessening of disease in cats caused by Feline Immunodeficiency Virus (FIV). Prevention or lessening of disease is understood to mean the amelioration of any symptoms, including immune system disruptions, that result from FIV infection. The invention provides for a plasmid which encodes the FIV genome where said genome has had a portion of the gag gene, specifically the p10 (nucleocapsid) coding region, or a portion thereof, deleted. This deletion prevents the production of functional or whole p10 protein, which in turn, prevents the packaging of RNA into virions produced from transfection of this plasmid into an appropriate host cell, resulting in virions which do not contain RNA. Such virions will be described as “empty” virions. The invention also encompasses host cells transformed with the plasmid which produce the empty virions, and the empty virions themselves. In another embodiment, the invention encompasses vaccines that comprise one or more empty virions described above, with a pharmaceutically acceptable carrier or diluent and a pharmaceutically acceptable adjuvant. In yet another aspect, the invention provides methods for preventing or lessening disease caused by FIV, which is carried out by administering to a feline in need of such treatment the vaccines described above. | 0 |
[0001] The present invention relates to techniques for reducing noise introduced to a FM demodulator from a local oscillator signal generator.
[0002] More specifically, an aspect of the invention relates to a method and apparatus for removing an audible tone that may be present in the audio signal produced by an FM receiver, when the receiver LO has reference spurs, typically at the PLL reference frequency.
BACKGROUND
[0003] Despite the rise of digital radio, FM radio receivers are still very popular and are increasingly seen in mobile telephones and other electronic handheld devices such as MP3 players. The introduction of FM radio receivers into such devices has introduced a new set of noise problems which had not previously been a priority for FM designers, particularly with respect to stereo FM broadcasts, which is the dominant format used today.
[0004] In order to ensure that stereo broadcasts are compatible with mono receivers having just one speaker, stereo FM is encoded in a manner that allows a mono receiver to easily extract a channel which contains a mix of the left and right stereo channels. Stereo FM is encoded using two channels, one being the sum of the left and right stereo channels (L+R) and the other being the difference of the left and right channels (L-R). A mono receiver uses just the L+R channel for playback. A stereo receiver can add the L+R and L-R channels to obtain the left channel and subtract the L-R signal from the L+R signal to obtain the right channel.
[0005] As shown in FIG. 1 , when suitably demodulated, the main L+R channel occupies a frequency range of 30 Hz to 15 kHz. Sub-channel L-R is a double-sideband suppressed carrier (DSBSC) signal using the baseband range of 23 kHz to 53 kHz. A pilot tone is also present at 19 kHz and is used to allow the sub carrier to be demodulated with the correct phase. At the FM transmitter, a composite signal of the main channel, sub-channel and pilot tone can be used to modulate the carrier.
[0006] FIG. 2 shows a typical FM receiver arrangement. The FM signal is received from the FM transmitter via the antenna, amplified using a low noise amplifier (LNA) and then mixed with a local oscillator (LO) signal. The LO signal is generated using a phase locked loop (PLL). The LO signal is used to down convert the received signal. The down-conversion processes the received signal to create an intermediate frequency (IF) signal where the frequency spectrum of the wanted signal component is located at frequencies that are convenient for further processing. The IF signal is then filtered to remove unwanted noise, before it is demodulated by an FM demodulator. The resulting signal is then filtered to produce a separate L+R channel. The L-R channel is generated by translating the stereo sub-carrier to base-band, whereby its spectrum is ‘shifted’ in frequency by 38 kHz. This shift is performed by mixing the stereo sub-carrier with a 38 kHz signal using a mixing circuit.
[0007] The individual left and right channels are then generated by summing the L+R and L-R channels as described above. E.g. The L+R and L-R channels are summed to obtain the left channel and the L-R signal is subtracted from the L+R signal to obtain the right channel.
[0008] One problem with this system is a type of noise resulting from PLL ‘reference spurs’. The signal generated by a PLL usually has a number of spurious noise levels. The specification of a RF system making use of a PLL usually takes this into account. These spurious noise levels may occur for several different reasons. A ‘reference spur’ is so named as it results from feedthrough from the reference signal used by the PLL. The spurs are caused by imperfections in the PLL components, such as a mismatched propagation delay in the phase frequency detector, mismatches in the charge injection and current, and leakage current in the VCO tuning node. Consequently, as the PLL is unable to generate an output signal perfectly in phase with the reference signal, an oscillation of the phase of the generated signal occurs as the VCO continually corrects to bring the generated back or forward to match the reference signal. This oscillation has a frequency matching the reference frequency. Therefore, the resulting signal generated by the PLL has, not only an AM modulated component, but an FM modulated component.
[0009] Therefore, the reference spur is a sinusoidal phase modulation of the local oscillator signal at the frequency of F_ref (the reference frequency used for the PLL clock). In the FM receiver described above, when the received FM signal is mixed with the LO signal featuring the reference spur, a sinusoidal phase modulated noise signal at a frequency of F_ref is included in the resulting signal. When this signal is FM demodulated, a noise signal at frequency F_ref results. Where F_ref is within the band occupied by either the stereo main channel or sub-channel, this can result in audible noise in the fully demodulated FM stereo signal.
[0010] FIG. 3 shows an example of the reference spur noise problem described above. Many mobile phones currently include FM stereo broadcast receivers and supply to them a clock with a frequency of 32768 Hz. This clock frequency is commonly used in mobile phone architectures. Where the FM receiver incorporates a PLL that generates an LO signal for down-conversion, it is often convenient to use the 32768 Hz clock as a reference signal for the PLL. A 32768 Hz clock used as a reference signal for the PLL can create a 32768 Hz LO spur, resulting in a sinusoid of 32768 Hz being added to the stereo multiplex signal recovered in the receiver through FM demodulation. This unwanted 32768 Hz sinusoid lies within the 23 kHz-53 kHz band occupied by the stereo sub-carrier. The signal processing in the receiver includes translating the stereo sub-carrier to base-band, whereby its spectrum is ‘shifted’ in frequency by 38 kHz to produce the L-R signal. Once the FM signal has been fully demodulated, the unwanted sinusoid appears in the L-R signal at a frequency of 38000 Hz−32768 Hz=5232 Hz. The L-R signal is subsequently added to the L+R signal to produce stereo audio consisting of ‘left’ and ‘right’ signals. Hence the unwanted sinusoid is audible in the left and right channels at 5232 Hz.
[0011] Previous approaches to addressing this problem have involved refining the design of the voltage controlled oscillator (VCO) in the PLL to minimise the size of the reference spurs and so reduce the spurious audio noise. These techniques can require a great precision in the manufacture of the components and result in a higher per-unit cost.
[0012] What is needed is a method of reducing or eliminating the noise resulting from the reference spurs without the use of more expensive components.
[0013] According to a first aspect of the present invention there is provided an apparatus to reduce noise in a stereo FM broadcast received via an antenna, the apparatus comprising: a frequency translator configured to translate the received stereo FM broadcast to an intermediate carrier frequency, a demodulation unit configured to demodulate the translated FM signal so as to form left-plus-right and left-minus-right AM signals, a filter configured to form a filtered signal by filtering one of the AM signals, so as to suppress a sub-band of that signal containing unwanted tones, a summing unit for summing the filtered signal and the other of the left-plus-right and left-minus-right signals to produce a stereo audio signal.
[0014] According to a second aspect of the invention, there is provided a method of filtering noise from a stereo FM signal, the method comprising the steps of: demodulating an FM stereo broadcast signal into the left-plus-right and left-minus-right AM signals, filtering one of the AM signals, so as to suppress a sub-band of that signal containing unwanted tones, summing the filtered signal and the other of the left-plus-right and left-minus-right signals in such a manner as to produce a stereo audio signal.
[0015] Aspects of the present invention will now be described by way of example with reference to the accompanying drawing. In the drawings:
[0016] FIG. 1 shows the demodulated L+R, L-R and pilot tone channels of an FM broadcast.
[0017] FIG. 2 shows a typical FM receiver arrangement known in the art. FIG. 3 shows the demodulated FM broadcast of FIG. 1 with a noise component at 32768 Hz.
[0018] FIG. 4 shows an embodiment of the invention incorporated into a handheld device.
[0019] FIG. 5 shows an embodiment of the invention having a band bass filter applied to the L-R channel.
[0020] FIG. 6 shows another embodiment of the invention wherein the unwanted tone is filtered and then subtracted from the L-R channel.
[0021] FIG. 7 shows another embodiment of the invention wherein the unwanted tone is synthesised and then subtracted from the L-R channel.
[0022] FIG. 8 shows the demodulated FM broadcast of FIG. 1 with a unwanted noise tone residing in a band occupied by a component of the stereo multiplex signal other than the stereo sub-carrier,
[0023] FIG. 9 shows an example of a notch filter frequency response at 5232 Hz.
[0024] FIG. 10 shows the stereo separation of the output signal around the frequencies effected by the notch filter.
DESCRIPTION OF THE INVENTION
[0025] As shown in FIG. 4 , an aspect of the invention provides a mobile handset 200 having a subsystem 210 . Subsystem 210 includes reference frequency source 220 providing a reference signal 230 having a reference frequency. Reference signal 230 is used by Local Oscillator (LO) generator 240 to generate LO signal 250 . LO signal 250 is then used by FM demodulator 270 to translate an FM broadcast received using antenna 10 to an intermediate frequency for further processing by FM demodulator 270 .
[0026] FIG. 5 shows an antenna 10 for receiving the FM broadcast. The received signal is then amplified using low noise amplifier 30 . Local oscillator 40 comprises a phase locked loop (PLL) signal generator using reference frequency of reference signal 230 to generate a LO signal. The received and amplified FM signal is mixed with the LO signal to translate the received signal to an intermediate frequency (IF) more suitable for processing. IF filter 50 then filters unwanted noise from the IF signal. FM demodulator demodulates the FM IF signal and generates the full composite signal spectrum. A 38 kHz tone coherent with the stereo subcarrier is produced by sub-carrier recovery module 70 and mixed with the received stereo multiplex signal using mixer 80 to translate the stereo sub-carrier to baseband. The L-R and L+R channels are then individually filtered to remove unwanted noise. In this preferred embodiment of the invention, the L-R signal is then filtered to reject a very narrow frequency band centred on the frequency of the unwanted tone, introduced by the PLL. The L-R signal is subsequently added to the L+R signal using summing devices 130 and 140 to produce stereo audio consisting of ‘left’ and ‘right’ signals.
[0027] In an example in which a 32768 Hz reference frequency is used, a 32768 Hz noise signal occurs in the demodulated full composite signal. Once this has been mixed down by 38 kHz, the resulting noise signal is centred around 5232 Hz. In a preferred embodiment of the invention, band rejection filter 110 filters out frequencies around 5232 Hz
[0028] In one embodiment of the invention, filter 110 is a ‘notch’ filter. Such a filter may be implemented as follows:
[0029] Let
[0000]
c
z
=
j
2
π5232
Fs
[0000] and c p =pc z with conventional notation j=√{square root over (−1)}. Then the z-transform of a notch filter centred on 5232 Hz is
[0000]
H
(
z
)
=
(
1
-
c
z
z
-
1
)
(
1
-
c
z
*
z
-
1
)
(
1
-
c
p
z
-
1
)
(
1
-
c
p
*
z
-
1
)
.
(
1
)
[0030] The frequency response of this filter, for p=0.985 and Fs=80 kHz is illustrated in FIG. 9 .
[0031] The L-R signal is subsequently added to the L+R signal which preserves the frequencies around 5232 Hz, producing stereo audio consisting of ‘left’ and ‘right’ signals, having the full range of demodulated frequencies and only lacking some of the stereo information around 5232 Hz. Because the notch filter alters the amplitude and phase of the wanted L-R signal component as well as removing the noise signal at 5232 Hz, the stereo separation is degraded at some frequencies. This is illustrated in FIG. 10 , for the filter described in equation (1) and FIG. 9 . Although the unwanted tone may be rejected by filtering the stereo multiplex signal, this is less effective than the techniques used in the present invention. In this embodiment of the invention, the L+R signal is unaffected and so the distortion to the audio output is minimised. The methodology is also appropriate to reject unwanted sinusoidal components added to the wanted signal as a result of LO imperfections other than reference spurs. The bandwidth and (in a discrete-time representation) the sampling frequency of the L-R signal in a typical receiver are lower than the bandwidth and sampling frequency of the stereo multiplex signal. This normally results in a lower complexity for the filtering operation if it is applied to the L-R signal, compared with an equivalent filtering operation applied to the stereo multiplex signal. As shown in FIG. 10 , the effect of rejecting the noise signal component at 5232 Hz from the L-R signal is that stereo separation is reduced in a narrow band centred on 5232 Hz. This will result in a practically imperceptible loss in quality of the received FM signal.
[0032] FIG. 6 shows another embodiment of the present invention. In this embodiment, the narrow band rejection filter to filter the unwanted noise introduced by the PLL reference spurs may be implemented using a narrow band-pass filter 110 and a subtraction circuit 120 .
[0033] In an embodiment shown in FIG. 7 , the unwanted tone may be removed using a tone estimation and subtraction technique. This may be implemented using a PLL comprising phase comparator 150 , loop filter 160 and oscillator 180 . The L+R signal is passed through a band-pass filter resulting in a signal mostly comprising just the noise tone. The PLL is used to determine the phase of the unwanted tone, while amplitude estimator 170 is used to estimate the amplitude of the unwanted tone. The sinusoid generated by oscillator 180 is amplified by amplifier 190 according to the estimation produced by amplitude estimator 170 . Summing device 120 is used to subtract the amplified sinusoid from the L-R signal, resulting in a L-R signal missing the unwanted tone. Rejection of the unwanted sinusoid using this scheme alters the wanted signal component by less as compared with the preferred scheme using the notch filter. Therefore the stereo separation performance is preserved. However, this implementation has a higher implementation complexity.
[0034] It is conceivable that in some FM receiver implementations, the LO reference frequency is such that the unwanted noise tone resides in a band occupied by a component of the stereo multiplex signal other than the stereo sub-carrier. An example of this scenario is shown in FIG. 8 , where the unwanted tone appears at 70 kHz. In such a case, an embodiment of the present invention provides that the unwanted tone may be rejected by filtering according to the aforementioned techniques. The unwanted tone may be rejected from the signal obtained after the effected sub-carrier is separated from the stereo multiplex.
[0035] Embodiments of the present invention may be used with any device incorporating an FM receiver and where—due to interference or analogue circuit imperfections—an unwanted sinusoid is present in the stereo multiplex signal at a frequency within the band occupied by a desired sub-carrier. Examples may include portable media players, satellite navigation devices and car radios, incorporating an FM receiver.
[0036] The applicant hereby discloses in isolation each individual feature described herein and any combination of two or more such features, to the extent that such features or combinations are capable of being carried out based on the present specification as a whole in the light of the common general knowledge of a person skilled in the art, irrespective of whether such features or combinations of features solve any problems disclosed herein, and without limitation to the scope of the claims. The applicant indicates that aspects of the present invention may consist of any such individual feature or combination of features. In view of the foregoing description it will be evident to a person skilled in the art that various modifications may be made within the scope of the invention. | Apparatus to reduce noise in a stereo FM broadcast received via an antenna, the apparatus comprising: a frequency translator configured to translate the received stereo FM broadcast to an intermediate carrier frequency, a demodulation unit configured to demodulate the translated FM signal so as to form left-plus-right and left-minus-right AM signals, a filter configured to form a filtered signal by filtering one of the AM signals, so as to suppress a sub-band of that signal containing unwanted tones, a summing unit for summing the filtered signal and the other of the left-plus-right and left-minus-right signals to produce a stereo audio signal. | 7 |
FIELD OF THE INVENTION
[0001] This invention is directed to the use of grass lignins in thermoplastics (such as: ultra-high molecular weight polyethylene (UHMWPE)).
BACKGROUND OF THE INVENTION
[0002] Lignin is a by-product of wood pulping or non-wood pulping operations. Lignin's chemical structure is extremely complex. Lignin is generally accepted to be a three dimensional, crosslinked polymer comprised of three different phenyl propenol moieties. The relative amounts of the three monomeric compounds, coumaryl alcohol, coniferyl alcohol, and sinapyl alcohol, vary with the sources of the lignin. Lignins vary in structure according to their method of isolation and their plant sources. Jario H. Lora and W. G. Glasser, “Recent Industrial Application of Lignins: A Sustainable Alternative to Nonrenewable Materials,” Journal of Polymers and Environment, p. 39, (2002). Non-wood sources of lignin include, but are not limited to, bagasse, straw, abaca, sisal, flax, jute, and hemp. Jario H. Lora, “Characteristics, Industrial Sources, Utilization of Lignins from Non-Wood Plants,” Chemical Modifications, Properties, and Usage of Lignin, p. 267, (Plenum Publisher, 2002). Softwood lignins, such as obtained from spruce, pine, redwood, cedar. Hardwood lignins are obtained, or substantially obtained, from oak, cherry, maple, birch, sweet gum, mahogany, and the like.
[0003] A thermoplastic refers to a polymer that softens or melts when exposed to heat and returns to its original condition when cooled. Ultra-high molecular weight polyethylene (UHMWPE) refers to a polymer with molecular weight greater than 1 million and preferably in the range of about 5 million to about 7 million. UHMWPE has many unique properties, but it is extremely difficult to process, i.e., form into usable shapes. Conventional extrusion and molding techniques cannot be used. When extrusion techniques are used, the energy added to the polymer by the extruder may cause chain scissions (e.g., thermal degradation), which, in turn, detrimentally affects the polymer. Rubin, I. I., Editor, Handbook of Plastic Materials and Technology , John Wiley & Sons, Inc., NYC, NY, (1990), p. 349-354, Stein, H. L., “Ultra High Molecular Weight Polyethylene (UHMWPE)”, Engineered Materials Handbook, Vol. 2 Engineering Plastics , ASM International, Metals Park, Ohio, 1988, and U.S. Pat. No. 4,778,601, each is incorporated herein by reference. Accordingly, UHMWPE is often mixed with oils or oils and fillers to facilitate extrusion.
[0004] U.S. Pat. No. 6,485,867, herein incorporated by reference, discloses the use of wood lignins in thermoplastics.
[0005] Poisoning of lead acid storage batteries is known. One poison is antimony (Sb), which is an alloying component of the lead used in the batteries. Antimony poisoning causes a reduction in hydrogen overvoltage. Several solutions to the antimony-poisoning problem have been suggested. For example, see: U.S. Pat. No. 5,221,587—an uncrosslinked natural or synthetic rubber is a layer on or incorporated into microporous or glass fiber separators (also see column 2, line 51—column 3, line 14 for a discussion of additional solutions); U.S. Pat. No. 5,759,716—organic polymers having an affinity for the metal impurity (e.g., Sb) are incorporated into, for example, the separator; European Published Application No. EP 0 910 130 A1-thiolignins are incorporated into fibrous separators; and Japanese Published Application (Kokai) No. 11-191405—lignins are impregnated or coated on a glass mat separator.
[0006] There is still an on-going need to find ways to reduce poisoning in lead acid storage batteries in an economical and efficient manner.
SUMMARY OF THE INVENTION
[0007] The instant invention is directed to the use of grass lignins in thermoplastics (such as: ultra-high molecular weight polyethylene (UHMWPE)). In this invention, grass lignins are added to a lead acid battery separator comprising a microporous membrane including an ultra-high molecular weight polyethylene, a filler, and a processing oil.
DETAILED DESCRIPTION OF THE INVENTION
[0008] In this invention, a grass lignin is added to a microporous battery separator for a lead acid battery made from ultra-high molecular weight polyethylene. The grass lignin acts as an antimony suppressor, which reduces antimony poisoning within the battery. When grass lignins are used, there is a less noticeable discoloration of the separator as in comparison to when wood lignins are used in battery separators. Furthermore, when grass lignins are used, the odor is dramatically reduced as in comparison to when wood lignins are used in battery separators. Battery separators made with ultra-high molecular weight polyethylene are known. See for example U.S. Pat. No. 3,351,495; and Besenhard, J. O., Editor, Handbook of Battery Materials , Wiley-VCH, NYC, NY (1999) p. 258-263, both are incorporated herein by reference.
[0009] The lead acid battery separator generally comprises a microporous membrane made from UHMWPE, fillers, processing oil and lignin. The microporous membrane has an average pore size in the range of about 0.1 to about 1.0 micron, a porosity greater than 10% (preferably between about 55% and about 85%; and most preferably between about 55% and about 70%), and the pore structure is referred to as an open cell structure or interconnected pore structure. The membrane generally comprises about 15-25% by weight UHMWPE, 50-80% by weight filler, 0-25% by weight process oil, and 5-20% grass lignin. Additionally, minor amounts of processing aids may be added. Preferably, the membrane comprises 17-23% by weight UHMWPE, 50-60% filler, 10-20% processing oil, and 5-10% grass lignin. These materials are mixed and extruded in a known fashion. See, for example: U.S. Pat. No. 3,351,495; and Besenhard, J. O., Editor, Handbook of Battery Materials , Wiley-VCH, NYC, NY (1999) p. 258-263, both are incorporated herein by reference.
[0010] UHMWPE refers to polyethylenes with a molecular weight greater than 1 million, preferably greater than 3 million. UHMWPE are commercially available from Ticona LLC, Bayport, Tex.
[0011] Filler refers to high surface area particles with an affinity for the processing oil. Preferred fillers include precipitated silica, oxide compounds, and mixtures thereof. Such silicas are commercially available from PPG, Pittsburgh, Pa. and Degussa-Huls AG, Frankfurt, Germany. Also see U.S. Pat. Nos. 3,351,495 and 4,861,644, incorporated herein by reference, for additional filler suggestions.
[0012] Processing oil (or plasticizer) refers to, for example, mineral oil, olefinic oil; parafinic oil, naphthenic oil, aromatic oil, and mixtures thereof. Processing oil performs two functions; first, it improves the processability of UHMWPE, and second, it is the extractable component, which is used to create the microporous structure of separator. Mineral oil is preferred and is commercially available from Equilon of Houston, Tex. Also see U.S. Pat. Nos. 3,351,495 and 4,861,644, incorporated herein by reference, for additional processing oil (or plasticizer) suggestions.
[0013] Grass lignin refers to those by-products of non-wood pulping operations having extremely complex chemical structures that consist of significant amounts of p-hydroxyphenyl propane derived from coumaryl alcohol precursor. Grass sources of lignin include, but are not limited to, bagasse, straw, abaca, sisal, flax, jute, and hemp. Grass sources from bagasse and flax are preferred. Grass lignins are commercially available from Granit SA, Lausanne, Switzerland.
[0014] Further explanation of this aspect of the invention will be set out in the examples below.
EXAMPLES
[0015] The formulations set out in Table 1 were prepared.
TABLE 1 Sam- Polymer Oil ple (UHMWPE) Filler (Mineral Oil) Lignin Lignin type 1 23% 59% 15% 0% None 2 20% 52% 17.5% 7.5% Grass lignin B 3 20% 52% 17.5% 7.5% Grass lignin F 4 20% 52% 17.5% 7.5% Hardwood Lignin W
[0016] The formulations of Table 1 set out in Table 2 were tested for Sb suppression. Results below were obtained via a cyclic voltammetry technique. Cyclic voltammetry techniques are known., Dietz, H., et al, “Influence of substituted benzaldehydes and their derivatives as inhibitors for hydrogen evolution in lead/acid batteries,” 53 Journal of Power Sources 359-365 (1995), incorporated herein by reference.
TABLE 2 Sb Peak Height Current (mA) at Start Sample (mA) of Sweep @ −1.200 V Sample 1 + 15 ppm Sb 2.81 −2.92 Sample 2 + 15 ppm Sb 0.14 −0.24 Sample 3 + 15 ppm Sb 0.93 −0.24 Sample 4 + 15 ppm Sb 0.62 −0.23
[0017] The formulations set out in Table 3 were prepared.
TABLE 3 Polymer Oil Sample (UHMWPE) Filler (Mineral Oil) Lignin Lignin type 1 20% 52% 17.5% 7.5% Westvaco Hardwood Lignin 2 20% 52% 17.5% 7.5% Grass lignin B 3 20% 52% 17.5% 7.5% Grass lignin F 4 20% 52% 17.5% 7.5% Westvaco Softwood Lignin
[0018] The formulations of Table 3 set out in Table 4 were tested in a 6V golfcart battery for their end of charge current life cycles. Results below were obtained.
TABLE 4 Sample 1 2 3 4 Cycles Current in Amps 2 5.0 5.3 4.6 6.8 24 2.5 2.0 1.7 3.1 49 2.3 2.3 1.6 3.1 74 2.3 2.2 1.8 3.1 99 2.5 2.8 1.9 3.7 124 3.2 3.0 2.1 4.1 149 3.9 3.8 2.4 4.8 174 4.5 3.9 3.3 6.2 199 5.1 4.2 3.0 6.9
[0019] The present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof and, accordingly, reference should be made to the appended claims, rather than the foregoing specification, indicating the scope of the invention. | The instant invention is directed to the use of grass lignin in thermoplastics (such as: ultra-high molecular weight polyethylene (UHMWPE)). In this invention, grass lignins are added to a lead acid battery separator comprising a microporous membrane including an ultra-high molecular weight polyethylene, a filler, and a processing oil. | 2 |
CROSS-REFERENCE TO RELATED APPLICATIONS AND PATENTS
This application is a divisional of the commonly assigned, copending U.S. application Ser. No. 07/359,495, filed: May 31, 1989, entitled "METHOD OF AND APPARATUS FOR TREATING COTTON CONTAMINATED WITH HONEYDEW".
This application is related to the copending U.S. application Ser. No. 07/132,790, filed Dec. 10, 1987, entitled "TREATMENT OF COTTON", now U.S. Pat. No. 4,888,856, granted Dec. 26, 1989, and which application is a divisional application U.S. application Ser. No. 06/833,987, filed Feb. 26, 1986, entitled "TREATMENT OF COTTON", now U.S. Pat. No. 4,796,334 granted Jan. 10, 1989, which is related also to the commonly assigned, copending U.S. application Ser. No. 07/207,252, filed Jun. 15, 1988, entitled "TREATMENT OF COTTON", and which application is a continuation application to the aforementioned parent application, namely U.S. application Ser. No. 06/833,987. This application is also related to the commonly assigned U.S. application Ser. No. 07/359,494, filed May 31, 1989, and entitled "METHOD OF AND APPARATUS FOR REDUCING THE STICKINESS OF COTTON FLOCKS" and to the commonly assigned U.S. application Ser. No. 07/363,784, filed Jun. 9, 1989 and entitled "METHOD OF AND APPARATUS FOR REDUCING THE STICKINESS OF COTTON FLOCKS".
BACKGROUND OF THE INVENTION
The present invention relates to a new and improved apparatus for reducing the stickiness or tackiness of fibers of cotton flocks contaminated with honeydew.
It is known that cotton flocks of many provenances or origins are contaminated or coated to varying degrees with insect secretions which contain sugar. These sugar-containing secretions are generally termed honeydew. There is known a laboratory method by means of which such honeydew is allowed to caramelize by heating cotton flock samples in an oven for the purpose of determining the degree of honeydew contamination from the resulting change in the color of the cotton flocks. This is namely very important because, in the event of considerable contamination, the cotton flocks become sticky or tacky and tend to adhere to various parts of the yarn production plant or to form laps or coils at rolls or rollers or at other rotatable members. This result is very undesirable since it causes frequent interruptions of the yarn manufacturing process.
A method of the aforementioned type is disclosed in European Patent Application No. 86102352.1, published Oct. 8, 1986 under Publication No. 196,449. The object of this known method is to convert any contaminating honeydew into a non-sticky or non-adhesive and brittle state or condition by supplying heat for a short period of time, but without causing any discoloration or change in the color of the cotton flocks, so that the brittle sugar deposits can be crushed and removed in the course of subsequent processing.
A number of devices or apparatus for performing this prior art method have been proposed in the abovementioned European Patent Application No. 86102352.1, published under Publication No. 196,449. One device or apparatus is intended to heat the fiber flocks before the actual opening of the raw cotton bales, i.e. directly at the start of the yarn manufacturing process. Other devices or apparatus are intended for treating fiber slivers before drafting.
SUMMARY OF THE INVENTION
Therefore, with the foregoing in mind, it is a primary object of the present invention to provide a new and improved apparatus for treating cotton flocks contaminated with honeydew, by means of which the honeydew constituent of the contaminated cotton flocks is selectively heated with reduced energy consumption.
Another and more specific object of the present invention aims at providing a new and improved apparatus for treating cotton flocks, in which a uniform cotton flock batt or web is achievable and detrimental or undesired effects of uncontrolled heating are obviated.
To achieve the aforementioned objects, the inventive apparatus, in its more specific aspects, is manifested, among other things, by the features that the apparatus comprises a housing with a roof structured as an extraction or exhaust hood, a tunnel-type or tunnel-shaped microwave oven arranged in the housing and provided with an inlet and an outlet, a conveyor belt or band made of a material absorbing little microwave energy and provided for conveying the cotton flocks through the tunnel-type or tunnel-shaped microwave oven, and two deflection rolls or rollers each arranged at the inlet and the outlet of the tunnel-type or tunnel-shaped microwave oven, the conveyor belt being guided around these two deflection rolls or rollers, one of which is driveable.
The apparatus constructed according to the invention is based on the recognition that the water molecules contained in sugardew or honeydew are preferentially set into oscillation or vibration by microwave irradiation, thus effecting a more intensive heating of the honeydew constituent in comparison with the other constituents of the cotton flock web, so that the honeydew constituents are converted into the desired or required non-sticky or non-adhesive state. Such selective heating of the honeydew constituent substantially reduces the amount of heat energy required for the process as compared with other heating processes and obviates an excessive temperature of the cotton flocks themselves, so that the fire hazard or risk which must always be taken into account in the treatment of cotton flocks is substantially reduced. In this manner, the risk of an undesired or unwanted discoloration of the cotton flocks is precluded to a very large extent.
The energy supply to the cotton flocks may be effected during an intermittent or batch processing operation, i.e. the conveyor belt or band may stop in the microwave oven while the cotton flocks deposited thereupon are heated. However, the apparatus of the invention preferably carries out in a continuous or non-intermittent processing operation, i.e. heating is effected during the travel or movement of the conveyor belt or band through the tunnel of the microwave oven. One advantage of this is that the apparatus of the invention can be appropriately integrated into the yarn manufacturing process in which a continuous feed or supply of fiber flocks to the card or carding machine is desirable. Furthermore, the cotton flock web experiences, by virtue of the continuous movement, a uniform energy density and a correspondingly dosed amount of energy in the tunnel of the microwave oven, so that a particularly uniform heating of the honeydew constituents is accomplished. Therefore, there is avoided local heating of the cotton flock web to temperatures which would represent a fire hazard. In addition, there is no need for any form of wave agitator or stirrer since the energy density in the cotton flock web is rendered uniform by the continuous travel or movement.
Vapors escaping during the supply of heat in the microwave oven are preferably extracted during the heating process, so that the cotton flock web is already dry upon leaving the microwave oven.
A particularly preferred variant of the invention is characterized in that the fiber flocks remain in the tunnel-type or tunnel-shaped microwave oven for a time period in the range of 5 to 45 seconds, preferably from 20 to 40 seconds, and particularly during approximately 30 seconds, and that the energy supply is in the range of 50 to 300 kJ per kilogram of cotton, preferably at about 170 kJ per kilogram of cotton, for a flock web having a width in the range of 80 to 120 cm and a thickness in the range of 5 to 15 cm. The values indicated can be obtained with conventional apparatus or installations for processing cotton and with commercially available microwave generators as produced, for example, by the company Gigatherm in Heiden, Appenzell A.Rh., Switzerland.
More particularly, to achieve the maximum required energy density for a throughput of, for example, 300 kilograms cotton per hour, there are required about 5 to 15 microwave generators, preferably 12 microwave generators, each having an output power of 1.2 kilowatt, such microwave generators being preferably arranged in two rows.
A control of the energy density is effected not only by controlling the output energy of each microwave generator, but also can be varied within very broad limits by switching off one or several microwave generators. Furthermore, it is also possible to equip the installation with more microwave generators than would be necessary for the maximum degree of contamination, so that in the event of failure of one or the other microwave generator a new microwave generator can be placed into use. In this manner, the service life of the microwave oven can be substantially extended.
In the case of cotton flocks having only a low degree of honeydew contamination, the entire tunnel-type or tunnel-shaped microwave oven can be by-passed or put out of operation without this having any disadvantageous effects on the processing of the cotton flocks. It is, for instance, unnecessary to make any changes to the layout or design of the complete fiber processing installation or plant.
If, as indicated hereinbefore, the tunnel-type microwave oven consists of several microwave generators which can be operated at the same time or individually, then these preferably ten to fourteen microwave generators, in particular or advantageously twelve microwave generators, are preferably arranged in two rows and preferably above the conveyor belt or band. In this manner, using microwave generators having a commercially available width of about 40 cm, it is possible to arrange such microwave generators side by side in two rows with a lateral spacing, such that a flock web having a width of about 100 cm can be uniformly irradiated with microwaves i.e. microwave energy. The aforesaid width of 100 cm corresponds to the conventional width of the flock web at the outlet or exit of a blending opener or flock feeder, so that the microwave oven constructed according to the invention can be readily integrated into an existing installation or plant. The microwave oven constructed according to the invention or the inventive method or the inventive apparatus also can be applied or used in ginning.
For the protection of the operating personnel, preferably ferrite bar or rod arrangements or arrays are provided at the inlet and the outlet of the tunnel formed by the microwave oven. The openings at the inlet and the outlet of the microwave oven, the housing of which otherwise consists of full-length or solid sheet metal, are protected by these ferrite bars or rods from any possible escape of microwave radiation.
For the same purpose, there are provided screening plates which are arranged at the inlet and outlet sides upstream and downstream of the tunnel formed by the microwave generators and which extend preferably transversely with respect to the direction of travel of the cotton flock web and terminate directly in front of the surface of the cotton flock web.
When integrating the microwave oven constructed according to the invention in a cotton flock processing plant or unit, the cotton flock feed to the conveyor belt is effected through a flock chute or shaft which is arranged at the inlet or entry end of the microwave oven and has take-up or delivery rolls or rollers disposed at the bottom or lower end or end region of the flock chute or shaft. The cotton flock web delivered at the outlet or exit end of the tunnel-type microwave oven is preferably fed to an opening unit of a cleaning machine which feeds a flock feeder arranged upstream of one or several cards or carding machines.
As a variant, the cotton flock web can be cooled in a cooling zone, operated with cooling air, before the cotton flock web is fed to the opening unit of a cleaning machine. In this manner, the stickiness or tackiness of honeydew is still further reduced.
Finally, it should be mentioned that a particularly preferred embodiment of the apparatus constructed according to the invention is characterized in that alarm-type sensors or detectors are arranged within the housing of the tunnel-type microwave oven and are coupled by means of a control system with a halon gas fire-extinguishing installation. If a fire occurs in the microwave oven due to any unforeseen circumstances, the fire-extinguishing installation can extinguish this fire and simultaneously switch off the microwave generators. In this manner, effective fire control within the quasi-closed microwave oven is rendered possible.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be better understood and objects other than those set forth above will become apparent when consideration is given to the following detailed description thereof. Such description makes reference to the annexed drawings wherein throughout the various figures of the drawings, there have been generally used the same reference characters to denote the same or analogous components and wherein:
FIG. 1 shows a schematic side view of a part of a plant processing cotton flocks;
FIG. 2 is a schematic sectional view taken substantially along the lines 2--2 in FIG. 1; and
FIG. 3 schematically shows a variant of the plant illustrated in FIG. 1.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Describing now the drawings, it is to be understood that to simplify the showing thereof, only enough of the structure of the apparatus for realizing the inventive method of treating cotton flocks contaminated with honeydew has been illustrated therein as is needed to enable one skilled in the art to readily understand the underlying principles and concepts of this invention. Turning attention now specifically to FIG. 1 of the drawings, the apparatus illustrated therein by way of example and not limitation will be seen to comprise an outlet chute or shaft 13 of a combined blending and cleaning machine 10, for example, the Rieter Unimix B 7/3 or the Rieter blending opener B 3/3 of the assignee of this application, which is arranged upstream of a microwave oven 11 constructed according to the invention, which is followed by an opening unit 12. This opening unit 12 could be the opening unit of a fine cleaning machine such as, for example, the Rieter ERM cleaning machine.
The fiber flocks present in the outlet chute or shaft 13 of the combined blending and cleaning machine 10, which fiber flocks may be a blend of cotton flocks of different origins or provenances, are formed into a slightly compressed cotton flock web 17 by a guide roll or roller 14 and two take-up or delivery rolls or rollers 15 and 16. This slightly compressed cotton flock web 17 is continuously deposited on a revolving conveyor belt or band 18. The revolving conveyor belt or band 18 is composed of a suitable material, for instance of silicon or polypropylene, which is practically non-absorbent or totally non-absorbent with respect to microwaves. This revolving conveyor belt or band 18 is guided or trained around two deflection rolls or rollers 19 and 21, of which the deflection roll or roller 21 is driven by a suitable drive motor not particularly shown in the drawing. Further deflection rolls or rollers and tension rolls or rollers can also be provided but are not particularly shown in the drawings.
As depicted in FIG. 1, the first deflection roll or roller 19 is already arranged just downstream of the pair of take-up or delivery rolls or rollers 15 and 16 of the combined blending and cleaning machine 10 and is separated from this pair of take-up or delivery rolls or rollers 15 and 16 by means of a guide plate 22 provided for the slightly compressed cotton flock web 17. The driven deflection roll or roller 21 is located directly downstream of the outlet or exit of the microwave oven 11 and upstream of infeed or intake rolls or rollers 23 and 24 of the opening unit 12 which, in the further course or path of the cotton flock web 17, consists of feed rolls or rollers 25 and 26, a cleaning roll or roller 27 and a grating or grid 28. The cotton flock web 17 received from the revolving conveyor belt or band 18 is opened and cleaned by the cleaning roll or roller 27 and the opened or loosened cotton flocks are subsequently fed into a vertically ascending shaft or chute 29 leading to a suitable flock feeder not particularly shown in the drawing.
As can be seen also in FIG. 2, the microwave oven 11 consists of two rows 30.1 and 30.2 each containing, for instance, six microwave generators 31. The slightly compressed cotton flock web 17, which is deposited on the conveyor belt or band 18 and has, for instance, a width of 1 meter and a thickness of about 10 cm, lies approximately 15 cm below the bottom or lower ends of the microwave generators 31, so that the microwaves or microwave energy emitted from these microwave generators 31 have the possibility of being uniformly distributed across the width of the slightly compressed cotton flock web 17. This uniform distribution of the microwaves is beneficially influenced by the multiple or repeated reflections at metallic walls 32 of a microwave-oven housing 33 or at a metallic support plate 35 provided beneath the top run or strand 34 of the revolving conveyor belt or band 18.
To prevent radiation deflected by multiple or repeated reflections from escaping through the inlet or the outlet of the microwave oven 11, there are provided screening plates 36 which are mounted at the inlet and outlet sides and which extend from the bottom or lower side of the microwave generators 31 down to just above the surface of the slightly compressed cotton flock web 17. Furthermore, there are present substantially parallel arrangements or arrays of ferrite bars or rods 39 and 41 arranged around a substantially rectangular inlet 37 and a substantially rectangular outlet 38 of the microwave oven 11. Such arrangements or arrays of ferrite bars or rods 39 and 41 absorb any possibly still present microwaves and thus prevent that these microwaves enter the housing of the combined blending and cleaning machine 10 or in this manner reach the opening unit 12. Such radiation is thus kept away from the operational staff.
Above the microwave generators 31 the roof or upper side of the microwave-oven housing 33 is structured as an exhaust or extraction hood 42 and a suitable blower or ventilator not particularly shown in the drawings sucks out or extracts the vapors generated by the microwave heating through a connecting pipe or spigot or stud 43 provided at the top end of the exhaust or extraction hood 42.
Within the microwave-oven housing 33 there are provided various infrared alarm-type sensors or detectors 44, which are connected to a suitable control system 80 equipped with an alarm or signal device 81. In the event of local overheating during operation, the plant and above all the microwave generators 31 are switched off by the control system 80 and a halon extinguishing gas is delivered through nozzles or jets 45 into the microwave-oven housing 33. Oxygen is thus driven out and a fire outbreak is prevented or a developing fire is immediately extinguished.
A power control of the individual microwave generators 31 is possible within certain limits, but the overall power of the plant or installation can be achieved within wide limits by switching on or off individual microwave generators 31.
In this manner, it is possible to readily adapt the heat input or supply to the moisture or humidity content of the cotton and the honeydew contamination.
The microwave devices themselves operate with a wave length of 12 cm at a frequency of 2.45 gigahertz.
The energy supply to the slightly compressed cotton flock web 17 should be dimensioned such that, subject to the speed of passage or travel of the revolving conveyor belt or band 18, the honeydew deposits are heated to about 140° C. This is sufficient to withdraw or extract about 80% of the water contained in such honeydew deposits and convert the latter into a readily processable non-adhesive or no longer tacky condition or state.
Finally, it should be mentioned that it is possible to provide, within the microwave-oven housing 33, controllable deflectors 46 for controlling or directing the microwaves. Such controllable deflectors 46 shown in FIG. 2 are arranged between the adjacent rows 30.1 and 30.2 of the microwave generators 31. These controllable deflectors 46 can be controlled such that a uniform energy distribution across the entire width of the slightly compressed cotton flock web 17 is obtained, without the radiation produced by the two adjacent microwave generators 31 in the middle of the cotton flock web 17 resulting at that location in local overheating of the cotton flock web 17 or of the honeydew deposits. Normally during fabrication of the microwave oven 11, such controllable deflectors 46 are finally adjusted with due regard to the properties of the microwave generators 31 installed in the microwave oven 11.
FIG. 3 shows a variant of the plant illustrated in FIG. 1 inasmuch as a cooling zone 70 is provided between the deflection roll or roller 21 of the revolving conveyor belt or band 18 and the infeed or intake rolls or rollers 23 and 24. This cooling zone 70 is provided for cooling the heated cotton flock web 17 between two cooling conveyor belts or bands 71 and 72. The cooling zone 70 is covered by an exhaust or extraction hood 73 at which a connecting pipe or spigot or stud 74 is provided. This connecting pipe or spigot 74 is connected to a suitable suction fan (not shown) for generating, for instance, a substantially vertical air current or forced flow L through the cooling conveyor belts or bands 71 and 72.
In the walls which surround or enclose the cooling zone 70 and the opening unit 12 to which the infeed or intake rolls or rollers 23 and 24 belong, there are provided air inlet openings (not shown) to let in the aforesaid air current or forced flow L and the air for the vertically ascending shaft or chute 29.
Depending on the desired or required air moisture or humidity content and the desired or required air temperature of the air current or forced flow L, there can be provided an air conditioning device (now shown) to precede the aforementioned air inlet openings.
The two cooling conveyor belts or bands 71 and 72 are synchronously driven by a suitable single drive which is not particularly shown in the drawing. These cooling conveyor belts or bands 71 and 72 convey the cotton flock web 17 at the outgoing or output speed of the cotton flock web 17 on the revolving conveyor belt or band 18.
As a further variant not particularly shown in the drawings, there is also the possibility of cooling the cotton flock web 17 after or downstream of the opening unit 12. For this purpose, the vertically ascending shaft or chute 29 should have a cross-section and a length which render possible the cooling of the web during its conveyance. In such a case, the velocity of air in the vertically ascending shaft or chute 29 will be slightly above the suspension speed of the cotton flocks, in order to render possible a sufficient or adequate dwell time without an all too excessive height of the vertically ascending shaft or chute 29. There also exists the possibility of air conditioning the air before being drawn into the vertically ascending shaft or chute 29.
While there are shown and described present preferred embodiments of the invention, it is to be distinctly understood that the invention is not limited thereto, but may be otherwise variously embodied and practiced within the scope of the following claims. | The invention relates to an apparatus for treating cotton contaminated or imbued with honeydew. For this purpose, cotton flocks are fed into a microwave oven, in which the cotton flocks are heated by microwave energy, thus reducing the stickiness or tackiness of the honeydew such that there are no processing disadvantages on subsequent machinery. The microwave oven basically comprises a conveyor belt on which the cotton flocks are conveyed through a passage or channel provided with microwave generators. At the exit or outlet of the microwave oven the cotton flocks are transferred to an opening unit which transfers the cotton flocks into a feed chute or shaft. | 3 |
[0001] This application claims the benefit of Indian provisional Application 3983/DEL/2012, filed Dec. 21, 2012 which is herein incorporated by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to improvement of the thermal stability of a polyethylene planar substrate using suitable coatings.
[0004] 2. Description of the Related Art
[0005] The use of nonwoven fabrics as a printing medium has been proposed in various prior patent documents, such as for example, U.S. Pat. No. 5,240,767, U.S. Pat. No. 5,853,861 and U.S. Pat. No. 6,210,778. However, little attention is given to the structural and physical properties of the nonwoven fabric required to make the fabric a commercially acceptable substrate for digital printing applications. One of the problems inherent with the manufacture of nonwoven fabrics by conventional manufacturing methods is that the fiber deposition can be uneven or variable, producing thick and thin spots or other variations in basis weight that render the material unappealing or unsuitable for use as a printing medium. As a result, very few nonwoven fabrics have found commercial acceptance as a printing medium.
[0006] US Patent Publication 2004/0248492 A1 discloses a nonwoven printing medium made by laminating two or more nonwoven layers together to provide sufficiently uniform thickness and basis weight and sufficient structural properties to be suitable for use in various commercial printing operations such as, for example, ink-jet printing and laser printing, as well as the more traditional printing technologies of flexography, lithography, letterpress printing, gravure and offset.
[0007] U.S. Pat. No. 6,210,778B1 discloses a laser printable non-woven polyester fabric coated with a polyurethane or polyurethane-polyester blend coatings. The coating weight disclosed in '778 is high (2.5 oz/yd) and adds significant basis weight to the fabric.
[0008] There is a need for a laser printable substrate that shows little or no shrinkage when printed.
SUMMARY OF THE INVENTION
[0009] An aspect of this invention is a layer of polyethylene and a layer of a coating, the layer of coating comprising a cross-linked polymer covering at least a portion of the surface of the layer of polyethylene, wherein the coating has a weight of 80 gsm or less.
[0010] In one embodiment of the invention, the substrate shows less than 15% dimensional change in either the longitudinal or transverse directions when subjected to a thermal stability test in which the substrate is printed upon in a laser printer.
[0011] In another embodiment of the invention, the substrate shows no dimensional change in longitudinal or transverse direction when subjected to a thermal stability test in which the substrate is printed upon in a laser
[0012] In another embodiment of the present invention, the substrate shows no dimensional change in longitudinal or transverse direction when subjected to a thermal stability test in which the substrate is printed upon in a laser In an embodiment of the present invention, the cross-linked coating is selected from the group consisting of vinyl ester, unsaturated polyesters, alkyds, epoxies, phenolic resin, polyisocyanate, polyurea, polyacrylates, polyamides, perfluoro acrylates, cyanoacrylates, polyurethane polyethylene, cellulose, and combinations.
[0013] In another embodiment of the present invention, the polyethylene planar substrate is in a form selected from the group consisting of film, woven, non-woven and any combination thereof.
[0014] In a further embodiment the polyethylene planar substrate comprises a plexifilamentary web.
[0015] In still another embodiment of the invention, the coating further comprises fillers that are selected from the group consisting of sodium acetate, potassium acetate, sodium iodide, calcium sulfate, silica, calcium carbonate, titanium dioxide, silver nanoparticles, photoluminiscent materials, UV reactive pigments, carbon black and any combination thereof.
[0016] In another embodiment, the polyethylene is metallized on at least one side prior to coating.
[0017] Another aspect of this invention is a process for preparing a planar substrate, comprising the steps of:
I. providing a planar polyethylene substrate, II. applying a coating solution to the polyethylene substrate, III. curing the coated polyethylene at a temperature between 20 and 130° C., and IV. annealing the coated polyethylene at a temperature between 75 and 130° C.
[0022] wherein the coating solution is applied in a solution to the layer of polyethylene.
[0023] In one embodiment of the present invention, in the process for preparing a planar substrate, the coating is applied by a process selected from dip coating, knife coating, brush coating, gravure coating, Meyer rod coating, spray coating and combinations thereof.
DETAILED DESCRIPTION OF THE INVENTION
[0024] Applicant specifically incorporates the entire contents of all cited references in this disclosure. Further, when an amount, concentration, or other value or parameter is given as either a range, preferred range, or a list of upper preferable values and lower preferable values, this is to be understood as specifically disclosing all ranges formed from any pair of any upper range limit or preferred value and any lower range limit or preferred value, regardless of whether ranges are separately disclosed. Where a range of numerical values is recited herein, unless otherwise stated, the range is intended to include the endpoints thereof and all integers and fractions within the range. It is not intended that the scope of the invention be limited to the specific values recited when defining a range.
[0025] The present invention is directed to a planar substrate comprising a layer of polyethylene and a layer of a coating, the layer of coating comprising a cross-linked polymer covering at least a portion of the surface of the layer of polyethylene, wherein the coating has a weight of 80 gsm or less.
[0026] For purposes of describing the features of the coated polyethylene described herein, the term “coating’ is defined as a material layer in adherence with either surface (one or both sides) or bulk morphology of a porous substrate.
[0027] The term “planar substrate” as used herein refers to a substrate which has first and second opposite sides and lies generally in a plane. For purposes of this disclosure, a first side of the substrate is said to be “opposite” a second side of the substrate if said first and second sides lie in generally parallel planes and are separated by an edge, which is the thickness of the substrate.
[0028] “Cross-linkable” refers to polymer chains bonded to other chains at multiple points producing a highly interlinked structure.
[0029] “Dimensional change” refers to change in longitudinal or transverse direction dimensions when exposed to elevated temperatures.
[0030] “Porous” refers to a material that has a significant amount of voids, capillaries, communicated holes, and/or fissures.
[0031] “Laminate” refers to a material layer in adherence with only surface morphology of a primary porous substrate and can be considered as a synonym of “coating”.
[0032] ‘Thermal stability test” refers to test method used to determine the dimensional changes of the coated polyethylene substrate based on the application. The thermal stability tests are described in detail in the test method section.
[0033] The term “nonwoven” means here a web including a multitude of randomly oriented fibers. By “randomly oriented” is meant that the fibers have no long range repeating structure discernable to the naked eye. The fibers can be bonded to each other, or can be unbonded and entangled to impart strength and integrity to the web. The fibers can be staple fibers or continuous fibers, and can comprise a single material or a multitude of materials, either as a combination of different fibers or as a combination of similar fibers each comprised of different materials.
[0034] Nonwoven fabrics or webs have been formed from many processes such as for example, meltblowing processes, spunbonding processes, and bonded carded web processes. The basis weight of nonwoven fabrics is usually expressed in ounces of material per square yard (osy) or grams per square meter (gsm) and the fiber diameters useful are usually expressed in micrometers. (Note that to convert from osy to gsm, multiply osy by 33.91).
[0035] As used herein the term “microfibers” means small diameter fibers having an average diameter not greater than about 75 micrometers, for example, having an average diameter of from about 0.5 micrometers to about 50 micrometers, or more particularly, microfibers may have an average diameter of from about 2 micrometers to about 40 micrometers. The diameter of, for example, a polypropylene fiber given in micrometers, may be converted to denier by squaring, and multiplying the result by 0.00629, thus, a 15 micrometer polypropylene fiber has a denier of about 1.42 (15 2 ×0.00629=1.415).
[0036] As used herein the term “spunbond fibers” refers to small diameter fibers which are formed by extruding molten thermoplastic material as filaments from a plurality of fine, usually circular capillaries of a spinnerette with the diameter of the extruded filaments then being rapidly reduced as by, for example, U.S. Pat. No. 4,340,563 to Appel et al., U.S. Pat. No. 3,692,618 to Dorschner et al U.S. Pat. No. 3,802,817 to Matsuki et al., U.S. Pat. No. 3,338,992 U.S. Pat. No. 3,341,394 to Kinney, U.S. Pat. No. 3,502,763 and U.S. Pat. No. 3,542,615 to Dobo et al. Spunbond fibers are generally continuous and larger than 7 micrometers, more particularly, they are usually between about 15 and 50 micrometers.
[0037] The substrate of the invention may comprise a plexifilamentary web. The term “plexifilamentary” refers to a planar structure which is characterized by a morphology substantially consisting of a three-dimensional integral network of thin, ribbon-like, film-fibril elements of random length that have a mean film thickness of less than about 4 micrometers and a median fibril width of less than 25 micrometers, and that are generally coextensively aligned with the longitudinal axis of the yarn. In plexifilamentary yarns, the film-fibril elements intermittently unite and separate at irregular intervals in various places throughout the length, width and thickness of the yarn, thereby forming the three-dimensional network.
[0038] U.S. Pat. No. 3,081,519 to Blades et al. describes a process wherein a solution of fiber-forming polymer in a liquid spin agent that is not a solvent for the polymer below the liquid's normal boiling point, at a temperature above the normal boiling point of the liquid, and at autogenous pressure or greater, is spun into a zone of lower temperature and substantially lower pressure to generate plexifilamentary film-fibril strands. As disclosed in U.S. Pat. No. 3,227,794 to Anderson et al., plexifilamentary film-fibril strands can be obtained using the process disclosed in Blades et al. when the pressure of the polymer and spin agent solution is reduced slightly in a letdown chamber just prior to flash-spinning.
[0039] In a laser printing machine, the toner particles atop a printable substrate such as paper are melted and impregnated into the porous substrate through simultaneous application of high temperature (150-220° C.) and pressure (100-150 pounds per square inch or 690 to 1034 kPa.) This step is accomplished at the fuser section of a laser printer and lasts approximately between 0.5 and 5 seconds, depending on the speed of printing and printing engine design.
[0040] For a polyolefin non-woven substrate to be used in this application, it is imperative that the substrate withstand the fuser conditions. Else, the substrate can melt, shrink, or curl and jam the printing process. Since the melting point (T m ) of polyethylene is about 135° C. (when tested in a differential scanning calorimeter at a scan rate of 10° C./min), it tends to shrink or melt as the fuser conditions are applied and a laser printable sheet cannot be obtained.
[0041] The current invention is intended to improve the thermal stability characteristics of a lower melting point porous substrate (such as a plexifilamentary or spunbond web), so as to withstand temporary application of temperatures over its melting point even at a pressure above atmospheric.
[0042] An aspect of this invention is a planar substrate comprising a layer of polyethylene and a layer of a coating comprising a cross-linked polymer covering at least a portion of the surface of the layer of polyethylene, wherein the coating has a weight of 80 gsm or less.
[0043] In one embodiment of the invention, the substrate shows less than 15% dimensional change in either the longitudinal or transverse directions when subjected to a thermal stability test in which the substrate is printed upon in a laser printer.
[0044] In another embodiment of the invention, the substrate shows no dimensional change in longitudinal or transverse direction when subjected to a thermal stability test in which the substrate is printed upon in a laser.
[0045] In an embodiment of the present invention, the cross-linked coating is selected from the group consisting of vinyl ester, unsaturated polyesters, alkyds, epoxies, phenolic resin, polyisocyanate, polyurea, polyacrylates, polyamides, perfluoro acrylates, cyanoacrylates, polyurethane polyethylene, cellulose, and combinations.
[0046] In another embodiment of the present invention, the polyethylene planar substrate is in a form selected from the group consisting of film, woven, non-woven and any combination thereof.
[0047] In another embodiment of the present invention, the polyethylene planar substrate comprises a plexifilamentary web.
[0048] In still another embodiment of the invention, the coating further comprises fillers that are selected from the group consisting of sodium acetate, potassium acetate, sodium iodide, calcium sulfate, silica, calcium carbonate, titanium dioxide, silver nanoparticles, photoluminiscent materials, UV reactive pigments, carbon black and any combination thereof.
[0049] In another embodiment, the layer of polyethylene is metallized on at least one side prior to coating.
[0050] Another aspect of this invention is a process for preparing a planar substrate comprising the steps of:
providing a planar polyethylene substrate, applying a coating solution to the polyethylene substrate, curing the coated polyethylene at a temperature between 20 and 130° C., and annealing the coated polyethylene at a temperature between 75 and 130° C. wherein the coating solution is applied in a solution to the layer of polyethylene.
[0054] In one embodiment of the present invention, in the process for preparing a planar substrate, the coating is applied by a process selected from the group consisting of dip coating, knife coating, brush coating, gravure coating, meyer rod coating, spray coating and combinations thereof.
EXAMPLES
Test Methods
[0055] An A4 size (210 mm×297 mm) coated sample is loaded into the feeder tray of a Canon® LBP2900 B&W laser printer or a Ricoh Aficio 4501 color laser printer. The maximum fuser temperature is about 180° C. as measured using an Infrared camera, with emissivity set at 0.9, pointed at the exposed fuser component. Print command is then given to print 5 lines of text and the A4 sheet travels through toner deposition step and fusing step to give a printed sheet. The coated sample is considered to be thermally stable when less than 10% dimensional change is observed.
Materials
[0056] Flash spun non-woven high density polyethylene webs (Tyvek® 1073D, a 75 g/m 2 basis weight, and Tyvek® 1082D, 105 g/m 2 basis weight.) were obtained from E.I. DuPont de Nemours Company, Wilmington, Del. (DuPont)
[0057] Polyimide film was obtained from DuPont under the tradename Kapton®.
[0058] A water based commercial grade of acrylic emulsion (Premium Acrylic emulsion) was obtained from Asian Paints, India.
[0059] A cross-linkable hydrophilic aliphatic polyisocyanate based on hexamethylene diisocyanate (HDI) (Bayhydur XP 2655) was obtained from Bayer® Material Science.
[0060] Hydroxyfunctional polyacrylate dispersion (Bayhydrol A 2601) which was used in combination with aliphatic polyisocynates for formulation of waterborne two-component coatings, was obtained from Bayer® Material Science.
[0061] A 40 wt % dispersion of colloidal silica (22 nm in diameter) in water (Ludox® 40) was obtained from Sigma-Aldrich.
[0062] An aliphatic polyisocyanate based on hexamethylene diisocyanate (HDI) and supplied as 90% in butyl acetate/solvent naphtha 100 (1:1) (Desmodur N 3390 BA/SN), was obtained from Bayer® Material Science.
Comparative Example A
[0063] A polyethylene plexifilamentary web sample (Tyvek® 1073D) was tested for dimensional changes by placing a 2.5″×1.5″ (6.4 cm×3.8 cm) sample on a hot plate. The hot plate was first heated to a temperatures of 140, 150, 160, 170, 180, 190° C. and allowed for 15 min to equilibrate along with two Kapton® polyimide sheets left on the hot plate. After 15 minutes, the web sample was placed between the polyimide sheets on the hot plate with a 1 kg load on the sample for 3 seconds. The Tyvek® sample held at different set temperatures ranging from 140 to 190° C. lost dimensional stability and gradually turned transparent.
Comparative Example B
[0064] 15 gm of an acrylic emulsion (Asian Paints, India) was well mixed in 50 cc of DI water and coated on both sides of a plexifilamentary web (Tyvek® 1073D) using a paint brush. The coated sheet was then cured in an oven at 100° C. for 60 minutes to obtain a dry coat weight of 25 g/m 2 . Solvent (Acetone) wash of the dried sample showed that the emulsion coating dissolved completely indicating that no crosslinking had taken place.
[0065] Next, the coated sheet was passed through a Ricoh Aficio 4501 color laser printer. However, the substrate lodged at printer's fuser section and the recovered sample showed complete disintegration of non-woven due to high temperature and pressure applied during the printing process.
Example 1
[0066] 15 gm of Desmodur® N 3390 was well mixed with 50 cc of Acetone to form a consistent solution. The coating was then applied on a plexifilamentary web (Tyvek® 1073D) using a 16 micrometer Meyer rod and then cured in the oven at 100° C. for 60 minutes. A dry coat weight of about 35 g/m2 was obtained. A solvent wash of the coated sample did not show any dissolution of coating, indicating a formation of highly crosslinked network. Next, the coated sheet was passed through a Ricoh Aficio 4501 color laser printer. The printed sample showed 0% dimensional change.
Example 2
[0067] 15 gm of Desmodur® N 3390 was mixed with 10 cc of Acetone to form a consistent solution. The coating was then applied on a plexifilamentary web (Tyvek® 1073D) using a 16 micrometer Meyer rod and then cured in the oven at 100° C. for 120 minutes. A dry coat weight of about 76 g/m 2 was obtained. A solvent wash of the coated sample did not show any dissolution of coating, indicating a formation of highly crosslinked network. Next, the coated sheet was passed through a Ricoh Aficio 4501 color laser printer. The printed sample showed 0% dimensional change.
Example 3
[0068] 10 grams of Bayhydrol XP 2601 (Bayer® Material Science) was mixed well with 50 ml of DI water, followed by 5 grams of Bayhydur XP 2655 and 1 gram of Sodium Acetate. 10 cc of Ludox® 40 aqueous dispersion of colloidal silica were then added to the solution. The composition was then coated on Tyvek® 1082D, on a single side in one instance, and on both sides for another sample. After curing the coated sheets using a hot air gun at 120° C. set point, the samples were printed using a Canon® LBP2900 laser printer. A 0% dimensional change was observed in the printed samples and the sheets also displayed excellent text resolution without any smudging.
Example 4
[0069] A Premium acrylic based paint emulsion (Premier Emulsion®, Asian Paints, India) with nearly 50 wt. % inorganic filler (1:1 wt ratio TiO 2 and CaCO 3 ) was coated (base coat) on one side of a plexifilamentary web (Tyvek® 1082D) using a paint brush (base coat).
[0070] 6 gm of Bayhydur XP 2655 was mixed well with 50 cc of DI water, followed by 9 gm of Bayhydrol XP 2601, 10 gm of 50 wt % TiO 2 in water dispersion, and 1 gm of anhydrous Sodium acetate. This dispersion was coated using a paint brush on the same side of plexifilamentary web (Tyvek® 1082D) (top coat) and cured at 100° C. using a hot air gun. The coated sheet was then annealed at a temperature of 120° C. Coat weights of the base and top coats were 15 g/m 2 and 8 g/m 2 , respectively. The single side coated sheet was printed on a Canon® LBP2900 laser printer. A 0% dimensional change was observed and the printed sheet also showed excellent resolution without any smudging. Upon printing, it was observed that the single side coated sample did not display any curling effect. | A flash spun non-woven polyethylene is coated with suitable thermally stable coating to make the non-woven polyethylene suitable for high temperature applications including digital printing and also a method for preparation of such thermally stable non-woven polyethylene. | 3 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a reforming reactor, and more particularly to the structure of the reforming reaction section of the reforming reactor.
2. Description of Related Art
FIG. 10 is a sectional view showing an example of a conventional plate-shaped reforming reactor described, for example, in "ISHIKAWAJIMA-HARIMA TECHNICAL PUBLICATION (Vol. 31, No. 6, November, 1991)." This reforming reactor 1 includes a reforming chamber 2 for advancing a reforming reaction and a heating chamber 4 provided adjacent to the reforming chamber 2. The reforming chamber 2 forms a reaction gas flow passage through which reaction gas passes, and a reforming catalyst 3 is held in the interior of the reforming chamber 2. The reforming chamber 2 and the heating chamber 4 are partitioned by a partition wall 5. In the interior of the heating chamber 4 there is held a catalytic combustion catalyst 6.
The reforming reactor 1 is constructed such that it supplies fuel gas and air to the heating chamber 4, in turn this fuel gas burns by the chemical reaction with the aid of the catalytic combustion catalyst 6, and heats the reforming chamber 2.
In FIG. 10, an arrow 7 indicates the flow of the reaction gas which is supplied to the reforming chamber 2 and which is mainly composed of hydrocarbon or an alcohol and steam that are exhausted. An arrow 8 indicates the flow of the fuel gas for heating which is supplied to the heating chamber 4, an arrow 9 indicates the flow of air which is supplied to the heating chamber 4, and an arrow 10 indicates the flow of exhaust gas which is exhausted from the heating chamber 4.
Now, the operation will be described. If reaction gas 7 containing raw material, such as hydrocarbon or an alcohol, and steam is externally supplied to the reforming chamber 2 of the reforming reactor 1, then hydrocarbon or alcohol will react in the reforming chamber 2 with steam by a reforming reaction with the aid of the reforming catalyst 3 and be converted into hydrogen, carbon monoxide and carbon dioxide gas. In the case of hydrocarbon being methane, this reaction is expressed by Equation (1).
CH.sub.4 +H.sub.2 O->CO+3H.sub.2 . . . ( 1)
When this occurs, the reforming reaction which occurs on the reforming catalyst 3 is an endothermic reaction. The reaction heat needed to keep up the endothermic reaction is supplied from the heating chamber 4 side of the reforming reactor 1 through the partition wall 5. To the heating chamber 4 there is supplied fuel gas 8 and air 9, and the fuel gas 8 is burnt by the chemical reaction with the aid of the catalytic combustion catalyst 6 held in the heating chamber 4. The generated combustion heat is supplied from the heating chamber 4 to the reforming chamber 2 as heat of the reforming reaction.
Thus, generally the reforming reactor 1 is provided with the reforming chamber 2 which has the reforming catalyst 3 and where a reforming reaction is advanced, and the heating chamber 4 which supplies reaction heat to the reforming chamber 2. The conventional plate-shaped reforming reactor 1, shown in FIG. 10, has the heating chamber 4 provided adjacent to the reforming chamber 2 for performing the combustion of the fuel gas 8, but in addition to this conventional technology shown, there is generally known a reforming reactor where a heating medium, for example, high-temperature gas is externally introduced into a heating chamber and where the heat of the high-temperature gas is supplied to a reforming chamber as reaction heat. Furthermore, as another conventional technology, there is also known a reforming reactor where only a reforming chamber is assembled into some other reaction apparatus having a heat generation action and where an excess of heat generated in this reaction apparatus is given to the reforming chamber and utilized as heat of the reforming reaction.
For example, in the fuel cell apparatus shown in Japanese Patent Laid-Open No. 61-24168, a reforming reactor comprising only a plate-shaped reforming chamber is inserted into a fuel cell stacked body, and an excess of reaction heat generated in the fuel cell stacked body is supplied to the reforming chamber as heat of the reforming reaction.
A plate-shaped reforming reactor such as that shown in FIG. 10 is obtainable, for example, by bending and welding a plate-shaped thin metal plate to form the housing of the reforming reactor and suitably putting a reforming catalyst, a catalytic combustion catalyst, and a heat transfer promoting substance into the reforming and heating chambers formed in the housing. As occasion demands, the plate-shaped structure shown in FIG. 10 is made as a unit and a plurality of the same units are stacked to obtain a large capacity reforming reactor.
In the design of a plate-shaped heat exchange type reforming reactor such as this, in order to maintain the temperature distribution of the reaction surface as small as possible and for the reforming reactor to be operated stably for a long period of time, it is extremely important to design the reforming reactor so that at each of the reaction portions a heat balance is achieved between the endothermic heat obtained by the reforming reaction in the reforming chamber 2 and the heat generated by the heating chamber 4.
The reaction rate in the reforming reactor, when for example methane is used for fuel, depends upon the partial pressure of methane and the activity and quantity of the reforming catalyst. Generally, the greater the partial pressure of methane as well as the activity and quantity of the reforming catalyst, the reaction velocity will become greater. In a typical example, the reforming reaction rate of methane is proportional to the product of the partial pressure of methane, the activity of a reforming catalyst, and the quantity of the reforming catalyst, as shown in Equation (2) below.
Reforming reaction rate of methane=k×partial pressure of methane×catalytic activity×quantity of catalyst (2)
where k is a proportional constant.
In the conventional reforming reactor 1, the granular reforming catalysts 3 are equally distributed in the reforming chamber 2 of the reforming reactor 1. At this time, the partial pressure of hydrocarbon, for example, methane contained in the reaction gas is greater at the inlet portion of the reaction gas in the reforming chamber 2 than at the outlet portion of the reaction gas. Therefore, the reforming reaction rate becomes greater at the inlet portion of the reforming chamber 2, as shown in Equation (2). The rapid progress of the reforming reaction causes a concentrated endothermic load, and causes a local temperature drop in that portion. Conversely, at the outlet portion of the reforming reactor, the endothermic quantity by the reforming reaction becomes less and the heat generated by combustion becomes excessive. More specifically, in the conventional example shown in FIG. 10, the heat balance between the endothermic quantity by the reforming reaction and the heat quantity given from the heating chamber tends to be lost particularly at the inlet and outlet portions of the reforming chamber 2. For this reason, the temperature of the inlet portion of the reforming chamber 2 becomes low, dropping to about 400 C. (this inlet portion forms a low- temperature portion), while the outlet portion of the reforming chamber 2 exceeds 700 C. and the heating chamber 4 becomes about 900 C. (this portion forms a high-temperature portion), and consequently, a large temperature distribution or variation occurs in the flow direction of the reaction gas 7.
If a large temperature distribution such as this occurs in the reforming chamber 2, then thermal stresses based on a differential thermal expansion will develop in the reforming chamber to generate cracks in the metal material or welded portions as well as strains in the reforming reactor due to thermal stresses or thermal fatigue. Particularly, in the reforming reactor of the plate-shaped heat exchange type obtained by bending and welding a thin metal plate, the thickness of the raw material is usually thin and the welded portions are also weak in mechanical strength, and consequently, there is a problem from a structural strength point of view in order to perform a long-term operation while allowing a large temperature distribution or a repeated thermal cycle.
In addition, for the reforming catalyst or catalystic combustion catalyst filled in the reforming reactor, there are the following problems. That is, particularly, in the case of the reforming catalyst where magnesia is used as a carrier, there is the danger that the catalytic activity of the catalyst is reduced at the low-temperature portion by the hydrolysis of magnesia. For the catalytic combustion catalyst, a reduction in the catalytic activity by sintering becomes large in the operating temperature range exceeding, for example, 800 C., and consequently, there is the problem that a stable operation cannot be performed over a long period of time.
Utilizing general technology of chemical reaction engineering, it is possible to overcome the aforementioned problems by controlling the reforming reaction rate in the flow direction of the reaction gas and suppressing the reforming reaction rate at the inlet portion of the reforming chamber. More specifically, a more uniform preferable distribution of a reforming reaction is obtainable by suitably controlling the distribution of the filling quantity of the reforming catalyst 3 in the flow direction of the reaction gas or varying the catalytic activity of the reforming catalyst 3 in the flow direction of the reaction gas. However, in order to obtain the aforementioned preferable distribution, it is necessary to vary the activity or filling quantity of the reforming catalyst in the flow direction of the reaction gas to more than ten times. For this reason, a variety of catalysts becomes necessary and the catalyst filling method and structure also become complicated, so a problem arises from the standpoint of manufacturing cost.
For example, when the filling quantity of the catalyst is controlled to optimize the distribution of the reforming reaction, the catalyst filling quantity needs to be reduced, in particular, at the inlet portion of the reaction gas to 1/10 or so of a normal uniform average catalyst filling quantity. However, the reforming catalyst positioned at the inlet portion of the reaction gas is generally liable to become unstable because of the influence of poisoning by impurities such as sulfur contained in the reaction gas or because of the activity reduction due to the oxidation by a large quantity of steam.
FIG. 11 shows as an example the distribution of catalyst activity in the catalyst bed after operation of 5000 to 9000 hours. As shown in FIG. 11, the reforming catalyst positioned at the inlet portion of the reforming reactor tends to lose catalyst activity more than the catalysts held in the other portions does. Therefore, amendment based on the conventional general reaction engineering technology, in which the catalyst filling quantity is considerably reduced at the inlet portion of the reforming reactor to suppress the progress of the reforming reaction, is noticeably subjected to an adverse influence of the activity reduction of the reforming catalyst. That is, even if a predetermined distribution of the reforming rate were obtained at the initial stage of operation, the catalyst activity after a long period of operation would be lost at the inlet portion where the reforming reaction would not be advanced, so a desirable predetermined distribution of the reforming rate, i.e., a predetermined uniform temperature distribution, would not be obtained.
Furthermore, in such a method, if the activity of the reforming catalyst 3 is constantly independent of the passage of time and there is no adverse influence such as the poisoning by sulfur contained in the reaction gas, then the reforming catalyst will function satisfactorily and a desired reforming rate distribution, i.e., a desired temperature distribution will be obtained as designed. However, in practice the activity of the reforming catalyst does not remain constant but varies with time.
FIG. 12 is a diagram showing an example of the change with the passage of time of the activity of the reforming catalyst. The reforming catalyst is usually formed of fine active metal, which is carried on a ceramic carrier with a porous structure. Some activity reduction based on sintering of the fine active metal, cannot be avoided for a long period of time. This conventional technology is so designed that the reforming reaction rate itself on the reforming catalyst is controlled to adjust a reforming reaction rate as well as the resultant reforming rate distribution to a predetermined distribution. Therefore, if the activity of the reforming catalyst changes, then the reaction rate of each portion of the reforming reactor will vary in proportion to the change, and the reforming rate distribution of the reforming reactor will changes. That is, the conventional technology has the fundamental problem on principles that the setting of the reforming rate distribution is largely dependent upon catalyst activity itself and that it is difficult to obtain a fixed stable distribution of a reforming reaction rate, i.e., a stable temperature distribution over a long period of time.
Because the conventional reforming reactor is constructed as described above, the progress of the reforming reaction easily becomes large at the inlet portion through which the reaction gas is introduced, and the reactor becomes structurally complicated and expensive in order to avoid such an excessive progress of the reforming reaction. In addition, even if a predetermined reforming rate distribution, i.e., a predetermined temperature distribution were set, the conventional reactor has the problem that it is difficult to obtain a stable reforming rate distribution, i.e., a stable temperature distribution over a long period of time because of the aforementioned activity reduction.
BRIEF SUMMARY OF THE INVENTION
The present invention has been made in order to solve problems such as described above, and accordingly, an object of the invention is to obtain a reforming reactor which is structurally simple and in which a distribution of a reaction rate of a reforming reaction hardly varies with respect to a variation in the activity of a reforming catalyst and as a result a predetermined reaction rate distribution, i.e., temperature distribution can be obtained over a long period of time, and also in which reactor design is easy and inexpensive.
According to one aspect of the invention, there is provided a reforming reactor comprising: a reforming chamber for reforming a reaction gas into a reformed gas by a reforming reaction; a plurality of gas flow passages disposed in said reforming chamber for guiding said reaction gas from an inlet side toward an outlet side thereof; and reforming blocks provided in a plurality of predetermined sections of each of said gas flow passages and containing reforming catalysts with which said reaction gas, flowing through said gas flow passages, is brought into contact.
According to the above structure, the reforming block has a reforming catalyst enough for a reforming reaction to nearly reach its equilibrium state. The reaction rate of reforming reaction in the reforming block is determined by the flow rate, composition, temperature, and pressure conditions of the reaction gas supplied to the reforming block, and becomes nearly independent of the activity of the catalyst itself. The entire distribution of the reforming reaction rate in the reforming chamber of the reforming reactor is obtained by setting the quantities of reforming reaction at each of a plurality of reforming blocks of the reforming chamber and the arrangement of the reforming blocks. That is, a detailed design of the reactor based on reaction kinetics, including the activity-loss of the reforming catalyst, is not required in designing a distribution of a reforming reaction rate. Basically, the distribution of reforming reaction rate can be accurately and simply designed based on the flow rate of the reaction gas supplied to each reforming block, the equilibrium reforming coefficient, and the arrangement of the reforming blocks. In addition, the distribution of reforming reaction rate, set in this way, is insensitive to a change in the activity of the reforming catalyst, and consequently, a stable reaction rate distribution, i.e., a stable temperature distribution is obtained over a long period of time.
In a preferred form of the invention, said plurality of reforming blocks are distributed in correspondence with a distribution of heat input to said reforming chamber.
According to a structure such as this, the arrangement of the reforming blocks is made in correspondence with the distribution of heat input to the reforming chamber, and the reforming reaction in each reforming block proceeds according to a supply of reaction heat to the reforming chamber. Accordingly, a reforming reactor with a uniform temperature distribution can be obtained.
In another preferred form of the invention,reforming reaction rate at each of said plurality of reforming blocks is determined by controlling a flow rate of reaction gas to each reforming block.
According to a structure such as this, the adjustment of the flow rate of the reaction gas that is supplied to the reforming block is performed by adjusting the flow resistance of the gas flow passage which guides the reaction gas to flow through the reforming block. Accordingly, the adjustment of flow rate can be accurately performed independently of the catalyst filling structure in the reforming block.
In still another preferred form of the invention, a final reforming block is provided at a downstream side of each of said reforming blocks for completion of reforming said reaction gas with the aid of said reforming catalysts.
According to a structure such as this, even in a case where the progress of the reforming reaction in the reforming block is partially insufficient or the reaction gas skips some of the reforming blocks, the reforming reaction can reliably reach its equilibrium state by the action of the final reforming block.
In a further preferred form of the invention, said final reforming block is disposed in a portion of said reforming chamber which operates at a high temperature.
According to a structure such as this, the final reforming block operates at a high temperature which is advantageous for reforming reaction from equilibrium point of view, and a higher conversion of reforming reaction is obtainable.
In a further preferred form of the invention, said reforming reactor is comprising only a plate-shaped reforming chamber and is inserted into a fuel cell stacked body.
According to a structure such as this, the reforming block holds the reforming catalyst directly in the gas flow passage. Accordingly, an extra space for holding the reforming catalyst is unnecessary, the contact between the reaction gas and the catalyst can be sufficiently assured, and a sufficient reaction is obtainable with a compact shape.
In a further preferred form of the invention, said fuel cell is a molten carbonate type fuel cell.
According to a structure such as this, the final reforming block holds the reforming catalyst directly in the gas flow passage. Accordingly, an extra space for holding the reforming catalyst is unnecessary, the contact between the reaction gas and the catalyst can be sufficiently assured, and a sufficient reaction is obtainable with a compact shape.
In a further preferred form of the invention, said reforming blocks are constructed by holding said reforming catalyst in said gas flow passages to thereby form a partition plate in said gas flow passage so that said gas flow passage is partitioned into a first area in which said reforming catalyst is disposed, and a second area through which said reaction gas flows.
According to a structure such as this, the reforming catalyst in each reforming block is held directly on one side of the gas flow passage. Accordingly, the reaction gas can flow through the uniform cross section of the gas flow passage, the pressure drop can be reduced, and a distribution ratio of gas to each reforming block can be accurately and easily set. Furthermore, the gas flow passage structure and the catalyst filling structure can be separately designed and manufactured, and a reforming reactor which is easy to be designed and manufactured is obtainable.
In a further preferred form of the invention, said final reforming block is constructed by holding said reforming catalyst in said gas flow passage in such a way that said reforming catalyst occupies part of the cross section of each said gas flow passages.
According to a structure such as this, the reaction gas can flow through the uniform cross section of the gas flow passage, the pressure drop can be reduced, and a distribution ratio of gas to each reforming block can be accurately and easily set.
In a further preferred form of the invention, said partition plate has at least a permeable portion for allowing permeation of said reaction gas between adjacent ones of said gas flow passages.
According to a structure such as this, the contact between the reaction gas and the reforming catalyst becomes easy, and the afore-mentioned advantages can be further enhanced.
In a further preferred form of the invention, said gas flow passages are formed by a corrugated plate having opposite surfaces and a pair of impermeable plates attached to the opposite surfaces of said corrugated plate.
According to a structure such as this, a plurality of gas flow passages which are materially separated from one another can be set only by constituting both surface of the corrugated plate by means of impermeable plates. Accordingly, there is obtainable a reforming reactor which is structurally simple and is inexpensive.
In a further preferred form of the invention, said gas flow passages are laminated in layers by separation plate means.
In a further preferred form of the invention, each of said layers is partitioned into a reforming catalyst layer and a gas flow passage layer by partition plate means having a permeable portion.
In a further preferred form of the invention, each of said layers has gas flow passages which are obtained by dividing a gas flow space on each layer in the right direction to the direction of lamination.
In a further preferred form of the invention, positions of said reforming blocks in adjacent ones of said divided gas flow passages are shifted from each other in a flow direction of said reaction gas.
According to a structure such as this, in the reforming chamber of the reforming reactor comprising a multilayer structure, a plurality of gas flow passages separated from one another can be easily realized with a simple structure. In addition, the degree of freedom of the disposition of the reforming blocks is large and an ideal distribution of reforming reaction rate can be easily achieved.
Furthermore, a plurality of spaces which hold reforming catalysts constituting a plurality of reforming blocks, which were lead from a plurality of mutually separated gas flow passages contained in the same gas flow passage layer, can be collected as a single reforming catalyst layer. As a result, a catalyst filling operation becomes easier. Moreover, the setting of the disposition of the reforming blocks can be performed, for example, by providing a partition plate between the gas flow passage layer and the reforming catalyst layer and setting a permeable area of this partition plate, and consequently, an ideal setting of the reforming blocks can be easily achieved.
Furthermore, the two-dimensional arrangement of reforming blocks is possible in one layer, and an ideal distribution of reforming reaction rate can be achieved even in a compact reformer.
In a further preferred form of the invention, positions of said reforming blocks in two or more of said layers are shifted from each other in a flow direction of said reaction gas.
According to a structure such as this, the positions of the reforming blocks in each layer are shifted from each other in the reforming chamber comprising a multilayer structure. Accordingly, the dispersion of the reforming reaction can be easily and accurately achieved, and achievement of an ideal distribution of reforming reaction rate, i.e., temperature distribution becomes possible.
In a further preferred form of the invention, at least such portions of said separation plate means that are located backward of the reforming block in the flow direction of said reaction gas have permeability.
According to a structure such as this, in the reforming chamber comprising a multilayer structure, the flow and mixing of the reaction gases between gas flow passages are possible in the rear of the reforming block in the flow direction of the reaction gas. Therefore, even if the progress of the reforming reaction were insufficient at some of the reforming blocks, the progress of the reforming reaction would be possible by other reforming blocks at the backside. In addition, the setting of various kinds of reforming distributions becomes possible with a compact layer structure, and a compact and highly reliable reforming reactor can be obtained.
In a further preferred form of the invention, a single reforming catalyst layer is shared between a set of adjacent layers of said layers.
According to a structure such as this, a plurality of reforming catalyst layers can be collected into a single layer, and an ideal distribution reforming reaction rate can be achieved with a compact and inexpensive structure.
BRIEF DESCRIPTION OF THE DRAWINGS
The above and other objects and advantages will become apparent from the following detailed description when read in conjunction with the accompanying drawings wherein:
FIG. 1(a) is a side sectional view showing the structure of the reforming chamber of a reforming reactor of a first embodiment of the present invention;
FIG. 1(b) is a plan view showing the structure of the reforming chamber of a reforming reactor of FIG. 1(a);
FIG. 2 is a sectional view showing an example of the structure of the reforming blocks provided in the reforming chamber of the reforming reactor of the first embodiment;
FIG. 3 is a perspective view showing another example of the structure of the reforming blocks provided in the reforming chamber of the reforming reactor of the first embodiment;
FIG. 4 is a diagram showing the relationship between a catalyst loading and a methane conversion, which is necessary in determining the catalyst loading of the reforming blocks in the reforming reactor of the first embodiment;
FIG. 5 is a diagram showing an example of a distribution of methane reforming rate distribution along the direction of the reaction gas in the reforming chamber of the reforming reactor of the first embodiment;
FIG. 6 is a diagram showing an example of an endothermic density distribution along the direction of the reaction gas in the reforming chamber of the reforming reactor of the first embodiment;
FIG. 7 is a sectional view showing the structure of the reforming chamber of a reforming reactor of a second embodiment of the present invention;
FIG. 8(a) is a side sectional view showing the structure of the reforming chamber of a reforming reactor of a third embodiment of the present invention;
FIG. 8(b) is a plan view showing the structure of the reforming chamber of a reforming reactor of FIG. 8(a);
FIG. 9(a) is a side sectional view showing the structure of the reforming chamber of a reforming reactor of a fourth embodiment of the present invention;
FIG. 9(b) is a plan view showing the structure of the reforming chamber of a reforming reactor of FIG. 9(a);
FIG. 10 is a sectional view of a conventional reforming reactor;
FIG. 11 is a diagram showing an example of the distribution of catalyst activity in the catalyst layer after a continuous operating test; and
FIG. 12 is a diagram showing an example of the change with the passage of time of the activity of the reforming catalyst.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
First Embodiment
An embodiment of the present invention will hereinafter be described with reference to the accompanying drawings. FIG. 1(a) shows in cross-section a reforming chamber 2 of a reforming reactor constructed in accordance with the principles of the present invention, and FIG. 1(b) shows the flow of a reaction gas in reaction gas flow passages 12b and the position of arrangement of reforming blocks of the reforming chamber shown in FIG. 1(a).
In FIG. 1, an arrow 7 indicates a direction along which the reaction gas is supplied to and exhausted from the reforming chamber 2. In the reforming chamber 2 a plurality of reaction gas flow passages 12 are defined by a plurality of separation plates 11. Reforming blocks 13a to 13f each holding a reforming catalyst 3 in the interior thereof are provided in the reaction gas flow passages 12, as shown in FIG. 1(a). In the outlet portion of each of the reaction gas flow passages 12, there is a final reforming block 14, which holds the reforming catalyst 3 in the interior thereof.
The oblique lines in FIG. 1(b) indicate the positions where the reforming blocks 13a and 13b and the final reforming block 14 are arranged. Within the reforming chamber 2 of the reforming reactor in this embodiment, there are provided three reaction gas passages 12a, 12b, and 12c between which the reaction gas cannot come and go, as shown in FIG. 1(a). On the partial section of the reaction gas flow passage 12a, there are provided the reforming blocks 13a and 13b and the final reforming block 14. On the partial section of the reaction gas flow passage 12b, there are provided the reforming blocks 13c and 13d and the final reforming block 14. On the partial section of the reaction gas flow passage 12c, there are provided the reforming blocks 13e and 13f and the final reforming block 14.
Note that the arrows shown by solid lines in FIG. 1(b) indicate the directions of the reaction gas which flows through the reforming chamber.
FIGS. 2 and 3 illustrate an example of the structure of the reforming block 13 for holding the reforming catalyst 3 on the partial section of the interior of the reaction gas flow passage 12. In the reforming block in FIG. 2, the reforming catalyst 3 is provided in a partial area so as to occupy a portion of the cross sectional area of the reaction gas flow passage 12. An area, which is not occupied by the reforming catalyst 3 and through which the reaction gas flows, forms a gas flow passage space 15. The reaction gas flow passage 12 is partitioned by a permeable partition plate 16 into the space for holding the reforming catalyst 3 and the gas flow passage space 15. In FIG. 3, the partition plate 16 is shown as being formed by a corrugated plate and having aperture portions. Although, in FIG. 3, reaction gas flow passages which are provided before and after the reforming block 13 are omitted, the reaction gas flow passage can be formed by the same corrugated plate as the partition plate 16, and the reforming catalyst is not filled into the reaction gas flow passage.
Next, the operation of the first embodiment of the present invention will be described with reference to FIG. 1. The reforming reactor shown in FIG. 1 is a plate-shaped reforming reactor and corresponds to the reforming chamber of the reforming reactor shown in FIG. 10 as prior art. In FIG. 1 there is omitted a heating chamber which is adjacent to the reforming chamber.
Initially, a description will be made of the progress of the reforming reaction.
The reaction gas mainly composed of a hydrocarbon or an alcohol is introduced into the reforming chamber 2, then is dispersed by a distributor 20, and thereafter is distributed into the reaction gas flow passages 12a, 12b, and 12c in accordance with a predetermined ratio. The reaction gas distributed to the reaction gas flow passage 12b flows through the reaction gas flow passage 12b without reacting for a while. Then, if the reaction gas reaches the reforming block 13a, only part of the reaction gas (in the embodiment of FIG. 1, about 1/2 of the reaction gas supplied to the reaction gas flow passage 12b) will be reformed by the function of the reforming catalyst 3 of the reforming block 13a until it nearly reaches its equilibrium state.
The reforming block 13a is dispersed and disposed in a direction perpendicular to the flow direction of the reaction gas, as shown in FIG. 1(b). Part of the reaction gas (in the embodiment of FIG. 1, about 1/2 of the reaction gas supplied to the reaction gas flow passage 12b), which flows through the reaction gas flow passage 12b, flows through the reaction gas flow passage 12b without contacting with the reforming catalyst of the reforming block 13a. For this reason, part of the reaction gas flows through the reaction gas flow passage 12b without reacting, and is reformed by the reforming catalyst 3 of the reforming block 13b separately provided on the downstream side of the passage 12b until it nearly reaches its equilibrium state. With this, because the reaction gas supplied to the reaction gas flow passage 12b flows through the reforming block 13a or 13b, it is reformed until it nearly reaches the equilibrium state. The reaction gas further passes through the final reforming block 14, which is provided at the outlet portion of the reforming chamber 2. The reaction gas is then reformed completely until the equilibrium state, and thereafter is exhausted from the outlet portion to the outside of the reforming chamber 2.
The reaction gas supplied to the reaction gas flow passage 12c, as in the reaction gas flow passage 12b, passes through the reforming blocks 13c and 13d provided so as to be shifted from each other in the flow direction of the reaction gas and is reformed until nearly reaching the equilibrium state. The reaction gas further passes through the final reforming block 14 and completion of reforming reaction is secured. The reaction gas supplied to the reaction gas flow passage 12a is likewise processed in a similar manner.
The reforming blocks 13a to 13f, as shown in FIGS. 2 and 3, hold within the reaction gas flow passage 12 the reforming catalyst 3 so that the catalyst 3 occupies part of the cross section area of the flow passage. The area of the cross section of the flow passage which is not occupied with the reforming catalyst 3 functions as the gas flow passage space 15. The space for holding the reforming catalyst 3 and the gas flow passage space 15 are partitioned by the partition plate 16 having aperture portions 16a. This partition plate 16 has permeability due to the existence of the aperture portions 16a, and the reaction gases in both the spaces can come and go between the spaces. In a reformer structure such as that shown in FIGS. 2 and 3, the reaction gas selectively flows through the gas flow passage space 15 where the resistance for gas-flow is low. The reaction gas flowing through the gas flow passage space 15 comes in contact through the aperture portions 16a of the partition plate 16 with the reforming catalyst 3 held in the reforming block 13, and is reformed.
For the hold-structure of the reforming catalyst 3 in the reforming blocks 13a to 13f, consider the two following cases. First, there is a case where the reforming catalyst 3 is held in the interior of the reaction gas flow passage 12 and serves as a reforming block. In this case, the structure of the reforming block may be the same as the structure of the reaction gas flow passage before and after the reforming block, except that the reforming block holds the reforming catalyst, and the reforming chamber can be constructed with a minimum number of parts. For example, the reforming block in the reaction gas flow passage before and after the reforming block can be constructed with the same corrugated plate, as shown in FIG. 3. In such a case, in the reaction gas flow passage the corrugated plate functions as a flow passage constituting material. In the reforming block, the corrugated plate functions as the flow passage constituting material and the partition plate 16. In addition, in this case an extra space for holding the reforming catalyst is not needed except for the reaction gas flow passage, so the reactor becomes compact. Furthermore, the contact between the reaction gas flowing through the reforming block and the reforming catalyst is satisfactorily held, and sufficient reforming reactivity is obtained.
As a second case, there is a case where the reforming catalyst 3 is held in one side portion adjacent to the reaction gas flow passage 12 and functions as a reforming block. The case will be described later in FIG. 8. In this case, even in the reforming block, the gas flow passage through which the reaction gas flows, is the same as the reaction gas flow passage before and after, and pressure drop can be minimized because the reforming catalyst is not held. In addition, there occurs less variation of the pressure drop among the reforming blocks resulting from the inaccuracy of filling of the reforming catalyst, and the distribution of gas to the reforming block can be performed with accuracy. Furthermore, the gas flow passage structure and the catalyst filling structure can be separately designed and manufactured, the degree of freedom of the design is large, and therefore an easy structure can be provided from the aspect of manufacturing.
For example, in the example of FIG. 8 described later, a plurality of hold spaces for reforming catalyst belonging to a plurality of reforming blocks can be collected into a single reforming catalyst layer and filled. As a result, the catalyst filling operation can be considerably simplified and an ideal distribution of reforming reaction can be readily achieved.
Furthermore, in the case where the reforming catalyst is held in the interior of the reaction gas flow passage and functions as a reforming block, the reforming catalyst may occupy the entire cross section of the gas flow passage in place of the structure of FIG. 2 where the reforming catalyst occupies only part of the cross section of the gas flow passage. More specifically, the reforming catalyst 3 is filled in the entire cross section of the flow passage by a general filling method, and for example, the filling structure and the reforming block, shown in the reforming chamber of a reforming reactor of FIG. 10, may be obtained. In a method such as this, the reaction gas flows through the small gaps as a reaction gas flow passage formed between the filled particles of reforming catalyst.
In the case where the reforming catalyst is held in such a gas flow passage, there are two cases, the case where part of the cross section of the gas flow passage is occupied and the case where the entire cross section of the gas flow passage is occupied. Both structures can be utilized from the standpoint of the achievement of avoiding the concentrated reforming reaction at the entrance and the stable operation, which are the main objectives of the present invention. If both structures are compared, the structure where part of the cross section is occupied with catalyst will have the following improved features over the structure where the entire cross section is occupied. First, the pressure drop in the flow passage becomes small. Second, problems, such as the variation of the pressure drop in the flow passage resulting from an inevitable variation of the filling density of the catalyst particles and the necessity of readjusting the pressure drop resulting from the above, come to disappear. Third, the design of the flow resistance of the gas flow passage is free from the filling quantity and the shape of the reforming catalyst. Therefore designing and adjustment of the flow resistance, necessary for determining the flow rate of the reaction gas to each reforming block, can be easily and quantitatively performed with a degree of freedom.
The partition plate constituting a reforming block such as this may be a plate-shaped porous plate such as that shown in FIG. 2, or a corrugated fin comprising a corrugated plate of the multi-entry type which is widely used in heat exchangers, such as that shown in FIG. 3. In the case of the corrugated plate of the multi-entry type, there is the advantage that the contact area between the reforming block 13 and the gas flow passage space 15 can be increased, the reforming block can be made thin, and the catalyst filling quantity can be made uniform by standardizing the filling quantity of the catalyst that is filled in the aperture of the corrugated plate.
As for the reforming reactivity of the reforming block, the reforming catalyst 3 is held so that each of the reaction gases supplied to each reforming block is reformed to near the equilibrium state. The necessary quantity of the reforming catalyst or the length of the reforming block is computed by a conventional reaction engineering technique. For instance, FIG. 4 shows an example of the relationship between a relative catalyst loading and methane conversion at the outlet of reforming block. As shown, as the catalyst loading increases, the methane conversion comes to close to the equilibrium methane conversion (0.9 in this case). It is preferable in this embodiment that in the reforming block the reaction gas is to be reformed up to the vicinity of the equilibrium state. For example, in the operating conditions shown in FIG. 4, the filling quantity of catalyst is set so that the methane conversion at the outlet of the reforming block becomes 0.8 or more.
Now, an example of the distribution of methane conversion along the reaction gas flow direction in the aforementioned embodiment is shown in FIG. 5. As for the operating conditions, pressure is atmospheric pressure, temperature is 650 C., and a steam-methane ratio is 3.0. In FIG. 5, position P1 indicates the inlet of the reforming chamber 2, and position P10 indicates the outlet of the reforming chamber 2. Positions P2 to P8 indicate the start positions of the reforming blocks 13a to 13f and the final reforming block 14, respectively. Position P9 indicates the end position of the final reforming block 14. The reaction gas supplied to the reforming chamber 2 flows from the inlet portion of the reforming chamber 2 to the outlet portion, but the reforming reaction does not start in the vicinity of the inlet portion because the reforming catalyst is not held in the inlet portion. When viewed in the flow direction of the reaction gas, the reforming reaction will start if the reaction gas, which is distributed to the reaction gas flow passage 12b and passes through the reforming block 13a, reaches the position P2 The reaction gas, which is distributed to the reaction gas flow passage 12b and passes through the reforming block 13b, will start the reforming reaction if the reaction gas reaches the position P3 . Thereafter, the reaction gas distributed to the reaction gas flow passage 12c starts the reforming reaction at the positions P4 and P5 , and the reaction gas distributed to the reaction gas flow passage 12a starts the reforming reaction at the positions P6 and P7 . Methane distributed and supplied to the reforming blocks 13a to 13f is reformed at each reforming block to nearly the equilibrium state. Finally, the reaction gas passes through the final reforming block 14 and is secured to be reformed to the equilibrium state. The equilibrium methane conversion at the same conditions is about 0.9.
Thus, this embodiment has been designed so that a predetermined distribution of reforming reaction is obtained by providing a plurality of reforming reaction areas of the reforming blocks in the reforming chamber of the reforming reactor and fixing the amount of reforming reaction at each reforming reaction area. In this embodiment, in order to assure the degree of freedom of the layout of a plurality of reforming blocks, the reforming chamber is formed into a multilayer structure. In addition, as a method of fixing the quantity of the reforming reaction which proceeds at each reforming reaction area, a sufficient reforming catalyst is held in the reforming reaction areas and a predetermined quantity of reaction gas is independently supplied and is reformed at the reforming reaction areas to nearly the equilibrium state. With this, the reactor is designed so that distribution of reforming reaction can be accurately set and a stable distribution can be obtained for a long period of time. It is important in a design such as this to (1) hold reforming catalyst enough for reaction gas to reach a substantial equilibrium state, (2) accurately distribute and supply reaction gas to each reforming block, and (3) control reaction gas so as not to react at a place other than allocated reforming blocks.
Initially, for the first point, a necessary quantity can be easily determined by experimentation or computation, as previously shown in FIG. 4. If the catalyst loading is enough for a reforming reaction to go to a substantial equilibrium state, there would be little influence on methane conversion even if the filling quantity fluctuated to some degree. Also, even if reforming catalyst were filled to more than necessary, there would not be any particular problem. In the conventional technique, the conversion profile itself of the reforming reaction has a direct influence on a temperature distribution therefore not only the methane conversion at the exit of the reforming chamber must nearly reach its equilibrium, but also a predetermined distribution of methane conversion must be obtained in order to achieve a flat temperature distribution. Therefore, a highly sophisticated technology is required for determining a reaction profile. In the present invention, distribution of the reforming reaction is nearly determined by both the position of the reforming block and the distribution of reaction gas to each reforming block. The distribution of methane conversion in each reforming block is not so important in determining the distribution of reforming reaction in the entire reforming reactor and it does not become the limiting conditions of a design. Therefore, in each reforming block a rapid progress of reforming reaction is allowed at the inlet portion, and a long-life design by holding enough catalyst and a simple reactor design are possible.
For the second point, this problem is solved by introducing the reforming block 13 by the structure where the hold space for reforming catalyst and the gas flow passage space 15 are separated each other as previously shown in FIG. 2. In the conventional packed bed design because the reforming catalyst is uniformly filled in the entire flow space, the flow resistance mainly depends upon the shape and filling quantity of the catalyst and it is difficult to freely adjust only the flow resistance. In the embodiment shown in FIG. 2, the flow resistance of the reforming block depends only upon the structure of the gas flow passage space and is independent of the filling of the catalyst.Therefore the adjustment of flow resistance has no effect on the reforming reaction, and the flow resistance can be freely adjusted. More specifically, the adjustment of the flow resistance is possible by adjusting the height of the cross section of the reaction gas flow passage. This adjustment does not have any influence directly on the quantity of the reforming catalyst held in the catalyst hold space. In addition, for example, in the case where the reaction gas flow is formed with a corrugated plate, the adjustment of the flow passage resistance is also possible by adjusting the shape of the corrugated plate at each of the reaction gas flow passages. Furthermore, the thus set flow passage resistance is not influenced by the variation of the catalyst filing at the catalyst hold space, and an accurate design of the flow resistance is possible. Moreover, for the catalyst filling, check of variation of pressure drop and a filling readjustment operation such as those required for the conventional reforming reactor becomes unnecessary.
For the third point, the present invention has been designed such that the reaction gas flow passages for introducing reaction gas into the reforming blocks are provided independent of each other and that the reaction gas passing through one reaction gas flow passage does not come in contact with the reforming catalyst of another reforming block. The operating temperature of the reforming reactor is as high as 600 to 800 C., and the diffusion of gas is quick. In a case where an aperture portion which cannot be neglected exists in part of each reaction gas flow passage which introduces reaction gas, particularly in a case where the area of aperture portion is large and aperture portion is adjacent to the reforming catalyst of another reforming block, methane in reaction gas diffuses or passes through the aperture portion and advances its reforming reaction with the aid of the reforming catalyst of a neighboring reforming block. In such a case, the advance of the reforming reaction secondarily produced renders the design of the methane conversion profile inaccurate, or accurately predicting the progress of the reforming reaction secondarily produced is additionally required in setting the distribution of reforming reaction. That is, consideration for diffusion and gas flow becomes necessary at the time of design, in addition to consideration for reforming reaction rate. Consequently, a more complicated design becomes necessary.
On the other hand, for example, in the embodiment shown in FIG. 1, where the reaction gas passages 12a, 12b, and 12c are impermeable to one another, there is no such problem of reforming reaction secondarily produced. Therefore an easy and accurate design is possible. Also, for example, in the reaction gas flow passage 12b, there is a possibility of such a secondary reforming reaction to advance, in the reaction gas flow passage for introducing reaction gas to the reforming block 13b, shown in FIG. 1(a). In this case, there is no problem such as this if the reaction gas flow passages for introducing reaction gas to the reforming blocks 13a and 13b are partitioned and sealed at the boundary area by an impermeable material. In addition, for instance, if the reaction gas flow passage 12b is formed with a corrugated plate with no apertures where no gas exchange takes place between the gas channels of the upper side and lower side of the corrugated plate, then there will be no exchange of reaction gas in the lateral direction of the reaction gas flow, and no problem such as this will occur.
On the other hand, in the case where a corrugated plate with aperture portions shown in FIG. 3 is used as the partition plate 16, part of the reaction gas passing through the reforming block 13b proceed a secondary reforming reaction by the aid of the reforming catalyst positioned at the side-end of the reforming block 13a before reaching the reforming block 13b. More particularly, gas exchange partially takes place at the boundary between the reforming block 13a and the reaction gas flow passage 12b for introducing reaction gas to the reforming block 13b. Because of this gas exchange, a secondary reforming reaction advances. An estimated width of the reaction gas flow passage 12b for introducing reaction gas to the reforming block 13b is about 10 to 15 cm by way of example, while the pitch of the corrugation of corrugated plate is about 0.2 to 0.3 cm. In this case, about 10 percent of the reaction gas which passes through the reaction gas flow passage 12b leading to the reforming block 13b is practically equivalent to passing through the reaction gas flow passage 12b leading to the reforming block 13a from the viewpoint of contact between catalyst and reaction gas. If the quantity of the reforming reaction secondarily produced is such an amount as mentioned above or less, this problem can be sufficiently coped with by considering the quantity of the reforming reaction which is secondarily produced in determining the distribution of reaction gas to the reforming blocks 13a and 13b. Therefore it is can be said that the reaction gas flow passages is practically separated from each other as far as secondary reforming reaction is as low as the above.
Also, speaking from a point of view such as this, the reaction gas flow passages do not need to be designed so that they are separated from each other by an impermeable material, after the reforming reaction is nearly completed by the corresponding reforming block. Even if the reaction gas contacted with the reforming block of an adjacent reaction gas flow passage often the reforming reaction, the reaction gas would have no influence on the reforming reaction distribution because the reforming reaction has been nearly completed. In a structure such as this, even in a case where the advance of the reforming reaction is insufficient at one reforming block for some reason, the reaction gas has a chance to contact again with the reforming catalyst of another reforming block and therefore the achievement of a sufficient reforming reaction can be performed with reliability. Likewise, the reaction gases passing through the reaction gas flow passages may be mixed after main reforming reaction is completed, and then the mixed gas may be supplied to a single finishing reforming block.
Considering the temperature distribution of the reforming reactor, it is important, for example, in the plate-shaped reforming reactor shown in FIG. 1 that the distribution of endothermic heat in the reforming chamber and the distribution of generated heat in the heating chamber are balanced. The distribution of endothermic heat in the gas flow direction in the reforming chamber is determined by considering the distribution of reforming reaction and the heat of the reforming reaction.
The relative-value histogram of the distribution of endothermic heat in the reaction gas flow direction of the embodiment shown in FIG. 1 is shown in FIG. 6. The average value of the endothermic heat density, obtained by dividing the total endothermic heat of the reforming reaction by the total laminated area, is shown by a broken line. As shown, in this embodiment, after distribution of generated heat density is postulated at the heating side, distribution of endothermic heat density in the reaction gas flow direction is obtained at the reforming side so that it is balanced with the distribution of generated heat density. Specifically, a design is made so that a predetermined endothermic density distribution, i.e., reforming reaction distribution is obtained by adjusting the structure of each reforming block and adjusting the distribution of the reforming blocks in the plane of lamination.
For example, the reforming blocks 13a and 13b are set longer in the reaction gas flow direction than the reforming blocks 13c and 13d, and the average density of endothermic heat in these areas is made small. Also, for example, the reforming blocks 13e and 13f are set far shorter in the reaction gas flow direction than the reforming blocks 13c and 13d, and the average density of endothermic heat is made large. This can also be achieved by another means, for example, by making the flow rate of the reaction gas flowing through the reaction gas passage 12a largest in accordance with the endothermic density distribution on the heating side and making the flow rate of the reaction gas flowing through the reaction gas passage 12b least. Specifically, this can be done by suitably adjusting the flow resistance or cross section area of the reaction gas or reforming block.
In addition, in the reaction gas flow passages 12a, 12b, and 12c, the regions filled with catalyst have been provided so as to be shifted in a zigzag manner in the flowing direction of the reaction gas at each flow passage. With this, the advance of the reforming reaction can be shifted in the reaction gas flow direction, so the endothermic heat density can be more finely controlled. This arrangement is nearly the same as the case where the reaction gas passage is divided into 6 layers and in each layer the reforming reaction areas are shifted. In the embodiment of FIG. 1, nearly similar advantages are obtained with only a three-layer structure, and consequently, the reforming reactor can be made compact and inexpensive.
In FIG. 6, the reason that the endothermic heat density is set to zero between the inlet area positions P1 and P2 of the reaction gas is that there was supposed a case where the heat supplied from a heating side is all used in the inlet area to preheat the reaction gas and that as a result reaction heat enough to advance the reforming reaction does not remain. In addition, the reason that the distribution of endothermic heat is increased in sequence from the position P2 to the position P8 is that in this embodiment there was assumed a case where the heat supplied from the heating chamber to the reforming chamber is increased in sequence from the position P2 to the position P8.
In either case, from the point of view that the temperature distribution of the reforming reactor is made uniform, the obtained distribution of endothermic heat is designed so as to match with a distribution of combustion heat obtained at the heat giving side, i.e., by the combustion in the heating chamber or by the transported heat from high-temperature gas fluid in the heat giving side. Or, in the case of a reactor where only the reforming chamber is incorporated and utilizes the excess heat generated at the other portion of a reactor; for example, in the case of a reforming reactor which is incorporated into a fuel cell apparatus and where the reforming reaction is advanced at the reforming chamber by making use of the aforementioned excess heat, the distribution of endothermic heat at the reforming chamber is designed so as to nearly match at an adjacent interface with the distribution of an excessively generated heat that is utilized. As a result, a more uniform temperature distribution is obtained in the reforming reactor, and the reforming reactor and the catalyst put in the reforming reactor can be stably operated for a long period of time.
It is preferable that the final reforming block 14 is provided at the highest-temperature portion of the reforming chamber 2. In the embodiment shown in FIG. 1 it is assumed that the outlet area of the reaction gas is the highest point of the temperature distribution. As an operating temperature becomes higher, the equilibrium conversion becomes higher. Therefore, the reaction gas, nearly reformed to the equilibrium state in the upstream reforming blocks 13a to 13f, passes through the final reforming block 14 and is further reformed. In addition, the part of the reaction gas which has not been completely reformed to the equilibrium state or the reaction gas which has skipped the catalyst layer for some reason passes through the final reforming block 14 again, and so the reforming reaction is reliably advanced.
The reforming reactor of the embodiment functions as follows with respect to the stability of the reforming ability. As for the progress of the reforming reaction at each reforming block, the reaction gas is designed to be reformed to the equilibrium state. Because of the reaction condition such as this, the progress of reforming reaction at the reforming block 13 is insensitive to a small change of the activity of the reforming catalyst 3. The amount of reforming reaction is mainly determined by the flow rate of the reaction gas that is supplied to the respective reforming blocks. Therefore, for the distribution of the entire reforming reaction at the reactor plane, the distribution is mainly determined by the flow passage structure of the reaction gas and the disposition of the reforming blocks on the plane, and is stable in principle because it does not involve a reaction step cause which varies with the passage of time.
In the respective reforming blocks, the distribution of the reforming reaction in the flow direction of the reaction gas changes with the passage of time, as in the conventional example. But, the degree of change is far smaller compared with the conventional example where the amount of catalyst is reduced and adjusted on purpose in order to suppress the advance of the reforming reaction. In addition, the change with the passage of time of the distribution of reforming reaction in the embodiment is mainly a change in a limited range like a change within the reforming block, and therefore the influence which the change has on the distribution of reforming reaction at the entire plane of the reactor is small. The entire distribution of reforming reaction has been roughly determined by the distribution of the reaction gas to each reforming block and the disposition of the reforming blocks.
In addition, in the embodiment the introduction portion of the reaction gas to the catalyst layer is scattered over the entire plane of the reactor. Therefore the influence which the poisoning of the catalyst has on the distribution of reforming reaction is also scattered over the entire laminated area, and there is eliminated the drawback that a bad influence is concentrated on the inlet portion of the reaction gas, found in the conventional reactor.
Second Embodiment
In the aforementioned first embodiment, three reaction gas flow passages 12a, 12b, and 12c are separated from each other and provided immediately after the inlet of the reforming chamber of the reforming reactor, and the reaction gas flow passages introduce reaction gases into the corresponding reforming blocks without mixing the reaction gases together. However, it is not always necessary that the reaction gas flow passages are completely separated over the entire length from the inlet of the reforming chamber to the outlet. In the reforming chamber 2, partially reformed reaction gases may be mixed together on the way and introduced into the reaction gas flow passages and reforming blocks provided downstream of the reforming chamber.
A second embodiment of the present invention, which has a mixing section in the process where reaction gas advances its reforming reaction, is shown in FIG. 7. FIG. 7 is a sectional view showing the structure of a reforming chamber constituted by two upper and lower reaction gas flow passages and reforming blocks. In this embodiment, the reaction gas is distributed at the inlet portion to reaction gas flow passages 12a and 12b. The reaction gas supplied to the reaction gas flow passage 12a is reformed by reforming blocks 13a and 13b. The reforming blocks 13a and 13b, as with the reforming blocks 13a and 13b of the embodiment previously shown in FIG. 1, are shifted from each other and disposed in the reaction gas flow passage 12a. The reaction gas distributed to the reaction gas flow passage 12b passes through the reaction gas flow passage 12b without reaction. The reaction gases exhausted from the reaction gas flow passages 12a and 12b are mixed at the mixing section 18 and then are distributed and supplied to reaction gas flow passages 12c and 12d provided downstream of the flow passages 12a and 12b. The reaction gas distributed to the reaction gas flow passage 12c is further reformed at a reforming block 13c, and the reaction gas distributed to the reaction gas flow passage 12d is further reformed at a reforming block 13d. Thereafter, the reformed reaction gases are exhausted from the reforming chamber.
While in the embodiment of FIG. 7 the reforming chamber has a two-layer laminated structure, the chamber may be divided into three reforming blocks (13a+13b), 13c, and 13d in the flow direction of the reaction gas. This embodiment can establish nearly the same distribution of reforming reaction as the embodiment of FIG. 1 comprising a three-layer laminated structure. The embodiment of FIG. 7 can obtain a reforming reactor which is thinner and more compact.
Thus, in the reforming reactor which has a reforming chamber of a multilayer structure that is constructed by stacking a plurality of layers, reaction gases are mixed on the downstream side of the reforming block provided on the most upstream side by means of the permeable portion of the interlayer separation plate, and further, the mixed gas is supplied to the reaction gas flow passage and the reforming blocks, which are provided downstream of the permeable portion. In this way, various kinds of reforming distributions can be achieved with a thinner layer structure.
Third Embodiment
While in the first embodiment a plurality of reforming blocks each holding a reforming catalyst have been provided in the reaction gas flow passages in a scattered manner, a reforming catalyst may be held on one side of the reaction gas flow passage and constitute a reforming block, as shown in FIG. 8.
FIG. 8 illustrates a reforming chamber comprising a single layer, which is constituted by a gas flow passage layer including a plurality of gas flow passages 12 separated from one another, a reforming catalyst layer 17 holding a reforming catalyst 3 provided on one side of the gas flow passage layer, and a partition plate 16 interposed between the gas flow passage layer and the reforming catalyst layer 17 for partitioning both layers. In FIG. 8, reaction gas supplied is introduced into a plurality of the gas flow passages 12 separated from one another and is supplied to reforming blocks 13a, 13b, and 13c. In the reforming block 13, the reaction gas contacts with the reforming catalyst 3 through a permeable partition plate 16a and advances a reforming reaction. In this embodiment, along the flow direction of the reaction gas, first the reforming reaction is started at the reforming block 13a and then the reforming reaction advances in sequence at the reforming blocks 13b and 13c. Finally, the reforming reaction is secured to advance to the equilibrium state at a final reforming block 14. The reason that, in this embodiment, the areas of the reforming blocks 13a and 13b are extended up to the area of the final reforming block 14 is for assuring a complete advance of the reforming reaction in both the reforming blocks.
In addition, in the structure shown in this embodiment, the positions of a plurality of reforming blocks 13a, 13b, and 13c are not directly related to the filling position of the reforming catalyst 3, and correspond directly to the position of the permeable portion 16a of the partition plate 16. The impermeable portion 16b of the partition plate 16 corresponds to the reaction gas flow passage 12 where the reforming reaction does not advance. That is, for the filling of the reforming catalyst, the reforming catalyst can be uniformly filled in an area such as including at least an area of arrangement of a plurality of reforming blocks, and the reforming catalyst layer can be formed. If the partition plate is made porous only at an area where the reforming block is to be disposed, that portion can be regarded as a reforming block. If the partition plate has an impermeable portion 16b at a position facing the reaction gas flow passage 12 in order to prevent the advance of the reforming reaction, then whether the reforming catalyst exists in the catalyst layer 17 of this area or not will not become important. The catalyst filling area can be determined simply by the easiness of the filling operation of catalyst to the reforming catalyst layer and economic consideration on an filling of the unnecessary catalyst.
Thus, in this embodiment the reforming block holding a reforming catalyst is formed on one side of the reaction gas flow passage, and consequently, features are obtained as follows:
First, the cross section of the gas flow passage at reforming block is exactly the same (uniform) as the reaction gas flow passage before and after the reforming block, and the pressure drop through reforming block is minimized from the fact that the reforming catalyst is not held. In addition, no variation of the pressure drop resulting from the variation of filling of the reforming catalyst occurs, and the distribution of gas to the reforming block can be performed uniformly. Second, the gas flow passage structure and the catalyst filling structure can be separately designed and manufactured, the degree of freedom of the design is large, and therefore an easy structure can be obtained from the aspect of manufacturing. That is, in this embodiment, a plurality of hold spaces of reforming catalyst belonging to a plurality of reforming blocks can be collected into a single reforming catalyst layer 17, so a catalyst filling operation is considerably simplified. Because the disposition of the reforming blocks is prescribed by the setting of the permeable portion 16a of the partition plate 16, a complicated disposition of the reforming blocks, which is required in the aspect of the control of a reforming distribution, can be readily realized only by suitably setting the permeable portion of the partition plate. As a consequence, an ideal distribution of reforming reaction is obtainable with a compact reforming reactor.
Fourth Embodiment
As described above, in the reforming reactor where the gas flow passage including the reforming block is formed into a layer shape and the multilayer structure comprises this single lamination layer unit, the reforming block can be shared between a set of adjacent lamination layer units. The reforming reaction shown in FIG. 9 is a reactor of multilayer structure which comprises two reaction gas flow passages and a reforming catalyst layer 17 shared with both the reaction gas flow passages. A reforming block 13 is divided into small reforming blocks 13a, 13b, 13c, and 13d. Two adjacent reaction gas flow passages 12a and 12b are isolated from each other by the impermeable portion 16b of a partition plate 16. The partition plate 16 has permeable portions 16a so that the contact between the reforming catalyst 3 and the reaction gas in the gas flow passage is allowed at the positions of the reforming blocks 13a to 13d to advance a reforming reaction. That is, the partition plate 16 of this embodiment is impermeable at the area which separates the reaction gas flow passage from the space holding the catalyst, and is permeable at the area where the reforming blocks are set.
A sectional view where the disposition of the reforming blocks are viewed from the laminate layer side is shown in FIG. 9(b). In the figure, the reforming blocks and the final reforming block are indicated by oblique lines. The partition plate 16 in this embodiment is, for example, a porous plate which is bored by punching or etching only at the areas where the reforming blocks are positioned. As a structure of the reforming catalyst layer 17, there can be used a structure of a plate-shaped packed-bed type or a structure where a reforming catalyst is held on both surfaces of a corrugated plate such as that shown in FIG. 3 to form a plate-shaped hold space of catalyst. As a structure of the gas flow passages 12, a plurality of gas flow passages substantially divided from one another can be used. For instance, the upper and lower surfaces of a corrugated plate are interposed between the impermeable portions of the partition plate or between the housing plates of a reactor.
The embodiment, previously shown in FIG. 1, is constructed such that spaces for holding a reforming catalyst are independently provided in the reforming blocks. From the point of view that the temperatures of the reforming reactor are made uniform, it is preferable that the number of divisions of the reforming block are increased in the reforming chamber of the reforming reactor to obtain a smoother reforming distribution. On the other hand, if the number of the reforming blocks is increased, the manufacture of the reforming block will become complicated and the cost will become high. In the reforming reactor according to the embodiment shown in FIG. 9, the space for holding a reforming catalyst is a single space as a whole, and with respect to the setting of the reforming blocks, permeable portions provided in the partition plate, for example, aperture portions, can be provided so as to be aligned with the positions of the reforming blocks. For manufacture of a partition plate such as this, once a pattern for aperture portions is made, then the aperture portions can be easily mass-produced by punching or etching, and there is no problem about the complexity of disposition and manufacturing cost.
Thus, the embodiment shown in FIG. 9 has the advantage that the reforming reactor with the complicated disposition of reforming blocks can be cheaply and simply manufactured. In addition, the embodiment can provide a reforming reactor capable of favorable temperature control.
While the invention has been described with reference to specific embodiments thereof, it will be appreciated by those skilled in the art that numerous variations, modifications, and embodiments are possible, and accordingly, all such variations, modifications, and embodiments are to be regarded as being within the scope of the invention. | A reforming reactor includes a reforming chamber for reforming a reaction gas containing hydrocarbon or alcohol to a combustion gas containing hydrogen by a reforming reaction, a plurality of gas flow passages disposed in the reforming chamber for guiding the reaction gas from an inlet side toward an outlet side thereof, and reforming blocks provided in a plurality of predetermined sections of each of the gas flow passages and containing reforming catalysts with which the reaction gas flowing through the gas flow passages is brought into contact. | 8 |
BACKGROUND
[0001] The present invention relates to systems and methods used in downhole applications and, more particularly, to providing a seal in a casing annulus capable of stopping gas migration.
[0002] In the course of treating and preparing a subterranean well for production, downhole tools, such as well packers, are commonly run into the well on a conveyance such as a work string or production tubing. The purpose of the well packer is not only to support the production tubing and other completion equipment, such as sand control assemblies adjacent to a producing formation, but also to seal the annulus between the outside of the production tubing and the inside of the well casing or the well bore itself. As a result, the movement of fluids through the annulus and past the deployed location of the packer is substantially prevented.
[0003] Some well packers are designed to be set using complex electronics that often fail or may otherwise malfunction in the presence of corrosive and/or severe downhole environments. Other well packers require that the ambient conditions in the well be significantly altered in order to obtain adequate hydrostatic pressures to properly set the packer. While reliable in some applications, these and other methods of setting well packers add additional and unnecessary complexity and cost to the pack off process. Moreover, these conventional methods for setting the well packer are often only able to seal the annulus up to certain nominal pressures and thereafter are unable to prevent migration of fluids, such as gases, past the set well packer.
SUMMARY OF THE INVENTION
[0004] The present invention relates to systems and methods used in downhole applications and, more particularly, to providing a seal in a casing annulus capable of stopping gas migration.
[0005] In some embodiments, a system for sealing a wellbore annulus is disclosed. The system may include a base pipe having inner and outer radial surfaces and defining an elongate orifice, and an opening seat arranged against the inner radial surface and having a setting pin coupled thereto and extending radially through the elongate orifice, the setting pin being configured to axially translate in a first direction within the elongate orifice as the opening seat axially translates. The system may further include a piston arranged on the outer radial surface and being coupled to the setting pin such that axial translation of the opening seat correspondingly moves the piston, the piston having a piston biasing shoulder, and a lower shoe extending about the outer radial surface and having a mandrel biasing shoulder. The system may also include a packer disposed about the outer radial surface and interposing the piston and the lower shoe, the packer having a first packer element adjacent the piston and a second packer element adjacent the lower shoe, and a wellbore device disposed within the base pipe and configured to engage and move the opening seat, wherein as the opening seat axially translates in the first direction the first and second packer elements are compressed against the piston and mandrel biasing shoulders, respectively, and the first packer element forms a first seal in the annulus and the second packer element forms a second seal in the annulus, and wherein the first and second seals define a cavity therebetween that traps fluid therein and provides a hydraulic seal.
[0006] In some embodiments, a method for sealing a wellbore annulus is disclosed. The method may include engaging an opening seat with a wellbore device, the opening seat being movably arranged within a base pipe having inner and outer radial surfaces and defining an elongate orifice, the opening seat further having a setting pin coupled thereto and extending radially through the elongate orifice, and applying a predetermined axial force on the opening seat with the wellbore device and thereby axially moving the opening seat and the setting pin in a first direction. The method may further include moving in the first direction a piston arranged on the outer radial surface, the piston being coupled to the setting pin such that axial translation of the opening seat correspondingly moves the piston, wherein the piston has a piston biasing shoulder, and engaging and compressing a first packer element with the piston biasing shoulder and thereby forming a first seal within the wellbore annulus. The method may also include engaging and compressing a second packer element with a mandrel biasing shoulder and thereby forming a second seal within the wellbore annulus, and forming a hydraulic seal in a cavity defined between the first and second seals.
[0007] In some embodiments, a system for sealing a wellbore annulus may be disclosed. The system may include a base pipe having inner and outer radial surfaces and defining an elongate orifice, and an opening seat arranged against the inner radial surface and having a setting pin coupled thereto and extending radially through the elongate orifice, the setting pin being configured to axially translate in a first direction within the elongate orifice as the opening seat axially translates. The system may also include a piston arranged on the outer radial surface and being coupled to the setting pin such that axial translation of the opening seat correspondingly moves the piston, the piston having a piston biasing shoulder, a lower shoe extending about the outer radial surface and having a mandrel biasing shoulder, and a first ramped collar arranged about the base pipe and interposing the piston and the lower shoe, the first ramped collar having a first ramp and an opposing second ramp, and a first biasing shoulder and an opposing second biasing shoulder. The system may further include a first packer element disposed about the base pipe and arranged between the piston and the first ramped collar, a second packer element disposed about the base pipe and arranged between the lower shoe and the first ramped collar, and a wellbore device disposed within the base pipe and configured to engage and move the opening seat, wherein as the opening seat axially translates in the first direction the first and second packer elements are compressed and the first packer element forms a first seal in the annulus and the second packer element forms a second seal in the annulus.
[0008] In some embodiments, a system for sealing a wellbore annulus may be disclosed. The system may include a base pipe having inner and outer radial surfaces, a hydrostatic piston arranged within a hydrostatic chamber defined by a retainer element arranged about the base pipe, the retainer element having a retainer shoulder, and a compression sleeve arranged about the base pipe and coupled to the hydrostatic piston with a stem element extending from the hydrostatic piston, the compression sleeve having a sleeve shoulder. The system may also include first and second packer elements arranged about the base pipe and interposing the retainer element and the compression sleeve, and a wellbore device disposed within the base pipe and configured to engage and move an opening seat arranged against the inner radial surface, wherein moving the opening seat triggers a pressure differential across the hydrostatic piston and forces the hydrostatic piston to pull the compression sleeve into contact with the second packer element and the retainer element into contact with the first packer element, and wherein the first and second packer elements are compressed and form first and second seals, respectively, in the annulus and further define a cavity therebetween, the cavity being configured to trap fluid therein and provide a hydraulic seal.
[0009] The features and advantages of the present invention will be readily apparent to those skilled in the art upon a reading of the description of the preferred embodiments that follows.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] The following figures are included to illustrate certain aspects of the present invention, and should not be viewed as exclusive embodiments. The subject matter disclosed is capable of considerable modification, alteration, and equivalents in form and function, as will occur to those skilled in the art and having the benefit of this disclosure.
[0011] FIG. 1 illustrates a cross-sectional view of an exemplary downhole system, according to one or more embodiments disclosed.
[0012] FIG. 2 illustrates a cross-sectional view of the downhole system of FIG. 1 in an actuated configuration, according to one or more embodiments disclosed.
[0013] FIG. 3 illustrates a cross-sectional view of another exemplary downhole system, according to one or more embodiments disclosed.
[0014] FIG. 4 illustrates a cross-sectional view of another exemplary downhole system, according to one or more embodiments disclosed.
[0015] FIG. 5 illustrates a cross-sectional view of another exemplary downhole system, according to one or more embodiments disclosed.
[0016] FIG. 6 illustrates a cross-sectional view of another exemplary downhole system, according to one or more embodiments disclosed.
[0017] FIG. 7 illustrates a cross-sectional view of another exemplary downhole system, according to one or more embodiments disclosed.
[0018] FIG. 8 illustrates a cross-sectional view of another exemplary downhole system, according to one or more embodiments disclosed.
DETAILED DESCRIPTION
[0019] The present invention relates to systems and methods used in downhole applications and, more particularly, to providing a seal in a casing annulus capable of stopping gas migration.
[0020] As will be discussed in detail below, several advantages are gained through the systems and methods disclosed herein. For example, the disclosed systems and methods initiate and set a downhole tool, such as one or more well packers or packer elements, in order to isolate the annular space defined between a completion casing and a base pipe (e.g., production string). The set packer is able to create a seal that prevents the migration of fluids through the annulus, thereby isolating the areas above and below. The packer may be set using hydraulic and/or mechanical means, and adjacent packer elements may provide one or more hydraulic seals in the annulus that prevent or otherwise eliminate the migration of gases at elevated pressures. To facilitate a better understanding of the present invention, the following examples are given. It should be noted that the examples provided are not to be read as limiting or defining the scope of the invention.
[0021] Referring to FIG. 1 , illustrated is a cross-sectional view of an exemplary downhole system 100 configured to seal a wellbore annulus, according to one or more embodiments. The system 100 may include a base pipe 102 extending within a casing 104 that has been cemented in a wellbore (not shown) drilled into the Earth's surface in order to penetrate various earth strata containing hydrocarbon formations. The system 100 is not limited to any specific type of well, but rather may be used in all types, such as vertical wells, horizontal wells, multilateral (e.g., slanted) wells, combinations thereof, and the like. An annulus 106 may be defined between the casing 104 and the base pipe 102 . The casing 104 forms a protective lining within the wellbore and may be made from materials such as metals, plastics, composites, or the like. In at least one embodiment, the casing 104 may be omitted and the annulus 106 may instead be defined between the inner wall of the wellbore itself and the base pipe 102 .
[0022] The base pipe 102 may be coupled to or form part of production tubing. In some embodiments, the base pipe 102 may include one or more tubular joints, having metal-to-metal threaded connections or otherwise threadedly joined to form a tubing string. In other embodiments, the base pipe 102 may form a portion of a coiled tubing. The base pipe 102 may have a generally tubular shape, with an inner radial surface 102 a and an outer radial surface 102 b having substantially concentric and circular cross-sections. However, other configurations may be suitable, depending on particular conditions and circumstances. For example, some configurations of the base pipe 102 may include offset bores, sidepockets, etc. The base pipe 102 may include portions formed of a non-uniform construction, for example, a joint of tubing having compartments, cavities or other components therein or thereon. In some embodiments, at least a portion of the base pipe 102 may be profiled or otherwise characterized as a mandrel-type device or structure.
[0023] As illustrated, the system 100 may include at least one packer 108 disposed about the base pipe 102 . The packer 108 may be disposed about the base pipe 102 in a number of ways. For example, in some embodiments the packer 108 may directly or indirectly contact the outer radial surface 102 b of the base pipe 102 . In other embodiments, however, the packer 108 may be arranged about or otherwise radially-offset from another component of the base pipe 102 . The packer 108 may include a first packer element 108 a and a second packer element 108 b, having a spacer 108 c interposing the first and second packer elements 108 a,b. As will be described in more detail below, the packer 108 may be configured to be compressed radially outward when subjected to axial compressive forces, thereby sealing the annulus in one or more locations.
[0024] The system 100 may further include an upper shoe 110 a and a lower shoe 110 b coupled to and extending about the base pipe 102 . The upper and lower shoes 110 a,b may be configured to axially bound the various components of the system 100 arranged about the outer surface 102 b of the base pipe 102 . In one or more embodiments, the lower shoe 110 b may form an integral part of the base pipe 102 , such that it serves as a mandrel-type device that helps compress the packer 108 during operation. In other embodiments, as illustrated, the lower shoe 110 b may bias against a shoulder 112 defined on the base pipe 102 , such that the lower shoe 110 b is substantially prevented from moving axially to the right, as indicated by arrow A.
[0025] The system 100 may further include a shear ring 114 , a lock ring housing 116 , a guide sleeve 118 , and a piston 120 . The shear ring 114 may be arranged axially adjacent the upper shoe 110 a and adapted to house one or more shear pins 122 . The shear pins 122 may extend partially into the base pipe 102 in order to maintain the components of the system 100 arranged about the outer radial surface 102 b in their axial placement until properly actuated. In some embodiments, eight shear pins 122 are employed and spaced about the outer radial surface 102 b of the base pipe 102 . As will be appreciated, however, more or less than eight shear pins 122 may be employed, without departing from the scope of the disclosure.
[0026] The lock ring housing 116 may be arranged axially adjacent the shear ring 114 and may house a lock ring 124 therein. In some embodiments, the lock ring housing 116 may be threaded onto the shear ring 114 and therefore able to move axially therewith. The lock ring 124 may be coupled or otherwise secured to the lock ring housing 116 using one or more lock pins 126 . In other embodiments, however, the lock ring housing 116 may be threaded onto the lock ring 124 , without departing from the scope of the disclosure.
[0027] In one or more embodiments, the lock ring 124 may define a plurality of ramped locking teeth 128 . In operation, the lock ring 124 may be configured to slidingly engage the outer surface 102 b of the base pipe 102 as the system 100 moves axially in the direction A. As the lock ring 124 translates axially, the ramped locking teeth 128 may be configured to engage corresponding teeth or grooves (not shown) defined on the outer surface 102 b of the base pipe 102 , thereby locking the lock ring 124 in its advanced axial position and generally preventing the system 100 from returning in the opposing axial direction.
[0028] The guide sleeve 118 may be arranged axially adjacent the lock ring housing 116 and configured to interpose or otherwise connect the lock ring housing 116 to the piston 120 . In some embodiments, the guide sleeve 118 may be threaded onto both the lock ring housing 116 and the piston 120 . One or more sealing components 132 may be configured to seal the radial engagement between the piston 120 and the guide sleeve 118 . In some embodiments, the sealing components 132 may be o-rings. In other embodiments, the sealing components 132 may be other types of seals known to those skilled in the art.
[0029] The piston 120 may include a piston biasing shoulder 134 a and a piston ramp 136 a. The piston ramp 136 a may be arranged axially adjacent the first packer element 108 a and configured to slidingly engage the first packer element 108 a as the packer 108 is being set. Likewise, the lower shoe 110 b may define a mandrel biasing shoulder 134 b and a mandrel ramp 136 b arranged axially adjacent the second packer element 108 b. The mandrel ramp 136 b may be configured to slidingly engage the second packer element 108 b as the packer 108 is being set.
[0030] The system 100 may further include an opening seat 138 axially movable and arranged within the base pipe 102 . The opening seat 138 may be disposed against the inner radial surface 102 a of the base pipe 102 and secured in its axial position therein using one or more setting pins 140 . Although only one setting pin 140 is shown in FIG. 1 , it will be appreciated that any number of setting pins 140 may be used without departing from the scope of the disclosure. In at least one embodiment, five setting pins 140 may be employed in order to secure the opening seat 138 in its axial position within the base pipe 102 .
[0031] The setting pins 140 may be spaced circumferentially about the inner radial surface 102 a of the base pipe 102 . The setting pins 140 may extend through an axially elongate orifice 144 defined in the base pipe 102 in order to structurally couple the opening seat 138 to the piston 120 . For example, the setting pins 140 may extend between corresponding holes 142 defined in the piston 120 and corresponding holes 130 defined in the opening seat 138 . In some embodiments, the setting pins 140 are threaded into the holes 142 , 130 . In other embodiments, however, the setting pins 140 are attached to the piston 120 and/or the opening seat 138 by welding, brazing, adhesives, combinations thereof, or other attachment means.
[0032] In response to an axial force applied to the opening seat 138 in the direction A, the setting pins 140 may be correspondingly forced to translate axially within the elongate orifice 144 , thereby also forcing the piston 120 to translate in the direction A. However, as a result of the connective combination of the piston 120 , the guide sleeve 118 , the lock ring, 116 , and the shear ring 114 , the setting pins 140 are prevented from axially translating while the one or more shear pins 122 are intact or otherwise engaged with the base pipe 102 .
[0033] Referring now to FIG. 2 , illustrated is the exemplary downhole system 100 in a compressed configuration or otherwise where the packer 108 has been properly set, according to one or more embodiments. In exemplary operation of the system 100 , a wellbore device 202 may be introduced into the well, within the base pipe 102 , and configured to engage and move the opening seat 138 in the direction A. In at least one embodiment, the wellbore device 202 is a plug, as known by those skilled in the art. In other embodiments, however, the wellbore device 202 may be another type of downhole device such as, but not limited to, a ball or a dart. In some embodiments, the wellbore device 202 may be configured to engage a profiled portion 203 defined on an upper end of the opening seat 138 . In other embodiments, however, the wellbore device 202 may be configured to engage any portion of the opening seat 138 , without departing from the scope of the disclosure.
[0034] Once the wellbore device 202 engages the opening seat 138 , a predetermined axial force in the direction A may be applied to the upper end of the wellbore device 202 in order to convey a corresponding axial force to the opening seat 138 and the one or more setting pins 140 coupled thereto. In some embodiments, the predetermined axial force may be applied to the wellbore device 202 by increasing fluid pressure within the base pipe 102 . For instance, the wellbore device 202 may be adapted to sealingly engage the opening seat 138 or otherwise substantially seal against the inner radial surface 102 a of the base pipe 102 such that a fluid pumped from the surface hydraulically forces the wellbore device 202 against the opening seat 138 . Increasing the fluid pressure within the base pipe 102 correspondingly increases the axial force applied by the wellbore device 202 on the opening seat 138 , and therefore increases the axial force applied to piston 120 via the setting pins 140 . Further increasing the fluid pressure within the base pipe 102 may serve to shear the shear pin(s) 122 and thereby allow the opening seat 138 and piston 120 to axially translate in the direction A.
[0035] In one or more embodiments, the predetermined axial force required to shear the shear pins 122 and thereby move the opening seat 138 and setting pins 140 in the direction A may be about 500 psi. In other embodiments, however, the predetermined axial force may be more or less than 500 psi, without departing from the scope of the disclosure. As will be appreciated, in other embodiments the predetermined axial force may be applied to the opening seat 138 in other ways, such as a mechanical force applied to the wellbore device 202 which transfers its force to the opening seat 138 .
[0036] As the opening seat 138 translates axially in the direction A, and the setting pins 140 translate within the elongate orifice 144 , the piston 120 is correspondingly forced to translate axially and into increased contact and interaction with the packer 108 . In particular, the first packer element 108 a may slidably engage and ride up the piston ramp 136 a until coming into contact with the piston biasing shoulder 134 a. Likewise, the second packer element 108 b may slidably engage and ride up the mandrel ramp 136 b until coming into contact with the mandrel biasing shoulder 134 b. Upon engaging the respective biasing shoulders 134 a,b, and with continued axial movement in direction A, the first and second packer elements 108 a,b may be compressed and extend radially to engage the inner wall of the casing 104 . In one or more embodiments, the system 100 is prevented from reversing direction, and thereby decreasing the radial compression of the packer 108 , by the ramped locking teeth 128 that engage corresponding teeth or grooves (not shown) defined on the outer surface 102 b of the base pipe 102 . It will be appreciated, however, that other means of securing the system 100 in its compressed configuration may be used, without departing from the scope of the disclosure.
[0037] Accordingly, compressing the packer 108 between the piston 120 and the lower shoe 110 b serves to effectively isolate or otherwise seal portions of the annulus 106 above and below the packer 108 . As illustrated, the packer 108 may be configured to form a first seal 204 within the annulus 106 where the first packer element 108 a seals against the inner wall of the casing 104 . Likewise, a second seal 206 may be formed in the annulus 106 where the second packer element 108 b seals against the inner wall of the casing 104 . In operation, the first and second seals 204 , 206 may be configured to substantially prevent fluid migration between the upper and lower portions of the annulus 106 .
[0038] As the first and second seals 204 , 206 are generated, a cavity 208 may be formed between the compressed first and second packer elements 108 a,b and extending axially across the spacer 108 c. The first and second packer elements 108 a,b trap fluid within the cavity 208 and as the elements 108 a,b are further compressed axially, the elastomeric material of each element 108 a,b may compress the cavity 208 and thereby increase the fluid pressure therein. Accordingly, a third seal 210 may be generated within the cavity 208 and characterized as a hydraulic seal.
[0039] In at least one embodiment, a predetermined axial force of about 500 psi, as applied to the wellbore device 202 and correspondingly transferred to the piston 120 through the interconnection with the opening seat 138 , may result in a fluid pressure generated in the cavity 208 of about 10,000 psi or more. In other embodiments, pressures greater or less than 10,000 psi may be obtained within the cavity 208 , without departing from the scope of the disclosure. The increased pressures of the hydraulic third seal 210 may help the packer 108 prevent or otherwise entirely eliminate the migration of fluids (e.g., gases) through the packer 108 .
[0040] Referring now to FIG. 3 , illustrated is another exemplary downhole system 300 configured to seal a wellbore annulus, according to one or more embodiments. The downhole system 300 may be similar in several respects to the downhole system 100 described above with reference to FIGS. 1 and 2 , and therefore may be best understood with reference thereto, where like numerals indicate like components that will not be described again in detail. As illustrated, the system 300 may include a ramped collar 302 slidably arranged about the base pipe 102 and interposing the first and second packer elements 108 a,b. The ramped collar may include one or more sealing components 303 configured to seal the sliding engagement between the ramped collar 302 and the base pipe 102 . In some embodiments, the sealing components 303 may be o-rings. In other embodiments, however, the sealing components 303 may be other types of seals known to those skilled in the art.
[0041] The ramped collar 302 may further include a first ramp 304 a and an opposing second ramp 304 b, and a first biasing shoulder 306 a and an opposing second biasing shoulder 306 b. The piston 120 may define or otherwise provide a square piston shoulder 308 a juxtaposed against the first packer element 108 a. Likewise, the lower shoe 110 b may define or otherwise provide a square mandrel shoulder 308 b juxtaposed against the second packer element 108 b. Axial translation of the piston 120 in the direction A in FIG. 3 , as well as in one or more of the embodiments discussed below, may be realized in a manner substantially similar to the axial translation of the piston 120 as discussed above with reference to FIGS. 1 and 2 , and therefore will not be discussed again in detail.
[0042] The first ramp 304 a may be arranged axially adjacent the first packer element 108 a and configured to slidably engage the first packer element 108 a as the square piston shoulder 308 a pushes the first packer element 108 a axially in the direction A. Likewise, the second ramp 304 b may be arranged axially adjacent the second packer element 108 b and configured to slidably engage the second packer element 108 b as the ramped collar 302 translates axially in the direction A and the square mandrel shoulder 308 b prevents the second packer element 108 b from moving in direction A.
[0043] Further axial movement of the piston 120 in direction A forces the first and second packer elements 108 a,b into engagement with the first and second biasing shoulders 306 a,b, respectively. Upon engaging the respective biasing shoulders 306 a,b, and with continued axial movement in direction A, the first and second packer elements 108 a,b are compressed and extend radially to engage the inner wall of the casing 104 . As a result, the first packer element 108 a may be configured to form a first seal 310 where the first packer element 108 a engages the inner wall of the casing 104 , and the second packer element 108 b may form a second seal 312 where the second packer element 108 b engages the inner wall of the casing 104 .
[0044] As the first and second seals 310 , 312 are generated, a cavity 314 may be formed between the first and second packer elements 108 a,b and extending axially across a portion of the ramped collar 302 . The first and second packer elements 108 a,b trap fluid within the cavity 314 and as the elements 108 a,b are further compressed axially, the elastomeric material of each element 108 a,b may compress the cavity 314 and thereby increase the fluid pressure therein. Accordingly, a third seal 316 may be generated within the cavity 314 and characterized as a hydraulic seal, similar to the third seal 210 described above with reference to FIG. 2 . It should be noted that the seals 310 , 312 , and 316 shown in
[0045] FIG. 3 are not depicted as compressed against the casing 104 as described above, but instead their general location is indicated.
[0046] Referring now to FIG. 4 , illustrated is another exemplary downhole system 400 configured to seal a wellbore annulus, according to one or more embodiments. The downhole system 400 may be similar in several respects to the downhole systems 100 and 300 described above with reference thereto, and therefore may be best understood with reference to FIGS. 1-3 , where like numerals indicate like components that will not be described again in detail. As illustrated, the system 400 includes the ramped collar 302 interposing the packer 108 and a third packer element 402 . Specifically, the first ramp 304 a may be arranged axially adjacent the third packer element 402 and configured to slidably engage the third packer element 402 as it is pushed axially in direction A by the square piston shoulder 308 a. The second ramp 304 b may be arranged axially adjacent the first packer element 108 a and configured to slidably engage the first packer element 108 a as the ramped collar 302 translates axially in the direction A. The mandrel ramp 136 b of the lower shoe 110 b may be arranged axially adjacent the second packer element 108 b and configured to slidingly engage the second packer element 108 b as the packer 108 is being set.
[0047] Further axial movement of the piston 120 in direction A forces the third packer element 402 into engagement with the first biasing shoulder 306 a, the first packer element 108 a into engagement with the second biasing shoulder 306 b, and the second packer element 108 b into engagement with the mandrel biasing shoulder 134 b. Upon engaging the respective shoulders 306 a,b, 134 b, and with continued axial force in direction A, the third, first, and second packer elements 402 , 108 a,b are compressed and extend radially to engage the inner wall of the casing 104 . As a result, the first, second, and third packer elements 108 a,b, 402 form first, second, and third seals 404 , 406 , 408 , respectively, at the location where each engages the inner wall of the casing 104 .
[0048] Moreover, as the first, second, and third seals 404 , 406 , 408 are generated, a first cavity 410 may be formed between the first and second packer elements 108 a,b and extending axially across the spacer 108 c, and a second cavity 412 may be formed between the first and third packer elements 108 a, 402 and extending axially across a portion of the ramped collar 302 . The compressed packer elements 108 a,b, 402 trap fluid within the respectively formed cavities 410 , 412 and as the packer elements 108 a,b, 402 are further compressed axially, the fluid pressure in each cavity 410 , 412 increases to provide a hydraulic third seal 414 and a hydraulic fourth seal 416 , similar to the third seal 210 described above with reference to FIG. 2 . It should be noted that the seals 404 , 406 , 408 , 414 , and 416 shown in FIG. 4 are not depicted as compressed against the casing 104 as described above, but instead their general location is indicated.
[0049] Referring now to FIG. 5 , illustrated is another exemplary downhole system 500 configured to seal a wellbore annulus, according to one or more embodiments. The downhole system 500 may be similar in several respects to the downhole systems 100 and 300 described above with reference to FIGS. 1-3 , and therefore may be best understood with reference thereto, where like numerals indicate like components that will not be described again in detail. As illustrated, the system 500 includes a first packer 502 and a second packer 504 axially spaced from each other and disposed about the base pipe 102 . The first packer 502 may include a first packer element 502 a and a second packer element 502 b, having a spacer 502 c interposing the first and second packer elements 502 a,b. The second packer 504 may include a third packer element 504 a and a fourth packer element 504 b, having a spacer 504 c interposing the third and fourth packer elements 504 a,b.
[0050] The system 500 may further include the ramped collar 302 arranged between the first and second packers 502 , 504 . Specifically, the first ramp 304 a may be arranged axially adjacent and slidably engaging the second packer element 502 b and the second ramp 304 b may be arranged axially adjacent and slidably engaging the third packer element 504 a. Moreover, the first packer element 502 a may be arranged axially adjacent and slidably engaging the piston ramp 136 a and the fourth packer element 504 b may be arranged axially adjacent and slidably engaging the mandrel ramp 136 b. As the piston 120 translates axially in the direction A, the first packer element 502 a eventually engages the piston biasing shoulder 134 a, which forces the second packer element 502 b into contact with the first biasing shoulder 306 a and thereby moves the ramped collar 302 . Axial movement of the ramped collar 302 in the direction A allows the third packer element 504 a to contact the second biasing shoulder 306 b and the fourth packer element 504 b to contact the mandrel biasing shoulder 134 b.
[0051] Upon engaging the respective shoulders 134 a,b, 306 a,b, and with continued axial force in direction A, the first, second, third and fourth packer elements 502 a,b, 504 a,b, are compressed and extend radially to engage the inner wall of the casing 104 . As a result, the first, second, third and fourth packer elements 502 a,b, 504 a,b form first, second, third, and fourth seals 506 , 508 , 510 , 512 , respectively, at the location where each engages the inner wall of the casing 104 .
[0052] As the first, second, third, and fourth seals 506 , 508 , 510 , 512 are generated, a first cavity 514 may be formed between the first and second packer elements 502 a,b and extending axially across the spacer 502 c, a second cavity 516 may be formed between the third and fourth packer elements 504 a,b and extending axially across the spacer 504 c, and a third cavity 518 may be formed between the second and third packer elements 502 b, 504 and extending axially across a portion of the ramped collar 302 . Increased compression of the first, second, third, and fourth packer elements 502 a,b, 504 a,b increases the fluid pressure within the first, second, and third cavities 514 , 516 , 518 , thereby forming fifth, sixth, and seventh seals 520 , 522 , 524 , respectively, each characterized as hydraulic seals similar to the third seal 210 described above with reference to FIG. 2 . It should be noted that the seals 506 , 508 , 510 , 512 , 520 , 522 , and 524 shown in FIG. 5 are not depicted as compressed against the casing 104 as described above, but instead their general location is indicated.
[0053] Referring now to FIG. 6 , illustrated is another exemplary downhole system 600 configured to seal a wellbore annulus, according to one or more embodiments. The downhole system 600 may be similar in several respects to the downhole systems 100 and 300 described above with reference to FIGS. 1-3 , and therefore may be best understood with reference thereto, where like numerals indicate like components that will not be described again in detail. As illustrated, the system 600 includes a first ramped collar 602 and a second ramped collar 604 slidably arranged about the base pipe 102 . The first and second ramped collars 602 , 604 may be similar to the ramped collar 302 described above with reference to FIG. 3 . Specifically, the first ramped collar 602 may include a first ramp 606 a and an opposing second ramp 606 b, and a first biasing shoulder 608 a and an opposing second biasing shoulder 608 b. Moreover, the second ramped collar 604 may include a third ramp 610 a and an opposing fourth ramp 610 b, and a third biasing shoulder 612 a and an opposing fourth biasing shoulder 612 b.
[0054] A packer 614 having a first packer element 614 a and a second packer element 614 b may interpose the first and second ramped collars 602 , 604 such that the first packer element 614 a slidably engages the second ramp 606 b and the second packer element 614 b slidably engages the third ramp 610 a. As illustrated, the system 600 may further include a third packer element 616 and a fourth packer element 618 axially spaced from the packer 614 and arranged about the base pipe 102 . The third packer element 616 may be configured to slidably engage the first ramp 606 a and bias the square piston shoulder 308 a, and the fourth packer element 618 may be configured to slidably engage the fourth ramp 610 b and bias the square mandrel shoulder 308 b.
[0055] As the piston 120 translates axially in the direction A, the square piston shoulder 308 a forces the third packer element 616 into engagement with the first biasing shoulder 608 a, which forces the first ramped collar 602 to likewise translate axially such that the first packer element 614 a comes into contact with the second biasing shoulder 608 b. Further axial movement of the first ramped collar 602 forces the packer 614 to translate axially until the second packer element 614 b engages the third biasing shoulder 612 a, which forces the second ramped collar 604 to translate axially such that the fourth packer element 618 comes into contact with the fourth biasing shoulder 612 b as it is biased on its opposite end by the immovable square mandrel shoulder 308 b. Upon engaging the respective shoulders 308 a,b, 608 a,b, and 612 a,b, and with continued axial force in direction A, the first, second, third, and fourth packer elements 614 a,b, 616 , 618 are compressed and extend radially to engage the inner wall of the casing 104 . As a result, the first, second, third, and fourth packer elements 614 a,b, 616 , 618 form first, second, third, and fourth seals 620 , 622 , 624 , 626 , respectively, at the location where each engages the inner wall of the casing 104 .
[0056] As the first, second, third, and fourth seals 620 , 622 , 624 , 626 are generated, a first cavity 628 may be formed between the first and second packer elements 614 a,b and extend axially across the spacer 614 c, a second cavity 630 may be formed between the third and first packer elements 616 , 614 a and extend axially across a portion of the first ramped collar 602 , and a third cavity 632 may be formed between the second and fourth packer elements 614 b, 618 and extend axially across a portion of the second ramped collar 604 . Increased compression of the first, second, third, and fourth packer elements 614 a,b, 616 , 618 increases the fluid pressure within the first, second, and third cavities 628 , 630 , 632 , thereby forming fifth, sixth, and seventh seals 634 , 636 , 638 , respectively, each characterized as hydraulic seals similar to the third seal 210 described above with reference to FIG. 2 . It should be noted that the seals 620 , 622 , 624 , 626 , 634 , 636 , and 638 shown in FIG. 6 are not depicted as compressed against the casing 104 as described above, but instead their general location is indicated.
[0057] Referring now to FIG. 7 , illustrated is another exemplary downhole system 700 configured to seal a wellbore annulus, according to one or more embodiments. The downhole system 700 may be similar in several respects to the downhole systems 100 and 300 described above with reference to FIGS. 1-3 , and therefore may be best understood with reference thereto, where like numerals indicate like components that will not be described again in detail. As illustrated, the system 700 includes the ramped collar 302 interposing a first packer element 702 and a second packer element 704 such that the first ramp 304 a slidably engages the first packer element 702 and the second ramp 304 b slidably engages the second packer element 704 .
[0058] The system 700 may further include a shoulder ramp 706 interposing the second packer element 704 and a third packer element 708 . The shoulder ramp 706 may be axially offset from the ramp collar 302 and disposed about the base pipe 102 . Moreover, the shoulder ramp 706 may include a square shoulder 710 , an opposing biasing shoulder 712 , and a third ramp 714 , where the square shoulder 710 biases the second packer element 704 and the third ramp 714 slidably engages the third packer element 708 .
[0059] As the piston 120 translates axially in direction A, the square piston shoulder 308 a forces the first packer element 702 into engagement with the first biasing shoulder 306 a, which forces the ramped collar 302 to likewise translate axially such that the second packer element 704 comes into contact with the second biasing shoulder 306 b. Further axial movement of the ramped collar 302 , in conjunction with the immovable square mandrel shoulder 308 b, forces the shoulder ramp 706 to likewise translate axially until the third packer element 708 comes into contact with the biasing shoulder 712 of the shoulder ramp 706 . Upon engaging the respective shoulders 308 a,b, 306 a,b, 710 , and 712 , and with continued axial force in direction A, the first, second, and third packer elements 702 , 704 , 708 are compressed and extend radially to engage the inner wall of the casing 104 . As a result, the first, second, and third packer elements 702 , 704 , 708 form first, second, and third seals 715 , 716 , 718 , respectively, at the location where each engages the inner wall of the casing 104 .
[0060] As the first, second, and third seals 715 , 716 , 718 are generated, a first cavity 720 may be formed between the first and second packer elements 702 , 704 and extend axially across a portion of the ramped collar 302 , and a second cavity 722 may be formed between the second and third packer elements 704 , 708 and extend axially across a portion of the shoulder ramp 706 . Increased compression of the first, second, and third packer elements 702 , 704 , 708 increases the fluid pressure within the first and second cavities 720 , 722 , thereby forming fourth and fifth seals 724 , 726 , respectively, each characterized as hydraulic seals similar to the third seal 210 described above with reference to FIG. 2 . It should be noted that the seals 715 , 716 , 718 , 724 , and 726 shown in FIG. 7 are not depicted as compressed against the casing 104 as described above, but instead their general location is indicated.
[0061] Referring now to FIG. 8 , illustrated is another exemplary downhole system 800 configured to seal a wellbore annulus, according to one or more embodiments. The downhole system 800 may be similar in several respects to the downhole systems 100 and 300 described above with reference to FIGS. 1-3 , and therefore may be best understood with reference thereto, where like numerals indicate like components that will not be described again in detail. The downhole system 800 may be configured to compress the packer 108 and seal the annulus 106 using hydrostatic pressure. As illustrated, the system 800 may include a hydrostatic piston 804 housed within a hydrostatic chamber 806 . The hydrostatic chamber 806 may be at least partially defined by a retainer element 808 arranged about the base pipe 102 . One or more inlet ports 810 may be defined in the retainer element 808 and thereby provide fluid communication between the annulus 106 and the hydrostatic chamber 806 .
[0062] The piston 804 may include a stem portion 804 a that extends axially from the piston 804 and interposes the packer 108 and the base pipe 102 . The stem portion 804 a may be coupled to compression sleeve 812 having a sleeve ramp 814 and a sleeve shoulder 816 . The hydrostatic chamber 806 may contain fluid under hydrostatic pressure from the annulus 106 , and the hydrostatic piston 804 remains in fluid equilibrium until a pressure differential is experienced across the hydrostatic piston 804 , at which point the piston 804 translates axially in a direction B within the hydrostatic chamber 806 as it seeks pressure equilibrium once again.
[0063] As the hydrostatic piston 804 translates in direction B, the compression sleeve 812 coupled to the stem portion 804 a is forced toward the second packer element 108 b and the second packer element 108 b rides up the sleeve ramp 814 and biases the sleeve shoulder 816 . Likewise, the first packer element 108 a may ride up a retainer ramp 818 and bias a retainer shoulder 820 , each being defined on the retainer element 808 . As a result the packer is compressed radially and seals against the inner wall of the casing 104 .
[0064] The hydrostatic piston 804 may be actuated by introducing the wellbore device 202 ( FIG. 2 ) into the base pipe 102 and moving the opening seat 138 in the direction A, as generally described above. Moving the opening seat 138 in direction A may trigger high pressure formation or wellbore fluids from the annulus 106 to enter the hydrostatic chamber 806 via the one or more inlet ports 810 defined in the retainer element 808 . As the hydrostatic piston 804 attempts to regain hydrostatic equilibrium, it will move axially in direction B, thereby compressing the packer 108 to form a first seal 821 within the annulus 106 where the first packer element 108 a seals against the inner wall of the casing 104 . Likewise, a second seal 822 may be formed in the annulus 106 where the second packer element 108 b seals against the inner wall of the casing 104 .
[0065] As the first and second seals 821 , 822 are generated, a cavity 824 may be formed between the compressed first and second packer elements 108 a,b and extending axially across the spacer 108 c. Increased compression of the first and second packer elements 108 a,b increases the fluid pressure within the cavity 824 , thereby forming a third seal 826 , characterized as a hydraulic seal similar to the third seal 210 described above with reference to FIG. 2 . It should be noted that the seals 821 , 822 , and 826 shown in FIG. 8 are not depicted as compressed against the casing 104 as described above, but instead their general location is indicated.
[0066] It will be appreciated that the various components of each system 100 , 300 - 800 may be mixed, duplicated, rearranged, combined with components of other systems 100 , 300 - 800 , or otherwise altered in various axial configurations in order to fit particular wellbore applications. Accordingly, the disclosed systems 100 , 300 - 800 and related methods may be used to remotely set one or more packers or packer elements. Setting the packer elements not only provides corresponding seals against the inner wall of the wellbore, but also creates hydraulic seals between adjacent packer elements. Because these hydraulic seals pressurize a trapped fluid, they exhibit an increased pressure threshold and therefore an enhanced ability to prevent the migration of fluids therethrough. Consequently, the annulus 106 is better sealed on either side of each hydraulic seal.
[0067] A method for sealing a wellbore annulus is also disclosed herein. In some embodiments, the method may include engaging an opening seat with a wellbore device. The opening seat may be movably arranged within a base pipe having inner and outer radial surfaces and defining an elongate orifice. The opening seat may further include a setting pin coupled thereto and extending radially through the elongate orifice. The method may also include applying a predetermined axial force on the opening seat with the wellbore device and thereby axially moving the opening seat and the setting pin in a first direction, and moving in the first direction a piston arranged on the outer radial surface. The piston may be coupled to the setting pin such that axial translation of the opening seat correspondingly moves the piston. The piston may also define or otherwise provide a piston biasing shoulder. The method may further include engaging and compressing a first packer element with the piston biasing shoulder and thereby forming a first seal within the wellbore annulus, and engaging and compressing a second packer element with a mandrel biasing shoulder and thereby forming a second seal within the wellbore annulus. The method may further include forming a hydraulic seal in a cavity defined between the first and second seals.
[0068] In some embodiments, applying the predetermined axial force on the opening seat may include applying fluid pressure against the wellbore device. In some embodiments, the method may further include shearing one or more shear pins that secure the piston against axial translation in the first direction. The method may also include slidingly engaging the first packer element with a piston ramp defined by the piston, and slidingly engaging the second packer element with a mandrel ramp. In one or more embodiments, the method also includes engaging and further compressing the first packer element with a first shoulder defined on a ramped collar arranged about the base pipe and interposing the first and second packer elements, and further engaging and further compressing the second packer element with a second shoulder defined on the ramped collar. Axial movement of the piston in the first direction forces the first and second packer elements into engagement with the first and second biasing shoulders, respectively. In some embodiments, forming a hydraulic seal in the cavity further comprises pressurizing the cavity to a pressure of about 10,000 psi or more.
[0069] In some aspects, a system for sealing a wellbore annulus defined between a base pipe and a casing is disclosed. The system may include a piston arranged on an outer radial surface of the base pipe, the piston having a piston ramp and a piston biasing shoulder, a lower shoe extending about the outer radial surface and having a mandrel ramp and a mandrel biasing shoulder, and a packer disposed about the base pipe and interposing the piston and the lower shoe, the packer having a first packer element adjacent the piston and a second packer element adjacent the lower shoe, wherein as the piston axially translates the first and second packer elements are compressed against the piston and mandrel biasing shoulders, respectively, and the first packer element forms a first seal against the casing in the annulus and the second packer element forms a second seal against the casing in the annulus, and wherein the first and second seals define a cavity therebetween that traps fluid within the cavity and thereby provides a hydraulic seal.
[0070] In some aspects a method for sealing a wellbore annulus defined between a base pipe and a casing is disclosed. The method may include axially translating a piston arranged on an outer radial surface of a base pipe, the piston having a piston biasing shoulder, engaging and compressing a first packer element with the piston biasing shoulder and thereby forming a first seal against the casing within the wellbore annulus, engaging and compressing a second packer element with a mandrel biasing shoulder and thereby forming a second seal against the casing within the wellbore annulus, and forming a hydraulic seal in a cavity defined between the first and second seals.
[0071] In some aspects, a system for sealing a wellbore annulus defined between a base pipe and a casing is disclosed. The system may include a piston arranged on an outer radial surface of the base pipe, the piston having a piston biasing shoulder, a lower shoe extending about the outer radial surface and having a mandrel biasing shoulder, a first ramped collar arranged about the base pipe and interposing the piston and the lower shoe, the first ramped collar having a first ramp and an opposing second ramp, and a first biasing shoulder and an opposing second biasing shoulder, a first packer element disposed about the base pipe and arranged between the piston and the first ramped collar, and a second packer element disposed about the base pipe and arranged between the lower shoe and the first ramped collar, wherein as the piston axially translates the first and second packer elements are compressed against the piston and mandrel biasing shoulders, respectively, and the first packer element forms a first seal against the casing in the annulus and the second packer element forms a second seal against the casing in the annulus, and wherein the first and second seals define a cavity therebetween that traps fluid within the cavity and thereby provides a hydraulic seal.
[0072] In some aspects, a system for sealing a wellbore annulus defined between a base pipe and a casing is disclosed. The system may include a retainer element arranged about a base pipe and defining a hydrostatic chamber that houses a hydrostatic piston having a stem portion that extends axially, the retainer element having a retainer ramp and a retainer shoulder, a compression sleeve arranged about the base pipe and coupled to the hydrostatic piston via the stem element, the compression sleeve having a sleeve ramp and a sleeve shoulder, and first and second packer elements arranged about the base pipe and interposing the retainer element and the compression sleeve, the first packer element being adjacent the retainer element and the second packer element being adjacent the compression sleeve, wherein as the hydrostatic piston axially translates, it pulls the compression sleeve into contact with the second packer element and the retainer element into contact with the first packer element, and wherein the first and second packer elements are compressed and form first and second seals against the casing, respectively, in the annulus and further define a cavity therebetween, the cavity being configured to trap fluid therein and provide a hydraulic seal.
[0073] In the following description of the representative embodiments of the invention, directional terms, such as “above,” “below,” “upper,” “lower,” etc., are used for convenience in referring to the accompanying drawings. In general, “above,” “upper,” “upward,” and similar terms refer to a direction toward the earth's surface along a wellbore, and “below,” “lower,” “downward” and similar terms refer to a direction away from the earth's surface along the wellbore.
[0074] Therefore, the present invention is well adapted to attain the ends and advantages mentioned as well as those that are inherent therein. The particular embodiments disclosed above are illustrative only, as the present invention may be modified and practiced in different but equivalent manners apparent to those skilled in the art having the benefit of the teachings herein. Furthermore, no limitations are intended due to the details of construction or design herein shown, other than as described in the claims below. It is therefore evident that the particular illustrative embodiments disclosed above may be altered, combined, or modified and all such variations are considered within the scope and spirit of the present invention. In addition, the terms in the claims have their plain, ordinary meaning unless otherwise explicitly and clearly defined by the patentee. Moreover, the indefinite articles “a” or “an,” as used in the claims, are defined herein to mean one or more than one of the elements that it introduces. If there is any conflict in the usages of a word or term in this specification and one or more patent or other documents that may be incorporated herein by reference, the definitions that are consistent with this specification should be adopted. | Systems and methods for remotely setting a downhole device. The system includes a base pipe having inner and outer radial surfaces and defining one or more pressure ports extending between the inner and outer radial surfaces. An internal sleeve is arranged against the inner radial surface and slidable between a closed position, where the internal sleeve covers the one or more pressure ports, and an open position, where the one or more pressure ports are exposed to an interior of the base pipe. A trigger housing is disposed about the base pipe and defines an atmospheric chamber in fluid communication with the one or more pressure ports. A piston port cover is disposed within the atmospheric chamber and moveable between blocking and exposed positions. A wellbore device is used to engage and move the internal sleeve into the open position by applying predetermined axial force to the internal sleeve. | 4 |
TRADEMARKS
IBM® is a registered trademark of International Business Machines Corporation, Armonk, N.Y., U.S.A. Other names used herein may be registered trademarks, trademarks or product names of International Business Machines Corporation or other companies.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to computer simulation, and particularly to using model-element-proxies to facilitate efficient analysis of simulation results.
2. Description of Background
Computer simulation of processes is widespread. Existing products, such as the WebSphere Business Modeler from IBM, allow users to simulate business processes. In the WebSphere Business Modeler, business process is modeled as a collection of tasks, non-reusable sub-processes, and calls to reusable processes with a defined execution sequence specified by connections and control structures. Each of non-reusable sub-processes may, in turn, contain tasks, other non-reusable sub-processes, and calls to reusable processes. A reusable process can be called from multiple places in the main process, any of the main process' non-reusable sub-processes and any of the main process' called reusable processes.
To further describe process modeling done in WebSphere Business Modeler and similar products, reference is made to FIG. 1 where an exemplary model is depicted. The model includes a process P 1 that includes a call to reusable sub-process P 0 (later referred to as call-to-P 0 i ). Tasks T 1 , T 2 are implemented in process P 1 . Process P 1 also includes sub-process P 2 , which includes another call to reusable sub-process P 0 (later referred to as call-to-P 0 j ). Tasks T 3 and T 4 are implemented in sub-process P 2 . Reusable sub-process P 0 includes tasks Tx 1 , Tx 2 and Tx 3 . Arrows connecting tasks/processes indicate flow of execution.
During simulation, when a given task/process is reached the instance of this task/process is created and then executed. To avoid ambiguity, elements defined in a business process (such as P 1 , P 0 , T 3 , T 4 , etc.) will be referred to as model-elements (model-tasks, model-processes), while elements created during simulation run will be referred to as element instances (task instances, process instances). Each task and process instance is uniquely identified by its own identifier, and contains a reference (such as model-element identifier) to its model-element.
When model-process P 1 is simulated, two process instances of model-sub-process P 0 are created (one created through call from P 1 instance and one by a call from P 2 instance), and corresponding task instances of model-tasks Tx 1 , Tx 2 , Tx 3 are created in both P 0 instances. Let's consider the example aggregated and percolated cost analysis report in Table 1 below. In this analysis each sub-process' cost is an aggregation of costs of all tasks and sub-processes it ultimately contains. In other words, cost is added across a sub-process level and then percolated up the containment hierarchy. It is important to notice there are two rows referring to P 0 model-sub-process (as P 0 i , and P 0 j ), each with an aggregated cost value corresponding to P 0 model-sub-process instance owned by a different super-process (which later is referred as P 0 in two different contexts). Accurately accounting for the costs of P 0 process instances and the associated tasks instances is difficult. The difficulty arises in identifying whether P 0 instance was created through a call from P 1 instance or from P 2 instance. (And similarly, in identifying whether Tx 1 , Tx 2 , Tx 3 instances were instantiated in P 0 process instance resulting from a call issued from P 1 or P 2 instance.) If aggregated and percolated cost analysis is performed on a single process instance, an algorithm simply traversing a containment tree should give acceptable performance. However, if analogous analysis is to be done for costs aggregated across multiple P 1 instances, the traversing algorithm is going to perform very poorly. (Importantly, if RDBMS was to be used to persist simulation results, there is no simple, non-recursive SQL query that could produce the above analysis if for each task/process instance all that is given is its costs, its containment data, and information on its corresponding model-task/process.)
TABLE 1
AGGREGATED
PROCESS/
COST WITH REUSABLE PROCESSES
TASK_NAME
CALCULATED IN CALLING CONTEXT
P1
c_sum(T1) + c_sum(T2) + c_sum(P0i) + c_sum(P2) +
c_sum(join)
T1
c_sum(T1)
P0i
c_sum(Tx1i) + c_sum(Tx2i) + c_sum(Tx3i)
Tx1i
c_sum(Tx1i)
Tx2i
c_sum(Tx2i)
Tx3i
c_sum(Tx3i)
P2
c_sum(T3) + c_sum(P0j) + c_sum(T4)
T3
c_sum(T3)
P0j
c_sum(Tx1j) + c_sum(Tx2j) + c_sum(Tx3j)
Tx1j
c_sum(Tx1j)
Tx2j
c_sum(Tx2j)
Tx3j
c_sum(Tx3j)
T4
c_sum(T4)
join
c_sum(join)
[c_sum(X) = sum of all costs incurred on model-element × instances]
Similarly, execution path identification algorithm that uses only containment and model-element information associated with task/process instances must traverse run-time instance containment tree for each instance of reusable process (or any of its tasks) and thus cannot be very efficient.
Thus, there is a need in the art for a technique to efficiently identify context of task/process instance creation. Among others, this technique must allow for calculation of costs incurred within a reusable process instantiated in any context without the need to traverse main process instance containment tree.
SUMMARY OF THE INVENTION
The shortcomings of the prior art are overcome and additional advantages are provided through the provision of a method of analyzing simulation results of a model, the method comprising: obtaining a process model including model elements including tasks, non-reusable sub-processes, and called reusable sub-processes; assigning a unique identifier to each model-element; generating unique model-element-proxies for all model-elements except for model elements corresponding to a model-reusable-sub-process or a model element contained by a model-reusable-sub-process; generating unique model-element-proxies for model-reusable-sub-processes and model-elements contained by model-reusable-sub-processes; associating each generated model-element-proxy with a corresponding model-element; executing simulation of the process model and persisting for each element instance data produced during simulation, the instance data including an element instance identifier and a corresponding model-element-proxy identifier; querying persisted simulation data for information using model-element-proxy identifiers.
System and computer program products corresponding to the above-summarized methods are also described and claimed herein.
Additional features and advantages are realized through the techniques of the present invention. Other embodiments and aspects of the invention are described in detail herein and are considered a part of the claimed invention. For a better understanding of the invention with advantages and features, refer to the description and to the drawings.
TECHNICAL EFFECTS
As a result of the summarized invention, technically we have achieved a solution which eliminates the need to traverse process instance containment tree for analyses that require information on task/process instance creation context. This solution provides means to efficiently calculate various costs and revenues incurred for instances of reusable processes instantiated in various calling contexts and to efficiently identify execution path taken in an overall process instance.
BRIEF DESCRIPTION OF THE DRAWINGS
The subject matter which is regarded as the invention is particularly pointed out and distinctly claimed in the claims at the conclusion of the specification. The foregoing and other objects, features, and advantages of the invention are apparent from the following detailed description taken in conjunction with the accompanying drawings in which:
FIG. 1 illustrates one example of process to be simulated; and
FIG. 2 illustrates one example of how element instances relate to model-element-proxies and how model-element-proxies, in turn, relate to model-elements.
The detailed description explains the preferred embodiments of the invention, together with advantages and features, by way of example with reference to the drawings.
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the invention relate to simulation of processes and analysis of simulation results. The simulation is typically executed on a general-purpose computer executing a computer program in response to code stored on a computer program product. The code includes instructions enabling the computer to perform the functions described herein.
The following illustrates some advantages of using model-element-proxies in the implementation where RDBMS is employed as a simulation results persistence mechanism with SQL used as a query language. The given example deals with calculation of aggregated cost values which is just one of possible applications. Conceptually, the same advantages (i.e., elimination of recursion or some expensive pre-processing) are to be realized regardless of persistence mechanism or query method.
The following example illustrates the example's model structure without using a diagram. The containment hierarchy of the model of FIG. 1 may be represented as shown in Table 2, where indentation indicates containment of one task within another.
TABLE 2
P1
T1
T2
call-to-P0i
P2
T3
call-to-P0j
T4
join
P0
Tx1
Tx2
Tx3
All model-tasks and model-processes must have unique identifiers assigned. Let's notice that P 1 does not contain P 0 directly; rather, it contains calling mechanisms (call-to-P 0 under P 1 , and under P 2 ) that refer to P 0 . If information about process model's model-tasks and model-processes is to be stored in RDBMS, it may be put into the MODEL table containing the following attributes: SIMULATION_ID which identifies the simulation run, TASK_NAME which contains the model-task name and MODEL_TASK_ID which uniquely identifies model-tasks. For the process model outlined above, entries in MODEL table might be as shown in Table 3 below.
TABLE 3
SIMULATION_ID
TASK_NAME
MODEL_TASK_ID
1
P1
1
1
T1
2
1
T2
3
1
call-to-P0i
4
1
P2
5
1
T3
6
1
call-to-P0j
7
1
T4
8
1
join
9
1
P0
10
1
Tx1
11
1
Tx2
12
1
Tx3
13
For the argument's sake let's assume that, on task instance termination, the simulation emits an event that contains the SIMULATION_ID which identifies the simulation run, PROCESS_ID which identifies the top process instance to which terminated task instance belongs, TASK_ID which uniquely identifies the task instance (assigned at run-time), MODEL_TASK_ID which identifies model-task corresponding to the task instance, PARENT_ID which identifies the instance of the process that contains the task, COST which specifies cost occurred on the task instance. It is understood that embodiments are not dependent on any particular mechanism of reporting instance specific simulation data (e.g., costs) as long as such a mechanism exists. For the process model outlined earlier, entries in a TERMINATION table that is used to store task instance termination attributes, referring to instances of model-task Tx 1 are shown in Table 4 below.
TABLE 4
SIMULATION_ID
PROCESS_ID
TASK_ID
MODEL_TASK_ID
PARENT_ID
COST
1
1
6
11
5
$1000
1
1
13
11
12
$500
1
2
23
11
22
$1000
1
2
30
11
29
$500
1
3
40
11
39
$1000
1
3
47
11
46
$500
1
4
57
11
56
$1000
1
4
64
11
63
$500
1
5
74
11
73
$1000
1
5
81
11
80
$500
The table above illustrates data that may be recorded on termination event of model-task Tx 1 instances. If a database query is used to calculate aggregated cost of all Tx 1 model-task instances that belong to P 0 instances regardless of how P 0 instance was created, the query adds up the costs for entries in TERMINATION table where MODEL_TASK_ID=11. This is a routine database query. If there is a need to calculate aggregated cost of all instances of model-tasks Tx 1 that belong to an instance of P 0 model-process that was created by the call from an instance of P 1 process-model (in the context P 1 /call-to-P 0 i /P 0 /Tx 1 ), then for each event, its grand parent event (e.g., the event twice removed from the current event) must be checked for association with P 1 . For example, for each event referring to Tx 1 model-task (MODEL_TASK_ID=11), the event that refers to its parent must be checked (by definition this parent event must refer to P 0 model-process and thus its MODEL_TASK_ID=10) if its parent (and a grand parent of the initial event) in turn refers to call-to-P 0 i (that has MODEL_TASK_ID=4 and is associated with P 1 ). Only then cost in the termination event referring to Tx 1 model-task may be included in the P 1 /call-to-P 0 i /P 0 /Tx 1 aggregated cost. In general, with events/tables defined as above, a simple SQL query that calculates aggregated cost value of a task instance contained in an instance of a reusable sub-process in the given context cannot be formulated. Either SQL query must use recursion or some expensive pre-processing must be done to determine the cost incurred in model-task Tx 1 instances that resulted from a call issued from a model-process P 1 instance.
To alleviate the problem of traversal of process instance containment tree to acquire information on task/process instance creation context, unique model-element-proxies are generated for all model-tasks and all model-non-reusable-sub-processes that are not contained in model-reusable-sub-processes; furthermore unique model-element-proxies are also generated for each context in which reusable sub-processes are used. Thus if process model contains two calls to the same model-reusable-process, then there are two proxies corresponding to the model-reusable-process itself, and to each of the model-tasks, model-non-reusable-processes it contains. For example, for P 0 model-element there are two proxies created; one for P 0 called from P 1 (by call-to-P 0 i and listed under TASK_NAME as P 0 i ) and the other for P 0 called from P 2 (by call-to-P 0 j and listed under TASK_NAME as P 0 j ). Similarly, there are two proxies for each of Tx 1 , Tx 2 , Tx 3 tasks that belong to P 0 .
For the example model outlined above, if model-element-proxies were to be stored in a PROXY table, entries in this table may be as shown in Table 5 below. MODEL_TASK_IDs are the same as those shown in Table 3. TASK_NAME column with indentation indicating containment was added to aid visualization. PROXY_TASK_IDs are defined as described in the preceding paragraph.
TABLE 5
TASK_NAME
SIMULATION_ID
PROXY_TASK_ID
MODEL_TASK_ID
P1
1
1
1
T1
1
2
2
T2
1
3
3
call-to-P0i
1
4
4
P0i
1
5
10
Tx1i
1
6
11
Tx2i
1
7
12
Tx3i
1
8
13
P2
1
9
5
T3
1
10
6
call-to-P0i
1
11
7
P0j
1
12
10
Tx1j
1
13
11
Tx2j
1
14
12
Tx3j
1
15
13
T4
1
16
8
join
1
17
9
FIG. 2 illustrates how element instances relate to model-element-proxies and how model-element-proxies, in turn, relate to model-elements. Tx 3 model-task, its model-element-proxies and its instances are depicted in FIG. 2 for sake of illustration, but it is understood that all model-elements contained in the process model may be assigned model-element-proxies
Entries in the revised TERMINATION table referring to instances of model-task Tx 1 from the process model outlined above, are shown below in Table 6. For the invention to work simulation engine must be aware of and able to report which proxy-meta-element corresponds to a given instance, which must be the case if the revised TERMINATION table is to be populated as show below.
TABLE 6
SIMULATION_ID
PROCESS_ID
TASK_ID
PROXY_TASK_ID
PARENT_ID
COST
1
1
6
6
5
$1000
1
1
13
13
12
$500
1
2
23
6
22
$1000
1
2
30
13
29
$500
1
3
40
6
39
$1000
1
3
47
13
46
$500
1
4
57
6
56
$1000
1
4
64
13
63
$500
1
5
74
6
73
$1000
1
5
81
13
80
$500
If a database query (e.g., SQL) is used to calculate aggregated cost of all Tx 1 task instances that belong to P 0 instances regardless of the context in which P 0 was created, all that is needed is to add up all cost in a table resulting from a join of the PROXY table (Table 5) and the revised TERMINATION table (Table 6) on PROXY_TASK_ID and specify MODEL_TASK_ID=11 in the where clause. As the model task identifier is 11 for both model tasks Tx 1 i and Tx 1 j , this query provides the total cost for all calls to task Tx 1 .
If a database query is needed to determine the aggregated cost of all Tx 1 task instances that belong to P 0 instances that were created through a call directly from P 1 (in the context P 1 /call-to-P 0 i /P 0 /Tx 1 ), then knowing that PROXY_TASK_ID=6 represents context P 1 /call-to-P 0 i /P 0 /Tx 1 , a query needs only to add up costs in all events containing PROXY_TASK_ID=6. There is no need for recursion in SQL or some other expensive processing.
Thus, model-element-proxies generated for model-tasks and processes allow for very significant performance improvement and much simpler algorithm design for any aggregated analysis analogous to cost analysis described above.
In alternate embodiments, input/output model-element-proxies may be used in developing more efficient and simpler set of algorithms dealing with identification of execution paths, critical/shortest path analyses, etc.
The embodiments described above are independent of any particular method of persistence or analysis. For example, model-element-proxies can simplify processing and improve performance regardless whether XML-to-flat-file or RDBMS is used for persistence, and whether XPath or plain SQL or java with SQL, or other techniques, are used for implementation of analysis algorithms.
The capabilities of the present invention can be implemented in software, firmware, hardware or some combination thereof.
As one example, one or more aspects of the present invention can be included in an article of manufacture (e.g., one or more computer program products) having, for instance, computer usable media. The media has embodied therein, for instance, computer readable program code means for providing and facilitating the capabilities of the present invention. The article of manufacture can be included as a part of a computer system or sold separately.
Additionally, at least one program storage device readable by a machine, tangibly embodying at least one program of instructions executable by the machine to perform the capabilities of the present invention can be provided.
While the preferred embodiment to the invention has been described, it will be understood that those skilled in the art, both now and in the future, may make various improvements and enhancements which fall within the scope of the claims which follow. These claims should be construed to maintain the proper protection for the invention first described. | A method of analyzing simulation results of a model, the method comprising: obtaining a process model including model elements including tasks, non-reusable sub-processes, and called reusable sub-processes; assigning a unique identifier to each model-element; generating unique model-element-proxies for all model-elements except for model elements corresponding to a model-reusable-sub-process or a model element contained by a model-reusable-sub-process; generating unique model-element-proxies for model-reusable-sub-processes and model-elements contained by model-reusable-sub-processes; associating each generated model-element-proxy with a corresponding model-element; executing simulation of the process model and persisting for each element instance data produced during simulation, the instance data including an element instance identifier and a corresponding model-element-proxy identifier; querying persisted simulation data for information using model-element-proxy identifiers. | 6 |
FIELD OF THE INVENTION
The present invention relates to a non-linear optical material comprising a particulate semiconductor having a non-linear optical effect dispersed therein and a process for the preparation thereof. More particularly, the present invention relates to a non-linear optical material comprising a particulate cuprous halide dispersed as a deposit in an organic high molecular (weight) compound or a mixed medium containing an organic high molecular compound and a process for the preparation thereof.
BACKGROUND OF THE INVENTION
With the development of data processing, the research and development of materials having a high non-linear optical effect are under way for the purpose of realizing optical logical element, optical switch, etc. as a basic technique for optical computer. As non-linear optical materials there have heretofore been known an inorganic ferroelectric material such as LiNbO 3 , BaTiO 3 and KH 2 PO 4 , a quantum well semiconductor made of GaAs or the like, an organic single crystal such as 4'-nitrobenzylidene-3-acetamino-4-methoxyaniline (MNBA) and 2-methyl-4-nitroaniline (MNA), a conjugated organic high molecular compound such as polydiacetylene and polyarylene vinylene, and semiconductor particle-dispersed glass having Cds, CdSSe, etc. dispersed in glass.
Extensive studies have been made of semiconductor particle-dispersed glass as a favorable non-linear optical material having a high non-linear optical susceptibility and a high response in combination since Jain and Lind found in 1983 that a so-called color glass filter having finely divided semiconductor particles dispersed in glass exerts a high tertiary non-linear optical effect (as disclosed in J. Opt. Soc. Am., 73, 647 (1983)).
The preparation of this type of glass is normally accomplished by a so-called melt quenching process which comprises heat-melting a mixture of glass or its starting material as a dispersant and a metal or semiconductor powder to prepare a molten glass, casting the molten glass onto a metal plate or the like so that it is rapidly cooled to the vicinity of room temperature to obtain a supercooled glass solid solution having elements constituting a semiconductor dissolved therein as ions, and then subjecting the solid solution to heat treatment at a proper temperature for a predetermined period of time to cause the precipitation of a particulate semiconductor.
However, this melt quenching process requires heating of a semiconductor material to a temperature as high as not lower than 1,000° C., causing the decomposition and evaporation of the semiconductor material. Thus, the kind of the semiconductor to which this melt quenching process can be applied and the amount of the semiconductor which can be added are limited, giving an obstacle to the realization of a material having a higher non-linear optical effect for practical use.
As another process there has been proposed a process which comprises sputtering a polycrystalline single semiconductor such as CdS and CdTe onto glass or SiO 2 as a target to prepare a semiconductor particle-dispersed glass (as disclosed in J. Appl. Phys., 63 (3), 957 (1988), JP-A-2-307832 (The term "JP-A" as used herein means an "unexamined published Japanese patent application"), etc.).
As a further process there has been proposed an evaporation or gas phase process which comprises dispersing a particulate semiconductor in a high molecular compound as a matrix other than glass (as disclosed in JP-A-3-119326, JP-A-3-140035, etc.).
These gas phase processes make it possible to dope the matrix with a semiconductor in a larger amount than in the foregoing melt quenching process. However, these gas phase processes require an expensive apparatus regardless of whether the matrix used is inorganic or organic. Further, since these gas phase processes can form a film only at a low speed, it is difficult to form a thick film although they can be used to form a thin film. Moreover, since the form of the element thus obtained is limited to thin film, its use is also limited.
As an approach for overcoming these problems there has been proposed a process which comprises allowing a particulate semiconductor or metal to be dispersed and held in a silica gel matrix produced by sol-gel method so that a semiconductor particle-dispersed glass can be prepared at a low temperature.
As such an approach there has been known a method which comprises dispersing a particulate semiconductor previously prepared by CVD method or the like in a solution of a hydrolyzation product of silicon alkoxide (sol), and then gelating the sol so that the particulate semiconductor is solidified in glass (JP-A-2-271933), a method which comprises adding a particulate semiconductor to a sol containing a silane coupling agent or allowing the particulate semiconductor to be precipitated in the sol, and then gelating the sol so that the particulate semiconductor is solidified in glass (JP-A-3-199137), a method which comprises forming a silica gel containing cadmium acetate, and then reacting the cadmium acetate with hydrogen sulfide gas to cause a particulate cadmium sulfide to be precipitated in the silica gel to obtain a semiconductor particle-dispersed glass [transactions of 1989 annual conference of the Ceramic Society of Japan, Session No. 2F20, J. Non-Cryst. Solids, 122, 101 (1990)], etc.
However, if a tetraalkoxysilane commonly used in the prior art sol-gel method is used, the material is subject to cracking at the step of drying the gel. Further, if a thin film is formed on a substrate to prepare an optical element, a sufficient thickness cannot be provided. Accordingly, in order to obtain an element having a sufficient thickness, an approach is employed which comprises applying the material to a substrate to a thickness of about 0.1 μm, calcining the thin film at a temperature of not lower than hundreds of degrees centigrade, applying the material to the film to a small thickness, and then repeating this procedure until a proper thickness is obtained.
If as the method for dispersing a particulate semiceductor in a silica gel matrix formed by sol-gel method there is used a method which comprises dispersing a particulate semiconductor which has previously been prepared by a separate method in a sol, a step of preparing a particulate semiconductor is needed, complicating the procedure. Further, a particulate semiconductor having a particle diameter of hundreds of nanometers used is remarkably difficult to handle, giving undesirable problems in the production process. Such a particulate material can be easily condensed and thus can be hardly dispersed uniformly in a medium.
JP-A-2-271933 discloses that ultrasonic dispersion or the addition of a surface active agent provides an effective improvement in the dispersion of a particulate material. However, the use of ultrasonic dispersion is disadvantageous in that the condensation of a particulate material is unavoidable during the application and drying when a thin film is formed. Further, the addition of a surface active agent is disadvantageous in that the surface active agent thus added decomposes or volatilizes away during heat treatment, causing the particulate material to be recondensed.
As a countermeasure against the foregoing problem, JP-A-3-199137 proposes that a silane coupling agent be used instead of surface active agent in an attempt to solve the problem of condensation of particulate material. This proposal features that the silane coupling agent acts like a surface active in a sol and is bonded to a matrix upon hydrolyzation. Thus, the silane coupling agent becomes thermally stable and cannot be hardly decomposed. The above cited patent also proposes as an approach for solving the handling problem of particulate semiconductor incorporated in a sol a method which comprises adding a semiconductor material in the form of solution, and then applying a paired ion source solution or reactive gas to the material to produce a particulate semiconductor in a sol. However, this method is disadvantageous in that the particulate material thus precipitated in the solution has difficulties in dispersion, making it difficult to uniformly precipitate a microcrystalline semiconductor having a quantum sizing effect. Thus, the effect of this method leaves something to be desired.
The method which comprises preparing a gel solid containing semiconductor material ions, and then subjecting the gel solid to post-treatment with hydrogen sulfide gas or the like to cause a particulate semiconductor to be precipitated has no problems of complicated regulations on handling of particulate material or no problems of ununiform dispersion but is disadvantageous in that a very toxic gas such as hydrogen sulfide must be used, endangering the workers and hence requiring a complicated procedure for safety. This method comprising a post-treatment for precipitation of a particulate material is advantageous in that it comprises uniformly dissolving in a solution a material soluble in the reaction medium as a material of particulate semiconductor or metal, making it possible to uniformly precipitate the particulate material in the medium but is disadvantageous in that there is no proper solvent depending on the materials used, restricting the concentration of the particulate material which can be added.
The sol-gel method can be effected at a lower temperature than the melt quenching process but requires heating to a temperature as high as about 600° C. Thus, in order to solve the problems of heat decomposition of semiconductor material, a process which can be operated at an even lower temperature has been desired.
On the other hand, various studies have been made also of the particulate semiconductor or metal which exerts a non-linear optical effect. In particular, studies have been made-of the use of a cuprous halide which is expected to exert a high tertiary non-linear optical effect because it produces excitons having a small Bohr diameter and thus exerts a good effect of confining excitons (Journal of Non-Crystalline Solids, 134 (1991), pp. 71-76, Journal of American Ceramic Society, 74 (1991), pp. 238-240, Journal of the Chemical Society of Japan, No. 10 (1992), pp. 1,231-1,236). However, since such a cuprous halide is not dissolved in a silane compound which has heretofore been used as a medium material, such as tetraethoxysilane [Si(OCH 2 CH 3 ) 4 ], the solvent in which the cuprous halide is dissolved is limited. Further, the cuprous halide has a low solubility. Thus, the amount of the cuprous halide which can be uniformly dissolved in the sol is very low. As a result, the particulate material can be precipitated only in a low concentration even in a gel which is the reaction product. In general, the higher the concentration of the particulate material added is, the higher is the non-linear optical effect which can be expected. Thus, a process has been desired which comprises adding a cuprous halide in a high density to obtain a material having a high non-linear optical effect.
Under the foregoing circumstances, the inventors proposed a process for providing a non-linear optical element having a particulate metal or semiconductor dispersed therein in a high density which can be used as a crackless thin film having a sufficient thickness (JP-A-7-244305). In some detail, this process comprises mixing a solution of a matrix-forming substance having a functional group with a metal, semiconductor or precursor thereof to form a uniform solution, and then allowing the functional group to undergo reaction so that a matrix is formed while causing a particulate metal or semiconductor to be precipitated in the matrix.
However, this process has some disadvantages. For example, if a material which is subject to oxidation, such as cuprous halide, is precipitated, it is partly modified by oxidation, decomposition or the like during the heat precipitation process. The resulting product is colored yellow or brown due to absorptions other than absorption by excitons in the cuprous halide. Thus, the product leaves something to be desired in optical properties.
SUMMARY OF THE INVENTION
It is therefore an object of the present invention to provide a non-linear optical material having an excellent non-linear optical effect which is insusceptible to modification of a cuprous halide incorporated therein.
It is another object of the present invention to a preparation process which enables an easy preparation of the foregoing non-linear optical material at a low temperature by means of a simple apparatus.
These and other objects of the present invention will become more apparent from the following detailed description and examples.
The inventors made extensive studies of a material capable of forming a medium for dispersing and holding a particulate cuprous halide therein. As a result, it has been found that the incorporation of a compound for inhibiting the modification of a cuprous halide in a matrix-forming substance makes it possible to produce a non-linear optical material having excellent optical properties. The present invention has thus been worked out.
The present invention concerns a non-linear optical material which exhibits a nonlinear response to incident light, comprising a particulate cuprous halide dispersed in a matrix, the particulate cuprous halide having been separated out with the reaction of a functional group contained in a functional group-containing matrix-forming substance, wherein the matrix contains a compound for inhibiting the modification of the cuprous halide.
The present invention also concerns a process for the preparation of a non-linear optical material which exhibits a non-linear response to incident light, which comprises mixing a mixture of a functional group-containing matrix-forming substance and a compound for inhibiting the modification of a cuprous halide with a cuprous halide to form a uniform solution, and then allowing the functional group to undergo reaction to form a matrix while causing a particulate cuprous halide to separate out in the matrix.
In the present invention, a cuprous halide, a matrix-forming substance such as high molecular and low molecular compound having a functional group and a compound for inhibiting the modification of a cuprous halide are mixed so that the functional group is reacted to cause the precipitation of a cuprous halide which is insusceptible to modification such as oxidation and decomposition.
The term "matrix-forming substance having a functional group" as used herein is meant to indicate a substance which comprises at least one high molecular or low molecular compound having a functional group and one compound for inhibiting the modification of a cuprous halide and eventually forms a matrix. In other words, a matrix-forming substance having a functional group is a substance which forms an inorganic high molecular compound, an organic high molecular compound and a low molecular compound to be contained in the matrix that is finally formed after the reaction of the functional group. It is a substance which forms various components except particulate cuprous halide in the final composition. In order to adjust physical properties such as mechanical properties, refractive index and dielectric constant, the matrix-forming substance may be used in admixture with a high molecular compound free of functional group, etc.
The term "reaction of a functional group" as used herein is meant to indicate a reaction which lessens or eliminates the interaction between the cuprous halide and the functional group to accelerate the precipitation of the cuprous halide. Before the reaction of the functional group, the interaction between the functional group and the cuprous halide is effected to help the dissolution and hence accelerate doping. After the reaction of the functional group, the precipitation of a particulate cuprous halide is accelerated. The kind and reaction of the functional group are not specifically limited so far as the foregoing requirements are satisfied. For example, various reactions disclosed in JP-A-7-244305 may be used. Examples of the functional group to be reacted include carboxyl group, amino group, amide group, and hydroxyl group. Examples of the reaction of the functional group include intramolecular or intermolecular cyclization reaction, condensation reaction, addition reaction and elimination reaction that causes structural change. These reactions are caused by the action of heat or light, or by a chemical treatment in the presence of a catalyst.
These reactions can be roughly divided into some groups: (1) imide ring-forming reaction by heat treatment or chemical treatment, (2) reaction of a functional group such as carboxyl group, amino group, hydroxyl group and carboxylate anhydride group with an isocyanate group or epoxy group, (3) acid-added salt forming reaction by processing an amino compound with an acid, and (4) other reactions.
An embodiment of the non-linear optical material of the present invention will be exemplified hereinafter. This embodiment is a dispersion of a particulate cuprous halide in a matrix comprising a high molecular compound produced by heat curing or chemical treatment, particularly a high molecular compound having a repeating structural unit represented by the following general formula (1), and a compound for inhibiting the modification of the cuprous halide, such as oxidation inhibitor. ##STR1## wherein X represents a tetravalent organic group having not less than 2 carbon atoms; and Y represents a divalent organic group having not less than 2 carbon atoms.
The preparation of the non-linear optical material of the present invention can be accomplished by a process which comprises mixing a mixed solution containing a matrix-forming substance having at least a functional group which interacts with a cuprous halide to help dissolve the cuprous halide, e.g., high molecular compound, and a compound for inhibiting the modification of the cuprous halide, e.g., oxidation inhibitor, with a cuprous halide to form a uniform solution, removing the solvent therefrom, and then subjecting the mixture to heat treatment or chemical treatment.
A preferred embodiment of the non-linear optical material of the present invention is produced by a process which comprises subjecting a heat-curable material, particularly a high molecular compound having a repeating structural unit represented by the following general formula (2), to heat treatment or chemical treatment as a matrix-forming substance having a functional group to allow a particulate cuprous halide to be precipitated. ##STR2## wherein X represents a tetravalent organic group having not less than 2 carbon atoms; and Y represents a divalent organic group having not less than 2 carbon atoms.
BRIEF DESCRIPTION OF THE DRAWINGS
By way of example and to make the description more clear, reference is made to the accompanying drawings in which:
FIG. 1 illustrates X-ray diffraction spectrum of the high molecular compound/CuCl composite film of Example 1 (using CuKα X-ray);
FIG. 2 illustrates the absorption spectrum of the high molecular compound/CuCl composite film of Example 1;
FIG. 3 illustrates X-ray diffraction spectrum of the high molecular compound/CuCl composite film of Comparative Example 1 (using CuKα X-ray);
FIG. 4 illustrates the absorption spectrum of the high molecular compound/CuCl composite film of Comparative Example 1;
FIG. 5 illustrates X-ray diffraction spectrum of the high molecular compound/CuBr composite film of Example 4 (using CuKα X-ray);
FIG. 6 illustrates the absorption spectrum of the high molecular compound/CuBr composite film of Example 4;
FIG. 7 illustrates X-ray diffraction spectrum of the high molecular compound/CuBr composite film of Comparative Example 2 (using CuKα X-ray); and
FIG. 8 illustrates the absorption spectrum of the high molecular compound/CuBr composite film of Comparative Example 2.
DETAILED DESCRIPTION OF THE INVENTION
The present invention will be further described hereinafter.
Referring further to the high molecular compound having a repeating structural unit represented by the foregoing general formula (2) to be used herein as a precursor from which the foregoing matrix is produced, X may be exemplified as an organic residue represented by the following structural formula: ##STR3## (wherein k represents an integer of from 1 to 6) Y may be exemplified as an organic residue represented by the following structural formula: ##STR4## (wherein a represents an integer of from 1 to 1,000)
The high molecular compounds thus exemplified can be synthesized from a tetracarboxylic dihydrate having a structure represented by X and a diamine having a structure represented by Y. These high molecular compounds are soluble in a polar organic solvent such as dimethylformamide, dimethylacetamide, n-methylpyrrolidone, dimethyl sulfoxide, dimethyl sulfonamide, m-cresol, p-chlorophenol, dimethyl imidazoline, tetramethylurea, diglyme, triglyme and tetraglyme. Thus, these high molecular compounds may be formed into a film by a coating method such as spin coating and dip coating. These molecular compounds may also be worked into a fiber. These high molecular compounds preferably have an intrinsic viscosity [η] of from 0.1 to 6 dl/g in a solvent such as dimethylacetamide at 30° C. The term "intrinsic viscosity" as used herein is meant to indicate a value determined by extrapolating the relative or reduced viscosity calculated from the measurements of relative viscosity at various polymer concentrations to zero concentration. Further, these high molecular compounds have many amide acid structures as functional groups and thus interact with various inorganic elements and inorganic compounds. Therefore, these high molecular compounds can stably dissolve a metal, a semiconductor or a compound as starting material thereof therein in a relatively high concentration when they are in the form of either solution or solid freed of solvent. Further, when these high molecular compounds are subjected to heat treatment or dipped in a mixture of acetic anhydride and pyridine to undergo chemical treatment, the following reaction occurs. The mixing ratio of acetic anhydride and pyridine in the mixture of solvent is preferably about 1:1 (by volume). ##STR5## (wherein n represents a polymerization degree)
The heat treatment may be effected at a temperature of from 50° C. to 400° C., preferably from 100° C. to 300° C. As the solvent to be used in the foregoing chemical treatment there may be used a mixture of acetic anhydride, pyridine and benzene, a mixture of acetic anhydride, pyridine and dimethylacetamide or the like besides the above mentioned mixed solvent.
The foregoing dissolution, heat treatment and chemical treatment are preferably effected in vacuo or in an inert atmosphere.
When the foregoing reaction occurs, the amide acid structure contained in the high molecular compound, i.e., matrix disappears, accompanied by the formation of an imide ring structure as well as the precipitation of the dopant dissolved in the high molecular compound, i.e., cuprous halide. In order to adjust the physical properties such as mechanical properties, refractive index and dielectric constant of the matrix, the foregoing high molecular compound may be used in admixture with other high molecular compounds.
As the particulate cuprous halide to be precipitated in the matrix herein there may be used any material which exhibits non-linear optical properties. Examples of such a material include CuCl, CuBr and CuI in the particulate form. Such a material is incorporated in an amount of from 0.01 to 99% by weight, preferably from 0.1 to 95% by weight.
The non-linear optical material of the present invention comprises as a material which exerts a non-linear optical effect a particulate cuprous halide which produces excitons having a small Bohr diameter and thus exerts a good effect of confining excitons. Accordingly, the non-linear optical material of the present invention is expected to exert a great tertiary non-linear optical effect.
The compound for inhibiting the modification of a cuprous halide employable herein is not specifically limited but is preferably a compound which inhibits the modification of a cuprous halide, shows a good solubility in the same solvent as for the matrix-forming substance having a functional group having an interaction with a cuprous halide and exhibits a sufficiently small absorption in the wavelength of light used by itself and heating product, i.e., wavelength range where the cuprous halide exerts a great non-linear optical effect.
Examples of such a compound include various oxidation inhibitors such as quinone (e.g., hydroquinone), phenol (e.g., BHT (2,6-di-t-butyl-4-methylphenol), BHA (t-butylhydroxyanisole)) and phosphorous acid ester (e.g., triphenyl phosphate). Further, a synergist which exerts no effect of inhibiting oxidation itself but does in the presence of an oxidation inhibitor, such as ascorbic acid, citric acid and phosphoric acid, or a coloration inhibitor for inhibiting the coloration of an oxidation product of an oxidation inhibitor may be used as well. Other examples of the compound for inhibiting the modification of a cuprous halide include various reducing agents such as lower oxygen acid (e.g., sulfite) and metal salt in the form of low atomic valence (e.g., FeCl 2 , SnCl 2 , CrCl 2 , VCl 2 ). Among these reducing agents, SnCl 2 effectively inhibits the modification of a cuprous halide, and its oxidation product SnO 2 is colorless. Further, since SnCl 2 forms no crystalline particles even after heated, a high transparency can be maintained. Accordingly, SnCl 2 can be used as the most effective compound in the present invention.
The compound for inhibiting the modification of a cuprous halide is incorporated in the system in an amount of from 0.01 to 99% by weight, preferably from 0.1 to 95% by weight.
In the process for the preparation of the non-linear optical material of the present invention, the solution preparation step of dissolving a cuprous halide in a solution containing a high molecular compound, the step of applying the solution thus obtained, the step of removing the solvent from the coating, the step of subjecting the high molecular compound to heat treatment or chemical treatment, and other steps are all preferably effected in an inert atmosphere such as nitrogen and argon.
The present invention will be further described hereinafter.
EXAMPLE 1
In a stream of dried nitrogen, 0.498 g of 2,2-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane represented by the following general formula (3) was dissolved in 100 ml of diemthylacetamide to make a complete solution to which 0.431 g of 4,4, '-(hexafluoroisopropylidene)phthalic anhydride represented by the following general formula (4) was then gradually added. Subsequently, in a stream of dried nitrogen, the mixture was slowly stirred while being kept at a temperature of from 10° C. to 15° C. for 1 hour. The mixture was further stirred while being kept at a temperature of from 20° C. to 25° C. for 2 hours to obtain a solution of a high molecular compound represented by the following general formula (5). In the high molecular compound solution was then dissolved 0.28 g of SnCl 2 to obtain an almost colorless and transparent solution. To the solution was then added 0.15 g of CuCl. The mixture was then stirred to obtain a light yellowish green transparent solution. The foregoing stirring steps were all effected in an atmosphere of dried nitrogen. ##STR6## (wherein n' represents an integer of about 300)
The solution thus obtained was then spin-coated onto a glass substrate in an atmosphere of dried nitrogen to obtain a colorless and transparent film. The film thus obtained was then subjected to heat treatment at a temperature of 250° C. under a pressure of 1×10 -5 torr for 30 minutes. The film thus treated was then examined for the presence of precipitate by X-ray diffractometry. As a result, it was confirmed that the foregoing heat treatment had caused the precipitation of CuCl (see FIG. 1). No crystals other than CuCl were observed precipitated.
The particle diameter of the precipitate was determined by a transmission electron microscope. As a result, it was confirmed to be from 10 to 50 nm. The high molecular compound/CuCl composite film thus obtained had a sufficiently small precipitate particle diameter and thus was transparent and colorless. The absorption spectrum of the film is shown in FIG. 2. The measurement of absorption spectrum was conducted at room temperature. A Z 12 exciton absorption sub-band structure of CuCl was definitely observed at 372 nm. A Z 3 exciton absorption sub-band structure of CuCl was definitely observed at 380.sup.• nm. As indications of the comparison between absorption by exciton and other undesirable absorptions, the ratio of the absorbance of Z 12 exciton absorption to the absorbance at 500 nm (Abs (exciton)/Abs (500 nm)), the ratio of the absorbance of Z 12 exciton absorption to the absorbance at 400 nm (Abs (exciton)/Abs (400 nm)), and the ratio of the absorbance of Z 12 exciton absorption to the absorbance at 350 nm (Abs (exciton)/Abs (350 nm)) were calculated. The results are set forth in Table 1.
Comparative Example 1
The procedure of Example 1 was followed to prepare a solution of a high molecular compound represented by the foregoing general formula (5). To the high molecular compound solution thus obtained was then added 0.15 g of CuCl. The mixture was then stirred to obtain a bluish green transparent solution. The foregoing stirring steps were all conducted in an atmosphere of dried nitrogen.
The solution thus obtained was then spin-coated onto a glass substrate in an atmosphere of dried nitrogen to obtain a light bluish green transparent film. The film thus obtained was then subjected to heat treatment at a temperature of 250° C. under a pressure of 1×10 -5 torr for 30 minutes. The film thus treated was then examined for the presence of precipitate by X-ray diffractometry. As a result, it was confirmed that the foregoing heat treatment had caused the precipitation of CuCl (see FIG. 3). No crystals other than CuCl were observed precipitated.
The particle diameter of the precipitate was determined by a transmission electron microscope. As a result, it was confirmed to be from 10 to 50 nm. The high molecular compound/CuCl composite film thus obtained had a sufficiently small precipitate particle diameter and thus was transparent but observed colored light yellowish brown. The absorption spectrum of the film is shown in FIG. 4. The measurement of absorption spectrum was conducted at room temperature. A Z 12 exciton absorption sub-band structure of CuCl was definitely observed at 367 nm. A Z 3 exciton absorption sub-band structure of CuCl was definitely observed at 380 nm. However, these sub-band structures were observed less definitely than Example 1. Due to a very broad absorption extending to long wavelength side other than exciton absorption, absorption was observed all over the wavelength range where the measurement was conducted. As indications of the comparison between absorption by exciton and other undesirable absorptions, Abs (exciton)/Abs (500 nm), Abs (exciton)/Abs (400 nm), and Abs (exciton)/Abs (350 nm) were calculated as in Example 1. The results are set forth in Table 1. As compared with Example 1, the sample of this comparative example had definitely small such indication values and thus exhibited poor optical properties.
EXAMPLE 2
The procedure of Example 1 was followed to prepare a solution of a high molecular compound represented by the foregoing general formula (5). To the high molecular compound solution thus obtained was then added 0.05 g of BHT (2,6-di-t-butyl-4-methylphenol) to obtain a colorless and transparent solution. To the solution was then added 0.15 g of CuCl. The mixture was then stirred to obtain a light yellowish green solution. The foregoing stirring steps were all conducted in an atmosphere of dried nitrogen.
The solution thus obtained was then spin-coated onto a glass substrate in an atmosphere of dried nitrogen to obtain a colorless and transparent film. The film thus obtained was then subjected to heat treatment at a temperature of 250° C. under a pressure of 1×10 -5 torr for 30 minutes. The film thus treated was then examined for the presence of precipitate by X-ray diffractometry. As a result, it was confirmed that the foregoing heat treatment had caused the precipitation of CuCl. No crystals other than CuCl were observed precipitated. The high molecular compound/CuCl composite film thus obtained had a sufficiently small precipitate particle diameter and thus was transparent and light yellowish. The absorption spectrum of the film was measured at room temperature. As a result, a Z 12 exciton absorption sub-band structure of CuCl was definitely observed at 372 nm. A Z 3 exciton absorption sub-band structure of CuCl was definitely observed at 380 nm. As indications of the comparison between absorption by exciton and other undesirable absorptions, Abs (exciton)/Abs (500 nm), Abs (exciton)/Abs (400 nm), and Abs (exciton)/Abs (350 nm) were calculated as in Example 1. The results are set forth in Table 1.
EXAMPLE 3
The procedure of Example 1 was followed to prepare a solution of a high molecular compound represented by the foregoing general formula (5). In the high molecular compound solution thus obtained was then dissolved 0.05 g of triphenyl phosphite to obtain a colorless and transparent solution. To the solution was then added 0.15 g of CuCl. The mixture was then stirred to obtain a transparent light yellowish green solution. The foregoing stirring steps were all conducted in an atmosphere of dried nitrogen.
The solution thus obtained was then spin-coated onto a glass substrate in an atmosphere of dried nitrogen to obtain a colorless and transparent film. The film thus obtained was then subjected to heat treatment at a temperature of 250° C. under a pressure of 1×10 -5 torr for 30 minutes. The film thus treated was then examined for the presence of precipitate by X-ray diffractometry. As a result, it was confirmed that the foregoing heat treatment had caused the precipitation of CuCl. No crystals other than CuCl were observed precipitated. The high molecular compound/CuCl composite film thus obtained had a sufficiently small precipitate particle diameter and thus was transparent and light yellowish. The absorption spectrum of the film was measured at room temperature. As a result, a Z 12 exciton absorption sub-band structure of CuCl was definitely observed at 372 nm. A Z 3 exciton absorption sub-band structure of CuCl was definitely observed at 380 nm. As indications of the comparison between absorption by exciton and other undesirable absorptions, Abs (exciton)/Abs (500 nm), Abs (exciton)/Abs (400 nm), and Abs (exciton)/Abs (350 nm) were calculated as in Example 1. The results are set forth in Table 1.
TABLE 1______________________________________ Abs(exciton)/ Abs(exciton)/ Abs(exciton)/ Example No. Abs(500 nm) Abs(400 nm) Abs(350 nm)______________________________________Example 1 6.8 5.67 1.48 Example 2 11.1 1.92 1.28 Example 3 7.69 2.49 1.31 Comparative 2.56 1.88 1.04 Example 1______________________________________
EXAMPLE 4
The procedure of Example 1 was followed to prepare a solution of a high molecular compound represented by the foregoing general formula (5). In the high molecular compound solution thus obtained was then dissolved 0.28 g of SnCl 2 to obtain an almost colorless and transparent solution. To the solution was then added 0.22 g of CuBr. The mixture was then stirred to obtain a transparent light yellowish green solution. The foregoing stirring steps were all conducted in an atmosphere of dried nitrogen.
The solution thus obtained was then spin-coated onto a glass substrate in an atmosphere of dried nitrogen to obtain a light yellowish green transparent film. The film thus obtained was then subjected to heat treatment at a temperature of 250° C. under a pressure of 1×10 -5 torr for 30 minutes. The film thus treated was then examined for the presence of precipitate by X-ray diffractometry. As a result, it was confirmed that the foregoing heat treatment had caused the precipitation of CuBr (see FIG. 5). No crystals other than CuCl were observed precipitated. The high molecular compound/CuBr composite film thus obtained had a sufficiently small precipitate particle diameter and thus was transparent and light yellowish. The absorption spectrum of the film is shown in FIG. 6. The measurement of absorption spectrum was conducted at room temperature. As a result, a Z 12 exciton absorption sub-band structure of CuBr was definitely observed at 410 nm. A Z 3 exciton absorption sub-band structure of CuBr was definitely observed at 390 nm. As indications of the comparison between absorption by exciton and other undesirable absorptions, Abs (exciton)/Abs (500 nm), Abs (exciton)/Abs (450 nm), and Abs (exciton)/Abs (400 nm) were calculated as in Example 1. The results are set forth in Table 2.
Comparative Example 2
The procedure of Example 1 was followed to prepare a solution of a high molecular compound represented by the foregoing general formula (5). To the high molecular compound solution thus obtained was then added 0.22 g of CuBr. The mixture was then stirred to obtain a bluish green transparent solution. The foregoing stirring steps were all conducted in an atmosphere of dried nitrogen.
The solution thus obtained was then spin-coated onto a glass substrate in an atmosphere of dried nitrogen to obtain a light bluish green transparent film. The film thus obtained was then subjected to heat treatment at a temperature of 250° C. under a pressure of 1×10 -5 torr for 30 minutes. The film thus treated was then examined for the presence of precipitate by X-ray diffractometry. As a result, it was confirmed that the foregoing heat treatment had caused the precipitation of CuBr (see FIG. 7). No crystals other than CuBr were observed precipitated. The high molecular compound/CuBr composite film thus obtained had a sufficiently small precipitate particle diameter and thus was transparent but observed colored yellowish brown. The absorption spectrum of the film is shown in FIG. 8. The measurement of absorption spectrum was conducted at room temperature. A Z 12 exciton absorption sub-band structure of CuBr was definitely observed at 410 nm. A Z 3 exciton absorption sub-band structure of CuBr was definitely observed at 390 nm. However, these sub-band structures were observed less definitely than Example 4. Due to a very broad absorption extending to long wavelength side other than exciton absorption, absorption was observed all over the wavelength range where the measurement was conducted. As indications of the comparison between absorption by exciton and other undesirable absorptions, Abs (exciton)/Abs (500 nm), Abs (exciton)/Abs (450 nm), and Abs (exciton)/Abs (400 nm) were calculated as in Example 1. The results are set forth in Table 2. As compared with Example 4, the sample of this comparative example had definitely small such indication values and thus exhibited poor optical properties.
EXAMPLE 5
The procedure of Example 1 was followed to prepare a solution of a high molecular compound represented by the foregoing general formula (5). To the high molecular compound solution thus obtained was then added 0.05 g of BHT (2,6-di-t-butyl-4-methylphenol) to obtain a colorless and transparent solution. To the solution was then added 0.22 g of CuBr. The mixture was then stirred to obtain a light yellowish green solution. The foregoing stirring steps were all conducted in an atmosphere of dried nitrogen.
The solution thus obtained was then spin-coated onto a glass substrate in an atmosphere of dried nitrogen to obtain a colorless and transparent film. The film thus obtained was then subjected to heat treatment at a temperature of 250° C. under a pressure of 1×10 -5 torr for 30 minutes. The film thus treated was then examined for the presence of precipitate by X-ray diffractometry. As a result, it was confirmed that the foregoing heat treatment had caused the precipitation of CuBr. No crystals other than CuBr were observed precipitated. The high molecular compound/CuBr composite film thus obtained had a sufficiently small precipitate particle diameter and thus was transparent and light-yellowish. The absorption spectrum of the film was measured at room temperature. As a result, a Z 12 exciton absorption sub-band structure of CuBr was definitely observed at 410 nm. A Z 3 exciton absorption sub-band structure of CuBr was definitely observed at 390 nm. As indications of the comparison between absorption by exciton and other undesirable absorptions, Abs (exciton)/Abs (500 nm), Abs (exciton)/Abs (450 nm), and Abs (exciton)/Abs (400 nm) were calculated as in Example 1. The results are set forth in Table 2.
EXAMPLE 6
The procedure of Example 1 was followed to prepare a solution of a high molecular compound represented by the foregoing general formula (5). In the high molecular compound solution thus obtained was then dissolved 0.05 g of triphenyl phosphite to obtain a colorless and transparent solution. To the solution was then added 0.22 g of CuBr. The mixture was then stirred to obtain a transparent light yellowish green solution. The foregoing stirring steps were all conducted in an atmosphere of dried nitrogen.
The solution thus obtained was then spin-coated onto a glass substrate in an atmosphere of dried nitrogen to obtain a colorless and transparent film. The film thus obtained was then subjected to heat treatment at a temperature of 250° C. under a pressure of 1×10 -5 torr for 30 minutes. The film thus treated was then examined for the presence of precipitate by X-ray diffractometry. As a result, it was confirmed that the foregoing heat treatment had caused the precipitation of CuBr. No crystals other than CuBr were observed precipitated. The high molecular compound/CuBr composite film thus obtained had a sufficiently small precipitate particle diameter and thus was transparent and light yellowish. The absorption spectrum of the film was measured at room temperature. As a result, a Z 12 exciton absorption sub-band structure of CuBr was definitely observed at 410 nm. A Z 3 exciton absorption sub-band structure of CuBr was definitely observed at 390 nm. As indications of the comparison between absorption by exciton and other undesirable absorptions, Abs (exciton)/Abs (500 nm), Abs (exciton)/Abs (450 nm), and Abs (exciton)/Abs (400 nm) were calculated as in Example 1. The results are set forth in Table 2.
TABLE 2______________________________________ Abs(exciton)/ Abs(exciton)/ Abs(exciton)/ Example No. Abs(500 nm) Abs(450 nm) Abs(400 nm)______________________________________Example 4 12.80 6.76 1.54 Example 5 9.3 6.01 1.38 Example 6 8.78 6.55 1.42 Comparative 4.41 3.88 1.03 Example 2______________________________________
As mentioned above, the non-linear optical material of the present invention comprises a particulate cuprous halide having a high non-linear optical effect precipitated by the change of a functional group in a matrix, stably dispersed in the matrix in a high concentration without being subject to modification by oxidation or the like. Accordingly, when applied to a substrate to form a thin film, the non-linear optical material of the present invention acts as a crackless non-linear optical element having a sufficient thickness which exerts a high non-linear optical effect. Further, the non-linear optical material of the present invention exerts a high non-linear optical effect and exhibits a high mechanical strength and an excellent optical transparency can be effectively used in the art of optoelectronics. For example, it can be used as an optical switch, optical memory, etc. It can also be used for conversion of wavelength, automatic correction of optical system, optical computing, etc.
In accordance with the preparation process of the present invention, a non-linear optical material can be easily prepared at a low temperature. Further, this preparation process enables the preparation of a functional gel starting with a solution and thus requires no complicated procedure. The gel thus prepared can be easily deformed. Accordingly, the gel can be formed in any shape such as film, tablet, block and fiber.
While the invention has been described in detail and with reference to specific embodiments thereof, it will be apparent to one skilled in the art that various changes and modifications can be made therein without departing from the spirit and scope thereof. | The present invention provides a non-linear optical material having an excellent non-linear optical effect which is insusceptible to modification of a cuprous halide incorporated therein. The present invention also provides a process which enables the preparation of such a non-linear optical material at a low temperature by means of a simple apparatus. The non-linear optical material of the present invention exhibits a nonlinear response to incident light and comprises a particulate cuprous halide dispersed in a matrix, said particulate cuprous halide having been separated out with the reaction of a functional group contained in a matrix-forming substance having a functional group, wherein said matrix contains a compound for inhibiting the modification of said cuprous halide. The preparation of the non-linear optical material of the present invention can be accomplished by a process which comprises mixing a mixture of a matrix-forming substance having a functional group and a compound for inhibiting the modification of a cuprous halide with a cuprous halide to form a uniform solution, and then allowing said functional group to undergo reaction to form a matrix while causing a particulate cuprous halide to separate out in said matrix. | 2 |
CROSS-REFERENCE TO RELATED APPLICATIONS
U.S. Pat. No. 6,470,633 B2, dated Oct. 29, 2002, entitled Circular Subdivisions, issued to this Applicant. This prior Patent should be reviewed with the review of this application because this application deals with amplifications of the concepts described in the prior Patent.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
Not Applicable.
REFERENCE TO A MICROFICHE APPENDIX
Not Applicable.
BACKGROUND OF THE INVENTION
The field of endeavor to which my invention pertains is real estate subdivision and development, with references to appropriate residential, office, commercial and industrial construction techniques.
I previously hired a patent search company to investigate prior art and they concluded that the following U.S. patents were most relevant to my disclosure:
U.S. Pat. No. 4,679,363 discloses a township, city and regional land arrangement with housing and commercial buildings having a plurality of circular roadways.
U.S. Pat. No. 4,920,711 discloses a building construction system which is arranged in four 90 degree quadrants.
U.S. Pat. No. 4,852,313 discloses a building arrangement and method for view site; said arrangement maximizes the number of houses with a line of site to a view.
None of the foregoing patents, however, remotely approximate the combination of development circles, surrounded by traffic circles, all connected together by a pattern of one-way streets, the subject matter of my prior Patent and this application.
BRIEF SUMMARY OF THE INVENTION
Although reference was made to condominiums in the prior Patent, most comments dealt with detached or attached single-family residences. This application is based upon the recognition that the principal use of Circular Subdivisions may be for entire walkable communities. In the prior Patent, the parking lanes did not extend into the traffic circles or beyond them. In this application, the parking lanes have been converted into combination parking and bicycle lanes that extend into the development circles, the traffic circles, the entries, the exits and the arterial service roads and traffic circles outside the Bobstown Villages development ( FIG. 3 ).
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
FIG. 1 —Depicts Circular Subdivision detached single-family residences with the auto traffic in the automobile lanes and the bicycle traffic in the combination parking and bicycle lanes, each proceeding in opposite directions.
FIG. 2 —Depicts only the central row of the development circles on FIG. 1 , making the traffic arrows easier to read.
FIG. 3 —Depicts an entire walkable community, Bobstown Villages, for about 20,000 residents, all of whom are only a short walk (no more than one-quarter mile) from their private or government offices, stores, theaters, high-rise residential condominiums, restaurants, parking garages, hospitals, schools, churches, etc., in the center of the community.
FIG. 4 —Depicts a typical Circular Subdivision two-story residential condominium area with one large park and four smaller parks in the center. These represent the twenty-eight low-rise residential areas in the Bobstown Villages development ( FIG. 3 ) that surround the high-rise downtown area in the center of the community.
DETAILED DESCRIPTION OF THE INVENTION
1. The Concept
My original objections and solutions in the prior Patent dealt primarily with detached and attached (technically zero lot line) single-family residences. Before long I realized that the zero lot line residences depicted in the application for my prior Patent could easily be extended in each of the four perpendicular directions to provide construction space for sixteen true two-story condominiums on the same development circle housing only four zero lot line residences.
Ultimately I realized that our housing problems were much broader and began to think about prevention of urban sprawl, affordability of housing, bicycle safety, and environmental and health issues such as air and river pollution, water conservation, global warming, and inactivity and obesity problems of adults and children. Each of the eight substantive issues described in the preceding sentence are discussed separately in the following numbered paragraphs.
2. Prevention of Urban Sprawl
Many jurisdictions are now trying to prevent further urban sprawl by surrounding existing cities with urban development boundaries that require future development to take place in existing cities. These urban development boundaries do have a temporary effect of preventing developments in adjacent farms, ranches, etc., but before long the problems that caused residents to flee the cities in first place, i.e., inadequate schools, inadequate transportation, inadequate parking, and inadequate parks and recreation areas, cause the urban development boundaries to be amended and often replaced, unfortunately, by further urban sprawl developments.
Recognizing a few exceptions such as developments of large homes for wealthy individuals surrounding a golf course, further urban sprawl developments should not be built in existing cities or in their adjacent farms, ranches, etc. Further developments need to be compact, efficient, affordable and safe, as shown in the Bobstown Villages development ( FIG. 3 ).
I recently did a study for a project near Denver, Colo. The existing population of Denver is spread over an area of a little less than 160 square miles. By using the concepts depicted in the Bobstown Villages ( FIG. 3 ), that same entire population of Denver could live and work in an area of about 16 square miles, a reduction in required land use of almost 90%.
3. Affordability of Housing
From a development standpoint each development circle will yield about four single-family detached homes per acre, about sixteen condominium homes per acre (all with attached enclosed garages), or one high-rise building for residential, or office or commercial purposes. At this time when affordable housing and loss of open space rank highest among the concerns of both public officials and private citizens, this subsequently discussed ability to produce fourteen to sixteen attractive two-story condominium homes per acre surrounded by 75% open space probably will be one of the most important uses of Circular Subdivisions.
Although the condominiums surrounding the park depicted in FIG. 4 are only two stories tall the population density is about the same that exists in New York City, i.e., more than 25,000 residents per square mile. However, the Bobstown Villages development ( FIG. 3 ) low-rise condominiums are surrounded by about 50% recreational parks and other landscaped areas while the tall buildings in New York City have only about 17% or 18% recreational parks and other landscaped areas (mostly concentrated in one Central Park).
Having such an abundance of landscaped areas immediately available for exercise and play ( FIG. 4 ) is a tremendous advantage for the Bobstown Villages development ( FIG. 3 ) low-rise condominiums at a time when inactivity and obesity are serious national problems in the United States for both adults and children. The larger park in the center of the 128 low-rise residential condominiums is of sufficient size to accommodate such sports as soccer, lacrosse, field hockey, flag football, and in colder areas even ice-skating. The smaller parks in the center, and around the edges, of the 128 low-rise residential condominiums will accommodate such activities as sand boxes for small children and their parents, volleyball, badminton, horseshoes, etc.
Consistent with the Bobstown Villages development's ( FIG. 3 ) underlying concept of creating neighborhoods in which residents get to know their neighbors, the cut-in system will be used to eliminate long waiting times in the recreational park areas described in the preceding paragraph. For example, a full complement of six players on each side are involved in a volleyball game. During the game, four newcomers arrive and wait. At the end of the game, the captain of the losing team has the first pick and the captain of the winning team has the second pick, until all four newcomers have been chosen to replace the two players on each team who have been playing for the longest time. The four replaced players are then treated as newcomers at the end of the next game. This assures that no player will have to sit out for very long.
Because of the circular configurations of the development circles, the traffic circles, and the combination bicycle and parking circles, the eight 1,000 square foot two bedroom, two bath lower floor condominiums, and the eight 1,500 square foot three bedroom, three bath upper floor condominiums, that are contained in each development circle ( FIG. 4 ), provide attractive affordable housing with an unheard of amount of open space, but, at the same time, reduce the loss of open space in the surrounding area because the Circular Subdivision condominiums around a park plan requires the development of only 25% of the open space that would be required to develop a conventional detached home rectangular subdivision housing the same number of residents, thus leaving 75% of the surrounding open space to continue to be used for agriculture, forestry, ranching, etc.
The basic idea in the Bobstown Villages development ( FIG. 3 ) is that there are a number of neighborhoods in increasing sizes. Each of the four pie-shaped lawn areas surrounding the low-rise condominiums is a neighborhood for four families. Each module of low-rise condominiums is a neighborhood for one hundred twenty-eight families. Each 270-acre Bobstown Villages development ( FIG. 3 ) is a neighborhood for almost five thousand families.
4. Bicycle Safety Provisions
My application for the original Circular Subdivision patent made no reference to bicycle lanes of any sort. Even the automobile parking lanes surrounded only the development circles, not the traffic circles or beyond. As the other substantive issues in these numbered paragraphs were considered, bicycles and bicycle safety became an essential ingredient in the mix and were made possible by the elimination of automobiles as the main means of transportation.
In fact, one of my studies concluded that, by using the concepts in the Bobstown Villages development ( FIG. 3 ), an area six miles wide and six miles deep (easy distances for bicycles) would be large enough to employ a sizable part of, and house all of, over one million residents.
FIG. 1 depicts Circular Subdivision detached single-family residences with the auto traffic in the automobile lanes and the bicycle traffic in the combination parking and bicycle lanes, each proceeding in opposite directions. FIG. 2 depicts only the central row of the development circles on FIG. 1 , making the traffic arrows easier to read. Combining automobile traffic and bicycle traffic creates serious problems for both the auto driver and the cyclist.
Today most jurisdictions have any bicycle lane parallel to, and to the right side of, the automobile lane, with the traffic in both lanes proceeding in the same direction. The auto driver cannot be certain that the cyclist has seen the auto until the auto is already past the bicycle. The cyclist cannot be aware of the auto until it appears in the dentist's tooth-mirror that is glued to the cyclist's helmet or the cyclist has heard the noise of the auto's engine as it is whizzing past.
Likewise, I propose to have the combination bicycle and parking lane parallel to, and to the right side of, the automobile lane, but with the traffic in the automobile lane proceeding in one direction and the bicycle traffic in the combination bicycle and parking lane proceeding in the opposite direction. In either daytime or nighttime with lights on, this gives both the auto driver and the cyclist a better opportunity to see that they are approaching each other. Also in nighttime with lights on, this gives the cyclist the opportunity to give a hand signal to the auto driver to lower the auto's headlights from high beam to low beam.
My proposed system for combining automobile traffic and bicycle traffic would apply to not only the development circles but also to the traffic circles, the entries, the exits and the arterial service roads and traffic circles outside the Bobstown Villages development ( FIG. 3 ).
I believe my proposed system for combining automobile traffic and bicycle traffic is preferable to our existing system, but if some jurisdictions insist upon the old rules of having automobiles and bicycles going the same direction, my new proposed road systems will remain unchanged. It is only necessary to reverse the painting of the arrows in the bicycle lanes to match the direction of the arrows in the parallel automobile lanes.
5. Reduction of Air Pollution
Air pollution is reduced because residents are almost required, by the design of the Bobstown Villages development ( FIG. 3 ), to walk or ride a bicycle rather than to drive an automobile. Who needs to drive an automobile if it is less than a quarter of a mile from the resident's home to the resident's office?
Examples of higher densities and mixed uses are set forth on the Bobstown Villages development ( FIG. 3 ), a 270-acre theoretical project. In this particular configuration, two modules of commercial (and residential) high-rise development are surrounded by twenty-eight modules of low-rise residential condominium development. The commercial development modules would consist of private or government offices, stores, theaters, high-rise residential condominiums, restaurants, parking garages, hospitals, schools, churches, etc. The most distant residents in the more affordable low-rise condominiums are less than one-quarter of a mile from the commercial area, and the residents of the more expensive high-rise condominiums are right in the middle of the commercial area.
The secret, of course, is to balance the jobs with the residences. For illustration purposes, I assumed there would be fourteen 15-story buildings, seven residential buildings and seven commercial buildings. This resulted in an estimated 1,260 dwelling units in the high-rise area. Four development circles in the two modules of high-rise development have been converted into larger parks. Ten traffic circles in the two modules of high-rise development have been converted into smaller parks. These fourteen parks in the center of the high-rise development modules are discussed further in paragraph 9 (Reduction in Inactivity and Obesity Problems).
To emphasize the problem that lower paid employees are least able to purchase homes, I allocated most of the 270-acres in the project to the more affordable low-rise residential condominiums. This resulted in an estimated 3,584 (28×128) dwelling units in the low-rise area, and a total of 4,844 (1,260+3,584) dwelling units (almost 18 dwelling units per acre) plus the job support services (1,785,000 square feet of office and commercial space) for the residents in the entire 270-acre project.
6. Reduction of Stream, River and Bay Pollution
Oil-based asphalt streets and storm drains required by governmental entities are probably the main causes of stream, river, bay and ocean pollution. So far the main prevention effort espoused by these governmental entities is to paint above the entry drains a sign like “DO NOT DUMP—FLOWS INTO THE BAY”. These signs are somewhat ironic because their implied meaning is that private individuals should not pollute, only governmental entities may pollute.
Neither private individuals nor governmental entities should pollute. Reduction of stream, river, bay and ocean pollution can be achieved in Circular Subdivisions by grading downward from the development circles into the larger and smaller parks and other planted areas and by using pervious concrete or pervious asphalt for sidewalks and roads similarly graded, thereby eliminating the need for storm drains in most geographic areas. The necessity for grading, or the angle of the grading, when necessary, will be determined by the porosity of the soils, and the amount and the intensity of the rainfall, in the particular area being developed.
7. Water Conservation
Particularly in the Western States of the United States, water conservation is a major political issue. In many jurisdictions landscaping is limited to drought-resistant native plants, usually resulting in prohibitions against planting grass in lawns or playgrounds. These prohibitions against planting grass are directly contrary to the solutions discussed in paragraph 9 (Reduction in Inactivity and Obesity Problems).
The Bobstown Villages development ( FIG. 3 ) resolves this conflict by providing for both water conservation and the reduction in inactivity and obesity problems. Fresh water will be used twice. There will be two distinct water distribution systems, one for potable water and another for non-potable water. The fresh potable water will be distributed to the various residential, office and commercial users, and then their effluents will be collected and treated by a waste-water treatment plant and the resulting non-potable water will be used to irrigate the landscaped areas, including the grass lawns and playgrounds.
8. Reduction in Global Warming
The principal contribution to a reduction in global warming will result from the lessening of reliance on automobiles and the substitution of walking and bicycle riding. Since there is a maximum distance of one-quarter mile from a resident's home to a resident's workplace, church, school, private or government offices, stores, theaters, restaurants, hospitals, etc., there is a minimal need for automobile travel.
A major contribution to a reduction in global warming will result from the substitution of pervious concrete or pervious asphalt for regular asphalt in all roads and sidewalks, and from the elimination of outdoor parking lots in the commercial development modules. Parking lots in the commercial development modules will be housed in certain of the high-rise buildings in the commercial development modules.
9. Reduction in Inactivity and Obesity Problems
There is no question that many adults and children in the United States have problems of inactivity and obesity. The worst example, however, appeared in the Nov. 24-26, 2006 weekend edition of the San Francisco Daily that reported:
“Not a single ninth grader tested in San Francisco's public schools could achieve adequate performance in all six categories of the state's physical fitness exam, according to the California Department of Education.”
In this city of almost 800,000 residents, this result is almost inconceivable.
The Bobstown Villages development ( FIG. 3 ) seeks to reduce inactivity and obesity problems of both adults and children. As previously explained in Paragraph 5 with respect to the two commercial modules in the center of the Bobstown Villages development ( FIG. 3 ), each of the four larger parks in the center is of sufficient size to accommodate such sports as soccer, lacrosse, field hockey, flag football, and in colder areas even ice-skating. Each of the ten smaller parks in the center will accommodate such activities as sand boxes for small children and their parents or teachers, volleyball, badminton, horseshoes, etc.
During school hours, all of the fourteen parks could be used primarily for the students of the schools and their parents or teachers. After 5:00 p.m., all of the fourteen parks could be used primarily for the tenants of the office buildings to engage in intramural sports. Today there is hardly a company that does not have employee T-shirts with the company's logo and products printed on the back. A company could compete in intramural sports with their competitors, perhaps more broadly defined to include the company's attorneys, accountants, insurance agents, suppliers, etc. After the intramural game is over it is quite likely that the employees and their “competitors” will go across the street for a light malt beverage and some pizza. Intramural sports, particularly co-ed intramural sports, are a great way for employees to meet other employees and their “competitors”.
I have intentionally omitted to provide for industrial land in the Bobstown Villages development ( FIG. 3 ). I realize that some of it is necessary, but it does not need to proliferate in every community. As a nation we are trending toward a work force of service people. If walkable communities such as I have proposed can have residents live, work, worship, learn, be entertained, etc. without having to drive their cars, we do not have to worry if a resident occasionally has to drive away several miles to purchase goods or services.
BEST MODE OF CARRYING OUT INVENTIONS
As stated in the application for the original Circular Subdivisions patent issued to me on Oct. 29, 2002, I did not intend to develop any CIRCULAR SUBDIVISIONS myself. The best mode then contemplated by me of carrying out my inventions was to enter into non-exclusive license agreements with both small and large capable professional residential, office, commercial and industrial developer-builders.
Unfortunately, before long I was advised that the National Association of Home Builders had concluded that the USPTO should not issue patents relating to land development or home building and had further adopted a policy against their member-builders entering into licensing agreements with United States patent holders having patents relating to land development or home building. Later I met in Washington, D.C. with the Manager, and one of his Assistants, of the Home Building Office of the U.S. Department of Housing and Urban Development. They both seemed very interested in the use of Circular Subdivisions as a means of providing affordable housing, and they scheduled another meeting with me a couple of days later to discuss the subject further. At this subsequent meeting they were very apologetic. They had discussed this matter with staff members at the National Association of Home Builders, had been advised about the Association's policy against patents relating to land development or home building, and had been warned that, if HUD became involved with Circular Subdivisions, the Association, or its member-builders, would discontinue their previous charitable activities of providing housing for low-income individuals.
I have neither the financial ability nor the life expectancy to attempt to upset the Association's policy against the USPTO issuing patents relating to land development or home building. If the legal department of the USPTO desires to do so, I would be willing to be a witness.
In view of the negative policy of the National Association of Home Builders, the best mode now contemplated by me of carrying out my inventions would be first to enter into non-exclusive license agreements with capable professional residential, office, commercial and industrial developer-builders that are not bound by the negative policy of the National Association of Home Builders, and (as a last resort) to attempt personally to develop an example of the Bobstown Villages walkable community subdivision covered by this Application (using qualified independent engineers, architects, contractors, etc. to perform the work).
DRAWINGS
FIG. 1 —Depicts Circular Subdivision detached single-family residences with the auto traffic in the automobile lanes and the bicycle traffic in the combination parking and bicycle lanes, each proceeding in opposite directions.
FIG. 2 —Depicts only the central row of the development circles on FIG. 1 , making the traffic arrows easier to read.
FIG. 3 —Depicts an entire walkable community, Bobstown Villages, for about 20,000 residents, all of whom are only a short walk (no more than one-quarter mile) from their private or government offices, stores, theaters, high-rise residential condominiums, restaurants, parking garages, hospitals, schools, churches, etc., in the center of the community.
FIG. 4 —Depicts a typical Circular Subdivision two-story residential condominium area with one large park and four smaller parks in the center. These represent the twenty-eight low-rise residential areas in the Bobstown Villages development ( FIG. 3 ) that surround the high-rise downtown area in the center of the community. | A walkable community subdivision is provided with a plurality of traffic circles. Each traffic circle can contain one or more playgrounds or parks. A plurality of development circles containing one or more buildings or playgrounds. The outer circles of the subdivision are graded toward a center of the community such that storm water run-off is directed to a center circle, which has a storm water storage capacity. Thus eliminating the use of storm water drainage pipes in the community. | 4 |
BACKGROUND OF THE INVENTION
The invention relates to an air conditioning apparatus, and more particularly to an air conditioning apparatus which has an absorption type heat pump functioning as an essential part thereof.
There are known some absorption type heat pumps in which lithium bromide is used as an absorbent dissolved in a coolant, the coolant being water. Such known heat pumps could not be employed in air conditioning apparatuses in order for air heating during cold seasons when a running temperature within an evaporator fell to some degrees below 0° C. and the coolant water froze therein due to low outdoor temperature.
Therefore, it has been proposed to utilize pure methanol as the coolant so as to solve the abovedescribed problem. The evaporation heat of methanol is however comparatively less than that of water so that refrigerating capacity of such apparatus is unavoidably reduced to some extent thereby resulting in a scale-up of said apparatus.
SUMMARY OF THE INVENTION
The invention aims at solution of the aforementioned problems.
A primary object of the invention is therefore to provide an air conditioning apparatus having an absorption type heat pump incorporated therein and adapted for air heating even at a lower outdoor temperature and an evaporator temperature below 0° C.
Another object of the invention is to provide an air conditioning apparatus having an absorption type heat pump comprising an evaporator for evaporation of a coolant, an absorber containing a solution of an absorbent dissolved in the coolant, the solution absorbing coolant vapor flowing into the absorber from the evaporator, a regenerator for boiling and concentrating the absorbent soluton diluted in the absorber, and a condenser adapted to condense coolant vapor flowing thereinto from the regenerator wherein the absorbent solution is recirculated into the absorber after condensed by said regenerator, characterized in that the absorbent is a mixture of lithium bromide and zinc chloride and that the coolant is a mixed solvent composed of water and methanol.
In a preferred embodiment of the invention, the mixed solvent has a ratio by weight of methanol to water, the ratio falling in a range between about 0.1 and about 0.3, said ratio being that measured on the absorbent solution in the evaporator.
According to the invention, a temperature within the evaporator can be set at some degrees below 0° C. even when the outdoor temperature is remarkably low. This is an effect of the compositions of the absorbent and the coolant, i.e. said absorbent mixture of lithium bromide and zinc chloride and said coolant mixture of water and methanol. The heat pump in the invention can now be operated for air heating at such a low outdoor temperature that the known coolant, i.e. water, would otherwise freeze in known apparatuses. Besides, an air cooling capacity of the heat pump is not affected very much but maintained at a sufficiently high level by the abovedescribed compositions of the absorbent and the coolant. Furthermore, a temperature within the absorber can also be set, without any crystallization problem, at a higher temperature than in a known system utilizing only lithium bromide as the absorbent. Said higher temperature of the absorber affords a higher temperature in air heating.
Other objects and advantages will become clear in the following description of an embodiment by referring to the drawings, in which:
FIG. 1 is a schematic illustration of an absorption type heat pump utilized as an essential part of an air cooling and heating apparatus; and
FIG. 2 is a diagram showing an operation condition in an embodiment of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The general principle in operation of an absorption type heat pump will be explained at first prior to description of the embodiment.
As shown in FIG. 1, the heat pump 1 is in operation for air heating and comprises a regenerator 2 to which fuel of a kind such as town gas is supplied through a pipe 4. Combustion heat of the fuel gas is a heat source for driving the heat pump. The heat causes a coolant to evaporate within said regenerator 2. Vapor of the coolant is introduced into a condenser 5 so as to condense therein giving an amount of condensation heat to cooling water flowing through a coiled tube 6. The coolant thus liquefied will then be delivered to an evaporator 7 which is kept at a pressure lower than that in the condenser. The coolant evaporates under this pressure thereby taking an amount of evaporation heat from water which is flowing through another coiled tube 8. The water thus cooled in said tube 8 is then subjected to a heat exchange process between atmosphere and cold water by means of an outdoor unit, or may be utilized for air cooling. On the other hand, vapor of the coolant flows from the evaporator 7 into an absorber 9 so as to be absorbed therein by an absorbent solution which has been concentrated in the regenerator 2 and is flowing into said absorber through a pipe 3. A considerable amount of absorption heat will be liberated and given to water which is flowing through a further coiled tube 11. The heated water within said tube 11 is subjected to a further heat exchange process between the room air and said heated water by means of an indoor unit not shown. Air heating is thus effected by the indoor unit. The condensation heat liberated in the condenser 5 can also be made use of for air heating. The absorbent solution which has absorbed the coolant vapor flows then into the aforementioned regenerator 2 via a heat exchanger 10. This cycle will be continued for air heating.
In case of air cooling, an amount of heat of room air is taken up by the evaporator 7 while the absorption heat generating in the absorber 9 thereby being radiated into outdoor atmosphere together with the condensation heat generating in the condenser.
When the atmosphere temperature is only at some degrees above 0° C., temperature of the evaporator 7 should be set at some degrees below 0° C. The coolant, i.e. water, inevitably freezes in the evaporator in such a condition thereby making it impossible to operate the pump, if lithium bromide is used as the absorbent and water is the coolant as is in the known air cooling and heating systems which utilize the absorption type heat pump.
The invention will now be described below in detail.
A novel air cooling and heating apparatus according to the invention comprises an improved heat pump of absorption type in which a coolant is composed of methanol dissolved in water and a mixture of lithium bromide and zonc chloride is used as an absorbent. Freezing point of the coolant descends to a certain degree by dissolving methanol into water whereby the coolant can be prevented from freezing even at some degrees below 0° C. The mixing of methanol into water has proved to be of no bad influence on the system from a practical point of view. When a weight ratio CI of methanol to water is 0.1, 0.2 or 0.3, the freezing point of the coolant is -5.7° C., -14.5° C. or -25.9° C., respectively. Accordingly, the evaporator temperature can be set at about -5° C. to -25° C. if the coolant contains methanol at the weight ratio CI of about 0.1 to 0.3, the ratio being measured on the absorbent solution in the evaporator. It is possible with such a coolant to effectively operate the heat pump even when the outdoor temperature is considerably low in winter. Contrary to this, the coolant would have a freezing point above -6° C. when its CI value were smaller than 0.1, this resulting in a possible evaporator temperature higher than -6° C. which cannot permit the heat pump to be operated at a considerably low outdoor temperature. Though the freezing point of the coolant becomes lower than -26° C. with its CI value greater than 0.3, it would be scarcely necessary to adopt such a low evaporator temperature in most countries of the temperate zone and the subarctic zone.
On the other hand, a mixture of lithium bromide and zinc chloride is employed as the absorbent in the invention so that crystallization temperature at which the absorbent begins to crystallize is lower than that in case of using lithium bromide only. This lower crystallization temperature makes it possible to increase a concentration of the absorbent and consequently to raise the temperatures within the absorber and of air heating. The lowest crystallization temperature will be obtained when a weight ratio CII of zinc chloride to lithium bromide is 1, thus providing a possibility to employ the highest absorber temperature. If the value CII is smaller than 0.8 or greater than 1.2, the extent to which the crystallization temperature descends would be not sufficient for a desired high temperature in the absorber.
FIG. 2 is a diagram illustrating an operation condition of the apparatus in the invention. In this embodiment the value CII of the absorbent is set at 1 with the value CI of the coolant set at 0.1. The temperatures T° C. of said absorbent solution and coolant are indicated on the transversal axis of abscissa of the diagram whereas the pressures P mmHg thereof are indicated on the vertical axis of abscissa. The line 12 shows a vapor pressure curve of the coolant, i.e. mixture of methanol and water.
For example, the temperature T 2 shall be set at 53° C. for the condenser 5 and an outlet of the absorber 9 in accordance with a given temperature which is to be maintained in a room or rooms by air heating. The pressures P 2 within the condenser 5 and the regenerator 2 are thus 156 mmHg as read form the line 12. If the temperature within the evaporator 7 is set at for example -2° C. which is lower than the outdoor temperature and has been impossible in the known apparatuses, the pressures P 1 within the evaporator 7 and the absorber 9 will be 7 mmHg as read also from the line 12. It is supposed that the temperature T 3 at an inlet of the absorber 9 is set at for instance 58° C. at which the absorbent does not crystallize.
A circulation cycle of the absorbent solution is illustrated by a loop line passing through points A, B, C, and D wherein a line AB shows a concentration process effected between an inlet into and an outlet from the regenerator 2. Another line CD shows an absorption process effected within the absorber 9 to absorb the coolant vapor into the absorbent solution. A point E indicates a state of the coolant during a condensation process effected in the condenser 5 whereas another point F indicates a state of the coolant during a vaporization process effected in the evaporator 7. A concentration of the absorbent in said absorbent solution measured on the points D and A can be estimated to be 77% by means of the temperature T 2 at the outlet of the absorber 9 and the pressure P 1 within said absorber 9. Another concentration of the absorbent on the points B and C will be 80% as similarly estimated from the temperature T 3 at the inlet of said absorber 9 and the pressure P 1 . A temperature T 4 at the outlet of the regenerator 2 can be estimated to be 135° C. from the pressure P 2 and the concentration 80%.
Another cycle AEFD in FIG. 2 represents a thermodynamic change in state of the coolant wherein a line AE shows the vaporization in the regenerator and another line FD shows the absorption in the absorber.
It will be now understood that the heat pump in the invention can be successfully operated, as is in the above example, even if the evaporator temperature T 1 is set at two degrees below 0° C. which temperature has been impossible to be adopted in the known apparatuses. Such an air heating operation is effected with the outlet temperature T 2 of the absorber at 53° C. Moreover, the temperatures T 2 and T 3 of said absorber 9 can be maintained sufficiently high for air heating and without a problem of crystallization because the exemplified absorbent is the mixture composed of lithium bromide and zinc chloride with the same parts by weight thereof (i.e. CII=1).
Although the above embodiment is described as to the first kind or class of heat pump, the invention can be embodied not only into a second kind or class of absorption type heat pump but also into a heat pump of multistage absorption type.
Furthermore, the invention can be applied also to an air cooling apparatus or to an air heating and/or cooling apparatus adapted to supply hot water. | The air conditioning apparatus according to the invention comprises an absorption type heat pump comprising a system including an absorber, a regenerator, a condenser and an evaporator. A mixture of lithium bromide and zinc chloride is used as an absorbent which is dissolved to form an absorbent solution into a mixed solvent having a ratio by weight of methanol to water, the ratio falling in a range between 0.1 and 0.3. Said solution is circulated through the system. | 8 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to pattern and buttonhole control systems for a sewing machine.
2. Description of the Prior Art
Pattern and buttonhole control systems in a sewing machine generally include needle positioning mechanism capable of discriminating between pattern and buttonhole control signals, and of transmitting either through common mechanism to a movable needle bar. The present invention is directed to needle positioning mechanism as described in association with locking mechanism which is selectively operable to positively condition the needle positioning mechanism to transmit either pattern or buttonhole control signals, and thereby prevent the transmission of improper signals to a needle bar.
SUMMARY OF THE INVENTION
Mechanism in accordance with the invention for controlling needle bight in a sewing machine includes a bell crank with an input arm, an output arm, a needle bar actuating link operably connected to the output arm, and a carrier for the bell crank. The bell crank is mounted for pivotal movement about an axis on the carrier, and the carrier is mounted for movement about a different axis affixed on the machine. Means are provided for locking the carrier in a fixed position in the machine to prevent pivotal movement about said fixed axis, and for unlocking the carrier to permit the said pivotal movement thereof. Bight controlling movements for pattern sewing are imparted to the input arm of the bell crank, when the carrier is locked, to thereby cause the bell crank to pivot on the carrier and move the needle bar actuating link. Bight controlling movements for buttonhole sewing are imparted to the input arm of the bell crank and the carrier while the carrier is unlocked to cause the bell crank and carrier to pivot on their respective axes and influence movement of the needle bar link.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view showing a pattern and buttonhole control arrangement including mechanism according to the invention;
FIGS. 2 and 3 are enlarged fragmentary views showing a portion of the control of FIG. 1;
FIG. 4 is another enlarged fragmentary view showing a portion of the control of FIG. 1; and,
FIG. 5 is an exploaded perspective view of of a portion of the control of FIG. 1.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to the drawings, reference character 10 designates a sewing machine pushbutton control module which is generally of the kind shown in U.S. Pat. No. 4,441,440 for "Push-Button Control Module for a Sewing Machine". The module, which is to be understood as being affixed in a machine 11, includes sewing mode selecting pushbuttons A and B for straight and zig-zag stitching, respectively, pushbuttons C through P for pattern sewing, and pushbuttons X and Y for buttonhole sewing. The mode includes a stack 12 of rotatable cams and a stack 14 of pivotally mounted cam followers. The cams are rotatable by a shaft 15 which is driven by a gear 16 during operation of the machine. Each of the cam followers can be selectively positioned by operation of the pushbuttons into engagement at one end with an associated cam of the cam stack, and at the other end with a needle plate 18, feed wobble plate 20 or crank 22. A shaft 24 affixed in a top plate 26 and bottom plate 28 of the module defines a common axis about which needle plate 18, feed wobble plate 20 and crank 22 may be pivoted by the cam followers.
Needle plate 18 terminates at its upper end in a bracket 30 which includes a circularly extending arcuate slot 32. One end of link 34 carries a pin 36 which extends into slot 32, and the opposite end is pivotally connected by a pin 38, at a center defining the arcuate outline of slot 32, to one arm 40 of the bell crank 42. The other arm 44 of the bell crank is pivotally connected at 46 to a needle bar actuating link 48. Bell crank 42 is pivotally mounted between arms 40 and 44 on a stub shaft 50 affixed in a carrier 52. The carrier is pivotally supported on a pin 54 which is located in top plate 26 of module 10 to establish a fixed pivotal axis for the carrier. A pin 56 in an arm 58 of carrier 52 connects the carrier with crank 22 at a slot 59 therein. Another arm 60 of the carrier includes a curved end portion 62 with a terminal slot 64. A latch 66 pivotally mounted on plate 26 at 68 includes an end key 70 engageable at slot 64 with carrier arm 60 for locking the carrier in a fixed position on plate 26 and disengageable from said arm for unlocking the carrier to enable movement of the carrier about its pivotal axis. Latch 66 is normally disposed by a spring 71 with key 70 in slot 64 to lock the carrier 52 in a fixed position on plate 26. The carrier is unlocked by the depression of button X or Y.
Pin 36 is positionable in slot 32 on needle plate 18 with a lever 72 acting through links 74 and 76, and for any particular position of pin 36 in slot 32, the pin is rocked by needle plate 18 about the axis of shaft 24 in response to pivotal movement of plate 18 as determined by a selected follower and actuating cam. Movement of the pin 36 is transmitted through link 34 to bell crank 42 which is thereby caused to pivot on stub shaft 50 and move needle bar actuating link 48 accordingly. As will be made apparent hereinafter, movement of crank 22 by a cam follower can occur only while carrier 52 is unlocked. Movement may then be imparted to the carrier about its pivotal axis by crank 22, and to the pivotal axis of bell crank 42 by the carrier. As the pivotal axis of the bell crank 42 is moved needle bar actuating link 48 which is pivoted on arm 40 of the bell crank is moved accordingly.
As shown, needle bar actuating link 48 connects through an adjustable extension 78 with a needle bar post 80. A gate 82 and needle bar 84 are laterally movable in a manner well known by the post 80 as a needle 86 is reciprocated endwise by driving mechanism 85 which is operably connected to the needle bar.
Any pushbutton of module 10 may be depressed into a position wherein it is held against the outward bias of an associated spring 88 by a latch 90, and when so depressed any button previously moved into a latched position is released and returned by its spring to a normal unactuated position, all as described in U.S. Pat. No. 4,441,440 mentioned hereinbefore. Assuming a pushbutton for pattern sewing, such as pushbutton C, is moved into a latched position (see FIG. 2), an associated cam follower 14 c is caused to ride up along an edge of an extension 92 of the pushbutton and move on pin 94 into an activated position of enforced engagement of one end 96 c with an associated cam 12 c and at the opposite end 98 c with needle plate 18. During the rotation of shaft 15 by gear 16, the follower is rocked, in a manner predetermined by the profile of the cam, about the pushbutton extension 92 serving as a supporting fulcrum. The follower positions and imparts pivotal movement to needle plate 18 and the needle plate acting through bracket 30, pin 36, link 34, bell crank 42, needle bar actuating link 48, needle bar post 80 and gate 82 controls the positioning and side to side movement of needle bar 84. The carrier 52 is locked in a fixed position on plate 26 at such time and does not influence the motion of the needle bar.
When a pushbutton for initiating buttonhole sewing such as pushbutton X is depressed to a latched position (see FIG. 3) an extension 104 moves an associated cam follower 14 x into a supported position thereon, and into forced engagement at opposite ends 96 x and 98 x with a buttonhole cam 12 x and one end 106 of crank 22, respectively. At the same time, a floating extension 108 is caused by button X to move two other cam followers 14 F1 and 14 F2 into supported positions thereon, and into enforced engagement at ends 96 F1 and 96 F2 with associated buttonhole cams 12 F1 and 12 F2 , and at opposite ends 98 F1 and 98 F2 with a finger like projecting portion 109 of feed wobble plate 20 and with needle plate 18, respectively. Floating extensions 108 is also caused by the depression of button X to act against an arm 110 on latch 66 and move the latch 66 against the bias of spring 71 as required to unlock carrier 52.
As cam shaft 15 is rotated, crank 22, needle plate 18 and feed wobble plate 20 are moved by the engaging followers in accordance with the profiles of the buttonhole cams. The buttonhole cams are of a well known type used in buttonhole sewing, the buttonhole cam in engagement with the crank associated follower being a needle positioning and barring cam, the buttonhole cam in engagement with the feed wobble plate associated follower being a feed direction controlling cam, and the other buttonhole cam being a needle zig-zag cam. Clutching and tripping control means (not shown) of a kind such as disclosed in U.S. Pat. No. 3,841,246 of John W. Casner et al issued Oct. 15, 1974, drivably connect and disconnect the needle positioning and barring cam to and from drive shaft 15 during the sewing of a buttonhole as required to effect the formation of a buttonhole of predetermined lengths.
As crank 22 is moved by the engaging follower, carrier 52 is pivoted by the crank acting thereon through pin 56 and moves the pivotal axis of bell crank 42 to influence of needle bar 84 to which the bell crank is connected through needle bar actuating link 48, needle bar post 80 and gate 82. Needle plate 18 acting through bracket 30, pin 36, and link 34 pivotes the bell crank on stub shaft 50 and thereby also influences movement of the needle bar. Feed wobble plate 20 acting through extension 111, finger 112, bracket 114 and arm 116 positions feed regulating mechanism (not shown) suitably connected to arm 116 to provide for the feeding of material in a forward and reverse direction during the formation of a buttonhole. Such feed regulating mechanism may be of the kind shown, for example, in U.S. Pat. No. 3,527,183 for "Work Feeding Mechanism for Sewing Machine" of Jan Szostak, issued Sept. 8, 1970.
It is to be understood that the present disclosure relates to a preferred embodiment of the invention which is for purposes of illustration only and is not to be construed as limiting the invention. Numerouse alterations and modifications of the structure herein will suggest themselves to those skilled in the art, and all such modifications which do not depart from the spirit and scope of the invention are intended to be included within the scope of the appended claims. | A pushbutton control for a sewing machine is provided with a pivotably mounted carrier for a bell crank which is operably connected to a needle bar. Bight controlling movements are imparted to the needle bar according to the actuation of the bell crank and carrier. | 3 |
This application is a division of application Ser. No. 08/384,079 filed Feb. 6, 1995, now abandoned, which is a continuation-in-part of application Ser. No. 08/105,430, filed Aug. 10, 1993 abandoned, which is a continuation-in-part of application Ser. No. 07/962,416, filed Oct. 16, 1992 abandoned, which is a continuation-in-part of application Ser. No. 07/779,014 filed Oct. 18, 1991 abandoned.
TECHNICAL FIELD
This invention relates to a method for preventing transmissions of viral pathogens using a microporous membrane which is breathable, liquid repellent, and a viral barrier. The membrane or membrane laminated to a fabric can be used as a surgical gown, drape, mask, gloves, sterile wraps, wound dressings, waste disposal bag or other products requiring viral barrier properties combined with breathability.
BACKGROUND OF THE INVENTION
Surgical gowns, drapes and the like protect surgically prepared areas of the skin from contamination and also protect surgeons and nurses against contamination through contact with unprepared or contaminated areas of patient's skin. In addition, surgical gowns and drapes should present a sterile barrier to protect patients from contamination through contact with the surgeon.
Liquid repellency of the gown or drape is recognized as an important property in assuring that the gown or drape protects and acts as a barrier to the passage of bacteria or viruses carried in liquids. Body liquids and other liquids can permeate through the surgical gown or drape lacking liquid repellency properties. Thus, bacteria and viruses, such as the human immunodeficiency virus and hepatitis B virus, which may be present on the surface of the gown or drape can be transported through the gown to the patient or the operating room personnel.
In addition to being liquid repellent and a bacteria and viral barrier, hospital gowns and drapes desirably present a non-glare outer surface, are nonlinting, possess antistatic characteristics, and, not least importantly, are comfortable to wear.
It has been widely recognized that garments must be "breathable" to be comfortable. While it is not necessary, although preferable, that air pass through the garment for it to be comfortable, it is essential that water vapor from perspiration be transmitted from inside to outside so that a natural evaporative cooling effect can be achieved. If a continuous film of hydrophilic material is exposed to air containing a high concentration of water vapor on one side of the film, and to air containing a lower concentration of water vapor on the other side, the side of the film exposed to the higher water vapor concentration will absorb water molecules which diffuse through the film and are desorbed or evaporated on the side exposed to the lower water vapor concentration. Thus, in a continuous film of hydrophilic material, water vapor is effectively transported through the film on a molecule by molecule basis. This property is known as moisture vapor transmission. Generally, in microporous films water vapor is also transported by the diffusion of water vapor in the air which is able to permeate the membrane.
One type of commonly used protective clothing is made from nonwoven substrate calendared at high temperature and pressure. While having reasonable properties for protection, garments constructed of this material are known to be very uncomfortable due to their inherent low moisture vapor transmission and low air permeability characteristics, i.e., their low breathability. Various attempts have been made to improve breathability of this nonwoven material. These efforts, however, frequently result in a more open structure of the nonwoven material and thus also simultaneously lower its protection value. Coatings on polyolefin nonwovens have been employed to afford greater barrier protection to the `open` base structure of the nonwoven. However, the already inherently low moisture transmission and air permeability characteristics of the nonwoven material are even further reduced, simultaneously reducing the comfort of garments made by use of this technology.
Protective clothing in hospital operating rooms has been made of spun-laced nonwovens of polyester and wood pulp fibers, heavily treated with a water-repellent. Here, again, a compromise in properties must be reached. Greater comfort sacrifices maximum microorganism barrier protection and greater barrier protection lowers comfort. For instance, where hospital operating room gown products require superior protection from microorganisms, a dense, nonporous polyethylene film is usually laminated to the nonwoven. But, while achieving good barrier characteristics, moisture vapor transmission is substantially eliminated.
As seen from the foregoing, protection properties and comfort properties are traded off with one another. The present invention allows for both desirably good barrier protection characteristics while simultaneously achieving excellent moisture vapor transmitting characteristics, i.e. providing both protection and comfort.
U.S. Pat. No. 4,961,985 (Henn et al.) describes a coated product for use as a fabric for protective clothing. The product is made of a substrate and a coating comprised of a microporous scaffold material having a high void volume and open, interconnecting void microstructure, at least partially filled with a layer of a selected polyurethane. The product has viral barrier properties.
U.S. Pat. No. 5,017,292 (DiLeo et al.) describes a particular asymmetric composite membrane structure having skin possessing ultrafiltration separation properties, a porous substrate and a porous intermediate zone that is particularly useful for selectively isolating virus from a protein-containing solution.
Japanese Laid-Open (Kokai) Patent Application S.60-142860 (Kawase et al.) describes a method of removing viruses in water or a water solution by filtering through a porous polyolefin membrane having micropores with an average diameter of 0.05-0.30 mm, a pore rate of 30-90 (v/v) %, a thickness of 5-100 mm and air filtration velocity of 5-30×10 4 l/m 2 hr 0.5 atm at a between-membrane pressure difference of less than 2 kg/cm 2 .
Japanese Laid-Open (Kokai) Patent Application H. 1-305001 (Mitsutani) describes a method of preserving bulbs using a material which allows oxygen to pass through but prevents viruses from reaching the bulbs. The material is a film described as a porous, hydrophilic polyolefin, polyvinyl alcohol, cellulose acetate, regenerated cellulose, polypropylene, polyethylene, polyethylene copolymer, cellulose mixed ester resin and fluoride resin. The material may also be a solution that can be coated onto the bulb. This material should be water soluble, allow oxygen to pass through, but stop viruses. Examples of this material are cellulose acetate phthalate, methyl methacrylate methacrylic acid, polymer synthetic products, cellulose, and natural products.
Japanese Laid-Open (Kokai) Patent Application H2-212527 (Matsumoto) describes a method for making a porous filtration membrane by exposing a film to high energy particles, chemically etching the film to make uniform pore diameters, and graft polymerizing a hydrophilic monomer such as acrylic acid onto the porous film. The polymer for the film is selected from polyethylene, polypropylene, ethylene-alpha-olefin copolymer such as ethylene-propylene copolymer and polyvinylidene fluoride. The porous membrane described in this application can be used in the water system for separation of bacteria and viruses.
Japanese Laid-Open (Kokai) Patent Application S.64-22305 (Shiro) describes porous polypropylene fibers and the pathogenic agent filtering apparatus using these fibers. The apparatus can remove pathogenic agents (bacteria and viruses) contained in the serum from the blood of germ carriers. The hollow fiber is formed by special drawing and stretching conditions. The hollow fiber is characterized in that the pore shape is extremely uniform and the pore diameter distribution is narrow. The pore diameter is on the average of 50-250 nanometers.
U.S. Pat. No. 4,194,041 (Gore et al.) is representative of a number of patents which describe coatings or laminates purported to provide waterproof articles which do not leak when touched and are breathable. This patent describes a layered article for use in waterproof garments or tents comprising at least two layers: an interior, continuous hydrophilic layer that readily allows water vapor to diffuse therethrough, prevents the transport of surface active agents and contaminating substances such as those found in perspiration, and is substantially resistant to pressure induced flow of liquid water, and a hydrophobic layer that permits the transmission of water vapor and provides thermal insulating properties even when exposed to rain. The hydrophobic layer is preferably waterproof microporous tetrafluoroethylene (PTFE) or polypropylene, which permits the passage of moisture vapor through the pores thereof. The hydrophilic layer transfers moisture vapor therethrough whereupon it passes through the porous hydrophobic layer. Various means of joining the layers are suggested including the application of hydraulic pressure to force the hydrophilic polymer to penetrate into the surface void spaces of the hydrophobic layer.
U.S. Pat. No. 4,443,511 (Worden et al.) discloses a layered waterproof, breathable and stretchable article for use in, for example, material for protective articles. Also disclosed is a waterproof and breathable elastomeric polytetrafluoroethylene layered article bonded to a stretch fabric. The water proof and breathable elastomeric polytetrafluoroethylene layered article bonded to a stretch fabric is described as durable and possessing a moisture vapor transmission rate exceeding 1000 gms/m 2 day.
U.S. Pat. No. 4,613,544 (Burleigh) describes a waterproof, moisture vapor permeable unitary sheet material comprising a microporous polymeric matrix having pores comprising continuous passages extending through its thickness and opening into the opposite surfaces thereof, the passages being sufficiently filled with a moisture vapor permeable, water impermeable, hydrophilic material to prevent the passage of water and other liquids through the unitary sheet material while readily permitting moisture vapor transmission therethrough rendering the sheet material breathable. The unitary sheet is made by causing a liquid composition comprising the hydrophilic material or precursor thereof to flow into the pores of the matrix, then causing the conversion thereof to solid hydrophilic material.
While these materials alleviate some of the problems known to the art, many require lamination to protect the water repellent, moisture vapor permeable material they use in their constructions while others require void filling which can lower the moisture vapor transmission rate of the material and decrease its ability to heat seal. Joining of multiple pieces of these materials in a three dimensional garment presents additional problems in that most of these materials are not readily joined together by any means other than sewing which creates needle holes that must be subsequently sealed with seaming tapes or alternative filling techniques to provide a totally waterproof garment. Also, due to the dense nature of the hydrophilic layer, many of these materials are minimally permeable to air.
U.S. Pat. No. 5,025,052 (Crater et al.) describes fluorochemical oxazolidinone compositions and their use for oil and water repellency in films, fibers, and non-woven webs.
U.S. Pat. No. 4,539,256 (Shipman) discloses a microporous sheet material formed by liquid-solid phase separation of a crystallizable thermoplastic polymer with a compound which is miscible with the thermoplastic polymer at the melting temperature of the polymer but phase separates on cooling at or below the crystallization temperature of the polymer.
U.S. Pat. No. 4,726,989 (Mrozinski) discloses a microporous material similar to that of Shipman but which also incorporates a nucleating agent.
U.S. Pat. No. 4,867,881 (Kinzer) discloses an oriented microporous film formed by liquid-liquid phase separation of a crystalline thermoplastic polymer and a compatible liquid.
The present invention relates to a method of preventing transmission of viral pathogens between a source of viral pathogens and a target of said viral pathogens comprising positioning between said source and said target a microporous membrane material comprising (1) a thermoplastic polymer or polytetrafluoroethylene and (2) a water- and oil-repellent fluorochemical compound which provides said membrane with oleophobic, hydrophobic and viral barrier properties. The fluorochemical compound can be introduced as a melt additive during the membrane preparation or as a topical treatment after the membrane is made. The membrane material is moisture vapor, air permeable and sweat contamination resistant. The membrane material is also heat sealable when made using a thermoplastic polymer.
In a preferred embodiment, the membrane comprises (1) a crystallized olefin polymer, and, disposed within the pores a processing compound which is miscible with the olefin polymer at the melting point of the polymer but phase separates on cooling to or below the crystallization temperature of the polymer and (2) a fluorochemical oxazolidinone compound, a fluorochemical aminoalcohol compound, an amorphous fluoropolymer, a fluoroacrylate polymer, a fluorochemical piperazine, a fluorochemical acrylic ester or a blend thereof.
In another preferred embodiment of the invention, the microporous membrane comprises (1) a polyolefin resin or a blend of polyolefin resins (2) finely divided inorganic filler material having a melting point above the polyolefin degradation temperature(s) and (3) a fluorochemical compound which provides the membrane with viral barrier properties, the membrane being oriented in at least one direction. Generally, the fluorochemical compound is a water- and oil-repellent fluorochemical compound. Preferred fluorochemical compounds include fluorochemical oxazolidinones, fluorochemical aminoalcohols, amorphous fluoropolymers, fluoroacrylate polymers, fluorochemical piperazines, fluorochemical stearates and blends thereof.
The present invention further provides a microporous membrane material and articles such as surgical gowns, drapes, masks, gloves, sterile wraps, wound dressings and waste disposal bags for containment of virally contaminated materials, comprising (1) a thermoplastic polymer or polytetrafluoroethylene and (2) a water- and oil-repellent fluorochemical compound which provides said membrane with oleophobic, hydrophobic and viral barrier properties. The articles may be disposable or reusable.
The microporous membrane materials useful in the present invention retain their viral barrier, liquid repellency and moisture vapor and air permeability properties for extended periods even in garment and surgical drape applications which expose the membrane materials to perspiration residues which are known to contaminate and ultimately destroy repellency properties of conventional liquid repellent, moisture vapor permeable materials. Surprisingly, the materials useful in the invention prepared by incorporating the fluorochemical compound as a melt additive retain this contamination resistance to perspiration despite the presence of the processing compound, an oleophilic material. Further, the microporous membrane materials useful in the invention repel mineral oil even when they contain mineral oil. The microporous membrane materials useful in the present invention also possess excellent hand and drape properties.
DETAILED DESCRIPTION
The viral barrier, liquid repellent, moisture vapor and air permeable, microporous membrane materials useful in the present invention repel aqueous based fluids as well as a variety of other liquids, such as perspiration which contains oil-based components, and prevent penetration of the liquids through the thin (5 to 250 microns) membrane, even when the liquid is propelled against the membrane material. The microporous membrane materials, while water repellent, also have very high moisture vapor permeabilities coupled with significant air permeability properties.
Garments fabricated from the microporous membrane materials useful in the present invention allow for the transfer of moisture vapor resulting from perspiration through the garment at a rate sufficient to maintain the skin of the wearer in a reasonably dry state under normal use conditions. The microporous membrane materials useful in the present invention differ from prior art single layer microporous liquid repellent, moisture vapor permeable materials in that they are not subject to contamination by perspiration residues which reduce and ultimately destroy the repellency properties of the material. This difference allows the membrane materials useful in the present invention to be used in garment applications without a protective overlayer.
The microporous membrane materials useful in the present invention exhibit durability of their liquid repellency properties when subjected to sterilization, rubbing, touching, folding, flexing or abrasive contacts. The microporous membrane materials useful in the present invention also display oleophobic properties, resisting penetration by oils and greases and they are heat sealable when thermoplastic. The oleophobicity and heat sealing properties of the membrane materials prepared by phase separation are most surprising in that the membrane materials contain an oily, oleophilic processing compound which, a priori, one would expect, would promote wetting by other oleophilic materials and which also would inhibit heat sealing.
Transport of a liquid challenge through most porous materials or fabrics occurs because the liquid is able to wet the material. The likely route through the material is for the liquid to initially wet the surface of the material and to subsequently enter the pore openings at the surface of the material followed by a progressive wetting of and travel through the interconnected pores until finally reaching the opposite surface of the material. If the liquid has difficulty wetting the material, liquid penetration into and through the material will, for the most, be reduced. The similar phenomena occurs in the pores, where reduced wetability, in turn, reduces pore invasion. The greater the numerical difference between the liquid surface tension of the liquid and the surface energy of the porous material (the latter being lower), the less likely the liquid will wet the porous material.
The addition of a fluorochemical to the microporous membrane useful in the present invention reduces the surface energy of the membrane, thereby increasing the numerical difference between its surface energy and the surface tension of challenge liquids. A preferred class of fluorochemicals is fluorochemical oxazolidinone compounds which are normally solid at room temperature, water-insoluble, fluoroaliphatic radical-containing 2-oxazolidinone compounds which have one or more 2-oxazolidinone moieties, at least one of which has a monovalent fluoroaliphatic radical containing at least 3 fully fluorinated terminal carbon atoms bonded to the 5-position carbon atom thereof by an organic linking group. Particularly preferred is a fluorochemical oxazolidinone represented by the formula ##STR1##
Such oxazolidinones are described, for example, in U.S. Pat. No. 5,025,052 (Crater et al.) which is incorporated herein by reference.
Another preferred class of fluorochemical compounds is fluorochemical aminoalcohol compounds. Such fluorochemical aminoalcohol compounds are disclosed, for example, in U.S. Pat. No. 3,870,748 (Katsushima et al.), U.S. Pat. No. 4,084,059 (Katsushima et al.) which are incorporated by reference herein and Plenkiewicz et al., "Synthetic Utility of 3-(Perfluoro-1,1-Dimethyl-1-Propene. Part II. Synthesis of New 2-Hydroxy-3-(Perfluoro-alkyl)Propyl-Amines", Journal of Fluorine Chemistry vol. 45, pp 389-400 (1989).
Additional preferred fluorochemical compounds useful for topical treatment of the microporous membrane include amorphous fluoropolymers available under the tradename TEFLON from DuPont Polymer Products, fluoroacrylate polymers which can be formed from fluoroacrylate monomers available under the tradename ZONYL from DuPont Polymer Products, fluorochemical carboxylic acid esters such as those disclosed in U.S. Pat. No. 3,923,715 (Dettre et al.) and fluorochemical acrylic copolymers such as those described in U.S. Pat. No. 3,341,497, and fluorochemical piperazines which can be prepared by reacting fluoroaliphatic radical-containing piperazine compounds such as described in Katritzky et al., "Design and Synthesis of Novel Fluorinated Surfactants for Hydrocarbon Subphases," Langmuir, vol. 4, no. 3, pp. 732-735 (1988) with, e.g., aliphatic and aromatic epoxides, halides and isocyanates.
It is also expected that additional oil and water repellent fluorochemical compositions would also provide viral barrier properties when added during extrusion at the proper extrusion conditions or when topically applied. Preferably, the fluorochemical composition is soluble in the polymer or processing compound in the molten state.
The oleophobic, hydrophobic, moisture vapor permeable, air permeable, viral barrier, heat sealable, microporous membrane materials useful in the present invention preferably comprise a polymeric microporous membrane having a matrix of pores comprising continuous passages extending through the thickness of the membrane and opening into the opposite surfaces of the membrane. The polymer used to prepare the microporous membrane useful in the present invention preferably contains a fluorochemical oxazolidinone compound or a fluorochemical aminoalcohol compound which migrates to an air interface, thereby lowering the surface energy of the faces of the membrane as well as the walls of the pores in the membrane, and enhancing the hydrophobic properties of the microporous membrane as well as rendering the microporous membrane material oleophobic.
The microporous membrane materials useful in the present invention can be tailored to have moisture vapor permeability rates over a broad range without adversely impacting their water repellencies, but it is preferable to have a moisture vapor transmission rate (MVTR) of at least 1000 g/m 2 /24 hrs., more preferably a MVTR of at least 2000 g/m 2 /24 hrs., and most preferably a MVTR of at least 5000 g/m 2 /24 hrs.
"Moisture vapor permeable" is used herein to describe microporous membrane materials which readily permit the passage of water vapor through the fabric but which do not allow the passage of liquid water.
The term "water repellent" is used herein to describe microporous membrane materials which are not water wettable and are capable of preventing the passage of liquid water through the membrane material by capillary action under varying ambient atmospheric conditions, including water impinging on the surface of the membrane material.
The term "hydrophobic" is used herein to describe microporous membrane materials which are not wet by liquid water or aqueous body fluids such as blood, saliva, perspiration and urine, and which are capable of repelling and preventing the passage of liquid water through their structure.
The term "oleophobic" is used herein to describe microporous membrane materials which are not wet by oils, greases or body fluids which contain oily components such as perspiration and are capable of preventing the passage of oils and greases through their structure.
The term "heat sealable" is used herein to describe microporous membrane materials which can be sealed together using a hot bar, ultrasonic, or other thermal process sealer to form a bond having a bond strength of at least 0.1 kg/cm width.
The thermally induced phase separated oleophobic, hydrophobic, moisture permeable, air permeable, heat sealable, microporous membrane materials useful in the present invention can, for example, be made by the following steps: (a) melt blending into a homogeneous blend, a mixture comprising about 40 to about 80 parts by weight of a crystallizable olefin polymer, about 20 to 60 parts by weight of a processing compound which will dissolve the polymer at the polymer's melting temperature but which will also phase separate from the polymer on cooling to a temperature at or below the crystallization temperature of the polymer, and 1 to 5 parts by weight of the fluorochemical oxazolidinone or fluorochemical aminoalcohol compound; (b) forming a film from the melt blended mixture; (c) cooling the film to a temperature at which phase separation occurs between the processing compound and the polymer, thereby creating a phase separated film comprising an aggregate of a first phase comprising particles of olefin polymer in a second phase comprising the processing compound and the fluorochemical oxazolidinone or fluorochemical aminoalcohol compound, with adjacent olefin polymer particles being distinct but having a plurality of zones of continuity; and (d) stretching the phase separated film in at least one direction to separate adjacent particles of olefin polymer from one another to provide a network of inter-connected micropores and to permanently attenuate the olefin polymer in the zones of continuity to form fibrils. Optionally, other materials such as dyes, pigments, antistatic agents and nucleating agent may also be added in step (a). Such methods are described, for example, in U.S. Pat. No. 4,539,256 (Shipman), U.S. Pat. No. 4,726,989 (Mrozinski), U.S. Pat. No. 4,863,792 (Mrozinski) and U.S. Pat. No. 5,120,594 (Mrozinski), which are incorporated herein by reference.
The preferred phase separated films typically are solid and generally transparent before stretching and comprise an aggregate of a first phase of particles of olefin polymer in a second phase of the processing compound and the fluorochemical oxazolidinone or fluorochemical aminoalcohol compounds. The particles may be described as spherulites and aggregates of spherulites of the olefin polymer, with processing compound and the fluorochemical oxazolidinone or fluorochemical aminoalcohol compounds occupying the space between particles. Adjacent particles of polymer are distinct, but they have a plurality of zones of continuity. That is, the polymer particles are generally substantially, but not totally, surrounded or coated by the processing compound and the fluorochemical oxazolidinone or fluorochemical aminoalcohol compound. There are areas of contact between adjacent polymer particles where there is a continuum of polymer from one particle to the next adjacent particle in such zones of continuity.
On stretching, the polymer particles are pulled apart, permanently attenuating the polymer in zones of continuity, thereby forming the fibrils and creating minute voids between coated particles which results in a network of interconnected open micropores. Such permanent attenuation also renders the article permanently translucent. On stretching, the processing compound and the fluorochemical oxazolidinone or fluorochemical aminoalcohol compound remain coated on or substantially surrounding the surfaces of the resultant fibril/particle matrix such that the micropores remain open and unfilled. The degree of coating depends on several factors, including, but not limited to, the affinity of the compound and the fluorochemical, oxazolidinone or the fluorochemical aminoalcohol compound for the surface of the polymer particle, whether the compound is liquid or solid, and whether stretching dislodges or disrupts the coating. After the stretching operation, substantially all of the particles appear to be connected by fibrils and are usually at least partially coated. The size of the micropores is easily controlled by varying the degree of stretching, the amount of processing compound employed, melt-quench conditions, and heat stabilization procedures. For the most part, the fibrils do not appear to be broken by stretching, but they are permanently stretched beyond their elastic limit so that they do not elastically recover to their original position when the stretching force is released. As used herein, "stretching" means such stretching beyond the elastic limit so as to introduce permanent set or elongation to the microporous membrane material.
The melting and crystallization temperature of an olefin polymer, in the presence of a processing compound, is influenced by both an equilibrium and a dynamic effect. At equilibrium between liquid and crystalline polymer, thermodynamics require that the chemical potentials of the polymer in the two phases be equal. The temperature at which this condition is satisfied is referred to as the melting temperature, which depends upon the composition of the liquid phase. The presence of a diluent, e.g., the processing compound, in the liquid phase will lower the chemical potential of the polymer in that phase. Therefore, a lower melting temperature is required to re-establish the condition of equilibrium, resulting in what is known as a melting temperature depression.
The crystallization temperature and melting temperature are equivalent at equilibrium. However, at non-equilibrium conditions, which are normally the case, the crystallization temperature and melting temperature are dependent on the cooling rate and heating rate, respectively. Consequently, the terms "melting temperature" and "crystallization temperature," when used herein, are intended to include the equilibrium effect of the processing compound as well as the dynamic effect of the rate of heating and cooling.
The thermally induced phase separated microporous membrane materials useful in the present invention preferably have a microporous structure generally characterized by a multiplicity of spaced, i.e., separated from one another, randomly dispersed, non-uniform shaped, equiaxed particles of olefin polymer connected by fibrils which are intimately surrounded by the processing compound and the fluorochemical oxazolidinone or fluorochemical aminoalcohol compound. "Equiaxed" means having approximately equal dimensions in all directions.
Nucleating agents as described in U.S. Pat. No. 4,726,989 (Mrozinski) may also be used in the preparation of the microporous membrane materials useful in the present invention. The use of nucleating agents provides various advantages including lower polymer content and thus higher porosity of the finished article, reduced polymer particle size resulting in more particles and fibrils per unit volume, greater stretchability resulting in longer fibril length, and greatly increased tensile strength of the material.
Other types of microporous membrane useful in the present invention include those prepared from polyolefin resin, an inorganic particulate filler and a fluorochemical compound capable of providing viral barrier properties, the membranes being stretched in at least one direction. U.S. Pat. No. 3,844,865 (Elton) and U.S. Pat. No. 5,317,035 (Jacoby et al.) describe microporous membranes prepared from polyolefin resin or resin blends and filler material and are incorporated herein for that purpose.
Polyolefins useful in the particle-containing microporous membranes include, for example, polypropylene, polyethylene, ethylene-propylene block copolymers, polybutylene, a-olefin polymers, and combinations thereof.
Inorganic particulate fillers which can be used are solid inorganic alkali earth metal salt particles which are non-hygroscopic, light-colored, water insoluble, easily pulverized, finely divided, and have densities below about 3 g/cc and melting points above olefin degradation temperatures. Particularly preferred is calcium carbonate, although other inorganic salts may be used such as, for example, alkaline earth metal carbonates and sulfates, particularly magnesium carbonate, calcium sulfate and barium sulfate.
Crystallizable olefin polymers suitable for use in the preparation of microporous membrane materials useful in the present invention are melt processable under conventional processing conditions. That is, on heating, they will easily soften and/or melt to permit processing in conventional equipment, such as an extruder, to form a sheet, film, tube, filament or hollow fiber. Upon cooling the melt under controlled conditions, suitable polymers spontaneously form geometrically regular and ordered crystalline structures. Preferred crystallizable polymers for use in the present invention have a high degree of crystallinity and also possess a tensile strength of at least about 70 kg/cm 2 (1000 psi).
Examples of commercially available suitable crystallizable polyolefins include polypropylene, block copolymers or copolymers of ethylene and propylene, or other copolymers, such as polyethylene, polypropylene and polybutylene copolymers, which can be used singularly or in a mixture.
Materials suitable as processing compounds for blending with the crystallizable polyolefin to make the microporous membrane materials useful in the present invention are liquids or solids which are not solvents for the crystallizable polymer at room temperature. However, at the melt temperature of the crystallizable polymer the compounds become good solvents for the polymer and dissolve it to form a homogeneous solution. The homogeneous solution is extruded through, for example, a film die, and on cooling to or below the crystallization temperature of the crystallizable polymer, the solution phase separates to form a phase separated film. Preferably, these compounds have a boiling point at atmospheric pressure at least as high as the melting temperature of the polymer. However, compounds having lower boiling points may be used in those instances where superatmospheric pressure may be employed to elevate the boiling point of the compound to a temperature at least as high as the melting temperature of the polymer. Generally, suitable compounds have a solubility parameter and a hydrogen bonding parameter within a few units of the values of these same parameters for the polymer.
Some examples of blends of crystalline olefin polymers and processing compounds which are useful in preparing microporous materials in accordance with the present invention include: polypropylene with mineral oil, dioctylphthalate, or mineral spirits; and polyethylene-polypropylene copolymers with mineral oil or mineral spirits. Typical blending ratios are 40 to 80 weight percent polymer and 20 to 60 weight percent processing compound.
A particular combination of polymer and processing compound may include more than one polymer, i.e., a mixture of two or more polymers, e.g., polypropylene and polybutylene, and/or more than one processing compound. Mineral oil and mineral spirits which are substantially non-volatile at ambient conditions are examples of mixtures of processing compounds, since they are typically blends of hydrocarbon liquids. Similarly, blends of liquids and solids may also serve as the processing compound. Hydrocarbons suitable for use include both liquids and solids. The liquids are generally mixtures of various molecular weights and with increasing weight become more viscous, i.e., light to heavy mineral oils having a carbon chain length of at least about 20, and with increasing molecular weight become gels, such as petroleum jelly, and then solids, such as waxes having a carbon chain length of about 36.
Other types of microporous materials can also be useful in the present invention as long as the pore size is sufficiently small and pore size distribution is sufficiently narrow that when the fluorochemical compound is present, the article formed provides viral barrier properties. Such microporous materials include, for example, those formed from polytetrafluoroethylene as described in U.S. Pat. No. 3,953,566 (Gore), U.S. Pat. No. 3,962,153 (Gore) and U.S. Pat. No. 4,096,227 (Gore) and those formed from thermoplastic materials as described in U.S. Pat. No. 5,055,338 (Sheth et al.) and U.S. Pat. No. 4,929,303 (Sheth). Useful thermoplastic materials include polyolefin, nylon, polyester, polyphenylene oxide, polystyrene, polyvinyl chloride, polyvinyl acetate, polyvinyl alcohol, polymethyl-methacrylate, polycarbonate and polysulfone.
While the preferred form of the microporous membrane materials useful in the present invention is a sheet or film form, other article shapes are contemplated and may be formed. For example, the article may be in the form of a tube or filament or hollow fiber. Other shapes which can be made according to the disclosed process are also intended to be within the scope of the invention.
Fluorochemical oxazolidinones suitable for use in preparing microporous materials in accordance with the present invention include those described in U.S. Pat. No. 5,025,052 (Crater et al.) which is incorporated herein by reference.
Fluorochemical aminoalcohol compounds suitable for use in preparing microporous materials in accordance with the present invention include, for example, those disclosed in U.S. Pat. No. 3,870,748 (Katsushima et al.), U.S. Pat. No. 4,084,059 (Katsushima et al.) which are incorporated by reference herein and Plenkiewicz et al., "Synthetic Utility of 3-(Perfluoro-1,1-Dimethyl-1-Propene. Part II. Synthesis of New 2-Hydroxy-3-(Perfluoroalkyl)Propyl-Amines", Journal of Fluorine Chemistry, vol. 45, pp 389-400 (1989). The fluorochemical oxazolidinones and aminoalcohol compounds useful in the present invention preferably contain at least about 20 weight percent fluorine, more preferably at least about 30 weight percent fluorine.
These oxazolidinone and aminoalcohol compounds are preferably normally blended in the polymer/processing compound mixture in the proportion of 1 to 5 weight percent. More preferably the fluorochemical oxazolidinone and aminoalcohol compounds are added to the polymer/processing compound mixture in the proportion of 1 to 2 weight percent. Fluorochemical oxazolidinone and aminoalcohol compounds can be added to the membranes of the present invention in amounts greater than 5 weight percent (i.e. 10 weight percent), but additions in excess of about 2 weight percent typically do not show any performance advantages.
Certain conventional additive materials may also be added to the microporous material in limited quantities. Additive levels should be chosen so as not to interfere with the formation of the microporous membrane material or to result in unwanted exuding of the additive. Such additives may include, for example, dyes, pigments, plasticizers, UV absorbers, antioxidants, bacteriostats, fungicides, ionizing radiation resistant additives, and the like. Additive levels should typically be less than about 10% of the weight of the polymer component, and preferably be less than about 5% by weight.
The microporous membranes used in the surgical gowns and drapes of the invention may also be laminated or layered with other porous materials such as woven cloth, non-woven fabric such as non-woven scrim, or foam material. The use of such additional materials should preferably not affect prevention of viral pathogen transmission or porosity.
The articles provided by the present invention include surgical gowns, drapes, masks, gloves, sterile wraps, wound dressings and waste disposal bags, and descriptions of such articles are found, for example, in U.S. Pat. No. 3,856,005 (Sislian); U.S. Pat. No. 4,976,274 (Hanssen); U.S. Pat. No. 4,845,779 (Wheeler et al.); U.S. Pat. No. 3,911,499 (Benevento et al.); U.S. Pat. No. 4,920,960 (Hubbard et al.); U.S. Pat. No. 4,419,993 (Petersen); U.S. Pat. No. 3,426,754 (Bierenbaum et al.); U.S. Pat. No. 4,515,841 (Dyke); UK Application No. 2,232,905A (Woodcock).
In the following non-limiting examples, all parts and percentages are by weight unless otherwise indicated. In evaluating the materials of the invention and the comparative materials, the following test methods are used.
Porosity
Porosity is measured according to ASTM-D726-58 Method A and is reported in Gurley seconds/50 cc.
Bubble Point
Bubble point values represent the largest effective pore size measured in microns according to ASTM-F-316-80 and is reported in microns.
Moisture Vapor Transmission Rate (MVTR)
Moisture vapor transmission rates (MVTR) were made using ASTM-E96-80 Upright Water Method, low humidity on one side and high humidity on the other. The test chamber conditions were 38° C. and 20% relative humidity. Results are reported in g/m 2 /24 hr.
Sweat Contamination Resistance
Resistance to sweat contamination was measured according to MIL-C-44187B, Mar. 31, 1988, test method 4.5.7 with water permeability being determined by Fed. Test Method Std. No. 191A, and is reported as being resistant or not resistant, i.e. pass or fail.
Resistance to Viral Penetration by a Blood-Borne Pathogen
To determine a membrane's viral barrier property as in a surgical gown application, ASTM Test Method ES 22-1992 was followed. Basically, this test indicates whether a virus-containing liquid penetrates the test material. A test pressure of 13.8 kPa (2 psi) is applied through the liquid to the test material. The non-liquid-containing side of the test material is then swabbed and the swabbed exudate is cultured for 24 hours. The number of viruses is then counted. Three samples are tested. The test material has distinguishable viral barrier properties if the number of viruses is less than 100 for each sample tested. However, the number of viruses is preferably less than about 10, more preferably zero for each sample tested.
Viral Penetration When Membrane is Stretched
To determine to what degree a membrane can be stretched without affecting the viral barrier property, the following procedure was used. Prior to applying the pressure to the liquid when using the previously described test method (Resistance to Viral Penetration) a one-inch (2.54 cm) line was drawn on the membrane test sample. Then, the pressure was applied to the membrane. While under pressure, the drawn line was re-measured (including the curvature) while applying the pressure. The % stretch was calculated by the following formula: ##EQU1##
Resistance to Viral Penetration After Sweat Contamination
To determine viral penetration after sweat contamination, membrane samples are exposed to synthetic perspiration according to MIL-C-44187B, Mar. 31, 1988, test method 4.5.6, and then tested for viral penetration using ASTM Test Method ES 22-1992. Using MIL-C-44187B, synthetic sweat was applied to both sides of the membrane and a test pressure of 27.6 kPa (4 psi) was applied for 16 hours. Following this exposure to synthetic sweat, the membrane was tested for resistance to viral penetration by a blood-borne pathogen using ASTM Test Method ES 22-1992. The number of viruses is then counted. Three samples are tested. The test material has distinguishable viral barrier properties if the number of viruses is less than 100 for each sample tested. However, the number of viruses is preferably less than about 10, more preferably zero for each sample tested.
EXAMPLES
OXAZOLIDINONE PREPARATION
The fluorochemical oxazolidinone (FCO) used to prepare the microporous membrane materials in the following examples was similar to that described in U.S. Pat. No. 5,025,052 (Crater et al.) Example 1, except that the alcohol and isocyanate reactants used to prepare the oxazolidinone were C 8 F 17 SO 2 N(CH 3 )CH 2 CH(CH 2 Cl)OH and OCNC 18 H 37 , respectively.
Example 1
A 0.08 mm thick sheet of microporous membrane material was prepared using a thermally induced phase separation technique combining about 64.7 parts polypropylene (PP) having a melt flow index of 0.8 dg/min ASTM 1238 (available from Himont Incorporated, Wilmington, Del. under the trade designation PRO-FAX 6723), about 0.3 parts fluorocarbon oxazolidinone (FCO) compound, and about 35 parts mineral oil (MO), (available from AMOCO Oil Company under the trade designation AMOCO White Mineral Oil #31 USP Grade). The PP/FCO/MO composition was melt extruded on a twin screw extruder operated at a decreasing temperature profile of 260 to 193° C. through a slip gap sheeting die having an orifice of 35.6×0.05 cm and quenched in a water bath maintained at 53° C. The membrane was continuously width stretched or oriented (cross direction) in a tenter oven to a 1.6:1 stretch ratio at 83° C. and heat annealed at 121° C. Membrane characterization data and barrier results are reported in Table I.
Example 2
A 0.06 mm thick sheet of microporous membrane material was prepared using the same materials and process as Example 1, except the materials ratio was 49.5/5.5/45.0, PP/FCO/MO, stretching was at a continuous length direction stretch ratio of 1.25:1 at 50° C. followed by a continuous width direction stretch ratio of 1.75:1 at 83° C., and heat annealing was at 121° C. Membrane characterization data and barrier results are reported in Table I.
Example 3
A 0.05 mm thick sheet of microporous material was prepared using the same materials and process as Example 1, except the materials ratio was 63.7/1.3/35, PP/FCO/MO, stretching was carried out at a continuous length direction stretch ratio of 1.25:1 at 50° C. and a width direction stretch ratio of 2.25:1 at 83° C. and heat annealing was at 121° C. Membrane characterization data and barrier results are reported in Table I.
Example 4
A 0.04 mm thick sheet of microporous membrane material was prepared using the same materials and process as Example 1, except a blue pigment in polypropylene (available from PMS Consolidated, Somerset, N.J. under the trade designation BLUE P293C) was added to color the existing material. The blend ratio of materials was 63.7/1.3/2.0/33.0, PP/FCO/BLUE/MO. In the process, a molten blend maintained at 205° C. was cast from a slip gap sheeting die with a 38.1×0.05 cm orifice onto a smooth steel casting wheel maintained at 66° C. The membrane was then continuously length direction stretched at a ratio of 1.75:1 and continuously width direction stretched 2:1 at 93° C. and heat annealed at 130° C. This membrane was subjected to 20.7 kPa (3 psi) within the Viral Penetration Test and the % stretch was calculated to be 25%. Membrane characteristics and barrier results are reported in Table I.
Examples 5 and 6
A 0.03 mm thick sheet of microporous membrane material was prepared for lamination to a polypropylene spunbonded nonwoven using the same materials as Example 4, except a polybutylene (PB) copolymer (available from Shell Chemical Company under the trade designation PP 8510) was added to make a blend ratio of 61.8/1.3/2.0/5.0/30, PP/FCO/BLUE/PB/MO.
This composition was melt extruded through a circular blown film die having a diameter of 30.5 cm and an orifice of 0.05 cm to form a 2 mil film with a lay flat width of 91 cm. The membrane was continuously length stretched to a 1.6:1 stretch ratio at 38° C. and heat annealed at 119° C. The membrane was then thermally laminated to a 1.0 ounce polypropylene spunbond nonwoven (trademarked "Celestra", supplied by Fiberweb). The laminating process included running an assembly consisting essentially of the membrane and nonwoven between a smooth roll and a heated point-bonding roll (approximately 15 percent point contact) such that the heated point bonding roll applied heat exogenously at spaced-apart points to create a thermal point bonded, viral barrier laminate. The heat roll was set at 270° F. The pressure applied to the materials was approximately 250 pounds per lineal inch. The characterization data and viral barrier results of this membrane/nonwoven laminate, representing Example 5, are reported in Table I.
The same membrane was also adhesively bonded to a similar 1.0 ounce PP spunbonded nonwoven. The adhesive used was a polybutylene resin made by Shell, identified as DP9891D Duraflex, spray applied in a random pattern. The adhesive weight applied was approximately 2 g/m 2 . The characterization data and viral barrier results of this membrane/nonwoven laminate, representing Example 6, are reported in Table 1.
Example 7
The same membrane described in Example 2 was challenged at 20.7 kPa (3 psi) test pressure during the Resistance to Viral Penetration Test, as described above, rather than the standard 13.8 kPa (2 psi) test pressure. At this higher pressure, the % stretch was calculated to be 20%. Membrane characterization data and barrier results are reported in Table I.
Comparative Example C1
A 0.04 mm thick sheet of microporous membrane material was prepared using the same materials, ratio and process as Example 1, except the FCO was omitted from the formulation, and the PP/MO blend was cast as a blown film using the same conditions as in Examples 5 and 6. Then the film was length direction stretched to a 1.85:1 stretch ratio at 38° C. and heat annealed at 119° C. Membrane characterization and barrier results are reported in Table I.
TABLE I__________________________________________________________________________ RESISTANCE BUBBLE MVTR VIRAL TO SWEATEx. CALIPER % POROSITY POINT (g/m.sup.2 / RESIST CONTAMINATIONNo. (mm) FCO (sec/50 cc) (μm) 24 hr) (Pass/Fail) Before/After__________________________________________________________________________1 0.08 0.3 60 0.52 8070 0-0-0 P/P2 0.06 5.5 184 0.26 7489 0-0-0 P/P3 0.05 1.3 382 0.15 7008 0-0-0 P/P4 0.04 1.3 200 0.28 6954 0-0-0* P/P5 0.03 1.3 221 0.40 -- 0-0-0* --6 0.03 1.3 295 0.32 5151 0-0-0 --7 0.06 5.5 184 0.26 7489 0-0-0* P/PC1 0.04 0.0 233 0.33 6490 >600 P/F >600 >600__________________________________________________________________________ *Example 4 and Example 7 passed the Resistance to Viral Penetration Test at 20.7 kPa (3 psi) (other membrane examples were tested at 13.8 kPa (2 psi)), even though the 20.7 kpa (3 psi) stretched Example 4 by 25% and Example 7 by 20%.
Example 1 is especially significant because of the large pore size of the membrane and the small amount of FCO utilized to render it liquid repellent.
Example 8
A 0.03 mm (1.2 mil) thick sheet of microporous membrane material was prepared using the same materials and process as Example 4, except blue pigmented polypropylene (BPP) designated BN-AP, available from Hoechst-Celanese was added and the materials ratio was 58.5/4.3/1.5/35.7, PP/BPP/FCO/MO, stretching was at a continuous length direction stretch ratio of 1.8:1 at 50° C. followed by a continuous width direction stretch ratio of 1.6:1 at 83° C. and heat annealing was at 121° C.
Membrane characterization data and barrier results were determined to be as follows: porosity--158.3 sec/50 cc, bubble point--0.25 μm, MVTR--7722, resistance to viral penetration--0--0--0, resistance to sweat contamination--pass, resistance to viral penetration after sweat contamination--0--0--0.
Example 9
N-methyl-N-glycidyl-perfluorooctanesulfonamide ("epoxide A") was prepared by placing 450 grams N-methyl-perfluorooctanesulfonamide ("amide A") in a two-liter three-necked round-bottom flask and heating to 80° C., 101 grams epichlorohydrin was then added followed by 91 grams methanol. The temperature was reduced to 65° C. before 30 grams 25 wt % sodium methoxide in methanol solution was slowly added keeping the temperature below 70° C. 60 grams 50 wt % aqueous sodium hydroxide solution was slowly added keeping the temperature below 70° C. After addition the reaction was stirred at 65° C. overnight. Water-aspirator vacuum was applied to the flask and excess methanol and epichlorohydrin were removed. 450 grams water was then added to the flask with stirring at 65° to wash the product. The water was decanted after allowing the product to settle. This washing step was repeated a second time. Vacuum was applied to 20 mm Hg and the temperature of the flask was raised to 90° C. to remove volatile materials.
In a one-liter, three-necked round bottom flask fitted with a mechanical stirrer, condenser, gas inlet tube, thermometer, and electric heating mantel were placed 250.0 g (0.44 moles) of epoxide A and 250 mL toluene solvent under a nitrogen blanket. To this stirred solution heated to 60° C. was added 118.4 g (0.44 moles) octadecylamine in small portions over a 15 minute period. After addition of the amine was complete the temperature of the reaction was raised to 115° C. and the reaction was stirred for 12 hours at this temperature until all of the starting epoxide had been converted to aminoalcohol as determined by gas chromatographic analysis. The reaction mixture was cooled to a temperature of about 25° C. and excess toluene solvent was removed under vacuum with a rotary evaporator. Infrared, proton NMR, and mass spectroscopic analysis confirmed the product to be a fluorochemical aminoalcohol of this invention having the structure C 8 F 17 --SO 2 N(CH 3 )CH 2 --CH(OH)CH 2 NH--C 18 H 37 .
A 0.035 mm thick sheet of microporous membrane material was prepared using 59.3 weight percent of the polypropylene (PP) and 35.5 weight percent of the mineral oil (MO) used in Example 1, 3.7 weight percent blue pigmented polypropylene (BPP) designated BN-AP, available from Hoechst-Celanese, and the 1.5 weight percent of the fluorocarbon aminoalcohol prepared as described above. These materials were processed on a 40 mm twin screw extruder using a decreasing temperature profile of 270° C. to 205° C. through a slip gap sheeting die with a 38.1×0.05 cm orifice onto a smooth chill roll maintained at 63° C. The resulting membrane was biaxially oriented 1.9:1×1.6:1 at 94° C. and heat annealed at 130° C. Membrane characterization data and barrier results were determined to be as follows: porosity--131 sec/50 cc; bubble point--0.22 μm; and resistance to viral penetration--0-6-0.
Example 10
A 0.076 mm thick sheet of microporous membrane material was prepared using 58.9 weight percent of the polypropylene and 36.7 weight percent of the mineral oil used in Example 1, 3.1 weight percent blue pigmented polypropylene designated BN-AP, available from Hoechst-Celanese, and 1.5 weight percent of the fluorocarbon aminoalcohol prepared as described above. These materials were processed on a 40 mm twin screw extruder using a decreasing temperature profile of 270° C. to 177° C. through a slip gap sheeting die with a 38.1×0.05 cm orifice onto a pyramid 100 patterned casting wheel maintained at 38° C. The resulting membrane was oriented 1.9:1 at 60° C. and heat annealed at 94° C. Membrane characterization data and barrier results were determined to be as follows: porosity--754 sec/50 cc; bubble point--0.15 μm; and resistance to viral penetration--0--0--0.
Examples 11-14 and Comparative Example C2
For Examples 11-14, a hydrophilic microporous nylon membrane (NYLAFLO, 0.20 μm pore size, available from Baxter Scientific Products) was dipped in a solution containing 2.0 weight percent fluorochemical composition until wet out, about 10 seconds. The fluorochemical compositions were: Example 11--fluorochemical oxazolidinone in trichloroethane; Example 12--TEFLON 1600 (amorphous fluoropolymer available from DuPont Co.) in FLUORINERT-75 (fluorochemical liquid available from 3M Company); Example 13--ZONYL (fluoroacrylate monomer available from DuPont Co.) polymerized in situ as described in U.S. Pat. No. 5,156,780 and Example 14--fluorochemical piperazine in toluene solvent. The membranes were then dried to remove solvent. The treated membranes were tested for porosity and resistance to viral penetration. In Comparative Example C2, an untreated NYLAFLO microporous membrane was tested for porosity and resistance to viral penetration. The results are set forth in Table II.
TABLE II______________________________________ Porosity Viral ResistanceExample (sec/50 cc) (Pass/Fail)______________________________________C2 25 >600->600->60011 222 0-0-012 27 0-0-013 37 0-0-014 616 0-147-1______________________________________
Examples 15-16 and Comparative Example C3
For Examples 15-16, a hydrophilic acrylic microporous membrane (VERSAPOR-450, 0.45 μm pore size, available from Baxter Scientific Products) was dipped in a solution containing 2.0 weight percent fluorochemical composition until wet out, about 10 seconds. The fluorochemical compositions were: Example 15--FC-3537 (a fluoroacrylate polymer, available from 3M Company) in ethyl acetate; and Example 16--N-methylperfluorooctane-sulfonamidoethyl stearate in toluene. The membranes were then dried to remove solvent. The treated membranes were tested for porosity and resistance to viral penetration. In Comparative Example C3, an untreated VERSAPOR-450 microporous membrane was tested for porosity and resistance to viral penetration. The results are set forth in Table III.
TABLE III______________________________________ Porosity Viral ResistanceExample (sec/50 cc) (Pass/Fail)______________________________________C3 7.5 >600->600->60015 20 0-0-016 65 14-1-0______________________________________
The fluorochemical piperazine used in Example 14 was prepared as follows:
To a 1-L round bottom flask, equipped with a magnetic stir bar, was added 51.7 g anhydrous piperazine and 200 mL methylene chloride. With slight cooling of the reaction vessel with a cold water bath, 75.3 g perfluorooctanesulfonyl fluoride was added over a 5-10 minute period. The resulting yellow solution was allowed to stir for an additional 2 hrs, then ice chips were added followed by addition of ice cold deionized water. The layers were separated and the organic layer was washed with two additional portions of deionized water. After drying over anhydrous sodium sulfate, the solvent was removed under reduced pressure. Distillation (0.65-0.70 mm, 140-142° C., first cut, was discarded) yielded 52.4 g N-(perfluorooctanesulfonyl piperazine.
To a 500 mL round bottom flask equipped with a magnetic stir bar and a nitrogen inlet was added 25.6 g of the N-(perfluorooctanesulfonyl piperazine and 150 mL methylene chloride. A solution of 13.6 g stearoyl chloride in 50 mL methylene chloride was added dropwise to the reaction vessel. After addition was complete, slight heating was applied to ensure complete reaction. After stirring overnight, the solvent was removed under reduced pressure. The residue was taken up in chloroform and washed with three portions of deionized water and one portion of saturated aqueous sodium chloride solution. After drying over anhydrous sodium sulfate, the solvent was removed under reduced pressure, to yield a compound of the formula ##STR2##
Example 17 and Comparative Example C4
In Comparative Example C4, a microporous membrane was prepared according to U.S. Pat. No. 5,317,035 by melt blending 50 weight percent ethylene/propylene copolymer (HIFAX RA-061™, available from Himont, Inc., 35 weight percent of a polypropylene/calcuim carbonate blend (PF-85F™ containing 60 weight percent polypropylene having a melt flow rate of 4.0 and 40 weight percent calcium carbonate, mean particle size 0.8 microns, available from A. Schulman, Inc.) and 15 weight percent low molecular weight polypropylene resin (PROFLOW™-1000, melt viscosity 137 poise measured at 136 sec-1 and 190° C., available from Polyvisions, Inc.) using a 25 mm twin screw extruder maintained at a decreasing temperature profile from 249° C. to 215° C. at a throughput rate of 1.8 kg/hr through a sheeting die with a 30.5 cm×0.508 mm orifice onto a steel casting wheel maintained at 93° C. to form a cast film 0.127 mm thick. The film was stretched 2×2 on a T.M. LONG™ film stretcher at 91° C. The film was heat set at 82° C. for 10 minutes.
In Example 17, a microporous membrane was prepared and oriented in a manner similar to that of Comparative Example C4 except 1.5 weight percent FCO was added to the melt blend of Comparative Example C4 based on total film weight.
Samples of membrane of each of Example 17 and Comparative Example C4 were tested for porosity, bubble point pore size, and resistance to viral penetration. The results are set forth in Table IV.
TABLE IV______________________________________ Bubble Point Porosity Viral ResistanceExample (μm) (sec/50 cc) (Pass/Fail)______________________________________C4 1.01 111 0-20-30017 0.83 150 0-0-0______________________________________
Example 18
A microporous membrane was prepared by melt blending 89.6 weight percent of a 60:40 weight ratio blend of linear low density polyethylene:calcium carbonate (FLP 697-01, available from A. Shulman, Inc.), 9.9 weight percent linear low density polyethylene (ASPUN™ XU61800.31, melt flow index 150, available from Dow Chemical Company) and 1.5 weight percent FCO using a 25 mm twin extruder operated at 1.8 kg/hr and 254° C. and cast onto a smooth casting wheel maintained at 93° C. to form a 0.13 mm thick membrane. The resultant membrane was stretched 1.5×2.5 at 100° C. and was heat set at 79° C. for 15 minutes. The results of membrane testing were:
Porosity: 90 sec/50 cc
Bubble Point: 0.22 μm
Thickness: 0.065 mm
Viral Resistance: 0--0-15
The various modifications and alterations of this invention will be apparent to those skilled in the art without departing from the scope and spirit of this invention and this invention should not be restricted to that set forth herein for illustrative purposes. | The invention discloses a method of preventing transmission of viral pathogens between a source of viral pathogens and a target of said viral pathogens comprising positioning between said source and said target a microporous membrane material comprising (1) a thermoplastic polymer or polytetrafluoroethylene and (2) a water- and oil-repellent fluorochemical compound which provides said membrane with oleophobic, hydrophobic and viral barrier properties. | 8 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention concerns a method for continuously mixing and degassing liquid, castable media, in particular components of casting resins and, where called for, fillers such as quartz dust, aluminum oxide or dyes, using a continuous degassing apparatus as well as equipment for carrying out the method.
2. Description of the Prior Art
An apparatus and a procedure for continuously degassing casting resin is known from the German patent document 42 22 695 A1. During the resin casting, the resins or hardeners may have to be mixed with fillers such as quartz dust, Mikrodol (ground dolomite), aluminum oxide and the like, or with further substances such as dyes, and must be degassed under vacuum in order that the products made from such casting-resin formulations, for instance electrically insulating parts, be endowed with the required properties. Whereas the mixtures of the resin/filler or hardener/filler are prepared in so-called formulating operations, and then are delivered to the end processor, other end consumers carry out such formulations of the mixtures of resin/filler or hardener/filler themselves. Typically such operations are carried out batch-wise.
When the end processor implements the formulation, the components as a rule also are degassed, and consequently, material is available batch-wise for processing. If such material is delivered from a formulation operation, it requires being set to the proper temperature and be degassed before being processed. Such a procedure entails uneconomical work stoppages if the consumption of one batch is followed by a wait for a subsequent batch. Therefore, the typical procedure calls for such charges being sufficient for one or two work shifts a day and that replenishment, or new metering and mixing, be carried out in the time remaining, preferably at night. As a result the supply containers and mixers must be commensurately large. If, on the other hand, casting material must be available around the clock, then all batch mixers must be kept ready. These batch mixers are present upstream in front of the supply containers from which the material will then be processed. Besides the corresponding expense in construction, the supplies of material must wait for substantial durations, sometimes hours, prior to procvessing. Moreover, there are significant initial delays until processing starts. Again such batch mixers, even when designed as so-called thin-layer degassing mixers, require comparatively long mixture degassing-times because the better degassed mixture flowing back from the discharge cone into the batch is constantly being mixed with the batch as yet not optimally degassed. Illustratively, such a thin-layer degassing mixer is known from the German patent document 30 26 429 A1.
In the light of the above state of the art, it is the object of the invention to create a method, and implementing equipment as initially defined above, making continuously available components of casting resin in homogeneous and degassed form for further processing. The present invention requires less expensive construction and, as compared to the total amount of material present in the facility, being operative with small and already pre-formulated amounts of material.
SUMMARY OF THE INVENTION
The present invention overcomes the drawbacks of the prior art as the liquid components, or at least one liquid component and the filler are fed in metered manner into a continuous degassing apparatus.
Consequently, a component of casting resin and a filler for instance may be fed into the continuous degassing apparatus and already several minutes later they may arrive ready for processing. Substantial quantities of supplies are no longer involved and, therefore, the material always undergoes the same stress due to temperature, time and mixing. Moreover, the components are moved through short paths. The method of the invention allows continuously mixing and degassing both several liquid components and at least one liquid component and a filler.
The German patent document 42 22 695 A1 describes one feasible embodiment of a continuous degassing apparatus, this patent document being explicitly referred to here for its disclosure content where pertinent. The apparatus is used for continuously degassing casting resin, that is an already preformulated component. The apparatus comprises a housing fitted with an intake and an outlet for transmitting a casting-resin component and is connected to a vacuum source. Several zones are formed inside the housing which are crossed sequentially by the casting resin for its step-wise degassing, each zone being associated with means for depositing the casting resin on degassing surfaces particular to the zones and with means to transfer the casting resin into the next zone. As a result the apparatus of the German patent document 42 22 695 A1 achieves continuous degassing of a casting-resin component, without, however, simultaneous mixing into predetermined recipe portions taking place. In the invention, on the other hand, such an embodiment of the continuous degassing apparatus is used not only for degassing, but, at the same time, for degassing and mixing components of casting resin, and where called for including a filler.
In case of need, and as provided for in a first embodiment of the invention, the liquid components, and if so desired the filler, are premixed in metered ratios and then are fed into the continuous degassing apparatus. As a result mixing the liquid components and possibly the filler precedes degassing. In such a case the continuous degassing apparatus may be made more compact.
The metering of the liquid components, for instance the resin and the filler, may be carried out in the invention volumetrically and/or gravimetrically in order to obtain in this manner the particular recipe ingredients.
In an especially advantageous manner of the invention, the liquid components and optionally the filler, are continuously fed into the continuous degassing apparatus, whereby again slight quantities of supply, short paths for the components and corresponding homogeneity of the particular casting-resin component will be achieved.
As regards equipment, the problem of the invention is solved in that metering means for the liquid components, or for the at least one component and the filler, are provided upstream of the continuous degassing apparatus, again a mixer being insertable if desired between the metering means and the degassing apparatus. The mixer may be designed to be especially small, for instance as a so-called batch mixer.
In one embodiment of the invention, the mixer also may be integrated into the continuous degassing apparatus, a result of which the equipment may be made especially compact. Advantageously, identical drives, that is a single drive, shall be used, approximately in such manner that the mixing element, of the mixer and the rotational element of the continuous degassing apparatus depositing the casting-resin component on the corresponding degassing surfaces and wiping them off, shall be mounted on a common drive shaft.
The invention further allows at least two mixers being loaded with, and discharging, in mutually opposite directions, liquid components as well as a filler. Such tandem operation allows continuous material feed to the continuous degassing apparatus.
An alternative embodiment of the invention also allows designing the mixer as a continuous mixer, so that continuous feeding of preformulated material to the continuous degassing apparatus is possible.
Use can be made in the invention of volumetric metering means such as metering pumps, gear pumps, piston-cylinder systems, oval wheel meters, metering screws, etc., however, gravimetric metering means may also be used, for instance weighing scales or the like. Preferably, the metered filler will be added gravimetrically, whereas the recipe portion of the at least one liquid component shall be implemented volumetrically. Obviously the amount of filler may also be determined volumetrically using a metering worm, with the worm rotation being sensed by an incremental pickup.
If no mixer is present upstream of the continuous degassing apparatus, the filler stored at atmospheric pressure must be reliably fed into the continuous degassing apparatus in such manner that vacuum failure shall be precluded. In this respect the invention recommends to implement the metering of the filler into the continuous degassing apparatus through a pressure shutoff element 22 or lock which in its open state will feed the filler, for instance quartz dust, in metered manner into the continuous degassing apparatus.
In one conception of the invention, the continuous feed of preformulated material from the mixer into the continuous degassing apparatus can be achieved in that an intermediate container follows the mixer and simultaneously acts as an intermediate storage or buffer.
In case a mixer precedes the continuous degassing apparatus, said apparatus will be fitted with a product intake. If the liquid components and the filler, or resin and quartz dust, are directly fed into the continuous degassing apparatus, at least two product intakes will be present. However, both liquid components, that is for instance resin and hardener, also may be fed jointly into the continuous degassing apparatus and the filler will be fed into the second intake.
Further purposes, advantages, features, and applicabilities of the present invention are elucidated in the following description and in relation to the attached drawings. All described and/or graphically shown features are an object of the invention, whether per se or in arbitrary meaningful combination, and also independently of their summarization in the claims.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 depicts a schematic of a mixing and degassing apparatus according to one embodiment of the invention partly shown in section.
FIG. 2 depicts a schematic of a mixing and degassing apparatus according to an alternate embodiment of the invention partly shown in section.
FIG. 3 depicts a schematic of a mixing and degassing apparatus according to another alternate embodiment of the invention partly shown in section.
FIG. 4 depicts a schematic of a mixing and degassing apparatus according to another alternate embodiment of the invention partly shown in section.
FIG. 5 depicts a schematic of a mixing and degassing apparatus according to another alternate embodiment of the invention partly shown in section.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 shows casting-resin processing equipment, in particular, making possible mixing and degassing a liquid component and a filler. The equipment comprises a supply container 15 for the liquid component which is fed through a pump 19 acting as a metering means 2, a heater 18 inserted into the feed line and a subsequent valve 21 to a mixer 3, in particular a small batch mixer.
The filler in this selected embodiment, for instance quartz dust, for the one liquid component of the casting resin, is held in a silo 16 and can be moved by a conveyor system 20 into a supply vessel 17. From the supply vessel 17 the filler is also moved by a metering worm 9 into the mixer 3. The casting-resin component, for instance the resin, is mixed with the filler in the mixer 3. The mixer 3 is fitted for that purpose with a mixing element 6 driven into rotation by the mixer drive 27. The recipe portion of the resin introduction can be determined volumetrically for instance by the metering pump 19. The recipe portion also can be determined gravimetrically using the weighing scale 10 mounted on the mixer 3 as shown in FIG. 1. Preferably, the filler addition is implemented by using the weighing scale 10 to measure the weight of the mixer, weighing scale stopping the metering worm 9 by means of a control or regulation circuit, for instance by means of the control system 23, when the particular recipe portion has been reached. Thereupon the mixer 3 starts operating and mixes the liquid component and the filler within a given time interval.
The shutoff element 21, inserted in the feed line to the continuous degassing apparatus 1, is closed during the addition of the liquid component and filler and during mixing. The valve 21 opens after termination of mixing and the preformulated mixture is aspirated through the product intake 12 into the continuous degassing apparatus 1. A vacuum pump 24 preceded by the valve 21 is hooked-up to the continuous degassing apparatus 1. Continuous transit of the casting resin being fully degassed takes place in the continuous degassing apparatus 1. Illustratively, the design of the continuous degassing apparatus may be that as described in the German patent document 42 22 695 A1. FIG. 1 merely shows the drive 5 of the components of the continuous degassing apparatus, the drive 5 also comprising the rotary assembly 7 in the form of a drive shaft with means 28 to deposit the casting resin on and to wipe it off the degassing surfaces 29, as shown in more detail in the further Figures. The degassed component of casting resin together with the added filler is then fed through a metering pump 19 to a continuous mixer 25, the second component, in particular the hardener, also being fed through a continuous degassing apparatus 1, only partly shown, and a further metering pump 19 to the continuous mixer 25. An omitted casting valve may be present at the discharge of the continuous mixer 25 in order to feed the mixed casting resin to a casting mold (also omitted). Also a small collecting vessel 26 for the subsequent metering pumps 19 is provided in both component arms.
To prevent air from the mixer 3 at atmospheric pressure from breaking into the continuous degassing apparatus 1 at vacuum, the weighing scale 10 shown in FIG. 1, or for instance a filling-level probe (omitted), are provided to detect the particular filling level in the mixer 3 and to close the valve 21 when there is an appropriate minimum of this filling level.
By appropriately changing the equipment of FIG. 1, preformulated casting resin also may be continuously fed to the continuous degassing apparatus 1. For that purpose two mixers 3 operating in tandem are provided, in such manner that the casting resin of one of the mixers 3 will be discharged into the continuous degassing apparatus 1 when the other mixer 3 is being filled with casting resin and filler at the particular recipe ratio, in order to carry out its mixing.
In the further embodiments identical references denote the components corresponding to those of FIG. 1 and accordingly individual description is omitted.
The substantial difference between the embodiment of FIG. 2 compared to that of FIG. 1 is that an intermediate container 11 is mounted between the mixer 3 and the continuous degassing apparatus 1, said container 11 acting as a storage means for the preformulated casting resin coming from the mixer 3 and allowing continuous feed of casting resin to the continuous degassing apparatus 1.
The equipment of FIG. 3 makes possible the preparation of finished casting resin. The two liquid components, that is the hardener on one hand and on the other hand the resin, which are being received in the particular supply containers 15, and further the filler received in the supply vessel 17, are fed continuously and synchronously without any interposed mixer to the continuous degassing apparatus 1 which then assumes the function of mixing and degassing. Metering of casting resin and hardener is volumetrically carried out by the metering pumps 19, whereas the filler feed at the desired recipe portion takes place gravimetrically by means of the weighing scale 10 associated to the conveyor worm 9. For that purpose an elastic coupling element is mounted into the feed line between the metering element 2 and the product intake 13.
Two mutually inert liquid components such as resin and flexibilizer also may be supplied in the equipment of FIG. 3 by means of the supply containers 15.
In the presently discussed embodiment, the pressure in the filler storage-vessel 17 is matched to the pressure of the vacuum in the continuous degassing apparatus 1, and for that reason a vacuum pump 24 is connected to the supply vessel 17. As a result, air invasion from the supply vessel 17 into the continuous degassing apparatus 1 is prevented. On the other hand, the feed of the liquid components, namely resin and hardener, does not critically affect air invasion of the continuous degassing apparatus 1 provided that the liquid level in the supply containers 15 be above the suction apertures of the suction lines of the pumping means 19 dipping into the supply containers 15.
As shown, the continuous degassing apparatus 1 comprises at least two product intakes 13, 14 in the case of direct feed of liquid component and filler.
The embodiment of FIG. 5 differs from those of FIG. 3 foremost in that a mixer 4, i.e. a mixing zone, is integrated into the continuous degassing apparatus 1. As shown by FIG. 4, a single-unit drive 5 for the mixer element 6 of the mixer 4 and for the rotary means 7 of the continuous degassing apparatus 1 having deposition and wiping means 28 is provided with a single drive shaft, thereby substantially reducing the scope of construction.
In the embodiment of FIG. 5, a continuous mixer 8 precedes the continuous degassing apparatus. This feature offers the advantage that the preformulated component is continuously fed to the continuous degassing apparatus 1 and as a result the configuration of mixers 3 operating in mutually opposite directions can be dropped.
In case that as in the embodiment of FIG. 5 the continuous mixer 8 is at atmospheric pressure, such atmospheric pressure also must be present in the supply vessel 17. If on the other hand the continuous mixer 8 is at vacuum, a corresponding relative negative pressure must be present in the supply vessel 17. | A method for continuously mixing and degassing liquid, castable media, in particular components of casting resin or a casting-resin component with a filler such as quartz dust, aluminum oxide or dyes, and the equipment with which to implement the method. One object of the invention is to assure that casting-resin components are available in homogeneous and degassed form for further processing by either liquid components or a liquid component and a filler which are metered into a continuous degassing apparatus (1). | 1 |
This is a division of U.S. patent application Ser. No. 08/699,129 filed Aug. 16, 1996, now U.S. Pat. No. 5,743,070 issued Apr. 28, 1998.
This invention relates to packaging machinery and more particularly to a packaging machine and method of packaging which are especially well suited for loading relatively bulky and liquid products sequentially into bags of a novel, side interconnected, chain of bags.
BACKGROUND OF THE INVENTION
U.S. Pat. No. 4,969,310 issued Nov. 13, 1990 to Hershey Lerner et al. under the title Packaging Machine and Method and assigned to the assignee of this patent (the SP Patent) discloses and claims a packaging machine which has enjoyed commercial success. One of the major advantages of the machine of the SP Patent resides in a novel conveyor belt mechanism for gripping upstanding lips of bags of a chain as they are transported along a path of travel and registered at a load station. The firmness with which the lips are gripped makes the machine highly suitable for packaging bulky products which are stuffed into the bags. While the machine of the SP Patent was an advance over the prior art, especially in terms of its lip gripping capability, even greater lip gripping capabilities, if achieved, would be useful in enabling packaging of additional products. Expressed another way, the bag gripping forces of the machine of the SP Patent were dependent on clamping pressure applied between pairs of belts. Thus, while the machine was a definite advance over the art, as to any given bag size, it has a finite maximum stuffing pressure it can withstand without slippage.
Since the bag gripping is dependent on the force with which belt pairs are clamped, the length of the path of travel through the load station is limited. Thus the length of a bag along the path of travel is limited, loading of a bag while it moves along the path of travel is not possible and the concurrent loading of two or more bags is not available.
With the machine of the SP Patent there is an intermittent section which includes the loading station and a continuous section which includes a sealing station. Since the section including the loading station is intermittent, obviously the through-put of the machine is inherently less than could be achieved with a continuously operating loading section.
The machine of the SP Patent had further advantages over the prior art, including an adjustable bag opening mechanism which was adapted to accept a wide range of bag sizes and adjustable to provide a range of bag openings. While an advance over the prior art, the bag openings were six sided so that, like most of the prior art, a rectangular bag opening was not achievable.
Although one prior machine provides rectangular openings, the dimensions of the rectangular openings, both longitudinally and transversely, are limited both by the construction of the chain of bags being filled and by guide rods used to transport the bags. Thus, if an operator wished to change from one opening size to another, another and different web of bags was required. Moreover, to the extent, that the packaging machine could be adjusted to vary the configuration of the rectangular opening, such available adjustment was extremely limited because it required substitution of a different set up guide rods. Further, there was excessive packaging material waste in the form of elongate tubes which slid along the guide rails.
While the machine of the SP Patent has been sold under the designation SP-100V for vertical orientation in which products can be gravity loaded into bags and the designation SP-100H for horizontal loading of stuffable products, neither machine was suitable for adjustment from horizontal to vertical and return, nor for orientation at selected angles of product insertion between the horizontal and the vertical.
A problem has been experienced with prior art sealers having pairs of opposed belts to transport bags through a seal station. The problem is that too frequently due to weight of the products there is slippage of bags relative to the belts and sometimes of the bag fronts relative to the backs resulting in poor seal quality. Alternatively or additionally it is too often necessary to provide a conveyor or other support for bags as they are transported through the sealer station.
SUMMARY OF THE INVENTION
With the machine of the present invention, the described problems of the prior art and others are overcome and an enhanced range of available packaging sizes is achieved. In its preferred form the machine has two, independently moveable carriages which are selectively rigidly interconnected. One of these carriages supports a novel and improved bagging section, while the other supports a closure mechanism. The disclosed closure mechanism is a novel and improved sealing section. Because the machine has two separable carriages other closure carriages supporting other closure mechanisms such as bag ties and staples can readily be used.
Each of the sections is rotatably mounted on its carriage, such that once coupled the two sections may be rotated together about a horizontal axis for product loading, by gravity and/or stuffing when in the vertical and by stuffing when in the horizontal. Advantageously the two sections may also be oriented in any one of a set of angular orientations between the horizontal and the vertical.
A major feature of the present machine is that the loading section opens the bags into rectangular configurations. Not only are the bag load openings rectangular configurations, but the transverse and longitudinal dimensions of such openings for any given bag size are relatively and readily adjustable over a wide range.
The machine may be operated in either a continuous or an intermittent mode at the operator's selection. Both sections are operated in the same mode. That is if the loading section is continuous, so too is the sealing section, while both operate in the intermittent mode at the same times.
One of the outstanding advantages of the invention resides in the utilization of a novel and improved mechanism for gripping upstanding lips of bags as they are transported through the load section. This mechanism utilizes conveyor belts of a type more fully described in a concurrently filed application of Hershey Lerner entitled Plastic Transport System, attorney docket 14-160 (the Belt Patent). The Belt Patent is incorporated in its entirety by reference. Gripping is achieved by coaction of the bags upstanding lips and unique belts such that belt clamping mechanisms are neither required or relied on. To this end a pair of main transport belts are provided and positioned on opposite sides of a path of web travel. In the preferred and disclosed embodiment, each main belt has an upstanding lip contacting surface with a centrally located, transversely speaking, lip receiving recess preferably of arcuate cross-sectional configuration. A pair of lip transport belts of circular cross-section are respectively cammed into the main transport belt recesses to force bag lips into the recesses and fix the lips with a holding power far in excess of that achieved with the prior art.
Since the gripping of bag lips for support is accomplished through coaction of the bag lips and the conveyor belts, there is essentially no limit to the length of the loading station. Rather multiple numbers of open bags can be concurrently conveyed through the loading station. With a machine operating on a continuous basis and a synchronized product supply conveyor adjacent the load station, one is able to concurrently transfer a set of products into a like numbered set of bags with the transfer progressing concurrently as the bags and the conveyed products advance through the load station.
Another advantage of an elongated load station is that one may position a series of vibrator feeders along the station. As an example, a first vibratory feeder could deposit a desired number of bolts in a bag at a first location, a second feeder a like number of washers at a second location downstream from the first, and a third feeder a like number of nuts at a third location still further downstream; thus, eliminating the need for a feed conveyor.
With this arrangement extremely high rates of packaging can be achieved. For example, it is possible to load and seal 130 ten inch bags per minute. Rates achieved with the present machine are rates in excess of those that can be achieved with virtually all, if not all, prior art machines including so called "form and fill" machines.
Another feature of the invention resides in a novel and improved mechanism for breaking frangible interconnections between adjacent sides of successive bags. Assuming the machine to be in its gravity fed horizontal mode, this mechanism comprises a belt which is trained about spaced pulleys which are rotatable about respective horizontal axes. The belt has projecting pins. The belt pulleys are rotated to move the belt in synchronism with positioning of a chain of bags being fed through the load section to cause one of the pins to break the frangible bag interconnections each time a set of such interconnections is longitudinally aligned with the belt.
Moving in the downstream direction of the machine to consider other advances, another feature of the invention is in a novel and improved mechanism for adjusting the width of the load station by varying the spacing between the pairs of main and lip transport belts. This adjustment, which is infinite between maximum and minimum limits, coupled with the novel and improved bag web, provides a wide range of available transverse and longitudinal dimensions of rectangular bag openings for any given chain of like sized interconnected bags.
As loaded bags exit the load station it is desirable to advance the lead side edge and retard the trailing side edge of each bag of a chain to bring inside surfaces of the top portions of each bag back into surface to surface touching orientation for sealing. To this end a novel planetary mechanism is provided. This mechanism is driven by the moving bags themselves to effect the stretching action and reestablish inside surface to surface relationship. For larger bags oppositely directed jets of air are employed which are effective to reestablish the surface to surface orientation.
At an exit from the bagging section of the machine, the main transport belts overlie exit belts which in turn overlie the closure section transport belts, such that the closure section picks up the now longitudinally stretched top surfaces of each loaded bag. As the bags are transferred to the closure section belts, a rotary knife cuts the bags near their tops such that the lip portions that have been carried by the main transport belts are cut off and become recyclable scrap. The elevation of the cutter relative to the heat sealer is adjustable so that the extent to which upper portions of the bags are cut away provides loaded bags sized to be neat, and if desired tight, finished packages.
In order to prevent excessive heating of bags passing through the sealing section and the sealing section belts, the heat source for effecting the seals is shifted away from loaded bags and the belts when the machine is stopped and moved to a location adjacent the bags when the bags are moving. Thus, a mechanism is provided for shifting the heat sealer from a seal forming position to a storage position and return in synchronism with cycling of the machine when in the intermittent mode.
As the loaded bags pass through the seal section, a series of longitudinally aligned, juxtaposed and individually biased, pressure members act against one of the seal section conveyor belts. These pressure members bias the one belt against the bags and thence against the other belt to in turn bias the other belt against a backup element to maintain pressure on the bag tops as they are transported through the seal section. Advantageously, unlike a prior machine of similar construction, individual coil springs are used to bias the pressure members.
The belts used in the seal section are novel and improved special belts which are effective substantially to prevent any product weight induced slippage of the bags relative to the belts. The novel belts are also effective to resist longitudinal movement of the face and back of each bag relative to one another and to the belts. One provision to prevent this relative slippage is providing belts which have corrugated belt engaging surfaces with the corrugations of one belt interlocking with the corrugation of the other to produce a serpentine grip of the face and back of each bag. Further, the preferred belts are metal reinforced polyurethane to provide enhanced resistance to belt stretching. A glue and grit mixture may be applied to the surfaces of the sealer belts, further to inhibit bag slippage. A urethane coating is applied over the glue and grit to complete the improvements provided for the prevention of bag slippage.
The belts of the sealer section are driven by a stepper motor through a positive drive, so that the sealer stepper motor in synchronism with bagger stepper motor maintain belt and bag feed rates of travel that are consistent throughout the length of path of bag travel from supply through to finished package.
Lips of the bags which project from the seal section conveyor belts are heated by a contiguous heat tube sealer having an elongate opening adjacent the path of bag lip travel. Heated air and radiation emanating from this sealer effect heat seals of the upstanding lips to complete a series of packages.
Because the machine sections, unlike the machine of the SP Patent, are either both continuous or both intermittent during machine operation, successive bags passing through the closure section are juxtaposed rather than spaced. This juxtaposition provides improved sealing efficiency and sealer belt life.
A web embodying the present invention is an elongate, flattened, thermoplastic tube having face and back sides which delineate the faces and backs of a set of side by side frangibly interconnected bags. The tube includes an elongate top section which is slit to form lips to be laid over and then fixed in the main transport belts. The top section is interconnected to the bags by face and back, longitudinally endless, lines of weakness which are separated from each side edge toward the center of each bag to the extent necessary to achieve the desired rectangular openings. Thus, the present web is far simpler and less costly than the web of the prior system that provided rectangular bag openings.
The invention also encompasses a process of packaging which includes gripping the upstanding front and back lip portions between main and lip transport belts. The belts are then spread as they pass through a load station pulling bag openings into rectangular configurations as portions of bag tops are separated from the upper lip section. After bag loading, top portions of the bag inner surfaces are returned to abutting engagement, a portion of the lip section is trimmed from the bags, and the bags are sealed or otherwise closed to complete packages.
Accordingly, the objects of this invention are to provide novel and improved packaging machine, packaging materials and methods of forming packages.
IN THE DRAWINGS
FIG. 1 is a top plan view of the machine of the present invention;
FIG. 2 is a fragmentary top plan view of the bagger section of the machine of FIG. 1 and on an enlarged scale with respect to FIG. 1;
FIG. 3 is a foreshortened elevational view of the bagger section as seen from the plane indicated by the line 3--3 of FIG. 1;
FIG. 4 is a perspective view of the novel and improved bag web of the present invention showing sections of the transport belts transporting the web through the load station and a novel mechanism for providing spacing of the sides of loaded bags particularly of a small size;
FIG. 5 is a perspective view of a portion of the bag flattening mechanism shown in FIG. 4 and on an enlarged scale;
FIG. 6 is a fragmentary perspective view on the scale of FIG. 5 showing an alternate arrangement to the mechanism of FIG. 5 for flattening bags;
FIGS. 7 and 8 are enlarged sectional views from the planes respectively indicated by the lines 7--7 and 8--8 of FIG. 4 show the main and lip transport belts together with a fragmentary top portion of the bag as bag lips are folded over the main transport belts and then trapped in the grooves of the main belts;
FIG. 9 is a sectional view of the bag flattening or stretching mechanism of FIGS. 4 and 5 as seen from the plane indicated by the line 9--9 of FIG. 2;
FIG. 10 is an enlarged sectional view of the mechanism of FIG. 9 as seen from the plane indicated by the line 10--10 of FIG. 2;
FIG. 11 is an enlarged, fragmentary, sectional view of the transport belt spacing adjustment mechanism as seen from the plane indicated by the lines 11--11 of FIG. 2;
FIG. 12 is an elevational view of a portion of the machine as seen from the plane indicated by the line 12--12 of FIG. 1 showing a bag support conveyor underneath the loading and seal sections;
FIG. 13 is an elevational view of the seal section on an enlarged scale with respect to FIG. 12;
FIG. 14 is an elevational view of the angular orientation maintenance mechanism on an enlarged scale with respect to other of the drawings and as seen from the plane indicated by the line 14--14 of FIG. 12;
FIG. 15 is an enlarged sectional view of the sealer positioning mechanism and a bag support conveyor as seen from the plane indicated by the lines 15--15 of FIG. 13;
FIG. 16 is a sectional view of a web guide as seen from the plane indicated by the line 16--16 of FIG. 3;
FIG. 17 is a sectional view of the lip plow as seen from the plane indicated by the line 17--17 of FIG. 3;
FIG. 18 is an enlarged plan view of a force application element and a fragmentary plan view of the sealer belts;
FIG. 19 is an enlarged fragmentary plan view of a transfer location between the bagger and the closure sections, including a knife for trimming the tops of loaded bags prior to closure;
FIG. 20 is a further enlarged sectional view of the structure of FIG. 19 as seen from the plane indicated by the line 20--20 of FIG. 19;
FIG. 21 is a still further enlarged view of the knife and its height adjustment mechanism as seen from the plane indicated by the line 21--21 of FIG. 20;
FIG. 22 is a plan view of an alternate and preferred sealer for the, closure section; and,
FIG. 23 is an elevational view of the sealer of FIG. 22.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
I. The Overall Machine
Referring to FIGS. 1 and 4 a web 15 of side connected bags is provided. The web 15 is fed from a supply shown schematically at 16 to a bagger section 17. The bagger section 17 is separably connected to a sealer section 19. The bagger and sealer sections respectively include wheeled support carriages 20, 21. The support carriages 20, 21 respectively include support frames for supporting bagging and sealing mechanisms.
In the drawings the bagging and sealing mechanisms are shown in their vertical orientations for, gravity loading. The machine will be described in such orientation it being recognized that, as described more fully in section IV, the mechanisms may be positioned in a horizontal orientation and at other angular orientations.
II. The Web 15
The web 15 is an elongated flattened plastic tube, typically formed of polyethylene. The tube includes a top section 23 for feeding along a mandrel 24, FIGS. 4 and 16. The top section 23 is connected to the tops of a chain of side connected bags 25 by front and back lines of weakness in the form of perforations 27, 28. Frangible connections 30 connect, adjacent bag side edges, FIGS. 3 and 4. Each bag 25 includes a face 31 and a back 32 interconnected at a bottom 33 by a selected one of a fold or a seal. Side seals adjacent the interconnections 30 delineate the sides of the bags 25. The bag faces and backs 31, 32 are respectively connected to the top section 23 by the lines of weakness 27, 28, such that the top section 23 when the web is flattened itself is essentially a tube.
III. The Bagger Section 17
A. A Bag Feed and Preparation Portion 35
The web 15 is fed from the supply 16 into a bag feed and preparation portion 35 of the bagger section 17. The feed is over the mandrel 24 and past a slitter 36, FIG. 4. The slitter 36 separates the top section 23 into opposed face and back lips 38, 39. The feed through the bag feed and preparation portion 35 is caused by a pair of endless, oppositely rotating, main transport belts 40, 41 supported by oppositely rotating pulley sets 42, 43. The main belts 40, 41 are driven by a stepper motor 44, FIG. 3 through toothed pulleys 42T, 43T of the sets 42, 43. Other of the pulleys 42S, 43S are spring biased by springs S, FIG. 2, to tension the belts.
A plow 45 is provided and shown in FIGS. 3, 4 and 17. For clarity of illustration the slitter and the plow have been omitted from FIG. 1. The plow is positioned a short distance upstream from a roller cam 46. As the lips are drawn along by the main transport belts 41, 42, the lips 38, 39 are respectively folded over the top bag engaging surfaces 41S, 42S, of the main transport belts under the action of the plow 45 as depicted in FIG. 7.
Once the lips are folded over the tops of the main transport belts 41, 42, the roller cam 46 presses endless, lip transport and clamp belts 48, 49 into complemental grooves 51, 52 in the main transport belts 41, 42 respectively. Thus, the grooves 51, 52 function as bag clamping surfaces that are complemental with the clamping belts 48, 49. More specifically, the clamp belts are circular in cross section, while the grooves 51, 52 are segments of circles, slightly more than 180° in extent. The camming of the clamp belts into the grooves traps the lips 38, 39 between the clamp belts and the grooves. The lip clamping firmly secures the lips between the coacting belt pairs such that the lips, due to their coaction with the belts, are capable of resisting substantial stuffing forces as products are forced into the bags at a load station 60. Sections of the clamp belts which are not in the grooves 51, 52 are trained around a set of lip transport belt pulleys 50.
A bag side separator mechanism 53 is provided at a bag connection breaking station. The separator mechanism 53 includes an endless belt 54 which is trained around a pair of spaced pulleys 55 to provide spans which, as shown in FIGS. 3 and 4, are vertical. The pulleys 55 are driven by a motor 57, FIG. 2. As the belt is driven breaking pins 58 projecting from the belt 54 pass between adjacent sides of bags to break the frangible interconnections 30. Thus, as the bags depart the bag feed and preparation portion 35, they are separated from one another but remain connected to the lips 38, 39.
B. The Load Station 60
The load station 60 includes a pair of parallel belt spreaders 61, 62. The belt spreaders are mirror images of one another. As is best seen in FIG. 11, the belt spreaders respectively include channels 63, 64. The channels 63, 64 respectively guide the main transport belts 40,41, on either side of the load station 60. When the transport belts 40,41, are in the channels 63, 64, as is clearly seen in FIGS. 4 and 11, the bags 25 are stretched between the belts in a rectangular top opening configuration.
A schematic showing of a supply funnel 66 is included in FIG. 4. As suggested by that figure, the products to be packaged are deposited through the rectangular bag openings each time a bag is registered with the supply funnel at the load station.
A space adjusting mechanism is provided. This mechanism includes a spaced pair of adjustment screws 68, 69, FIG. 2. The adjustment screw 68, 69 are respectively centrally journaled by bearings 70, 71. The screws have oppositely threaded sections on either side of their bearings 70, 71 which threadably engage the belt spreaders 61, 62. Rotation of a crank 72 causes rotation of the adjustment screw 69. The screw 69 is connected to the screw 70 via belts or chains 73, which function to transmit rotation forces so that when the crank 72 is operated the screws 68, 69 are moved equally to drive the spreaders equally into an adjusted spacial, but still parallel, relationship.
As the spreaders are movably adjusted toward and away from one another, the spring biased pulleys 42S, 43S maintain tension on the main transport belts 40, 41 while permitting relative movement of spans of the belts passing through the spreader channels 63, 64. Similarly, spring biased lip transport belt pulleys 50S maintain tension on the clamp belts 48, 49. The spring biased pulleys of both sets are the pulleys to the right as seen in FIG. 2, i.e. the entrance end pulleys in the bag feed and preparation portion 35.
The main transport pulley sets 42, 43 include two idler pulleys 75, 76 downstream from the load station 60. The idler pulleys 75, 76 are relatively closely spaced to return the main transport belts 40, 41 into substantially juxtaposed relationship following exit from the load station 60.
C. Bag Stretching
As loaded,bags exit the load station, it is desirable to return upper portions of the bag faces and backs into juxtaposition. To facilitate this return with smaller bags a novel and improved planetary stretcher 90 is provided. This planetary bag stretcher is best understood by reference to FIGS. 5, 9 and 10. The stretcher 90 includes a support shaft 92 mounted on frame members 94 of the bagger section, FIG. 10.
The planetary stretcher includes a bag trailing edge engaging element 95. The element 95 includes six bag engaging fingers 96. As is best seen in FIGS. 4 and 5, one of those fingers 96 is shown in a lead one of the bags 25 while the next finger is being moved into the next bag in line as the next bag departs the load station 60. As the bags move from right to left as viewed in FIG. 5, an internal ring gear portion 100 drives a planet gear 102. The planet gear orbits a fixed sun pinion 104. The planet gear is journaled on and carried by a lead edge engaging element 105 journaled on the shaft 92. The lead edge engaging element 105 has four fingers 106 which orbit at one and a half times the rate of the fingers 96. Rotation of the lead edge engaging element causes one of the fingers 106 to enter the next bag as it exits the load station and to engage a leading edge 108 of the bag, thereby stretching the bag until top portions of the bag face and back are brought into juxtaposition.
For larger bags this stretching of the now loaded bags as they exit the load station is accomplished with jets of air from nozzles 110, 112 which respectively blow against the lead and trailing edges of the bag, thus stretching the bags from their rectangular orientation into a face to back juxtaposed relationship as the transport belts are returned to juxtaposition.
D. A Transfer Location
After loaded bags have exited the load station 60 and the face and back of each bag have been brought into juxtaposition, the loaded bags are transferred to the closure section 19 at a transfer location 114. Exit conveyors 115, 116 underlie the main transport belts 40, 41 at an exit end of the bagger section 17. Loaded bags are transferred from the main transport belts to the exit conveyors. The exit conveyors in turn transfer the loaded bags to closure section conveyor belts 118, 119.
Referring to FIGS. 19-21, a rotary knife 120 is positioned a short distance downstream from the exit conveyors. The knife is rotatively mounted in an externally threaded support tube 121. The tube in turn is threadedly connected to a knife support frame section K. An adjustment lock 123 is slidably carried by the frame section K. When the lock 123 is in the position shown in solid lines in FIG. 21, it engages a selected one of a plurality of recesses R in the perimeter of the support tube 121 to fix the knife in an adjusted height position. When the lock 123 is slid to the phantom line position of FIG. 21, the tube 121 may be rotated to adjust the vertical location of the knife 120.
The knife 120 is driven by a motor 122 to sever the bag lip portions 38, 39, leaving only closure parts of the lip portions for closure, in the disclosed arrangement, by heat sealing. The trimmed plastic scrap 124, FIG. 12, from the severed lip portions is drawn from the machine with a conventional mechanism, not shown, and thereafter recycled.
IV. The Closure Section 19
As is best seen in FIG. 1, the novel and improved sealer includes a plurality of independently movable force application elements 125. One of the force elements is shown on an enlarged scale in FIG. 18. The force elements 125 slidably engage the outer surface of a bag engaging run 126 of the belt of the conveyor 119. Springs 128 bias the elements 125 to clamp the bag faces and backs together against a coacting run 130 of the conveyor belt 118. A backup 132 slidably engages the coacting run 130 to resist the spring biased force of the application elements 125.
A stepper motor 134, FIG. 1, is drivingly connected to the closure section conveyor belts 118, 119 to operate in synchronism with the stepper motor 44 of the bagger section, either intermittently or continuously.
As is best seen in FIGS. 13 and 15, a beater tube 135 is provided. A heat element 136, FIG. 15, is positioned within the tube to provide heat to fuse upstanding bag lips when the heater tube 135 is in the position shown in solid lines in FIG. 13. The heat transfer to the lips is effected by both radiation and convection through an elongate slot 135S in the bottom of the tube.
The heater tube 135 is connected to a pair of supports 137, 138. When the bags 25 are vertical the heater tube 135 is suspended by the supports 137, 138. The supports in turn are pivotally connected to and supported by a pair of cranks 140, 142. The cranks 140, 142 are pivotally supported by a section of the frame of the sealer carriage 21. The cranks 140, 142 are interconnected by a rod 144 which in turn is driven by an air cylinder 145. The air cylinder 145 is interposed between the carriage frame and the rod 144. Reciprocation of the air cylinder is effective to move the heat tube between its seal position shown in solid lines and a storage position shown in phantom, FIG. 13. When the conveyor belts 118, 119 are operating to transport bags through the closure section the sealer is down, while whenever the machine is stopped the sealer is shifted to its storage or phantom position of FIG. 13.
As is best seen in FIG. 18, the adjacent runs 126, 130 of the sealer conveyor belts 118, 119 have surfaces that are corrugated and interfitting. These interfittings corrugations provide both enhanced bag gripping and holding power and resistance to relative longitudinal movement of the runs as well as the faces and backs of the bag. The gripping and holding power of the belts is further enhanced by coating the belts with a glue and sand slurry and applying a polyurethane coating over the slurry to further enhance the frictional grip of the belts on bags being transported. The combined effects of the belt corrugations and coating substantially prevent slippage of the bags due to weight in the bags.
V. Section Interconnection and Adjustments
A. Section Interconnection
The bagger and closure sections 17,19 are physically interconnected when in use. In the disclosed arrangement this interconnection includes a pair of lock bars 150. The lock bars which are removably positioned in apertures 151,152 formed in bosses 154,155 respectively projecting from frames of the bagger and closure stations 17,19.
B. Angular Positioning
As has been indicated, the bagger and closure sections are adjustable to horizontal or vertical orientations as well as angular orientations between the horizontal and the vertical.
The bagger section 17 is rotatably supported on a pair of trunions one of which is shown at 157 in FIG. 3. As can best be seen in FIGS. 12 and 13, the sealer section 19 is rotatably supported on the carriage 21 by spaced trunions 170, 172. The trunions 157,170 & 172 are axially aligned. The end trunion 170, to the left as viewed in FIGS. 12 and 13, is associated with an angular position holder. The holder includes an apertured plate 174 secured to and forming part of the frame of the carriage 21, FIG. 14. The plate 174 includes a set of apertures 175 spaced at 15° intervals to provide incremental angular adjustments of 15° each between the horizontal and vertical orientations of the machine. Each of the apertures 175 may be selectively aligned with an aperture in a sealing section plate 176. A pin in the form of a bolt 178 projects through aligned apertures to fix the sealer section and the interconnected bagger section in a selected angular orientation.
VI. A Support Conveyor
While there normally is no need for bottom support of the bags 25 as they pass through the bagger section 17, nonetheless a conventional support conveyor 160 may be provided, see FIG. 3. More frequently a conveyor 162 will be provided under the closure section 19. In either event, suitable height adjustment and locking mechanisms 164 are provided to locate the conveyors 160,162 in appropriate position to support the weight of loaded bags being processed into packages.
VII. The Preferred Sealer
Referring to FIGS. 22 and 23, the preferred sealer for the closure mechanism is disclosed. The sealer includes an air manifold 180 for receiving air from a blower 182. In an experimental prototype a 300 cubic foot per minute variable pressure blower was used to determine optimized air flows and pressures.
The manifold 180 has three pairs of oppositely disposed outlets 184,185,186. Each outlet is connected to an associated one of six flexible tubes 188. The tubes in turn are connected to pairs of oppositely disposed, T-shaped sealer units 190,191,192 to respectively connect them to the outlets 184,185,186. The T-shaped sealer units respectively include tubular legs 190L,191L,192L extending vertically downward from their respective connections to the flexible tubes 188 to horizontal air outlet sections 190H,191H,192H. The outlet sections are closely spaced, axially aligned, cylindrical tubes which collectively define a pair of elongate heater mechanisms disposed on opposite sides of an imaginary vertical plane through the loaded bag path of travel.
Each horizontal outlet section includes an elongate slot for directing air flow originating with the blower 182 onto upstanding bag lips being sealed. Each of the sealer unit legs 191,192 houses an associated heater element of a type normally used in a toaster. Thus air flowing through the T-shaped units 191,192 is heated and the escaping hot air effects seals of the upstanding bag lips. Air flowing through the units 190 is not heated, but rather provides cooling air to accelerate solidification of the seals being formed.
The T-shaped sealer units 190,191,192 are respectively connected to the rod 144 for raising and lowering upon actuation of the air cylinder 145 in the same manner and for the same purpose as described in connection with the embodiment of FIGS. 12 and 13.
A further unique feature of the embodiment of FIGS. 22 and 23 is a vertical adjustment mechanism indicated generally at 194. The vertical adjustment 194 permits adjustment of the slope of the horizontal sections of the T-shaped units 190-192 such that the outlet from 191H is lower than that of 192H. This downward sloping of the heater mechanism in the direction of bag travel assures optimized location of the hot air being blown on the plastic. The location is optimized because as the plastic melts it sags lowering the optimum location for the direction of the hot air. Further the cooling air from the unit 190 is directed onto a now formed bead.
VIII. Operation
The carriages 20, 21 are independently wheeled to a desired location. The two are then physically interconnected by inserting the lock bars 150 into the apertures 151,152.
Assuming the bagger and sealer are in a vertical orientation, the relative heights of the bagger and closure section conveyors are adjusted as is the height of the knife 120. If the angular orientation of the machines is to be adjusted, the bolt(s) 178 is(are) removed and the bagger and sealer section are rotated about the axis of the trunions 157,170, 172 to a desired orientation. Following this rotation the bolt(s) is(are) reinserted to fix the mechanism in its desired angular orientation.
Next a web 15 of bags 25 is fed through the bagger and sealer by jogging the two. The transverse spacing of the main conveyor belts 40, 41 is adjusted by rotating the crank 72 until the load station 60 has the desired transverse dimension. A control, not shown, is set to provide a desired feed rate and a selected one of continuous or intermittent operation. Assuming continuous operation, the feed rate may be as high as 130 ten inch bags per minute,
Once the machine is in operation, the top section 21 of the web 15 is fed along the mandrel 24 and slit by the slitter 36. This forms the lips 38, 39 which are folded over the main transport belts 41, 42 by the action of the plow 45. The lip clamp belts 48, 49 descend from the elevated and spring biased pulleys 50S, as shown in FIG. 3. The roller cam 46 cams the clamp belts 48, 49 respectively into the transport belt recesses 51, 52 to provide very positive and firm support for the bags as they are further processed. As successive side connections 30 of the bags are registered with the bag side separator 53, the motor 55 is operated to drive the belt 54 and cause the breaker pins 58 to rupture the side connections 30.
As adjacent runs of the transport belts 41, 42 progress downstream from the bag feed and preparation portion 35, the belts are spread under the action of the belt spreaders 61, 62. As the belts are spread, the lips 38, 39 cause the front and back faces 31, 32 adjacent the lead edge of each bag to separate from the lips 38, 39 by tearing a sufficient length of the perforations between them to allow the lead edge to become the mid point in a bag span between the belts as the bag passes longitudinally through the load station 60. Similarly, the perforations adjacent the trailing edge are torn as the trailing part of the bag is spread until the bag achieves a full rectangular opening as shown in FIG. 4 in particular.
Next a product is inserted into the rectangular bag as indicated schematically in FIGS. 3 and 4. While the schematic showing is of discrete fasteners, it should be recognized that this machine and system are well suited to packaging liquids and bulky products which must be stuffed into a bag, such as pantyhose and rectangular items, such as household sponges.
After the product has been inserted, the adjacent runs of the main transport belts are brought back together and the loaded bag tops are spread longitudinally of the path of travel either by the planetary stretcher 90 or opposed air streams from nozzles 110, 112.
As is best seen in FIG. 3, exit ones 50E of the lip belt pulley set are spaced from the main transport belt and rotatable about angular axes. Expressed more accurately, when the machine is in a vertical loading orientation, the pulleys 50E are above the main transport belt such that the lip transport belts are pulled from the grooves 51, 52.
The now loaded bags pass through the transfer location onto the exit conveyors 115, 116 and thence to the seal station conveyors 118, 119. At this juncture the scrap 124 is severed from the loaded bags by the action of the knife 120. As the bags are advanced through the sealer section, the heater tube 135 is maintained in its lowered and solid line position of FIGS. 12, 13 and 15. If the machine is operated in its intermittent mode, the cylinder 145 is cycled in coordination with the starts and stops of the intermittently operated machine to shift the heater tube 135 between its solid line seal position and its storage position shown in phantom in the FIG. 13.
Although the invention has been described in its preferred form with a certain degree of particularity, it is understood that the present disclosure of the preferred form has been made only by way of example and that numerous changes in the details of construction, operation and the combination and arrangement of parts may be resorted to without departing from the spirit and the scope of the invention as hereinafter claimed. | A packaging machine and process for loading bags of a novel web of side connected bags are disclosed. The web is fed through a bagger section by a pair of grooved main transport belts and a pair of lip transport belts each disposed in the groove of the associated main belt to trap bag lips in the grooves. Adjustable belt spreaders space reaches of the transport belts as they move through a load station whereby to sequentially open the bags into rectangular configurations. A closure section in the form of a novel and improved heat sealer is releasably connectable to the bagger section. The sections are adjustable together between horizontal and vertical orientations. Processes of opening, closing and sealing side connected bags are also disclosed. | 1 |
FIELD OF THE INVENTION
This invention relates generally to the field of load measuring devices, and more specifically to load measuring devices used in combination with valve operators in the art of valve diagnostics.
BACKGROUND OF THE INVENTION
To understand the prior art upon which the present invention seeks to improve, attention is directed to the specification of U.S. Pat. No. 4,542,649, issued to Charbonneau et al (the "649 Patent"). Specifically, attention is directed to the "Stem Load Calibration Device" in which a load cell disc is suspended by a plurality of rods above a fixed (or relatively fixed) object. In the case of the 649 Patent, the "fixed" object is a valve operator housing. The load disc device of the 649 Patent is of a type which measures compressive forces exerted directly on a load bearing surface of the load cell body by a shaft (or shaft extension) moving relative to the "fixed" housing. There are other load measuring mechanisms with varying arrangements of the load bearing surfaces, shaft blocking components and strain gauges which have attempted, with varying degrees of success, to perform the function of the stem load measuring device of the 649 Patent.
In spite of the availability of numerous load measuring mechanisms, the need for improvements has been noted. For example, the Stem Load Calibration Device of the 649 Patent has found extensive application as part of valve diagnostic equipment utilized to diagnose valve and valve operator conditions within nuclear power plants. When working in a nuclear environment, there exists the desired and need to accomplish tasks as quickly as possible. The 649 Patent, Stem Load Calibration Device and other known load measuring mechanisms include a plurality of separate components which are assembled on site at the valve operator; or, in some cases, the load measuring mechanisms include few parts but require some degree of disassembly and reassembly of the valve operator. A second example of an area for improvement is that many prior art load measuring mechanisms offer no protection against overloading of the valve operator. As such, extremely large and potentially damaging forces can be built up within the operator during the diagnostic process.
SUMMARY OF THE INVENTION
Briefly described, the present invention comprises a load measuring apparatus which can be pre-assembled as a ready-to-use device and portably carried to the location where measurement of the load delivered by a shaft moving relative to a shaft housing is accomplishable with minor or no preparation of the shaft and shaft housing. In the preferred embodiments, the apparatus of the present invention is outfitted for quick screw-in mounting to the existing, threaded pipe tap in the upper bearing housing of an existing valve operator, such as Limitorque Corporation operator models "00", "0", "1" and "2".
The load measuring apparatus of the preferred embodiment of the present invention, briefly, comprises a load bearing body providing a deformable "link" between a shaft housing (such as a valve operator) and a shaft which moves relative to the housing. That same deformable, load bearing body functions as the supports for the shaft engaging element of the invented device. Strain gauges measure the deformation of the load bearing body, which is related to the thrust of the shaft.
In the preferred embodiment, the load measuring apparatus includes an overload shear washer incorporated to prevent damage to the shaft housing by shearing away and allowing continued, unblocked movement of the shaft.
Preferred embodiments of the Load Measuring System of the present invention comprises the Load Measuring Apparatus operating in association with a signal conditioning device and display/recording device by which measurement are conveyed and interpreted.
It is, therefore, an object of the present invention to provide a load measuring apparatus which can be quickly and easily installed at a valve operator.
Another object of the present invention is to provide a load measuring apparatus which is preassembled, portable and ready-to-use with little preparation at the measuring site.
Still another object of the present invention is to provide a load measuring apparatus which provides overload protection.
Yet another object of the present invention is to provide a portable, quickly assembled and operated Load Measuring System.
Other objects, features and advantages of the present invention will become apparent upon reading and understanding this specification when taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a cutaway, side view of the Load Measuring Apparatus of the present invention, showing an embodiment with overload protection.
FIG. 2 is a side view of the Load Measuring Apparatus of FIG. 2 shown mounted on a valve operator, with parts cutaway.
FIG. 3 is a pictorial view of the Load Measuring Apparatus of FIG. 1, installed on a valve operator.
FIG. 4 is an isolated, exploded side view of overload protection features of the Load Measuring Apparatus of FIG. 1.
FIG. 5 is a electrical schematic of Load Measuring System of the present invention.
FIGS. 6A and 6B are representative diagrams showing relative angular placement of strain gauges about the main body member of the Load Measuring Apparatus in accordance with the preferred embodiment of the present invention.
FIG. 7 is a side view, with portions cut away, showing the Load Measuring Apparatus of FIG. 1, with housing mount adaptor.
FIG. 8 is a cutaway, side view of the Ready-to-Use Load Measuring Apparatus of the present invention, showing an alternate embodiment of that of FIG. 1.
FIG. 9 is an isolated view of a connector component of one, alternate embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now in greater detail to the drawings in which like numerals represent like components throughout the several views, the Load Measuring Apparatus 10 of a preferred embodiment of the present invention is seen in FIG. 1 as including a main body member 12, an upper shear nut 13, an end plug 14, a plug cover 15, a shear washer 16, a stem extension 17, a stop washer 18 and a protective sleeve 19.
The main body member 12 is a single elongated, component formed preferably from a material which is rigid and yet elastic within the range of forces anticipated to be exerted on it and which exhibits a known, preferably linear relationship between the amount of force exerted on it and the amount of deformation experienced as results of the exerted force. Steel is the preferred material. The body member 12 is seen as being formed into, basically, three cylindrical portions, the upper portion 24, intermediate portion 25, and the lower portion 26. A cylindrical, axial passage 27 extends through the main body member 12. The upper portion 24 and lower portion 26 are each formed along at least part of their outer circumference with threading 30, 31. The intermediate portion 25 is precisely machined (or otherwise manufactured) to a predetermined outer diameter such that the thickness "a" between the inner wall 34 and outer wall 35 is predetermined thickness along a test region 36 of the intermediate portion 25. Other features of the main body member 12 include: a groove 38 for accepting an "O" Ring to seal against foreign material; and a tap hole 42 for attaching the sleeve 19. An adapter 44 (or adapters) is provided in alternate embodiments to selectively reduce (or enlarge) the diameter of the threaded section 31 of the lower portion 26.
The upper sheer nut 13 is formed with a central passage 46 defined by three inner wall segments 47, 48, 49 (see FIG. 4). Two of the inner wall segments 47, 49 are internally threaded. A ledge 50 is formed between the two lower wall segments 48, 49. A groove 37 is included to accept a sealing "O" Ring.
The end plug 14 is a slightly elongated, disc-shaped component which includes a threaded, central passage 53 and four, threaded screw taps 54. The plug cover 15 is a disc-shaped component including a central passage 56 and four, screw accepting holes 57 passing through the disc. The plug cover 15 and plug 14 are of equal diameters and their screw holes/taps 57, 54 and central passages 56, 53 are in alignment when assembled. The plug cover 15 also includes an annular inset 58 and the screw holes 57 are set radially inward from the annular inset 58. The inner diameter "b" of the annular inset 58 is equal to the inside diameter of the shear washer 16.
The shear washer 16 is of a typical washer shape having: an inside diameter equal to the inner diameter "b" of the annular inset 58; and an outside diameter "d" equal to or less than the inside diameter of the bottom, inner wall segment 49 but greater than the inside diameter of the center, inner wall segment 48 of the shear nut 13. The shear washer 16 is formed from a material of known shear strength ("s"), and the thickness ("t") of the shear washer is precisely determined such that the washer will shear at a predetermined shearing force (as represented by arrows "A"), using the formula [t=shearing force-slπ], "1" being the diameter of the washer at the shear point, which, in the disclosed embodiment is the inside diameter of inner wall segment 48. The material of the shear washer is preferably steel.
The stem extrusion 17 is comprised of an elongated, threaded rod 60 and a head 61 held to the rod by a set screw 62. The stop washer 18 is a disc shaped component having a central passage 64 through which the rod 60, but not the head 61, can pass. The outer periphery 65 of the stop washer 18 is threaded for threaded engagement with the upper, inner wall segment 47 of the shear nut 13. The stop washer 18 is preferably made of a material such as plastic. The protective sleeve 19 is seen as including an amphenal connector 20 mounted thereto.
With reference again to FIG. 1, the Load Measuring Apparatus 10 is also seen as including strain gauges 67, 68 mounted to the test region 36 of the main body member 12. Whereas, in alternate embodiments, measurements are taken using known arrangements of strain gauges utilizing just one, two or more gauges, the disclosed embodiment of the drawings utilizes eight strain gauges 67a, 67b, 67c, 67d, 68a, 68b, 68c, 68d arranged as follows: four gauges 67a-67d are oriented to measure deformation of the test region in the axial direction, that is, aligned with the maximum principal strain. The four, "principal strain" gauges 67a-67d are preferably mounted to the test region 36 at locations equally spaced between the upper and lower chamfers 28, 29 of the body member 12 intermediate portion 25, and are spaced apart with one gauge at every 90 degrees circumferentially about the test region. See FIGS. 6A and 6B. Four other gauges 68a-68d are oriented to measure deformation of the test region 36 in the circumferential direction. These four, "Poisson" gauges 68a-68d are preferably mounted to the test region 36 at locations equally spaced between the upper and lower chamfers 28, 29, adjacent the principal strain gauges 67a-67d, and spaced apart with one poisson gauge at every 90 degrees circumferentially about the test region. See FIGS. 6A and 6B.
The electrical arrangement among the strain gauges 67a-67d, 68a-68d is that of a Wheatstone Bridge 70 as shown, in its preferred arrangement, in the schematic of FIG. 5. The operation of the strain gauges 67, 68 and of the Wheatstone Bridge 70 are as known in the industry and more detailed explanation than given herein is considered unnecessary for clear understanding and performance of the present invention. Each strain gauge 67-68 is, in the herein disclosed embodiment, of the type gauge which exhibits a varying electrical resistance in response to experienced strain. Each gauge represents a resistance in one arm of the Bridge 70. As the compression or tension forces are experienced at the test region 36, the strain experienced by each gauge 67-68 is represented as a change in resistance within the respective arm of the Bridge 70. The "unbalanced" Wheatstone Bridge generates a voltage across terminals "C" and "D". The voltage across terminals "C" and "D" is directed to a signal conditioning device 83.
One embodiment of the present invention, and a preferred method of the present invention, includes the Load Measuring Apparatus 10 and system in conjunction with a valve operator 75 and is used to measure the stem load exerted on the valve steam 77 by the driving mechanism 78 of the valve operator. Attention is directed to FIG. 2. The operator 75 is a valve operator of a type typical of the industry, such as Limitorque Corporation operator model "00", "0", "1" and "2". The valve operator 75 includes a valve shaft 77 driven in an axial direction relative to the operator housing (as indicated by arrows "B") by a motor or hand wheel and gearing arrangement (not shown). The Load Measuring Apparatus 10, although can be transported in pieces and assembled at the location of use, is preferably preassembled to a condition which is ready-to-use with simple mounting of the apparatus 10 to the operator housing. The Load Measuring Apparatus 10 is pre-assembled by placing the shear washer 16 between the end plug 14 and plug cover 15 with the shear washer fit within the annular inset 58 of the plug cover. Screws extending through the screw holes 57 of the plug cover 15 are drawn tightly into the screw taps 54 of the end plug 14 to, thus, draw the end plug and plug cover together in manner of a vise to rigidly grip the shear washer 16 there between. This plug and washer assembly is inserted into the axial passage 27 of the main body 12, as seen in FIG. 1, with the protruding, shear washer 16, resting on the upper edge 32 of the upper, body portion 24. The shear nut 13 is threaded unto the upper portion 24 of the main body thus gripping the protruding shear washer 16 rigidly between the shear nut 13 and the upper portion 24 of the body member 12. Thus, it can be seen that the plugs and washer assembly and the sheer nut combine to define a cap over the body member 12. The stop washer 18 is threaded into the top portion 47 of the shear nut 13, and the threaded rod 60 is inserted through the central passage 64 of the stop washer 18 and through the central passage 56 of the plug cover 15 and then threaded through the central passage 53 of the end plug 14.
The strain gauges 67-68 are mounted to the test region 36 of the body member 12 in accordance with the physical arrangements discussed above; and the gauges 67-68 are connected one to another in the Bridge 70 arrangement discussed above by wiring which is shielded by the protective sleeve 19. Input and output wiring to and from the Bridge 70 are terminated at the amphenol connector 20. The protective sleeve 19 is placed over the body member 12.
The Load Measuring Apparatus 10 is now pre-assembled, and ready-for-use in conjunction with a shaft and housing arrangement such as the valve operator 75, and together with an associated signal conditioning device 83 and, in some embodiments, an appropriate display, recording or calculating device 85. The signal conditioning device 83 is a device which provides appropriate voltage to the Wheatstone Bridge 70; accepts output voltage from the bridge 70 indicating the balance or degree of "out-of-balance" of the Bridge; and provides adjustable amplification for SPAN purposes. The signal conditioning device 83 is connected to the Load Measuring Apparatus 10 through the amphenol connector 20.
The Load Measuring Apparatus 10 is carried, together with the signal conditioning device 83 and appropriate display/recording device 85 to the location of the valve operator 75 which is to be tested. The ease of portability is a factor of the size and weight of the apparatus 10 as determined by the magnitude of force which the apparatus must be designed to test and to withstand. At the test site, the Load Measuring Apparatus 10 is readily mounted to the operator housing 80. In the disclosed embodiment, the particular operator 75 is depicted as a limitorque operator, as expressed above, which includes a centrally threaded, upper bearing plate 88 which is in axial alignment with the valve stem 77. Attention is directed to FIG. 2. The Load Measuring Apparatus 10 is mounted to the valve operator 75 by threading the lower body portion 26 of the body member 12 into the upper bearing plate 88. It is understood that various models of this limitorque design, valve operator 75 are designed with upper bearing plate 88 of larger or smaller central openings 89; and in these alternate embodiments of the housing mount adapter 44 is threaded to the lower body portion 26 (housing mount 26) to appropriately size the lower portion 26 for mounting in the respective bearing plate. (See FIG. 7.) It is further understood that the housing mount will be accomplished in alternate embodiments by methods other than threading, since not all valve operators (and other shaft and housing combinations) include a threaded bearing plate such as that of the Limitorque design.
With the Load Measuring Apparatus 10 mounted to the valve housing 80, the threaded rod 60 is turned to advance the rod through the central passage of the body member 12 until the rod makes contact with valve steam 77. The signal conditioning device 83 is plugged into the amphenol connector 20 and set to provide voltage and receive signals. Preferably, a combination display and recording device 85, such as a recording oscilloscope, is connected to receive output from the signal conditioning device 83. The Load Measuring Apparatus 10 and its associated system are now ready to begin measuring.
The valve operator 75 is operated to begin driving movement of the valve stem 77 in an upward direction (that is, pushing against the threaded rod). As the valve stem pushes on the rod, the upward moving force is transmitted from the rod to the end plug 14, to the shear washer 16, to the shear nut 13 and, thus, the force is transmitted to the body member 12 at the upper portion 24. As the shaft force transferred to the upper body portion 24 pulls on the body member 12 at one end, the body member is held at it's other end by the lower portion 26 mounted to the housing 80. The body member 12 begins to stretch and otherwise deform as does the test region 36 which deforms in amounts related to the force applied by the stem 77, as expressed above. The deformation of the test region 36 is detected by the strain gauge and represented by a change in the balance of resistances in the Wheatstone Bridge 70, as expressed above. The "out-of-balance" voltage signal is directed to the signal conditioning device 83 where it is amplified for SPAN purposes and output to the display device 85. Preferably the amplified signal at the display device 85 will be displayed and recorded in a readily converted ratio, for example, one volt equals 10,000 pounds.
As the force on the valve stem 77 increases and, thus, the force transmitted through the rod 60 to the plug 14 and shear washer 16 increases, the force will eventually cause the operator to cut-off in response to normal torque switch or limit switch operation. If the force reaches the washer's shearing forces, predetermined as above, the shear washer 16 will shear, thus allowing the end plug 14 and rod 60 to move freely within the shear nut and, thus, no force is transferred to the body member 12 or operator housing 80. Therefore, the valve steam 77 will reach its limits and cut off the operator motor in a manner known in the industry. The stop washer 18 acts as a backstop which retains the end plug 14 and rod 60 assembly loosely within the shear nut cavity 46 after shearing of the shear washer 16. The stop washer 18 is of material of sufficient strength to stop the plug and rod from being a projectile, but of low enough strength as to be easily broken by valve stem movement. It will be readily understood by reference to the above-mentioned assembly techniques that a replacement shear washer 16 is quickly and easily installed.
With reference to FIG. 7, the housing mount adapter 44 is seen, in an alternate embodiment, as including an adapter core 98, a core sleeve 101 threaded to the core 98, and adapter shear ring 100 held in a "vise" manner between the core and core sleeve, and an adapter nut 99. The core 98/sleeve 101/ring 100 assembly is held to the lower, mounting portion 26 of the body member 12 by threading the adapter nut 99 to the lower portion 26 and gripping the protruding ring 100 between the adapter nut and the lower edge 33 of the body member 12. This assembly functions similar to the shear washer 16 arrangement above. If the force exerted by the valve stem 77 exceeds the shearing force of this lower shear ring 100, the entire body member 12 moves away from the adapter core 98, which is retained within the valve housing 80.
In an alternate embodiment, an appropriately threaded sleeve connector 92 is threaded onto the top of the valve stem and then the threaded rod is threaded into the top of the sleeve connector; after which the main body member 12 of the Load Measuring Apparatus 10 is lowered onto and screwed into the housing. In this way, the valve stem interacts with the threaded rod as the stem moves in both axial directions. Reference is made to FIG. 9.
Another alternate embodiment of the present invention is seen in FIG. 8. The Load Measuring Apparatus 10 of this alternate embodiment replaces the end plug 14, plug cover 15, shear washer 16 and shear nut 13 assembly with a single component cap member 13' which does not provide the safety function of the shear washer 16 but does provide the force transfer function of the prior-mentioned assembly. All other components of this alternate embodiment of FIG. 8 are as described with respect to the preferred embodiment.
Whereas the present invention has been described in detail with specific reference to preferred embodiments thereof, it will be understood that variations and modifications can be effected within the spirit and scope of the invention, as described before and as defined in the appended claims. | A load measuring apparatus is, in preferred embodiments, preassembled in a ready-to-use, portable assembly and comprises a load bearing body providing a deformable link between a shaft housing (such as a valve operator) and a shaft which moves relative to the housing, and which deformable, load bearing body functions as the support for a shaft engaging element of the invented device; and also comprises strain gauges measuring the deformation of the load bearing body, which deformation is related to the thrust of the shaft; load measuring apparatus operating in association with a signal conditioning device and display/recording device by which measurements are conveyed and interpreted; in the preferred embodiment, the load measuring apparatus includes an overload shear washer incorporated to prevent damage to the shaft housing by shearing away and allowing continued, unblocked movement of the shaft. | 5 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to a method of configuring a system comprising a moving screen of the type comprising a roller blind, shutter, garage door, projection screen, or analogous element that is driven by an actuator. Such an actuator generally comprises an electric motor powered under the control of an electronic unit. The electronic unit interacts with a control member that may be fixed, in which case control takes place in a wired mode, or portable, in which case control take place by radio or infrared. Such a control member is sometimes referred to as a “control point”. When control takes place over wires, it is often referred to as a “control box”, whereas when control takes place by radio or infrared, reference is often made to a “remote control”. Thus, actuating a button of the control member causes the actuator to execute an order. One button may cause the actuator to move in one direction, and another button may cause it to move in the opposite direction.
2. Brief Description of the Related Art
For reasons of comfort and/or safety, that type of system enables the opening of the screen to be controlled automatically. It is then necessary to program the stroke of the screen, and in particular its high and low end-of-stroke positions. Some actuators manage screen positioning by an electronic unit counting the number of revolutions performed and/or detecting a threshold motor torque, for example. Under such circumstances, a training stage is needed during which the electronic unit switches over to a mode that enables the parameters of the system to be defined. Those parameters identify the high and/or low end-of-stroke positions.
To switch over to training mode, a first solution consists in varying the power supply to the electronic unit, e.g. switching it off twice in succession within a determined period of time. That solution is not practical if a plurality of actuators share the same power supply and if it is not desired that all of them should switch over to training mode together. It is also known, for the same purpose, to connect a shunt between two phases of the motor for a determined duration. The shunt may be obtained by a special adjustment tool or by physically connecting together two terminals on the electronic card of the control point via a metal component. That solution requires a suitable tool to be used and requires the system to be dismantled in order to make the shunt connection.
In another approach, it is possible to press simultaneously on two of the buttons of the control member, for example the up and the down buttons, or the stop and the programming buttons. In itself, that operation does not cause the screen to move at all. It is then not clear whether the operation has been carried out properly. Furthermore, certain control members do not enable two buttons to be activated simultaneously or do not have a stop button or a program button. This is true in particular when renovating a system in which it is not necessarily desirable to change the control member(s) and/or to rewire the installation.
To solve this problem, WO-A-00/49262 describes a configuration method and system using control members having two buttons: on and off. To cause an electronic unit controlling an actuator to switch over to training mode, a sequence of button presses must be executed, each button needing to be pressed in a determined time. If the sequence is achieved, then the electronic unit switches over to training mode. With such a method and such a system, the order transmitted by a control member is always executed after a time delay in order to verify whether or not the user is beginning a sequence of presses for switching over to training mode. This time delay is undesirable in normal operation. Furthermore, it is not obvious how to tell whether the switchover to training mode had indeed taken place, since no movement results between the successive button presses.
EP-A-0 718 729 discloses causing a roller blind to perform a predetermined movement, such as down a little and then up, after a user has fully executed an operation seeking to cause the blind to switch over into programming mode. It is only after a processor unit has entered programming mode that the above-mentioned movement of the blind takes place, so that while entering a programming order, the user cannot be certain that the order is indeed correct. Furthermore, the panel moving down a little and then up is not necessarily representative of the programming order, which can lead to a certain amount of confusion for the user.
SUMMARY OF THE INVENTION
The invention provides a configuration for such a system that enables the above-mentioned drawbacks to be mitigated.
To this end, the invention relates to a method of configuring a system for driving a screen for closure, sun protection, or projection purposes, the system comprising: an actuator for driving the screen; at least one control member provided with at least one button; and an electronic unit suitable for controlling the actuator as a function of a control signal received from the control member; the method comprising a step of switching the electronic unit over to a training mode, on the basis of a predetermined series of control signals received by the control member, said series of signals being the result of executing a predetermined press sequence on at least one button of the control member. This method is characterized in that during execution of the predetermined press sequence, the electronic unit changes the state of the actuator as a function of each signal received from the control member.
By means of the invention, in order to cause the electronic unit to switch over to training mode, the user needs to execute a specific sequence of button presses on the control point. In the description below, the user may be a professional installer of a system that includes a moving screen, or any other person involved in adjusting such a system, including the end user. During this operation, each button activation causes the actuator to execute an order that gives rise to the actuator moving or ceasing to move, i.e. to it changing its state. In this way, the user can visually verify that the specific sequence is being performed by observing the movements and the stops of the screen, without it being necessary to wait until the predetermined press sequence has been fully executed. If the user makes a mistake while pressing the buttons, then this is obvious immediately, without it being necessary to wait in vain for the electronic unit to switch over to training mode. The user is thus informed in real time that the press sequence is being performed properly and that the electronic unit is going to switch over to training mode. In addition, since the state of the actuator is changed by the electronic unit as a function of the received signal, the movements of the screen can be representative of the press sequence implemented by the user, thus making visual checking easier compared with the configuration in which the movement performed by the screen is always the same.
Advantageously, during execution of the predetermined sequence, a press on a button of the control member causes the electronic unit to change the state of the actuator in the same manner as when the control member is used for controlling the drive system in normal operation. This makes it easier for the user to check visually while performing the predetermined press sequence.
In addition, the predetermined press sequence on the button(s) of the control member does not cause the screen to reach a particular position prior to switching over the electronic unit to training mode. As a result, the configuration operation is simple. The electronic unit can be caused to switch over to training regardless of the position of the screen.
When the control member is provided with a plurality of buttons, at least one signal resulting from pressing on one of its buttons during the predetermined sequence cannot not be taken into account by the electronic unit as forming part of the predetermined series of control signals that gives rise to the electronic unit switching over to training mode. A system having a plurality of control points that are not necessarily operated in the same way and that do not necessarily have the same number of buttons can thus have a uniform procedure for switching over to training mode.
The method of the invention may comprise the following successive steps:
a) the electronic unit processes signals received from at least one control member and causes the actuator to execute an order associated with an activated button; b) the electronic unit identifies the initial button of the predetermined press sequence; and c) the electronic unit compares the activated button with the initial button.
Advantageously, the electronic unit switches over to training mode when the result of the comparison in step c) is positive and once complete execution of the predetermined press sequence has been detected by the electronic unit.
If the result of the comparison in step c) is positive, the method may also comprise the following successive steps:
e) the electronic unit accesses a memory storing information relating to the predetermined press sequence; f) the electronic unit identifies the following button to be activated in the predetermined press sequence; g) on receiving a signal, the electronic unit causes the actuator to execute an order associated with the button that corresponds to the received signal on being activated; h) the electronic unit compares the activated button with the following button; and i) if the result of the comparison in step h) is positive, the electronic unit compares whether the following button identified during step f) matches the final button of the predetermined press sequence; with steps e) and f) being reproduced so long as the result of the comparison in step h) is positive and the result of the comparison in step i) is negative; and the electronic unit switches over to training mode when the result of the comparison of step i) is positive.
In addition, if the result of the comparison in one of steps c) or h) is negative, provision can be made for the electronic unit to pass to a waiting state from which it executes steps a) to c) on receiving a signal from a control member.
To avoid the user performing involuntary operations, it may be necessary for the specific sequence to be executed within a limited time period. Switching over to training mode thus depends on the specific press sequence being performed in a determined time period. For this purpose, the method comprises a step for verifying whether the duration of the execution of the predetermined press sequence is less than a threshold value, and if the result of this verification is negative, then the electronic unit passes to a waiting state from which it executes steps a) to c) on receiving a signal from a control member.
Alternatively, in order to reduce the risk of an involuntary switchover, the specific sequence may incorporate durations for which it is necessary to hold down the press buttons. Under such circumstances, the method comprises a step of verifying whether the duration of a button activation during the predetermined press sequence has a value greater than a first threshold value and less than a second threshold value, and if the result of this verification is negative, then the electronic unit passes to a waiting state from which it executes steps a) to c) on receiving a signal from a control member.
In addition to direct visual verification when executing the specific sequence, provision can be made for configuration information to be returned indicating that switchover to training mode has indeed taken place, i.e. that the step of the electronic unit switching over to training mode has indeed occurred. The user can then be sure that the system has switched over to training mode.
The specific sequence may be defined while in training mode, by a particular run of button presses. The user can thus personalize this sequence.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention can be better understood on reading the following description given purely by way of example and made with reference to the accompanying drawings, in which:
FIG. 1 is a diagrammatic view of a drive system with which the invention can be implemented;
FIG. 2 is flow chart showing a configuration method of the invention;
FIG. 3 is a fragment of a flow chart showing a variant of the FIG. 2 flow chart in which a first additional function is introduced; and
FIG. 4 is another fragment of a flow chart for another variant of the FIG. 2 flow chart, in which a second additional function is introduced.
DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 shows a tubular actuator 10 for driving a winder tube 2 on which at least one panel or screen 1 can be wound. The actuator 10 comprises an electric motor and gearbox assembly 11 connected to the winder tube via a connection that is not shown, and an electronic unit 12 controlling the power supply to the motor 11 . The electronic unit also incorporates a module 13 for detecting the ends of strokes of the panel, i.e. for detecting when the panel reaches determined positions. End-of-stroke detection can be obtained by various means such as detecting overtorque j measuring time, or counting a number of revolutions.
The electronic unit 12 is controlled by a wired control box 20 and by a portable remote control 30 . The communications means shown for the remote control is radio via antennas 15 and 31 . It would also be possible to use infrared communication between the remote control 30 and the unit 12 . The unit 12 could be controlled by only one member, i.e. only the box 20 or only the remote control 30 .
The control members 20 and 30 are provided with buttons 20 1 , 20 2 , 30 1 , 30 2 , 30 3 . When one of these buttons is pressed, an order is transmitted to the unit 12 and, from there, to the actuator 10 .
To raise the panel 1 it suffices to press on one of the up buttons 20 1 or 30 1 . When the button 20 1 is activated, the electronic unit 12 receives a signal S 1 via a line L 1 providing an electrical connection between the box 20 and the unit 12 . The unit 12 then processes the signal S 1 in order to power the motor 11 in such a manner as to implement the desired movement of the actuator. When the remote control button 30 1 is activated, the antenna 31 transmits a radio signal S′ 1 that is received by the antenna 15 and processed by the unit 12 like the signal S 1 . In the present example, when the user presses on one of the up buttons 20 1 or 30 1 , the motor 11 is powered by the unit 12 so as to drive the winder tube 2 in the direction of arrow F 1 , so that the panel 1 is then wound around the button tube 2 .
To issue a down instruction, the buttons to be activated are the buttons 20 2 and 30 2 , thereby causing down order signals S 2 or S′ 2 to be sent to the unit 12 , either over the line L 1 or by radio. The actuator 10 is then controlled by the unit 12 to turn the tube in the direction of arrow F 2 , thereby causing the panel 1 to be lowered.
To stop the movement, if the control member is fitted with a stop button, as is the remote control 30 with its button 30 3 , it suffices to activate this button to transmit a stop signal S′ 3 which is processed by the unit 12 to cease powering the motor 11 .
With a more basic control member, movement can be stopped differently. In a first configuration, the up or down movement of the actuator is obtained so long as the up button 20 1 or the down button 20 2 is pressed. Thus, as soon as the button is released, the screen 1 stops. In a second configuration, stopping is obtained by pressing on the button that corresponds to moving in the opposite direction. If the up button 20 1 or the down button 20 2 is pressed, that button remains active until it is deactivated by the user pressing on the other button, i.e. the down button 20 2 or the up button 20 1 .
In order to adjust the ends of the strokes, the electronic unit 12 needs to be switched into training mode. This change of mode is made possible when a specific or predetermined sequence of presses is applied to the control member 20 or 30 . This sequence is not necessarily exclusive, so it is possible for the electronic unit to respond to a plurality of specific sequences, or to some other means for causing it to switch over. Thus, for example, the electronic unit switches over to training mode if a first specific sequence is reproduced, or if a second specific sequence is reproduced, or if a programming button on the control member is pressed.
In the description below, the predetermined sequence S prog is said to be “specific” in the sense that it relates to a sequence of presses on the buttons suitable for causing the unit 12 to switch over to training mode. Informations relating to the specific sequence of presses to be performed in order to switch the unit 12 into training mode is stored in a memory 14 of the electronic unit 12 . For convenience of description, it is assumed below that the specific sequence of presses S prog is stored in the memory 14 . However, it is preferable for the specific sequence to be implanted in the program of a microcontroller that is mounted instead of the memory 14 and that has the function of controlling the actuator 10 . The description below refers to the memory 14 , but it should be understood that it could equally well refer to such a microcontroller. The electronic unit compares the signals it receives from the control member 20 or 30 with the sequence stored in its memory 14 . If the sequences match, then the unit switches over to training mode, otherwise it remains in utilization mode.
In the example shown, the electronic unit 12 is situated in the actuator 10 , however it could very well be situated outside the actuator, e.g. in the control member 20 or 30 .
FIG. 2 shows a configuration method enabling switchover of the unit 12 into training mode to be activated.
An initialization step INIT enables the specific sequence S prog of presses on the buttons to be stored or recorded in the memory 14 of the electronic unit. This recording stage may be performed by the manufacturer of the actuator 10 at the site of production. The specific sequence may also be defined directly in the program. It is therefore not necessarily configurable.
The specific sequence comprises a first button T i to be activated. To illustrate the method, the following sequence S prog has been selected: one pulse on the up button of the control member 20 or 30 , one pulse on the down button, and one pulse on the up button. T i thus corresponds to the up button 20 1 or 30 1 . Each pulse on a button causes a signal S 1 , S 2 , S′ 1 , S′ 2 or S′ 3 to be sent to the electronic unit 12 . The specific sequence can thus be considered in terms of signals received. In the present example, it may be S 1 , S 2 , S′ 1 , or S′ 1 , S′ 2 , S′ 1 , or a mixture of the signals. For convenience the sequence is described in terms of the buttons pressed, even if it is the signal that serves to identify execution of the sequence.
In a first step 100 , the user presses on a button T a of a control member.
In a second step 110 , the unit 12 processes the signal S 1 , S 2 , S′ 1 , S′ 2 , or S′ 3 received from the control member 20 or 30 and corresponding to the button T a so as to cause the actuator 10 to execute the order associated with the button T a . For example if T a is an up button 20 1 or 30 1 , then the actuator 10 is controlled by the unit 12 so that the tube 2 turns in the direction for winding up the panel 1 , in the direction of arrow F 1 .
In a third step 120 , the electronic unit 12 identifies in its memory 14 which button T i initializes the specific sequence S prog , and then it determines whether the button T a that has been activated corresponds to the initial button T i . If so, the method moves onto a fourth step 130 . Otherwise, the method reinitializes and the unit 12 waits for a new step 100 to occur. In the present example, pressing the up button serves to move on to step 130 .
Identifying button T i and comparing it with buttons T a and T i , as performed in step 120 , could also be performed in two distinct steps.
During step 130 , the electronic unit 12 reads the specific sequence S prog stored in the memory 14 .
In a fifth step 140 , following step 130 , the electronic unit identifies the following button T s that needs to be executed if the specific sequence S prog is reproduced. The following button T s is the button that comes after the previously-activated button T a in the specific sequence as recorded. In the present example, the button T a activated in step 110 corresponds to the initial button T i , i.e. the up button. The following button T s is thus the second button for activating in the sequence S prog , i.e. the down button.
In a sixth step 150 , the user presses on a new button T a .
In a seventh step 160 , the unit 12 processes the signal received from the control member in order to cause the actuator to execute the order associated with the button T a . For example, if T a is the down button, the tube 2 is driven in the direction for lowering the panel 1 .
In an eighth step 170 , the electronic unit verifies whether the button T a that has been activated corresponds to the following button T s as identified in step 140 . If so, the method moves onto a step 180 . Otherwise, the method reinitializes and the unit 12 waits for a new step 100 to occur.
In a ninth step 180 , the electronic unit identifies whether the following button T s identified in step 140 constitutes the last button T F of the sequence S prog . In other words, the unit 12 verifies whether there remains another button to be activated after the action in step 150 in order to comply with the specific sequence S prog as recorded. If so, the method moves onto a tenth step 190 . Otherwise, method returns to step 140 .
In the above-mentioned example, the user has pressed once on the up button and once on the down button. It now remains to press once more on the up button in order to terminate the specific sequence. The method thus moves to step 140 . During step 140 , T s now corresponds to the up button. If in step 150 the user does indeed activate the up button, then the sequence S prog will have been reproduced in full, and the unit will move on to step 190 after step 180 . In this tenth step 190 , the electronic unit switches over to training mode.
In a variant of the above-described method, step 130 may precede step 120 . If so, the button T i will be identified during step 130 and step 120 will merely comprise verifying that T a and T i match.
The orders executed by the actuator 10 during steps 110 and 160 correspond to orders for changing the state of the actuator. If the motor was stopped, a change of state is causing the actuator to move. If the motor was moving, a change of state is stopping it or causing it to move in the opposite direction. When the movement of the actuator continues so long as the button on the control point is activated, releasing the button and pressing again on the same button causes a change in the state of the actuator. This is because the motor stops when the button is released.
Provision can also be made for the specific sequence S prog to comprise only orders that cause the actuator to move. A stop order is then not taken into consideration.
In analogous manner, another implementation consists in not taking into consideration the activation of certain buttons. For example, S prog may correspond to three pulses on the up button. The stop button can then be ignored. Under such circumstances, the sequence: up/stop/up/stop/up reproduces the recorded sequence S prog . The electronic unit 12 then switches over to training mode on receiving this sequence.
In all of its variants, the method of the invention is independent of the position of the screen 1 . It is therefore not necessary for the screen to be taken to or to pass through any particular position for the unit 12 to switch into training mode in step 190 .
Preferably, the method incorporates a time delay making it possible to define a period during which the specific sequence must be executed. By way of example, the sequence must be reproduced within less than 6 seconds. This variant is shown in FIG. 3 .
In the variant of FIG. 3 , a step 135 , after the step 130 and before the step 140 , serves to enable the electronic unit 12 to trigger a time count Dt. In a later step 175 , after the step 170 and before the step 180 , a comparison is performed to see whether the button T s of the specific sequence was activated in step 160 before the end of a predetermined period ΔT, equal to 6 seconds in this example. If so, the method moves on to a step 180 . Otherwise, the method reinitializes and the unit 12 waits for a new step 100 to occur.
In a variant, the step 175 may be shifted to between the steps 180 and 190 . Under such circumstances, verification that the sequence S prog has indeed been performed within the prescribed period is performed solely at the end of the sequence.
It is also possible to insert a comparison identical to that of step 175 during a step that occurs after step 140 and before step 150 , having consequences analogous to those of step 175 .
In a variant, it is also possible to use a time delay to verify that the execution of the specific sequence has a duration that is greater than a predetermined value, e.g. equal to four seconds. Under such circumstances, the specific sequence must be performed over a duration lying in the range 4 seconds to 6 seconds.
Another implementation consists in integrating in the specific sequence, durations for holding down the buttons in the sequence to be reproduced. For example, when the specific sequence S prog is constituted by three successive presses for which each press needs to be performed in a time range lying between 100 milliseconds (ms) and 1 second (s), if the button is pressed once for a longer period, i.e. for more than one second, then the sequence has not been reproduced correctly and training mode is not activated. The unit 12 waits for a new step 100 to occur. In another approach, the verification steps 120 and 170 include verification that the duration for which the button T a is activated corresponds to a predetermined time interval, i.e. 100 ms to 1 s in this example. Generally, this constraint suffices to protect against fortuitous execution of the specific sequence in normal operation. For energy saving reasons, it is possible to take account solely of the duration for which a button is pressed in the specific sequence and not to take account of the total duration of the sequence. If the total duration of the sequence is taken into account, it is then necessary to power the control unit during periods when no buttons are pressed, so as to continue measuring time lapses, and that increases energy consumption.
At the end of the method, as shown in FIG. 4 , information can be returned in a step 185 in order to confirm to the user that the unit 12 has indeed switched over to training mode in step 190 . This return of information may be a specific movement of the screen, e.g. an up and down movement, switching on an indicator light, or momentarily activating a buzzer.
The specific sequence S prog may be modified by the manufacturer, the installer, or the user after the actuator 10 has left the factory. To do this, a new predetermined sequence S′ prog can be recorded following a specific programming operation, by activating the buttons with a selected sequence, while the electronic unit is already in training mode. The new sequence is then executed and recorded simultaneously in the memory 14 of the electronic unit.
The training mode of the unit 12 is not limited to adjusting the ends of strokes. Other parameters may also be adjusted in this mode.
The invention is described for use in controlling a roller blind. It can also be applied to controlling a shutter, and more generally any home automation screen for closure, sun protection, or projection purposes.
The technical characteristics of the various implementations described can be combined with one another within the ambit of the invention. | The method of switching an electronic unit of a movable screen for closures, sun protection devices and the like to a training mode on the basis of a predetermined series of control signals received from a control member, the series of signals being the result of executing a predetermined press sequence on at least one button of the control member. When the predetermined press sequence is executed, the electronic unit changes a state of an actuator for moving the screen as a function of at least one signal received from the control member, thus enabling the user to perceive that the predetermined press sequence has been recognized. | 6 |
[0001] This application claims the priority of German patent application 102004003196.716, filed Jan. 22, 2004, the disclosure of which is expressly incorporated by reference herein.
BACKGROUND AND SUMMARY OF THE INVENTION
[0002] This invention relates to a venting mechanism for a motor vehicle.
[0003] Such a venting mechanism is disclosed in European Patent EP 672 551 B1. This venting mechanism has an air channel bordered in the area of its outlet opening by a grating that completely covers the flow cross section. To provide the outflow cross section of the air channel with zones of diffuse outflow at one end and with a direct oncoming flow in the form of streams, the cover grating has nozzle-like openings of identical design distributed uniformly in the respective zones, said openings either becoming wider in the manner of the diffuser in the direction of flow or becoming narrower in the manner of jet nozzles. Diffuser openings and nozzle openings have approximately the same diameters and spacings. A choke is provided to regulate the air flow rate and distribution between two outlet areas. To achieve a uniform flow through the grating, the choke and grating are spaced a great distance apart and an insert of a nonwoven material is arranged in front of the grating.
[0004] The object of this invention is to create a venting mechanism having an air channel which has velocities of flow distributed uniformly over the flow cross section in particular when the available installation space is limited. In particular the flow resistance is to be minimized.
[0005] This object is achieved by a venting mechanism having a grating which covers the entire flow cross section of the air channel situated downstream in the immediate proximity of a flow obstacle, in particular in the wake of the obstacle. The grating has openings distributed uniformly over its area. The uneven distribution of openings results in the grating having different degrees of obstruction over its area. The different arrangement and/or design of the openings of the grating is associated with an equally heterogeneous design of the webs of the grating. The resulting differences in flow cross sections in the area of the grating result in the different degrees of obstruction.
[0006] The inventive grating equalizes the irregularity in flow caused by an upstream flow obstacle. The differences in flow are manifested in velocity of flow distributions and/or uneven distributions of the absolute pressure in the flow cross section. The openings in the grating are provided so that they form a reduced-flow area having a high degree of obstruction and a flow-through area having a low degree of obstruction. The equalization of the flow differences and/or pressure differences in the flow cross section is achieved by said uneven distribution of openings in the grating, whereby the design configuration of flow-through area and reduced-flow area is based on characteristic flow patterns in the wake of the flow obstacle. The reduced-flow area, which has a high degree of obstruction, is assigned to zones of a high absolute pressure, and the flow-through area having a low degree of obstruction is assigned to zones having a low absolute pressure of the flow cross section. An equalization of the flow in the cross section of the air channel is achieved downstream from the grating in the flow cross section.
[0007] Due to the arrangement of the grating in the immediate vicinity of the flow obstacle, an equalization of flow can be achieved while requiring only a small installation space. Due to the targeted design of the flow-through area and the reduced-flow area, no other equalization measures are required in contrast with the state of the art such as a nonwoven insert in front of the grating and a large travel length between the flow obstacle and the grating. This achieves an equalization of flow with a very low flow resistance and with a smaller required installation space than in the state of the art. In addition, due to the arrangement of the grating in the immediate vicinity of the flow obstacle in particular, it is possible to coordinate the arrangement of the flow-through area and the reduced-flow area with the wake of the flow obstacle.
[0008] In a special embodiment of the venting mechanism, in order to achieve different degrees of obstruction of the area of the grating with openings of the same size, which are especially advantageous, e.g., in a special cross-sectional shape and size, in terms of the noise generated, the openings of the grating are arranged with different spacings between them, thereby forming webs of different widths and thus flow-through areas and reduced-flow areas.
[0009] In a special embodiment of the venting mechanism, in order to be able to adjust the degree of obstruction with a low pressure drop in particular, openings of different cross-sectional areas and cross-sectional shapes are designed in the grating. The degree of obstruction of the grating can be adjusted by varying the size of the cross-sectional area of the openings themselves or, in the case of identical sizes of the cross-sectional areas, by varying the shape of the opening, such as the length/width ratios of the openings, for example. Through a corresponding adjustment of the grating, the noise generated by the venting mechanism can be improved.
[0010] A special embodiment of the venting mechanism is equipped with a grating which has different degrees of obstruction inside the reduced-flow area and/or the flow-through area. Openings of different designs and/or spaced different distances apart are provided within the aforementioned areas in the grating. The openings and/or the degree of obstruction may be varied continuously, i.e., steadily, e.g., a longitudinal extent in the area of the grating so that a smooth transition between the reduced-flow area and the flow-through area is possible, whereby the change in the degree of obstruction along the length because of the grating openings is only discretely variable, i.e., is quasi-steady. In the extreme case, however, one or more openings, e.g., slot-shaped openings with a different width of the flow-through area along the longitudinal extent in which it has a great width up to the reduced-flow area in which it has a small width. A plurality of design variants having the same function is conceivable.
[0011] A particular embodiment of the venting mechanism has a bend in the air channel upstream from the grating along a curve which in this case is effective as a flow obstacle. The reduced-flow area is assigned to the cross-sectional area of the air channel on the outside of the curve and/or the geometrically assigned surface area of the grating and the flow-through area is assigned to the cross-sectional area on the inside of the curve. Therefore, this equalizes the increase in velocity and/or pressure along the deflecting wall on the outside of the curve and in the flow cross section arranged in front of it and the low-pressure zone situated in the inside of the curve. Downstream from the grating there is a uniform flow through the flow cross section of the air channel.
[0012] In a special embodiment of the venting mechanism, an interference body is situated in the flow cross section of the air channel upstream from the grating. For equalization of the absolute pressure in the flow cross section, the flow-through area of the grating is assigned to the turbulent area of the interference body and the reduced-flow cross sections are assigned to the flow-through cross sections in addition to the interference body. Downstream from the grating there is a uniform flow of the flow cross section of the air channel.
[0013] In a special embodiment of the venting mechanism, the interference body is a shutoff valve. A reduced-flow area is assigned to an open slot of the shutoff valve and a flow-through area is assigned to an axis of the shutoff valve. Due to the associations of the reduced-flow area and the flow-through area, the turbulent area of the shutoff valve in the area of the pivot axis and the radial increase in velocity of flow are adapted to the open slots. The grating may also be designed based on a special and possibly particularly critical operating point or open angle of the valve through a structural arrangement and design of the openings.
[0014] Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] FIG. 1 shows a sectional diagram of an embodiment of the venting mechanism of the present invention along the longitudinal extent of the air channel, and
[0016] FIG. 2 shows a sectional diagram of the venting mechanism of FIG. 1 across the longitudinal extent of the air channel.
DETAILED DESCRIPTION
[0017] FIG. 1 shows a sectional diagram through a venting mechanism having an air channel 1 , which is bordered by its housing 1 . 1 across its longitudinal extent. The air channel 1 has air flowing through it along the arrow shown here. The remaining course of the air channel upstream is not shown in the drawing. The air channel 1 is bordered at the downstream end by the end opening 1 . 2 . Upstream from the end opening 1 . 2 , a grating 2 extending across the entire cross-sectional area of the air channel is arranged across the direction of flow. Due to the arrangement at a distance from the end opening, the grating is additionally covered by air baffles. The grating 2 has openings 2 . 1 and/or 2 . 3 and grating webs 2 . 2 and/or 2 . 4 . The openings 2 . 1 arranged adjacent to the channel wall (shown in cross section in the sectional diagram) have a smaller open cross section than do the openings arranged at a distance from the two sectional channel walls. Likewise, the webs 2 . 2 of the grating 2 arranged close to the sectional channel walls have a greater width than the webs 2 . 4 arranged at a distance from the two sectional channel walls. Due to this difference in the size of the design of the openings 2 . 1 and/or 2 . 3 and the difference in the width of the webs 2 . 2 and 2 . 4 , a reduced-flow area 1 . 3 is created in the lower immediate vicinity of the sectional channel wall 1 . 1 and a flow-through area 1 . 4 is created in the central area of the flow cross section which is at a distance from the two sectional wall areas.
[0018] Upstream from the grating 2 a shutoff valve 3 is arranged in the channel. The shutoff valve 3 is designed as a two-leg shutoff valve with a pivot axis 3 . 1 arranged at the center. To regulate the air flow in the air channel 1 , the shutoff valve 3 is pivotable about its central pivot axis 3 . 1 and can be moved from a closed position, in which it is in contact with both channel walls (shown in cross section in the sectional diagram) of the housing 1 . 1 , to an open position in which it is directed largely along the longitudinal extent of the air channel 1 .
[0019] FIG. 1 shows the shutoff valve 3 in a partially open position between the two end positions, i.e., the closed position on one end and the open position on the other end. Between the closing edge of the shutoff valve 3 and the wall area (shown in cross section in the sectional diagram) of the housing 1 . 1 , an open slot 3 . 2 is exposed on both sides. Due to the flow cross section of the open slots 3 . 2 , which is small in comparison with the full flow cross section of the air channel 1 , there is a great increase in velocity with a ray-like flow developing along the housing walls (shown in cross section in the diagram) of the housing 1 . 1 . In the central cross-sectional area of the flow cross section of the air channel 1 , a wake-like turbulent area is formed due to the coverage of the shutoff valve 3 in the area of the pivot axis 3 . 1 . Due to the increase in velocity along the wall, there is a great increase in the absolute pressure in the immediate vicinity of the wall directly downstream from the shutoff valve 3 in comparison with the absolute pressure in the central area of the cross-sectional flow downstream from the pivot axis 3 . 1 . The grating 2 arranged directly behind the shutoff valve 3 equalizes the flow, i.e., results in uniform velocities of flow over the flow cross section of the air channel 1 downstream from the grating 2 in particular in the cross section of the end opening 1 . 2 due to the great obstruction of the reduced-flow area 1 . 3 , i.e., the great flow resistance there, which is assigned to the area near the wall and thus to the wake of the open slot 3 . 2 and also due to the low velocity of flow of the flow-through area 1 . 4 which is assigned to the pivot axis 3 . 1 and/or the wake of the shutoff valve body. The direct structural assignment of the reduced-flow area 1 . 3 to the zone of a high absolute pressure and the direct assignment of the flow-through area 1 . 4 to the zone of a low absolute pressure make it possible to achieve a uniform flow in a very small installation space and with a low pressure drop.
[0020] FIG. 2 shows a sectional diagram across the longitudinal extent of the air channel 1 along the sectional line II-II in FIG. 1 . The air channel 1 has a housing 1 . 1 with an approximately rectangular cross section which is rounded in the corners. In the cross section of flow of the air channel 1 , the grating 2 is arranged over the entire cross-sectional area and is connected around the periphery to the wall areas of the housing 1 . 1 . Openings of different sizes, e.g., 2 . 1 and 2 . 3 , are provided in the surface of the grating 2 . These openings have different spacings and different cross-sectional areas. In the installed position of the upper and lower areas of the grating 2 near the wall, smaller openings 2 . 1 are provided and webs 2 . 2 having a wider area are provided there as well. In the central cross-sectional area at a distance from these two walls along the pivot axis 3 . 1 of the shutoff valve 3 arranged behind the grating, openings of a larger cross section 2 . 3 and webs 2 . 4 with a smaller width in the area of the grating 2 are provided. Rows of openings of a medium cross section are arranged between the rows of openings 2 . 1 of a small cross section and openings 2 . 3 of a large cross section. These form transitional areas between the reduced-flow area 3 . 1 formed by the small openings 2 . 1 and the wide webs 2 . 2 and the flow-through area 1 . 4 formed by the large openings 2 . 3 and the narrow webs 2 . 4 . The openings of the grating 2 are designed to be rectangular with straight edges and to improve the noise pattern they may advantageously be designed with a rounded cross-sectional contour and with rounded edges.
[0021] The foregoing disclosure has been set forth merely to illustrate the invention and is not intended to be limiting. Since modifications of the disclosed embodiments incorporating the spirit and substance of the invention may occur to persons skilled in the art, the invention should be construed to include everything within the scope of the appended claims and equivalents thereof. | A venting mechanism for a motor vehicle having an air channel and a grating which covers the flow cross section of the air channel, a flow obstacle being arranged upstream from the grating. In order to equalize the flow in the flow cross section with the lowest possible pressure drop, in particular when only a small installation space is available, the grating has an uneven arrangement of openings so that a high degree of obstruction is achieved in a reduced-flow area of the venting cross section and a low degree of obstruction is achieved in a flow-through area of the ventilation cross section. | 1 |
This application is a division of application Ser. No. 178,959, filed: Aug. 18, 1980, now abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention pertains to a method and articles for repairing and finishing gypsum wallboard and the like.
2. Description of the Prior Art
Gypsum or plaster wallboard is widely used in residential and commercial buildings for interior wall construction. Although gypsum wallboard is relatively inexpensive and easy to install in new interior building construction or remodeling it is easily damaged when impacted and is somewhat difficult to repair when cracked or punctured.
A variety of techniques and articles have been developed for repairing holes and cracks in gypsum wallboard. One well known method involves simply filling the hole with a backing of paper, rags or wire mesh and overlaying the backing with a patching compound. This method is generally undesirable because it is difficult to hold the backing material in place during repair operations. Moreover, the repaired portion of the wall usually remains structurally weaker than the undamaged wall portion.
Several inventions in the art of repair of wallboard have been developed which are generally characterized by mechanical devices which are foldable or collapsible so that they may be inserted through the hole to be repaired and then opened to form a backing surface to support the application of a patching compound. U.S. Pat. Nos. 2,598,194; 2,638,774; 2,997,416; 3,325,955; 3,583,122; 3,690,084; 3,874,505; and 4,100,712 disclose various types of devices which provide a backing for repairing a hole in wallboard. Not only are such devices generally somewhat complicated and expensive but the repair of a wall by filling the hole with patching compound is time consuming and requires two or more time spaced visits to the work site to complete the repair process.
It has also been proposed to provide prepared patches of various sizes which may be applied directly over the hole or indentation in the wallboard. U.S. Pat. No. 4,122,222 to Parker discloses a wallboard repair patch which is placed directly on the wallboard surface to cover the hole or other damage thereto. The repair patch disclosed in the patent to Parker comprises a layer of plaster or wallboard finishing compound laminated to a sheet backing member. The patch itself is not structurally rigid or strong enough to form the only means covering the hole, and, accordingly, a plug of wallboard material must be inserted in the hole and fixed therein before the patch is applied. In most instances the hole must first be dressed to accept a plug insert having a simple geometric shape for ease of insertion.
U.S. Pat. No. 4,135,017 to Hoffmann also discloses a repair patch adapted to be applied directly to the surface of the wallboard over the hole or damaged area. The patch disclosed in the Hoffmann patent is pre-coated with an adhesive for holding the patch in position over the damaged area of the wallboard.
The method and patches disclosed in the Hoffman and Parker patents do not provide for a repair which leaves the wall surface substantially flat and smooth. As is well known to those skilled in the art any interruption of the wallboard surface may show through certain wall coverings particularly if such coverings are provided with a gloss or otherwise highly reflective surface. The patches disclosed in the aforementioned patents as well as other prior art methods of wallboard surface preparation require repeated operations of applying wallboard joint or patching compound and sanding after drying in an effort to provide an uninterrupted surface. The method and articles provided for gypsum wallboard repair heretofore known have not successfully reduced the number of operations nor the time required to complete the wallboard repair process due to the need to make repeated visits to the repair worksite in order to provide a substantially smooth wall surface.
A further problem in the art of repair of gypsum wallboard or the like is concerned with the strength of the repaired section. In many instances the initial cause of the damage may be due to localized impacts which are likely to recur after repair. Accordingly, it is desirable that the repair patch be somewhat stronger than the original wall surface. In this regard, substantially all of the known patching methods and materials fail to provide the structural strength and rigidity desired together with the provision of a surface which will absorb some impact without causing cracking or flaking off of the surface coating.
The problems associated with known methods and materials for repairing gypsum wallboard or the like are substantially overcome by the method and articles provided by the present invention.
SUMMARY OF THE INVENTION
The present invention provides an improved method and articles for repairing gypsum wallboard and the like; wherein a hole or crack may be repaired with a patch element which will leave a substantially smooth uninterrupted wall surface, is structurally stronger and more resistant to damage from further impact than the original wall, and requires only one brief visit to the work site to complete the repair process.
The present invention contemplates a wallboard repair patch article which is easily applied to the damaged area of the wall, is structurally strong, and is economical to manufacture and use in the completion of the repair process.
The improved repair patch of the present invention comprises a metal plate preferably of rust preventative coated sheet steel which is bonded to a backing of paper or the like which overlaps the edges of the plate sufficiently to be used as a tape or backing which may be bonded to the wall surface. In a preferred form of the present invention the repair patch uses the same paper as is normally used as the facing paper in conventional gypsum wallboard.
One advantage of the repair patch of the present invention is that it is adapted to be used in conjunction with wallboard joint or finishing compound also known in the trade as "mud" and, accordingly, no special adhesives are required to be used on or in conjunction with the patch.
The wallboard repair patch of the present invention is advantageously provided with tangs or teeth which are conveniently formed on the metal plate portion of the patch and are operable to anchor the patch to the wall in position over the area to be repaired. The repair patch of the present invention is also provided with openings through the metal plate to allow for the wallboard joint compound to fill the openings and come into contact with the paper backing to increase the adhesion of the patch to the wallboard.
The wallboard repair patch of the present invention may be provided in a variety of configurations including preferred shapes for repair of elongated cracks, providing close fitting closures around piping or other objects which project from the wall surface, and for covering exterior corner damage or wall joints in new construction.
The present invention also provides an improved method of repairing wallboard wherein a substantially smooth surface is formed which may be completely co-planar with the original wall surface. In one preferred method according to the present invention a novel repair patch comprising a metal plate backed by a smooth paper backing is selected to cover the damaged area in its entirety. The patch is applied over the damaged area and the outline of the metal plate portion of the patch is cut into the paper surface of the wallboard. The patch is temporarily removed and the wallboard surface paper is then removed down to the plaster or gypsum core. A novel scraper, also according to the present invention, is used to remove the core material to a depth controlled by the length of a plurality of serrations or teeth on the scraper. Wallboard joint or finishing compound is then applied over the prepared recess as well as the surrounding area of the wall surface at least to cover an area as large as the area of the paper backing of the patch. The patch is then applied over the recess and pressed thereinto. A small amount of joint compound may then be applied around the edges of the paper backing to blend the paper smoothly into the surrounding wall surface. This embodiment of the method in accordance with the present invention is entirely suitable for walls which are to be textured on final finishing.
A second method for repairing gypsum wallboard in accordance with the present invention provides for removal of the wallboard paper down to the gypsum core to the outline of the metal plate portion of the patch, said method further provides for removal of only the face paper layer of the wallboard to the outline of the paper backing of the repair patch. Accordingly, after application of joint compound to the entire area of the wall which has been recessed, including the portion over which only the facing paper has been removed, the patch is applied to the recess and smoothed down with a trowel or putty knife in a conventional manner. The second embodiment of the method of wallboard repair in accordance with the present invention is therefore suitable for entirely smooth and untextured wall surfaces.
The present invention still further provides an improved template or cutter for determining the outline of the metal plate as well as the paper backing of the repair patch on the wall surface. The wallboard repair cutter according to the present invention is provided with serrations all along the exterior edges thereof which correspond to the outline of the paper backing of the repair patch. The cutter according to the present invention also includes serrations along the edges of an opening in the template which corresponds to the outline of the metal plate portion of the repair patch.
Accordingly the cutter of the present invention may be used in conjunction with the second embodiment of the method of repairing gypsum wallboard according to the present invention.
The present invention still further contemplates a novel kit made up of interrelated articles which may be used to practice the method of wallboard repair in accordance with the present invention. The wallboard repair kit in accordance with the present invention may include all of the elements necessary to carry out the novel method for repairing gypsum wallboard in accordance with the present invention.
As will be appreciated by those skilled in the art, upon reading the detailed description herein in conjunction with the drawings, the interrelated articles of the present invention are advantageously used to carry out the improved method for repairing wallboard, which method is faster and provides for a better finished appearance than heretofore known wallboard repair processes.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of an improved wallboard repair patch according to the present invention;
FIG. 2 is a cross-section of a portion of conventional gypsum wallboard or the like showing the application thereto of a repair patch in accordance with one method of repair according to the present invention;
FIG. 3 is a cross section of a portion of gypsum wallboard showing the application thereto of a repair patch in accordance with a second embodiment of a method of wallboard repair in accordance with the present invention;
FIG. 4 is a perspective view of an embodiment of the repair patch according to the present invention which is adapted for repair of elongated cracks in wallboard;
FIG. 5 is a perspective view of a further embodiment of a repair patch according to the present invention which is adapted to form closures around piping and the like;
FIG. 6 is a perspective view of yet another embodiment of a repair patch particularly adapted for application to exterior corners;
FIG. 7 is a perspective view of a cutter for use in practicing the method of wallboard repair according to the present invention;
FIG. 8 is a perspective view of an improved tool adapted to form a recess in the wallboard to a preferred depth; and,
FIG. 9 is a perspective view of a kit of interrelated articles which may be advantageously used to carry out the method of wallboard repair according to the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
In the description which follows like parts are marked throughout the specifications and drawings with the same reference numerals, respectively.
The drawings are not necessarily to scale and in some instances structural portions have been exaggerated in order to more clearly depict certain features of the invention.
Referring to FIG. 1 there is shown, in perspective, an improved wallboard repair article comprising a patch according to the present invention and generally designated by the numeral 10. The wallboard repair patch 10 is characterized by a rectangular metal plate 12 which is suitably bonded to a rectangular paper backing 14. The plate 12 includes a plurality of tangs or teeth 16 formed along each side of the plate near the intersections of the adjacent sides. The plate further includes a plurality of teeth 18 formed in a suitable square or rectangular pattern and spaced inwardly from the edges of the plate. The plate 12 is further characterized by a plurality of holes 20 which may be formed in a variety of patterns but are advantageously grouped in clusters of four near the corners of the plate. A preferred length or height or the teeth 16 and 20 as measured from the surface 21 of the plate is in the range of 2-6 mm. The plate 12 should be of a thickness which will resist bending and preferably be stronger than the original wall surface for use in repairing damage which is likely to recur. It has been determined that 22 to 28 gauge (i.e., approximately 0.780 mm to 0.390 mm thick) steel plate provides for a suitably strong repair patch. The aforementioned gauge numbers are in reference to U.S. Standard Sheet Metal Gauge designations. The plate 12 is also preferably made of rolled sheet steel which has been galvanized or provided with some other form of rust preventative treatment. It is comtemplated that the plate 12 can be finish formed in one stamping operation to not only cut out the plate to its final shape but also to form the teeth 16 and 18 and the holes 20.
The paper backing or cover 14 of the repair patch 10 is preferably formed of a smooth paper similar to the facing paper used in conventional gypsum wallboard. It is in fact preferred that the paper cover 14 be of the same type of paper as the conventional gypsum wallboard facing paper, such paper is of a thickness of approximately 0.4 mm. The paper cover 14 is desirably dimensioned to extend beyond the edges of the plate 12 approximately 25 mm on all sides. In order to form a smoother transition from the paper cover 14 to the surface of the wallboard in one preferred method of repair according to the present invention the cover is lightly sanded on one or both sides to approximately half of the width of the overlap of the cover with respect to the plate 12 as indicated by the dashed line 22 in FIG. 1. The cover 14 may be sanded on one or both sides to provide feathering or tapering of the thickness of the paper from the line 22 to the outer edges of the cover.
The cover 14 is preferably bonded to the plate 12 with a non water soluble contact cement of the type, for example, which is used to bond metal to cloth in such applications as automobile manufacturing. A preferred type of cement is one made by AIRSCO Adhesives Division under the part number 4830-10.
The repair patch 10 may be provided in a variety of shapes and sizes to provide for repairing various sized damaged areas and for use in finishing new wall construction.
Referring to FIG. 4 an alternate embodiment of the present invention comprising a patch particularly adapted for repairing stress cracks in wallboard is illustrated and designated by the numeral 24. The patch 24 includes an elongated metal plate portion 26 and a paper cover 28. The plate 26 includes teeth 30 formed along opposite longitudinal sides of the plate and spaced approximately 25 mm apart. Holes or openings 32 are also desirably formed in the plate 26 to permit joint compound to come into contact with the paper cover within the area delimited by the plate 26. The crack patch 24 is preferably formed so that the metal plate dimensions are approximately 50 mm wide by 750-1000 mm long. The width of overlap of the cover 28 around the edges of the metal plate 26 is desirably the same as for the patch 10 or approximately one-half the width of overlap used for the patch 10. The paper cover 28 may also be sanded to taper the thickness toward the outer edges from the dashed line 29. The materials used for the crack patch 24 may be the same as indicated for the patch 10. The crack patch 24 may be provided in a variety of lengths or cut to length as the crack to be repaired requires.
Another embodiment of a repair patch or wallboard finishing article in accordance with the present invention is shown in FIG. 5. The embodiment of FIG. 5 comprises a semi-circular patch element generally designated by the numeral 34. The patch 34 includes a semi-circular metal plate 36 which is bonded to a semi-circular paper cover 38. The plate 36 includes teeth 40 formed along the outer circumference, and a plurality of holes or openings 42 which provide for contact of the wallboard joint compound with the paper cover within the area delimited by the plate. The patch 34 also provides for an overlap of the paper cover with respect to the plate of approximately 25 mm except along the diametral edge 44 wherein the paper is even with the edge of the plate. The plate 36 includes a semi-circular opening 46, the size of which together with the size of the patch 34 may be varied. By using two patch elements 34 abutted against each other along their respective edges 44 suitable closures may be formed at locations where plumbing conduits project from the wall surface. The openings 46 may be dimensioned to form a snug fit around various standard conduit diameters to provide a suitable seal where conduits and the like must project through the wallboard. The materials used in the patch 34 and the method of fabrication of the plate 36 are preferably the same as for the embodiments described hereinabove and shown in the FIGS. 1 and 4. The cover 38 may be sanded to taper the thickness thereof from the dashed line 39 toward the outer peripheral edge of the cover.
Still another embodiment of a repair of finishing patch article in accordance with the present invention is shown in FIG. 6 of the drawings. Referring to FIG. 6 there is shown a finishing or repair patch generally designated by the numeral 48 which is particularly adapted for the finishing or repair of exterior corners or intersections. The corner patch 48 includes an elongated metal plate 50 bent relatively sharply along a central longitudinal line. The plate 50 may be provided with stamped teeth 52 and openings 54 both spaced apart along the opposite longitudinal sides of the plate. The functions of the teeth 52 and the openings 54 are the same as for the embodiments shown in FIGS. 1, 4 and 5. The corner patch 48 is also provided with a paper backing or cover 56 which is bonded to the plate 50 and overlaps the edges of the plate to the same degree as the embodiments in FIGS. 1 and 5. The thickness of the paper cover 56 may be tapered or feathered toward the outside edges thereof from the dashed line 59 in the same manner as described for the embodiments of FIGS. 1, 4 and 5. The materials used in the corner patch 48 may be the same as those previously described and used in the embodiments of FIGS. 1, 4 and 5 herein.
The wallboard repair and finishing articles herein described and shown in FIGS. 1, 4, 5 and 6 of the drawings are economical to manufacture, provide a stronger wallboard repair than may be obtained with prior art repair articles or processes, and are advantageously used in connection with an improved method of wallboard repair described hereinbelow.
Referring to FIGS. 2 and 3 of the drawings, a portion of a typical plaster wallboard is shown in cross section and generally designated by the numeral 60. The wallboard 60 may be of the type characterized by a suitable gypsum or other plaster type core 62 sandwiched between paper covering comprising a layer of a relatively coarse backing paper 64 on opposite sides of the core and a layer of a somewhat smoother facing paper 66 covering the coarse backing paper. The surface 68 is designated as the interior wall surface which may be finished by painting, texturing with a thin coat of plaster, or covered with a variety of solid wall coverings.
The general type of wallboard described herein is relatively easily holed os susceptible to surface damage. It is known to repair holes in wallboard such as the hole 70 shown in FIGS. 2 and 3 by filling the hole with one of a variety of finishing or repair compounds which air harden to form a plug in the hole which may be sanded smooth and flush with the surface 68. Generally speaking if the hole is more than approximately 12 mm in diameter some form of solid backing must usually be provided for covering the backside of the hole to hold the repair compound. Even with the assistance of a backing against the surface 72, FIGS. 2 and 3, large holes are difficult to repair because the compound will sag before hardening and also undergo shrinkage and cracking during the hardening process. Accordingly repeated trips to the worksite must be conducted to obtain a suitable repair which is not normally even as strong as the original wallboard structure. If damage to the wall is due to a cause which is likely to recur such as being impacted by a door knob or the like, the repair will be short lived. the wallboard repair illustrated in FIGS. 2 and 3 together with the improved method for making such a repair overcomes the problems associated with previous methods and articles used for wallboard repair and finishing.
In one embodiment of the method of wallboard repair in accordance with the present invention the hole 70 in the wallboard 60 is repaired by application of the patch 10, by way of example. The basic method of repair described herein may also be used in conjunction with the repair or finishing patches illustrated in FIGS. 4, 5 and 6 of the drawings.
Referring particularly to FIG. 2 the hole 70 is prepared for repair by cutting away any jagged or loose pieces of paper and or core material so that the intersection of the hole and the surface 68 is substantially rigid. An area of the surface 68 at least as large as the area of the paper cover 14 of the patch 10, and preferably larger by 10-25 mm in all directions, is sanded to remove paint or other surface coatings or materials from the wallboard facing paper. A patch such as the patch 10 is selected of suitable size such that the metal plate portion of the patch covers the hole 70 entirely and preferably extends beyond the edges of the hole at least 10 to 20 mm in all directions. The patch 10 is then centered over the hole as much as possible and pressed against the surface 68 forcing the teeth 16 and possibly also the teeth 18 into the wallboard. With the patch 10 in place over the hole or damaged area the paper cover 14 is carefully folded back so as not to crease the paper but sufficiently to permit scribing a line on or into the facing paper 66 around the edges of the metal plate 12.
After scribing a line defining the outline of the plate 12 the patch 10 is removed from the wallboard and a sharp knife is then used to cut into the surface 68 along the scribed line at least to the depth of the core 62.
Both layers 64 and 66 of the wallboard paper covering are then removed within the area bounded by the cut.
The practice of the improved method of the invention is enhanced by the use of a scraper illustrated in FIG. 8 of the drawings and generally designated by the numeral 80. The scraper 80 may be suitably formed of an elongated rectangular strip of sheet steel of a suitable thickness to resist bending in use and is characterized by a handle portion 82 and a head 84 formed by bending the strip as illustrated. Suitable teeth or serrations 86 are formed across the transverse end of the head 84. The teeth 86 are preferably formed to be of a length corresponding to the depth of a recess 88 to be formed in the core 60 of the wallboard as shown in FIGS. 2 and 3.
When the paper covering on the wallboard 60 has been removed within the area of the aforementioned cut any remaining paper that does not easily peel off the core may be removed along with some core material by use of the improved scraper 80. The length of the scraper teeth assist in controlling the depth of the recess 88.
After the recess 88 is formed and all loose core material is removed from the surface of the recess wallboard joint or finishing compound, designated by the numeral 89, may be liberally applied into the recess as well as to the surface 68 extending in all directions approximately 75 mm beyond the edges of the recess. The patch 10 is then reapplied over and into the recess with finger pressure and pushed into the recess so that the teeth 16 and 18 are firmly set into the core material. The metal plate portion 12 of the patch 10 now extends into the recess as illustrated in FIG. 2. A putty knife or trowel is then used to smooth the patch 10 into place by wiping excess joint compound across the entire exterior face of the paper covering 14 to seat the covering firmly against the facing paper 66 and also blending the very slight edge thickness of the paper cover 14 into the surface 68 of the wallboard. Additional joint compound may be applied to the surface 68 and the exterior surface of the paper covering 14 as required to blend the edges of the cover 14 into the existing wall. The feathered or tapered edges of the cover 14 minimize the requirement to blend the patch into the existing wall and form a substantially imperceptible transition from the existing wall to the exterior surface of the patch. After the joint compound has completely dried the repaired area may be further smoothed or finished with a light sanding operation.
The above described embodiment of the method of the present invention is preferred where an absolutely flat surface 68 is not required such as when a somewhat rough or textured finished wall surface is to be provided or when relatively heavy wall coverings are to be applied over the wall board. Even so, with the use of the smooth facing paper for the cover 14 on the patch 10 with the edges tapered, and the plate 12 recessed, a substantially planar wall surface is provided. The method above described in combination with the improved repair patch of the present invention also provides for a single operating visit to the worksite to produce a complete repair which is stronger than and will resist further damage better than the original wallboard structure.
For wall surfaces which must be absolutely flat a second embodiment of the improved method of wallboard repair according to the present invention may be carried out to produce a repaired area as shown in FIG. 3. In accordance with the method for repairing wallboard as shown by the repaired area in FIG. 3 the first steps in the method described above are carried out in the same manner up to and including the step of scribing the line around the metal plate 12. After scribing the line around the plate 12 the paper cover 14 is held flush against the wall surface 68 and a line is scribed around the outside edges of the cover. The patch 10 is then removed from the area to be repaired and a cut is made into the wallboard 60 along the aforementioned scribed line defining the outline of the metal plate. The aforementioned cut is made to a depth to assure removal of both layers of wallboard paper 64 and 66. The scraper 80 is then employed to remove any paper which does not readily peel off of the core after cutting the outline of the plate 12 and for removal of the core material 62 to form the recess 88.
Further according to the second embodiment of the method a cut is made along the scribed line defining the outline of the patch cover 14. The facing paper 66 is then removed within the area defined by the outline of the cover 14 and the recess 88 to form a second recess 90 having a depth equal to the thickness of the facing paper 66 which corresponds substantially to the thickness of the patch cover 14. The facing paper 66 is normally easily separated from the coarse backing paper layer 64.
Careful control of the depth of cut made in the scribed line defining the outline of the cover 14 will assist in removing only the facing paper layer 66. The process of cutting the outline of the metal plate 12 and the outline of the cover 14 may be enhanced by use of a novel template and cutter illustrated in FIG. 7 of the drawings and generally designated by the numeral 92. The cutter 92 is characterized by a sheet steel plate 93 of a suitable thickness to resist easy bending and is dimensioned to have an outer periphery 94 corresponding to the outline of the patch cover 14. Suitable teeth or serrations 95 are formed on the cutter 92 all around the periphery 94 and projecting perpendicular to the surface of the plate 93. The teeth 95 are preferably formed to have a depth corresponding to the thickness of the facing paper 66. The cutter 92 also includes an opening 98 formed in the plate 93 and having approximately the same dimensions as the outline of the plate 12 of the repair patch 10. The edges defining the opening 98 are also provided with teeth 100 similar to the teeth 96 but which may be longer or deeper to assure cutting completely through both layers of the paper backing of the wallboard.
The cutter 92 may be used in conjunction with the method for repairing wallboard disclosed herein by eliminating the steps of placing the patch over the hole and scribing the outline of the cover and plate on the wallboard. After the damaged area of the wallboard is trimmed as needed and sanded the cutter 92 is centered over the damaged area and pressed firmly into the wallboard to perform the cutting operations required for formation of the recesses 88 and 90. It will be appreciated by those skilled in the art that different sizes of cutters may be provided corresponding to the configurations of the repair patches. Moreover, the cutter may be of a size for cutting the outline of the repair patch metal plate portion only for practicing the first embodiment of the method of wallboard repair according to the present invention.
Referring the FIG. 9, the method of wallboard repair in accordance with the present invention may be practiced using a kit of interrelated parts as shown and generally designated by the numeral 102. The kit 102 may be mounted on a skin packaging card 104 or other form of packaging as desired. The kit 102 preferably includes one or more wallboard repair patches 10 and 24, shown for illustration purposes only, one or more cutters 92 corresponding to the most frequently used size of repair patch, for example, a scraper 80, and a container of patching or joint compound 106.
The kit 102 is advantageously used in carrying out the preferred method of wallboard repair and its composition and use make possible the practice of the superior method disclosed herein in an even more efficient manner.
The method of the present invention may be carried out also using the repair patch embodiment shown in FIGS. 4, 5 and 6 as will be appreciated by those skilled in the art. Moreover, other shapes and sizes of repair patches formed with the superior features of the repair patch 10 disclosed herein together with corresponding cutters similar to the cutter 92 may be provided without departing from the scope of the present invention. | Plaster core laminated wallboard is repaired or finished with a repair article comprising a substantially rigid steel plate having integral teeth forcibly insertable into the wallboard to hold the article in place over the damaged area, and a flexible cover portion formed of wallboard facing paper overlapping the edges of the plate and bonded thereto. The thickness of the paper cover portion may be tapered toward the outer edges thereof to form a smooth transition from the cover portion to the existing wallboard surface. Holes in the plate near the edges or corners thereof provide for increased contact of wallboard repair compound with the paper cover portion. The article may be formed in different configurations for covering plumbing openings, exterior corners and elongated stress cracks or seams.
The wallboard is repaired by cutting a recess into and through the paper surface lamination of said wallboard to the outline of the plate portion of the repair article. The facing paper layer of the wallboard may also be cut to the outline of the cover portion of the repair article to provide for recessing the cover portion also.
A repair kit is provided for performing the method of wallboard repair and comprising one or more repair articles, a cutting tool for cutting the outline of the repair article into the wallboard surface lamination, a scraper for forming a recess in the wallboard around the damaged area by removing core material to a predetermined depth and a portion of wallboard joint or finishing compound for adhesively bonding the repair articles to the wallboard. | 4 |
BACKGROUND
[0001] The present invention relates generally to sexual assistance or marital aid or therapeutic devices, and particularly to a miniature electrically powered massage vibrator encased in a resilient housing worn by a user for transferring vibration to a partner of the user.
[0002] Prior art miniature sexual aid or stimulating devices with a miniaturized massage vibrator generally have a mechanical switch which is manually actuated for the On/Off operation of the vibrator.
[0003] Existing designs of the switch face a problem that the On/Off switch is too small to easily operate. However, on the other hand the switch cannot be made in a larger size as this could affect the normal application and use of the vibrator.
[0004] Another problem faced by existing designs is the orientation of the switching direction relative to the device body. For example, in current vibrator devices, the switch is frequently positioned so as to be mistakenly actuated (switched off) by the motions of the massage action.
[0005] Another problem of existing designs relates to the availability or inclusion of a battery carrying means or device. That is, some vibrators do not have capability for battery changes. Certain other vibrators do not have a secure battery cover.
[0006] The present invention was therefore developed to provide for a miniature, electrically powered massage vibrator that overcomes one or more shortcomings of existing vibrator devices.
BRIEF SUMMARY OF THE INVENTION
[0007] A device of the present character is intended for transferring vibration to the female clitoris during intercourse. For example, embodiments of the presently described technology provide a miniature electrically powered massage vibrator that is encased in resilient housing and can be worn on the base of the penis for such purposes.
[0008] Among the advantages, benefits, features, goals and objectives relative to one or more embodiments of the present invention include the provision of a miniature (“mini”) electrically powered massage vibrator device (thus referred to as a “mini vibrator”) which of extreme compactness and miniature nature, which is capable of being worn on the male sex organ for stimulating the female clitoris during the act of sexual intercourse, as a sexual aid or for therapeutic purposes, for example. One or more embodiments of the device have a reduced overall dimension that can be effectively disposed at and provide vibrations to the sexual regions of partners. One or more embodiments of the device includes an effective on/off switch arrangement that, despite the miniaturized, very compact nature of the new device, is ergonomically convenient for operation of the device and is more difficult to be mistakenly actuated by movements of and/or use of the device during movements such as a massage action. One or more embodiments of the device includes an effective arrangement and means for changing one or more batteries of the device and which provides a more secure battery cover.
[0009] Briefly, according to one or more embodiments of the present invention there is provided a miniature electrically powered massage vibrator with an outermost shell slideably holding a vibrating body, that is, a vibration generator. The vibrating body includes a power source (of button-type battery cells, for example) for powering a motor of the vibration generator that is encased inside the body. The vibrating body also includes a power switching mechanism.
[0010] A sliding movement of the outermost shell relative to the vibrating body can provide the switching on/off functions of the electric power to the device. In a preferred application, this miniature vibrator can be encased in a soft resilient casing which is worn by a male user on the base of his sexual organ for providing stimulation to the organ of sexual partner of the user during intercourse.
DRAWINGS
[0011] FIG. 1 illustrates a perspective-type view of the massage device in accordance with an embodiment of the presently described invention.
[0012] FIG. 2 illustrates a perspective-type view of the massage device shown in FIG. 1 with the battery cover and batteries detached from the vibration body in accordance with an embodiment of the presently described invention.
[0013] FIG. 3 illustrates a perspective-type view of the massage device shown in FIG. 2 with the outermost shell detached from the vibrating body in accordance with an embodiment of the presently described invention.
[0014] FIG. 4 illustrates an exploded view of the components making up the device of FIG. 1 in accordance with an embodiment of the presently described invention.
[0015] FIG. 5 illustrates a perspective-type view of the components forming the power switching mechanism in accordance with an embodiment of the presently described invention.
[0016] Corresponding reference characters indicate corresponding parts in multiple figures of the drawings.
[0017] The foregoing summary, as well as the following detailed description of certain embodiments of the presently described technology, will be better understood when read in conjunction with the appended drawings. For the purpose of illustrating the presently described technology, certain embodiments are shown in the drawings. It should be understood, however, that the presently described technology is not limited to the arrangements and instrumentality shown in the attached drawings.
DESCRIPTION
[0018] A preferred embodiment of an embodiment of the presently described invention is presented, by way of example only, with reference to the accompanying drawings.
[0019] Referring to FIG. 1 , in one preferred embodiment of the present invention, powered miniature vibrator 1 comprises an outermost shell 2 slideably holding a vibrating body 3 with a battery cover unit 4 containing an electric motor, a battery chamber carrying button cell-type batteries and a power switching mechanism
[0020] Outmost shell 2 is a cylindrical hollow tube having a longitudinal slot 7 which is slideably engaged to key portions 5 and 13 on the surface of vibration body 3 . The engagement of slot 7 and such key portions provides a sliding guide for a longitudinal relative movement between outermost shell 2 and vibrating body 3 , and it also introduces a restriction of inhibiting and even preventing the rotational relative movement between the outmost shell and the vibrating body.
[0021] Cylindrical block 6 protrudes outwardly from the surface of vibrating body 3 . At a proximal end of outermost shell 2 there is a short curved slot 8 having two ends 8 a and 8 b . Cylindrical block 6 is engaged with the slot 8 . When outermost shell 2 is made to move relative to vibrating body 3 , block 6 has to overcome a larger friction at the middle portion of slot 8 due to its curved shape and the restriction of rotational relative movement between the outmost shell and the vibrating body, so that block 6 tends to stay at either end 8 a or end 8 b of the slot.
[0022] At the distal end of outermost shell 2 one or more holes 9 are disposed. For example, in an embodiment, two holes 9 of rectangular shape are disposed circumferentially at 180° apart. Each one of holes 9 is engaged with an arm 10 of a switch ring encased in the vibrating body 3 . Start/stop positions of block 6 at 8 a and 8 b in the slot respectively define on and off positions of the power switching system or arrangement. That is, block 6 can be moved between being at 8 a and being at 8 b . In an embodiment, when block 6 is at 8 a , the power switching system can be on and when block 6 is at 8 b , the system can be off (and vice-versa).
[0023] Referring to FIG. 2 , twisting battery cover 4 relative to vibrating body 3 and about the axis A-A unfastens the battery cover from the vibrating body, and button-type batteries 11 are loaded into or unloaded from the battery chamber of the vibrating body. A plurality of protrusions 3 a on the outer surface of the distal end of vibrating body 3 , and a plurality of protrusions 4 a on the surface of battery cover 4 provide an anti-slip gripping means. Various arrangements of protrusions, grooves or ribs are possible, and other gripping surfaces such as checking and surface roughening or regular or irregular surface treatments such as knurling or cross-hatching are among possible alternatives to enhance gripping of cover 4 .
[0024] Referring to FIG. 3 , an exploded or partly disassembled view, outmost shell 2 is shown detached from vibrating body 3 , whereas the battery cover 4 is detached from the vibrating body as well.
[0025] Referring to FIG. 4 , showing still further disassembly, hollow casing 12 has one opening 24 at the proximal end for accommodating an electric motor 17 , a plurality of protrusions 3 a on the outer surface of the distal end, and a key portion 13 on the outer surface. At the edge of the opening end of the casing 12 there one or more slots 14 apart for accommodating one or more arms 10 of switch ring 21 . For example, two slots 14 can be disposed circumferentially at 180° apart for accommodating one or more arms 10 of switch ring 21 . At the edge of the opening end of the casing 12 there are circular shoulder segments 34 for engaging the hole of cylindrical casing 16 at its distal end 25 . Further, at the edge of the opening end of the casing 12 and on the internal surface there is a recess 23 for accommodating contact blade or plate 35 .
[0026] The vibration generator formed by electric motor 17 has an eccentric mass 18 fixed on its shaft, an electric pole 19 defined by the outer surface of the motor, and another electric pole 20 disposed at the end of the motor. Switch ring 21 has a center hole slideably engaged with the external diameter of electric motor 17 , and an external flat face 22 for engaging with contact plate 35 . On the edge of distal end 25 of cylindrical casing 16 there one or more slots 15 for accommodating one or more arms 10 of switch ring 21 . For example, there can be two slots 15 disposed circumferentially at 180° apart for accommodating arms 10 of switch ring 21 . On the outer surface of the casing 16 is key portion 5 . On the outer surface of the casing 16 is cylindrical block 6 for engaging with slot 8 of outermost shell 2 . On the internal surface of the casing 16 there is a longitudinal key portion 26 for engaging with slot 28 of inner sleeve 30 , and on the other side of the internal surface there is a longitudinal recess 27 for accommodating contact plate 35 . In an embodiment, slot 28 extends from a distal end 32 of sleeve 30 to a proximal end 31 of sleeve 30 .
[0027] On the edge of the proximal end 31 of inner sleeve 30 there are two L-shape slots 29 disposed circumferentially at 180° apart for engaging with locking blocks 41 of battery cover 4 to lock the cover on to vibrating body 3 . Also, at the proximal end 31 of inner sleeve 30 and on the internal surface there is a recess 33 for securing the fixing end 35 a of contact plate 35 . The inner sleeve 30 is inserted, from the opening 44 , into the cylindrical casing 16 and fixed for providing the internal structural features. Contact spring assembly 45 is formed by a metallic blade or plate 37 with two locating tags 38 carrying a compression spring 39 . Spring assembly 45 is fixed with its locating tags 38 seated in recesses 42 on distal end 40 of battery cover 4 .
[0028] Referring to FIG. 5 , when battery cover 4 is locked on vibrating body 3 , spring assembly 45 is brought into effect to push battery set 11 toward electric motor 17 , i.e., in the distal direction, and so enables the negative pole (not shown) of the first battery to contact pole 20 of the motor, and at the same time a tag 38 of the assembly 45 is connected to the fixing end 35 a of the contact plate 35 . When switch ring 21 is moved in the direction B, it is equivalent to moving the block 6 towards the slot position 8 a ( FIG. 1 ), so that contact plate 35 then will bias into contact with pole 19 of the motor to close the power circuit and so to provide the switch-on function. Conversely, when switch ring 21 is moved in the proximal direction by the sleeve in the direction C it is equivalent to moving block 6 towards slot position 8 b ( FIG. 1 ), so that the switch ring 21 will push portion 35 b of contact plate 35 and move it away from pole 19 to open the power circuit and so to provide the switch-off function.
[0029] In view of the foregoing description of the present invention and possible variations of embodiments and methodology it will be seen that the several objects of the invention are achieved and other advantages are attained. As modifications could be made in the constructions and methodology herein described and illustrated without departing from the scope of the invention, all matter contained in the foregoing description or shown in the accompanying drawings shall be interpreted as illustrative rather than limiting. | A miniature electrically powered massage vibrator includes an outermost shell slideably holding a vibrating body, i.e., a vibration generator. The vibrating body contains a power source of button-type battery cells for powering a motor of the vibration generator encased inside the body, and a power switching mechanism. Sliding movement of the outermost shell relative to the vibrating body provides the switching on/off functions of the electric power. The massage vibrator is useful for sexual assistance or marital aid or therapeutic use. | 0 |
FIELD OF THE INVENTION
[0001] The present invention relates to an active noise cancelling headphone and particularly to a multi-loudspeaker active noise cancelling headphone that can provide stereo effect and improve ambient noise reduction.
BACKGROUND OF THE INVENTION
[0002] These days electronic products have become increasingly personalized and multifunctional. Activities such as listening music, watching movies and chatting via videos through electronic products are increasingly popular among many people. In order to get full and improved sound quality and avoid affecting other people most people would do the aforesaid activities by using headphones. However, the sound quality in the headphones could suffer due to too much ambient noise. To resolve this problem noise reduction headphones that can reduce ambient noise have been developed and increasingly accepted by consumers. At present the noise reduction techniques adopted in the electronic products mainly can be divided into active noise reduction and passive noise reduction.
[0003] The headphone of the conventional passive noise reduction technique aims to reduce external background noise. For instance, Taiwan patent No. M359891 entitled “Noise-proof headphone” discloses a noise-proof headphone which includes a hanging arm and a shell. The shell is located at two ends of the hanging arm and includes a shell cap and a shell body that form a housing space between them to hold a circuit board and a loudspeaker. The circuit board is formed in a shape mating the shell cap to couple tightly therewith so that the housing space is divided into a plurality of air chambers to isolate external noise.
[0004] Since the aforesaid noise-proof headphone has the circuit board and the shell cap tightly coupled together, a sound isolation wall is formed to isolate low frequency audio signals so that low frequency sound passing through the shell can be blocked by the sound isolation wall and the air chambers to reduce the external low frequency noise. However, in the event that the background sound is excessively large the sound in the headphone can still be affected, hence the aforesaid method of isolating the external background sound by blocking is limited in effectiveness.
[0005] Because of the efficacy deficiency of the passive noise reduction technique, most products in the market at present adopt the active noise reduction technique to reduce the external background sound in the headphone. For instance, U.S. Pat. No. 8,077,874 entitled “Active noise reduction microphone placing” discloses an active noise reduction microphone that has an error signal gone through a feedback process to combine with an audio in a signal processor, then is fed to a compensator which provides a phase input to an amplifier, then is fed to a sound module to combine with a noise; and through a microphone and an output amplifier, the error signal is formed which is combined with the audio through the feedback process. The above process is repeated cyclically to reduce the noise.
[0006] Through the sound module that generates the phase the noise can be offset and reduced, and through the feedback process the noise not being fully eliminated enters a next cycle of the noise reduction process. However, the noise is directly input to combine with the audio without going through any prior process but is reduced through a single loop, the noise reduction effect still leaves a lot to be desired. Moreover, it has merely one sound outlet that makes output sound monotonous and lower in quality. There is still room for improvement.
SUMMARY OF THE INVENTION
[0007] The primary object of the present invention is to improve the performance of noise reduction efficacy of the conventional headphone against the ambient noise and also resolve the problem of monotonous output sound that results in lower sound quality in listening music.
[0008] To achieve the foregoing object the present invention provides a multi-loudspeaker active noise cancelling headphone that can provide stereo effect and improve the performance of ambient noise reduction. The headphone is connected to and receives an audio signal for broadcasting. It comprises a microphone, a first filter, a first adder, an audio compensator, an active noise cancelling processor, an amplifier, a first loudspeaker, a second filter a second adder, a third filter and a second loudspeaker. The first filter and the second filter are electrically connected to the microphone. The first adder and the second adder are electrically and respectively connected to the first filter and the second filter. The audio compensator and the active noise cancelling processor are electrically connected to the first adder. The amplifier is electrically connected to the active noise cancelling processor. The first loudspeaker is electrically connected to the amplifier. The third filter is electrically connected to the second adder. The second loudspeaker is electrically connected to the third filter
[0009] The audio signal outputs music to the second adder that is processed and transformed by the third filter to match the characteristics of the second loudspeaker and also take into account of music quality to broadcast a first channel sound through the second loudspeaker.
[0010] The microphone receives an ambient noise from a space and outputs an ambient noise signal to the first filter which processes and transforms to a signal to match the characteristics of the first loudspeaker and take into account of music quality requirement, then is sent to the first adder, and joins a music compensation signal processed by the audio compensator, to be sent to the active noise cancelling processor to perform phase process to form a signal required for noise reduction that is sent the amplifier to be amplified and broadcast through the first loudspeaker to become a second channel sound.
[0011] The second channel sound is received by the microphone and input to the second filter, and goes through the second adder and enters the third filter for processing, then becomes a third channel sound broadcast via the second loudspeaker. The third channel sound has a signal phase reversed to that of the audio signal and the ambient noise signal, and is an auxiliary noise reduction signal that can improve the performance of noise reduction efficacy.
[0012] In short, the second channel sound offsets the ambient noise in the space, then is received by the microphone to output to the second filter for processing, and through the second loudspeaker to broadcast the third channel sound which is reversed in phase against the audio signal and the ambient noise signal, therefore becomes an auxiliary noise reduction signal that can improve the performance of noise reduction efficacy. After the audio signal is input to the headphone, the microphone receives the ambient noise to perform active noise reduction process to generate the third channel sound in a repeatedly cyclical process, thereby can achieve noise cancelling and stereo sound generation efficacy. The first channel sound output from the second loudspeaker and the audio signal are sound of the same phase, hence can improve music quality. The second channel sound output from the first loudspeaker has a phase re versed to that of the audio signal and the ambient noise signal, hence can reduce ambient noise without interfering the music to maintain desired sound quality. The third channel sound also has a phase reversed to that of the audio signal and the ambient noise signal, hence can reduce the noise around 4-10 db. The three channels of sound have time difference (delay) and phase difference among them, and through a repeatedly cyclical process in the space of earmuffs of the headphone, a three dimensional sound effect with a sense of depth can be generated, thus can provide improved music quality than the conventional active noise cancelling headphone.
[0013] The foregoing, as well as additional objects, features and advantages of the invention will be more readily apparent from the following detailed description, which proceeds with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] FIG. 1 is a system block diagram of an embodiment of the invention.
[0015] FIG. 2 is a system block diagram of another embodiment of the invention.
[0016] FIG. 3 is a measurement result according one embodiment of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0017] Please refer to FIG. 1 for the system block diagram of a first embodiment of the invention. It is for a multi-loudspeaker active noise cancelling headphone that can provide stereo effect and improve the performance of ambient noise reduction. It aims to connect to and output an audio signal 20 to the headphone for broadcasting. The audio signal 20 can be music, for instance. The headphone is collaborated with a pair of earmuffs 10 when in use during broadcasting of the audio signal 20 . The headphone comprises a microphone 30 , a first filter F 1 , a second filter F 2 , a first adder A 1 , a second adder A 2 , an audio compensator 40 , an active noise cancelling processor 50 , an amplifier 60 , a first loudspeaker L 1 , a third filter F 3 and a second loudspeaker L 2 .
[0018] The first filter F 1 and the second filter F 2 are electrically connected to the microphone 30 . The first adder A 1 and the second adder A 2 are electrically connected respectively to the first filter F 1 and the second filter F 2 . The audio compensator 40 and the active noise cancelling processor 50 are electrically connected to the first adder A 1 . The amplifier 60 is electrically connected to the active noise cancelling processor 50 . The first loudspeaker L 1 is electrically connected to the amplifier 60 . The third filter F 3 is electrically connected to the second adder A 2 . The second loudspeaker L 2 and is electrically connected to the third filter F 3 . The first filter, F 1 , the second filter F 2 and the third filter F 3 can be respectively a low pass filter, a high pass filter or a band pass filter.
[0019] The audio signal 20 outputs music to the second adder A 2 that is processed and transformed by the third filter F 3 to match the characteristics of the second loudspeaker L 2 and also take into account of music quality to broadcast a first channel sound S 1 through the second loudspeaker L 2 . The microphone 30 receives an ambient noise from a space and outputs an ambient noise signal to the first filter F 1 which processes and transforms to a signal to match the characteristics of the first loudspeaker L 1 and take into account of the music quality requirement, then is sent to the first adder A 1 , and joins a music compensation signal processed by the audio compensator 40 , to be sent to the active noise cancelling processor 50 to perform phase process to form a signal required for noise reduction, and sent to the amplifier 60 to be amplified and broadcast through the first loudspeaker L 1 to become a second channel sound S 2 . The second channel sound S 2 is received by the microphone 30 and input to the second filter F 2 , and goes through the second adder A 2 and enters the third filter F 3 for processing, then becomes a third channel sound S 3 broadcast via the second loudspeaker L 2 . The third channel sound S 3 has a signal phase reversed to that of the audio signal 20 and the ambient noise signal, and is an auxiliary noise reduction signal that can improve the performance of noise reduction efficacy.
[0020] The sources and function of various sounds in this embodiment are further elaborated as follows:
[0021] First, the audio signal 20 is sent to the second adder A 2 , and passes through the third filter F 3 , and output through the second loudspeaker L 2 to become the first channel sound S 1 in a positive phase.
[0022] Next, the audio signal 20 is sent to the audio compensator 40 and joins a signal processed via the first filter F 1 resulted from the ambient noise received by the microphone 30 that are processed via the first addition advice A 1 and the active noise cancelling processor 50 and the amplifier 60 to become the second channel sound S 2 in a reversed phase output via the first loudspeaker L 1 .
[0023] Finally, the microphone 30 further receives the second channel sound S 2 which passes through the second filter F 2 and outputs via the second loudspeaker L 2 to become the third channel sound S 3 in the reversed phase.
[0024] In this embodiment the three channels of sound have phase differences and time differences, and quickly and cyclically and consecutively appear in the earmuffs 10 to form a three dimensional sound effect with a sense of depth, therefore can generate improved sound effect and reduce noise.
[0025] Please refer to FIG. 2 for the system block diagram of a second embodiment of the invention. The multi-loudspeaker active noise cancelling headphone in this embodiment further includes a third addition deice A 3 , a third loudspeaker L 3 , a fourth filter F 4 and a fifth filter F 5 . The third adder A 3 is connected to the audio signal 20 . The fourth filter F 4 bridges the microphone 30 and the third adder A 3 . The fifth filter F 5 is connected to the third adder A 3 . The third loudspeaker L 3 is connected to the fifth filter F 5 . The fourth filter F 4 and the fifth filter F 5 can be respectively a low pass filter, a high pass filter or a band pass filter.
[0026] When in use the audio signal 20 outputs music to the third adder A 3 , and processed and transformed by the fifth filter F 5 to match the characteristics of the third loudspeaker L 3 and also take into account of music quality requirement to become a fourth channel sound S 4 broadcast via the third loudspeaker L 3 . In addition, the third loudspeaker L 3 also can further broadcast a fifth channel sound S 5 which also is an auxiliary noise reduction signal with a phase reversed to that of the audio signal 20 . Its generation process is same as the third channel sound S 3 previously discussed. Aside from the aforesaid embodiments the active noise cancelling headphone can also include more sets of loudspeakers or microphones.
[0027] As a conclusion, according to the invention the second channel sound offsets the ambient noise in the space, the microphone receives the second channel sound and outputs to the second filter for processing then broadcasts the third channel sound through the second loudspeaker, the third channel sound has a phase reversed to that of the audio signal and the ambient noise signal, hence can enhance noise reduction efficacy and also serves as an auxiliary noise reduction signal. From the audio signal being input to the headphone, the microphone receives the ambient noise to actively process noise reduction until generation of the third channel sound, and a repeatedly cyclical process is performed to achieve noise reduction effect. The first channel sound output from the second loudspeaker has the phase same as that of the audio signal, hence can improve music sound quality. The second channel sound output from the first loudspeaker has the phase reversed to that of the audio signal and the ambient noise signal, hence can reduce the ambient noise to avoid the music from being interfered by the ambient noise and maintain desired sound quality. The third channel sound has a phase reversed to that of the audio signal, hence can reduce the noise around 4-10 db, please refer to FIG. 3 . Those three channel sounds have time differences (delay) and phase differences among them, and repeatedly circulate in the space of the earmuffs to form a three dimensional sound effect with a sense of depth, thus can provide better quality of music than the noise reduction effect of the conventional active noise cancelling headphone, and provide significant improvements over the conventional techniques.
[0028] While the preferred embodiments of the invention have been set forth for the purpose of disclosure, they are not the limitation of the invention, modifications of the disclosed embodiments of the invention as well as other embodiments thereof may occur to those skilled in the art. Accordingly, the appended claims are intended to cover all embodiments which do not depart from the spirit and scope of the invention. | A multi-loudspeaker active noise cancelling headphone that can provide stereo effect and improve the performance of ambient noise reduction employs an active noise reduction circuit to collaborate with a plurality of speakers and a design to generate a multilayer phase difference feedback audio signal in the earmuffs of the headphone to improve the performance of noise reduction efficacy and generate stereo effect for music so that through the speakers of a lower cost and in a medium quality, and individual filters and signal compensation music with spatial sense and a sense of depth can be generated. | 6 |
FIELD OF THE INVENTION
The present invention relates to oil pump mechanisms for internal combustion engines, and more particularly to a pre-combustion oil pump mechanism for use with large capacity diesel engines.
DISCUSSION OF THE TECHNICAL PROBLEM
The bearing surfaces in diesel engines are subjected to extreme loads because of the relatively high compression ratios necessary to effect combustion. Recently, the life expectancy of large capacity diesel engines such as are used in massive earth moving equipment has been deteriorating. This condition requires more frequent and expensive overhaul work to keep the engine operational. During such overhauls, it has been regularly observed that the crankshaft bearings are exhausted long before expected, even though they were properly installed and the oil supply system was operating as designed.
A variety of approaches have been previously attempted to alleviate this problem, one such approach being exemplified by U.S. Pat. Nos. 3,583,525; 3,583,527; 3,722,623; 3,917,027; 4,061,204; 4,094,293; 4,112,910; 4,157,744; and 4,199,950. These patents generally teach that the problem relates to a lack of lubrication at start-up, and disclose systems having an auxiliary oil accumulator which through appropriate valving bleed off and store a portion of the oil supply during normal engine operation and release it under pressure to the engine prior to or at the time of the next restart. This approach is limited, however, because large capacity diesel engines often require the pumping of up to five gallons of oil before normal operating oil pressures are attained at the initiation of engine operation. While the release of a lesser quantity of oil from an auxiliary oil accumulator might yield some benefit, there would still remain a period during which the engine was cycling prior to the time that full lubrication was provided the moving parts. Because space is already at a premium in engine compartments, it is unacceptable to include an auxiliary oil accumulator having a sufficiently large volume, and even if it were practical, use of such a large volume accumulator would tend to create large variations in the oil supply of the engine. Finally, inclusion of a pressurized oil reservoir within a hot engine compartment presents an unacceptable safety hazard due to the possibility of a rupture and spray of flammable liquid thereover.
Another approach is exemplified by U.S. Pat. Nos. 4,058,981 and 4,126,997, which disclose that inadequate start-up lubrication is the cause of the problem and teach a valve system which initially routes engine oil to more critical engine components such as the turbocharger and crankshaft bearings upon start-up, and thereafter to less critical engine components. This approach is beneficial, but since it does not become operative until engine parts begin relative movement, premature wear of critical engine elements is still a problem.
Another approach, exemplified by U.S. Pat. No. 3,045,420, involves the use of a plurality of oil pumps, each supplying oil to separate engine lubrication systems. The pump which supplies oil to the turbocharger unit of the engine is actuated prior to combustion, continues during engine operation, and continues to operate for a brief period after engine shutdown to protect the relatively sensitive high speed turbocharger bearings. This system may be beneficial in extending the turbocharger life expectancy, but it does not protect other vital engine components, it introduces substantial complexity into the lubrication system of the engine, and failure of the turbocharges pump would lead to turbocharger failure within seconds.
Finally, maufacturers of internal combustion engines are known to attempt to minimize the problem by incorporating relatively large capacity oil pumps in the lubricating system in order to minimize the period between initial combustion and when engine oil pressure reaches its normal operating level. This approach has not had the desired result of reducing wear and it introduces unnecessary weight, size and expense to the engine assembly.
SUMMARY OF THE INVENTION
It has been found that the extensive and premature wear of large capacity engines is due to a combination of factors, including inadequate start-up lubrication. A significant factor in premature wear was found to be the length of time the engine is not used and the lubricity of the oil. Newer high lubricity oils increase the fuel economy of the engine, but they also tend to exacerbate the wear when engines are not operated for periods of time. Such oils tend to leave a smaller measure of residual oil on bearing surfaces when an engine is not in use, and as a result, bearings are left relatively unlubricated during the initial start-up period. Therefore the present invention provides a relatively simple and effective mechanism to extend the life of the bearing surfaces of an internal combustion engine, by assuring that an adequate oil supply is provided to the bearing surfaces before any relative movement of engine parts occurs.
In the conventional diesel engine, the oil pump mechanism is driven by gears from the crankshaft. Thus, oil is not directly provided to engine parts until after such parts have begun moving. Depending upon the size of the engine and the capacity of the pumping mechanism, full oil pressure is normally not obtained in the system for five or more seconds after cranking begins. Only residual oil remaining on the bearing surfaces from the previous operation provides lubrication and protection until a new supply of oil is provided by the pump.
In the practice of the present invention, oil is pumped within the engine passageways prior to cranking for a period sufficient to provide an operational oil pressure level before any engine parts begin to move. In this manner, all bearing surfaces are fully lubricated in advance of their load-bearing operation and life expectancy is substantially increased.
Although not limiting to the invention, this result may be accomplished by providing a supplemental oil pump which is conveniently driven from the starter motor armature shaft of the diesel engine. When the starter switch of the diesel engine is moved to its heat position to activate the glow plugs, an electrical impulse is also provided to initiate the rotation of the starter motor armature shaft to drive the supplemental oil pump, thereby bringing oil pressure up to operational levels while the operator waits to initiate cranking. When the starter motor clutch is actuated to turn the crankshaft to initiate combustion, both the main and supplemental oil pumps become operative. As the starter motor automatically disengages and is de-energized upon combustion, the supplemental oil pump stops. A main oil pump that is smaller and less expensive than normally utilized is sufficient to maintain the already-established oil pressure.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a side view in partially schematic form of a diesel engine including features of the present invention, with portions broken away or not shown for purposes of clarity.
FIG. 2 is a sectional side view of a starter and pre-ignition oil pump mechanism useful with the diesel engine shown in FIG. 1, incorporating features of the present invention.
FIG. 3 is a schematic diagram of the electrical system useful with the mechanisms shown in FIGS. 1 and 2, incorporating features of the present invention.
FIG. 4 is an exploded perspective view of an alternative supplemental oil pump useful in the practice of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
With reference to FIG. 1, there is shown a diesel engine 10 having portions removed and/or broken away to better illustrate the lubrication system thereof. Generally, the lubrication system includes a main oil pump 20 which is mechanically driven from the crankshaft 22 of engine 10. When actuated by rotation of crankshaft 22, main oil pump 20 draws oil from a sump 24 through a screening element 26 and distributes it under pressure through a plurality of conduits 28 to the engine's crankshaft bearings 30, to the turbocharger unit 32, to the valve train assembly 34, to the pistons 36, to and through a filtering assembly 38, and to other engine components requiring lubrication. As taught in U.S. Pat. Nos. 4,058,981 and 4,126,997, valving (not shown) may be included within the lubrication system to control the sequence in which oil is provided to the various engine components. As discussed before, main oil pump 20 is not actuated until crankshaft 22 begins to rotate due to the operation of an electromechanical starter assembly 40. Because a significant time period, e.g., five seconds, lapses before the main oil pump 20 is able to achieve normal operating oil pressure in the lubrication system, vital engine components may move through a large number of cycles with inadequate lubrication, resulting in undesirably high wear and premature failure.
In the practice of the present invention there is conveniently provided a pre-combustion lubrication system which operates prior to crankshaft rotation to achieve normal operating oil pressure before engine components begin relative motion. Although not limiting to the invention, the pre-combustion lubrication system according to the present invention preferably includes a supplemental oil pump 42 which is operatively connected to starter assembly 40. With particular reference to FIGS. 2 and 3, there is shown a mechanically driven gear-type oil pump 42 having an elongated drive shaft 43, and gears 44 and 45. Oil Pump 42 communicates with the engine lubrication system through an oil inlet line 46, an oil output line 47, and a check valve 48.
Starter assembly 40 may be conventional in configuration and includes a D.C. motor assembly 50 having an armature shaft 52 extending therethrough. Armature shaft 52 supports a starter gear 54 adjacent one end which engages flywhell 23 to rotatably drive crankshaft 22 when actuated, and a bendix drive mechanism 56 controls the axial movement of the starter gear 54 to engage and disengage it from the flywheel 23. According to the present invention, drive shaft 43 of oil pump 42 may be connected to the armature shaft 52 of starter motor 40 opposite starter gear 54 in any convenient manner so that the two shafts rotate together. Although not so shown in FIG. 2, oil pump 42 and starter motor 40 may be conveniently incorporated within a single housing to form an integral unit.
With reference to FIG. 3, a schematic diagram illustrates a preferred electrical configuration useful in the practice of the present invention with large capacity diesel engines.
The electrical system includes a pair of 12 volt batteries 58, a three position starter switch assembly 60, a plurality of glow plugs 62, a first solenoid 64 and a second solenoid 66 electrically communicating with starter assembly 40, and a disconnect switch 68.
With reference to FIGS. 2 and 3, in a typical prior art diesel electrical system, the disconnect switch 68 serves to disconnect the batteries 58 from the remainder of the electrical system. The three position starter switch assembly 60 has an off position, a heat position, and a cranking position. In the off position, as would be expected, the electrical system of the engine is inoperative. In the heat position, the glow plugs 62 are electrically activated to provide heat to the cylinders to facilitate initial combustion, but the starter assembly 40 remains electrically inactivated. In the cranking position, 24 volts of electrical energy are provided from batteries 58 to first solenoid 64 adjacent starter assembly 40. First solenoid 64 energizes the electrical motor of starter assembly 40 to initiate rotation of armature shaft 52 while at the same time it energizes bendix drive mechanism 56 to engage starter gear 54 with flywheel 23. When the engine starts, starter gear 54 automatically disengages from flywheel 23 and first solenoid 64 may be deactivated to electrically disconnect the starter assembly 40.
With this general appreciation of conventional diesel engine electrical systems, and with continued reference to FIGS. 2 and 3, the following discussion should provide an understanding of the operation and benefits of the present invention. According to the present invention the three position starter switch assembly 60 has an off position, a heat and pump position, and a cranking position. The off position renders the electrical system of the engine inoperative. In the heat and pump position, the glow plugs 62 are activated with 24 volts of electrical energy to provide heat to the cylinders, but unlike in the conventional diesel electrical system, the starter assembly 40 is also electrically energized in a novel and beneficial manner. In particular, the present invention includes second solenoid 66 which energizes the electrical motor 50 of starter assembly 40 when the switch assembly 60 is in the heat and pump position, but does not energize the bendix drive mechanism 56 to engage the starter gear 54 with flywheel 23. Through this arrangement the rotatable shaft 52 of the starter assembly 40 may be driven to rotate the drive shaft 43 of oil pump 42 to initiate the pumping of oil therethrough, prior to the cranking of the engine. The oil pump 42 remains energized during the entire preheat period and is able to achieve normal operating oil pressures throughout the engine prior to combustion, thereby assuring that the movable engine parts are lubricated during their initial cyclings.
When the glow plugs 62 have provided sufficient heat for initial combustion, the switch assembly 60 is moved to its cranking position, thereby deactivating second solenoid 66 and glow plugs 62, and activating first solenoid 64. First solenoid 64 reactivates the electric motor 50 of starter assembly 40 to rotate armature shaft 52 and also energizes bendix mechanism 56 to urge starter gear 54 into engagement with flywheel 23 to crank the engine.
During the cranking portion of the starting sequence, oil pump 42 is operatively driven from the armature shaft 52 of starter assembly 40, while main oil pump 20 is operatively driven by the rotation of crankshaft 22. Thus, during this critical period of engine operation both oil pumps 42 and 20 contribute to assure that normal operating oil pressures are achieved and maintained. This feature of the invention eliminates the need for engine manufacturers to incorporate larger than necessary main oil pumps in their diesel engines to assure that oil pressure reaches normal operating levels quickly after combustion begins.
Although not limiting to the invention, and with continued reference to FIG. 3, it is preferred that when the switch assembly 60 is in its heat and pump position, second solenoid 66, and accordingly starter assembly 40, are energized with only 12 volts of electrical energy from batteries 58. This may be effected by electrically connecting second solenoid 66 to one of batteries 58, or more as preferably shown in FIG. 3, by including an appropriate resistor in series with second solenoid 66. This feature of the invention provides at least two benefits; it conserves electrical energy in the batteries 58 which may later be needed for cranking, and it reduces the rotational speed of armature shaft 52 during the heat and pump portion of the starting sequence. As can be appreciated, the starter assembly 40 is able to drive an appropriately selected oil pump 42 with sufficient torque to achieve normal operating oil pressures in the engine prior to combustion even when it is only energized by 12 volts of electrical energy because during the heat and pump portion of the starting sequence it is not simultaneously cranking the engine. As shown in FIG. 2, gear-type oil pump 42 may be selected for use with the present invention. Alternatively, as shown in FIG. 4, a Model 601-1055 rotor-type oil pump available from the Balkamp Company of Indianapolis, Ind. has been found to operate satisfactorily to achieve normal operating oil pressures prior to combustion when driven at the rate of about 1200 r.p.m. by armature shaft 52.
When the switch assembly 60 is moved from the heat and pump position to the cranking positon, there may be a very brief period during which the starter assembly 40 is not electrically powered. The drag of the oil pump 42 during this brief period of transition preferably is sufficient to slow the rotation of armature shaft 52 to thereby facilitate the meshing of starter gear 54 with flywheel 23 when starter assembly 40 is reactivated with 24 volts of electrical energy. Thus, this feature of the invention eliminates the need for more elaborate clutching assemblies which might otherwise be needed if the starter assembly 40 was energized with 24 volts during both the heat and pump and the cranking portion of the starting sequence.
When the engine starts, the starter assembly 40 automatically disengages from the flywheel 23 and may be de-energized with switch assembly 60, thereby deactivating oil pump 42. Thenceforth, the main oil pump 20 need only maintain the oil pressures previously generated by the oil pump 42 during the heat and pump portion, and by both oil pumps 42 and 20 during the cranking portion of the starting sequence. Check valve 48 is mounted on the engine adjacent outlet line 47 to present oil backflow while oil pump 42 is inoperative, to prevent oil flow from spinning starter assembly 40 during normal engine operation.
As an additional benefit, practice of the present invention is virtually a failsafe system, because a failure of the supplemental oil pump 42 would not render the engine inoperative, thereby avoiding costly down-time for the equipment. Likewise, because the supplemental oil pump 42 pumps oil throgh the filtering assembly 38 before the oil enters the engine, failure of supplemental oil pump 42 would not introduce damaging particles into the engine.
While the present invention has been principally described in relation to large scale diesel engines where it is particularly beneficial, it is recognized that the invention is also useful in a wide variety of other types of internal combustion engines. For example, use of the invention in automotive applications is contemplated, both in diesel and in conventionally sparked engines. In the latter group of engines, there has been designed an auxiliary, starter-driven oil pump which provides pre-combustion lubrication controlled by a time-delay ignition switch, and which is as small in size as a conventional pocket watch. Accordingly, the present invention is not intended to be limited in scope by the description of the preferred embodiment provided above, but rather, only by the claims which follow. | An internal combustion engine is provided with an oil pumping system operatively driven from the starter motor which generates normal operating oil pressure prior to combustion. The starter motor is energized with a first, lower level of electrical energy during its precombustion oiling operation and a second, higher level of electrical energy during its engine-cranking operation to conserve electrical energy and facilitate meshing between the starter gear and the engine flywheel. | 5 |
CROSS REFERENCES TO RELATED APPLICATIONS
[0001] The present application claims the benefit of U.S. Provisional Application No. 61/153,420, filed Feb. 18, 2009, which is hereby incorporated by reference in its entirety.
BACKGROUND OF THE INVENTION
[0002] This disclosure is related to an integrated portable unit for providing electricity, air-conditioning and heating.
BRIEF SUMMARY
[0003] Disclosed is an integrated unit arranged and/or packaged on a vehicle for providing electricity, air-conditioning and heating to a space or location which is remote from the vehicle. The unit includes an electric generator system, a ventilation system, a refrigeration cycle system powered by the electric generator system, a heater that is also powered by the electric generator system and electrical outlets that are also powered by the electric generator.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0004] FIG. 1 is a system diagram of one embodiment of an integrated portable unit for providing electricity, air-conditioning and heating.
[0005] FIG. 2 is a left side elevational view of a trailer embodying one version of an integrated portable unit for providing electricity, air-conditioning and heating.
[0006] FIG. 3 is a right side elevational view of the trailer of FIG. 2 .
[0007] FIG. 4 is a front elevational view of the trailer of FIG. 2 .
[0008] FIG. 5 is a rear elevational view of the trailer of FIG. 2 .
[0009] FIG. 6 is a rear elevational view of the trailer of FIG. 2 , with some components removed as compared to the trailer of FIG. 5 .
[0010] FIG. 7 is a top plan view of the trailer of FIG. 2 .
[0011] FIG. 8 is a partial, perspective view of the trailer of FIG. 2 , providing HVAC to a tent.
[0012] FIG. 9 is a rear elevational view of a HVAC unit.
[0013] FIG. 10 is a rear elevational view of the FIG. 9 HVAC unit with access doors removed.
[0014] FIG. 11 is a right side elevational view of the FIG. 10 HVAC unit.
[0015] FIG. 12 is a front elevational view of the FIG. 10 HVAC unit.
[0016] FIG. 13 is a left side elevational view of the FIG. 10 HVAC unit.
[0017] FIG. 14 is a schematic illustration of one configuration of an automatic control touch screen.
[0018] FIG. 15 is a schematic illustration of a manual control touch screen.
DETAILED DESCRIPTION
[0019] For the purpose of promoting an understanding of the disclosure, reference will now be made to certain embodiments thereof and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of this disclosure is thereby intended, such alterations, further modifications and further applications of the principles described herein being contemplated as would normally occur to one skilled in the art to which the disclosure relates. In several figures, where there are the same or similar elements, those elements are designated with similar reference numerals.
[0020] Referring now to FIG. 1 , a diagram of an integrated portable unit for providing electricity, air-conditioning and heating is illustrated as system 150 . System 150 generally comprises engine 20 , generator 30 , compressors 40 and 50 , controller 60 , HVAC duct 100 , AC exhaust duct 120 and engine compartment 130 all positioned in vehicle 10 .
[0021] HVAC duct 100 includes bypass 101 , inlets 102 , filter 104 , radiator 24 , evaporator coil 46 , blower 106 , heaters 110 and 112 , thermocouple 114 , and outlet 108 . Bypass 101 circulates air from the vicinity of outlet 108 back to the vicinity of inlets 102 . In the illustrated embodiment, approximately 20% of the airflow is redirected from the vicinity of outlet 108 back to the vicinity of inlets 102 by bypass 101 . In another embodiment, bypass 101 redirects approximately 10% of the airflow from the vicinity of outlet 108 back to the vicinity of inlets 102 . In yet another embodiment, bypass 101 redirects between approximately 0-20% of the airflow from the vicinity of outlet 108 back to the vicinity of inlets 102 . Thermocouple 114 provides temperature feedback of the operation of heaters 110 and 112 and may be used as an over-temperature sensor.
[0022] Radiator 24 is coupled to engine 20 via heat transfer fluid line 22 that transfers a heat transfer fluid such as oil, water or glycol between engine 20 and radiator 24 . In the illustrated embodiment, the heat transfer fluid is oil that also serves to lubricate engine 20 .
[0023] System 150 also includes wireless temperature and humidity sensor 116 remotely located in the space being heated and/or cooled and/or dehumidified which is also where outlet 108 and inlets 102 are placed during operation. In one embodiment, wireless temperature and humidity sensor 116 is a DX80N9X1S1H WIRELESS SERIAL FLEXPOWER SNSR mounting a M12FTH2Q SERIAL TEMP/RH SMART SENSOR. The system also includes a DX80G9M6S4P4M2M2 WIRELESS GATEWAY that operates as a receiver in vehicle 10 (not illustrated) and a DX85M6P6 MODBUS RTU SLAVE EXP I/O module connected between the wireless gateway and controller 60 . These components are offered by BANNER ENGINEERING at http://www.bannerengineering.com/en-US/.
[0024] Engine 20 is coupled to fuel tank 28 and engine 20 includes radiator 26 , intake 27 and exhaust conduit 29 . In the illustrated embodiment, fuel tank 28 has a 90-gallon capacity and engine 20 includes an integrated fan (not illustrated) to force airflow across radiator 26 . Radiator 26 and intake 27 are located in engine compartment 130 . Exhaust conduit 29 is ported outside of vehicle 10 . Engine 20 has a mechanical output 21 coupled to mechanical input 31 of generator 30 . The coupling between mechanical output 21 and input 31 can be of any form known in the art. The illustrated embodiment uses a direct coupling. Generator 30 includes receptacles 32 and power output 34 . Power output 34 powers compressors 40 and 50 , blowers 106 and 122 and heaters 110 and 112 , among other components.
[0025] Receptacles 32 can be located anywhere desired in, on or outside vehicle 10 . In one embodiment, receptacles 32 include two duplex boxes mounted on the exterior of vehicle 10 and two runs of 2 / 0 cable that each have six outlets that can be deployed remotely from vehicle 10 . The two runs of cable can be coupled to generator 30 via removable industrial connections. Circuit breakers (not illustrated) and voltage transformers (not illustrated) can be located between receptacles 32 and generator 30 .
[0026] Compressors 40 and 50 are part of refrigeration cycle system 140 that includes condenser coils 42 and 52 , expansion valve 44 , evaporator coil 46 , hot gas bypass (HGBP) 48 and HGBP valve 49 . Condenser coils 42 and 52 are located in AC exhaust duct 120 . AC exhaust duct 120 includes inlet 124 , outlet 126 and blower 122 . HGBP 48 delivers hot refrigerant vapor between expansion valve 44 and evaporator coil 46 when HGBP valve 49 is opened. One use of HGBP 48 is to increase the humidity removal capacity of evaporator coil 46 without excessively cooling the airflow in HVAC duct 100 . In some embodiments, HGBP valve 49 can approximately infinitely vary the rate of hot gas flow. In other embodiments, HGBP valve 49 acts as an on/off valve.
[0027] In the embodiment illustrated in the FIGs., engine 20 is an oil cooled, 208 Volt, 3-phase DEUTZ 2011 diesel engine that includes oil access ports. The DEUTZ 2011 engine includes an internal oil pump system (not illustrated) that supplies sufficient pressure to circulate oil through radiator 24 and heat transfer fluid line 22 . The DEUTZ 2011 engine also includes temperature springs and diaphragms that control the flow of oil out of the ports. In the illustrated embodiment, the springs and diaphragms are removed and replaced by control valve 23 operated by controller 60 . However, in other embodiments the temperature springs and diaphragms could also be used to regulate oil flow to radiator 24 in addition to the use of control valve 23 .
[0028] Other embodiments (that are not illustrated) can us other types of engines including a YANMAR 4TNV98T diesel engine. In an embodiment utilizing an YANMAR diesel engine, glycol is used as a heat transfer fluid in line 22 and radiator 24 .
[0029] Controller 60 operates to control the function of engine 20 , generator 30 , compressors 40 and 50 , control valve 23 , blowers 106 and 122 , heaters 110 and 112 , and HGBP valve 49 . Interface 62 provides a human interface to operate controller 60 . In the illustrated embodiment, interface 62 comprises a touch-screen, buttons and switches. Particulars of controller 60 are described below.
[0030] In heating mode, system 150 operates to provide heating through a combination of radiator 24 and heaters 110 and 112 . Controller 60 operates control valve 23 to permit the flow of the heat transfer fluid through radiator 24 and regulates power to heaters 110 and 112 based on feedback received from wireless temperature and humidity sensor 116 that is remotely located in the space being heated. In cooling and/or humidity control mode, controller 60 operates compressors 40 and 50 and HGBP valve 49 to regulate the temperature and humidity of the air passing through HVAC duct 100 based upon temperature and humidity readings from wireless temperature and humidity sensor 116 remotely located in the space being conditioned.
[0031] In the illustrated embodiment, engine 20 and generator 30 are configured as a 45 kW generator set. Refrigeration cycle system 140 is a 120,000 BTU system and heaters 110 and 112 are each 15 kW heaters. System 150 has a maximum heat output of approximately 40 kW utilizing radiator 24 and heaters 110 and 112 . At 40 kW of heat output, the illustrated system 150 consumes approximately 3.5 gallons of diesel fuel each hour.
[0032] Referring now to FIG. 2 through FIG. 8 , an embodiment of system 150 is illustrated and mounted on a trailer 10 (which serves as vehicle 10 ). Trailer 10 includes hitch 12 , wheels 14 , engine access panel 16 and 17 and rear door 18 . Trailer 10 also includes outlet 126 and exhaust 134 , muffler 136 , inlet 124 and 132 , light station 70 , warning light 64 , siren 66 , controller 60 and control panel interface 62 . Light station 70 is configured to be folded and stowed on the top of trailer 10 as shown in FIG. 7 . Light station 70 can be elevated to the illustrated position of FIG. 2 and rotated and pitched to provide illumination in a desired direction. Muffler 136 is connected to exhaust conduit 29 . Warning light 64 and siren 66 are operated by controller 60 to provide audio and visual warnings of important events such as low fuel. Trailer 10 holds many of the components of system 150 ; including engine 20 , generator 30 , and refrigeration cycle system 140 , contained on HVAC unit 90 (as illustrated in FIG. 5 and described below with respect to FIGS. 9-13 ). In terms of the direction and orientation of vehicle 10 , now trailer 10 , the towing end is the front and the opposite end is the rear. The left and right sides are determined based on facing the trailer 10 from the towing end.
[0033] Referring to FIG. 8 , trailer 10 is illustrated in use to supply heated or cooled air to space 1 , which, as shown in FIG. 8 , is a portable tent. Return hose 103 and supply hose 109 are flexible 18 inch ducts connecting inlets 102 and outlet 108 to space 1 . In other embodiments, space 1 could be a building, trailer or any other at least partially enclosed space in which HVAC is desired.
[0034] Referring now to FIG. 9 through FIG. 13 , HVAC unit 90 is illustrated. HVAC unit 90 is a self-contained palletized unit that includes refrigeration cycle system 140 , HVAC duct 100 and AC exhaust duct 120 (also see FIG. 1 ).
[0035] HVAC unit 90 includes inlets 102 , outlet 108 , compressors 40 and 50 , condenser coils 42 and 52 , head pressure transducer 45 , evaporator coil 46 , drain 47 , blowers 106 and 122 , HGBP valve 49 , HGBP solenoid 49 a, expansion valve 44 , filter rack 105 , holding filters 104 , and heaters 110 and 112 . Drain 47 is located under evaporator coil 46 to collect and drain any condensed water.
[0036] HVAC unit 90 is configured with HVAC duct 100 on the bottom portion and AC exhaust duct 120 on the top portion, HVAC duct 100 and AC exhaust duct 120 are separated from each other by bulkhead 94 . HVAC unit 90 also comprises frame units 92 that define the periphery of the palletized unit. HVAC duct 100 and AC exhaust duct 120 are both defined by approximately “U” shaped air flow passages through HVAC unit 90 . For example, flow divider 95 , as shown in FIGS. 10 , 11 and 13 , defines and separates inlets 102 from outlets 108 (as shown in FIG. 9 ). As shown in FIGS. 11 and 13 , bypass 101 can be defined by adjustable vents located in flow divider 95 .
[0037] AC exhaust duct 120 is located above HVAC duct 100 so that compressors 40 and 50 and HGBP 48 are located above expansion valve 44 . HVAC unit 90 is configured such that it can be inserted and removed from trailer 10 as a single unit, however, it should be understood that in other embodiments, HVAC unit 90 could be directly incorporated into trailer 10 or any other type of vehicle 10 .
[0038] Referring now to FIGS. 14 and 15 , one embodiment of interface 62 is illustrated as touch screens 200 and 300 . FIG. 14 illustrates automatic control touch screen 200 while FIG. 15 illustrates a manual control touch screen 300 . In this embodiment, controller 60 and interface 62 are an integrated PLC with a HMI user interface screen that provides a “one-touch” user interface with the entire system. The touch screens allow the user to select the desired result without any training in the operation of the individual components that make up system 150 . Integrated controller 60 operates the system to provide the desired result selected by the user via interface 62 . For example, when system 150 is set up with return hose 103 , supply hose 109 and wireless temperature and humidity sensor 116 positioned in an enclosed space such as a tent, selection of the desired air conditioning or heating option on the touch screens described below operate system 150 to heat or cool the air in the tent to the desired conditions regardless of environmental conditions (within the operating capacity of system 150 ).
[0039] Automatic control touch screen 200 includes the following ON/OFF touch screen control inputs: auto cool 210 , auto heat 220 , AC power only 230 , each of which provide ON/OFF toggling with visible feedback of the selected mode. Automatic control touch screen 200 also includes temperature readout 240 , humidity readout 250 , temperature set point 260 , amperage readout 270 , fuel gauge readout 280 , manual mode select 290 and alarm silence 292 . Temperature readout 240 and humidity readout 250 display measurements from wireless temperature and humidity sensor 116 . Amperage readout 270 indicates the current amperage load on generator 30 . Fuel gauge 280 indicates the fuel level in fuel tank 28 determined from a fuel level sensor (not illustrated). The actual numbers shown on readouts 240 , 250 , 260 and 270 are for example only. The same is true for the fuel level, the actual reading is for example only. Temperature set point 260 displays the current programmed set point. Selecting temperature set point 260 on touch screen 200 brings up a keypad on the touch screen that the user can use to input a desired temperature set point. Temperature set point 260 is utilized with both the auto cool and auto heat control schemes. Selecting auto cool 210 activates the auto cool control scheme and deactivates both the auto heat and AC power only control schemes. Selecting auto heat 220 activates the auto heat control schemes and deactivates both the auto cool and AC power only control schemes. Selecting AC power only 230 activates the AC power only control scheme and deactivates both the auto cool and auto heat control schemes. Selecting manual mode select 290 changes the active touch screen to manual control touch screen 300 as described below.
[0040] When the auto cool control scheme is activated, controller 60 automatically deactivates the auto heat and AC power only control schemes. Controller 60 then compares the measured temperature with temperature set point. If the measured temperature is more than 3° F. hotter than the temperature set point then compressor 40 and possibly compressor 50 are activated by controller 60 . Controller 60 also compares the humidity measured by wireless temperature and humidity sensor 116 with a programmed set point of 40% humidity plus or minus 10%. When the humidity measured exceeds 50%, controller 60 activates solenoid 49 a to open hot gas bypass valve 49 and when the measured humidity is less than 30% then solenoid 49 a is deactivated to close hot gas bypass valve 49 . Selection of auto cool 210 also activates blowers 106 and 122 . The choice of using either condenser 40 or condensers 40 and 50 is made by a standard refrigeration control algorithm known to those skilled in the art. Under the auto control scheme, engine 20 is cooled by radiator 26 .
[0041] In other embodiments where HGBP valve 49 is approximately infinitely variable, controller 60 can vary the setting of HGBP valve 49 to control the humidity within narrower control parameters as is known in the art. While the illustrated embodiment does not permit operator modification of the humidity set point, this option could be added to interface 62 by adding a control input set point for humidity, similar to temperature set point 260 .
[0042] Engaging the auto heat control scheme initially engages blower 106 and powers heater 110 . After running for approximately four minutes, controller 60 then opens control valve 23 to permit the flow of engine heat transfer fluid through radiator 24 . Controller 60 then operates heaters 110 and 112 by comparing the temperature measured by sensor 116 with the programmed set point to be controlled within plus or minus 3° F. After the four-minute delay, control valve 23 remains open as long as the auto heat control scheme is selected.
[0043] Engaging the AC power only control scheme starts engine 20 and controls power output from engine 20 to match the demand from generator 30 . In this mode, blowers 106 and 122 are disengaged. Control valve 23 and HGBP valve 49 are closed and compressors 40 and 50 are off as well as heaters 110 and 112 . In this mode, engine 20 is cooled by radiator 26 .
[0044] Referring to FIG. 15 and manual control touch screen 300 , this screen includes the following ON/OFF touch screen control inputs: manual cool selection 310 , manual high fan 320 , manual hot gas 330 , AC power only 340 , manual heat 350 , manual low fan 360 , and manual hot oil 370 . Also included is auto control screen selection 380 . Selectors 310 , 320 , 330 , 340 , 350 , 360 and 370 each have ON/OFF toggle displays providing feedback of the current operating mode. Selection of manual cool 310 disengages manual heat 350 and AC power only 340 and manual hot oil 370 and activates compressors 40 and 50 . Selection of manual cool 310 also requires a selection of either manual high fan 320 or manual low fan 360 which are mutually exclusive wherein selection of one automatically deselects the other. When manual cool 310 is selected, manual hot gas 330 may optionally be activated which opens HGBP valve 49 .
[0045] Selection of AC power only 340 engages engine 20 and disengages compressors 40 and 50 and heaters 110 and 112 . Selection of manual heat 350 activates heaters 110 and 112 and also requires selection of either manual high fan 320 or manual low fan 360 . Selection of manual heat 350 also deactivates any previous activation of manual cool 310 or AC power only 340 . Selection of manual hot oil 370 opens control valve 23 . In some embodiments an approximate four minute delay is incorporated between the selection of manual hot oil 370 and the opening of control valve 23 . In other embodiments, there is no delay between the selection of manual hot oil 370 and the opening of control valve 23 .
[0046] As used herein, “above” and “top” the refer to conventional use of such terms as illustrated in the drawings with the top of each page being “above” the bottom, with trailer 10 positioned with wheels 14 on a level ground surface and hitch 12 connected to a motorized vehicle at the approximate relative height illustrated in the drawings. Describing a first component as being positioned above a second component indicates that the first component is further from the ground surface than the second component but does not necessary require that the second component is between the first component and the ground surface.
[0047] While the disclosure has been illustrated and described in detail in the drawings and foregoing description, the same is to be considered as illustrative and not restrictive in character, it being understood that only the preferred embodiments have been shown and described and that all changes and modifications that come within the spirit of the disclosure are desired to be protected. | Disclosed is an integrated unit packaged on a vehicle for providing electricity, air-conditioning and heating to a space remote from the vehicle. The unit includes an electric generator system, a ventilation system, a refrigeration cycle system, each of which is powered by the electric generator system, a heater that is also powered by the electric generator system and electrical outlets that are also powered by the electric generator. | 1 |
FIELD OF THE INVENTION
[0001] The invention relates to a clamping device for a printing plate on a cylinder according to the preamble of claim 1 .
[0002] The subject of the invention is a cylinder having a clamping device for fastening a plate, in particular a printing plate, to the periphery of the cylinder, the clamping device comprising a first clamping element, a pivotably mounted second clamping element, a spring part and a tensioning element, which can be moved between a clamping position, in which it holds the printing plate clamped in between the clamping elements, and a released position, in which the clamping elements release the printing plate. With the cylinder for example incorporated in a rotary press, printing plates with different thicknesses, such as those which occur in what is known as the letterpress process, for example, can be fastened to the periphery of the cylinder.
PRIOR ART
[0003] A clamping device for fastening a printing plate to a press cylinder is disclosed, for example, by DE 690 20 463 T2. The clamping device comprises a clamp W for an upper edge of the printing plate and a clamp S for a lower edge of the printing plate. The two clamps W and S each comprise two clamping bars, between which the corresponding edge of the printing plate is clamped.
[0004] The necessary clamping force is respectively ensured by a tensioning spindle, which is rotatably mounted between the clamping bars. The tensioning spindle has a cross section which is substantially circular, apart from a flat. It can be rotated into a position in which it presses with a maximum diameter against the two clamping bars and, in the process, clamps the printing plate between them, or else rotated into a position in which, because of a width shortened by the flat, it can no longer exert any clamping force on the clamping bars and the printing plate is released. However, with the embodiment shown, it is not possible to set the clamping force optimally to a specific thickness of the printing plate in order to fasten printing plates of different thicknesses. For example, printing plates with a low thickness are not clamped in firmly enough or even not at all in a gap between the clamping bars, while printing plates with a greater thickness under certain circumstances cannot even be inserted into the gap between the clamping bars.
[0005] In EP 04 35 410 B2, a clamping device that is configured differently is shown. In the case of this clamping device, too, an edge of the printing plate is clamped in between two clamping bars. One of the clamping bars is pivotably mounted and is pressed against the other clamping bar by a resilient spring. In order to open the two clamping bars, a spindle with an eccentric cross section is provided, with which the pressure of the resilient spring can be counteracted. Although, in the case of this device, in the event of different thicknesses of the printing plate, the resilient spring is pressed in to different extents, which leads to a correspondingly changed spring force and therefore to a changed clamping force for the printing plate, this clamping force is firstly weak, because the resilient spring can exert only small spring forces, as a result of which printing plates with an excessively high thickness cannot be held in this clamping device. Secondly, during the insertion of the printing plate between the clamping bars, care must be taken that the spindle acts permanently counter to the spring force. This requires a fixing mechanism for the spindle, which means increased mechanical complexity, since without such a fixing mechanism there is the risk that, during the insertion of the printing plate, the spindle will slip and release the pivotable clamping bar again, which will then be pressed immediately against the other clamping bar because of the spring force. However, even with such a fixing device for the spindle, the insertion of the printing plate is cumbersome and associated with a risk of injury, since, in particular when the printing plate has a great thickness, it has a certain stiffness, which has to be overcome when bending over the printing plate and introducing it between the two clamping bars.
[0006] As a consequence of this stiffness, the printing plate continually attempts to bend back again, so that it has to be held between the clamping bars while the fixing device for the spindle is released, in order that the clamping bars are are able to grip the printing plate. In this case, there is the risk to a person holding the printing plate that his fingers will be clamped in between the clamping bars. If the printing plate is mounted by only one person, the risk of injury is increased considerably, since he has to hold the printing plate with one hand while he simultaneously has to operate the fixing device for the spindle with the other hand.
[0007] DE 26 06 773 B2 discloses a device for fastening a printing plate on a cylinder, in which the printing plates are held between fixed clamping bars and movable clamping elements. The clamping elements are moved by a pivotable, flattened spindle by means of interposed disk springs.
SUMMARY OF THE INVENTION
[0008] The invention is based on the object of providing a clamping device for a printing plate.
[0009] According to the invention, the object is achieved by the features of claim 1 .
[0010] The advantages that can be achieved with the invention are in particular that printing plates with different thicknesses can be fastened to the cylinder. By means of the special design of the clamping device, it is ensured that each printing plate experiences a clamping force from the clamping device which corresponds to its thickness, and is gripped securely by the clamping elements. Furthermore, the play of the tensioning element between the clamping elements in the released position prevents the clamping elements inadvertently snapping shut and, as a result, reduces the risk of injury. In addition, the mounting of the printing plate is simplified considerably, since it can firstly be introduced carefully between the clamping elements and is held by the latter before it is acted on with a clamping force by moving the tensioning element into the clamping position.
[0011] The spring part preferably comprises at least one disk spring. As opposed to tensioning springs, disk springs have a considerably greater spring constant with a compact design and are therefore capable of exerting a much higher spring force with less compression. This permits a more compact and space-saving design of the clamping device, which is additionally capable of holding printing plates with a thickness in which a clamping device designed with resilient springs could not supply the clamping force needed for this purpose.
[0012] The clamping device is preferably arranged in an elongated groove in the cylinder. Because the clamping device is countersunk completely in the groove, the cylinder can be used, for example, as a plate cylinder in a rotary press without the clamping device impeding the printing operation.
[0013] In this case, a clamping device which can be displaced within the groove is particularly preferred. Using such a clamping device, the printing plate held by the clamping device can be tensioned by displacing the clamping device in the peripheral direction within the groove, so that the printing plate rests closely on the periphery of the cylinder, or can be displaced as a whole in the peripheral direction. The clamping device can also be displaceable along the groove. In a machine which has a plurality of plate cylinders for multicolor printing, the individual printing plates can be adjusted in register with the aid of such clamping devices.
[0014] In this case, at least one of the clamping elements is preferably a bar running parallel to the groove. By using such bars, a printing plate can be clamped in along an entire length of one of its end sections, which improves the clamping.
[0015] One side of the first clamping element, with which the first clamping element clamps the printing plate, preferably has a curved profile in section transversely with respect to the axis of the cylinder. In this case, depending on the suitability, the curved profile can be curved in the shape of a circular arc or a section of an ellipse or in any other desired way. Such a configuration of the first clamping element benefits kink-free clamping of the printing plate.
[0016] Likewise preferred is a tensioning element which is a spindle running parallel to the groove. In the case of bar-like clamping elements, by means of a tensioning element embodied in this way, a clamping force may be applied along an entire length of the clamping elements, which benefits the secure clamping of the printing plate.
[0017] The spindle preferably has a cross section substantially in the form of a circular segment with a first flat. Such a spindle may be moved from the clamping position into the released position and vice versa by means of simple rotation. Here, in the released position, the flat is oriented substantially toward one of the two clamping bars, which results in the play of the spindle in the interspace between the clamping bars.
[0018] A further embodiment of the spindle has a second flat and a third flat, which are arranged diametrically with respect to each other on the spindle, in the clamping position the second flat pressing against the second clamping element and the third flat being pressed by the spring part. The second and the third flat have the effect that the spindle latches in in the clamping position.
[0019] There are advantageously pins in one of the clamping elements, on which pins the printing plate is hooked in. By virtue of the pins, the mounting of the printing plate is simplified further, since it is prevented from sliding out between the two clamping elements.
[0020] As already mentioned, the cylinder is particularly preferably a part of a rotary press.
[0021] An exemplary embodiment of the invention is illustrated in the drawings and will be described in more detail in the following text.
BREIF DESCRIPTION OF THE DRAWINGS
[0022] In the drawings:
[0023] FIG. 1 shows a cross section through a part of a cylinder and a clamping device;
[0024] FIG. 2 shows a front view of a first clamping element.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0025] FIG. 1 shows a cross section through a part of a cylinder 01 with an associated clamping device 02 . In this case, the clamping device 02 is arranged within a longitudinal groove 11 in the cylinder 01 and entirely accommodated in this groove 11 . Fastened to the periphery of the cylinder 01 is a plate 03 , for example a printing plate 03 , which is bent down in one end section and is clamped in the clamping device 02 .
[0026] The clamping device 02 includes a first clamping element 04 , a second clamping element 06 , a bearing block 17 having a spring part 07 and a tensioning element 08 . The first clamping element 04 is an L-profile bar 04 extending through the length of the groove 11 . Arranged in a limb 18 of the L-profile bar 04 which is vertical in the drawing are pins 16 , which project with one end section out of the end of the limb 18 and reach with a form fit through holes in the edge of the printing plate 03 . In a limb 19 of the L-profile bar 04 which is horizontal in FIG. 1 , on the side of the limb 18 , a recess 21 is provided in an end section of the limb 19 opposite the limb 18 . The L-profile bar 04 is arranged within the groove 11 in such a way that the limb 18 is oriented toward an aperture 22 of the groove 11 in the surface of the cylinder 01 , and the limb 19 points away from the aperture 22 .
[0027] The bearing block 17 rests on the horizontal limb 19 of the L-profile bar 04 and on the vertical limb 18 . At an end section facing the vertical limb 18 , the bearing block 17 has a rotary bearing 23 . In an end section facing away from the vertical limb 18 , the bearing block 17 has a channel-like groove 24 running parallel to the groove 11 . The second clamping element 06 is attached to the rotary bearing 23 , while the groove 24 serves as a bearing 24 for the tensioning element 08 . At the lowest point of the bearing 24 an aperture 26 is provided as an engagement for the spring part 07 .
[0028] The second clamping element 06 extends through the length of the groove 11 and is attached to the rotary bearing 23 such that it can pivot about a longitudinal axis. Thus, the clamping element 06 acts like a two-armed lever. A lever arm facing the aperture 22 forms a clamping bar 06 , which rests on the vertical limb 18 of the L-profile bar 04 . The clamping bar 06 has holes 27 , into which the pins 16 projecting from the limb 18 project.
[0029] The tensioning element 08 is a spindle 08 which extends through the length of the groove 11 . The spindle 08 substantially has a cross section in the form of a circular segment with a wide first flat 12 . Provided on the spindle 08 , diametrically with respect to each other, are two further flats 13 and 14 , which are parallel to each other and are both arranged at right angles to the flat 12 . The flats 13 and 14 are much narrower than the flat 12 . The spindle 08 extends over the entire length of the bearing block 17 and is rotatably mounted in its groove 24 . The spacing of the flats 13 , 14 from the axis of rotation of the spindle 08 corresponds to the radius of curvature of the part of the cross section that is in the form of a circular segment; the spacing of the flat 12 from the axis of rotation is smaller.
[0030] The spring part 07 comprises a plurality of springs 09 , for example disk springs 09 , on which a plate 28 is mounted. The plate 28 has a protrusion 29 on a side facing away from the disk springs 09 . The disk springs 09 and the plate 28 are accommodated by the recess 21 in the horizontal limb 19 of the L-profile bar 04 . In this case, the protrusion 29 reaches through the aperture 26 in the bearing block 17 into the interior of the bearing 24 and presses against the spindle 08 located in the latter.
[0031] When the spindle 08 is in a released position, it is oriented with the first flat 12 either toward a lever arm of the clamping bar 06 facing away from the aperture 22 or toward the protrusion 29 of the spring part 07 . It then has play within the bearing 24 , that is to say in an interspace between the spring part 07 or the protrusion 29 of the spring part 07 and the clamping bar 06 . The disk springs 09 press the plate 28 against the bearing block 17 . The clamping bar 06 can pivot freely about the rotary bearing 23 and can be pivoted back in order to release the pins 16 .
[0032] In order to fasten the printing plate 03 , first of all an edge section of the printing plate 03 provided with holes is pushed through the aperture 22 in the groove 11 in the periphery of the cylinder 01 and hooked onto the pins 16 by means of the holes. The printing plate 03 is then bent around the cylinder 01 and an opposite edge section is hooked in a second groove 11 in the same way. In order to avoid the bending leading to permanent deformation of the printing plate 03 , the limb 18 of the L-profile bar 04 has a curved profile in section transversely with respect to an axis of the cylinder 01 , as shown in FIG. 2 . In the embodiment of the L-profile bar 04 shown, the curvature has the form of a circular section.
[0033] In order to clamp the printing plate 03 between the two clamping elements 04 and 06 , the spindle 08 is rotated into the clamping position shown in FIG. 1 . In this position, it presses with its second flat 13 against the clamping bar 06 and with the third flat 14 against the protrusion 29 of the spring part 07 . In order to assume this position, an additional expenditure of force, which can easily be applied, is necessary so that the spindle 08 is latched in the clamping position by virtue of the flats 13 and 14 . The disk springs 09 are compressed by the spindle 08 via the protrusion 29 . They react to this with a spring force which, via the protrusion 29 , acts on the spindle 08 and on the second clamping element 06 . Since the second clamping element 06 acts like a two-armed lever as a result of its pivotable mounting on the rotary bearing 23 , the printing plate 03 is clamped in between the clamping bar 06 of the second clamping element 06 and the limb 18 of the L-profile bar 04 .
[0034] Depending on the thickness of the printing plate 03 clamped in, the disk springs 09 are compressed either more or less and react with a correspondingly different spring force, that is to say the clamping force for the printing plate 03 increases with the thickness of the printing plate 03 , since the disk springs 08 are compressed to a greater extent with increasing thickness of the printing plate 03 . Thus, in this embodiment of the clamping device 02 , a clamping force corresponding to the thickness of the printing plate 03 is automatically established by itself.
[0035] After the printing plate 03 has been clamped in between the L-profile bar 04 and the clamping element 06 , the clamping device 02 is pushed away from the aperture 22 within the groove 11 , in order to tension the printing plate 03 on the periphery of the cylinder 01 . For this purpose, a tensioning screw 31 is provided, which strikes a wall of the groove 11 and with which the clamping device 02 can be displaced toward the aperture 22 or away from the aperture 22 within the groove 11 .
[0036] After printing has been carried out, the printing plate 03 is removed from the cylinder 01 by the spindle 08 being rotated into the released position again, in which said plate has play in the interspace between the spring part 07 and the second clamping element 06 , so that the second clamping element 06 can again be pivoted freely. Now, the clamping bar 06 of the second clamping element 06 can easily be pivoted back, as a result of which the pins 16 are exposed and the printing plate 03 can be unhooked from the pins 16 .
[0037] The invention is not restricted to the embodiment described. Instead, alternative configurations of the clamping device 02 shown are possible without departing from the idea of the invention. For example, in the described configuration of the clamping device 02 , the first clamping element 04 or the L-profile bar 04 is a bar that extends over the entire length of the groove 11 , the second clamping element 06 also being configured as a continuous bar. As an alternative to this, the second clamping element 06 can be composed of a plurality of clamping levers which are attached to a plurality of bearing blocks 17 . Likewise, the first clamping element 04 can be composed of a plurality of L-profile pieces 04 , on which the bearing blocks 17 rest, instead of being formed as a continuous L-profile bar 04 . Quite generally, the first clamping element 04 and the second clamping element 06 can be formed in any desired combination in one piece as bars or can be composed of a plurality of pieces.
LIST OF DESIGNATIONS
[0000]
01 Cylinder
02 Clamping device
03 Plate, printing plate
04 First clamping element, L-profile bar
05 -
06 Second clamping element, clamping bar
07 Spring part
08 Tensioning element, spindle
09 Spring, disk springs
10 -
11 Groove
12 First flat
13 Second flat
14 Third flat
15 -
16 Pin
17 Bearing block
18 Vertical limb
19 Horizontal limb
20 -
21 Recess
22 Aperture
23 Rotary bearing
24 Groove, bearing
25 -
26 Aperture
27 Holes
28 Plate
29 Protrusion
30 -
31 Tensioning screw | Disclosed is a clamping device ( 02 ) for fastening a plate ( 03 ) to the periphery of a cylinder ( 01 ). Said clamping device ( 02 ) comprises a first clamping element ( 04 ), a pivotally mounted second clamping element ( 06 ), a spring part ( 07 ), and a bracing element that is embodied as a pivotable spindle ( 08 ) and is movable between a clamping position in which the bracing element maintains the plate in a clamped state between the clamping elements and a released position in which the clamping elements release the plate. The spindle ( 08 ) is mounted in a groove so as to be displaceable, is fixed in an intermediate space between the spring part ( 07 ) and the second clamping element ( 06 ), and is pressed against the second clamping element by means of the spring part in the clamping position. | 1 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a national phase application of international application no. PCT/NO2008/000283, filed on Aug. 6, 2008, which claims the benefit of and priority to Norwegian application no. 20074140, filed on Aug. 9, 2007. The disclosures of the above-referenced applications are incorporated herein by reference in their entireties.
FIELD OF THE INVENTION
[0002] This invention relates to an actuator. More particularly, it relates to an actuator for moving a tool within a borehole in the ground, the actuator being positioned between a coiled tubing and a tool, and the actuator being arranged to move the tool at a substantially constant axial speed. The actuator includes an actuator housing with an internal cylinder jacket and an end wall, there being arranged at the end wall a releasable nut which engages, in its active position, a threaded, axially bored-through mandrel, the mandrel projecting, axially movable, through an opening in the end wall. A motor is arranged to rotate the mandrel about its longitudinal axis via a non-circular, axially bored-through shaft. A locking piston, which is movable within the cylinder jacket, surrounds the mandrel, the locking piston being arranged to lock, when it is in its end position nearest to the end wall, the nut in its active position. An inner through opening in the wall of the shaft communicates with a first space in the actuator housing upstream relative to the locking piston when the mandrel is in its retracted position within the actuator housing, whereas an outer through opening in the wall of the mandrel communicates with a second space between the locking piston and the end wall when the mandrel is in its extended end position.
BACKGROUND
[0003] During work in a borehole, for example, the cleaning of a pipe, which is in the borehole, by means of a pressure-fluid tool which is on the end portion of a coiled tubing, it is well known that the feeding rate of the tool into the borehole may be irregular even though the coiled tubing is fed into the borehole at a regular rate.
[0004] The reason for this irregular rate of conveyance may be friction between the coiled tubing and borehole wall, obstructions in the borehole or curved boreholes, in which the coiled tubing changes the radius of curvature as it is being fed in. These conditions may result in a so-called “stick slip” effect, in which the tool stops, only to be moved, next, at a relatively high speed.
SUMMARY OF THE INVENTION
[0005] The invention has for its object to remedy or reduce at least one of the drawbacks of the prior art.
[0006] The object is achieved in accordance with the invention through the features which are specified in the description below and in the claims that follow.
[0007] An actuator in accordance with the invention for moving a tool within a borehole in the ground, the actuator being positioned between a coiled tubing and a tool, and the actuator being arranged to move the tool at a substantially constant axial speed, is characterized by the actuator including an actuator housing with an internal cylinder jacket and an end wall, a releasable nut being arranged at the end wall, engaging, in its active position, a threaded, axially bored-through mandrel, the mandrel projecting, axially movable, through an opening in the end wall, and a motor being arranged to rotate the mandrel about its longitudinal axis via a non-circular, axially bored-through shaft, and a locking piston, movable in the cylinder jacket, surrounding the mandrel, the locking piston being arranged to lock, when it is in its end position nearest to the end wall, the nut in its active position, and an inner through opening in the wall of the shaft communicating with a first space in the actuator housing upstream relative to the locking piston when the mandrel is in its retracted position within the actuator housing, and an outer through opening in the wall of the mandrel communicating with a second space between the locking piston and the end wall when the mandrel is in its extended end position.
[0008] In its initial position the mandrel is in its retracted position, the locking piston is in an intermediate position between the piston and the nut, whereas the motor rotates the mandrel and thereby the tool about the longitudinal axis of the mandrel. Pressurized fluid flows through the axial bores of the shaft and mandrel.
[0009] Pressurized fluid flows via the inner opening into the first space, moving the locking piston up to the nut, where the locking piston causes the nut to be moved from its inactive position into its active position, engaging the threads of the mandrel.
[0010] The motor thereby feeds the mandrel out of its retracted position, whereby the liquid flow via the inner opening is shut off.
[0011] As the mandrel takes its projecting end position, the outer opening is uncovered, whereby pressurized fluid may flow into the second space. The locking piston is moved away from the nut which is thereby moved back into its inactive position.
[0012] With advantage, the mandrel is provided with a piston which is sealingly movable within the cylinder jacket. The fluid pressure moves the locking piston and the piston together with the mandrel in the direction of their initial positions. The further movement of the mandrel into its initial position may take place by means of, for example, a force directed at the actuator from the tool.
[0013] In an alternative embodiment the mandrel may be connected to a spring or gas spring which is arranged to move the mandrel in an inward direction within the actuator housing.
[0014] In a further embodiment the mandrel is moved inwards within the actuator housing by means of an external displacing force.
[0015] With advantage, the locking piston is provided with releasable locking dogs fitting complementarily into a locking groove in the cylinder jacket, the piston being provided with a releaser which is arranged to release the locking dogs when the piston is near the locking piston.
[0016] The motor is typically driven by means of pressurized fluid, but electric operation may also be applicable under certain conditions. It is advantageous that the motor is in the actuator housing, but the motor may also project, at least partially, from the actuator housing.
[0017] By the motor feeding the mandrel in a direction out of the actuator housing by means of a thread-nut-connection, a steady feeding rate is achieved, even if the axial force on the mandrel should vary somewhat. The device according to the invention provides a relatively simple actuator, in which the mandrel is moved automatically outwards at a constant rate, subsequently returning at a relatively high speed before the feeding out of the mandrel is repeated again.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] In what follows, is described an example of a preferred embodiment which is visualized in the accompanying drawings, in which:
[0019] FIG. 1 shows, partially in section, an actuator in accordance with the invention which is connected between a coiled tubing and a tool coupling;
[0020] FIG. 2 shows, on a somewhat larger scale, the actuator in its initial position;
[0021] FIG. 3 shows the same as FIG. 2 , but here a locking piston is moving within the actuator;
[0022] FIG. 4 shows the actuator after the locking piston has moved the nut of the actuator into its active position;
[0023] FIG. 5 shows the mandrel of the actuator as it is being fed out;
[0024] FIG. 6 shows the actuator as the mandrel is in its projecting position;
[0025] FIG. 7 shows the actuator after the locking piston has been moved from its locking position relative to the nut; and
[0026] FIG. 8 shows a section III-III of FIG. 3 .
DESCRIPTION OF THE INVENTION
[0027] In the drawings the reference numeral 1 indicates an actuator which is fitted between a coiled tubing 2 and a tool, not shown, by means of a tool holder 4 .
[0028] The actuator 1 includes an actuator housing 6 which is provided with an internal cylinder jacket 8 and an end wall 10 at its end portion facing away from the coiled tubing 2 . The end wall 10 is formed with a centric through opening 12 . A pressure-fluid-operated motor 14 with a through centre opening 16 is connected to the actuator housing 6 and the coiled tubing 2 by means of an adapter 18 .
[0029] Just inside the end wall 10 is arranged a nut housing 20 including a number of nut segments 22 pivotal in the nut housing 20 . Each nut segment 22 is pivotal about a nut axle 24 between a passive position, see FIG. 2 , and an active position, see FIG. 4 . The nut segments 22 are held in their passive positions by an annular spring 26 . Together the nut segments 22 constitute a nut 28 .
[0030] In its active position the nut 28 is in engagement with a threaded, axially bored-through mandrel 30 . The mandrel 30 projects, axially movable, through the opening 12 in the end wall 10 , the mandrel 30 being connected to the tool holder 4 .
[0031] At its opposite end portion, extending inwards, the mandrel 30 is provided with a piston 32 which is sealingly movable within the cylinder jacket 8 . A through opening 34 of the mandrel 30 , see FIG. 2 , is along a portion of the opening 34 given a hexagonal shape, see FIG. 8 , complementarily matching an axially bored-through shaft 36 .
[0032] The shaft 36 is rotated about its longitudinal axis by the motor 14 . An inner opening 40 through the wall of the shaft 36 corresponds with a bore 42 in the piston 32 when the mandrel 30 is in its retracted position, see FIG. 2 . The mouth of the bore 42 is on the side of the piston 32 facing the nut 28 .
[0033] A valve sleeve 44 is moved sealingly in over the inner opening 40 by means of a spring 46 as the mandrel 30 is moved away from its retracted position, see FIG. 5 .
[0034] A locking piston 48 which is movable within the cylinder jacket 8 surrounds the mandrel 30 . On its side facing the nut 28 , the locking piston 48 is provided with an externally conical sleeve projection 50 which is arranged to be moved in under the portions 51 of the nut segments 22 facing the locking piston 48 , the locking piston 48 thereby being arranged, when it is in its end position nearest to the end wall 10 , to lock the nut 28 in its active position, in which the nut 28 is in engagement with the mandrel 30 , see FIG. 4 .
[0035] When the mandrel is in its projecting position, an outer opening 52 in the wall of the mandrel 30 is uncovered, the outer opening 52 then having its mouth between the end wall 10 and the locking piston 48 .
[0036] In this preferred embodiment, the locking piston 48 is provided with a number of locking dogs 54 which are arranged to engage a locking groove 56 in the cylinder jacket 8 , see FIG. 4 . The piston 32 is provided with an axially movable, spring-biased release sleeve 58 which is biased in the direction of the end wall 10 by a spring 60 . The release sleeve 58 is arranged to move the locking dogs 54 out of their respective engagements in the locking groove 56 when the piston 32 is at the locking piston 48 , see FIG. 6 .
[0037] In its initial position the mandrel 30 is in its retracted position, the locking piston 48 is in its intermediate position between the piston 32 and the nut 28 . The motor 14 rotates the shaft 36 , the mandrel 30 and thereby the tool, not shown, about the longitudinal axis 62 of the mandrel 30 . Pressurized fluid from the coiled tubing 2 flows via the adapter 18 , centre bore 16 of the motor 14 , shaft 36 and mandrel 30 to the tool holder 4 . At the same time, pressurized fluid is flowing via the inner opening 40 and the bore 42 of the piston 32 into a first space 64 between the piston 32 and the locking piston 48 .
[0038] The locking piston 48 is moved in the direction of the nut 28 by the fluid pressure, see FIG. 3 , until the locking piston 48 hits the nut 28 , the sleeve projection 50 of the locking piston 48 being underneath the projecting portions 51 of the nut segments 22 , whereby the nut segments 22 have been moved into their respective active positions, in which they are in engagement with the mandrel 30 , see FIG. 4 . At the same time, the locking dogs 54 engage the locking groove 56 , thereby preventing the nut 28 from being movable inwards within the actuator housing 6 .
[0039] The rotating mandrel 30 , which is rotated by the motor 14 , is screwed outwards within the actuator housing 16 by means of the nut 28 , see FIG. 5 . The spring 46 in the shaft 36 thereby moves the valve sleeve 44 closingly in over the second opening 40 . Fluid from the first space 64 is evacuated via the bore 42 in the piston 32 . Moreover, the actuator housing 6 can be replenished with fluid from the outside of the actuator 1 via an opening 66 in the actuator housing 6 .
[0040] When the motor 14 has fed the mandrel 30 out into its projecting end position, see FIG. 6 , the release sleeve 58 is underneath the locking dogs 54 , whereby the locking dogs 54 have been pivoted out of their engagement with the locking groove 56 . At the same time, the outer opening 52 communicates with a second space 68 located between the end wall 10 and the locking piston 48 . In this preferred embodiment the nut 28 has been fed out of engagement from the mandrel 30 as well.
[0041] The pressure from the pressurized fluid flowing into the second space 68 works against the locking piston 48 and the force overcomes the force from the spring 60 , whereby the release sleeve 50 is moved sufficiently far back relative to the piston 32 for the sleeve projection 50 of the locking piston 48 to be disengaged from the nut segments 22 , see FIG. 7 . The annular spring 26 moves the nut segments 22 into their respective inactive positions, whereby the mandrel 30 can be moved back into its retracted initial position.
[0042] In the figures are shown a number of seals which have generally been assigned the reference numeral 70 . The purpose and operation of the seals 70 are well known and not described any further. Because of the relatively great flow rate of pressurized fluid prevailing, no great demands are made on the seals 70 . For example, it has turned out to be unnecessary to place a seal between the end wall 10 and the mandrel 30 . | An actuator device for moving a tool within a borehole in the ground, the actuator being positioned between a coiled tubing and a tool, and the actuator being arranged to move the tool at a substantially constant axial speed and the actuator including a motor-operated mandrel which is moved outwards in the actuator by means of a releasable nut, the nut being locked in its active position by means of a hydraulically operated locking piston. | 4 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is a division of U.S. Ser. No. 10/021,456, filed Dec. 13, 2001, which claims the benefit of priority Provisional Application No. 60/255,842, filed Dec. 15, 2000, the disclosures of which are incorporated herein by reference.
TECHNICAL FIELD
[0002] The present invention relates generally to methods of making nonwoven fabrics, and more particularly to a method of manufacturing three-dimensional imaged nonwoven fabrics exhibiting flame-retardant characteristics while retaining aesthetic appeal, abrasion resistance, and fabric strength, these properties permitting use of the fabric in wall cover applications.
BACKGROUND OF THE INVENTION
[0003] Significant quantities of textile fabric are employed in the construction of domestic and business furnishings, room dividers and acoustic panels. Manufactures of such textile fabrics are cognizant of the end-use of their materials in these constructions and have looked to improve the aesthetic qualities of the fabrics. Further, manufactures have also taken safety into consideration and looked to ways in which the textile fabric can be imparted with improved levels of flame retardancy.
[0004] The production of conventional textile fabrics is known to be a complex, multi-step process. The production of fabrics from staple fibers begins with the carding process where the fibers are opened and aligned into a feedstock known as sliver. Several strands of sliver are then drawn multiple times on drawing frames to further align the fibers, blend, improve uniformity as well as reduce the diameter of the sliver. The drawn sliver is then fed into a roving frame to produce roving by further reducing its diameter as well as imparting a slight false twist. The roving is then fed into the spinning frame where it is spun into yarn. The yarns are next placed onto a winder where they are transferred into larger packages. The yarn is then ready to be used to create a fabric.
[0005] For a woven fabric, the yarns are designated for specific use as warp or fill yarns. The fill yarn packages (which run in the cross direction and are known as picks) are taken straight to the loom for weaving. The warp yarns (which run on in the machine direction and are known as ends) must be further processed. The packages of warp yarns are used to build a warp beam. Here the packages are placed onto a warper, which feeds multiple yarn ends onto the beam in a parallel array. The warp beam yarns are then run through a slasher where a water-soluble sizing is applied to the yarns to stiffen them and improve abrasion resistance during the remainder of the weaving process. The yarns are wound onto a loom beam as they exit the slasher, which is then mounted onto the back of the loom. Here the warp and fill yarns are interwoven in a complex process to produce yardages of textile fabric.
[0006] In contrast, the production of nonwoven fabrics from staple fibers is known to be more efficient than traditional textile processes as the fabrics are produced directly from the carding process with a topical treatment of the nonwoven fabric readily being applied.
[0007] Nonwoven fabrics are suitable for use in a wide-variety of applications where the efficiency with which the fabrics can be manufactured provides a significant economic advantage for these fabrics versus traditional textiles. However, nonwoven fabrics have commonly been disadvantaged when fabric properties are compared, particularly in terms of surface abrasion, pilling and durability in multiple-use applications. Hydroentangled fabrics have been developed with improved properties, which are a result of the entanglement of the fibers or filaments in the fabric providing improved fabric integrity. Subsequent to entanglement, fabric durability can be further enhanced by the application of binder compositions and/or by thermal stabilization of the entangled fibrous matrix. However, the use of such means to obtain fabric durability comes at the cost of a stiffer and less appealing fabric.
[0008] The resulting textile or nonwoven fabric requires further processing before a suitable material is available for the construction of furnishings. Fabric constructed by either mechanism is essentially planar, having little in way of macroscopic asperities, let alone, a three-dimensional aesthetic quality. It has been necessary in the art to further treat the fabric with embossing techniques or complex foaming agents in order to impart the fabric with a multi-planar, aesthetic quality. In addition, depending upon whether or not the textile fabric was woven from costly flame-retardant staple fiber, a subsequent topical treatment containing an appropriate flame-retardant chemistry is required.
[0009] U.S. Pat. No. 3,485,706, to Evans, hereby incorporated by reference, discloses processes for effecting hydroentanglement of nonwoven fabrics. More recently, hydroentanglement techniques have been developed which impart images or patterns to the entangled fabric by effecting hydroentanglement on three-dimensional image transfer devices. Such three-dimensional image transfer devices are disclosed in U.S. Pat. No. 5,098,764, hereby incorporated by reference, with the use of such image transfer devices being desirable for providing a fabric with enhanced physical properties as well as an aesthetically pleasing appearance.
[0010] In preparing an imaged nonwoven material by the present invention for use in furnishings, the material has also been found to have inherent physical properties that render the material eminently suitable for wall coverings, window coverings, upholstery, and drapery applications, which are hereby referenced as co-pending applications.
[0011] Heretofore, attempts have been made to develop flame-retardant nonwoven fabrics exhibiting the necessary aesthetic and physical properties for durable consumer applications.
[0012] U.S. Pat. No. 4,320,163, to Schwartz, hereby incorporated by reference, discloses a three-dimensional ceiling board facing. This patent contemplates selectively coating a flame-retardant substrate with a print paste consisting of a foamable plastisol. By then exposing said-coated substrate to an elevated temperature, the plastisol increases variably in height under the influence of expanding thermoplastic microspheres, forming a roughened or “pebbled” surface.
[0013] A construct is disclosed in U.S. Pat. No. 4,830,897, to Seward, whereby an initial woven textile fabrics receives thereupon a heat dissipating metallic foil followed by a fibrous batt. The application of a subsequent mechanical needling procedure integrates the layers into a unitary construct.
[0014] There are a number of Japanese patents directed to nonwoven fabrics used as a component in wall covering fabrication. JP10168756 to Kawano, et al., utilizes a flame-retardant spunbond containing diguanidine phosphate laminated to a wallpaper backing. A wallpaper is disclosed in JP10131097 to Takeuchi, et al., whereby a nonowoven fabric is adhesively bonded to wallpaper backing, the adhesive containing a significant amount of a high specific gravity fireproofing agent. JP3251452 to Nakakawara, et al., discloses an alternate foam texturing process wherein a uniform foam layer is initially applied to a nonwoven substrate, then a solvent is printed thereon to reductively pattern the laminate. A final patent of interest is JP11335958 to Nanbae, et al., whereby a two layered nonwoven fabric, each layer consisting of less than 20% thermally fusible fibers is subjected to an embossing process.
[0015] As can be seen in the prior art, there has not been an effective melding of three-dimensional aesthetic qualities with flame-retardant properties in a fabric suitable for furnishing, window covering, and wall covering applications.
SUMMARY OF THE INVENTION
[0016] In accordance with the present invention, a method of making a nonwoven fabric embodying the present invention includes the steps of providing a precursor web comprising a fibrous matrix. While use of staple length fibers is typical, the fibrous matrix may comprise substantially continuous filaments and combinations thereof. In a particularly preferred form, a staple length fibrous matrix is carded and cross-lapped to form a precursor web. It is also preferred that the precursor web be subjected to pre-entangling on a foraminous forming surface prior to imaging and patterning.
[0017] The present method further contemplates the provision of a three-dimensional image transfer device having a movable imaging surface. In a typical configuration, the image transfer device may comprise a drum-like apparatus that is rotatable with respect to one or more hydroentangling manifolds.
[0018] The precursor web is advanced onto the imaging surface of the image transfer device so that the web moves together with the imaging surface. Hydroentanglement of the precursor web is effected to form an imaged and patterned fabric.
[0019] After hydroentanglement, the imaged and patterned fabric is treated with a flame-retardant binder composition. The treated and imaged nonwoven fabric may then be subjected to one or more variety of post-entanglement treatments. Such treatments include dyeing of the fabric by conventional textile dyeing methods.
[0020] A method of making the present durable nonwoven fabric comprises the steps of providing a precursor web that is subjected to hydroentangling. Fibrous precursor webs, in either homogeneous form or in a blend with other polymeric and/or natural fibers or webs, have been found to desirably yield soft hand and good fabric drapeability. The precursor web is formed into an imaged and patterned nonwoven fabric by hydroentanglement on a three-dimensional image transfer device. The image transfer device defines three-dimensional elements against which the precursor web is forced during hydroentangling, whereby the fibrous constituents of the web are imaged and patterned by movement into regions between the three-dimensional elements of the transfer device.
[0021] In the preferred form, the precursor web is hydroentangled on a foraminous surface prior to hydroentangling on the image transfer device. This pre-entangling of the precursor web acts to partially integrate the fibrous components of the web, but does not impart imaging and patterning as can be achieved through the use of the three-dimensional image transfer device.
[0022] After hydroentangling, the imaged and patterned nonwoven fabric is treated with a flame-retardant binder finish to lend further integrity to the fabric structure. The polymeric binder composition is selected to enhance flame-retardancy and durability characteristics of the fabric, while maintaining the desired softness and drapeability of the patterned and imaged fabric.
[0023] Other features and advantages of the present invention will become readily apparent from the following detailed description, the accompanying drawings, and the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0024] The invention will be more easily understood by a detailed explanation of the invention including drawings. Accordingly, drawings, which are particularly suited for explaining the invention, are attached herewith; however, it should be understood that such drawings are for explanation purposes only and are not necessarily to scale. The drawings are briefly described as follows:
[0025] FIG. 1 is a diagrammatic view of an apparatus for manufacturing a durable nonwoven fabric, embodying the principles of the present invention;
[0026] FIG. 2 is a diagrammatic view of an apparatus for the application of a flame-retardant finish onto a nonwoven fabric, embodying the principles of the present invention;
[0027] FIG. 3 is a fragmentary top plan view of a three-dimensional image transfer device of the type used for practicing the present invention, referred to as “slubs”;
[0028] FIG. 4 is a fragmentary top plan view of a three-dimensional image transfer device of the type used for practicing the present invention, referred to as “cross slubs”;
[0029] FIG. 5 is a photograph of the resultant material utilizing the image transfer device depicted in FIG. 3 ; and
[0030] FIG. 6 is a photograph of the resultant material utilizing the image transfer device depicted in FIG. 5 .
DETAILED DESCRIPTION
[0031] While the present invention is susceptible of embodiment in various forms, there is shown in the drawings and will hereinafter be described a presently preferred embodiment of the invention, with the understanding that the present disclosure is to be considered as an exemplification of the invention, and is not intended to limit the invention to the specific embodiment illustrated.
[0032] In accordance with the present invention, a durable flame-retardant nonwoven fabric can be produced which can be employed in a wide variety of wall coverings described as applied to wallpaper. It should be understood, however, that upon suitable modification the invention can be adapted for use with cloth, wood veneer, plastic or combinations thereof, as exemplified by U.S. Pat. No. 3,663,269 to Fischer et al., hereby incorporated by reference, with the fabric exhibiting sufficient flame-retardancy, drapeability, abrasion resistance, strength, and tear resistance, with colorfastness to light. It has been difficult to develop nonwoven fabrics that achieve the desired hand, drape, and pill resistance that are inherent in woven fabrics.
[0033] In the case where nonwoven fabrics are produced using staple length fibers, the fabric typically has a degree of exposed surface fibers that will abrade or “pill” if not sufficiently entangled, and/or not treated with the appropriate polymer chemistries subsequent to hydroentanglement. The present invention provides a finished fabric that can be conveniently cut, sewn, and packaged for retail sale or utilized as a component in the fabrication of a more complex article. The cost associated with designing/weaving, fabric preparation, dyeing and finishing steps can be desirably reduced.
[0034] With reference to FIG. 1 , therein is illustrated an apparatus for practicing the present method for forming a nonwoven fabric. The fabric is formed from a fibrous matrix preferably comprising staple length fibers, but it is within the purview of the present invention that different types of fibers, or fiber blends, can be employed. The fibrous matrix is preferably carded and cross-lapped to form a precursor web, designated P. In current embodiments, the precursor web comprises staple length polyester fibers, particularly polyester having an independent level of flame-retardancy.
[0035] FIG. 1 illustrates a hydroentangling apparatus for forming nonwoven fabrics in accordance with the present invention. The apparatus includes a foraminous forming surface in the form of belt 12 upon which the precursor web P is positioned for pre-entangling by entangling manifold 14 .
[0036] The entangling apparatus of FIG. 1 further includes an imaging and patterning drum 18 comprising a three-dimensional image transfer device for effecting imaging and patterning of the lightly entangled precursor web. The image transfer device includes a moveable imaging surface which moves relative to a plurality of entangling manifolds 22 which act in cooperation with three-dimensional elements defined by the imaging surface of the image transfer device to effect imaging and patterning of the fabric being formed.
[0037] Manufacture of a durable nonwoven fabric embodying the principles of the present invention is initiated by providing the precursor nonwoven web, preferably in the form of a 100% flame-retardant polyester or polyester blend. The use of the polyester desirably provides drape, which upon treatment with the specific binder formulation listed herein, results in a material with improved flame retardant properties at relatively low cost. During invention development, fibrous layers comprising flame-retardant polyester, standard polyester, p-aramid, n-aramid, melamine, and modacrylic fibers in blend ratios between about 100% by weight to 20% by weight minor component to 80% by weight major component were found effective. Such blending of the layers in the precursor web was also found to yield aesthetically pleasing color variations due to the differential absorption of dyes during the optional dyeing steps.
[0038] After formation and integration of the imaged and patterned nonwoven fabric, a flame-retardant binder finish is applied. The flame-retardant binder finish includes chemistries to render the treated fabric the ability to resist advanced thermal degradation and flame progression when exposed to combustion temperatures. A preferred chemistry employed herein is based on a halogenated derivative of a polyurethane backbone. Additional chemistries, including metallic salt extinguisants, can be used in conjunction with the halogenated polyurethane.
[0039] Upon application and curing of the flame-retardant binder finish on the imaged nonwoven fabric, the resulting fabric can be dyed by conventional textile dying methods. Various dyeing methods commonly known in the art are applicable including nip, pad, and jet, with the use of a jet apparatus and disperse dyes, as represented by U.S. Pat. No. 5,440,771 and No. 3,966,406, both hereby incorporated by reference, being most preferred.
EXAMPLES
Example 1
[0040] Using a forming apparatus as illustrated in FIG. 1 , a nonwoven fabric was made in accordance with the present invention by providing a carded, randomized precursor fibrous batt comprising Type DPL 535 flame-retardant polyester fiber, 1.5 denier by 1.5 inch staple length, as obtained from Fiber Innovation Technology of North Carolina. The web had a basis weight of 2.8 ounces per square yard (plus or minus 7%).
[0041] Prior to patterning and imaging of the precursor web, the web was entangled by a series of entangling manifolds such as diagrammatically illustrated in FIG. 1 . FIG. 1 illustrates disposition of precursor web P on a foraminous forming surface in the form of belt 12 , with the web acted upon by entangling manifolds 14 . In the present examples, each of the entangling manifolds included three each 120 micron orifices spaced at 42.3 per inch, with the manifolds successively operated at 3 strips each at 100, 300, 800 and 800 psi, at a line speed of 60 feet per minute.
[0042] The entangling apparatus of FIG. 1 further includes an imaging and patterning drum 18 comprising a three-dimensional image transfer device for effecting imaging and patterning of the now-entangled precursor web. The entangling apparatus includes a plurality of entangling manifolds 22 that act in cooperation with the three-dimensional image transfer device of drum 18 to effect patterning of the fabric. In the present example, the three entangling manifolds 22 were operated at 2800 psi, at a line speed which was the same as that used during pre-entanglement.
[0043] The three-dimensional image transfer device of drum 24 was configured as a so-called cross-slubs, as illustrated in FIG. 4 .
[0044] Subsequent to patterned hydroentanglement, the fabric was dried on three consecutive steam cans at about 275° F., then received a substantially uniform application by dip and nip saturation of a flame-retardant binder composition at application station 40 in FIG. 2 . The web was then directed through three consecutive steam cans 41 , operated at about 250° F.
[0045] In the present example, the pre-dye finish composition was applied at a line speed of 60 feet per minute, with a nip pressure of 32 pounds per square inch and percent wet pick up of approximately 125%.
[0046] The flame retardant finish formulation, by weight percent of bath, was as follows:
Water 90% Vycar 460 × 46 [vinyl chloride acrylic co-polymer binder] 10%
[0047] As is registered to and can be obtained from B.F. Goodrich of Akron, Ohio.
Example 2
[0048] A fabric as made in the manner described in EXAMPLE 1, whereby in the alternative the flame-retardant binder composition formulation, by weight percent of bath, was as follows:
Chemwet MQ-2 [wetting agent] 0.25% Defoam 525 [silicone anti-foam] 0.25% Pyron 6135 [halogenated polyurethane] 16.0% Chemonic TH-22 [thickener] 1.0%
[0049] The above being registered to and can be obtained from Chemonic Industries, of North Carolina.
Ammonium hydroxide, Aqueous 0.50%
[0050] As is registered to and can be obtained from B.F. Goodrich, of Ohio
Water 82.0%
Example 3
[0051] A fabric as made in the manner described in EXAMPLE 1, whereby in the alternative 20.0% Pyron 6139 was used in place of 16% Pyron 6135 and 78.0% water was used in place of 82.0% water.
[0052] The following benchmarks have been established in connection with nonwoven fabrics, which exhibit the desired combination of durability, softness, abrasion resistance, etc., for certain home use applications.
Vertical Flame Test NFPA-701 Fabric Strength/Elongation ASTM D5034 Absorbency -- Capacity ASTM D1117 Elmendorf Tear ASTM D5734 Handle-o-meter ASTM D2923 Stiffness -- Cantilever Bend ASTM D5732 Fabric Weight ASTM D3776 Martindale Abrasion Test ASTM D4970 Colorfastness To Crocking AATCC 8-1988
[0053] The test data in the attached tables shows that nonwoven fabrics approaching, meeting, or exceeding the various above-described benchmarks for fabric performance in general, and to commercially available products in specific, can be achieved with fabrics formed in accordance with the present invention. For many applications, fabrics having basis weights between about 2.0 ounces per square yard and 6.0 ounces per square yard are preferred, with fabrics having basis weights of about 2.5 ounces per square yard to about 3.5 ounces per square yard being most preferred. Fabrics formed in accordance with the present invention are flame-retardant, durable and drapeable and are suitable for decorative wall cover applications.
[0054] For upholstery and drapery applications, fabrics having basis weights between about 2.0 ounces per square yard and 10.0 ounces per square yard are preferred, with fabrics having basis weights of about 3.0 ounces per square yard to about 6.0 ounces per square yard being most preferred. Fabrics formed in accordance with the present invention are flame-retardant, durable and drapeable, and are not only suitable for covering or upholstering furniture such as chairs, couches, love seats, and the like, but also draperies or hanging fabric that prevents the admittance of any ambient light through the fabric.
[0055] For window covering applications, fabrics having basis weights between about 0.5 ounces per square yard and 6.0 ounces per square yard are preferred, with fabrics having basis weights of about 1.0 ounces per square yard to about 4.0 ounces per square yard being most preferred. Fabrics formed in accordance with the present invention are flame-retardant, durable and drapeable, and are suitable for window covering applications. Window coverings of the present invention are those coverings that allow for the admittance of ambient light through the fabric, such as sheets, shades, or blinds including, but not limited to cellular, vertical, roman, soft vertical, and soft horizontal.
[0056] From the foregoing, it will be observed that numerous modifications and variations can be affected without departing from the true spirit and scope of the novel concept of the present invention. It is to be understood that no limitation with respect to the specific embodiments illustrated herein is intended or should be inferred. The disclosure is intended to cover, by the appended claims, all such modifications as fall within the scope of the claims. | A method of forming flame-retardant nonwoven fabrics by hydroentanglement includes providing a precursor web. The precursor web is subjected to hydroentanglement on a three-dimensional image transfer device to create a patterned and imaged fabric. Treatment with a flame-retardant binder enhances the integrity of the fabric, permitting the nonwoven to exhibit desired physical characteristics, including strength, durability, softness, and drapeability. The treated nonwoven may then be dyed by means applicable to conventional wovens. | 3 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a method for the manufacture of arsenious anhydride (As 2 O 3 ) from a substance containing arsenic sulfide.
2. Description of the Prior Art
Arsenic (As) which is contained in waste water is prevalently removed therefrom by being precipitated in the form of arsenic sulfide containing substance also (As 2 S 3 ). The recovered arsenic sulfide generally contains impurities.
A method generally followed in producing arsenious anhydride from such an arsenic sulfide-containing substance comprises extracting arsenic from the arsenic sulfide-containing substance into a copper sulfate-containing aqueous solution at an elevated temperature by use of an autoclave, thereby obtaining a solution containing arsenious acid in nearly a saturated concentration, and subsequently cooling the produced solution, thereby crystallizing the arsenious anhydride therein, and recovering the crystallized arsenious anhydride.
This method has the disadvantage that the procedure involved is dangerous because copper sulfide and solid impurities must be separated from the produced solution at an elevated temperature and the raw material requires careful selection or the produced arsenious anhydride will require repurification because impurities may possibly be crystallized simultaneously with the arsenious anhydride owing to the cooling method employed for the crystallization.
This disadvantage may be precluded by a method which comprises obtaining a solution containing arsenious acid in a low concentration, cooling this solution, removing copper sulfide and solid impurities, subsequently concentrating the remaining solution, by evaporation, and cooling the solution thereby crystallizing arsenious anhydride therein (as disclosed in JA-OS No. 54699/1977 laid open for public inspection in May 4, 1977, for example). However, this method has the disadvantage that the volumes of solutions to be treated are increased and the concentration of such solutions requires a large amount of thermal energy.
SUMMARY OF THE INVENTION
An object of this invention is to provide a method which overcomes the disadvantage described above and permits arsenious anhydride of high purity to be produced at a low cost.
The inventors made a diligent study with a view to attaining the object described above. They consequently found that when a solution or solid containing arsenious acid is subjected to aeration in the presence of copper ions, the elemental of arsenic is oxidized from its trivalent form into a pentavalent form. On the basis of this discovery, they have perfected a method for the manufacture of arsenious anhydride, which comprises extracting arsenic from an arsenic sulfide-containing substance into an aqueous solution containing copper sulfate, oxidizing the greater part of the arsenious acid present in the extract into arsenic acid, filtering the extraction residue containing copper sulfide and solid impurities, and subsequently weakly reducing the filtrate, thereby crystallizing arsenious anhydride therein for subsequent recovery.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a graph showing the solubilities of As 2 O 3 ,As 2 O 5 .4H 2 O and As 2 O 5 .5/3H 2 O.
FIG. 2 is a graph showing the saturated concentrations of As III and As V calculated from the values of solubilities of FIG. 1.
DETAILED DESCRIPTION OF THE INVENTION
By the first method of this invention, arsenious anhydride is manufactured by causing the aeration performed for the extraction of arsenic from the arsenic sulfide-containing substance into the aqueous solution containing copper sulfate to be carried out in the presence of at least 1 g of copper ions per liter, thereby simultaneously effecting the extraction of arsenic and oxidation of the greater part of the arsenious acid in the extract into arsenic acid, filtrating the extraction residue, applying a weak reducing agent to the resultant filtrate, thereby reducing arsenic acid in the solution into arsenious acid and crystallizing arsenious anhydride therein for subsequent recovery.
When a powdered arsenic sulfide-containing substance is repulped in the form of slurry in an aqueous solution containing copper sulfate and the resultant mixture is stirred and heated to a temperature of at least 50° C., preferably to the level of 90° C., the arsenic is extracted as indicated by the following formula.
As.sub.2 S.sub.3 +3CuSO.sub.4 +3H.sub.2 O→As.sub.2 O.sub.3 +3CuS+3H.sub.2 SO.sub.4
Since the solubility of As 2 O 3 is not very high, As 2 O 3 is crystallized in the slurry when the amount of arsenic to be extracted is large. This crystallization of As 2 O 3 , however, offers no appreciable hindrance to the reaction of extraction.
By the second method of this invention, arsenious anhydride is manufactured by extracting arsenic from the arsenic sulfide-containing substance into an aqueous solution containing copper sulfate, cooling the extract containing the extraction residue, thereby recovering solids containing arsenious anhydride, repulping the recovered solids, subjecting the resultant slurry to aeration in the presence of at least 1 g of copper ions per liter, thereby oxidizing the greater part of the arsenious acid into arsenic acid, filtering the residue, and subsequently adding a weak reducing agent to the filtrate, thereby crystallizing the arsenious anhydride therein, and recovering the anhydride.
After the reaction of extraction involved in the second method described above, the slurry is cooled to a level near room temperature to effect solid-liquid separation and recover solids containing arsenious anhydride, copper sulfide precipitate and solid impurities, and the resultant fitrate is subjected to a waste water treatment. This process is required for the following reason. As indicated by the reaction formula shown above, free sulfuric acid accumulates in the reaction system with the progress of the extraction of arsenic. When the concentration of the free sulfuric acid exceeds a particular level (about 70 g/lit.), the accumulated free sulfuric acid begins to hold down the oxidation of arsenious acid and proves to be a great hindrance to the production of an arsenic acid solution of high concentration. By the performance of this process, free sulfuric acid is expelled out of the reaction system. Since the solution thus expelled has a small amount of arsenious acid dissolved therein, it is subjected first to a treatment for the removal of arsenic and then to a treatment for neutralization. The arsenic-containing substance which is recovered here may be used as the raw material for the operation of this invention.
The solids which are recovered in the course of the process described above are repulped in an aqueous solution containing copper sulfate and converted into a slurry. This slurry is heated to a temperature of at least 20° C., preferably to a level of about 80° C., and aerated as by means of turbo agitation. Consequently, arsenious acid contained therein is oxidized into arsenic acid.
In this method, the extract is cooled to room temperature to effect solid-liquid separation. Optionally, this separation may be carried out by the process of flotation instead. To be specific, the separation may be effected by a procedure which comprises diluting the slurry obtained after the extraction to a concentration suitable for flotation (below 300 g/liter), preferably to a concentration of 100 to 200 g/liter, by addition of a small amount of water or an aqueous solution containing arsenic (desirably an aqueous solution saturated with arsenic), causing arsenious acid to float to the surface of the slurry by blowing air into the diluted slurry or subjecting the slurry to flotation, and separating the floating crude arsenious anhydride for recovery.
During this flotation process, reagents such as pine oil and methylisobutyl carbinol (M.I.B.C.) which are generally used in the flotation process may be used in ordinary amounts (on the range of 1 g to 100 g per ton of the substance under treatment).
In either of the two methods described above, copper ions and copper sulfide are believed to function as a catalyst. The copper ions sufficiently fulfill the purpose when they are present in concentration of at least 1 g/liter. If the copper ions are present in an excess, they go to adhere to arsenious anhydride and degrade the purity. For practical purpose, therefore, they are desired to be present in a concentration of 5 to 40 g/liter, preferably around 30 g/liter.
The reaction of oxidation of arsenious acid to arsenic acid proceeds rather slowly. By suitably selecting the reaction time, the ratio of arsenious acid to arsenic acid can be freely controlled. Normally, the greater part of the arsenic is converted into arsenic acid. If the solution contains impurities which are readily coprecipitable with arsenious anhydride, it is allowed to retain therein arsenious acid in a concentration slightly exceeding the solubility thereof. When this solution is cooled, the impurities can be removed simultaneously with the small amount of arsenious anhydride. In this manner, the purity of the arsenious anhydride to be finally obtained can be heightened.
The conversion of the greater part of arsenic present in the solution to arsenic acid brings about the following advantages. The first advantage is that the conversion gives a solution containing arsenic in a higher concentration because the solubility of arsenic acid is greater than that of arsenious acid. It is only natural that the efficiency of the crystallization of arsenious anhydride heightens in proportion as the concentration of arsenic increases. Consequently, the equipment to be used for the extraction and crystallization can be decreased in size and the cost of equipment can be lowered.
The second advantage is that the necessity for keeping the temperature at constant level during the step of filtration is obviated because arsenic acid or arsenious acid is not crystallized by mere cooling when the greater part of arsenic is converted in the form of unsaturated arsenic acid. Optionally, the dissolved impurities in the solution may be crystallized and removed by cooling.
FIG. 1 shows the solubilities of arsenious anhydride (As 2 O 3 ) and arsenic acids (As 2 O 5 .4H 2 O and As 2 O 5 .5/3H 2 O). FIG. 2 shows the saturated concentrations of trivalent arsenic (As III ) and pentavalent arsenic (As V ) calculated from the numerical values of solubility of FIG. 1. The description given above will be understood easily from these graphs.
The aqueous solution containing copper sulfate which is used in this invention may contain a small amount of impurities. For example, the leached liquor of precipitated copper or the electrolytic decopperized slime with sulfuric acid, or the mother liquor remaining after the recovery of arsenious anhydride in the final step of the method of this invention may be used.
When the slurry obtained by the aforementioned step of oxidation is subjected to solid-liquid separation, there is obtained a solution containing arsenic in the form of arsenic acid. When a weak reducing agent is applied to this solution, the arsenic acid is reduced to arsenious acid and the portion of arsenious acid exceeding the amount of solubility is crystallized in the form of arsenious anhydride. As the reducing agent, sulfur dioxide is advantageously used.
The process of extraction described above proceeds at a low speed at a low temperature. The extraction, therefore, is desired to be carried out at a temperature in the range of 50° to 100° C.
The extraction residue which contains copper sulfide can be used as the raw material for the copper smelting.
As described above, all the steps of the method of this invention can be performed under normal atmospheric pressure at temperatures not exceeding 100° C. And a solution having a high arsenic concentration can be obtained without being concentrated by evaporation. The method of this invention, therefore, is highly advantageous from the standpoint of cost. Further, the method of this invention has the advantage that it can produce arsenious anhydride having a lower content of impurities than the method of crystallization by cooling because the crystallization of arsenious anhydride in the final step can be carried out at a relatively high temperature.
Now, examples of this invention and a comparative experiment will be described.
EXAMPLE 1
In an aqueous solution obtained by dissolving 800 g of crystalline copper sulfate in 2 liters of water, 1.5 kg of an arsenic sulfide-containing substance (having a water content of 80%) was stirred at 80° C. for five hours to effect extraction and oxidation of arsenic. Then, the mixture was cooled to 60° C. About 600 g of extraction residue was filtered off.
Three (3) liters of the extract thus obtained was cooled to room temperature. By blowing sulfur dioxide into the cooled extract, the arsenic acid was reduced. Consequently, there was obtained 92 g of arsenic anhydride.
The composition of the arsenic sulfide-containing substance, that of the copper sulfate solution, that of the extraction residue, that of the extract, and that of arsenious anhydride are shown in Table 1. The purity of the produced arsenious anhydride was 99.6% by weight.
EXAMPLE 2
Two hundred (200) g of electrolytic decopperized slime (on wet basis) was heated with dilute sulfuric acid, aerated, and extracted. In 2 liters of the resultant aqueous copper sulfate solution, 400 g of crystalline copper sulfate was dissolved. The resultant solution was mixed with 1.5 kg of the same arsenic sulfide-containing substance as used in Example 1 (having a water content of 80%). By following the procedure of Example 1, the resultant mixture was subjected to extraction, the extraction residue was separated by filtration, and the filtrate was subjected to a reducing treatment. Consequently, there was obtained about 600 g of extraction residue and 170 g of arsenious anhydride.
The composition of the arsenic sulfide-containing substance, that of the copper sulfate-containing solution, that of the extraction residue, that of the extract, and that of arsenious anhydride are shown in Table 2. The purity of the produced arsenious anhydride was 99.3% by weight.
EXAMPLE 3
Four hundred (400) g of electrolytic decopperized slime (on wet basis) was heated with dilute sulfuric acid, aerated, and extracted. In 2 liters of the resultant aqueous copper sulfate solution, 1.5 kg of the same arsenic sulfide-containing substance as used in Example 1 (having a water content of 80%) was mixed, the resultant mixture was stirred and heated at 80° C. for three hours to effect extraction and oxidation of arsenic. The mixture was cooled to 60° C. and, thereafter, about 600 g of extraction residue was separated by filtration.
When the extract thus obtained was cooled to room temperature, part of the arsenious acid was crystallized as arsenious anhydride.
The crystallized arsenious anhydride was separated by filtration. When sulfur dioxide was blown into the filtrate, the arsenic acid was reduced. Consequently, 270 g of arsenious anhydride was crystallized and recovered.
The composition of the arsenic sulfide-containing substance, that of the copper sulfate-containing solution, that of the extraction residue, that of the extract, that of the extract obtained after cooling and separation by filtration, and that of the finally obtained arsenious anhydride are shown in Table 3. The purity of the produced arsenious anhydride was 99.6% by weight.
The main impurity in the arsenious anhydride obtained in Example 2 was antimony. In Example 3, since arsenious acid was allowed to remain in an amount slightly exceeding the solubility in the steps of extraction and oxidation of arsenic, a small amount of arsenious anhydride was crystallized when the reaction system was cooled to room temperature. Since antimony was coprecipitated with this arsenious anhydride, the antimony concentration in the extract could be lowered proportionally. As the result, the antimony content in the finally obtained arsenious anhydride was lowered to about one fifth of the level in the arsenious anhydride of Example 2. Thus, the purity of the produced arsenious anhydride could be heightened.
TABLE 1__________________________________________________________________________Arsenic sulfide-containing Copper sulfate Extraction Extract after Arsenioussubstance containing residue cooling and anhydride1.5 Kg Solution 600 g Extract separation by 92 g(% by 2 l (% by 3 l filtration (% byweight) (g) (g/l) (g) weight) (g) (g/l) (g) (g/l) (g) weight)__________________________________________________________________________Cu 0.05 0.15 102.4 204.8 61.7 185.1 5.0 15.0 -- -- 0.0002As.sup.III -- -- 2.5 7.5 -- -- As.sub.2 O.sub.3 99.6 40.0 120 2.5 7.5As.sup.V -- -- 35.0 105.0 -- --Sb 0.08 0.24 -- -- 0.01 0.03 0.05 0.15 -- -- 0.22Bi <0.01 -- -- -- -- -- -- -- -- -- --Fe 0.34 1.02 -- -- -- -- 0.34 1.02 -- -- 0.0002Zn 6.00 18.00 -- -- -- -- 6.00 18.00 -- -- 0.0003H.sub.2 O 80 / -- / 50 / -- / -- / 5.0__________________________________________________________________________
TABLE 2__________________________________________________________________________Arsenic sulfide-containing Copper sulfate Extraction Extract after Arsenioussubstance containing residue cooling and anhydride1.5 Kg solution 600 g Extract separation by 170 g(% by 2 l (% by 3 l filtration (% byweight) (g) (g/l) (g) weight) (g) (g/l) (g) (g/l) (g) weight)__________________________________________________________________________Cu 0.05 0.15 102.2 204.4 62.3 186.9 5.0 15.0 -- -- 0.0003As.sup.III 2.9 8.7 -- -- As.sub.2 O.sub.3 99.3 40.0 120 35.6 71.2 3.5 10.5As.sup.V 55.0 165.0 -- --Sb 0.08 0.24 0.85 1.7 0.20 0.6 0.40 1.20 -- -- 0.48Bi <0.01 -- 0.057 0.114 0.04 0.12 -- -- -- -- --Fe 0.34 1.02 0.043 0.086 -- -- 0.39 1.17 -- -- 0.0002Zn 6.00 18.00 0.028 0.056 -- -- 6.0 18.0 -- -- 0.0002H.sub.2 O 80 / -- / 50 / -- / -- / 7.5__________________________________________________________________________
TABLE 3__________________________________________________________________________Arsenic sulfide-containing Copper sulfate Extract Extract after Arsenioussubstance containing residue cooling and anhydride1.5 Kg solution 600 g Extract separation by 270 g(% by 2 l (% by 3 l filtration (% byweight) (g) (g/l) (g) weight) (g) (g/l) (g) (g/l) (g) weight)__________________________________________________________________________Cu 0.05 0.15 102 204 63.0 189.0 5.0 15.0 5.0 15.0 0.0005As.sup.III 18.5 55.5 15.0 45.0 As.sub.2 O.sub.3 99.6 40.0 120 71.2 142.4 4.0 12.0As.sup.V 65.0 195.0 65.0 195.0Sb 0.08 0.24 1.70 3.4 0.4 1.2 0.81 2.43 0.08 0.24 0.1Bi <0.01 -- 0.114 0.228 0.08 0.24 -- -- -- -- --Fe 0.34 1.02 0.086 0.172 -- -- 0.40 1.20 0.40 1.20 0.0002Zn 6.00 18.00 0.056 0.112 -- -- 6.04 18.12 6.04 18.12 0.0003H.sub.2 O 80 / -- / 50 / -- / -- / 5.0__________________________________________________________________________
EXAMPLE 4
With 400 liters of a solution containing 15.5 g of As III , 13.2 g of As V , 32.6 g of Cu, 0.14 g of Sb, 0.52 g of Ca, and 89.5 g of free sulfuric acid respectively per liter and 100 liters of water, 700 kg of an arsenic sulfide precipitate [39.7% of As, 0.12% of Sb, 0.18% of Fe, 4.03% of Zn, 4.17% of Ca, and 78.2% of water respectively by weight (on dry basis)] was converted into slurry. This slurry was mixed with 360 kg of crystalline copper sulfate. The resultant mixture was heated to 85° C. and stirred for two hours to effect extraction. The stirred hot slurry was cooled to room temperature to effect solid-liquid separation. Consequently, there were obtained 567 kg of solids (wet weight) and 100 liters of solution. This solution was analyzed. The analyses are shown in Table 4.
TABLE 4______________________________________ Free sulfuricTotal As Cu Sb Ca acid______________________________________Content 13.4 11.2 0.008 0.60 107(g/liter)______________________________________
With 400 liters of a solution containing 12.5 g of As III , 5.09 g of As V , 34.0 g of Cu, 0.16 g of Sb, 0.53 g of Ca, and 91.1 g of free sulfuric acid respectively per liter and 630 liters of a solution containing 4.3 g of As III , 17.1 g of As V , 12.0 g of Cu, 0.054 g of Sb, 0.54 g of Ca, and 29.8 g of free sulfuric acid respectively per liter, 567 kg of said solids were converted into slurry. This slurry was mixed with 110 kg of crystalline copper sulfate. The resultant mixture was heated to 80° C. and aerated by turbo agitation for 7.5 hours. The slurry was then cooled to room temperature to effect solid-liquid separation. Consequently, there were obtained 438 kg of residue (wet weight) and 982 liters of an arsenic acid-containing solution.
The residue and the arsenic acid-containing solution were analyzed. The analyses are shown in Table 5 and Table 6.
TABLE 5______________________________________Residue As Cu Sb Ca Zn H.sub.2 O______________________________________Content (% by weight 3.73 48.4 0.07 2.70 0.10 60.8on dry basis)______________________________________
TABLE 6______________________________________Arsenic acid-containing solution Free sulfuricAs.sup.III As.sup.V Cu Sb Ca acid______________________________________Content 12.4 58.8 41.0 0.23 0.51 82.9(g/liter)______________________________________
By blowing sulfur dioxide into the produced arsenic acid-containing solution thereby reducing the arsenic acid, arsenious anhydride was crystallized. Consequently, 67.7 kg of arsenious anhydride was recovered. The analysis of the produced arsenious anhydride are shown in Table 7.
TABLE 7__________________________________________________________________________ As.sub.2 O.sub.3 Cu Sb Bi Fe Si Pb Ca Zn H.sub.2 O__________________________________________________________________________Content 99.9 0.0011 0.064 0.0002 <0.0001 <0.001 <0.0001 <0.0001 <0.0001 <0.1(% by weight)__________________________________________________________________________
It is apparent from the comparison of the composition of Table 6 with that of undermentioned Table 8 that the reaction of As III →As V proceeded at a higher velocity. It will be readily noted that this high reaction velocity was ascribable to the concentration of free sulfuric acid.
COMPARATIVE EXPERIMENT
With 700 liter of water, 390 kg of arsenic sulfide precipitate [39.7% of As, 0.12% of Sb, 0.18% of Fe, 4.03% of Zn, 4.17% of Ca, 78.2% of water respectively by weight (on dry basis)] was converted into slurry. This slurry was mixed with 420 kg of crystalline copper sulfate and the resultant mixture was heated at 80° C. and aerated by turbo agitation for 11 hours and subsequently subjected to solid-liquid separation at 60° C. The resultant solution (800 liters) was analyzed. The analyses are shown in Table 8.
TABLE 8______________________________________ Free As.sup.III As.sup.V Cu Ca sulfuric acid______________________________________Content 26.0 34.8 35.6 0.97 136(g/liter)______________________________________
It is noted from Table 8 that the oxidation of As III to As V occurred insufficiently. | Arsenic anhydride of high purity is inexpensively manufactured from an arsenic sulfide-containing substance by first contacting the arsenic sulfide-containing substance with a copper sulfate-containing aqueous solution so as to provide an extract solution containing arsenious acid, the extract solution is subjected to aeration in the presence of copper ions such that the arsenious acid therein is mostly oxidized to arsenic acid, the thus provided treated solution is subjected to a weak reducing agent to cause crystals of arsenious anhydride to form, and these crystals are then recovered. Alternatively, the extract solution is cooled to recover a solid precipitate containing arsenious anhydride, these solids are repulped into a slurry, the slurry subjected to aeration in the presence of copper ions such that the arsenious acid therein is mostly oxidized to arsenic acid, the thus provided treated solution is subjected to a weak reducing agent to cause crystals of arsenious anhydride to form, and these crystals are then recovered. | 2 |
TECHNICAL FIELD
This invention relates to apparatus and a method for the lubrication of expansible chamber devices of the type having a cylinder with a piston reciprocating therein and a fluid flowing in and out of the chamber. The apparatus and method of the present invention is particularly useful for lubricating the displacer piston, the power piston or both in a free piston Stirling engine.
BACKGROUND OF THE INVENTION
One major advantage of the free piston Stirling engine is that the working gas can be entirely sealed within the engine to prevent its contamination or loss by leakage. It is undesirble to lubricate the pistons of the free piston Stirling engine with traditional lubricants, such as petroleum based oil and grease, because such lubricants vaporize into the working gas and reduce its efficiency.
Nonetheless, it is still desirable to lubricate such engines for the purpose of extending the life of the engine and reducing its wear and maintenance.
It is therefore an object of the present invention to effect the hydrodynamic lubrication of pistons through use of the fluids which act upon or are acted upon by the pistons in the operation of the device, and particularly to lubricate the pistons of Stirling engines with the working gas of the engine.
BRIEF DISCLOSURE OF THE INVENTION
In the present invention a torque force is applied to the piston to cause it to spin at a sufficient angular velocity that it will entrain and drag along its outer surface some of the fluid which acts upon or is acted upon by the piston. This layer of fluid separates the interfacing and relatively sliding surfaces of the piston and its associated cylinder.
In particular, the torque is applied by creating a turbine effect during the intake or exhaust of the fluid. The torque is applied to the piston by impinging a flowing stream of the fluid on the piston as the fluid enters or leaves the expansible chamber in a manner which creates a turbine effect urging the piston to spin.
Desirably, inlet or outlet ports are formed through the cylinder about the piston or pistons. Turbine surfaces, such as blades or the walls of slots are formed in and spaced around the pistons. The ports are positioned so that during the normal operation of the device, the fluid will flow through the port and periodically impinge upon the turbine surfaces to apply a circumferential force component on the piston. By selected positioning of the ports in many devices, such as the free piston Stirling engine, the normal operation of the device may be maintained undisturbed while gaining the advantages of hydrodynamic lubrication in accordance with the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a diagrammatic view in axial cross section illustrating a free piston Stirling engine which embodies the invention.
FIG. 2 is a bottom view of the displacer piston illustrated in the embodiment of FIG. 1.
FIG. 3 is a top view of the power piston illustrated in the embodiment of FIG. 1.
FIG. 4 is a view in cross section of an alternative embodiment of the ports in the cylinder wall illustrating an oblique port orientation.
FIG. 5 is a graph illustrating the operation of the preferred embodiment of the invention.
FIG. 6 is a side view of an alternative displacer piston structure embodying the present invention.
FIG. 7 is a diagrammatic illustration of an alternative embodiment of the invention.
DETAILED DESCRIPTION
FIG. 1 illustrates a free piston Stirling engine having a displacer piston 10 and a power piston 12 which reciprocate in a single, cooperating cylinder 14.
In the illustrated engine, heat is applied at its end 16 and withdrawn from its intermediate area 18. Therefore, the engine has its compression space 20 adjacent its cooled area 18 and its expansion space 22 adjacent its heated end 16, these spaces being formed at opposite ends of the displacer 10. The engine is provided with expansion space ports 24 which are in fluid communication with the expansion space 22 and compression space ports 26 which are in fluid communication with the compression space 20. These ports 24 and 26 are in communication with each other through a conventional regenerator 28.
The engine operates in the conventional manner as well known in the art. A working gas is contained within the expansion and compression spaces and is alternately forced into the heated expansion space 22 and the cooled compression space 20 by the displacer. The alternate heating and cooling of the working gas causes the gas to alternately expand and increase its pressure and contract and decrease its pressure. These alternate changes in pressure cause the power piston to reciprocate and also result in proper phasing of the reciprocating displacer piston. Since the fundamental operation of the free piston Stirling engine is well described in the prior art no further description is necessary here.
A plurality of inwardly extending slots 30 are arranged around the seal skirt portion 32 of the displacer piston. Similarly, a plurality of such slots 34 are arranged around the power piston 12. The inner walls of these slots form turbine surfaces against which working gas can be impinged as it flows between the compression and expansion spaces to create a turbine effect and a resulting torque on these pistons.
In the embodiment illustrated in FIG. 1 the compression space ports 26 are positioned to register with the slots 30 of the displacer piston 10 during the end of the stroke of the displacer piston 10 which is nearest or proximal to the compression space 20 and also to register with the slots 34 of the power piston at the end of its stroke which is nearest or proximal to the compression space 20.
The compression space ports 26 are positioned to direct the flowing stream of working gas upon the turbine surfaces in the slots of the pistons to impart an average torque in one direction upon the piston. As described below, the cyclical reciprocation of both pistons is such that their slots register with the ports 26 during a part of the cycle that the gas is flowing in a single direction. For example, in the embodiment illustrated, the gas impinges upon the slots 30 of the displacer piston 10 at a time in the cycle when gas is entering the compression space 20 and impinges upon the slots 34 of the power piston 12 at a time when the working gas is leaving the compression space 20 and flowing into the expansion space 22. During the registration of the slot walls of either piston with the ports, the flowing gas applies an impulse torque to the piston.
Alternatively, the displacer turbine slots may be formed at the opposite end of the displacer piston to be impinged upon by working fluid flowing into the expansion space 22. As a still further alternative, the slots may be provided at both ends of the displacer piston 10 as illustrated in FIG. 6.
The structural configuration and orientation of the ports as well as of the turbine surfaces may be modified in a great variety of ways as is well known in the turbine art. For example, the slots may be curved and/or the inlet ports may be obliquely inclined to the cylindrical wall surface in order to impart a tangential component to the fluid flow. The various alternative turbine systems are not discussed in more detail because they are well discussed in the prior turbine art.
Furthermore, the turbine surfaces may be formed on a separate structure which is attached to the piston or the piston rod. However, for purposes of this patent, because such systems are functionally equivalent to being a part of the piston, they are considered to be a part of the piston.
As a further alternative, the ports may be positioned at the end wall or walls of the chamber of a reciprocating piston, expansible chamber device and provided with suitable cooperating turbine surfaces on the piston so that the fluid flow will apply the appropriate torque force to the piston during intake or exhaust of the fluid.
As still a further alternative the ports at the walls of the cylinder may be interposed between the extremes of the piston stroke. It is not necessary that they be positioned so that all flow be in a single direction during the interval that the turbine surfaces are in registration with the fluid ports. It is only necessary that during the interval of registration there be a net or average flow in one direction or the other.
As still another alternative, the ports or the turbine surfaces may additionally have some axial spacing rather than being arranged circularly at spaced intervals. For example, the ports may be somewhat helically arranged about the cylinder to provide a broader torque impulse of longer duration.
In the embodiment of FIG. 1 it is desirable to cause the displacer piston 10 and the power piston 12 to spin in opposite direction to assure that their interfacing portions, namely the piston rod 40 and its reciprocally associated bore 42, will be rotating relative to each other. This will assure that these interfacing surfaces are also lubricated. Of course, the two could be spun in the same direction at different speeds but with less effectiveness.
To accomplish this in the embodiment illustrated in FIG. 1, the slots 30 and the slots 34 may be formed in the same direction in the operable position which will provide opposite spin torques because the working gas flows into the compression space 20 when it impinges upon the turbine surfaces 32 of the displacer piston 10 and flows out of the compression space 20 when it impinges upon the turbine surfaces 34 of the power piston 12.
The advantages of the system of the present invention wherein a fluid, which acts upon, or is acted upon a piston, is directed to cause a turbine effect which in turn imparts a spin to lubricate the piston hydrodynamically are not limited to the coaxial free piston Stirling engines.
For example, it is applicable to free piston Stirling engines in which the displacer piston and the power piston reciprocate in different cylinders. Further, it is applicable to the broader range of expansible chamber devices which have a piston which both reciprocates and is free to rotate about its axis. For example, many such piston devices have a piston which is connected by an intermediate piston or connecting rod to a crankshaft. The addition of a suitable bearing on the piston rod in such a device will enable its piston to be free for rotation in addition to reciprocation. Thus, the principles of the present invention are applicable to other engines, pumps and motors of the expansible chamber, reciprocating piston type.
FIG. 5 illustrates the operation of the embodiment of the invention illustrated in FIG. 1. Graph A of FIG. 5 is a plot representing the position of the opposing faces of the displacer piston and the power piston within the cylinder 14 as a function of time. The horizontal line P represents the position in the cylinder of the compression space ports 26. Of course, in a more detailed graph the horizontal line P actually would consist of a pair of parallel horizontal lines separated by a distance representing the width of the ports. In Graph A the more positive direction on the vertical axis represents positions nearer the hot or expansion space 22.
Whenever the displacer piston face is more negative than the horizontal line P or whenever the power piston face is more positive than the horizontal line P, the slots in the respective pistons are in registration with the compression space ports 26.
Graph B is a plot of the flow rate of the working gas with respect to time.
At point 40 in Graph A the displacer piston slots begin registration with the compression space ports 26. This registration continues until point 42. Therefore, during the time interval from points 40 to 42 a torque impulse is applied to the displacer piston by the gas which is flowing into the compression space and illustrated in the shaded area 44.
Similarly, during the time interval from point 46 to point 48 the power piston receives a torque impulse from the working gas flow illustrated in the shaded area 50.
FIG. 7 diagrammatically illustrates an alternative embodiment of the invention for use in a free piston Stirling engine in which the flowing stream of working fluid which impinges upon the turbine surfaces to impart the torque is obtained from a structure which is different from the conventional gas flow path between the hot space and the cold space. The diagram only illustrates the structures relevant to this modification and does not repeat many of the structures which are illustrated in FIG. 1.
The embodiment of FIG. 7 has a hot space 66, a cold space 68, a power piston 62 and a displacer piston 60 mounted within the cylinder 64 in the same manner as the device of FIG. 1.
However, the structure illustrated in FIG. 7 additionally is provided with a storage chamber 70 which is in communication with a port 73 or several such ports through a check valve 72. The storage chamber is also in communication with ports 74 and 76. A plurality of annularly arranged ports may be substituted for ports 74 and 76.
Whenever the port 73 is exposed by the displacer 60 and the working gas pressure in the work space is greater than the gas pressure in the storage chamber 70, working gas will flow into the storage chamber. Thus, gas flows during the high pressure part of the operating cycle into the storage chamber 70 through the check valve 72.
The ports 74 and 76 are positioned so that they will be in registration with the turbine surfaces during a relatively low pressure portion of the operating cycle. Thus, when such registration occurs, gas can flow from the storage chamber and impinge upon the turbine surfaces to impart a torque upon the pistons in a manner similar to that described above. In this manner the storage chamber 70 accumulates working fluid during the high pressure portion of the operating cycle and releases it to flow against the turbine surfaces during the lower pressure portions of the cycle. | This invention relates to a free piston Stirling engine in which a structure for aiding in the lubrication of the engine is provided. The piston of the Stirling engine is provided with turbine surfaces, such as blades. Working fluid entering the cylinder chamber applies a spin torque to the piston thereby causing the piston to spin and entrain gas about its perimeter for hydrodynamic gas lubrication. | 5 |
BACKGROUND OF THE INVENTION
This invention relates to connectors for attaching detachable electrical power cords to eIectrically powered equipment, especially to personal computers and desk-top laser printers, specifically to an improved connector that locks in place and can be detached from an electrically powered apparatus only by an authorized person. The advantage of the present invention will be realized when same is used in conjunction with other apparatus intended to prevent the use of electrically powered equipment by unauthorized users. Such other apparatus could, for instance, consist of a controlled-access means for simultaneously retaining the electrical plug of the power cord, which is connected to the invention, in a socket in said apparatus while selectively enabling and disabling the flow of electrical current thereto as desired by an authorized user. Alternatively, the power cord to which the present invention (a connector) is attached could incorporate a key-controlled means for selectively enabling and disabling the flow of electrical current through said power cord as desired by an authorized user. Thus, it will be seen that the present invention is simply a power-cord connector that can not be removed from an appliance by an unauthorized person, and that the advantage thereof will be realized only when the power cord attached to the subject connector is provided with an effective, access-controlled means for enabling and preventing the the flow of electrical current through said power cord and connector as desired by an authorized user.
Various devices have been proposed and implemented for preventing the unauthorized use of electrically powered equipment by preventing the flow of electric current through the appliance power cord. Some of these devices are lockouts that enclose the conventional power plug of the appliance cord in such a fashion that the plug can not be engaged in an electrical wall outlet. Other of these devices lock the conventional appliance cord plug into the device, provide a means for supplying electrical power to the device, and further provide a means (usually a key-controlled switch) for permitting or preventing the flow of electricity from the device to the appliance power cord. Still other of these devices utilize a specially designed cord plug that looks into a mating specially designed power outlet to control the availability of electrical current to the power cord.
The number of embodiments proposed and implemented of such locking devices suggests a wide-spread desire to control operative access to various electrically powered appliances and apparatus. The reasons given for wanting to control such operative access are numerous. Among them are: to protect children and other individuals who do not possess sufficient knowledge or understanding of the operation of certain types of electrically powered equipment to operate same safely; to protect delicate electronic equipment from damage by untrained operators; to prevent economic waste of electricity and supplies (as for copy machines, fax machines, and laser printers), and to prevent unnecessary equipment wear; to control the viewing of television and video-tape programming by children; and to preserve the confidentiality of computer files.
Heretofore, however, locking devices such as those recited above were rendered ineffective (sometimes at the complete oblivion of the equipment owner) in the case of an appliance or apparatus equipped with a detachable power cord (such as are most personal computers and desk-top laser printers, for example). In such an installation, an unauthorized user could simply disengage the appliance cord from the appliance or apparatus, engage thereunto an alien, unencumbered power cord, engage the power plug of the alien appliance cord into an electrical wall outlet, and use the appliance or apparatus at will.
Many users of electrically powered apparatus that is equipped with detachable power cords would therefore find it desirable to have a power cord which they could readily engage and disengage from the apparatus, but which an unauthorized person could not disengage. Upon obtaining such a cord, the user could then avail himself of, and effectively use, any desired lockout or other device for controlling the flow of electrical current through the power cord to the user's electrically powered apparatus.
OBJECTS AND ADVANTAGES
Accordingly. several objects and advantages of my invention are: to provide the missing element (namely, the connector of this invention) required for the production of controllably detachable appliance power cords and cordsets to provide such cords and cordsets which may readily be used with existing appliance power connecting sockets without the need to alter or replace such sockets, to provide such cords and cordsets which require a minimum of skill and effort to use, and to provide such cords and cordsets which may be effectively used in conjunction with existing lockouts and devices designed to prevent the use of electrically powered appliances and apparatus by unauthorized persons.
In addition, I claim the following additional objects and advantages of my invention: to provide a missing element (namely, the connector of this invention) required for the production of controllably detachable appliance power cords and cordsets that are further distinguished by the imposition of a controlled (as with a key-operated or combination lock) switch in-line between the electrical-input end (which may be wired directly to an electrical power source or wired into an electrical circuit, or may be equipped with a power plug designed to be engaged in an electrical wall outlet, for instance) and the appliance-connecting end of such cords and cordsets, so that the resulting cords and cordsets provide complete protection against the unauthorized use of the electrical appliances and apparatus to which they are engaged, thus overcoming any need for additionally purchasing power lockouts or other devices designed to prevent the unauthorized use of electrically powered equipment.
Further objects and advantages of the invention will become apparent from a consideration of the accompanying drawings and the ensuing description.
DESCRIPTION OF DRAWINGS
FIG. 1 is a front perspective elevation view of a connector according to the invention.
FIG. 2 shows a side elevation view of such connector engaged and locked in a mating standard appliance power socket.
FIG. 3 shows a back view of such connector.
FIG. 4 is a top elevation view of such connector.
FIG. 5 is a top sectional view showing the connector of FIG. 2 as taken along the direction of angular line 5--5, with a second section being taken at the area of the lock assembly.
FIG. 6 is a back perspective view of the housing for such connector.
FIG. 7 is a fragmentary partial side sectional view of the connector of FIG. 5 showing the obstructing element assembly as taken along the direction of line 7--7.
FIG. 8 is a top view of the obstructing element of a connector according to the invention.
FIG. 9 shows a side view of the eccentric cam and unlocking rod of the connector of FIG. 3 as taken along the direction of line 9--9, shown in the locked position, with the unlocked cam position superimposed in phantom.
FIG. 10 is a front view of the eccentric cam attached to the lock assembly in such connector.
FIG. 11 is a fragmentary sectional side view of such connector shown engaged and locked in a mating standard appliance power socket.
FIG. 12 is a fragmentary sectional back view of the front portion of the connector and appliance power socket of FIG. 11 taken along the direction of line 12--12, showing the obstructing element of such connector.
FIG. 13 is a perspective bottom view of a sharp, chisel-pointed obstructing element and associated fulcrum of such connector.
FIG. 14 is a perspective bottom view of an alternate, serrated-tip embodiment of the obstructing element of such connector.
FIG. 15 is a perspective bottom view of an alternate, rubbery-tipped embodiment of the obstructing element of such connector.
FIG. 16 is a perspective relational elevation view of such connector and operatively associated equipment. The connector of the invention is shown engaged in the appliance power socket of a protected appliance. The power cord attached to the connector is shown engaged in a locking power-control device, and the power cord and plug of the latter are also shown.
FIG. 17 is a perspective back elevation view of such connector and mating standard appliance power socket.
FIG. 18 is a fragmentary cross-sectional front view of a portion of the housing of such connector, shown engaged in a mating standard appliance power socket, as taken along the direction of line 18--18 of FIG. 11.
FIG. 19 is an electrical schematic diagram of such connector and operatively associated power source, power cord, appliance power socket, and appliance internal electrical circuitry.
DRAWING REFERENCE NUMERALS
10 connector
12 housing of 10
14 face of 12
16 strain relief
18 power cord
20 first conductor
22 second conductor
24 grounding conductor
26 cavity in 12 for 38
28 lock assembly
30 key for 28
32 square hole in 38
34 flange on 48
36 rotating key plug
38 eccentric cam
40 machine screw
42 unlocked detent of 38
44 locked detent of 38
46 channel in 12 for 48
48 unlocking rod
50 elbow of 48
52 compression spring for 48 & 50
54 end of 48
56 chamber in 12
58 overhang of 56
60 electrical contact of 20
62 electrical contact of 22
63 grounding contact of 24
64 obstructing element
66 sharpened tip of 64
68 transverse cylindrical void in 64
70 fulcrum for 64, 88, or 106
72 cylindrical recess in 64
74 cylindrical recess in 58
76 compression spring for 64, 88, or 106
77 first terminal cavity in 12
78 second terminal cavity in 12
79 ground terminal cavity in 12
80 appliance power socket
82 recess in 80
83 first terminal of 80
84 second terminal of 80
85 ground terminal of 80
86 first terminal lug of 80
87 second terminal lug of 80
88 obstructing element
89 ground terminal lug of 80
90 rubbery mass affixed to tip of 88
92 transverse cylindrical void in 88
94 cylindrical recess in 88
98 lock washer
102 square shaft of 36
104 sharp, serrated tip of 106
106 obstructing element
108 protected appliance
110 electrical plug for 18
112 locking power-control device
114 power cord for 112
116 electrical plug for 114
118 cylindrical recess in 106
120 transverse cylindrical void in 106
122 electricity source
DESCRIPTION OF THE INVENTION
FIG. 1 shows a controllably detachable connector 10 for connecting an electrical appliance cord 18 to a mating appliance power socket 80 according to the best embodiment presently contemplated for carrying out the invention.
The location of connector 10 in relation to other operatively associated apparatus which is not part of the present invention is shown in FIG. 16. Connector 10 engages appliance power socket 80 of protected appliance 108. Power cord 18 is connected to connector 10 on one end, and terminates in a conventional electrical plug 110 on the opposing end. Electrical plug 110 is locked into a power socket in locking power-control device 112, which is connected to power cord 114, which in turn terminates in electrical plug 116.
Housing 12 is constructed of slightly resilient molded plastic of any variety that is commonly used for molded connectors found on cordsets. Power cord 18 confines insulated conductors 20 and 22, and insulated grounding conductor 24. Power cord 18 is permanently affixed to housing 12 by way of strain relief 16. As shown in FIG. 19, electricity source 122 is connected to conductors 20 and 22. Best seen in FIG. 5, conductor 20 is electrically connected to contact 60, which is disposed in cavity 77. Conductor 22 is electrically connected to contact 62, which is disposed in cavity 78. In similar fashion, grounding conductor 24 is electrically connected to grounding contact 63 disposed in cavity 79.
Key 30 is a controlled-access operating means for selectively locking connector 10 into and releasing same from appliance power socket 80. Key 30 engages lock assembly 28, best seen in FIG. 5. Lock assembly 28 is imbedded in the molded plastic of housing 12. Rotating key plug 36 is the portion of lock assembly 28 that can be rotated whenever key 30 is engaged. The inboard end of rotating key plug 36 terminates in a shaft 102 approximately 8 mm square by 3 mm long. Centered in the end thereof is a threaded mating hole for machine screw 40 Eccentric cam 38 is attached, by means of square hole 32, to shaft 102 with lock washer 98 and machine screw 40. Eccentric cam 38 and the inboard end of lock assembly 28 are disposed in cavity 26 of housing 12.
Best seen in FIG. 11, chamber 56 is a generally "L"-shaped void in connector 10 opposite cavity 79. It is essentially centered laterally within housing 12, and is about 6 mm wide. The bottom extent of the chamber is about 5 mm below the surface of housing 12. At the surface of housing 12, chamber 56 extends from about 7 mm to about 12 mm distant from face 14 At its longest extent, chamber 56 extends from about 4 mm to about 12 mm distant from face 14. At its end nearest face 14, chamber 56 is about 3 mm in vertical dimension, undercutting overhang 58 which is about 2 mm in thickness.
Obstructing element 64 is a metal blade about 5 mm wide by 11 mm long by 2 mm thick. It has an oblique cylindrical recess 72 about 1 mm deep aligned with spring 76 in the top surface of the end nearest face 14. Said element has a transverse cylindrical void 68 near its center. Said element terminates in a sharpened tip 66 which is flat on the top surface and bevelled sharply on the opposing surface, forming a cutting edge quite similar in scope to those found on common woodworking chisels. Obstructing element 64 is pivotally mounted in chamber 56 about fulcrum 70. Fulcrum 70 is a metal pin which extends through transverse cylindrical void 68, and whose ends are disposed in the plastic of housing 12. Spring 76 is a compression spring situated between cylindrical recess 72 of obstructing element 64, and cylindrical recess 74 of overhang 58.
Channel 46 is a rectangular passageway between cavity 26 and chamber 56. Unlocking rod 48 is a rectangular metal rod that extends from cavity 26 into chamber 56 via channel 46. Flange 34 is a flat metal plate encircling unlocking rod 48 and affixed thereto. Channel 46 is only slightly larger in breadth and depth than is unlocking rod 48. Elbow 50 begins as a generally right-angle bend in 48 about its vertical axis near the end that originates inside cavity 26, and terminates in a short leg that is generally rounded on the side that contacts eccentric cam 38. It is so-constructed that it intersects the path of cam 38 at an angle of approximately 90 degrees. End 54 of unlocking rod 48 is disposed in chamber 56 and contacts obstructing element 64 at a point nearer to face 14 than is transverse cylindrical Void 68. Spring 52 is a compression spring circumscribing unlocking rod 48. It is freely positioned between flange 34 on unlocking rod 48 and the front wall of cavity 26.
Appliance power socket 80 is a conventional appliance power connecting socket that is not part of the present invention, but is mechanically attached and electrically connected to an electrical appliance or device (especially a desk-top computer). First terminal 83 thereof is an elongated electrical connecting means disposed in recess 82 and firmly mounted in appliance power socket 80. It is electrically connected to first terminal lug 86, which is electrically connected to the internal power supply circuitry of the electrical appliance or device to be protected. Second terminal 84 thereof is an elongated electrical connecting means disposed in recess 82 and firmly mounted in appliance power socket 80. It is electrically connected to second terminal lug 87, which is electrically connected to the internal power supply circuitry of the electrical appliance or device to be protected. Ground terminal 85 thereof is an elongated electrical connecting means disposed in recess 82 and firmly mounted in appliance power socket 80. It is electrically connected to ground terminal lug 89, which is electrically connected to the grounding circuitry of the electrical appliance or device to be protected.
OPERATION
In order to connect an appliance power cord to an electrical appliance or device using the controllably detachable power cord connecting device of FIGS. 1-6, 16, and 17, the user should simply align terminal cavities 77, 78, and 79 of connector 10 with terminals 83, 84, and 85, respectively, of socket 80 mounted on the appliance or device to be protected, then push connector 10 into recess 82 of socket 80 as far as possible. Key plug 36 will normally be in its counterclockwise UNLOCKED position at this time, but even if it is in its clockwise LOCKED position, Key 30 will not be needed for this operation, since obstructing element 64 will be forced, upon encounter with the rigid structure of socket 80, to pivot about fulcrum 70 (compressing spring 76 in chamber 56) as far as is necessary to permit engagement of connector 10 into recess 82 of socket 80. As shown in FIG. 16, conventional electrical plug 110 on the end of the appliance power cord 18 opposite connector 10 of the invention should then be engaged in the electrical outlet of a locking power-control device (112) which, in turn, is connected to an electrical power source or supply circuit (122 of FIG. 19) by means of power cord 114 and electrical plug 116. If power cord 18 is constructed with an access-control means (such as a key-operated switch) in-line between connector 10 and conventional electrical plug 110 on the opposing cord end, then electrical plug 110 may be engaged directly in a conventional electrical wall outlet. These actions will result in:
(a) creation of a potential path for electrical current to flow from the electrical power source or supply circuit (122), through the access-control means (112), through first conductor 20 of power cord 18, through electrical contact 60, into first terminal 83 of appliance power socket 80, through first terminal lug 86, through the electrical load (shown in FIG. 19) of the appliance or device to be protected (108), and to return to the electrical power source or supply circuit via second terminal lug 87, second terminal 84, electrical contact 62, and second conductor 22;
(b) creation of a potential path for any anomalous electrical energy which may be present in the appliance or device to be protected, to flow from any grounding circuitry present in the appliance or device to ground terminal lug 89, through ground terminal 85, into grounding contact 63, disposed in ground terminal cavity 79 of housing 12, through grounding conductor 24, through the grounding prong of the conventional electrical plug 110 on the distant end of power cord 18, into the grounding contacts of the controlled-access power outlet or conventional wall-outlet socket, thence to ground via any existing grounding circuitry electrically connected to the ground contacts of the outlet;
Once connector 10 has been engaged in socket 80 as described above, key 30 should be engaged in lock assembly 28 and rotated clockwise until rotating key plug 36 is in its LOCKED position (unless rotating key plug 36 was already in the clockwise LOCKED position when connector 10 was engaged in socket which will result in the following:
(a) eccentric cam 38, being attached to shaft 102 by means of square hole 32 with lock washer 98 and machine screw 40, will rotate clockwise through an arc of approximately 90 degrees, at which time locked detent 44 is engaged by elbow 50 of unlocking rod 48;
(b) energy stored in compression spring 52 will press against flange 34 of 48, and thus will keep elbow 50 in contact with eccentric cam 38, and cause end 54 of unlocking rod 48 to move away from face 14 of housing 12;
(c) energy stored in compression spring 76 will cause obstructing element 64 to pivot about fulcrum 70, causing sharpened tip 66 to return to its locking position, extended beyond the body of housing 12 through the opening of chamber 56 in housing 12;
(d) connector 10 will be held engaged in appliance power socket 80 by means of sharpened tip 66 of obstructing element 64 digging into the plastic housing of appliance power socket 80, whereby disengagement of connector 10 is prevented; and
(e) when used in conjunction with the hereinabove-specified access-control means operatively associated with power cord 18, consummate control over the availability of electrical current to the appliance or device to be protected will by realized, since power cord 18 is mechanically and electrically connected to connector 10, which Will now be locked and engaged in appliance power socket 80 so as to circumvent surreptitious engagement of an alien, unencumbered appliance power cord therein.
Any person authorized to disengage connector 10 from appliance power socket 80 should be provided with an original or a copy of key 30 for lock assembly 28. When key 30 is engaged in lock assembly 28 and rotated counterclockwise to the UNLOCKED position, the following will result:
(a) eccentric cam 38, being attached to shaft 102 by means of square hole 32 with lock washer 98 and machine screw 40, will rotate counterclockwise through an arc of approximately 90 degrees, at which time unlocked detent 42 is engaged by elbow 50 of unlocking rod 48;
(b) energy stored in compression spring 52 will press against flange 34 of 48 and thus will keep elbow 50 in contact with eccentric cam 38;
(c) rotation of eccentric cam 38 will push unlocking rod 48 through channel 46 toward face 14 of housing 12;
(d) compression spring 52 will be squeezed between flange 34 and the front wall of cavity 26 in housing 12;
(e) end 54 of unlocking rod 48 will press against obstructing element 64 at a point between transverse cylindrical void 68 and face 14, causing obstructing element 64 to pivot about fulcrum 70;
(f) compression spring 76 will be compressed;
(g) sharpened tip 66 of obstructing element 64 will be retracted away from the plastic housing of appliance power socket 80 and into chamber 56 of housing 12;
(h) connector 10 may be disengaged from appliance power socket 80.
SERRATED-TIP OBSTRUCTING ELEMENT CONNECTOR
FIG. 14 shows a serrated-tip obstructing element 106 for the connector according to another embodiment of the invention. When the present invention incorporates obstructing element 106 of FIG. 14, in place of obstructing element 64 of FIG. 13, use, operation, and effect of the connector of the invention are exactly the same as specified in the preceding paragraphs.
The serrated-tip obstructing element 106 is distinguished from the chisel-pointed, sharpened-blade obstructing element 64 of FIG. 13 only in that the former includes multiple sharpened teeth (104) at the obstructing end, whereas the latter includes sharpened, chisel-pointed tip 66 at the obstructing end. When unlocking rod 48 is in its locking position, compression spring 76, being disposed between cylindrical recess 74 in overhang 58, and oblique, cylindrical recess 118 in obstructing element 106, will cause obstructing element 106 to pivot about fulcrum 70, which extends through transverse cylindrical void 120 in obstructing element 106, whereby serrated tip 104 will be held in contact with the housing of appliance power socket 80. When force is exerted by an unauthorized user in an effort to disengage connector 10 from appliance power socket 80, the sharp teeth of serrated tip 104 will dig into the plastic housing of appliance power socket 80, preventing disengagement of the connector.
Users will find use of the serrated-tip obstructing element connector advantageous when an appliance power socket 80 constructed of relatively hard plastic is encountered, since the several sharp teeth (104) of obstructing element 106 will dig into hard plastic with greater ease than will the chisel-pointed tip of obstructing element 64.
RUBBERY-TIPPED OBSTRUCTING ELEMENT CONNECTOR
FIG. 15 shows a rubbery-tipped obstructing element 88 for the connector according to another embodiment of the invention. When the present invention incorporates obstructing element 88 of FIG. 14, in place of obstructing element 64 of FIG. 13, use, operation, and effect of the invention are exactly the same as specified in the preceding paragraphs.
The rubbery-tipped obstructing element 88 is distinguished from the chisel-pointed, sharpened-blade obstructing element 64 of FIG. 13 only in that the former includes a mass of resilient, friction-producing material (90) affixed to a blunt, obstructing end, whereas the latter includes sharpened tip 66 at the obstructing end. When unlocking rod 48 is in its locking position, compression spring 76, being disposed between cylindrical recess 74 in overhang 58, and oblique, cylindrical recess 94 in obstructing element 88, will cause obstructing element 88 to pivot about fulcrum 70, which extends through transverse cylindrical void 92 in obstructing element 88, whereby rubbery tip 90 will be held in contact with the rigid housing of appliance power socket 80. When force is exerted by an unauthorized user in an effort to disengage connector 10 from appliance power socket 80, rubbery tip 90 will be wedged tightly into the space between obstructing element 88 and appliance power socket 80, preventing disengagement of the connector.
Users will find use of the rubbery-tipped obstructing element connector advantageous since it will not mar the inner surface of recess 82 in appliance power socket 80.
Thus, the reader will see that the connector of the invention provides the only remaining element needed but currently unavailable for the production of controllably detachable power cords and cordsets that can, when operatively associated with an effective, controlled-access means for selectively enabling and preventing the flow of electrical current through such power cords or cordsets, provide complete control over the availability of electrical power to electrical appliances and equipment that use detachable power cords or cordsets, yet requires no modification to existing electrical appliances, devices, or apparatus, and requires no tools or special skills for attaching to same electrical power cords or cordsets equipped with the connector of the invention.
While the above description contains many specificities, these should not be construed as limitations on the scope of the invention, but rather as exemplifications of preferred embodiments thereof. Those skilled in the art will envision many other possible variations that are within its scope. For example, skilled artisans will readily be able to change the dimensions and shapes of many of the components recited. They can mount the elements, described and illustrated as being located within chamber 56, within a rigid framework (as of metal or plastic, for instance), then insert the framework assembly into a generally rectangular chamber located at the approximate position of chamber 56 in the drawings. They can replace machine screw 40 with: a rivet; a nut and mating threads; or a welded joint., or they can produce rotating key plug 36 and eccentric cam 38 as a single piece of material. They can change the direction and angle of rotation required for key 30 to lock and unlock connector 10 by simply changing the shape of eccentric cam 38. They can replace the key lock with a combination lock and a tab, knob, or the like. They can replace compression spring 76 with mechanical linkage to hold the tip of the obstructing element (64, 88, or 106) in contact with socket 80. Accordingly, the reader is requested to determine the scope of the invention by the appended claims and their legal equivalents, and not by the examples which have been given. | An electrical connector (10) for a detachable power cord (18) that can be selectively locked in place when engaged in a standard appliance power socket (80) of an electrically powered applicance or device that utilizes a detachable power cord, such as a personal computer or a desk-top laser printer, for instance. A securing means (64, 88, 106) is provided to prevent removal of the connector from the appliance power socket, which in turn prevents circumvention of any access-control means that may be operatively associated with the power cord. A controlled-access operating means (30) is provided whereby an authorized user can lock the connector into or unlock the connector from the appliance power socket. | 8 |
BACKGROUND OF THE INVENTION
[0001] This invention relates generally to refrigerators, and more particularly, to ice dispenser assemblies for a refrigerator and methods of assembling the same.
[0002] Typically, automatic icemakers for household refrigerators produce crescent-shaped ice cubes. An example of an existing ice maker is shown in published patent Application US 2006,0016209. dated Jul. 26, 2006. A tray including a plurality of crescent-shaped compartments separated by slotted weirs is provided. Near the top of each compartment, slots in the weirs that separate each compartment from its adjacent compartment(s) allow water to flow between compartments as they are filled with water. Often, a water inlet is in fluid flow communication with a single compartment so that water fills the compartment past the bottom of the slot(s) or weir and into the adjacent compartment. As each compartment is filled, water runs through the slot in the weir into adjacent compartments so that each compartment is filled. Once all of the compartments are filled, the water stands in the compartments until it freezes to form ice cubes.
[0003] Once frozen, the ice cubes are removed from each compartment, typically by turning an ejector rake or arm. The rake member is typically mounted above the tray to rotate about the longitudinal axis of the tray. Typically, a separate finger or tab for each compartment extends radially from the ejector rake. The tab has a length sufficient to permit the free end to extend into a compartment when the ejector rake is rotated to urge the ice cube therein out of the compartment. To facilitate removal of the ice cubes, a heater often runs for a period to cause the ice in the ice tray to slightly melt on surface of contact of the ice tray. This melted ice (water) film between the ice cubes and the ice tray permits the ice cubes to slide more freely from the tray under the inducement of the ejector rake. This water film can reduce the torque exerted on the ejector rake.
[0004] A problem with existing ice makers is they harvest a slab of several webbed or fused cubes into an ice bin from the ice mold body (tray). The rotating ejector rake of the ice maker sweeps the ice from mold body. However, ice cubes are not broken apart from each other; rather, the ice cubes are swept out in one webbed slab that results from the water that remains in the weir slots and freezes with the ice cubes. Thus, the ice cubes are harvested from the tray as one large group or webbed slab, and often rely on being separated by a combination of the impact of their fall into the ice bin (or storage compartment) and by the motion of the ice auger. Often, the ice cubes are not fully separated by their fall into the ice bin or by the motion of the ice auger. This results in occasional groups of two or three cubes being dispensed to the consumer through the ice dispenser of a refrigerator or ice making machine. This often makes it difficult for consumers to dispense ice from the ice dispenser of a refrigerator, and the fused cubes are undesirable to consumers. This also makes it difficult to retrieve a single ice cube from the ice bin. Thus, it is desirable to provide an ice harvester that harvests ice cubes individually to make it easier for consumers to dispense ice from the ice dispenser of a refrigerator.
[0005] The Underwriter Laboratory may be requiring a hand/forearm probe test, which may result in the refrigerator including requiring a narrower ice chute. Thus, it is desirable to provide an ice dispensing system that results in a narrower ice chute for a single ice cube instead of groups of webbed cubes.
BRIEF DESCRIPTION OF THE INVENTION
[0006] The present invention relates to an ice cube maker. More particularly, it relates to an ice cube harvesting mechanism that dispenses single ice cubes instead of a slab of fused or webbed cubes. The ice bridge that connects ice cubes into a slab, which results from the freezing of the water channel that allows for even water distribution to the ice cube mold body to create equal-sized cubes during mold filling, is forced into the cube divider walls (weirs) of the mold body while the ice is being harvested; thus breaking the ice cubes apart. Thus, the cube divider walls (weirs) are designed to assist the breaking of the ice bridge between each cube.
[0007] An icemaker assembly includes an ice tray, an ice ejector member and a motor having an output shaft coupled to the ice ejector. The ice tray has at least two ice forming compartments that define a space. Rotation of the output shaft of the motor causes the ejector member to advance into the space whereby ice located in the space is urged in an ejection path of movement out of the at least two ice forming compartments.
[0008] An appliance is provided including a freezer compartment, an ice bin positioned within the freezer compartment and configured to store ice cubes therein.
[0009] An ice harvester has an ice cube tray having at least two compartments for holding ice cubes; a rotating member used to remove ice cubes from the ice cube tray; at least two arms extending radially from the rotary member for removing ice cubes from the ice cube tray; a motor coupled to the rotary member for powering rotation of the member; and a divider wall (weir) formed in the ice cube tray extending vertically between said arms having an edge, wherein the arms are rotated toward the edge to remove ice cubes from the tray, and wherein the edge breaks a web formed between adjacent ice cubes in the tray during rotation of the arms.
[0010] An ice harvester has an ice cube tray for holding a plurality of ice trays, the tray has a plurality of compartments formed by divider walls (weirs) extending from a bottom wall; a sweeping member extending along a longitudinal axis of the ice cube tray, the member has a plurality of bars extending from the member which remove ice cubes from the tray when the sweeping member is rotated about the longitudinal axis; wherein the bars are offset from the other along a circumference of the sweeping member.
[0011] An ice harvester has a tray for holding a set of ice cubes, the tray has a plurality of compartments formed by divider walls; an arm which rotates to sweep ice cubes from the ice tray; a plurality of bars extending from the arm to sweep the ice cubes from the tray: wherein each of the bars comprises a first portion and a second portion, wherein the second portion has a ramped surface to break apart the ice cubes.
[0012] A method for harvesting ice, includes providing a tray for forming and holding ice cubes, wherein the tray has a plurality of divider walls, each having a vertical edge; providing motorized arm (ejector rake) having a plurality of bars (ejector rake fingers) extending therefrom, wherein rotating the arm so that the bars contact the ice cubes in the tray; and pushing the ice cubes with the bars against the edges of the divider walls to break apart a web formed between the ice cubes so that single ice cubes are disposed from the tray.
[0013] One aspect of the invention is to allow for single, non-bridged cubes to be dispensed instead of a slab of webbed cubes.
[0014] Another aspect is to reduce the required ice chute dimension since only single cubes will be dispensed at a time.
[0015] Another aspect of the invention is the benefit to the user of dispensing single ice cubes.
[0016] Another aspect of the invention is it reduces required rotating ejector rake arm motor torque to dispense cubes. A rotating ejector rake of the icemaker that sweeps the ice from the mold body is modified to a staggered design in which each individual rake finger (bar) is offset at a certain angle relative to other rake fingers. This enables each ice cube to be contacted by its corresponding rake finger at different times.
[0017] A rotary ejector rake of the ice maker sweeps the ice from the mold body and allows the cubes to be broken apart at different times, and the cube divider walls facilitate the breaking of the ice bridge between ice cubes, thereby reducing required motor torque.
[0018] Additional features and benefits of the present invention will become apparent to those skilled in the art upon consideration of the following detailed description of preferred embodiments exemplifying the best mode of carrying out the invention as presently perceived.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] FIG. 1 illustrates a side-by-side refrigerator;
[0020] FIG. 2 illustrates an existing ice dispensing mechanism;
[0021] FIG. 3 illustrates a top view of a mold body (ice tray) of an ice dispensing mechanism;
[0022] FIG. 4 illustrates a side view of the mold body (ice tray) of FIG. 3 ;
[0023] FIG. 5 illustrates a side view of a modified mold body (ice tray) in accordance with an embodiment of the present invention;
[0024] FIG. 6 illustrates a bottom view of the mold body (ice tray) of FIG. 5 ;
[0025] FIG. 7 illustrates an ice dispenser with an ejector rake having a ramped edge in accordance with another embodiment of the invention;
[0026] FIG. 8 illustrates a side view of the mold body (ice tray) of FIG. 7 ; particularly the slot that allows for water to channel between compartments, and the weir around it;
[0027] FIG. 9 illustrates an ejector rake having three staggered sets of arms; each set being offset by a different angle (ranging from 0 to 180 degrees) relative to the other sets (one set of rake arms is at 0 degrees, a second set of rake arms offset from the first set by 7.5 degrees, and a third set of rake arms offset from the first set by 15 degrees) in accordance with another embodiment of the invention; and
[0028] FIG. 10 illustrates an ejector rake having arms staggered 15 degrees (angle can be anything between 0 and 180 degrees) apart in accordance with another aspect of the invention.
DETAILED DESCRIPTION OF THE INVENTION
[0029] Referring to FIG. 1 , an icemaker assembly 10 is incorporated in a freezer compartment 11 of a household side-by-side refrigerator/freezer 12 . However the invention applies to all types of refrigerators and freezer compartments. The illustrated refrigerator/freezer 12 includes a through-the-door ice and water dispenser. However, the invention can be used with ice cube trays in freezer compartments as well as other configurations. The icemaker assembly 10 includes an ice tray 14 , formed by a mold body 15 , an ice ejector rake 16 , an ice bin 18 , an ice dispenser 20 , a water inlet 22 , and a controller (not shown). The water inlet 22 is in fluid communication with ice tray 14 so that water is added to the ice tray. Water received in the ice tray freezes and is removed from the ice tray by the rake. Ice ejected from the ice tray is received in the ice bin 18 where it is stored. The ice bin includes a dispenser 20 from which ice is dispensed to the user. The dispenser is shown to be a through-the-door ice dispenser. The ice bin is configured to include a drive system of the dispenser for driving ice from the bottom of the ice bin to a dispenser opening 26 communicating with a chute 28 communicating with the ice outlet.
[0030] Referring now to FIGS. 2-4 , the ice dispenser includes a motor 30 having an output shaft, an ejector or rake arm 32 and a drive train coupling the output shaft of the motor to the ejector arm 32 . The rake arm includes a shaft 36 formed concentrically about a longitudinal axis 38 and a plurality of ejector or rake members 40 connected to and extending radially beyond the shaft 36 . The rake members can be rods, fingers, fins or tabs and are configured to extend from the shaft 36 into the ice tray when the shaft is rotated. The ejector members can be semi-circular in shape, rectangular, with ramped or sharp edges. Rotation of the output shaft of the motor is transferred through the drive train to induce rotation of the rake about its longitudinal axis 38 .
[0031] The motor 30 is controlled by the controller so that rotation of the ejector arm is stopped for a period of time to permit water to freeze in the ice tray. Once the water is frozen in the ice tray, the controller enables the motor to drive the ejector arm or rake in the direction of arrow 46 causing ice in the tray to be forced out of an ejection side 48 of the tray.
[0032] The ice tray is formed to include any number of semi-circular crescent or other shaped compartments 50 , an end inlet ramp 52 , a side inlet ramp 54 and ejector or rake arm mounting brackets 56 . The tray includes a plurality of divider walls (weirs) 58 to form the ice forming compartments 60 . The end inlet ramp is positioned below a water inlet to facilitate filling the compartments using a water channel through the slotted weirs method. The mounting brackets extend from the removal side of the ice tray to facilitate mounting the tray 20 to a mounting side or back wall of a freezer compartment.
[0033] Water from the water inlet flows down the inlet ramp (the rectangular portion above arm 32 ) into the rear ice-forming compartment. The water enters and fills the rear ice-forming compartment until the level reaches the level of the slot, channel of the weir and flows into the adjacent compartment. After water fills each compartment, it flows through the channel into an adjacent compartment. When the water in all of the compartments has reached a desired level, water flow stops.
[0034] Freezing of water in the channel (or slots in the weirs) results in the ice cubes all being one group of fused webbed ice cubes. The presence of the webbed ice increases the torque that the rake must exert to remove the ice cubes from the tray.
[0035] The compartments in the ice tray are substantially identical and are configured to include a space 64 in which semi-circular (or other shaped) ice cubes are formed. Each divider wall (weir) includes a top surface and two oppositely faced side surfaces. The compartments may be wide at the top and narrow near the bottom.
[0036] Water is released from the water inlet and flows down the end inlet ramp into the rear compartment. When sufficient water has entered the rear compartment to raise the level of the water in the compartment to the level of the slot in the weir/into the flow channel, water flows into an adjacent compartment until the adjacent compartment overflows into its corresponding adjacent compartment. This filling of the compartments through the channel continues until water has filled each compartment to a desired level.
[0037] Each cube is formed separately within its own compartment with an ice web extending between the cubes that results from water freezing in the channel/slot between weirs.
[0038] Once the ice cube has formed in each compartment, the controller can actuate a heater that heats the tray/mold body to slightly expand the tray and melt a small amount of ice cube adjacent the walls of each compartment.
[0039] Once the ice cubes are ready for removal, the controller actuates the motor to turn its output shaft that is coupled through the drive train to the ejector rake shaft 36 . The motor 30 drives the rake shaft to rotate about the rotation axis in the direction of the arrow 46 inducing a front portion 41 of each rake member to pass through a slot 43 in a cover 45 and into contact with the ice cube formed in its associated compartment. The front portion of each rake member contacts the top surface of its associated ice cube adjacent the narrow end of the cube downwardly along the arcuate bottom surface of the compartment.
[0040] The ejector rake arm proceeds along a path of movement a sufficient amount to completely remove the ice cubes from each compartment.
[0041] Referring to FIG. 3 , the mold body 15 is configured so that each cube in the mold body is filled by a water input, which eventually results in an ice bridge or web forming in the channel that allows for even water distribution to each cube. A heating mechanism, such as wires, in the mold body could be used to melt the ice bridge that forms between cubes.
[0042] Referring now to FIG. 4 , in the current ice harvesting mechanism, the mold body has water fill cutouts or slots 65 in the weirs between each compartment that allows water to enter and fill each of the compartments in the mold body/tray. The cutout/slot is shown in FIG. 4 to be on the right side of the mold body. The divider wall (weir) 58 , shown on the left side in FIG. 4 has a straight-edge 59 along the slot or cutout.
[0043] In the first embodiment of the present disclosure, a divider wall (weir) 70 is provided on an opposite or the right side of the mold body as seen in FIG. 5 . Wall 70 forms a straight or curved edge 72 that faces and forms part of the water fill cutout 74 . Essentially, the wall is the mirror image of the wall of FIG. 4 . As a series of rake arms 71 sweep the ice cubes from the mold body, the ice cubes contact the edge 72 of the vertical walls, which breaks the bridge or web or weir formed between the ice cubes as ice cubes are removed and harvested from the mold body/tray. The edge 72 faces the ejector rake arms as they rotate clockwise toward the removal direction, as shown as the arrow 76 . That is, the rake arms 71 rotate clockwise and contact and push the ice cubes toward the divider walls 70 . That is, the ice cube webs are broken apart by the sharp edge 72 of the divider wall (weir) 70 . The rake arm 71 , rotating toward the divider walls, brings the ice web into contact with wall 70 . FIG. 4 shows the opposite configuration where the divider walls do not break the web, since the rake arm rotates away from the divider wall (weir) 58 ; thus the web is not broken by the edge of the weir. FIG. 6 shows the underside of the ice cube mold body/tray with a curved bottom wall 61 of each compartment 60 having a wall (weir) 70 formed on one side of each compartment within the mold body.
[0044] In a second embodiment, referring to FIG. 7 , the weir divider wall has an edge 84 that aids in splitting the ice web as the ejector rake sweeps out the ice. The wall thickness of longitudinal portion 85 of the rake is maintained, and the angled portion 84 is about 1.5 to 2 times wider than longitudinal straight portion 85 ; as are the portions of the weirs (one such bottom portion of the weir is shown between 88 and 89 ) on the bottom of FIG. 7 . A sharp-edged tip 86 is added to the ramped portion 84 of weir to break apart the cubes as the ejector rake sweeps into the ice in the mold body the direction of arrows 83 and 87 .
[0045] Referring now to a side view of the mold body to show the slot/channel in the weir that allows water to flow from each compartment to the next in FIG. 8 , changing the shape of the weir wall from a flat edge to add a slight ramp 89 will decrease slot/channel width and thus decrease the size and width of the webs, thus facilitating breaking of the web and splitting of the ice cubes. This results in a reduction in the force required to break apart the ice. At the bottom, the weir also has a slightly raised portion 90 that still permits water distribution to all of the ice cubes. Like the ramp, this decreases size and width of webs, reducing required motor torque to break the webbing and separate the ice cubes. Referring to FIG. 8 , the ramp portion 89 replaces an existing straight edged (i.e., 90 degree) wall 91 (shown in phantom). Thus, the wall's configuration is modified to facilitate ice breaking by reducing the webbed/fused area by raising a bottom rib area of the weir and minimizing the area for even water distribution to the entire tray; thereby reducing the required breaking force.
[0046] Referring now to FIG. 9 , the ice harvester mechanism has an ejector rake 100 that is modified to break apart the cubes in separate batches. This results in a reduction of motor torque, and prevents the motor from stalling or shutting off to allow the ice to melt. Referring to FIG. 9 , the rakes are split into three sets or groups 102 , 104 , 106 . A first set 102 of rake arms 108 , 110 are configured at about 0 degrees with respect to a reference axis 112 . The second set 104 of rake arms 114 , 116 are offset by about 7.5 degrees (or other such angle) with respect to the first set. The third set 106 of rake arms 118 , 120 , 122 are offset by about 7.5 degrees (or another such angle) with respect to the second set (and 15 degrees with respect to the first set). Any other variation of angles or offsets are contemplated by the invention. Thus, the rake arms are staggered to break apart the cubes in batches. The rake members/bars at staggered angles will contact the top of the ice cubes at different times as the rotating ejector rake arm sweeps around, thus forcing the web in between cubes into the edge 86 of the slot in the weirs and subsequently separating the ice cubes at different times. That is, the first set contacts the outer two cubes before the second set contacts the next inner two cubes, and then the third set contacts the next inner three cubes. Each set of rake arms makes two web breaks to separate the cubes. This configuration can also be used with the mold body designed to split apart the cubes as seen in FIGS. 5 and 6 .
[0047] In still another embodiment, referring to FIG. 10 , two sets 130 , 132 of rake arms are offset by about 15 degrees (or any such angle) with respect to each other. That is, first set of rake arms 134 , 136 are positioned at about 0 degrees with respect to a reference axis 137 , and the second set of arms 138 - 146 are offset by about 15 degrees with respect to the reference axis. Any other variation of angles or offsets are contemplated by the invention. Thus, the rake arms are staggered to break apart the ice cubes in batches. That is, arms 134 , 136 break two cubes apart, then arms 138 - 146 break apart the remaining five cubes. The first set of two rake arms 134 , 136 makes three breaks in the cubes, and a second set of five rake arms 138 , 140 , 142 , 144 , 146 makes three breaks in the cubes as well. This configuration can also be used with the mold body of FIGS. 5 and 6 .
[0048] The invention has been described with reference to the preferred embodiments. Obviously, modifications and alterations will occur to others upon reading and understanding the preceding detailed description. It is intended that the invention be construed as including all such modifications and alterations. | An ice harvester has an ice cube tray having at least two compartments for holding ice cubes; a rotating member used to remove ice cubes from the ice cube tray; at least two arms extending from the rotary member for removing ice cubes from the ice cube tray; a motor coupled to the rotary member for powering rotation of the member; and a divider wall formed in the ice cube tray extending vertically between the arms having an edge, wherein the arms are rotated toward the edge to remove ice cubes from said tray, and wherein the edge breaks a web formed between adjacent ice cubes in the tray during rotation of the arms. The arms can be offset from each other along a circumference of the sweeping member. The edge of the divider wall can have ramped portions to facilitate the breaking apart of the cubes to reduce required motor torque. | 5 |
BACKGROUND OF THE INVENTION
The invention relates to a fuel injection pump. With such lifting slide-valve pumps, the volume control or the beginning of injection control is effected by the control of ports via which the pump working space can be connected to the suction space of the pump, namely by the assignment of control edges lying on the pump piston to the control edges lying in the control slide valve. For this reason, the rotational position of the control slide valve with respect to the cylinder liner must be fixed, with the result that, on the one hand, the control slide valve maintains a certain fixed rotational position in relation to the twistable pump piston and that, on the other hand, during basic adjustment, which is effected by slight twisting of the cylinder liner, which is subsequently clamped, the control slide valve is turned with it.
According to the object of such a control slide valve, the latter executes very many lifting cycles, with the result that a high wear load occurs at the guide surfaces of the anti-twist device. Added to this is the fact that, owing to the fuel control performed by twisting of the pump piston, the control slide valve must be guided very exactly in twisting direction, so that a twisting backlash between control slide valve and cylinder sleeve has a great effect on the metering and injection timing accuracy of the fuel, it being possible for even a small backlash to lead to considerable deviations of the actual control from the setpoint control.
In the case of a known fuel injection pump of the generic type (EP-A-0 181 402), a pin is arranged on the wall of the clearance of the cylinder liner, which pin engages in a longitudinal guide groove of the control slide valve, with the result that, upon the axial displacement of the control slide valve, the latter is secured against twisting by pin and guide groove. Disregarding the fact that the distance between pin and piston axis is relatively small, whereby the lever distance preventing the twisting is also relatively short, the pin has only line contact or, with slight inclined position, point contact toward the groove wall, which leads to a relatively rapid wear, with the consequence of the disadvantageous twisting backlash and corresponding deterioration in the control accuracy of the fuel. A further disadvantage consists in that such a pin can be fixed relatively poorly in the wall of the clearance, whereby during a loosening of this pin considerable damages directly on the pump and indirectly on the engine were possible.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide an improved fuel injection pump.
The fuel injection pump according to the invention has, in comparison, the advantage that the distance of the twisting guide point from the pump piston axis is increased, so that wear effects and thus backlash at the guide points have a lesser effect on the pump with respect to the associated twisting error of the control slide valve. The greater is the distance of the twisting guide from the piston axis, the smaller is the control error with a certain twisting backlash. With twice as long "lever guidance", the control error is only half as large with the same twisting backlash. A further advantage consists in that the anti-twist device according to the invention can be produced very inexpensively and is extremely sturdy and can be performed in terms of the precision working of this fit between lug and guide groove with simple customary working methods. A working loose of the lug from the control slide valve is not possible, with the result that no consequential damages in this respect can arise either. A further advantage consists in that the control slide valve is not additionally weakened by a groove or subjected to dimensional changes in heat treatment and during production on account of a groove, so that the "dynamic" slide valve durability is very good.
According to an advantageous development of the invention, the guide groove is designed as a slit-shaped perforation in the wall of the recess of the cylinder sleeve. Such a slit-like guide groove can be produced and worked in a simple way, the working in particular not taking place within the recess of the cylinder sleeve. A further advantage of this perforation in the wall of the cylinder sleeve consists in that it can be used for the fuel supply, with the result that, in the case of certain pump types with which these cylinder sleeves are arranged between a supply line and the suction space, additional connecting bores can be saved.
According to a further development of the invention, the lug has a rectangular longitudinal cross-section, measured in an imaginary plane which runs parallel to a tangential plane of the control slide valve and perpendicular to the longitudinal plane of symmetry of the lug, with the result that there are guide surfaces elongated in the adjustment direction of the lug toward the lateral limiting surfaces of the guide groove. According to one development of the invention, these guide surfaces are designed flat and parallel to the limiting surfaces of the guide groove, with the result that an area guidance is produced, with low Hertzian stress and correspondingly low wear. According to another development of the invention, the guide surfaces are designed slightly crowned (slightly convex), with the result that under a load there is an area contact between the lateral limiting surfaces of the guide groove and the guide surfaces of the lug. Such arrangements allow for a high force transmission with relatively low Hertzian stress and thus low wear. According to the invention, this line contact or else a surface contact, in which this surface has an as great as possible distance from the control slide valve, can be achieved in that the lug has a taper toward the control slide valve. Such a taper can be achieved for example by a relief cut or undercut.
According to a further advantageous development of the invention, the lug is arranged on one side of the control slide valve with respect to its displacement direction and the guide groove is correspondingly on one side in the cylinder sleeve. The effect achieved by this is that, when the fuel injection pump is installed, the control slide valve is always fitted in the correct installation position. With incorrect installation of the control slide valve, as can happen, for example in the case of symmetrical arrangement in longitudinal direction of the lug on the control slide valve, this is usually not discovered until the fuel injection pump is to be started up and the fuel control does not work at all or works completely incorrectly. This leads to high reworking costs in fabrication, as also in the case of incorrect installation during servicing, which is prevented by the development according to the invention.
The novel features which are considered as characteristic for the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 shows a longitudinal section, through the parts, of an injection pump, namely through a pump element including control slide valve of the first embodiment along line I--I in FIG. 2;
FIG. 2 shows a section along line II--II in FIG. 1.;
FIG. 3 shows a section corresponding to FIG. 1 through the second embodiment; and
FIG. 4 shows a partial section along line IV--IV in FIG. 3.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
In the embodiment shown in FIGS. 1 and 2, in each case only the pump element consisting of a pump piston 1 and a cylinder sleeve 2 as well as a control slide valve 3 is shown. As is known, this component is fitted in a fuel injection pump housing, in which the pump piston 1 can be set in a to and fro movement via a camshaft and against the force of a spring. At the lower end of the pump piston 1 is provided a flattened portion 4, on which a control rod (non-shown) for the twisting of this pump piston acts. A member for fuel control, likewise not shown, is an adjusting shaft, which engages by a pin in a transverse groove 5 of the control slide valve 3 and displaces the latter axially on the pump piston 1. In this embodiment, the cylinder sleeve 2 consists of two parts, which are fitted one in the other at 6 and are connected to each other for example by hard soldering or press-and-shrink fitting. Above the pump piston 1, there is in this cylinder sleeve 2 a pump working space 7, from which the fuel is conveyed via valves and lines (not shown) to the internal combustion engine. Furthermore, a central blind bore 8 is provided in the pump piston 1, which blind bore is crossed by a transverse bore 9 and a transverse bore 10. The transverse bore 10 is connected to oblique grooves 11 on the surface of the piston 1. In addition, radial bores 12 are provided in the annular slide valve 3.
The pump working space 7 is filled with fuel during the suction stroke and in the lower dead-center position shown, via the transverse bores 9, 10 and the axial bore 8, from a pump suction space 13, which surrounds in particular the control slide valve 3. In the compression stroke, fuel then flows back into the suction space 13, via the longitudinal bore 8, the transverse bore 9, the transverse bore 10 and the control grooves 11, until the transverse bore 9 enters the cylinder sleeve 2 or until these control grooves 11 enter the control slide valve 3. Only then does the actual injection to the internal combustion engine begin, which is thus dependent on the lift position of the control slide valve 3. This injection is interrupted when the oblique control edges 11 are activated by the radial bores 12 of the control slide valve 3 during the delivery stroke. Thereafter, the fuel flows out of the pump working space 7 via the axial bore 8, the transverse bore 10, the oblique grooves 11 and the radial bores 12, back into the suction space 13. Depending on the rotational position of the pump piston 1, i.e. depending on the relative position of the oblique grooves 11 with respect to the radial bores 12, this partial delivery stroke effective for injection is different.
The control slide valve 3 has on its rear surface facing away from the transverse groove 5 a lug 14, which is guided in a slit-shaped groove or perforation 15 of the cylinder sleeve 2. The lug 14 is arranged approximately in the center with respect to the longitudinal extension of the control slide valve 3. The side surfaces of the lug 14 and the guide surfaces of the perforation 15 facing said side surfaces of the lug run in parallel.
In the second embodiment shown in FIGS. 3 and 4, the corresponding reference numbers have been increased by 100 and to this extent reference is made to the parts already described in the first embodiment. In addition to what was already shown in the first embodiment, in this embodiment a part of the pump housing 17 is shown, in which a supply pipe 18 for the fuel is installed, from which fuel can flow via a radial bore 19 and a recess 21 in the pump housing 17 and via the slit-shaped perforation 115 into the recess 113 of the cylinder sleeve 102, in which the control slide valve 103 is arranged axially movably. In this embodiment as well, the control slide valve 103 has a lug 114, which is guided in the slit-shaped perforation or groove 115. In addition, in the pump housing 17 is provided a longitudinal bore 22 of greater cross-section, which intersects the recess 113, with the result that an open connection is produced. This longitudinal bore 22 forms the actual suction space of the pump together with the recesses 113 of the individual cylinder sleeve 102, usually arranged in series. This suction space is supplied with fuel at low pressure by a delivery pump (not shown).
In the longitudinal bore 22 is arranged the adjusting shaft 23, on which there are pins 24, which engage in the transverse groove 105 of the control slide valve 103. An adjustment of each pin 24 is possible via an opening 25 in the pump housing 17, this opening 25 being closable by a plug (not shown). Thus, the pin 24 and an opening 25 are assigned to each of the individual control slide valves 103 arranged in series, with the result that a whole series of such pins 24 are arranged on the adjusting shaft 23.
The essential difference between this second embodiment and the first embodiment consists in that the lug 114 is offset asymmetrically downwards with respect to the longitudinal extension of the control slide valve 103, with corresponding positional arrangement of the perforation 115. This prevents the control slide valve 103 from being fitted the wrong way round, for example with the lug 115 upwards.
As can be seen in FIG. 4, a further distinction from the first embodiment consists in that the lug 114 has an undercut at 26, with the result that the actual contact surface between lug 114 and the guide surfaces of the slitshaped perforation 115 does not begin until the edge 27 forming the end of the undercut 26.
It will be understood that each of the elements described above, or two or more together, may also find a useful application in other types of fuel injection pumps differing from the types described above.
While the invention has been illustrated and described as embodied in a fuel injection pump it is not intended to be limited to the details shown, since various modifications and structural changes may be made without departing in any way from the spirit of the present invention.
Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can, by applying current knowledge, readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention.
What is claimed as new and desired to be protected by Letters Patent is set forth in the appended claims. | Fuel injection pump for internal combustion engines with at least one pump element and a control slide valve, axially displaceable on the pump piston, and, for fuel control, additionally the twistable pump piston, the control slide valve being secured against self-twisting by a lug, which is guided in a slit-shaped groove of the cylinder sleeve of the pump element. | 5 |
[0001] This application claims priority on U.S. provisional application Ser. No. 60/727,013 filed Oct. 14, 2005.
[0002] This invention relates to the field of fiber processing and testing. More particularly, this invention relates to correcting to standardized laboratory conditions the measurements that are taken on fibers at nonstandard laboratory conditions.
FIELD
Background
[0003] Fiber testing, such as for length and strength, is typically performed in a temperature and humidity controlled environment. Internationally used standards such as the American Society for Testing and Materials (ASTM) Standard Number D-1776 prescribe standard laboratory conditions for testing textile materials such as fibers at 21° Celsius +/−1° and 65% relative humidity +/−2%.
[0004] One reason for controlling the temperature and humidity of the fibers during testing in this manner is that the moisture content of such fibers tends to affect characteristics of the fibers, such as length and strength. For example, fibers with higher moisture content tend to exhibit less crimping, and thus fiber length tests tend to report these fibers as having a greater length. Further, possibly due to increased hydrogen bonding between adjacent water molecules in the space between cellulose sheaths and other effects, strength tests on fibers with higher moisture content tend to report such fibers as having a greater strength.
[0005] Thus, all fiber testing is most preferably performed at any standard laboratory conditions. In this manner, tests that are performed in different geographical locations and at different times, and which might otherwise have different temperature and humidity conditions in the laboratory, can be reliably compared one to another. When tested under the standardized ASTM conditions given above, it has been assumed that all cotton fibers will equilibrate to a given moisture content of 8.0%. (Re-arranged Order)
[0006] However, most fiber testing is not performed under any standardized laboratory conditions. In such nonstandard laboratory conditions, the moisture in the cotton fiber is in equilibrium with the moisture in the air. As a result, the measurements not only may be at different levels in different laboratories but also vary throughout the day as the conditions in an individual laboratory change.
[0007] Previous attempts at moisture corrections to the length and strength data have focused on the use of either external moisture measurements or measurements of temperature and relative humidity. The correction is then performed using a correlation between either the directly measured or estimated moisture content and measurements made at standard laboratory conditions. In this manner, measurements taken in nonstandard laboratory conditions can be compared to measurements taken in standard ASTM laboratory conditions at an assumed moisture content of 8.0%.
[0008] Unfortunately, there does not appear to be a good correlation between such corrected nonstandard laboratory condition measurements and any standard laboratory condition measurements. What is needed, therefore, is a method that provides a better correlation between the results obtained for fibers tested at standard laboratory conditions, and the corrected results obtained for fibers tested at nonstandard laboratory conditions.
SUMMARY
[0009] The above and other needs are met by a method for standardizing a measurement of a fiber sample, including the steps of measuring a moisture content of the fiber sample actually being measured during the time of measurement, measuring the fiber sample, and correcting the measurement to a standardized moisture measurement that adjusts for a difference between the measurement at the measured moisture content of the fiber sample and a standardized moisture measurement. An appropriate standardized moisture content is about 7.5% moisture content for ASTM laboratory conditions. If one's selected standard laboratory conditions are different than ASTM conditions, then one can select a different standardized moisture content. Preferably, the measurement includes at least one of fiber length and fiber strength.
[0010] Different cotton samples equilibrate to different moisture contents, depending at least in part upon a number of different factors, as described in more detail hereafter. Measurements at different combinations of temperature and relative humidity on a sample set of approximately forty cottons were used to develop the algorithm which corrects for the difference is moisture content between the measured moisture content and the standardized moisture content. These cottons were chosen to span the range of fiber properties from growth areas throughout the world. It has been determined that the analysis to determine the correction must include the actual equilibrium moisture at standard conditions for each sample in this sample set used to determine the correction rather than the assumed 8.0% moisture content. Further, it has been determined that correcting the measurements that are taken at different moisture contents to standardized measurements based on about 7.5% moisture content provides a more accurate overall estimate of the standardized measurements compared to correcting the measurements to values that are based on standard ASTM laboratory conditions at the assumed 8.0% moisture content.
[0011] The correction is performed using a measurement of the moisture content of the sample during the time of measurement. In the preferred embodiment, the moisture of the small specimen fiber sample being tested is measured during the time of the measurement. Since the moisture content of the bulk fiber sample, of which small specimen fiber samples are taken, exhibits a distribution affecting the individual measurements, this will reduce the variations in the individual measurements of the different small specimen fiber samples. It has been found that the sample preparation process may significantly change the moisture content of the sample being measured. For this reason, it is preferred that the moisture measurement be of the moisture content of the sample during the time of measurement. This is preferably accomplished by measuring the moisture content of the small sample being measured or alternatively by proper design of the measuring instrument. The measurements are then adjusted using a correlation between the directly measured moisture content and the standard moisture content as described above in regard to testing in standard laboratory conditions. In this manner, measurements taken in nonstandard laboratory conditions can be compared to measurements taken in standard laboratory conditions.
[0012] The step of correcting the measurement is alternately accomplished by at least one of applying an algorithm that correlates measurements at different moisture contents, manipulating the measurement in a mathematical equation that correlates measurements at different moisture contents, and using a chart that correlates measurements at different moisture contents.
[0013] In some embodiments, the step of correcting the measurement includes correcting the measurement to a moisture content value other than about 7.5%, where the moisture content value is determined based at least in part on fiber characteristics such as at least one of geographical growth location including country and region, growth conditions including rainfall, sunlight, time of year, growth year, harvesting and ginning methods, fiber color, fiber type, and fiber trash content.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] Further advantages of the invention are apparent by reference to the detailed description when considered in conjunction with the figures, which are not to scale so as to more clearly show the details, wherein like reference numbers indicate like elements throughout the several views, and wherein:
[0015] FIG. 1 depicts a graphical plotting of Maximum Moisture Content in Air versus Temperature.
[0016] FIG. 2 depicts a graphical plotting of Measured Sample Moisture Content for Sample M- 3 compared to relative moisture calculated from temperature and relative humidity.
[0017] FIG. 3 depicts a graphical plotting of Measured Sample Moisture Content for Sample M- 6 compared to relative moisture calculated from temperature and relative humidity.
[0018] FIG. 4 depicts a graphical plotting of Measured fiber length as a function of sample moisture content for several different cotton samples.
[0019] FIG. 5 depicts a graphical plotting of Measured fiber strength as a function of sample moisture content for several different cotton samples.
[0020] FIG. 6 depicts a graphical plotting of Measured fiber equilibrium moisture contents at 55% relative humidity and 71.3° Fahrenheit.
[0021] FIG. 7 depicts a graphical plotting of Measured fiber equilibrium moisture contents at 60% relative humidity and 71.8° Fahrenheit.
[0022] FIG. 8 depicts a graphical plotting of Measured fiber equilibrium moisture contents at 75% relative humidity and 75.9° Fahrenheit.
DETAILED DESCRIPTION
[0023] Cotton samples gain or lose moisture in response to the moisture concentration in the ambient atmosphere. Relative humidity is defined as the percentage of moisture per liter of air compared to the maximum moisture per liter of air that will not produce condensation at that temperature. Relative humidity tends to be a relatively non-linear function within the range of interest as described herein. FIG. 1 depicts a graphical plotting of maximum moisture content in air versus temperature. As depicted, the relationship is not linear.
[0024] The actual moisture content in the air, such as measured in grams per liter, is determined by multiplying the relative humidity times the maximum value as determined by the temperature. Internationally used standards such as the American Society for Testing and Materials (ASTM) Standard Number D-1776 specify standard laboratory conditions at 21° Celsius +/−1° and 65% relative humidity +/−2%, in order to fix the amount of moisture content in the air during both conditioning and testing of the cotton fibers for characteristics such as length and strength. In order to allow the cotton sample time to acclimate to the laboratory conditions, the sample is required to remain in the laboratory for twenty-four hours before being tested.
[0025] In FIGS. 2 and 3 , the cotton sample moisture content of the two different samples as actually and directly measured is compared to the relative moisture content in the air at different laboratory conditions. The relative moisture content is the ratio of the moisture content in the air at a given temperature and relative humidity as compared to that at standard laboratory conditions. As can be seen, the correlation between the relative moisture content and the actual sample moisture content as directly measured is fairly good for both samples but differs slightly between samples.
[0026] As mentioned above, the sample moisture content is important in fiber measurement because the physical properties of the fiber change due to the absorbed moisture. Without being bound by theory, it is believed that when the moisture penetrates the fiber, weak hydrogen bonds are formed between adjacent fiber sheaths. This results in increased fiber strength. The natural fiber crimp is also reduced, resulting in increased measured fiber length.
[0027] FIG. 4 depicts a graphical plotting of measured fiber length as a function of sample moisture content in four different cotton samples. As can be seen, the measured length of the fiber sample tends to increase as the moisture content increases. FIG. 5 depicts a graphical plotting of measured fiber strength as a function of sample moisture content in four different cotton samples. Again, as can be seen, the measured strength of the fiber sample tends to increase as the moisture content increases.
[0028] Based on these concepts, prior art methods previously corrected all measurements to measurements made at standard ASTM laboratory conditions with an assumed moisture content of 8.0%. However, different cotton samples equilibrate at different moisture contents under the same laboratory conditions. The histograms depicted in FIGS. 6-8 show the distributions of equilibrium moisture contents for different cotton samples under different laboratory conditions. As can be seen in each histogram, there is a spread in equilibrium moisture contents for each set of laboratory conditions, indicating that some samples had a relatively lower moisture content at the laboratory conditions stated, and some samples had a relatively higher moisture content at the laboratory conditions stated. Additionally, the moisture measurements were not representative of the sample moisture at the time of measurement due to either varying laboratory conditions or changes in the moisture of the sample being measured due to sample preparation processes.
[0029] Using data such as that described above, regression curves can be constructed for each cotton sample and the equilibrium moisture content can be calculated for any standard laboratory conditions. When this is done, the change in fiber measurements can be related to differences between the measured moisture content and the actual equilibrium moisture content for that sample rather than the assumed 8.0% moisture content. The importance of this discrepancy arises when attempting to calculate a group behavior for all samples. Unless a proper group behavior is analyzed, the resulting algorithm will not be robust, resulting in poor correlations between the corrected measurements and the actual measurements measured at standard ASTM laboratory conditions.
[0030] However, measurements can be made to correlate to measurements at any standard laboratory conditions with a greater degree of precision if additional characteristics of the cotton fiber sample are accounted for. As mentioned above, it has been determined that cotton samples tend to equilibrate to different moisture contents, even though they are held at the same laboratory conditions in terms of temperature and relative humidity. This indicates that the moisture content of a cotton fiber sample is dependent upon more variables than just temperature and relative humidity. It has been determined that the moisture content of a cotton fiber sample is additionally based on at least one of a variety of other fiber characteristics, including geographical growth location including country and region, growth conditions including rainfall, sunlight, time of year, growth year, harvesting and ginning methods, fiber color, fiber type, and fiber trash content.
[0031] This information can be used to more accurately standardize and correct the measurements made on fiber samples. For example, a fiber sample having known characteristics as mentioned above can be acclimated at the standard laboratory temperature and relative humidity. Then the moisture content for the fiber sample can be directly measured during the fiber measurements cycle. By directly measured it is meant that the moisture content is measured by a method or device that does not rely on a correlation to the temperature and relative humidity present in the laboratory. For example, such a method would include a resistance measurement. This process avoids errors due to sample moisture content distributions and changes in sample moisture content due to sample preparation processes.
[0032] Once the actual moisture content for the fiber sample is known, measurements taken at nonstandard laboratory conditions are then corrected to values that correlate to the actual moisture content as directly measured, rather than to some assumed moisture content value. By constructing charts in this manner of actual moisture contents based upon the varying characteristics as described above, a more accurate measurement data correction can be constructed. According to the more accurate measurement data correction, more than just the moisture content of the fiber sample is used to correct the measurements. Instead, the other characteristics as mentioned above are additionally used to determine the moisture content value to which the measurements should be corrected. In this manner, measurements taken on samples at standard laboratory conditions will compare more accurately with corrected measurements taken on samples at nonstandard laboratory conditions.
[0033] The foregoing description of preferred embodiments for this invention has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form disclosed. Obvious modifications or variations are possible in light of the above teachings. The embodiments are chosen and described in an effort to provide the best illustrations of the principles of the invention and its practical application, and to thereby enable one of ordinary skill in the art to utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. All such modifications and variations are within the scope of the invention as determined by the appended claims when interpreted in accordance with the breadth to which they are fairly, legally, and equitably entitled. | A method for standardizing a reading taken on a fiber sample, including the steps of measuring a moisture content of the fiber sample, taking the reading on the fiber sample, and correcting the reading to a standardized reading that adjusts for a difference between the reading at the measured moisture content of the fiber sample and a standardized reading at about 7.5% moisture content. | 6 |
CROSS REFERENCE TO RELATED APPLICATIONS
The present application is a continuation of U.S. application Ser. No. 12/684,842, filed Jan. 8, 2010 (now U.S. Pat. No. 8,315,119), which claims priority of U.S. Provisional Application 61/155,801 filed Feb. 26, 2009, which are incorporated herein by reference in their entireties.
TECHNICAL FIELD
This present application relates generally to semiconductor devices, and more particularly to memory arrays, and even more particularly to the design and operation of static random access memory (SRAM) arrays and/or register files that use single ended sensing to sense the data in a bit cell.
BACKGROUND
Static random access memory (SRAM) is commonly used in integrated circuits. SRAM cells have the advantageous feature of holding data without a need for refreshing. SRAM cells may include different numbers of transistors, and are often accordingly referred to by the number of transistors, for example, six-transistor (6T) SRAM, eight-transistor (8T) SRAM, and the like. The transistors typically form a data latch for storing a data bit. Additional transistors may be added to control the access to the transistors. SRAM cells are typically arranged as an array having rows and columns. Typically, each row of the SRAM cells is connected to a word-line, which determines whether the current SRAM cell is selected or not. Each column of the SRAM cells is connected to a bit-line (or a pair of bit-lines), which is used for storing a data bit into a selected SRAM cell or reading a stored data bit from the selected SRAM cell.
A register file is an array of processor registers in a central processing unit (CPU). Integrated circuit-based register files are usually implemented by way of fast SRAMs with multiple ports. Such SRAMs are distinguished by having dedicated read and write ports, whereas ordinary multi-ported SRAMs will usually read and write through the same ports.
With the scale of integrated circuits decreasing, the operation voltages of integrated circuits are reduced and similarly the operation voltages of memory circuits. Accordingly, read and write margins of the SRAM cells, which are used to measure how reliable the data bits of the SRAM cells can be read from and written into, respectively, are reduced. Due to the existence of static noise, the reduced read and write margins may increase the possibility of errors in the respective read and write operations.
For single ended sensing of a memory cell, the precharged local bit-line either stays at the precharged level or it is discharged to ground level depending on the data that is stored in the bit-cell. When the local bit-line is kept floating during the case where the cell does not have the data value to discharge the local bit-line, the leakage from the pass gates (all cells in one column) discharges the local bit-line to zero during low frequency operation, thus making a false sensing. To avoid this false sensing issue, the local bit-line is kept at Vdd through a weak (small current) precharger device, i.e. a “keeper” circuit.
FIG. 1 illustrates a conventional sense amplifier circuit 100 that can be a portion of a SRAM array or register files, and includes a keeper circuit 102 . The size of components of the keeper 102 is very critical in order to assure that the bit-cell overpowers the keeper 102 for a normal read operation. The circuit 100 is connected to bit-lines, i.e. top bit-line 108 a and bottom bit-line 108 b . The precharger 110 charges the local bit-line 108 a and 108 b to high state according to the control signals 114 when there is no read operation. During manufacturing of the memory as disclosed in FIG. 1 , there are acceptable variations in performance parameters. Process corners refer to integrated circuits with lowest and/or highest desirable performance parameters. Skew corners refer to integrated circuits with both lowest and highest desirable performance parameters in their sub-circuits. At low voltages, and skew corners (e.g. slow array transistors in bit-line 108 a or 108 b and fast periphery transistors in a keeper 102 ), the bit-cell connected to the bit-line 108 a or 108 b will not be able to overpower this keeper 102 . Therefore, there is a limitation on the lowest desirable power supply voltage, i.e. Vdd_min, for the circuit to operate without error.
One way to make this circuit 100 work properly under low voltage is to increase the resistance of the keeper 102 , such as increasing the channel length of the keeper transistor 104 or decreasing the width of the same. This will make the keeper 102 easier to be overcome by the bit-cell connected to the bit-line 108 a or 108 b . However, this method has its limits due to the area that the keeper transistor 104 occupies and also the current flow level necessary for the keeper 102 to provide the leakage current from the pass gates and thus make it operational.
Another way to make the circuit 100 operational under low voltage is to make the trip point voltage of the NAND gate 106 higher, where the trip point is the highest voltage where the sense amplifier output switches from a high level to a low level. For that purpose, for example, when the NAND gate 106 comprises NMOS and PMOS, the value of β of the NAND gate 106 can be increased, where β is the ratio of Wp/Wn, and Wp and Wn are the gate widths of PMOS transistor and NMOS transistor, respectively. This ratio β determines the trip point in CMOS circuits. However, this will make the circuit 100 susceptible to noise closer to the high state voltage because the trip point is higher. For example, when there is noise in the bit-line 108 a or 108 b close to a high state, the output voltage could be lowered by the noise below the trip point of the NAND gate 106 , which triggers an erroneous operation.
Therefore, methods to avoid false sensing the local bit-line under low voltage for SRAM and/or register files are desired.
SUMMARY
In one embodiment, a sense amplifier circuit includes a pair of bit lines, a sense amplifier output, a keeper circuit, and a noise threshold control circuit. The keeper circuit is coupled to the pair of bit lines and includes an NMOS transistor coupled between a power node and a corresponding one of the pair of bit lines. The keeper circuit is sized to supply sufficient current to compensate a leakage current of the corresponding bit line and configured to maintain a voltage level of the corresponding bit line. The noise threshold control circuit is connected to the sense amplifier output and the pair of bit lines. The noise threshold control circuit comprises a half-Schmitt trigger circuit or a Schmitt trigger circuit.
In another embodiment, a sense amplifier circuit includes a pair of bit lines, a sense amplifier output, a keeper circuit, a logic gate, and a noise threshold control circuit. The keeper circuit is coupled to the pair of bit lines and includes a first NMOS transistor coupled between a first power node and a corresponding one of the pair of bit lines. The keeper circuit is sized to supply sufficient current to compensate a leakage current of the corresponding bit line and configured to maintain a voltage level of the corresponding bit line. The logic gate has input nodes and an output node. The input nodes are coupled to the pair of bit lines, and the output node is coupled to the sense amplifier output. The noise threshold control circuit is connected to the sense amplifier output. The noise threshold control circuit is configured to have greater driving capability to pull a voltage level of the sense amplifier output toward that of a second power node than to pull the voltage level of the sense amplifier output toward that of the first power node.
In yet another embodiment, a sense amplifier circuit includes a first data line, a second data line, a sense amplifier output, a keeper circuit, and a noise resistant gate. The keeper circuit comprises a first transistor and a second transistor connected in series and coupled between a first power node and the first data line. A gate of the first transistor is coupled to the sense amplifier output. The noise resistant gate comprises a first input node coupled to the first data line, a second input node coupled to the second data line, and an output node coupled to the sense amplifier output. The noise resistant gate is configured to have greater driving capability to pull a voltage level of the sense amplifier output toward that of a second power node than to pull the voltage level of the sense amplifier output toward that of the first power node.
BRIEF DESCRIPTION OF THE DRAWINGS
For a more complete understanding of the present disclosure, and the advantages thereof, reference is now made to the following descriptions taken in conjunction with the accompanying drawings, in which:
FIG. 1 is a schematic diagram of a conventional sense amplifier circuit;
FIG. 2 is a schematic diagram of a sense amplifier circuit according to one embodiment of the present disclosure;
FIG. 3 is a schematic diagram of a half-Schmitt trigger circuit for used as an exemplary noise threshold control circuit 206 in FIG. 2 ;
FIG. 4 is a graph of the output of the bit-line read/sense amplifier/read showing a trip point or the voltage at which the sense amplifier receiver switches with the same bit-line slope for (1) a prior art circuit with β=3.3, (2) a prior art circuit with β=16.7, and (3) a proposed circuit according to one embodiment of the disclosure with β=3.3;
FIG. 5 is a graph of the output of the bit-line read/sense amplifier/read showing the bit-line slopes for (1) a prior art circuit with β=3.3, (2) a prior art circuit with β=16.7, and (3) a proposed circuit according to one embodiment of the disclosure with β=3.3, with different bit-line voltage lines for prior art circuit and the proposed circuit;
FIG. 6 is a schematic diagram of another embodiment of the sense amplifier circuit according to one aspect of the present disclosure;
FIG. 7A is a schematic diagram of yet another embodiment of the sense amplifier circuit according to the present disclosure;
FIG. 7B is a schematic diagram of an variation of the sense amplifier circuit according to the embodiment depicted in FIG. 7A ; and
FIG. 8 is a schematic diagram of yet another embodiment of the sense amplifier circuit according to the present disclosure.
DETAILED DESCRIPTION
The circuits of the presently preferred embodiments are discussed in detail below. It should be appreciated, however, that the present disclosure provides many applicable concepts that can be embodied in a wide variety of specific contexts. The specific embodiments discussed are merely illustrative, and do not limit the scope of the disclosure. A skilled person will appreciate alternative implementations.
FIG. 2 is a schematic diagram of a sense amplifier circuit 200 according to one embodiment of the present invention. The sense amplifier circuit 200 has a keeper circuit 202 . The circuit 200 is connected to bit-lines, i.e. top bit-line 208 a and bottom bit-line 208 b . The precharger 210 charges the local bit-line 208 a and 208 b to a high state according to the control signals 214 when there is no reading operation.
Further, the keeper circuit 202 has NMOS transistors 204 and a noise resistant NAND gate 206 . In this particular example, the gate node of the NMOS transistor 204 in the keeper circuit 202 is connected to the power supply node and its source node is connected to the bit line. The drain node of the NMOS transistor 204 is connected to the power supply node through a PMOS transistor. The NMOS 204 is only in sub-threshold until the bit-line read voltage reaches V dd −V T , where V T is the threshold voltage of the transistor, thus effectively making the keeper circuit 202 weaker, i.e. easier to be overcome by the bit-line as its voltage decreases. In one embodiment, the noise resistant NAND gate 206 (or a noise threshold control circuit) is a half-Schmitt trigger; in another embodiment, the noise resistant NAND gate 206 is a Schmitt trigger as depicted in FIG. 2 . However, in alternative embodiments, alternative circuits may be formed by rearranging the devices so that the β ratio is decreased or the trip point is lowered.
FIG. 3 is a schematic diagram of one example of the noise threshold control circuit 206 as indicated by NAND gate symbol in FIG. 2 , using a half-Schmitt trigger circuit.
By lowering the trip point of the sense amplifier out, it is possible to use a lower precharge voltage level on the bit-line and avoid false sensing of the bit-line read. The trip point is the highest voltage where the sense amplifier output switches from a high level to a low level. The response time of the bit-line to output is reduced because of the improved bit-line slope of the new circuit design. The response time of the sense amplifier output is faster due to the new scheme. Further, in at least some embodiments, the local bit-line is precharged to V dd −V T , instead of V dd .
The keeper circuit 204 using NMOS transistors as shown in FIG. 2 make the keeper circuit 202 effectively weaker, i.e. easier to overcome by the bit-line. However, this in turn can make the prior art circuit susceptible to noise when there are voltage fluctuations on the bit-line 108 a or 108 b . To avoid the noise susceptibility, a noise threshold control circuit 206 , e.g. a half-Schmitt trigger or a Schmitt trigger circuit is used in place of the prior art NAND gate 106 . This scheme makes it possible to perform the bit-line read operation without false sensing at lower power voltage by having a lower trip point.
FIG. 4 is a graph of the trip point or the voltage at which the sense amplifier receiver switches with the same bit-line slope for (1) a prior art circuit with β=3.3, (2) a prior art circuit with β=16.7, and (3) a proposed circuit with β=3.3. The bit-line read plot is based on the prior art circuit 100 shown in FIG. 1 . In FIG. 4 , the prior art circuit 100 with β=3.3 has the trip point at point (1). The prior art circuit 100 with β=16.7 has the trip point at point (2). The purpose of increased β is to make the keeper circuit 102 weaker so that the bit-line read can overcome the keeper circuit 102 at lower power supply voltage. As shown in FIG. 4 , the trip point (2) is higher than trip point (1). In one circuit simulation under the power supply voltage of 0.7V according to one of the embodiments, the difference is about 34 mV. However, by increasing the trip point, the sense amplifier output is susceptible to the bit line read voltage fluctuations caused by noise. This makes the prior art circuit difficult to operate at lower voltage. In comparison, the proposed circuit 200 with β=3.3 according to one of the embodiments has trip point at point (3). The trip point (3) is lower than (1) or (2). In the simulation under the power supply voltage of 0.7V, the difference between (3) and (1) is about 77 mV, and the difference between (3) and (2) is about 111 mV. This makes the proposed circuit easier to operate at lower voltage. Also, in another simulation with the power supply voltage of 0.6V, both sense amplifier circuits according to prior art do not work at all, i.e. the sense amplifier outputs do not switch when the bit-line voltage dropped, while the proposed circuit operates properly.
FIG. 5 is a graph of the output of the bit-line read/sense amplifier/read showing the bit-line slopes for (1) a prior art circuit with β=3.3, (2) a prior art circuit with β=16.7, and (3) a proposed circuit with β=3.3, with different the bit-line voltage lines for prior art circuit and the proposed circuit. FIG. 5 shows a separate bit-line read voltage plot for the circuit 200 according to one of the embodiments. The same bit-line read voltage based on the prior art circuit 100 shown in FIG. 1 is shown to facilitate understanding. As shown, the prior art circuit with β=16 has a shorter response time (the time where the trip point (2) is positioned) compared to the response time of point (1) of the prior art circuit 100 with β=3.3. However, the proposed circuit response time (the time where the trip point (3) is positioned) is even shorter than the prior art with β=16.7 (the time where the trip point (2) is positioned). In one simulation under the power supply voltage of 0.7V, the difference between (3) and (1) is about 0.9 ns, while the difference between (3) and (2) is about 0.2 ns.
FIG. 6 is a schematic diagram of another embodiment of the sense amplifier circuit 600 according to the present disclosure. In this embodiment, the NMOS 604 transistor in the keeper circuit 602 is configured as a diode by connecting its gate and drain node of the NMOS transistor 604 . The drain node of the NMOS transistor 604 is connected to the power supply node Vdd through a PMOS transistor 606 . The source node of the NMOS transistor 604 is connected to the bit line 208 a and/or 208 b.
FIG. 7A is a schematic diagram of yet another embodiment of the sense amplifier circuit 700 according to the present invention. In this embodiment, the gate and drain node of the NMOS transistor 704 in the keeper circuit 702 are connected to the power supply node Vdd and its source node is connected to the bit line 208 a and/or 208 b through a PMOS transistor 706 .
FIG. 7B is a schematic diagram of a variation of the sense amplifier circuit show in FIG. 7A . In this embodiment, the gate and drain node of the NMOS transistor 714 in the keeper circuit 712 are connected to the power supply node Vdd and its source node is connected to the bit line 108 a and/or 108 b through a PMOS transistor 716 .
FIG. 8 is a schematic diagram of yet another embodiment of the sense amplifier circuit 800 according to the present disclosure. In this embodiment, the source node of the NMOS transistor 804 in the keeper circuit 802 is connected to the power supply node through a PMOS transistor 806 and its drain node is connected to the bit line 208 a and/or 208 b . The gate node of the NMOS transistor 804 is connected to the power supply node Vdd. According to this embodiment, the noise threshold control circuit 808 including strong NMOS transistors 810 are connected in parallel to conventional NAND gate 206 to lower the trip point of the sense amplifier output 212 by effectively lowering the value of β of the NAND gate 206 .
Although the present invention and its advantages have been described in detail, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the invention as defined by the appended claims. For example, a single bit line circuit instead of a pair of bit-line circuit as shown in FIGS. 2-3 , 6 - 9 can use an inverter with a single input and output instead of NAND gates with two inputs.
Moreover, the scope of the present application is not intended to be limited to the particular embodiments of the invention described in the specification. As one of ordinary skill in the art will readily appreciate from the disclosure of the present invention, any development, presently existing or later to be developed, that perform substantially the same function or achieve substantially the same result as the corresponding embodiments described herein may be utilized according to the present invention. Accordingly, the appended claims are intended to include within their scope such developments. | In at least one embodiment, a sense amplifier circuit includes a pair of bit lines, a sense amplifier output, a keeper circuit, and a noise threshold control circuit. The keeper circuit is coupled to the pair of bit lines and includes an NMOS transistor coupled between a power node and a corresponding one of the pair of bit lines. The keeper circuit is sized to supply sufficient current to compensate a leakage current of the corresponding bit line and configured to maintain a voltage level of the corresponding bit line. The noise threshold control circuit is connected to the sense amplifier output and the pair of bit lines. The noise threshold control circuit comprises a half-Schmitt trigger circuit or a Schmitt trigger circuit. | 6 |
TECHNICAL FIELD
This disclosure relates to an apparatus and methods for cleaning large quantities of kitchenware, dishware, tableware, flatware, dinnerware, hollowware, utensils, and the like. More particularly, the disclosed apparatus and methods relate to a mobile, easy to assemble and disassemble, environment-friendly, heavy duty mass dishwasher system that utilizes blasting technology for effectively and thoroughly cleaning large quantities of pots, pans, plates, dishes, utensils and the like in areas with a scarce fresh water supply and aboard marine ships, without surface wear, damage or breakage of fragile items, without the use of chemical detergents and in a manner substantially limiting the use of water and eliminating waste streams.
BACKGROUND
Throughout this disclosure, the terms dishes and dishware will be considered to include water washable kitchenware, dishware, tableware, flatware, dinnerware, hollowware, utensils and the like commonly used for preparing, cooking, serving and consuming meals. The terms mobile and nomadic will refer to an apparatus that is self-contained, has a relatively small foot print, is skid-mounted or trailer-mounted, is easy to assemble and disassemble and can be moved from one location to another. The terms mass and high volume will refer to an apparatus that is designed and constructed to operate in continuous or batch mode to serve a large group of people in a small community, a population pocket or a remote campsite, mess hall, cafeteria, aboard ship and the like. The use of this terminology is for simplicity in explaining the applicability of the enclosed apparatus and methods, unless specifically excepted.
Dishware cleaning is an important function in preventing the proliferation of potentially harmful bacteria, preventing the attraction of a variety of undesirable creatures, such as bugs, roaches, mice and rats, enhancing the aesthetics of dishware and for other health, cultural or appearance purposes. Water and detergent have frequently been the method of cleaning dishware. However, water is increasingly in short supply in many places in the world and detergent is relatively costly, can be difficult to transport, and has potential environmental affects. Furthermore, isolated population pockets and remote campsites as well as arid and desert regions lack ample freshwater resources and wastewater processing facilities. Ocean- and sea-going marine vessels have limited fresh water supply and harsh restrictions on disposal of gray water and black water at sea.
Sand and silica have also been a media of choice for scrubbing and cleaning kitchenware and dishware, particularly for camping dishware. Sand is still used today by nomads and scouts to remove stubborn grease and burned and hardened food particles from scorched surfaces, and to remove soot accumulating on pots and pans used for cooking on open fires, especially in situations where there is no detergent and very little water. Sand cleaning provides a shine on the surface of utensils and cookware, preserving the surface luster of copper and stainless steel pots and pans. Indeed, some detergents contain abrasive particles for washing highly soiled dishes and stained and grimy clothes. Some specialty soap may also contain abrasive particles for cleaning skin soiled by hard-to-remove lubricants and crude oil.
Thus, fine sand and silica particles may be used in cleaning cookware, kitchenware and tableware whenever water and detergent are not available or do not provide the desired cleanliness of surfaces without extensive waste of resources and effort.
In rugged areas inhabited by nomads, remote desert pockets of population, arid land and wasteland, people are crowded around very limited water sources, where utility services are often beyond reach. Such areas are often the preferred locations for military and civilian camps. In these areas, cleaning cookware and food service ware is difficult and the logistics of constructing water wasteful and detergent demanding dishwashing systems with adequate plumbing are rather complex.
To reduce the amount of water required to clean pots and pans in the battlefield, Muller et al. proposed a chemical sanitation system that effectively cleaned and sanitized pots and pans at cold water temperatures, 15 to 20 degrees Celsius, as reported in Wayne S. Muller et al., Chemical Sanitation System for Pots and Pans in Field Operations, report #NATICK/TR-89/020, U.S. Army Natick Research, Development, and Engineering Center, Natick, Mass. (February 1989). While effective at sanitizing, this system had difficulty removing grease at this temperature range. At this time, no commercial product or combination of products available can effectively clean all types of food residue from pots and pans at these temperatures.
McCormick, et al. developed a procedure to clean and sanitize kitchenware in ambient cold water during emergency situations, in which dirty pots, pans, and kitchen utensils could be successfully cleaned and degreased, starting by hand-scrubbing the kitchenware in a sink containing a 5% solution of a commercial cleaner/degreaser at 15 degrees Celsius, as reported by Neil G. McCormick and R. G. Flaig, Cold Water Cleaning and Sanitizing of Kitchenware in the Field, report #NATICK/TR-90/013, U.S. Army Natick Research Development, and Engineering Center, Natick, Mass. (December 1989). The scrubbed article was then rinsed in a sink filled with water held at 15 degrees Celsius and sanitized in a third sink containing a 15 degrees Celsius solution of a commercial quaternary ammonium sanitizing agent. Results from swab tests performed on processed articles showed the number of bacteria to be well below the permissible level, if not completely absent. The procedure was judged highly successful in cleaning, degreasing and sanitizing kitchenware in cold water. This same procedure also successfully cleaned and sanitized individual mess gear in a field test situation using water at 20 degrees Celsius. However, using such a chemical procedure creates pollution problems with the disposal of gray water and the chemicals used to clean the kitchenware.
Certain solvents, along with a surface wetting agent, may replace water detergent in a process similar to dry-cleaning clothing. Furthermore, some solvents used in dry-cleaning, such as tetrachloroethylene (TCE) and Stoddard solvent, can remove various types of stains and grease and thus may have potential uses for cleaning dishware. Nash et al. found that certain surfactants are especially useful for degreasing and removal of oils as reported by J. Nash et al., Surfactant-Enhanced in Situ Soils Washing, report #AFESC/ESL-TR87-18, Engineering and Services Lab, Air Force Engineering and Services Center, Tyndall AFB, Fl. (1987). As these chemicals are of relatively small volume relative to the amount of water used in traditional processes, such chemicals would be fairly easy to store and reusable after filtering.
Accordingly, there is a need in desert population centers, either temporary or permanent, for a dishwashing system that is easy to assemble and to disassemble and provides service for large groups on as-needed basis, while preserving limited vital resources such as water, causing no pollution to those resources, and requiring very little supply of consumables.
In order to understand the background of dishwashing better, hereinbelow are a variety of situations concerns associated with cleaning in general and cleaning dishes specifically, along with current techniques and needs.
Conventional Dishwashing Mechanisms
Conventional dishwashing processes are often a multi-stage process. The first stage may be a manual rough scrubbing. This scrubbing is often carried out by scrubbers with large, coarse bristles, the purpose of which is to remove large food residue. Note that modern dishwashing machines allow for the presence and removal of large food residue. After the rough scrubbing step, manual fine scrubbing of the remaining residue and stains takes place, using scrubbers with fine bristles, by hot water jets or nozzles or by a combination of both. In the next stage, a combination of hot water and detergent in the form of jets or sprays clean residues such as grease, soil, and small food particles, as well as the liquid films that may form when the aforementioned residues combine with water. Next, the dishware receives rinsing and sanitizing using hot water. In a final stage, water may drain from the dishware and hot air may blow on the dishware to aid in removal of bulk water and to speed drying of the dishes. As a separate step and possibly in parallel to the aforementioned steps, residue and waste are carried in water or are dissolved in water and are drained from the dishwashing apparatus, possibly with the aid of partial vacuum pressure or suction. One or more portions of the aforementioned steps may be automated. The trend in home appliances is to automate the entire process fully. In general, most dishwashing processes would include stages of scrubbing, degreasing, de-staining or fine scrubbing, dishware cleaning, sanitizing, drying, and disposal of liquid/slurry waste, including food debris.
Environmental Challenges of High Volume Dishwashing
Typically, the procedures followed to clean dishware in a large mess hall or a cafeteria capable of feeding many people involve placing dishware, including ware for bulk food preparation, in a rack and positioning the rack, which may be full, on a conveyor belt of the dishwasher. The conveyor belt then moves one or more racks to a location between water jet nozzles positioned above and below the rack. The water jet nozzles remove loose food residue from the dishware. During the first stage of the wash cycle, detergent from an attached dispenser dissolves in pressurized heated water at about 71 degrees Celsius, which then sprays from the nozzles to remove food residue from the dishware. The racks continue along the conveyor belt to a rinse stage, passing through a second set of water jet nozzles located above and below the conveyor, which spray pressurized water at about 82 degrees Celsius to rinse and sanitize or sterilize the washed dishware. After passing through the rinse stage, racks may be stacked with clean dishes ready for use or an operator may remove the dishes from the racks and store them or position them for reuse. Some dishwashers may have a drying step or stage. The configuration of racks allows water to drain from the racks and permits airflow to assist in and accelerate the drying process.
The main advantage of the conveyor system is that it enables dishware to be washed quickly and continuously through a systematic and mostly automated process without interruption. The user of the dishwasher may then use fewer dishes, utensils, pots, pans, flatware, etc., i.e., dishware, to serve a large number of people since the dishwasher quickly returns dishware to service. A conveyor dishwasher also reduces the labor required to clean dishware. This system is particularly useful when feeding large numbers of people over an extended long period. Thus, multiple eaters may use a single item of dishware during a single day and potentially a single meal because of the rapidity with which a dishwasher may restore dishware to service.
While high volume dishwashers provide advantages in efficiency and speed, especially in situations involving mass feeding and batch feeding, they also consume tremendous amounts of freshwater even when a filtration system recycles rinse water for reuse. These systems also discharge large volumes of wastewater, which exacerbates the problem of mass effluent disposal. While wastewater can drain directly to an existing storm sewer system, chemicals in wastewater may cause pollution problems at the location where the wastewater discharges. Even treatment of the wastewater may leave residual chemicals in the filtrate and produce a secondary stream containing suspended or dissolved chemicals. In arid zones and rural areas, wastewater discharge may seep directly to the ground, potentially polluting the water table. Though biodegradable detergents theoretically reduce pollution, the time it takes for the detergents to become inert may allow the detergents to accumulate in the water table or the local ground water supply.
Thus, in addition to the need for a dishwashing system for arid zones or remote areas, there is a second need for such a dishwashing system to reduce the volume of both freshwater used and wastewater produced, particularly in areas with scarce freshwater supplies and no or inadequate wastewater disposal facilities. In addition, the waste generated from a dishwashing apparatus should be minimized by recycling and disposed of in an environmentally friendly manner.
Marine and Shipboard Cleaning of Dishware
The discussion of needs thus far has generally focused on remote, water-scarce, and arid regions. However, ships having a dishwashing capability present a similar and significant challenge. Typically, the dishwasher in a large ship's scullery contains two water tanks with heating elements to warm water used for cleaning dishware. One water tank holds a mixture of detergent and water for cleaning, while the other tank holds rinse water. While the water in each tank may be used multiple times during a given meal, the scullery system's tanks are usually drained and cleaned at the end of a meal. Since the runoff water from the dishwasher becomes contaminated with detergent and food matter, the water is considered gray water and must be stored for later disposal along with similar waste water collected from the galley, laundry, showers, sinks and other miscellaneous shipboard sources while a ship is operating within a protected zone of a country's coastal waters. A ship serves three meals per day in port and four meals per day when underway, thus generating significant quantities of gray water. The volume of gray water produced by the scullery is a significant portion of total gray water produced, as a typical large ship serves three meals per day in port and four meals per day when at sea.
Other dishwashers may exist aboard a ship, such as those in the wardroom pantry or in the captain's room. These other dishwashers may use different procedures, but still use a significant volume of fresh water and still produce a significant volume of gray water. The manual operation of these dishwashers proceeds as follows. First, the drains are closed. Second, the doors are closed. Third, the tank fill switch is set to an “on” position. Fourth, the tank will fill for about three minutes, and then the tank fill switch is set to the “off” position. Fifth, tank heat is set to an “on” position and the operator will wait for the tank to reach a temperature of about 66 degrees Celsius. Sixth, the operator opens the dishwasher door and the operator will place a rack loaded with dishes into the dishwasher. Seventh, the operator will close the dishwasher door. Eighth, the operator will activate the “start” switch to cause the dishwasher to operate through a complete cycle, which may contain one or more wash and rinse cycles. Ninth, the operator will remove the rack. The operator will then repeat the sixth, seventh and eighth steps. The dishwasher tanks require draining after each cycle. These dishwashers generally employ water jets to remove food debris, to clean, to rinse, and to sterilize dishware, simultaneously producing gray water.
Effluent from dishwashers may represent more than 25% of a marine ship's generated gray water. Dishwashers contribute significantly to the size and cost of subsequent shipboard treatment systems as well as the requirement for freshwater. The problem of shipboard gray water has been of concern in terms of characterizing gray water waste, evaluating shipboard waste treatment units, assessing the environmental affect of gray water treatment, evaluating shore-side waste disposal facilities, and assessing the technical and economic effects of gray water treatment and retention. On some ships and in some situations, gray water may drain to the sanitary sewage system, increasing the volume of that type of wastewater.
Tighter regulations due to legislation, such as the Clean Water Act and the Marine Protection, Research and Sanctuaries Act (MPRSA), which govern estuaries, coastal waterways, and the open ocean, and international conventions such as the London Dumping Convention, the 1974 Oslo Convention, and the International Convention for Prevention of Pollution from Ships (MARPOL), make the need for stringent control of waste streams in naval and marine vessels imperative to prevent loss of access to foreign or domestic ports. If a ship or vessel is unable to comply with operational or homeport restrictions in environmentally sensitive waters, then costlier alternatives to shipping by water may be required.
Thus, there is a need for a dishwasher that significantly reduces use of fresh water on civilian and military ships and subsequently reduces the storage space required for fresh water. Elimination or substantial reduction of dishwashing water effluent would also reduce the volume of gray water, minimizing gray water storage space and simplifying the logistics of gray water disposal. Disposal of gray water at sea is no longer possible due to potential hazards to marine life and the possibility that gray water may drift to shore, in addition to both domestic and international laws governing the disposal of waste in domestic and international waters. At the same time, a dishwashing system with little or no wastewater effluent aboard ships would enable ships to hold gray water for greater periods without the need for onboard treatment system. Alternatively, the overall volume of gray water has to be reduced as well by filtration and recycling to minimize the space required for storage of the produced gray water.
Home Dishwashing
Small dishwashing units such as those used in homes are closed systems that operate slightly differently as compared to mass dishwashing systems. These smaller units lack a flow-through design, which is unnecessary because home meals typically use fewer total dishes or dishware. However, as with larger dishwashing units, small dishwashers also typically contain nozzles for a mixture of detergent and water and for rinse water. Because of space considerations in a home, home dishwashers lack a conveyor system and may have only one tank, requiring draining of water between a cleaning cycle and a rinse cycle rather than reuse. Dishes cleaned in a dishwasher require approximately 37% less water than those washed by hand. If a sink's washbasin and rinse basin contain standing water rather than permitting an associated faucet to run, hand washing may use as little as half as much water as a dishwasher. However, hand cleaned dishware should still have a sterilization step of some type, either with sufficient heat to kill germs or some other means.
Most modern dishwashing appliances have several dishwashing cycles that may be appropriately selected to meet the requirements of a specific load of dishware depending on the soil conditions of the dishware. Selecting a cycle designed to clean more food residue or a cycle longer than necessary will unnecessarily increase water or hot water consumption and will waste energy, water and detergent while incurring additional and unnecessary cost for the superfluous inputs. In contrast, choosing a cycle insufficient for the soil condition of dishware may result in the dishware being inadequately washed, possibly requiring subsequent washing either by hand or through another dishwashing cycle. “Smart” dishwashers that detect the soil condition of a load and then select a dishwashing cycle pattern that matches the soil condition may mitigate or prevent improper cycle selection, reducing wasted energy, water and detergent.
Typical dishwashers need water sufficiently hot to melt dishwasher soap, which melts faster and more thoroughly at higher water temperature, and to clean dishes contaminated by grease. An optimal temperature might be 60 degrees Celsius. As much as 80% of the energy used by a dishwasher is used to heat water. This energy usage may be reduced by using a dishwasher with a booster heater that provides water hot enough to sanitize dishware with the home's water heater set at about 49 degrees Celsius. Furthermore, using a smaller volume of water consumes less energy to heat, reduces the amount of water needing treatment to make it suitable for use as wash water, reduces the amount pumped to the home, and decreases the amount needing treatment at a waste facility. Supplying water and treating water after use can be up to 50% of a typical city's energy bill.
Thus, there is a need in the art to develop a domestic dishwasher that reduces water consumption for even a “heavy soil” cycle, which would save energy and money for both the end user and the utility supplier.
Environmental Concerns
Water Input and Output
Minimizing wastewater on land is also becoming a high priority in many areas due to wastewater produced by mass dishwashing systems typically used in institutional kitchens, large food service facilities, and dining facilities. A large volume of wastewater poses particular problems in areas with a limited supply of fresh water combined with expansion in wastewater production. In and areas, scarcity of water requires strict fresh water conservation measures. Furthermore, campsites are often located in areas with a scarcity of water. Thus, any water saving device or method that helps to reduce the total volume of water demanded is desirable.
Operators of dishwashers, whether commercial or domestic, differ in the way they prepare the dishwasher load. Some operators scrape loose soil and food particles from dishware, while some use detergent to assure dissolving of grease and scum and to remove any grime that may accumulate when dishware sits for some time before cleaning Other operators soak dishware in a sink filled with detergent-laden hot water and rinse most or all dishware thoroughly before loading the dishwasher. Thus, dishwashers are often times used just for sanitation, which is an extremely water-wasteful practice and is often very wasteful of energy, if the water used for sink soaking and rinsing has been heated. The gray water byproduct from preparation for the dishwashing machine may exceed the gray water rejected by the dishwashing machine throughout the washing cycle.
To alleviate the effect of such wasteful practices, to conserve water and energy, and to reduce the environmental burden while enhancing the economics of operation, dishwashers may include a “rinse and hold” detergentless short rinse cycle to remove loose soil from partial loads after scraping, flushing loose soil and gray water down the drain.
Commercial and domestic dishwashing systems use a variety of chemical detergents to break down grease and scum. The presence of chemicals in addition to food particles and oils in the gray water stream complicates the disposal and treatment of the wastewater. Any amount of detergent over that needed for a given load will result in a relatively large amount of unused detergent discharge along with the gray water, causing environmental pollution. In addition, detergent molecules attach themselves to soil particles and accompany those soil particles into the environment. While there has been a trend toward using detergents and surfactants without a record of harming the environment, these detergents and surfactants only change the composition of chemicals in the wastewater; the quantity of chemicals released remains comparable and the flow of spent chemicals polluting the environment continues. Although biodegradable detergents minimize the environmental effect of releasing wastewater to the environment, the presence of detergent in the waste stream still requires special handling.
Thus, there is a need in the appliance industry for a dishwasher that can be partially loaded with dishware after scraping off loose food particles and operates only when the dishwashing unit is fully loaded, without requiring pre-removal of soil, detergent or a rinse-and-hold cycle.
There is also a need for a waterless dishwasher or a dishwasher that consumes minimal quantities of fresh water to clean kitchenware and dishware generally and in fresh water-scarce areas in particular.
There is also a long recognized and unfilled need to reduce the amount of polluting detergent chemicals discharged into the environment and to reduce secondary waste streams. A preferable dishwashing apparatus or method would avoid the use of chemical detergent.
Environmental Concerns
Energy Usage
In dishwashers, the washing cycle requires a large amount of energy. This energy includes that used by the hot water heater and the electrical energy used to run both the dishwasher pump and the resistance-heating element enclosed in the dishwasher to boost the water temperature and to dry the dishware. In a normal cycle, a typical domestic dishwasher requires about 34.5 liters of water per load. The hot water used by such a dishwasher is first warmed by a hot water heater from a home's cold water source that may have a temperature of 10° C.-20° C. to the hot water heater's water temperature of at about 49° C. Each dishwasher load requires about six fills of fresh hot water, ranging from approximately 5.3 liters to approximately 7 liters. The first two fills are needed for pre-wash cycles, followed by a fresh fill for the main wash cycles. The last three fills are needed for two post rinse and one final rinse cycles. Assuming a perfectly efficient heating process, raising the temperature of the water by an increment of 29 to 39 degrees Celsius requires 1.13-1.53 kWh of water heating energy, which is directly proportional to the water volume. The average mechanical energy consumption per cycle is approximately 0.65 kWh. The average total energy consumption for a regular dishwashing cycle is from approximately 1.78 kWh to approximately 2.18 kWh. Home dishwashers do not normally reuse water from one cycle to the next. Reusing or recycling hot water from one cycle to the next cycle would require at least a screen and centrifuge to separate soil particles from the water. The screens are inefficient and impractical since they need frequent removal and cleaning to prevent bacterial growth and accumulation of scum, while the moving parts of the centrifuge require additional space and energy as well as periodic maintenance in order to continue to remove particles from the water effectively.
Commercial heavy-duty dishwashing machines, such as those used in the scullery, in cafeterias, in a military mess, or in large dining facilities employ a conveyor belt to move racks of dishes between water jet nozzles positioned above and below the rack in order to remove food and residue from dishware. During the first part of the cycle, heated water at about 71° C. and detergent is sprayed through high-pressure nozzles to clean the dishware. During the second part of the cleaning cycle, hotter water at 82° C. is sprayed under pressure to rinse and sterilize the washed dishware. Commercial and institutional environments require sterilization at much higher temperatures than do home appliances due to a risk of contamination and bacterial growth. Commercial and institutional dishwashing systems also require much larger quantities of water than home dishwashers require and thus incur the energy expense of heating a correspondingly larger volume of water. In commercial and institutional settings, dishware is often heavily soiled, producing wastewater that contains significant amounts of food particles. Ultra-filtration units are needed to quickly remove suspended or dissolved solids from this water so that it may be recycled or reused, requiring a significant additional energy cost to offset the savings in not having to heat as much water.
U.S. Pat. Nos. 6,343,611 and 6,001,190 to El-Shoubary et al. describes a dishwasher having a standard normal operating cycle. The dishwasher includes a container for accommodating a plurality of articles, a circulation pump for delivering a liquid to the container and for circulating the liquid within the container, and a diverter connected to the circulation pump for diverting at least a portion of the circulating liquid to a hydroclone. At least 90% of the liquid diverted to the hydroclone returns to the circulating liquid, the returned liquid having at most about 0.02% solids.
Several dishwasher improvements were introduced to enhance the cleaning efficiency, to reduce energy or to reduce water use. U.S. Pat. No. 5,947,135 to Sumida et al. relates to simultaneously producing two kinds of ionized water for use as washing water without being discarded before use, so that water saving can be achieved. When tableware is washed and rinsed in a dishwasher, the tableware is washed within ten minutes using acid ionized water having a pH value of at most 6.0 and a temperature of at least 40 degrees Celsius in a first washing step, whereby dirt coheres and thus is prevented from being reattached to the tableware so that a washing load in the following washing steps is reduced. Next, the tableware is washed for at least fifteen (15) minutes with alkaline ionized water having a pH value of at least 8.5 and a temperature of at least 55 degrees Celsius in at least one of the washing steps, whereby the washing effects on fats and oils, protein and starch are improved. While the two kinds of ionized water are being produced simultaneously, one batch of ionized water is supplied to a washing vessel for use in the present washing cycle and the other batch of ionized water is supplied to and stored in a water tank for use in the next washing cycle, so that two or more water tanks are not necessary, resulting in reduction in size of dishwashers and in manufacturing cost.
Accordingly, there is a need for reducing energy consumption during wash loads of dishwashers without significantly increasing the time required for cleaning or increasing the amount of freshwater required for cleaning. Reducing the volume of hot water used by a dishwasher decreases the amount of water that needs heating and would indirectly reduce the dishwasher's overall energy consumption.
Ultrasonic and High-Tech Cleaning
Ultrasonic cleaning and polishing of precious stones, jewelry and other fine articles is common. Ultrasonic cleaning typically uses a relatively small amount of water and chemicals. Ultrasonic cleaning of semiconductors, metal strips, fragile membranes, and delicate fabrics is also common, typically by enhancing the reactivity of cleaning agents and solvents with ultrasonic excitation. Though ultrasonic cleaning of larger items without detergent in conventional cleaning processes has remained a challenge, the production of small sized transducers and development of durable materials for transducers has enabled the creation of larger transducer-based ultrasonic cleaning systems. Ultrasonic excitation of dry cleaning solvents to clean delicate fabrics has also been successful. There has been research on the cleaning potential of ultrasonic vibrations for various types of detailed cleaning, but the research thus far still require the use of solvents and detergents.
The physical theory behind ultrasonic cleaning is based on acoustical cavitation in liquid films. The intense sound waves provided by ultrasonic transducers create alternating regions of compression and expansion in a liquid, forming bubbles with a diameter that is dependent on the frequency of the transducer. For example, the bubbles may have a diameter of one hundred microns (100 μm). If the bubble is of the critical size, as determined by the frequency of the ultrasonic waves, the bubble may implode violently, releasing energy and creating a localized hot spot with an approximate temperature of 5,500 degrees Celsius. Since this region is small, the heat dissipates quickly and the bulk of the liquid remains at ambient temperature or an elevated temperature if the ultrasonic cleaner includes a heater. As the bubbles at or near a surface implode, micron-sized particles can be released into the surroundings if the acoustical pressure of the transducers is of adequate magnitude, that is, if high power ultrasonic transducers are used. Transforming the residues on a surface to micron-sized particles for disposal is the basis of the ultrasonic cleaning process.
An ultrasonic dishwashing process may flow in the following sequence. Step 1: Manual or mechanical scrubbing of large food residue by scrubbers, brushes, or sand blasting. Step 2: The liquid film on the dishes, which includes water, grease and food particles, is subjected to an ultrasonic field, causing cavitation in the liquid film and “vaporization” of the film into very small droplets about 1 micron in size. The droplets take the form of a mist that carries water and small food particles away. Step 3: To dry the suspended food particles for disposal, the mist resulting from the ultrasonic process is subjected to another process such as heated air or an additional sonic field that causes a phase change in water. After the water has evaporated, the remaining dried food particles are collected for discarding. Step 4: A partial vacuum pressure withdraws the dried food particles.
The transducers in this process need to be close to the dishware. The sonification of the liquid film containing food residue will create a fine vapor that contains food particles or residue in solution or suspension. This method most closely resembles spray drying. The ultrasonic approach, however, results in finer particles, which promotes more rapid drying and lower dishware temperatures. In addition, limitations of spray drying, such as clogging and feed considerations, do not apply since ultrasonic energy accomplishes the atomization of food residue. Because of the short time required to accomplish cleaning, the speed and economy of this process should rival current freeze drying techniques while yielding high quality cleaning.
Step 1 and step 2 employed in the ultrasonic dishwashing process may be replaced by pulsating dry steam jets and timed sprayers that spray a grease dissolving agent in small quantities at the beginning of the cycle. This action is sufficient for washing dishes while producing minimum moisture. Following the dry steam jets and timed sprayers may be hot air jets to dry the dishware. Although this process will reduce water requirements compared to the ultrasonic method, an undesirable chemical waste stream will result from the grease-dissolving agent.
An alternative configuration is the use of ultrasonic nozzles, which will result in atomization of the liquid film and rapid, efficient drying. This process may replace step 2 described above.
An automated processing conveyor (similar to an assembly line) may be employed in moving dishware to a scrubbing station, a washing station, and then a drying station. The scrubbing will be similar to Step 1 above. The wash station may involve three stages. In the first stage, spraying nozzles spray a light mist of water with detergent, followed by a light scrubbing stage, and then a pure water mist spraying as a rinse stage. The drying station will use hot air. In this process, the dishes will be stacked in a manner that allows rotation and exposure of all surfaces. A sponge or cloth can achieve light scrubbing. In case of cups and utensils, special brushes have to be used for the scrubbing. Alternately, light scrubbing by blasting granules of sand or similar material is possible.
A thermal process similar to the mechanical process may be used in dishwashing with the exception of using an air current sweeping across the dishware to provide heating that can remove vapors and solidify food residues to a degree sufficient for removal through suction ducts. To increase heat conduction dishes may be assembled on trays. An alternative process may involve moving the dishes through a tunnel where heat is applied and vapors are removed. In most cases, air is used in tunnel drying and dishware can move through the dryer either parallel or countercurrent to airflow. Hot air nozzles may supply heat. Drying of the liquid film, grease or food residues occurs very rapidly. This process is useful for dishes sensitive to exposure to heat for any appreciable length of time.
U.S. Pat. No. 5,113,881 to Lin et al. describes an ultrasonic device for cleaning and disinfecting fruits and vegetables in a water-filled tank. U.S. Pat. No. 4,836,684 to Javorik, et al. describes an ultrasonic cleaning device that utilizes ultrasonic transducers and generators to clean items contained in a liquid bath in a tank above the transducer assembly. U.S. Pat. No. 4,461,651 to Hall describes a sonic cleaning device and method for removing accumulated particles using sonic energy vibrations. U.S. Pat. No. 4,367,098 to McCord describes a method that uses ultrasonic transducers and fluids of different densities. U.S. Pat. No. 4,193,818 to Young et al. describes a method and apparatus for ultrasonic cleaning in a sealed vessel capable of carrying out high-pressure sterilization. U.S. Pat. No. 4,834,124 to Honda discloses an ultrasonic cleaning device that is used to clean objects by a cleaning liquid using ultrasonic waves spouted from a spouting port without soaking the objects.
To reduce the volume of water and chemical detergents used in dishwashing and thus reduce the volume of gray water produced, there have been innovations in the ultrasonic cleaning of kitchenware and tableware items. For example, U.S. Pat. No. 5,218,980 to Evans describes an ultrasonic dishwashing system in which a controller rapidly varies the frequency of the ultrasonic signals and rapidly cycles the signals on and off. U.S. Pat. No. 3,854,998 to Jacobs discloses a fluid-powered ultrasonic washing, rinsing, and drying system for a dishwasher.
A partnership in the state of California formed between Southern California Edison and the California Division of Water Resources supported testing of a prototype ultrasonic dishwasher system manufactured by Ultrasonic Products, Inc., at the University of California at Santa Barbara. Ultrasonic dishwashers gently bombard grimy dish grease with sound waves. Instead of spraying, dishware is immersed in a tank of water and bombarded with high frequency sound waves that create tiny vapor bubbles to dislodge caked on grime, leading to a drop in hot water use by 25-50%.
Ultrasonic cleaning systems can save energy compared to traditional detergent-based dishwashers because they use lower water temperature and therefore use less energy. While ultrasonic cleaning reduces temperature and energy requirements, it still requires a cleaning solution and an appreciable amount of water in which dishware must be submerged for transfer of ultrasonic energy to cause the cavitation that effectively cleans soiled surfaces. Thus, there is a need for a dishwashing device that effectively removes food residue from dishware without the liquid transmission medium that ultrasonic cleaning requires. Another limitation on ultrasonic cleaning of dishware is that it generally requires the transducers to be near the soiled surface, which can limit the effective volume of cleaning Note also that cavitation and implosion in food residue film contaminates the cleaning medium, typically a combination of water and one or more cleaning solvents such as a surfactant or detergent. These food residues in solution or suspension must be collected, removed, and disposed.
Blasting and Dry Medium Cleaning
Abrasive blasting or sandblasting has long been a powerful cleaning technique, a process in which compressed air carrying abrasive particles rapidly strips away surfaces and thick coatings. Sandblasting removes rust from ferric metals and removes dirt from brick and other masonry. In more controlled applications, sandblasting cleans circuit boards and prepares surfaces to be painted. In combination with appropriate chemicals, abrasive blasting degreases components. Tuning of the power and precision of sandblasting is possible by varying air pressure, diameter of the nozzle, distance from the object, particle flow rate, and composition of the particles in terms of both size and material.
In traditional blasting based dishwasher machines, the blasting material must be recycled unless a huge amount of it is stored for extended operations. Reuse of silica-based blasting agents, such as sand or glass beads, is possible with separation and high temperature incineration of the media. Some of the medium will inevitably mix with food contaminants, but the medium, which is equivalent to sand, is environmentally safe and may be safely dump into seawater or a landfill without adverse effects. If the medium is plastic, a small amount of chemical cleaner or water cleans the plastic beads. Since the structure of the beads is unaffected by their use in cleaning, the beads are capable of being used multiple times with occasional refills to replace beads lost to structural failure, worn away by friction, and lost with disposal of food waste.
Using a non-disposable blasting medium to clean dishware requires a method of separating the blasting medium, which is capable of reuse, from food particles. The waste food particles and a small amount of the blasting medium may go into the trash, composted or other disposal techniques. Methods of separating food from blasting medium may include technologies such as gravity separation, inertia separation, centrifugal or cyclone separation, screen filtration, and incineration.
There have been previous attempts to recycle blasting media efficiently, which would be important in a dishwashing mechanism. U.S. Pat. No. 5,056,275 to Wada et al. describes a continuously operable hydraulic abrasive blasting apparatus including an abrasive storage tank, a recovery tank, and a hydraulic pressurized tank. One goal of this mechanism was to separate debris from an abrasive blasting medium so that the medium was capable of reuse. U.S. Pat. No. 4,382,352 to Nelson describes a blasting machine for cleaning surfaces, with a means to separate the blasting material from the debris and to clean and reuse the blasting material.
U.S. Pat. No. 4,804,488 to Alvemarker describes blasting bodies adapted for cleaning utensils in an admixture with dishwashing water, comprising about 60% by weight mineral filler selected from the group consisting of silicate, sulphate and carbonate, a plastic binder in the form of particles selected from the group consisting of polyamide and polyethylene, and at least 1% by weight chalk. The bodies in the medium, which are circular or polygonal in transverse cross section, each have a specific gravity of at least 2.0, a Moh hardness of at least 3.0, a mass of about 0.04 g, a length of about 3 mm, and a width of about 2.5 mm. The blasting bodies mix with dishwashing water and the mixture sprays against utensils from nozzles in a dishwasher to dislodge and remove residue. Upon completion of a cleaning cycle, the water typically passes through a sieve or strainer to separate the blasting bodies from the gray water. The bodies are collected for reuse. Alternately, the blasting bodies may settle in the machine as the dishwashing water is removed and are then reintroduced into the fresh dishwashing water. U.S. Pat. No. 5,735,730 to Jonemo at al. describes methods for separating granules from dishwater when the granules are heavier than the liquid, which would typically be water. U.S. Pat. No. 5,667,431 to Mortin describes an alternative dishwasher design employing washing liquid and blasting agents.
Issued patents describe certain wet blasting techniques in application to dishwashing such as U.S. Pat. No. 3,323,159 to Ummel et al., U.S. Pat. No. 3,272,650 to MacVittie, and U.S. Pat. No. 4,374,443 to Mosell. The blasting bodies used in dishwashing have the form of metal spheres, sand, crushed marble, or other heavy and hard blasting materials. Blasting bodies of such hardness, e.g. marble, are problematic in that they cause wear on washed utensils. On the other hand, blasting bodies may have the form of lightweight plastic pellets, which float in dishwashing water. Relatively hard plastic, such as polyoxymethylene, may be the plastic used to form such pellets.
In U.S. Pat. No. 4,959,930, Tsutsumi describes a washing machine liquid detergent applied to shots having relatively low hardness, which are then impinged against an object to be washed. Although the machine is very effective in cleaning very dirty dishware, the use of blasting detergent shots and heated water, excess water, detergent and energy use would be problematic in many situations.
To limit the volume of freshwater consumed and the contamination and volume of wastewater produced, U.S. Pat. No. 5,657,501 to Refai appears to disclose washing by the use of at least one polycarbonate contact body along with soiled items to improve efficiency of the cleaning process. U.S. Pat. No. 4,333,771 to Altenschopfer et al. describes a detergent composition with a mechanical cleaning effect for hard surfaces, particularly cooking and baking utensils, comprising a mixture of granular particles, the granular particles consisting substantially of a powdered to granulated component of conventional mechanical dishwashing agents capable of rapidly dissolving or finely dispersing in water, and a granulated component comprising finely divided, water insoluble inorganic compounds. However, neither of these processes eliminates wastewater or cleans efficiently without chemical detergents.
U.S. Pat. Nos. 6,609,960 and 6,280,301 to Rogmark describes a granule dishwasher with easily removable granule collectors and a method of use. Soiled articles are placed in the treatment chamber to be washed with a mixture consisting of liquid and granules that is sprayed at the articles under high pressure.
Many blasting techniques require a chemical element, such as surfactants, detergents, or solvents, to do the majority of the cleaning, assisted by blasting agents. In such techniques, blasting merely assists the chemicals by increasing the available surface area and providing access to the bases of thick residues by removing their upper layers. However, such techniques usually require water to remove both the detergent and the excess blasting media, requiring a freshwater supply and gray water disposal.
A cleaning process using hard or heavy dry-blasting media as disclosed in prior art causes wear on utensils. On the other hand, wet blasting media require significant amounts of water to achieve a cleaning effect with their softer media, which serves more as a catalyst to the detergent-based cleaning process than as a cleaning agent. Thus, there exists a need for an improved dry blasting dishwashing system that does not cause wear of dishware and would significantly reduce or eliminate water use.
Other Dishwashing Systems
To reduce detergent use in dishwashing loads, U.S. Pat. No. 6,680,287 to Wisniewski, et al. and U.S. Pat. No. 6,689,736 to Thomas et al. describe a dishwashing, cleaning water insoluble wipe comprising a substrate impregnated with a cleaning composition containing a cellulosic polymer.
Berryman (2004) at the University of Alberta, Canada described the development of a waterless dishwasher in response to growing concerns over both unsustainable water consumption and the problem of diminishing urban living space. Dirty dishes are placed on a retractable rubber conveyor. Upon activation, the conveyor automatically enters the cleaning unit. A blast of ultraviolet light first flash hardens food particles on a dish and kills bacteria. A sonic pulse is then applied that breaks down food particles and dislodges them from the dish. An electrostatic magnet then removes the vaporized particles before the dish exits the unit along the conveyor, spotless and bacteria-free. Besides saving much more space than a traditional dishwasher saves, cupboard space does not need to be cluttered with excess kitchenware since the instant cleaning action makes a build-up of dishes a thing of the past.
Douglas Nash, Ross Nicholls and Oystein Lie, students from the University of New South Wales in Australia, designed the Rockpool, a waterless dishwasher concept (Fitzgerald, 2005; Anon, 2004) that reduces strain on the environment and addresses consumers' concern for water use and the inconvenience of loading and unloading dishes in traditional dishwashers. Supercritical carbon dioxide is used in a closed-loop operation to clean the dishes. Under pressure, the carbon dioxide takes on special properties of a liquid and a gas so it dissolves grease and oil and it has no surface tension so it will cover everything, like a gas. The Rockpool is quiet since there are no moving parts. Supercritical carbon dioxide has been used in some industrial cleaning processes, but this is the first time it has been considered for a dishwasher. NASA is examining similar technology for cleaning processes on manned missions to Mars.
Generally, remote population pockets, campsites, nomadic or mobile communities, desert and arid regions suffering from lack of water, utility services and wastewater processing facilities have a great need for an energy-saving mobile dishwashing system for temporary or routine use that minimizes the amount of water consumed and requires no detergent. There is an even greater need aboard ships for a dishwashing system that is easy to operate and maintain, space-efficient, capable of cleaning dishware at the same rate as traditional dishwashing systems and compatible with the logistics of operation at sea, whether during times of peace or war.
Prior art references fail to disclose an environmentally friendly dishwashing system, requiring neither detergent nor water, that can operate continuously to clean and sanitize mass quantities of dishware without producing liquid, chemical, or secondary waste, and neither breaks nor abrades the surface of dishware being cleaned. Furthermore, none of the prior art describes a dry method of using fine natural sand or fine glass or plastic beads to clean kitchenware.
Thus, there is a yet unfulfilled need for a dishwashing system that produces minimal or no gray water or secondary waste streams, is user-friendly, is energy and cost efficient, has minimal life cycle cost, is acceptable by the user, removes grease and residual food particles, and leaves behind a minimum of post-cleaning spots and stains while keeping bacteria that may be on the dishware well below the permissible level.
SUMMARY
This disclosure provides an apparatus for washing dishware contaminated by food residue, including grease and water. The apparatus comprises a blasting medium storage system including a blasting medium. The apparatus further comprises a blasting medium transport system connected to the blasting medium storage system, the blasting medium transport system including a blasting medium delivery system. The apparatus further comprises an enclosure housing a carriage rack transport system, a portion of the blasting medium delivery system, and having a lower compartment. Blasting medium from the blasting medium storage system is moved from the blasting medium storage system by the action of the blasting medium transport system to the blasting medium delivery system located within the enclosure. The blasting medium delivery system directs blasting medium at a carriage rack supported by the carriage rack transport system. The used blasting medium and food residue falls into the lower compartment.
This disclosure also provides a dishwashing apparatus for washing dishware contaminated by food residue including grease and fatty acids. The apparatus comprises an air compressor, a feed valve connected to the air compressor by a first conduit, and a dividing manifold connected to the feed valve by a second conduit. The apparatus further comprises a first rail manifold connected to the dividing manifold by a third conduit, a second rail manifold connected to the dividing manifold by a fourth conduit, a first plurality of pressure heads connected to the first rail manifold, a first plurality of pressure nozzles, wherein every one of the first plurality of pressure heads has at least one pressure nozzle extending therefrom, a second plurality of pressure heads connected to the second rail manifold, and a second plurality of pressure nozzles, wherein every one of the second plurality of pressure heads has at least one pressure nozzle extending therefrom. The apparatus further comprises a blasting medium storage system. The blasting medium storage system includes a feed hopper and a fifth conduit connecting the feed hopper to the dividing manifold. The apparatus further comprises an enclosure, wherein the first rail manifold and the second rail manifold are positioned within the enclosure, a carriage rack transport system positioned in the enclosure, wherein the carriage rack transport system is configured to guide a carriage rack containing the dishware to a position longitudinally between the first plurality of pressure heads and the second plurality of pressure heads, and a return system located in a lower compartment of the enclosure, the return system including an angled portion. The components of the apparatus are connected in a manner that allows ease of assembly, disassembly and maintenance. Assemblage and communication between components of the apparatus provides as small footprint as possible for skid-mounting, vehicle-mounting and ease of transport from one location to the other. A blasting medium is transported through the fifth conduit to the feed valve by the action of compressed air from the air compressor flowing through first conduit and the feed valve. A combination of compressed air and blasting medium then flows through the second conduit, the dividing manifold, the third conduit, the first rail manifold to flow through the first plurality of pressure heads and then through the at least one pressure nozzle extending from every one of the pressure heads of the first plurality of pressure heads, and in parallel through the fourth conduit, the second rail manifold to flow through the second plurality of pressure heads and then through the at least one pressure nozzle extending from every one of the pressure heads of the second plurality of pressure heads. The combination of compressed air and blasting medium flows under pressure from the pressure nozzles to flow into the enclosure to impinge on the dishware in the carriage rack positioned in the carriage rack transport system. The action of the compressed air and blasting medium removes food debris from the surfaces of the dishware and the blasting medium and the food debris falls into the lower compartment to land on the angled portion.
This disclosure also provides a method of cleaning dishware without water or detergent. The method comprises placing the dirty dishware in an enclosure, forming a mixture of compressed air and a blasting medium in a blasting medium transport system, moving the mixture of compressed air and the blasting medium into the enclosure with the blasting medium transport system, directing the mixture of compressed air and the blasting at the dirty dishware to remove food residue using a blasting medium delivery system, and gathering the used blasting medium and the food residue for recycling or disposal in a blasting medium recovery system.
Advantages and features of the embodiments of this disclosure will become more apparent from the following detailed description of exemplary embodiments when viewed in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a stylized perspective view of a waterless dishwashing machine in accordance with a first exemplary embodiment of the present disclosure with some elements transparent to disclosure inner elements of the waterless dishwashing machine.
FIG. 2 is a side view of the waterless dishwasher system of FIG. 1 with a portion of an enclosure of the waterless dishwasher system removed to show the interior components of the enclosure.
FIG. 3 is a perspective view of a first end of the waterless dishwasher system of FIG. 1 .
FIG. 4 is a perspective view of a waterless dishwasher system in accordance with a second exemplary embodiment of the present disclosure having an optional rinse and sanitizing stages and an optional collection separation stage.
FIG. 5 is an elevation view of a first optional conveyor system in accordance with an exemplary embodiment of the present disclosure.
FIG. 6 is an elevation view of a second optional conveyor system in accordance with an exemplary embodiment of the present disclosure.
DETAILED DESCRIPTION
As will be seen, the present disclosure introduces improvements over existing dishwasher systems and practice since the primary washing is accomplished with dry blasting and does not require any water or detergent and does not produce any primary or secondary wastewater streams. A minimal amount of water may be used for the rinse cycle and for sterilization or sanitizing, which may be accomplished by steam or heated air.
Referring now to FIGS. 1 and 2 , there is illustrated a dry blasting dishwasher system 10 of the present disclosure. Dishwasher system 10 includes a blasting medium delivery system 12 , a dishwashing system 14 , and a blasting medium recovery system 16 .
Blasting medium delivery system 12 includes a blasting medium storage system 18 and a blasting medium transport system 20 . Dishwasher system 14 includes an enclosure system 22 , a blasting medium delivery system 24 , and a rack transport system 26 . Blasting medium recovery system 16 includes a return system 28 and a recovery storage system 30 .
Blasting medium storage system 18 may further include a blasting medium replenishment hopper 118 . A replenishment conduit 32 connects replenishment hopper 118 with a feed hopper 113 . A feed conduit 34 connects feed hopper 113 to a feed valve 114 , which is part of blasting medium transport system 20 .
Blasting medium transport system 20 includes an air compressor 111 , which connects to feed valve 114 by a compressor conduit 112 . Feed valve 114 connects to a dividing manifold 115 by a feed valve conduit 36 . A first manifold conduit 116 and a second manifold conduit 117 connect manifold 115 to a blasting medium delivery system 24 . Blasting medium delivery system 24 includes first rail manifold 38 , second rail manifold 40 , a plurality of pressure heads 101 , and a plurality of pressure nozzles 102 . First manifold conduit 116 connects to first rail manifold 38 . Second manifold conduit 117 connects to second rail 40 . First rail manifold 38 and a second rail manifold 40 are located within dishwashing system 14 . First rail manifold 38 and second rail manifold 40 supply and may connect directly or indirectly to a plurality of pressure heads 101 . Each pressure head 101 includes one or more pressure nozzles 102 extending therefrom. Pressure nozzles 102 may be generally parallel to each other, or may be at varying angles to each other, as shown in FIG. 2 .
Enclosure system 22 may include enclosure 105 that may have a stand 42 for support. Enclosure 105 may be formed of metal or a light transparent material to permit visual monitoring of the washing process to identify problems quickly. The light transparent material may be poly(methyl methacrylate), also called PMMA or acrylic glass. Enclosure 105 has seals to limit the escape of a blasting medium 100 from enclosure 105 . As will be seen, each end of enclosure 105 has an opening 44 to permit access to the interior of enclosure 105 . Opening 44 a is at a first end of enclosure 105 and opening 44 b is at a second end of enclosure 105 . Opening 44 a and opening 44 b each have a covering, which may be in the form of flexible curtain barriers 106 , shown in FIG. 3 . Flexible curtain barriers 106 may be formed of a heavy rubber or a suitable flexible plastic.
Within enclosure 105 is a plurality of pressure heads 101 that are also a part of blasting medium delivery system 24 . The position of pressure heads 101 may be at a top portion 105 a or at a bottom portion 105 b of enclosure 105 . However, pressure heads 101 may be located in other places within enclosure 105 . For example, pressure heads 101 may be located on a side portion 105 C of enclosure 105 . Pressure heads 101 may be in parallel rows, as shown in FIG. 1 , but they may also be in non-parallel configurations.
Along a longitudinal direction of enclosure 105 is rack transport system 26 . Rack transport system 26 may include a conveyor system, such as is shown in FIG. 4 , or it may be a manual system, as is shown in FIG. 1 . Rack transport system 26 may include a pair of guide rails 110 . A carriage rack 104 contains features that slidingly mate carriage rail 104 with guide rails 110 . Each carriage rack 104 contains features (not shown) for supporting dishware 103 . As previously noted, dishware 103 may include an array of items used in a kitchen, for example, metal pots, pans, plastic, china or metallic plates, cups, glasses, bowls, metal silverware, utensils, flatware, trays, etc. Dishware 103 is in addition to the carriage rack 104 that holds the dishes and passes through the dishwasher. The material of carriage rack 104 may be plastic.
Located adjacent to dishwashing system 14 is blasting medium recovery system 16 . Blasting medium recovery system 16 includes return system 28 located in a lower compartment 121 , which may be a gravity system that guides a blasting medium 100 to recovery storage system 30 . Return system 28 includes an angled slide or guide portion 48 . Angled slide or guide portion 48 may be at an angle to cause gravity to move blasting medium 100 along with any food debris toward recovery storage system 30 . Angled slide or guide portion 48 may be covered or coated with a friction resistant coating to enhance the movement of blasting medium 100 and food debris toward recovery storage system 30 further. Angled slide or guide portion 48 may also include a vibratory mechanism (not shown) to further encourage blasting medium 100 and food debris to move toward recovery storage system 30 .
Recovery storage system 30 removably interfaces with lower compartment 121 . The interface location is where angled slide or guide portion 48 positions used blasting medium 100 and food debris. Recovery storage system 30 includes an interface portion or spout 122 and a recovery reservoir 50 .
This system works in the following manner. An operator or user inserts a carriage rack 104 loaded with one or more dishware 103 through opening 44 a onto guide rails 110 . The operator or user then manually pushes carriage rack 104 into enclosure 105 . The operator or user may then load another carriage rack 104 , which may be loaded with more dishware 103 or may be empty, through opening 44 a onto guide rails 110 to advance the progress of the first carriage rack 104 containing the first load of dishware 103 .
Now that a loaded carriage rack 104 is within enclosure 105 , an operator or user turns on air compressor 111 in a first step. Compressed air flows from air compressor 111 to feed valve 114 by way of compressor conduit 112 . Feed valve 114 has at least two operational positions. In one position, compressed air flows through feed valve conduit 36 to dividing manifold 115 . In the other position, a combination of compressed air and blasting medium 100 flows through feed valve conduit 36 to dividing manifold 115 . After an operator or user loads a carriage rack 104 with dishware 103 into enclosure 105 , the operator sets feed valve 114 to supply compressed air only.
Compressed air flows into first manifold conduit 116 and second manifold conduit 117 by the action of dividing manifold 115 . Note that dividing manifold 115 may include a heating element (not shown) to raise the temperature of the pressurized air, thereby increasing the pressure of the air further. From first manifold conduit 116 , compressed air flows into first rail manifold 38 . First rail manifold 38 divides the flow of compressed air into multiple paths, flowing into a first plurality of pressure heads 101 . Once in the first plurality of pressure heads 101 , the compressed air flows through a first plurality of pressure nozzles 102 and then into the interior of enclosure 105 . From second manifold conduit 117 , compressed air flows into second manifold rail 40 . Second manifold rail 40 divides the flow of compressed air into multiple paths, flowing into a second plurality of pressure heads 101 . Once in the second plurality of pressure heads 101 , the compressed air flows through a second plurality of pressure nozzles 102 and then into the interior of enclosure 105 . The operator leaves feed valve 114 in this position for a period to dry preexisting moisture and to harden any food particles or residue sticking to dishware 103 to facilitate removal by blasting medium 100 .
After an operator or an optional sensor (not shown) determines air-drying is sufficient, the operator turns feed valve 114 to a second operational position for a second step. Associated with feed valve 114 is feed hopper 113 . Feed hopper 113 holds blasting medium 100 until feed valve 114 connects feed hopper 113 to feed valve conduit 36 while air compressor 111 is operating. The action of airflow through feed valve 114 draws blasting medium 100 through feed conduit 34 into feed valve 114 when feed valve 114 is in the second operational position. Blasting medium 100 will mix with compressed air from air compressor 111 and the mixture will flow into feed valve conduit 36 . Feed hopper 113 may be refilled manually at the end of one or more washing cycles or an optional blasting medium replenishment hopper 118 may automatically refill feed hopper 113 by way of replenishment conduit 32 .
A mixture of compressed air and blasting medium 100 flows into first manifold conduit 116 and second manifold conduit 117 by the action of dividing manifold 115 . Note that dividing manifold 115 may include a heating element (not shown) to raise the temperature of the pressurized air, thereby increasing the pressure of the air further. From first manifold conduit 116 , compressed air and blasting medium 100 flow into first rail manifold 38 . First rail manifold 38 divides the flow of compressed air and blasting medium 100 into multiple paths, flowing into a first plurality of pressure heads 101 . Once in the first plurality of pressure heads 101 , the flow of compressed air and blasting medium 100 flows through a first plurality of pressure nozzles 102 and then into the interior of enclosure 105 . From second manifold conduit 117 , compressed air and blasting medium 100 flow into second manifold rail 40 . Second manifold rail 40 divides the flow of compressed air and blasting medium 100 into multiple paths, flowing into a second plurality of pressure heads 101 . Once in the second plurality of pressure heads 101 , the flow of compressed air and blasting medium 100 flows through a second plurality of pressure nozzles 102 and then into the interior of enclosure 105 .
The orientation of the plurality of pressure heads 101 and the plurality of pressure nozzles 102 provide a distribution of blasting medium 100 to impinge on dishware 103 . The impingement of blasting medium 100 on dishware 103 causes the removal of food debris, including grease and fatty acids. Enclosure 105 , which includes flexible curtain barriers 106 , keeps the combination of food debris and blasting medium 100 contained. The action of gravity causes food debris and blasting medium 100 to fall through gaps 52 between pressure heads 101 in lower portion 105 b of enclosure 105 . Once through gaps 52 , food debris and blasting medium 100 falls into lower compartment 121 and then onto slide 48 . Because slide 48 is set at an angle, food debris and blasting medium 100 slides toward spout 122 of recovery storage system 30 . Once in spout 122 , food debris and blasting medium 100 falls into recovery reservoir 50 .
After sufficient time has passed to clean dishware 103 , an operator or user moves feed valve 114 to the first operational position to permit compressed air only to flow into enclosure 105 in a third step. The flow of compressed air into enclosure 105 clears any residual blasting medium 100 and food debris from dishware 103 . The flow of compressed air from compressor 111 also removes excess blasting medium 100 from compressor conduit 112 , feed valve 114 , feed valve conduit 36 , dividing manifold 115 , first manifold conduit 116 , second manifold conduit 117 , first rail manifold 38 , second rail manifold 40 , pressure heads 101 , and pressure nozzles 102 . The residual blasting medium 100 also falls through gaps 52 between pressure heads 101 in lower portion 105 b of enclosure 105 . Once through gaps 52 , the residual blasting medium 100 falls into lower compartment 121 , then onto slide 48 and then toward spout 122 of recovery storage system 30 , as previously described. Once in spout 122 , the residual blasting medium 100 falls into recovery reservoir 50 .
In order to enhance movement of food debris and blasting medium 100 along slide 48 , slide 48 may contain a shaker or vibrator (not shown). The action of such a shaker or vibrator would encourage food debris and blasting medium 100 to move downwardly along slide 48 toward spout 122 of recovery storage system 30 . The vibrator may be electrical or may be mechanical.
The steps of this process may benefit by moving the air from compressor 111 through a heating element (not shown). The heated air may assist in sanitizing dishware 103 . Yet another optional sanitizing configuration may use dry steam from a boiler, followed by pressurized hot air (not shown).
Following completion of the third step, the operator or user deactivates or de-energizes air compressor 111 . A brief wait permits residual dust that may include food debris and blasting medium 100 to settle into lower compartment 121 , limiting the amount of food debris and blasting medium 100 that escapes from enclosure 105 . Additional carriage racks 104 pushed into a first end of enclosure 105 push a loaded carriage rack 104 toward a second end of enclosure 105 . A loaded carriage rack 104 will eventually pass through opening 44 b through a flexible curtain barrier 106 at the second end of enclosure 105 onto an unloading platform 120 . Carriage rack 104 may be placed in a holding area so that dishware 103 may be used directly from carriage rack 104 , or dishware 103 from carriage rack 104 may be moved to storage cabinets or containers (not shown). While not shown, dry blasting dishwasher system 10 may include a loading platform adjacent the first end of enclosure 105 .
After completion of a cleaning cycle, an operator or user of dry blasting dishwasher system 10 may disconnect recovery storage system 30 from lower compartment 121 . Blasting medium 100 may now be recycled. If a silica or mineral-based blasting medium is employed, the collected mixture of blasting medium 100 and dried food particles and residue may be burned in a furnace to incinerate the attached organic material. If a separation process is used to recycle blasting medium 100 , food debris separated from used blasting medium 100 may be incinerated or placed in a trash or other disposal receptacle. Blasting medium 100 may be cleaned separately.
A second exemplary embodiment dry blasting dishwasher system 200 is shown in FIG. 4 . Dishwasher system 200 implements elements of the dry blasting system described in the first exemplary embodiment in a large semi-automated dishwashing system. Dishwasher system 200 includes a dishwashing system 214 , supplied by a blasting medium delivery system 224 and a sanitizing system 225 . Included within an enclosure 205 of dishwashing system 214 is a rack transport system 226 . Located below enclosure 205 is a blasting medium return system 228 . Return system 228 feeds into a blasting medium reclamation system 215 .
Many of the elements of this embodiment are similar to the first exemplary embodiment. Blasting medium delivery system 224 , located closer to a first end of enclosure 205 than a second end, connects to a blasting medium transport system that may be similar to blasting medium transport system 20 that may further connect to a blasting medium storage system that may be similar to blasting medium storage system 18 . Blasting medium delivery system 224 may include a first rail manifold 238 . First rail manifold 238 may connect to a plurality of pressure heads 201 . Each pressure head 201 may contain one ore more pressure nozzles 202 .
Located adjacent to blasting medium delivery system 224 is sanitizing system 225 , which may be located closer to a second end of enclosure 205 than a first end. Note that blasting medium delivery system 224 may also be described as being located upstream of sanitizing system 225 and by extension sanitizing system 225 is downstream from blasting medium delivery system 224 . Sanitizing system 225 includes a steam or hot air generator 231 , a steam or hot air conduit 233 , a steam or hot air rail 235 , and one or more hot air or steam pressure heads 227 . Steam or hot air generator 231 connects to pressure heads 227 by way of steam or hot air conduit 233 and steam or hot air rail 235 . At least one hot air or steam nozzle 229 extends from hot air or steam pressure heads 227 .
Rack transport system 226 includes a conveyor mechanism 208 .
Return system 228 includes a slide or guide portion 248 positioned below rack transport system 226 in an area below blasting medium delivery system 224 . Slide or guide portion 248 is located in a lower compartment 221 . Slide or guide portion 248 may have a vibratory mechanism (not shown) associated with it. Slide or guide portion 248 angles downwardly to mate with a funnel 203 . Funnel 203 may be associated with a blasting medium recovery storage system, which is similar to recovery storage system 30 of the first exemplary embodiment, or end portion 203 a of funnel 203 may be positioned within an opening 204 a of a hydrocyclone or cyclone separator unit 204 . Cyclone separator unit 204 contains a filtration system 219 near the output of the cyclone separator unit 204 . Cyclone separator unit 204 contains at least two outlets. A first outlet 206 is connected to a blasting medium storage system similar to storage system 18 described in the first exemplary embodiment. A second outlet 207 , which is for food residue and particles, connects to a collection system (not shown).
This system works as follows. An operator or user loads a carriage rack 104 through a first end 205 a of enclosure 205 and places carriage rack 104 on conveyor 208 . Conveyor 208 carries carriage rack 104 into enclosure 205 . As carriage rack 104 passes a plurality of pressure heads 201 , a blasting medium 100 , forced into the interior of enclosure 205 by a plurality of pressure nozzles 202 , impinges on carriage rack 104 and dishware 103 located within carriage rack 104 . The force and configuration of blasting medium 100 removes food debris, including grease and fatty acids, from dishware 103 . The speed of conveyor 208 , which is adjustable, determines the amount of time dishware spends in the area of pressure heads 201 . Conveyor 208 next moves carriage rack 104 into the area of hot air or steam pressure heads 227 . As a first step, steam may briefly emit from steam pressure heads 227 . The heat from this steam performs a sterilizing function for dishware 103 . Next, hot air may emit from hot air or steam pressure heads 227 to provide a drying function and to assist in sterilizing dishware 103 further. The total amount of time for the dishwashing process, from loading of a carriage rack 104 at first end 205 a of enclosure 205 to removal of carriage rack 104 at second end 205 b of enclosure 205 , is approximately five minutes, which is comparable to the total time for water-based dishwasher systems using a conveyor.
Automatic controls (not shown) may drive conveyor 208 . The automatic controls must insure smooth movement of each carriage rack 104 and its load of dishware 103 from the loading station through different portions of dishwasher system 200 until reaching unloading platform 120 . The automatic controls would include a motor start and stop, conveyor speed control, overload protection, emergency shutoff, and the ability of integrated sensors (e.g., magnetic, optical, etc., not shown) to detect the position of carriage rack 104 on conveyor 208 . Using sensors to detect the presence and location of a carriage rack 104 on conveyor 208 enables blasting medium delivery system 224 and sanitizing system 225 to operate only when a rack 104 is present rather than continuously operating, thus conserving resources.
A combination of blasting medium 100 and food debris, including grease and fatty acids, passes through openings 208 a in conveyor 208 and drops to slide or guide portion 248 . Slide or guide portion 248 is at an angle that encourages gravity to move blasting medium 100 and food debris to slide toward funnel 203 . Slide or guide portion 248 may include an electric or mechanical vibration mechanism (not shown) to enhance movement of food debris and blasting medium 100 toward funnel 203 . Slide or guide portion 248 may also include a nonstick coating to minimize sticking of food debris and blasting medium 100 on the surface of slide or guide portion 248 . Food debris and blasting medium 100 slides toward and enters funnel 203 , falling through opening 203 a of funnel 203 and entering opening 204 a of cyclone separator 204 . Cyclone separator 204 in combination with filtration system 219 separates blasting medium 100 from food debris. Blasting medium 100 , which is generally clean at this point, flows through first outlet 206 and returns to a recovery storage system, which may be similar to recovery storage system 30 . An additional apparatus may be placed between first outlet 206 and a recovery storage system to further clean and sterilize blasting medium 100 . Food debris or residue exits reclamation system 215 from second outlet 207 . This food debris or residue goes to a collection unit for disposal or incineration (not shown). To enhance the environmental friendliness of this configuration further, heat from incinerating the food debris, residue or waste may provide the energy used to create steam and hot air for sanitizing system 225 .
Conveyor 208 may be a straight-running conveyor belt system, as opposed to a side flexing conveyor system such as those manufactured by Intralox of Harahan, La. Several factors should be considered in choosing the appropriate material for the conveyor belt, which must be able to resist both heat and impact. Polypropylene, polyethylene, acetal, aluminum, stainless steel, carbon steel, and the like, as well as certain other plastics, are useable for a conveyor belt, but a preferred embodiment uses composite material(s) that resist heat and impact. Designing the conveyor also requires determining the best belt surface, link pitch, and drive method for the load of racks filled with kitchenware. The conveyor or belt must be of sufficient strength, taking into account the weight of dishware 103 and carriage racks 104 , the length of the conveyor, elevation changes, desired operating speed, maximum operating temperature, and service duty (i.e., start and stops). Square shafts transmit torque without the need for troublesome keys and keyways found on round shafts, provided the shaft material is strong enough to bear the load safely. A direct drive is preferred over positive drive systems that use drive shafts and sprockets, thus eliminating wear problems associated with friction rollers. Depending on belt tension and length, roller supports 209 , shown in FIG. 6 , may be used to help tension the belt and control or reduce catenary sag 223 a , shown in FIG. 5 , to catenary sag 223 b shown in FIG. 6 . Other materials or configurations may be acceptable, but the aforementioned are considered desirable.
The drive motor for the conveyor (not shown) is selected based on a number of factors. The drive motor horsepower requirement is calculated as follows:
MotorHorsepower = BeltDrivePower 100 % - Total % Losses × 100
where the % Losses are the mechanical efficiency losses due to such factors as gear reduction, ball bearings, and roller chains; and the Belt Drive Power is the power needed to overcome the resistance of moving the belt and the product. The type of motor has to compensate for such factors as rapid starting of the conveyor system. Soft starting electric motors or fluid couplings can help reduce adverse effects of such loadings.
In the first exemplary embodiment waterless dishwashing system for cleaning dishware items described above, the blasting dishwashing machine for cleaning dishware items can be assembled anywhere and constructed from off-the-shelf components, including a commercial air compressor, portable sandblasting units (nozzles, hoppers, and feed systems), clear acrylic sheeting, aluminum angle braces, hoses, fittings and nozzles, and fasteners. The items needed for the construction and operation of the system include the following: an air compressor (5 HP, 230 Volts); four portable blasting units (including hoppers, nozzles, and feed hoses or conduits); a pressure regulator; a pressure gauge; aluminum angle 1×1×⅛″×8′ (for guide rails); assorted fasteners; four acrylic sheets 24″×48″ and 0.375″ thick (for prototype enclosure); tubing, hoses, and connectors. This machine incorporates only four nozzles; three to direct the blasting agents at the dishware items with one nozzle to clear excess debris from the items. However, this system can include more nozzles since the construction is modular. As previously noted, enclosure 105 may be formed of poly(methyl methacrylate), also called PMMA or acrylic glass. The various conduits described may be in the form of tubing. Mounted to enclosure 105 are two rails 110 that support and guide carriage racks 104 which holds dishware 103 . A carriage rack 103 that holds dishware 103 passes through a blasting field similar those in current water jet systems. Because of the simplicity of this structure, this arrangement is suitable for temporary installation at a camp and suitable for mobility.
Several types of blasting media are appropriate for cleaning effectiveness, abrasiveness, and recyclability and may be used as blasting medium 100 . These include glass beads, including silicon or sand, and plastic beads of various sizes and hardness; e.g. plastic blasting media (20-40 U.S. Sieve); fine glass beads blasting media (100-170 U.S. Sieve); and coarse glass beads blasting media (50-70 U.S. Sieve).
Small plastic beads are safe in blasting delicate dishware without causing excessive wear, scratches on the surface of the dishware or causing nicks or chips at the edges. The blasting beads can also be recycled by cleaning them and re-introducing them into the blasting stream. However, chemicals are needed to clean the plastic beads. Glass beads offer exceptional cleaning capabilities and can be recovered and recycled to reduce the volume of secondary waste streams. The waste stream would consist of food particles and some blasting agent. However, both are environmentally safe, as the food is biodegradable and the glass/sand is environmentally neutral. Generally, silica-based material such as glass or other types of sand-based beads; e.g. clean natural fine sand, can be recycled without the aid of solvents or other chemicals. Since this material has a high melting point, it can be heated to incinerate and remove any contaminants as well as sterilize the medium, making it ready for reuse in blasting.
The contaminants that could be cleaned from dishware items and utensils include large food deposits, smaller food deposits, grease and films, stains, ketchup, mustard (fresh), mustard (dried), cottonseed oil, jelly, peanut butter, lipstick, and rice (soggy). Bacteria and microorganisms can be totally eliminated during sanitization by hot air or steam mist.
Dishware 103 may include plastic plates, bowls, trays, cups, and glasses; metal silverware; metal pots, pans, and utensils. Carriage racks 104 that hold the dishes and pass through the dishwasher are typical of large systems include marine ship dishwashers.
Blasting of dishware items is an effective cleaning method that virtually eliminates the gray water produced by the cleaning process. Glass beads, or silicon or sand, offer exceptional cleaning capabilities and can be recovered and recycled to reduce the volume of secondary waste streams. The waste stream consists of food particles and some blasting agent. However, both are environmentally safe, as the food is biodegradable and the glass or sand is environmentally neutral. This silicon (glass) blasting media may cause surface wear at high pressures, for example at 690.5 kPa (100 psi) and above. However, dishware would be cleaned without damage if the blasting system were operated at lower pressures. The process time increases for lower pressures, but remains within acceptable limits as compared to current dishwashing systems. Proper selection of fine sand particles/silica and adjustment of blasting pressure alleviates any concern about wear due to the hardness of the blasting agent.
Table I provides a rough comparison between operating parameters for a blasting dishwasher prototype and a typical water dishwasher system on board marine ships (such as the system manufactured by Insinger Machine Company). This water jet dishwasher system operates at 440 volts, 30 kW and 44.6 amperes and can clean a rack of dishes in approximately 5 minutes.
TABLE 1
Comparison
Water Jet
Blasting (prototype)
Voltage (volts)
440
230
Current (amperes)
44.6
35
Power (kW)
30
8
Cleaning Time/Rack (minutes)
5
3-5
Water Volume (liters)
189
0
Dry blasting dishwasher system 10 requires most of its power for the air compressor. The system runs at 230 volts, 35 amperes, and 8 kW. The time required to clean dishes is approximately 3 minutes. A complete cleaning cycle takes place in under 5 minutes, including removal of bulk food, blast cleaning, rinse and sterilization. The cycle times for current dishwashing systems range from 3 to 5 minutes to clean and sterilize a rack of dishes. Cleaning times of 2 to 3 minutes are achievable using the blasting method without excess abrasion. Thus, the cleaning time required for blasting is comparable to current systems.
In blasting dishwasher machines, the blasting material is recycled. Otherwise, a huge amount of material must be stored for extended operations. By using silica based blasting agents, such as sand or glass beads, the blasting medium can recycle through separation and high temperature incineration of the media. Recycling of the silica beads ensures that the system does not require large tanks for media storage. Any medium discarded along with removed food contaminants is environmentally safe, since it is the equivalent of sand, and can be safely dumped into seawater or used as a landfill with no adverse effects.
Recycling is rather important when the dishwasher is in the scullery of navy ships or on marine vessels to minimize the amount of blasting material needed for extended periods, since the storage of blasting material requires valuable onboard space. Recycling of used blasting material, either during or between actual cleaning cycles, is necessary to reduce the storage volume and decrease the secondary waste streams resulting from the cleaning process. Since the removal of food residuals from dirty dishware items does not alter the makeup or structure of the blasting agents, whether plastic or silica based, the blasting media can be reused without limitation. The amount of blasting media needed for the dishwasher will remain practically constant except from minor losses, which need to be replenished occasionally. The recycling process regenerates or refreshes the blasting agent supply by separation of food residue, particles, or contaminants that may stick to the beads. In the case of silica-based beads, high heat may be employed with the recycling process to ready the material for further use. For plastic-based media, a small amount of chemical cleaner or water may clean the plastic beads.
Recycling of medium 100 generally falls into two categories: 1) in-process recycling, or 2) external recycling.
For in process recycling of medium 100 , the recycling system receives used blasting medium 100 in addition to food residue from the cleaning process as the unit is cleaning dishware. The blasting agent is then treated and returned to the primary feed system for subsequent use. Benefits of this system include reduced material need and low operator intervention and hence it is usually the most desirable process. For external recycling, used blasting medium 100 is collected and recycled separately while the cleaning system is operating. This system reduces the complexity of the cleaning system itself, but requires larger quantities of blasting medium 100 since blasting medium 100 might not be recycled until a meal is finished. Waiting until a meal is complete may be acceptable since current cleaning systems are drained and cleaned between meals.
Separation options include technologies such as gravity separation, inertia separation, centrifugal or cyclone separation, screen filtration, and incineration.
Gravity separation is one of the simplest forms of separation, although it is somewhat inefficient because only materials with large differences in particle size and mass are separable. To be effective, the cross sectional area of the flow passageways must be large enough to provide sufficiently low velocities and the length must be great enough along to allow separation of the particles without the particles being carried by inertial forces. This separation technique may be a preliminary separator to capture the blasting beads and larger particles before further filtration or separation, assuming that the space requirements are not prohibitive.
Inertial separation typically employs baffles that deflect and redirect material based on mass and density of the particles. The baffle type of inertial separators can be designed to occupy less space than typical gravity separation systems, but care must be taken to ensure that the turbulence fields created by the baffles do not interfere with the separation process.
Screen separation and filtration is another means to separate various materials based on particle sizes. This technique could be used in conjunction with other methods to recycle the blast material. It is important to consider the maintenance and cleaning requirements for filtration, since contamination can rapidly foul the filter, rendering it useless.
One of the most promising technologies that can be used to separate the output stream is centrifugal or cyclone separation, wherein radial acceleration or centrifugal forces separate various materials. The centrifugal settling velocity, which is the outward or radial velocity of a particle in the separator, can be expressed by the following equation for particles within the Stokes' law range:
V c = α v K d 2 ( ρ - ρ 0 μ ) V t 2 R
Where V c =centrifugal settling velocity, V t =tangential velocity of the particle, and R=radius of the circular path of the particle. Types of centrifugal separators include high velocity cyclones, low velocity cyclones, and dynamic fan collectors.
Employing inertial separation means, such as cyclonic separation to remove the beads from contaminants, the beads separate from the bulk of the food debris. The beads are then subjected to high temperature heating elements for cleaning. If blasting medium 100 is a silica-blasting medium or other, similar type of blasting beads, the used medium can be heated to a temperature high enough to incinerate food particles. Off-the-shelf components or subsystems can be used to construct a separation and recycling unit. For example, abrasive separators used in the blasting field could be acquired and modified to work with the dishwashing system. Modifications or custom designs may be needed for integration with the other dishwashing components, taking into account the available space. These separators are typically based on a cyclonic design, such as the Cadillac brand abrasive separator available from Grainger industrial equipment supplies. The separator incorporates air volume control, variable negative pressures, and built-in filtration and collection in a durable polyethylene body.
In one embodiment of the present disclosure, steam jets are used as a final rinse cycle. The water required by the steam jets would be considerably less than for current water jet systems. In order to sterilize the dishes properly and to ensure that there is no residual blasting agent, a final stage employing heated air or steam jets or both in the cleaning cycle is added. The steam jets, directed at the dishware, remove any residual blasting agent from dishware surfaces. The combination of steam jets and heated air not only ensure thorough cleaning, but also serve to sterilize the dishware. Current dishwashing systems use two cycles, one cycle uses heated water and detergent and one cycle uses hotter rinse water to remove detergent and to sterilize the dishware. The goals of these two cycles are accomplished by dry blasting dishwasher system 10 with considerably lower water usage, since the only water used is by the steam jets, which is a considerably lower volume than used by water jets.
While various embodiments of the disclosure have been shown and described, it is understood that these embodiments are not limited thereto. The embodiments may be changed, modified and further applied by those skilled in the art. Therefore, these embodiments are not limited to the detail shown and described previously, but also include all such changes and modifications. | A dishwashing system for cleaning soiled kitchenware, dishware and utensils is provided. The dishwashing system uses a combination of compressed air and blasting media to thoroughly remove grease and loose as well as hardened food particles from soiled surfaces, without hand tool scrubbing, manual rinsing, or use of soap, detergent, surfactants or other chemicals, whether in pre-soaking or cleaning. This heavy-duty dishwashing system accomplishes this thorough cleaning using no or a minuscule quantity of water. The overall energy requirements are low compared to existing systems due to elimination of water, reduction of the heating load and possible use of the heat of incineration. The dishwashing system may include a system for reclaiming used blasting media by separation from food residues. The dishwashing system is most appropriate for locations where freshwater is unavailable or costly, such as arid zones and aboard ships, and where disposal of gray water is impermissible. | 0 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims the benefit of U.S. Provisional Patent Application Ser. No. 60/778,106, filed Mar. 2, 2006.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates generally to devices for holding and supporting various articles. More specifically, the present invention is a suspended rotary rack, with various embodiments including a specific bearing structure for supporting the underlying rack portion and also for allowing the rack to rotate as desired.
[0004] 2. Description of the Related Art
[0005] Innumerable racks and article holders have been developed in the past, ranging from simple shelves and platforms to more sophisticated devices with adjustable or movable shelves or other components. A subset of such devices comprises rotary racks and the like supported from the floor or other underlying surface. The well-known rotary clothes drying hanger for indoor use is among these devices.
[0006] One of the problems with such floor-supported devices is their relative lack of stability, particularly in the case of taller and narrower devices supported by a relatively narrow tripod or similar support structure. Such devices are easily knocked over, allowing breakable articles thereon to crash to the floor and incur damage, or at least be soiled by contact with the floor or underlying surface. Another problem with such devices is the amount of floor space they require. The requirement of a relatively small “footprint” area for the device and the need for stability are mutually exclusive, with relatively tall and narrow devices failing to provide the required stability and wider devices requiring too much floor space.
[0007] As a result, a number of suspended racks have been developed in the past. Such overhead supported devices solve the problems of the requirement of too much floor space and lack of stability. A few such devices have been developed which allow the rack to rotate or spin about a central suspended column, or to allow the column to rotate about a relatively stationary attachment. An example of such is found in Japanese Patent Publication No. 8-024,496 published on Jan. 30, 1996. According to the drawings and English abstract, this device is a motorized rotary clothes dryer, with a stationary overhead motor rotating a hanger shaft from which a series of hanger arms extend radially. The rotary hanger shaft has an eye at its upper end, through which a hook from the motor shaft is loosely installed. The assembly may be installed in the ceiling of an existing room, or within a floor supported rack or frame.
[0008] None of the above-mentioned patents or publications shows the present invention as claimed. Thus, a suspended rotary rack solving the aforementioned problems is desired.
SUMMARY OF THE INVENTION
[0009] The suspended rotary rack includes a pair of bearings in tandem within a rotating shaft, with a stationary fastener passing through the center of the upper or anchor bearing to engage the overlying structure. The inner race of the anchor bearing is relatively stationary, with the outer race rotating and being captured within and rotationally fixed relative to the rotary column or tube depending therefrom. An anchor block is affixed to the inner race of the anchor bearing, and thereby to the overlying support structure from which the device is suspended. The anchor block is somewhat smaller than the inside diameter of the depending tube, with the tube rotating around the stationary anchor block. The end of the anchor block opposite the anchor bearing contains a guide bearing of smaller diameter than the anchor bearing, with the outer race of the guide bearing being rotationally fixed within the stationary anchor block. The inner race of the guide bearing is secured to a guide block, with the guide block extending from the guide bearing to affix to the inner wall of the rotary tube or column and rotate therewith.
[0010] The above-described assembly not only provides free rotation of the rotary column or tube, but also assures that the tube will remain axially rigid due to the two tandem bearings of the assembly. The rotary bearing and column assembly is particularly well suited for the overhead support of a rotary clothes rack or the like, with the axial rigidity of the system assuring that the rack will not tip, tilt, or sway to any significant degree, regardless of any imbalance of the load placed thereon. Such a rotary clothes hanger may incorporate a folding arm mechanism to fold the arms parallel to the central rotary column when the device is not in use, thereby freeing up usable space around the central column. Other embodiments comprising other devices may be installed upon the above described rotary assembly, e.g., multiple arm or hook rotary hanger racks, single or multiple level rotary article holders, single or multiple level rotary platforms, i.e., “lazy Susans,” single or multiple level, multiple arm article holders, etc., as desired.
[0011] These and other features of the present invention will become readily apparent upon further review of the following specification and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 is an environmental, perspective view of a first embodiment of a suspended rotary rack according to the present invention, showing various features thereof.
[0013] FIG. 2 is an exploded perspective view of the central hub assembly and arms of the suspended rotary rack of FIG. 1 , showing further details thereof.
[0014] FIG. 3 is a partially broken away elevation view in section of the hub assembly of the rack of FIGS. 1 and 2 , showing further details thereof.
[0015] FIG. 4 is an exploded perspective view of the upper bearing assembly used in the various rack embodiments of the present invention, showing various details thereof.
[0016] FIG. 5 is an elevation view in section of the upper bearing assembly of the suspended rotary rack of the present invention, showing further details thereof.
[0017] FIG. 6 is a perspective view of a suspended rotary rack of the present invention configured as a multiple arm hanger.
[0018] FIG. 7 is a perspective view of a suspended rotary rack of the present invention configured as a multiple level article holder.
[0019] FIG. 8 is a perspective view of a suspended rotary rack of the present invention configured as a multiple level rotary tray.
[0020] FIG. 9 is a perspective view of a suspended rotary rack of the present invention configured as a multiple arm article holder.
[0021] Similar reference characters denote corresponding features consistently throughout the attached drawings.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0022] The present invention comprises various embodiments of a suspended rotary rack, in which the rack is anchored to an overhead structure (e.g., ceiling, etc.) and is free of contact with the underlying surface. The rack may have any of a large number of different configurations, including a rotary clothesline assembly with folding arms, article holding receptacles, hooks for holding clothing or other articles, etc., as desired. All of the various rotary rack embodiments utilize the same bearing assembly configuration, which allows the suspended rack support column and article holding elements extending therefrom to rotate freely while holding the assembly in an axially rigid relationship to the mounting structure in order to prevent swinging and swaying of the device.
[0023] FIG. 1 of the drawings provides a perspective view of a first embodiment of the present suspended rotary rack, comprising a rotary clothes-drying hanger 10 . The hanger 10 includes a rigid, hollow rotary rack support column 12 having an upper end 14 in which an axially rigid bearing assembly (shown in FIGS. 4 and 5 , and discussed further below) is installed, an opposite lower end 16 , and a medial portion 18 . An article support comprising a plurality of elongate folding arms 20 a , 20 b , 20 c , and 20 d extend radially from a hub 22 , with a series of flexible lines 24 a , 24 b , 24 c , and 24 d extending between each of the arms 20 a - 20 d and generally surrounding the hub 22 . While four arms and four flexible lines are shown in the example of FIG. 1 , it will be understood that more or fewer arms and lines may be provided, as desired.
[0024] FIGS. 2 and 3 illustrate the detailed structure of the hub 22 and its operation. The hub 22 is fixed within the lower end 16 of the rotating support column 12 (i.e., the hub 22 cannot rotate relative to the support column 12 but rotates in unison therewith) and includes a series of radially disposed arm attachment flange pairs 26 a , 26 b , 26 c , and 26 d extending therefrom. Each arm 20 a through 20 d includes a proximal end, respectively 28 a through 28 d , inserted between corresponding flange pairs 26 a through 26 d . A lateral pin 30 is installed through each flange attachment pair 26 a through 26 d and corresponding arm proximal end 28 a through 28 d , pivotally securing the arms to the hub 22 and defining a pivot axis for each arm. Each arm proximal end 28 a through 28 d further includes an arm extension locking flat, respectively 32 a through 32 d , disposed substantially parallel to the length of its corresponding arm, and a folding arm locking flat, respectively 34 a through 34 d , substantially normal to the plane of the corresponding extension locking flats and elongate axes of the arms 20 a - 20 d . While a series of four arms and corresponding attachment and pivot components is shown in FIGS. 1 and 2 and described above, it will be understood that any practicable number of three or more arms may be provided, as desired.
[0025] An arm position lock rod 36 passes concentrically through a passage in the hub 22 , with the rod 36 having a spring retainer end 38 (e.g., mating threaded nut 40 engaging the threaded end of the rod or bolt 36 ) disposed within the lower end 16 of the support column 12 , and an opposite external end 42 with a relatively large diameter, flat plate arm position lock 44 immovably affixed to the external end 42 of the rod 36 and disposed concentrically therewith. The arm position lock 44 preferably includes a handle 46 protruding therefrom to facilitate operating the device. An arm position lock spring 48 is compressively installed concentrically about the arm position lock rod 36 between the spring retainer end 38 thereof and the internal end of the hub 22 .
[0026] Operation of the above described folding arm mechanism is most clearly shown in FIG. 3 of the drawings. The arm position lock spring 48 is in compression and normally holds the lock rod 36 (and accordingly, the arm position lock 44 ) up against the lower end of the hub 22 and lower end 16 of the support column 12 in which the hub 22 is immovably affixed. When the lock 44 is in this position, the flat upper surface thereof bears against either the arm extension locking flats 32 a through 32 d or the folding arm locking flats 34 a through 34 d , depending upon whether the arms 20 a through 20 d are extended or folded, respectively. To fold the arms upwardly adjacent to the support column 12 , or to extend the folded arms to radiate from the hub 22 when they are folded, the arm position lock 44 is pulled away from the hub 22 and lower end 16 of the support column 12 . This provides a sufficient span between the lock 44 and hub 22 (and support column lower end 16 ) to provide clearance for the corners of the arms 20 a through 20 d , i.e., the intersections of the arm extension lock flats 32 a through 32 d and respective arm folding lock flats 34 a through 34 b , to pivot below the lower surface of the hub 22 (and support column lower end 16 ), thereby allowing the arms 20 a through 20 d to pivot from their extended position (shown in solid lines in FIG. 3 ) to their folded position (shown in broken lines in FIG. 3 ), or vice-versa.
[0027] When the arms have been positioned as desired, the tension on the arm position lock 44 is released, and the spring 48 pulls the lock 44 up against the appropriate lock flats of the proximal ends 28 a through 28 d of the arms 20 a through 20 d to hold the arms in the selected extended or folded position. While it is anticipated that the arms will be folded or extended in unison with one another, it will be seen that the arms pivot independently of one another, and need not be folded or extended collectively. One or more of the arms may be extended while the others remain folded, or one or more may be folded while the others remain extended, if so desired.
[0028] FIGS. 4 and 5 illustrate the structure of the axially rigid bearing assembly 50 , which is enclosed within the upper end 14 of the rotary rack support column 12 and which secures the support column 12 to the overlying structure (e.g., ceiling, etc.). A rotationally stationary anchor block 52 has a relatively small diameter upper or structure attachment end 54 , and an opposite relatively large diameter guide bearing housing end 56 with a guide bearing housing or receptacle 58 formed therein (shown in FIG. 5 ). The anchor block 52 has a concentric passage formed therethrough, through which a structure attachment fastener (e.g., a machine screw or bolt 60 , as shown in FIG. 4 , or a lag bolt or screw 62 , as shown in FIG. 5 , etc.) passes to attach column 12 to the overlying structure (e.g., ceiling plate P, as shown in FIG. 4 , or ceiling joist J, as shown in FIG. 5 , etc.). The assembly is spaced away from the overlying structure, as shown in FIG. 5 , in order to provide clearance to allow the outer rotary rack support column 12 to rotate, but the anchor block 52 and structure attachment fastener 60 or 62 are immovably affixed to the overlying structure and do not rotate or move relative thereto.
[0029] The structure attachment end 54 of the anchor block 52 has an anchor bearing 64 (e.g., ball bearing, as shown, or other type of bearing, such as a plain or tapered roller bearing, needle bearing, etc.) installed thereon, with the inner race 66 being immovably installed concentrically upon the anchor bearing installation and structure attachment end 54 of the anchor block 52 . The inner race 66 of the anchor bearing 64 is preferably a press fit over the bearing installation and structure attachment end 54 of the anchor block 52 to assure that the inner race 66 is axially rigid and rotationally stationary relative to the anchor block 52 . The outer race 68 is press fit or otherwise rotationally affixed and immovably secured in an axially rigid installation within the upper end 14 of the support column 12 . A set screw (not shown) or other additional locking means may be provided to secure the outer race 68 of the anchor bearing 64 within the upper end 14 of the support column 12 , as desired. While the inner race 66 of the anchor bearing 64 is immovably locked relative to the overlying structure, the outer race 68 , and therefore support column 12 , are free to rotate about the inner race 66 .
[0030] A relatively smaller diameter guide bearing 70 (e.g., ball bearing, as shown, or other type of bearing as desired) is installed concentrically within the guide bearing housing or receptacle 58 of the anchor block 52 , with the outer race 72 of the guide bearing 70 being immovably affixed in an axially rigid relationship with the anchor block 52 . The guide bearing 70 may be press fit within the anchor block 52 , and/or a conventional set screw (not shown) or other means may be used to provide further security for the guide bearing 70 . It will be seen that as the anchor block 52 does not rotate relative to the overlying structure, neither will the outer race 72 of the guide bearing 70 .
[0031] However, the inner race 74 of the guide bearing 70 is free to rotate relative to its outer race 72 , and is installed upon the relatively small diameter guide bearing end 76 of a guide block 78 . The inner race 74 of the guide bearing 70 is preferably a press fit onto the guide bearing end 76 of the guide block 78 , with the inner race 74 of the guide bearing 70 and the guide block 78 being rotationally locked to one another in an axially rigid relationship. The opposite rotary column engagement end 80 of the guide block 78 has a relatively larger diameter which fits tightly and immovably in an axially rigid concentric relationship within the inner diameter of the rotary rack support column 12 .
[0032] Further security for the guide bearing 70 installation to the guide block 78 is provided by a guide bearing and guide block assembly fastener 82 , which passes concentrically through the guide block 78 and inner race 74 of the guide bearing 70 . A relatively large diameter washer 84 a is installed beneath the head of the fastener 82 , in order to overlap and positively retain the inner race 74 of the guide bearing 70 on the guide bearing end 76 of the guide block 78 . A similar but somewhat larger diameter washer 84 b may be installed between the structure attachment end 54 of the anchor block 52 to overlap the inner race 66 of the anchor bearing 64 , and further to space the rotating outer race 68 and upper end 14 of the rotary rack support column 12 from the overlying structure.
[0033] In the above described structure, the anchor block 52 , inner race 66 of the anchor bearing 64 , and outer race 72 of the guide bearing 70 are all immovably affixed relative to the overlying structure. The outer race 68 of the anchor bearing 64 , inner race 74 of the guide bearing 70 and rotationally attached guide block 78 , and the upper end portion 14 and remainder of the rotary rack support column 12 , which is rotationally attached to the outer race 68 of the anchor bearing 64 and rotary column engagement end 80 of the guide block 78 , are free to rotate. As the anchor block 52 is relatively stationary and the overlying rotary rack support column 12 rotates therearound, the relatively larger diameter guide bearing end 56 of the anchor block 52 is made somewhat smaller than the inner diameter of the support column 12 , in order to provide a clearance gap 86 therebetween to preclude contact between the two components.
[0034] The above described axially rigid bearing assembly is not limited to use with the rotary clothes hanger rack 10 of FIG. 1 . It will be seen that a great variety of different suspended rotary rack configurations may be provided using the above-described bearing assembly, with the following embodiments being exemplary of but a few such devices.
[0035] FIG. 6 illustrates a suspended rotary rack 10 a in which a series of hooks 88 extend radially from the rotary support column 12 . The hooks 88 may be distributed both radially around the support column, and axially along the length of the support column, in any regular or irregular arrangement or configuration as desired. The support column 12 , along with its axially rigid bearing assembly (not shown in FIG. 7 ), is essentially identical to the support column 12 of FIG. 1 and bearing assembly 50 illustrated in FIGS. 4 and 5 .
[0036] FIG. 7 provides an illustration of another embodiment 10 b of a suspended rotary rack wherein a series of receptacle racks extend from the lower end 16 of a shortened rotary rack support column 12 . A series of support rods 90 extend downwardly and outwardly from the lower end 16 of the support column 12 , and turn vertically downward essentially parallel to the rotational axis of the support column 12 . A plurality of vertically spaced multiple receptacle racks 92 are installed within the area defined by the support rods 90 , with each rack 92 providing for the holding and containment of a plurality of articles (e.g., bottles, etc.) therein. The number of receptacles in each rack tier 92 is preferably equal to the number of support rods 90 , with each rack 92 being in the general form of a regular polygon with the support rods 90 connecting to their flat sides. In this manner, the receptacles themselves may be placed at the corners of the polygonal racks 92 , to facilitate placement and removal of articles to and from the racks 92 . A lower shelf 94 with accessory hooks 96 may also be provided at the base of the support rods 90 , if so desired.
[0037] FIG. 8 illustrates yet another embodiment 10 c of the present invention, wherein a plurality of circular trays 98 a and 98 b are installed upon the support column 12 to form a “lazy Susan” type device. At least one such tray is installed, or more than the two trays 98 a , 98 b shown in FIG. 8 may be installed, as desired. In the embodiment of FIG. 8 , a first or upper tray 98 a is installed along the medial portion 18 of the support column 12 , with a second or lower tray 98 b being installed at the lower end 16 of the column 12 . It will be seen that additional trays may be installed as desired and that the trays may have other than the circular shape shown in FIG. 8 . For example, an arcuate section may be removed from the circular shape, etc., as desired. It will further be seen that the rotary rack support column 12 may be extended to form two or more sections that rotate independently of one another by means of the installation of additional axially rigid bearing assemblies 50 as shown in FIGS. 4 and 5 . In this manner, two or more trays installed upon such an embodiment will be free to rotate independently of one another.
[0038] FIG. 9 illustrates still another embodiment of the suspended rotary rack, designated as 10 d , wherein a series of radially disposed arms 100 extend from the support column 12 . As in the case of the embodiment 10 a of FIG. 6 , the various arms may be distributed radially and/or axially in any even or uneven pattern along the length of the support column 12 , as desired. Each of the arms 100 terminates in a distal end 102 having an article support receptacle 104 extending therefrom, e.g., a ring or the like for holding a plant pot or similar article. The suspended rotary rack 10 d of FIG. 9 is particularly well suited for the storage and display of potted plants, but will be recognized as being useful for other purposes with little or no modification. It will also be noted that as in the case of the lazy Susan embodiment 10 c of FIG. 8 , the support column 12 may comprise several sections, each separated from the next by an axially rigid bearing assembly 50 with each arm 100 extending from a joint between adjacent sections of the column 12 . Alternatively, the arms 100 may be rotationally affixed to a single column 12 , or each to a separate segment of a multiple segment column, as desired.
[0039] In conclusion, the suspended rotary rack provides a rotating, suspended column that does not sway axially or transversely. The rack is particularly well suited for use as an indoor rotary clothes drying rack, with its folding arms providing further convenience when the device is not in use. However, the various other embodiments disclosed herein, as well as others falling within the scope of the present invention, are well suited for the storage and display of innumerable goods and articles in retail stores and other environments. Accordingly, the suspended rotary rack will prove to be a most desirable device to homeowners, as well as to those engaged in retail trades, and/or any other environment where such a suspended rotary rack may be useful.
[0040] It is to be understood that the present invention is not limited to the embodiments described above, but encompasses any and all embodiments within the scope of the following claims. | The suspended rotary rack may be configured as a rotary clothes hanger with folding arms, multiple arm or hook rotary hanger racks, and single or multiple level rotary article holders, rotary platforms, or multiple arm article holders. The rotary rack is suspended from an overhead support by a bearing assembly having two tandem bearings. The bearing assembly has an anchor block, an anchor bearing having an inner race attached to the upper end of the anchor block, and an outer race fixed within an upper end of a column. The outer race of a guide bearing is fixed within the lower end of the anchor block. The inner race of the guide bearing is fixed to a guide block, the guide block being fixed within the upper end of the column below the anchor bearing. The tandem bearing assembly precludes any radial or axial play of the column. | 3 |
BACKGROUND OF THE INVENTION AND PRIOR ART
Automated bone distraction apparatus is known but requires regular periodic adjustment by a skilled professional. As reported by Ilizarov in Clinical Orthopaedics and Related Research, No. 250, January 1990, the rate and frequency of bone distraction may have to be slowed, speeded up, or even reversed, depending upon the quality of bone formation in the distraction gap, the response of the soft tissues and nerves to elongation, and other considerations. If the distraction rate progresses too quickly, one of the first places it will be noticed is in the blood supply to the distal side of the break. If the blood supply is being compromised due to stretching the soft tissue too rapidly, the temperature of the tissue on the distal side of the break decreases. An additional symptom of hyper-distraction is lower oxygen concentration on the distal side of the distraction.
It is an object of the present invention to provide a bone distraction apparatus which incorporates a portable programmable controller and motor drive which may be carried at all times by the patient and which has appropriate built in safeguards to prevent tissue or bone damage due to distraction at improper rates or frequency of distractions,
SUMMARY OF THE INVENTION
The present invention provides a portable bone distraction apparatus comprising:
a) a motor driven bone distraction mechanism having at least two fasteners for attachment to the proximal and the distal sides of a bone break;
b) a motor for periodically moving said attachments relative to each other to distract the bone;
c) a microprocessor control circuit for controlling the operation of said motor;
d) input means for manually programming the desired rate of bone distraction into said microprocessor;
e) means for sensing a tissue condition parameter and for providing signals representative of the condition of tissue proximate the locations of said bone attachments to said microprocessor;
f) means for comparing said sensed condition signals with a normal condition parameter programmed into said microprocessor; and
g) means for adjusting the operation of said motor when said sensed condition signals vary by a predetermined amount from said normal condition parameter programmed into said microprocessor.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a schematic plan view of a portable bone distraction apparatus.
FIG. 2 is a sectional elevation taken at line 2--2 on FIG. 1.
FIG. 3 is a sectional elevation taken at line 3--3 on FIG. 1.
FIG. 4 is a schematic view of the microprocessor signal processing which controls the distraction apparatus of FIG. 1.
FIGS. 5A-5I show a preferred system algorithm and flow diagram.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The distraction apparatus comprises a frame 10 having a pair of telescopically moveable parts 12, 14 upon which bone attachment connectors such as pins or screws 16,18 are removeably mounted by conventional fasteners 20. The pins or screws are inserted through the skin and subcutaneous tissue directly into the bone segments (S1, S2) to be distracted on opposite sides of the break (B) which is shown to an enlarged scale for clarity.
The parts 12, 14 of the distraction frame are moved toward and away from each other at a controlled rate of speed and/or frequency of distraction by an electric motor 22. Motor 22 is rigidly affixed to part 12 and an internally threaded member 26 is rigidly affixed to part 14. Motor 22 through a gear reducer not shown, slowly rotates a rod 24 having a threaded end 25 which is received in the threaded member 26 such that the member 26 is axially positionable relative to the rod 24.
An alternative arrangement may employ a non-rotatable rod 24 which has a threaded portion engaged by a rotatable adaptor which is rotated by the motor 22 to axially position the rod relative to the motor, the end of the rod remote from the motor being secured to part 14 whereby part 14 can be positioned relative to part 12.
The relatively moveable parts 12, 14 of the distraction frame are telescopingly interengaged with close sliding tolerance and keyed to prevent relative rotation of part 12 relative to part 14 to maintain precise alignment of the parts and bone attachment pins or screws 16, 18 during distraction.
The motor 22 is preferably a D.C. motor having a reduction gearbox which is contained in a sealed housing which also contains a tach pulse generator 23 (FIG. 4) which generates electrical pulses indicative of the direction and number of rotations of the motor driveshaft, the number and duration of motor inactive intervals, and the number and duration of time intervals during which motor 22 is activated.
Referring now to FIG. 4, the tach pulses are fed from the motor 22 on line 30 to a counter IC8 and thence to a microprocessor databus 40 on line 30 and to latch IC7 on line 31 and thence to latch IC4. The distraction apparatus including the motor and control circuitry are all miniaturized and contained in a housing adapted to be carried by or worn by the patient. The housing also contains a replaceable source of electrical power in the form of a battery 41 whose output is suitably stepped down and delivered by an ON/OFF switch on line 42 to power the microprocessor and from relay K1 via power line 66 to drive the motor in forward or reverse directions as will be described below.
A pair of probes 50, 52 which sense the desired parameter such as temperature or oxygen content, is placed in the skin or subcutaneous tissue proximate the pins or screws 16, 18 on the proximal and distal sides of the bone break to sense tissue conditions at these locations. The probes 50, 52 each generate an electrical signal indicative of the condition sensed by the probes, the signals being transmitted with amplification at IC3 on lines 54, 56 to an analog/digital converter 60 and then to the microprocessor 40. The lowering of tissue temperatures proximate the distraction is a known precursor of possible tissue damage as is reduced oxygen content. The microprocessor compares the digitized sensor output signals with preprogrammed stored values representative of normal parameters expected at these locations. Programming of the microprocessor 40 is accomplished via a control panel 70 having a plurality of pushbuttons 70a-70e including YES, NO, UP ARROW, DOWN ARROW and CANCEL buttons for enabling the patient or the physician to easily select and increase or decrease the chosen parameter, the chosen data being transmitted to the microprocessor on line 71.
The microprocessor 40 is programmed to generate motor control signals on lines 62, 64, 66 and 68. The signals on line 62 comprise a motor power signal, a motor direction signal (FRW/REV) and a motor on safety signal. The signals are sent first to latch IC5, the motor power signal then being passed to transistor Q3 to control line 64 which provides a ground path for the motor 22. The motor FWD/REV signal is transmitted to transistor Q4 which controls line 66 through diode SD3 to either open or close the motor direction control relay K1 depending on which voltage polarity is needed. The motor safety relay signal is sent from latch IC5 to turn on transistor Q5 which provides a ground path for the motor through line 68 through diode SD4 by turning on safety relay K2. Relays K1 and K2 are connected to pass the FWD/REV and SAFETY control signals from microprocessor 40 to the motor 22 in accordance with soft tissue parameters sensed by sensors 50 and 52 which are compared in microprocessor 40 with the pre-programmed normal value. Upon deviation of the sensed soft tissue parameter beyond the programmed limit, the microprocessor first sends a direction control signal on lines 62, 63 and 66 which reverses the direction of rotation of motor 22 to immediately alleviate the condition and, if necessary, the microprocessor 40 sends a safety signal on lines 62, 65 and 68 to relay K2 to terminate delivery of the electrical power to the motor 22 to terminate distraction.
The control apparatus also includes an LCD screen 80 for selectively displaying various data such as the default distraction rate, e.g. 1 mm/24 hours; the programmed distraction rate; the programmed number of distraction events/hour; the programmed control parameter; the amount of distraction that took place during the last event; and the cumulative total distraction, all of which may be stored for analysis. Data is fed from microprocessor 40 to the LCD screen 80 on line 82 via latch IC4. Preferably the controller is programmed to provide an alarm signal which is intended to both audibly and visually (on the LCD) stimulate the patient to take corrective action or immediately consult his physician.
The microprocessor 40 permits corrective action by the patient himself by enabling him to program or adjust one or more of (1) the rate of continuous distraction, (2) the frequency of discrete time spaced distractions and (3) the duration of discrete time spaced distractions. For example, it may be desired to distract at the rate of 1.0 mm/day. Although conventional practice requires the patient to visit the physician or a technician for periodic adjustments of the distraction frame, it is known that a continuous steady rate of distraction is preferable or, since there is no known continuous automated distraction apparatus, the best approximation is to perform a series of incremental distractions. In general, the greater the number of small incremental distractions, the more benefit to the patient (as compared with fewer but greater incremental distractions) but also the more the patient is inconvenienced if he or she must visit a physician or technician each time. Accordingly the portable automated distraction apparatus disclosed herein is ordinarily programmed to provide continuous bone distraction at the highest tolerable rate of speed so long as sensed tissue parameters do not indicate possible soft tissue damage. Upon sensing excessive variations, the apparatus can be immediately reversed or automatically totally shut off, slowed down or the distraction can be performed incrementally with longer intervals between distractions to allow for sufficient tissue recovery. The possibilities for proper programming of the microprocessor are virtually boundless within the parameters set forth above. Preferably the system includes enough memory to store at least one week of distraction information and data which can be downloaded and transmitted by modem over telephone lines to a control center where the patient's physician or trained technicians can remotely make changes to the variables of the program.
Without limitation, the presently preferred embodiment uses an 80C32 microprocessor with 32 kilobytes of ROM memory and 32 kilobytes of RAM memory. Power may be input to the system from a battery eliminator 90 which may be used to power the system directly from a standard source of AC power, or to charge rechargeable batteries 41. FIGS. 5A-5I show the presently preferred script or system algorithm and a flow diagram thereof which uses tissue temperature as the sensed parameter.
Persons skilled in the art will readily appreciate that various modifications can be made from the preferred embodiment thus the scope of protection is intended to be defined only by the limitations of the appended claims. | A portable bone distraction apparatus comprises a frame having a pair of relatively moveable parts which are respectively connectable to the bone parts on opposite sides of a break and tissue condition sensors positionable on opposite sides of a break. The sensors determine tissue conditions such as temperature or oxygen content. The apparatus includes a microprocessor control circuit which governs rate and frequency of distractions with automatic termination or reduction of the rate and/or frequency of distraction if sensed conditions proximate the break exceed predetermined programmed values. | 0 |
BACKGROUND OF THE INVENTION
(4R-Cis)-1,1-dimethylethyl 6-(2-aminoethyl)-2,2-dimethyl-1,3-dioxan-4-acetate is a key intermediate in the preparation of (2R-trans)-5-(4-fluorophenyl)-2-(1-methylethyl)-N,4-diphenyl]-1-[2-(tetrahydro-4-hydroxy-6-oxo-2H-pyran-2-yl)ethyl]-1H-pyrrole-3-carboxamide or the salt of the hydroxy acid, [R-(R*,R*)]-2-(4-fluorophenyl)-β, δ-dihydroxy-5-(1-methylethyl)-3-phenyl-4-[(phenylamino)carbonyl]-1H-pyrrole-1-heptanoic acid calcium salt (2:1), corresponding to the opened lactone ring of the aforementioned compound described in U.S. Pat. Nos. 4,647,576 and 4,681,893, which are herein incorporated by reference. The aforementioned compound is useful as an inhibitor of the enzyme 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMG-CoA reductase) and is thus useful as a hypolipidemic and hypocholesterolemic agent.
(4R-Cis)-1,1-dimethylethyl 6-(2-aminoethyl)-2,2-dimethyl-1,3-dioxane-4-acetate may be, in turn, prepared from (4R-cis)-1,1-dimethylethyl 6-cyanomethyl-2,2-dimethyl-1,3-dioxane-4-acetate.
A synthetic procedure for preparing (4R-cis)-1,1-dimethylethyl 6-cyanomethyl-2,2-dimethyl-1,3-dioxane-4-acetate is disclosed in copending U.S. patent application Ser. No. 303,733. The aforementioned procedure involves a linear synthetic route involving 10 steps, including a low temperature (-85° C. to -95° C.) reaction carried out under carefully controlled conditions. The reaction involves reduction of a hydroxy ketone with sodium borohydride and a trialkylborane. Although this reaction provides the target compound in high enantiomeric excess, it is difficult to conduct on a large-scale and employs expensive reagents which are difficult to handle.
The displacement of sulfonates and halides by cyanide is well known in the art. However, such displacements in complex systems, and in particular a system containing a 1,3-dioxane ring, have not been successfully carried out. In point of fact, Sunay, U. and Fraser-Reid, B., Tetrahedron Letters, 27, pages 5335-5338 (1986) reported the failure of such a displacement in a system containing a 1,3-dioxane ring.
Thus, we have surprisingly and unexpectedly found that the nitrile of the present invention, (4R-cis)1,1-dimethylethyl-6-cyanomethyl-2,2-dimethyl-1,3-dioxane-4-acetate, can be obtained by a process of displacing various activated sulfonate or halide 1,3-dioxane derivatives with a metal cyanide.
The object of the present invention is an improved, short, efficient, and economical process for the preparation of (4R-cis)-1,1-dimethylethyl 6-cyanomethyl-2,2-dimethyl-1,3-dioxane-4-acetate. Thus, the present method avoids the costly, low temperature reaction of the prior method and is amenable to large scale synthesis.
SUMMARY OF THE INVENTION
Accordingly, a first aspect of the present invention is an improved process for the preparation of the compound of Formula I ##STR1## which comprises: (a) treating the compound of Formula IV ##STR2## with a compound of Formula V ##STR3## wherein Ar is aryl; and X is halogen in the presence of a base and solvent to afford a compound of Formula II ##STR4## wherein Ar is as defined above; or alternatively (b) treating a compound of Formula II with an alkali iodide in a solvent at about 20° C. to about the reflux temperature of the solvent to afford the compound of Formula III ##STR5## (c) treating a compound of Formula II or the compound of Formula III with a compound of Formula VI
M--CN VI
wherein M is an alkali metal, silver or copper (I) in a solvent at about 0° C. to about 100° C. to afford the compound of Formula I.
A second aspect of the present invention is a novel intermediate of Formula ##STR6## wherein L is halogen or ##STR7## wherein Ar is aryl, which is useful in the preparation of the compound of Formula I
DETAILED DESCRIPTION OF THE INVENTION
In this invention, the term "aryl" means an aromatic radical which is a phenyl group substituted by one to two substituents selected from halogen or nitro. "Halogen" is iodine, bromine, chlorine, and fluorine.
"Alkali metal" is a metal in Group IA of the periodic table and includes, for example, lithium, sodium, potassium, and the like.
The process of the present invention is a new, improved, economical, and commercially feasible method for preparing (4R-cis)-1,1-dimethylethyl 6-cyanomethyl-2,2-dimethyl-1,3-dioxane-4-acetate. The process of the present invention is outlined in the following scheme: ##STR8##
A compound of Formula II wherein Ar is aryl is prepared by treating the compound of Formula IV with a compound of Formula V ##STR9## wherein X is a halogen such as, for example, chlorine, bromine, iodine, fluorine, and the like, and Ar is as defined above in the presence of a base such as, for example, triethylamine, diiospropylethylamine, 4-dimethylaminopyridine and the like, and a solvent such as, for example, pyridine, toluene, methylene chloride, and the like at about 0° C. to about 40° C. to afford a compound of Formula II. Preferably the reaction is carried out in the presence of triethylamine in methylene chloride at about 0° C. to about 25° C.
The compound of Formula III is prepared by treating a compound of Formula II with an alkali iodide such as, for example, sodium iodide, potassium iodide, and the like in a solvent such as, for example, acetone, 2-butanone, and the like, at about 0° C. to about the reflux temperature of the solvent to afford the compound of Formula III. Preferably the reaction is carried out with sodium iodide in 2-butanone at about 55° C.
The compound of Formula I is prepared by treating either a compound of Formula II, or a compound of Formula III with a compound of Formula VI
M--CN VI
wherein M is an alkali metal, such as, for example, lithium, sodium, potassium and the like, silver or copper (I) (cuprous) optionally in the presence of a quaternary ammonium salt such as, for example, tetrabutylammonium bromide, tetrabutylammonium iodide, benzyltriethylammonium chloride and the like in a solvent such as, for example, ethanol, dimethyl sulfoxide, dimethylformamide, dimethylpropyleneurea, dimethylethyleneurea, tetramethylurea, N-methylpyrrolidinone, tetrahydrofuran, toluene, methylene chloride, and the like, mixtures thereof, as well as any of the aforementioned water-immiscible solvents in combination with water, that is, in a phase transfer procedure using the quaternary ammonium salts as described above at about 0° C. to about the reflux temperature of the solvent to afford a compound of Formula I. Preferably the reaction is carried out in dimethyl sulfoxide at about 20° C. to about 50° C.
The compound of Formula IV is disclosed in European Patent Application No. 0 319 847. Compounds of Formula V and Formula VI are either known or capable of being prepared by methods known in the art.
Copending U.S. patent application Ser. No. 30,733 discloses the use of (4R-cis)-1,1-dimethylethyl 6-cyanomethyl-2,2-dimethyl-1,3-dioxane-4-acetate in the preparation of (4R-cis)-1,1-dimethylethyl 6-(2-aminoethyl)-2,2-dimethyl-1,3-dioxane-4-acetate which in turn is used to prepare (2R-trans)-5-(4-fluorophenyl)-2-(1-methylethyl)-N,4-diphenyl-1-[2-(tetrahydro-4-hydroxy-6-oxo-2H-pyran-2-yl) ethyl]-1H-pyrrole-3-carboxamide or the salt of the hydroxy acid, [R-(R*,R*)]-2-(4-fluorophenyl)-β,δ-dihydroxy-5-(1-methylethyl)-3-phenyl-4-[(phenylamino)carbonyl[-1H-pyrrole-1-heptanoic acid calcium salt (2:1), corresponding to the opened lactone ring of the aforementioned compound which is disclosed in U.S. Pat. Nos. 4,647,576 and 4,681,893 as a useful hypolipidemic and hypocholesterolemic agent.
The following examples are illustrative to show the present process, the preparation of starting materials, and the use of (4R-cis)-1,1-dimethylethyl 6-cyanomethyl-2,2-dimethyl-1,3-dioxane-4-acetate obtained by the present process to prepare the key intermediate, (4R-cis)-1,1-dimethylethyl 6-(2-aminoethyl)-2,2-dimethyl-1,3-dioxane-4-acetate, in the synthesis of (2R-trans)-5-(4-fluorophenyl)-2-(1-methylethyl)-N,4-diphenyl-1-[2-(tetrahydro-4-hydroxy-6-oxo-2H-pyran-2-yl)ethyl]-1H-pyrrole-3-carboxamide or the salt of the hydroxy acid, [R-(R*,R*)]-2-(4fluorophenyl)-β,δ-dihydroxy-5-(1-methylethyl)-3-phenyl-4-[(phenylamino)carbonyl]-1H-pyrrole-1-heptanoic acid calcium salt (2:1), corresponding to the opened lactone ring of the aforementioned compound useful as a hypolipidemic and hypocholesterolemic agent.
EXAMPLE 1
(4R-cis)-1,1-Dimethylethyl 6-cyanomethyl-2,2-dimethyl-1,3-dioxane-4-acetate
Method A
Step A: Preparation of (4R-cis)-1,1-dimethylethyl 6-(4bromobenzene)sulfonyloxy-2,2-dimethyl-1,3-dioxane-4-acetate
To a stirring, 20°-25° C. solution of the (4R-cis)-1,1-dimethylethyl 6-hydroxymethyl-2,2-dimethyl-1,3-dioxane-4-acetate (European Patent Application 0319,847) (10 g, 38 mmol) in methylene chloride) (250 mL) containing triethylamine (10 mL, 72 mmol) is added 4-bromobenzenesulfonyl chloride (15 g, 57.5 mmol). Stirring is continued at 20°-25° C. for 20 hours, the solution is poured onto 250 mL of water and the layers separated. The upper aqueous layer is extracted with 250 mL of methylene chloride and the combined organic layers are washed with 200 mL each of saturated sodium bicarbonate solution, to ensure complete removal of 4-bromobenzenesulfonyl chloride and then saturated sodium chloride solution. Drying the solution with magnesium sulfate and concentration in vacuo gives 26.3 g of the product as a light orange solid.
Step B: Preparation of (4R-cis)-1,1-dimethylethyl 6-cyanomethyl-2,2-dimethyl-1,3-dioxane-4-acetate
To a stirring 20°-25° C. solution of the crude 4-bromobenzenesulfonate (24.2 g, 36 mmol) in dimethyl sulfoxide (100 mL) is added sodium cyanide (4.0 g, 81 mmol). The mixture is stirred at 20°-25° C. for 42 hours, a further 2 g (40.5 mmol) of sodium cyanide is added, and stirring continued at 20°-25° C. for 96 hours. The mixture is poured onto 200 mL of water and extracted with 2×200 mL of ethyl acetate. The combined extracts are washed with 100 mL each saturated sodium bicarbonate solution, saturated sodium chloride solution, dried (magnesium sulfate), and concentrated in vacuo to give the product, 11.3 g as a red-brown oil, which solidifies on standing. Column chromatography on flash silica gel and eluting with hexane/ethyl acetate (4:1) gives the product 9.5 g, as pale yellow needles; mp 67.2°-69.7° C. Vapor phase chromatography (VPC): 30 meter DB-5 capillary column 40° to 280° C. at 15° C./min. 18.63 min., 98.35% (area).
Nuclear magnetic resonance ( 1 H-NMR): (CDCl 3 ) Υ1.38 (3H, s), 1.45 (9H, s), 1.75 (1H, m), 2.39 (2H, dq), 2.51 (2H, d), 4.10-4.32 (2H, m). Optical Rotation: [α] D 1.33° (C=1, CHCl 3 ).
Method B
Step A: Preparation of (4R-cis)-1,1-dimethylethyl 6-(4-chlorobenzene)sulfonyloxy-2,2-dimethyl-1,3-dioxane-4-acetate
To a stirring, 0°-5° C. solution of the (4R-cis)-1,1-dimethylethyl 6-hydroxymethyl-2,2-dimethyl-1,3-dioxane-4-acetate (European Patent Application 0319,847) (10 g, 38 mmol) in methylene chloride (250 mL) containing triethylamine (10 mL, 72 mmol) is added 4-chlorobenzenesulfonyl chloride (12.7 g, 60 mmol). Stirring is continued at 0°-5° C. for 2.5 hours and the solution slowly warmed to 20°-25° C. over a period of 2 hours. The solution is poured onto 200 mL of water and the layers separated. The upper aqueous layer is extracted with 200 mL of methylene chloride and the combined organic layers are washed with 200 mL each of saturated sodium bicarbonate solution to ensure complete removal of 4-chlorobenzenesulfonyl chloride and then saturated sodium chloride solution. Drying the solution with magnesium sulfate and concentration in vacuo gives 21.5 g of the product as a pale yellow solid.
Step B: Preparation of (4R-cis)-1,1-dimethylethyl 6-cyanomethyl-2,2-dimethyl-1,3-dioxane-4-acetate
To a stirring 20°-25° C. solution of the crude 4-chlorobenzenesulfonate (21.5 g, 38 mmol) in dimethyl sulfoxide (100 mL) is added sodium cyanide (4.0 g, 81 mmol). The mixture is stirred at 20°-25° C. for 40 hours, a further 2 g (40.5 mmol) of sodium cyanide is added and stirring continued at 20°-25° C. for 4.5 hours and 48°-52° C. for 24 hours. The mixture is poured onto 200 mL of water and extracted with 2×250 mL of ethyl acetate. The combined extracts are washed with 100 mL each saturated sodium bicarbonate solution, saturated sodium chloride solution, dried (magnesium sulfate), and concentrated in vacuo to give the product, 11.7 g as a yellow-orange solid. The product is 90% pure (by VPC).
Method C
Step A: Preparation of (4R-cis)-1,1-dimethylethyl 6-(2,5-dichlorobenzene)sulfonyloxy-2,2-dimethyl-1,3-dioxane-4-acetate
To a stirring 0°-5° C. solution of the (4R-cis)-1,1-dimethylethyl 6-hydroxymethyl-2,2-dimethyl-1,3-dioxane-4-acetate (European Patent Application 0319,847) (10 g, 38 mmol) in methylene chloride (250 mL) containing triethylamine (10 mL, 72 mmol) is added 2,5-dichlorobenzenesulfonyl chloride (14.7 g, 57.5 mmol). Stirring is continued at 0°-5° C. for 3.5 hours, the solution is poured onto 200 mL of water, and the layers separated. The upper aqueous layer is extracted with 200 mL of methylene chloride and the combined organic layers are washed with 200 mL each of saturated sodium bicarbonate solution to ensure complete removal of 2,5-dichlorobenzenesulfonyl chloride and then saturated sodium chloride solution. Drying the solution with magnesium sulfate and concentration in vacuo gives 24.6 g of the product as a yellow-orange oil.
Step B: Preparation of (4R-cis)-1,1-dimethylethyl 6-cyanomethyl-2,2-dimethyl-1,3-dioxane-4-acetate
To a stirring 20°-25° C. solution of the crude 2,5-dichlorobenzenesulfonate (24.6 g, 38 mmol) in dimethyl sulfoxide (100 mL) is added sodium cyanide (4.0 g, 81 mmol). The mixture is stirred at 20°-25° C. for 44 hours, a further 1 g (20 mmol) of sodium cyanide is added and stirring continued at 20°-25° C. for 24 hours. The mixture is poured onto 200 mL of water and extracted with 2×250 mL of ethyl acetate. The combined extracts are washed with 100 mL each saturated sodium bicarbonate solution, saturated sodium chloride solution, dried (magnesium sulfate), and concentrated in vacuo to give the product, 10.7 g as a brown oil, which solidifies on standing. The material is 85% pure (by VPC).
Method D
Step A: Preparation of (4R-cis)-1,1-dimethylethyl 6-(2-nitrobenzene)sulfonyloxy-2,2-dimethyl-1,3-dioxane-4-acetate
To a stirring 20°-25° C. solution of the (4R-cis)-1,1-dimethylethyl 6-hydroxymethyl-2,2-dimethyl-1,3-dioxane-4-acetate (European Patent Application 0319,847) (10 g, 0.038 mol) in methylene chloride (250 mL) containing triethylamine (7 mL, 0.05 mol) is added 2-nitrobenzenesulfonyl chloride (9.8 g, 0.043 mol). Stirring is continued at 20°-25° C. for 24 hours, a further portion of 2-nitrobenzenesulfonyl chloride (2.0 g, 0.009 mol) is added and the solution stirred for a further 4 hours. The solution is then poured onto 200 mL of water and the layers separated. The upper aqueous layer is extracted with 250 mL of methylene chloride and the combined organic layers are washed with 100 mL each of saturated sodium bicarbonate solution to ensure complete removal of 2-nitrobenzenesulfonyl chloride and then saturated sodium chloride. Drying the solution with magnesium sulfate and concentration in vacuo gives 20.8 g of the product as a green oil.
Step B: Preparation of (4R-cis)-1,1-dimethylethyl 6cyanomethyl-2,2-dimethyl-1,3-dioxane-4-acetate
To a stirring 20°-25° C. solution of the crude 2-nitrobenzenesulfonate (19 g, 35.8 mmol) in dimethyl sulfoxide (100 mL) is added sodium cyanide (4.0 g, 81 mmol). The mixture is stirred at 20°-25° C. for 17 hours, poured onto 200 mL of water, and extracted with 2×200 mL of ethyl acetate. The combined extracts are washed with saturated sodium bicarbonate solution, saturated sodium chloride solution, dried (magnesium sulfate), and concentrated in vacuo to give the product, 10.8 g as a red-brown oil. Column chromatography on flash silica eluting with hexane/ethyl acetate (4:1) gives the product 8.1 g, as a yellow oil which solidifies on standing. The product is 97.4% pure (by VPC).
Method E
Step A: Preparation of (4R-cis)-1,1-dimethylethyl 6-(4-nitrobenzene)sulfonyloxy-2,2-dimethyl-1,3-dioxane-4-acetate
To a stirring 20°-25° C. solution of the (4R-cis)-1,1-dimethylethyl 6-hydroxymethyl-2,2-dimethyl-1,3- dioxane-4-acetate (European Patent Application 0319,847) (10 g, 0.038 mol) in methylene chloride (250 mL) containing triethylamine (7 mL, 0.05 mol) is added 4-nitrobenzenesulfonyl chloride (10.5 g, 43 mmol). Stirring is continued at 20°-25° C. for 22 hours, the solution is poured onto 200 mL of water and the layers separated. The upper aqueous layer is extracted with 250 mL of methylene chloride and the combined organic layers are washed with 100 mL each of saturated sodium bicarbonate solution to ensure complete removal of 4-nitrobenzenesulfonyl chloride and then saturated sodium chloride solution. Drying the solution with magnesium sulfate and concentration in vacuo gives 18.7 g of the product as a brown oil which solidifies immediately.
Step B: Preparation of (4R-cis)-1,1-dimethylethyl 6-cyanomethyl-2,2-dimethyl-1,3-dioxane-4-acetate
To a stirring 40°-45° C. solution of the crude 4-nitrobenzenesulfonate (12.7 g, 28.5 mmol) in dimethyl sulfoxide (100 mL) is added sodium cyanide (4.0 g, 81 mmol). The mixture is stirred at 40°-45° C. for 1 hour, poured onto 200 mL of water and extracted with 2×200 mL of ethyl acetate. The combined extracts are washed with 100 mL each saturated sodium bicarbonate solution, saturated sodium chloride solution, dried (magnesium sulfate), and concentrated in vacuo to give the product, 8 g as a red-brown oil. Column chromatography on flash silica eluting with hexane/ethyl acetate (4:1) gives the product 2.8 g as a yellow oil which solidifies on standing. The product is 98.0% pure (by VPC).
Method F
Step A: Preparation of (4R-cis)-1,1-dimethylethyl 6-(4-chlorobenzene)sulfonyloxy-2,2-dimethyl-1,3-dioxane-4acetate
To a stirring, 0°-5° C. solution of the (4R-cis)-1,1-dimethylethyl 6-hydroxymethyl-2,2-dimethyl-1,3-dioxane-4-acetate (European Patent Application 0319,847) (10 g, 38 mmol) in methylene chloride (250 mL) containing triethylamine (10 mL, 72 mmol) is added 4-chlorobenzenesulfonyl chloride (12.7 g, 60 mmol). Stirring is continued at 0°-5° C. for 2.5 hours and the solution slowly warned to 20°-25° C. over a period of 2 hours. The solution is poured onto 200 mL of water and the layers separated. The upper aqueous layer is extracted with 200 mL of methylene chloride and the combined organic layers are washed with 200 mL each of saturated sodium bicarbonate solution to ensure complete removal of 4-chlorobenzenesulfonyl chloride and then saturated sodium chloride solution. Drying the solution with magnesium sulfate and concentration in vacuo gives 21.5 g of the product as a pale yellow solid.
Step B: Preparation of (4R-cis)-1,1-dimethylethyl 6-iodomethyl-2,2-dimethyl-1,3-dioxane-4-acetate
To a stirring, 55° to 60° C. suspension of the (4R-cis)-1,1-dimethylethyl 6-(4-chlorobenzene)sulfonyloxy-2,2-dimethyl-1,3dioxane-4-acetate (21.5 g, 38 mmol) in 2-butanone (100 mL) containing potassium carbonate (10 g, 77 mmol) is added sodium iodide (11.4 g, 77 mmol). Stirring is continued at 55° C. for 30 minutes. The mixture is then heated to a gentle reflux for 18 hours, the solids removed by filtration and the filtrate concentrated to give the product 14 g as an oil.
Step C: Preparation of (4R-cis)-1,1-dimethylethyl 6-cyanomethyl-2,2-dimethyl-1,3-dioxane-4-acetate
To a stirring 20° to 25° C. solution of the crude iodide (14 g, 38 mmol) in dimethyl sulfoxide (150 mL) is added sodium cyanide (3.8 g, 77 mmol). The mixture is stirred at 20° to 25° C. for 5 days, poured onto 300 mL water and extracted with 2×250 mL of ethyl acetate. The combined extracts are washed with saturated sodium bicarbonate solution, saturated sodium chloride solution, dried (magnesium sulfate), and concentrated in vacuo to give the product, 10 g as a pale-yellow oil which solidifies on standing. The product is 82.4% pure (by VPC).
EXAMPLE 2
(4R-cis)-1,1-dimethylethyl 6-(2-aminoethyl)-2,2-dimethyl-1,3-dioxane-4-acetate
A solution of (4R-cis)-1,1-dimethylethyl 6-cyanomethyl-2,2-dimethyl-1,3-dioxane-4-acetate, (Example 1) 5.63 g (0.048 mol), in 100 mL of methanol saturated with gaseous ammonia is treated with 0.5 g of Raney nickel 190 30 and hydrogen gas in a shaker at 50 pounds per square inch (psi) and 40° C. After 16 hours, thin layer chromatography indicates no starting nitrile present. The suspension is cooled, filtered through filter aid, and concentrated to an oil. This crude oil is purified by flash chromatography on silica gel with 30:20:1 (ethyl acetate:methanol:ammonium hydroxide) as eluant to give 4.93 g of (4R-cis)-1,1-dimethylethyl 6-(2-aminoethyl)- 2,2-dimethyl-1,3-dioxane-4-acetate (98.2 area %) as a clear oil.
200 MHz 1 H-NMR (CDCl 3 ) 1.0-1.2 (m, 1H), 1,22 (s, 3H), 1.31 (s, 12H), 1.35-1.45 (m, 3H), 2.15 (dd, 1H, J=15.1 Hz, J=6.2 Hz), 2.29 (dd, 1H, J=15.1 Hz, J =7.0 Hz), 2.66 (t, 2H, J=6.6 Hz), 3.82 (m, 1H), 4.12 (m, 1H).
13 C-NMR (CDCl 3 , 50 MHz) δ19.60, 27.96, 30.00, 36.50, 38.25, 39.79, 42.61, 66.08, 67.18, 80.21, 98.35, 169.82.
GC/MS m/e 202, 200, 173, 158, 142, 140, 114, 113, 100, 99, 97, 72, 57.
FTIR (neat) 951.6, 1159.9, 1201.1, 1260.3, 1314.3, 1368.3, 1381.2, 1731.0, 2870.3, 2939.8, 2980.9, 3382.2 cm -1 .
EXAMPLE 3
(±) 4-Fluoro-α-[2-methyl-1-oxopropyl]-γ-oxo-N,β-diphenylbenzenebutaneamide mixture of [R-(R*,R*)], [R-(R*,S*)], {S-(R*,R*)] and [S-(R8,S*)] isomers
Step A: Preparation of 4-Methyl-3-oxo-N-phenyl-2(phenylmethylene)pentanamide
A suspension of 100 kg of 4-methyl-3-oxo-N-phenylpentanamide (Example A) in 660 kg of hexanes is treated with agitation under nitrogen with 8 kg of β-alanine, 47 kg of benzaldehyde, and 13 kg of glacial acetic acid. The resulting suspension is heated to reflux with removal of water for 20 hours. An additional 396 kg of hexanes and 3 kg of glacial acetic acid is added and reflux continued with water removal for 1 hour. The reaction mixture is cooled to 20° to 25° C., and the product is isolated by filtration. The product is purified by slurrying in hexanes at 50°-60° C., cooling, and filtration. The product is slurried twice with water at 20° to 25° C., filtered, and dried in vacuo to yield 100 kg of 4-methyl-3-oxo-N-phenyl-2-(phenylmethylene)pentanamide, mp 143.7°-154.4° C.
Vapor Phase Chromatography (VPC): 30 meter DB-5 capillary column 50° to 270° C. at 15° C./min. 19.33 min., 99.7% (area).
Gas Chromatography/Mass Spectrometry (GC/MC): M/Z 293 [M] + .
Nuclear Magnetic Resonance ( 1 H-NMR): (CDCl 3 ) δ1.16 (6H, d), 3.30 (1H, quin.), 7.09 (1H, m), 7.28 (5H, m), 7.49 (5H, m), 8.01 (1H, brs).
Step B: Preparation of (±) 4-Fluoro-α-[2-methyl-1-oxopropyl]-γ-oxo-N-β-diphenylbenzenebutaneamide mixture of [R-(R*,R*)], [R-(R*,S*)], [S-(R*,R*)] and [S-(R*,S*)]isomers
A solution of 17.5 kg of 3-ethyl-5-(2-hydroxyethyl)-4-methylthiazolium bromide in 300 L of anhydrous ethanol is concentrated by distillation of 275 L of the ethanol. Under an argon atmosphere, 100 kg (340 mol) of 4-methyl-3-oxo-N-phenyl-2-(phenylmethylene)pentamide, 47.5 L (340 mol) of triethylamine, and 40 L (375 mol) of 4-fluorobenzaldehyde are added. The resulting solution is stirred and heated at 75° to 80° C. for 23 hours. The product begins to form as solid after approximately 1.5 hours but approximately 24 hours is required for essentially complete conversion. The slurry is dissolved in 600 L of isopropanol at 80° C. The resulting solution is slowly cooled and the (±) 4-fluoro-α-[2-methyl-1-oxopropyl]-γ-oxo-N,β-diphenyl-benzenebutaneamide mixture of [R-(R*,R*)], [R-(R*,S*)], [S-(R*,R*)] and [S-(R*,S*)] isomers isolated by filtration. Washing the precipitate with isopropanol and drying in vacuo yielded 99 kg of (±) 4-fluoro-α-[2-methyl-1-oxopropyl]-γ-oxo-N,β-diphenylbenzenebutanamide mixture of [R-(R*,R*)], [R-(R*,S*)], [S-(R*,R*)], and [S-(R*,S*)] isomers; mp 206.8°-207.6° C.
1 H-NMR: (CDCl 3 ) δ1.03 (3H, d), 1.22 (3H, d), 2.98 (1H, quin.), 4.91 (1H, d, J=11 Hz). 5.51 (1H, d, J=11 Hz), 6.98-7.43 (12H, m), 8.17 (2H, dd), 9.41 (1H, brs).
High Pressure Liquid Chromatography (HPLC): (Acetonitrile:tetrahydrofuran:water) (40:25:55) Econosil C 18 5.sub.μ 25 cm 1.0 mL/min 254 nm 16.77 min 99.2% (area).
EXAMPLE 4
(2R-Trans)-5-(4-fluorophenyl)-2-(1-methylethyl)-N,4-diphenyl-1-[2-(tetrahydro-4-hydroxy-6-oxo-2H-pyran-2-yl)ethyl]-1H-pyrrole-3-carboxamide
Method A
Step A: Preparation of (4R-cis)-1,1-dimethylethyl 6-[2[2-(4-fluorophenyl)-5-(1methylethyl)-3-phenyl-4-[(phenylamino)carbonyl]-1H-pyrrol-1-yl]ethyl]-2,2-dimethyl-1,3-dioxane-4-acetate
A solution of (4R-cis)-1,1dimethylethyl 6-(2-aminoethyl)-2,2-dimethyl-1,3-dioxane-4-acetate, (Example 2) 1.36 g (4.97 mmol), and (±)-4-fluoro-α-[2-methyl-1-oxopropyl]-γ-oxo-N,β-diphenylbenzenebutaneamide mixture of [R-(R*,R*)], [R-(R*,S*)], [S-(R*,R*)], and [S-R*,R*)] isomers, (Example 3) 1.60 g (3.83 mmol), in 50 mL of heptane:toluene (9:1) is heated at reflux for 24 hours. The solution is cooled slightly and 15 mL of 2-propanol added. The mixture is allowed to cool to 25° C. and filtered to give 1.86 g of (4R-cis)-1,1-dimethylethyl 6-[2[2-(4fluorophenyl)-5-(1-methylethyl)-3-phenyl-4-[(phenylamino)carbonyl]-1H-pyrrol-1-yl] ethyl]-2,2-dimethyl-1,3-dioxane-4-acetate as a yellow solid.
1 H-NMR (CDCl 3 , 200 MHz) δ1-1.7 (m, 5H), 1.30 (s, 3H), 1.36 (s, 3H), 1.43 (s, 9H), 1.53 (d, 6H, J=7.1 Hz), 2.23 (dd, 1H, J=15.3 Hz, J=6.3 Hz), 2.39 (dd, 1H, J=15.3 Hz, J=6.3 Hz), 3.5-3.9 (m, 3H), 4.0-4.2 (m, 2H), 6.8-7.3 (m, 14H).
13 C-NMR (CDCl 3 , 50 MHz) δ19.69, 21.60, 21.74, 26.12, 27.04, 28.12, 29.95, 36.05, 38.10, 40.89, 42.54, 65.92, 66.46, 80.59, 98.61, 115.00, 115.34, 115.42, 11952, 121.78, 123.36, 126.44, 128.21, 128.31, 128.52, 128.75, 130.43, 133.01, 133.17, 134.69, 138.38, 141.47, 159.72, 164.64, 169.96.
Step B: Preparation of (2R-trans)-5(4-fluorophenyl)-2-(2-methylethyl)-N,4-diphenyl-1-[2-(tetrahydro-4-hydroxy-6-oxo-2H-pyran-2-yl)ethyl]-1H-pyrrole-3-carboxamide
(4R-cis)-1,1-dimethylethyl 6-[2[2-(4-fluorophenyl)-5-(1-methylethyl)-3-phenyl-4[(phenylamino)carbonyl]-1H-pyrrol-1-yl]ethyl]2,2-dimethyl-1,3-dioxane-4-acetate, 4.37 g (6.68 mmol), is dissolved in 200 mL of tetrahydrofuran and 15 mL of 10% hydrochloric acid solution is added, and the solution is stirred for 15 hours. To this solution is added sodium hydroxide (3.6 g) and the mixture is stirred for 30 hours. The reaction is stopped by adding 150 mL of water, 90 mL of hexane, and separating the layers. The aqueous layer is acidified with dilute hydrochloric acid solution, stirred for 3 hours and extracted with 150 mL of ethyl acetate. A drop of concentrated hydrochloric acid is added to the ethyl acetate solution and the solution is allowed to stand 18 hours. The solution is concentrated in vacuo and the concentrate is redissolved in 50 mL of ethyl acetate and treated with one drop of concentrated hydrochloric acid. The solution is stirred 2 hours, concentrated in vacuo, and dissolved in 3.0 mL of toluene. (2R-trans)-5-(4-fluorophenyl)-2-(1-methylethyl)-N,4-diphenyl-1-[2-tetrahydro-4-hydroxy-6-oxo-2H-pyran-2-yl)ethyl]-1H-pyrrole-3carboxamide (3.01 g) is isolated in two crops.
Method B
A solution of (4R-cis-1,1-dimethylethyl 6-(2-aminoethyl)-2,2-dimethyl-1,3-dioxane-4-acetate, (Example 2) 2.56 g (9.36 mmol), and (±)-4-fluoro-α-[2-methyl-1-oxopropyl]-γ-oxo-N,β-diphenylbenezenebutaneamide mixture of [R-(R*,R*)], [R-(R*,S*)], [S-(R*,R*)] and [S-(R*,S*)] isomers (Example 3), 3.00 g (7.20 mmol), in 60 mL of heptane:toluene (9:1) is heated at reflux for 24 hours. The solution is cooled and poured into 300 mL of tetrahydrofuran and 150 mL of saturated ammonium chloride in water. The layers are separated and the organic layer is added to 15 mL of 10% hydrochloric acid solution and the solution is stirred for 15 hours. To this solution is added sodium hydroxide (3.6 g) and the mixture is stirred for 30 hours. The reaction is stopped by adding 150 mL of water, 90 mL of hexane, and separating the layers. The aqueous layer is acidified with dilute hydrochloric acid solution, stirred for 3 hours and extracted with 150 mL of ethyl acetate. A drop of concentrated hydrochloric acid is added to the ethyl acetate solution and the solution is allowed to stand 18 hours. The solution is concentrated in vacuo and the concentrate is redissolved in 50 mL of ethyl acetate and treated with one drop of concentrated hydrochloric acid. The solution is stirred 2 hours, concentrated in vacuo, and dissolved in 3.0 mL of toluene. (2R-trans)-5-(4-fluorophenyl)-2(1-methylethyl)-N,4-diphenyl-1-[2-(tetrahydro-4-hydroxy-6-oxo-2H-pyran-2-yl)ethyl]-1H-pyrrole-3-carboxamide (2.92 g) is isolated in two crops.
PREPARATION OF STARTING MATERIALS
EXAMPLE A
4-Methyl-3-oxo-N-phenylpentamide
A three-necked, 12-L round-bottom flask equipped with a mechanical stirrer, a thermometer, and set up for distillation is charged with 2.6 L of toluene, 1.73 kg (12 mol) of methyl 4-methyl-3-oxopentanoate and 72 g (1.18 mol) of ethylenediamine. The mixture is heated to 80° C. and charged with 0.49 kg of aniline. The mixture is brought to reflux and distillation started. After 40 minutes a further 0.245 kg of aniline is charged and at 40-minute intervals a further two portions of aniline (0.245 and 0.25 kg) are charged. Distillation is continued for a further one to five hours until a total of 985 mL of solvent is removed. The solution is stirred at room temperature for 16 hours and a further 550 mL of solvent is removed by vacuum distillation (using approximately 85 mm Hg). The mixture is cooled and 2 L of water is charged to provide an oil. The mixture is warmed to 40° C. and a further 1.0 L of water is charged. Seven hundred milliliters of toluene-water mixture is removed by vacuum distillation (approximately 20 mm Hg). Two liters of water is charged and the mixture is allowed to stand for 10 days. The product is isolated by filtration and washed with three portions of hexane. Drying in vacuo gives 1.7 kg of 4-methyl-3-oxo-N-phenylpentanamide as a hydrate; m.p. 46.5°-58.8° C.
HPLC: 98.8%--retention time 3.56 minutes. 65/35 acetonitrile/water on a dry basis.
VPC: 87.6%--retention time 12.43 minutes, also 10.8% aniline (decomposition). | An improved process for the preparation of (4R-cis)-1,1-dimethylethyl 6-cyanomethyl-2,2-dimethyl-1,3-dioxane-4-acetate is described where a hydroxy ester derivative is converted in two steps to the desired product, as well as valuable intermediates used in the process. | 2 |
FIELD OF INVENTION
[0001] The present invention relates to abrasive disks used in the conditioning of pads in chemical mechanical polishing of silicon wafers of the sort used in the production of integrated circuits. More specifically, the present invention relates to an apparatus and method for extending the service life of disks that are used to condition the polishing pads.
BACKGROUND OF THE INVENTION
[0002] Integrated circuits (ICs) are typically produced en mass upon single, circular semiconductor wafers having diameters of up to about 30 centimeters (cm).
[0003] The semiconductor wafers from which the ICs are cut may have multiple layers of wiring devices on a single wafer. Each layer of circuitry consists of thousands of electrical circuits that will eventually be die cut from the wafer. The successive layers are separated from one another by intervening dielectric layers made of materials such as silicon dioxide. The dielectric and/or metal forming each layers has to be polished or ‘planarized’ before the next layer of circuitry can be deposited. The polishing (or planarization) process is called CMP, which stands for Chemical Mechanical Planarization.
[0004] CMP is superior to previously used planarization technologies because it has proven capable of both local and global planarization of the materials used in the fabrication of multi-level ICs. During CMP, a slurry of fine abrasive particles suspended in liquid chemical solutions react with the surface being polished to achieve the necessary degree of flatness prior to the deposition of the next layer.
[0005] A layer of insulating material, commonly silicon dioxide or variations thereof, is used to separate each successive layer of the fabricated circuitry so that each sequentially deposited IC layer will not, unintentionally, interconnect with subsequent layers of circuitry. In order to pack more devices into less space, the requirements for feature size within the ICs has shrunk dramatically. Features that protrude into or across circuitry layers and make contact where not intended, or do not make contact where intended, can cause short circuits or open circuits and other defects that make an otherwise valuable product unusable.
[0006] One difficulty with CMP is a reduction in the rate at which the CMP pad, or CMP polishing pad, removes material from the wafer being polished and thus the speed of planarization decreases with use. Most conventional polishing pads are made of various kinds of filled or unfilled thermoplastics such as polyurethane. The polishing surface of the pads tends to become glazed and worn during the polishing of multiple wafers. The pad's surface characteristics change sufficiently to cause the polishing performance to deteriorate.
[0007] Deterioration of polishing pad performance is typically reversed by the use of means to ‘condition’ the pad surface during use, or between polishing steps, as needed.
[0008] The pad conditioning procedure uses a conditioning disk that has diamonds or other hard abrasive particles bonded to it. When this disk is applied to the polishing pad it mills away the top surface of the pad exposing fresh asperities and recreating the micro texture in the surface. Conditioning of the pad is also necessary because the surface of the polishing pads undergoes plastic deformation during use, due to pressure and heat.
[0009] Pad conditioning provide a consistent pad polishing performance by periodically regenerating the surface of the pad. Some polishing operations use continuous pad conditioning, others intermittent, some between wafers. The conditioning apparatus generally consists of an arm to which is attached a rotating disk to which is attached the abrasive conditioning surface that rotates while it radially traverses the surface of the rotating polishing pad. The conditioning disk generally has fine diamond grit bonded to its active surface.
[0010] Like the pad, the conditioning disk also undergoes wear of its abrasive surface, requiring that it be replaced periodically in a process that requires stopping of the CMP processing of wafer and a consequent reduction in productivity. Thus the conditioning of polishing pads places service-life constraints upon the conditioning disk. A way to increase the operational of the service life of the conditioning disk is thus a desirable goal.
[0011] It is worth noting that the rotating conditioning disk also radially traverses the polishing pad while renewing the pad surface and restoring polishing pad performance.
[0012] When the conditioning disks are new, the diamond particles are very sharp and quickly ‘roughen’ up the polishing pads. Over time, however, the conditioning effectiveness of the disks decreases until it has to be replaced.
SUMMARY OF THE INVENTION
[0013] According to the present invention, a circular abrasive conditioning disk having a rotational center comprises a plurality of abrasive portions that are independently movable in relation to an active abrasive conditioning surface of a CMP pad. The plurality of abrasive portions are independently movable in a direction that is approximately normal to the plane that defines said active abrasive conditioning surface. The plurality of congruent abrasive portions are arranged in relation to one another in such as way as to comprise a radially symmetrical pattern about the rotational center of the conditioning disk, and at least three of the plurality of independently movable abrasive portions are able to move more or less simultaneously into the plane that defines the active abrasive conditioning surface, and in such as way as to be radially symmetrical about the rotational center of the circular abrasive conditioning disk.
[0014] Also according to the present invention, vertical movement means are provided for precise movement of at least three of the plurality of independently movable abrasive portions into or out of the plane that defines the active abrasive conditioning surface.
[0015] Still further according to the present invention, each congruent abrasive portion of the plurality of congruent abrasive portions is wedge shaped and has a vertex that is oriented approximately toward the rotational center of circular abrasive conditioning disk, said congruency deriving from each of the plurality of wedge shaped abrasive portions having a similar shape and substantially equal characteristic dimensions to the other wedge shaped abrasive portions.
[0016] Yet further according to the present invention, the abrasive segments can also be circular in shape and have diameters that are equal to that of the other circular abrasive portions.
[0017] Still further according to the present invention, each abrasive portion of the plurality of abrasive portions can be other than wedge shaped or circular, so as to be noncircular in shape, but mutually similar in shape and having the same characteristic dimensions as each of the other of the plurality of abrasive portions. Each of the noncircular abrasive portions is disposed in relation to the other noncircular abrasive portions in such a way as to comprise a radially symmetrical pattern about the rotational center of the circular abrasive conditioning disk. At least three of the plurality of independently movable noncircular abrasive portions are able to move more or less simultaneously into the plane that defines the active abrasive conditioning surface, and they are able to move more or less simultaneously into the plane that defines the active abrasive conditioning surface and are disposed in relation to one another in such as way as to be radially symmetrical about the rotational center of the circular abrasive conditioning disk.
[0018] Also, according to the invention, a circular abrasive conditioning disk has a rotational center and comprises a plurality of concentrically arranged and circular abrasive portions that are independently movable in relation to a plane that defines an active abrasive conditioning surface of a CMP pad. Each of the plurality of concentric and circular abrasive portions is independently movable in a direction that is more or less normal to the plane that defines said active abrasive conditioning surface of the CMP pad.
[0019] Further according to the present invention, the means are provided for precise movement of at least one of the plurality of independently movable concentric abrasive portions into or out of the plane that defines the active abrasive conditioning surface of a CMP pad.
[0020] According to the present invention, a method is disclosed by which to extend the operational service life of a circular abrasive conditioning disk. The method comprises the steps of arranging a plurality of independently movable congruent abrasive portions about a common center of rotation having an axis of rotation, and fixing the plurality of independently movable congruent portions having abrasive surfaces in a circular pattern such that the abrasive surfaces of the abrasive portions are in a plane that is perpendicular to the axis of rotation.
[0021] Further according to the present invention, the method also consists of constraining each congruent abrasive portion from radial or tangential motion with respect to the common center of rotation and with respect to one another. Also, means are provided for precise movement of one or more of the independently movable congruent portions into or out of said same plane that is perpendicular to said axis of rotation.
DEFINITION
[0022] The word ‘circular’ refers hereinbelow to the overall shape of the proposed conditioning disk according to the present invention and is to be construed in such a way, as should be readily apparent to those who are skilled in the art, as to include regular polygonal shapes having n sides wherein n is some number greater than two.
BRIEF SUMMARY OF THE DRAWINGS
[0023] The structure, operation, and advantages of the present invention will become further apparent upon consideration of the following description taken in conjunction with the accompanying figures (Figs.). The figures are intended to be illustrative, not limiting.
[0024] Certain elements in some of the figures may be omitted, or illustrated not-to-scale, for illustrative clarity. The cross-sectional views may be in the form of “slices”, or “near-sighted” cross-sectional views, omitting certain background lines which would otherwise be visible in a “true” cross-sectional view, for illustrative clarity.
[0025] In the drawings accompanying the description that follows, often both reference numerals and legends (labels, text descriptions) may be used to identify elements. If legends are provided, they are intended merely as an aid to the reader, and should not in any way be interpreted as limiting.
[0026] FIG. 1 is an oblique schematic view of the prior art CMP system.
[0027] FIG. 2 is an edge-on schematic view of a wafer in contact with a polishing pad that is being conditioned.
[0028] FIG. 3A is an edge-on schematic view of wafer in contact with a polishing pad that is being conditioned, prior to wear away of the asperities.
[0029] FIG. 3B is an edge-on schematic view of wafer in contact with a polishing pad that is being conditioned, subsequent to wear away of the asperities.
[0030] FIG. 4A is an orthogonal view of the abrasive surface a first embodiment of the present segmented conditioning disk.
[0031] FIG. 4B is an edge-on schematic view of the abrasive surface the first embodiment of the present segmented conditioning disk.
[0032] FIG. 5A is a generalized, polygonal embodiment of the present segmented conditioning disk invention.
[0033] FIG. 5B is a four-sided embodiment of the present segmented conditioning disk invention.
[0034] FIG. 6 is an embodiment of the present invention in which the segments are circular.
[0035] FIG. 7 is an embodiment of the present invention wherein the independently movable portions are concentric with one another.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Prior Art and State of the Art System
[0036] FIG. 1 is an oblique schematic, partially cut-away, view of a polishing system 10 for polishing/planarizing the surface of a semiconductor wafer 12 , showing a prior art conditioning disk 14 that is rotationally driven by shaft 14 ′ which can move radially, according to the double-headed arrow 15 , with respect to the center of the polishing pad 16 which is affixed to the rotating platen 18 that is driven by the shaft 18 ′ about the axis A-A′.
[0037] More specifically, the wafer 12 is rotated against the rotating polishing pad 16 (which has a top-most surface 17 ) by means of the rotating head 18 , which is driven by shaft 18 ′. The head 18 can also move radially with respect to the rotating polishing pad, as indicated by the double-headed arrow 19 .
[0038] Referring the FIG. 2 , which is an orthogonal, edge-on schematic edge view of the top-most portion 17 of the polishing pad 16 and the moving wafer 12 , said top-most portion 17 has numerous independent pores 20 that contain a continually refreshed slurry 30 (i.e., indicated by flow arrows 30 ) consisting of fine abrasive material carried in a liquid mixture that might or might not be chemically reactive with the wafer 12 being polished. The slurry 30 is fed to the polishing surface 16 by means of the supply pipe 21 , as shown in FIG. 1 .
[0039] The pores 20 can be characterized as microscratches that are close enough together to form wall structures 22 , portions of which are micro asperities that protrude far enough upward to make intimate contact with the wafer 12 . Arrows 27 , as shown in FIGS. 3A and 3B , indicate relative motions of the pad surface 17 and the wafer 12 . The micro asperities 22 provide contact regions 24 , whereat the slurry 30 reacts with and polishes the surface of the wafer 12 . One can think of the slurry 30 as an abrasive lubricant that moves between wafer 12 and each asperity peak 24 so as to, in effect, pressurize the abrasive slurry against the wafer surface being polished or planarized. The asperity peaks 24 deform somewhat during abrasively lubricated contact with the wafer 12 .
[0040] FIGS. 3A and 3B are schematic edge-on views of the wafer 12 in contact with the top-most surface 17 of the polishing pad 16 , illustrating the effects upon the surface 17 and the asperity peaks 24 and 24 ′ as the polishing process takes place. That is to say, the asperity peaks 24 become worn down to the condition 24 ′, with the deleterious effect upon the polishing process being accordingly degraded by the increased surface areas of the worn peaks 24 ′, which corresponds to reduced pressure between the asperity peaks 24 ′ and the wafer 12 . Deterioration occurs continuously during the polishing/planarizing process. The real contact area increases over time as the asperities make direct push the abrasive slurry 30 against the wafer 12 , the effect being a reduction in the real contact pressure, which causes the material removal rate (from the wafer) to decrease. To achieve constant removal rate and uniformity, it is required to maintain a more or less constant contact area and effective pressure of the slurry 30 against the surface of the wafer 12 being polished. Accordingly, the function of the diamond abrasive conditioning disk 14 ( FIG. 1 ) is to regenerate the sharp-pointed asperities 22 ( FIG. 2 ) on the top-most surface 17 of the polishing pad 16 .
[0041] As material is being removed from the wafer 12 by means of the polishing pad 16 and slurry 30 (in FIG. 2 ), debris also gets deposited into the voids 30 of the top part 17 of the polishing pad 16 . In order to have a consistent pad surface each time a wafer is pressed on the pad, the diamond abrasive conditioner disk 14 ( FIG. 1 ) resurfaces, or conditions or reconditions, the pad 16 . The conditioner 14 is typically a plate with diamonds bonded to it creating an abrasive surface (not shown). However, with repeated use, even diamonds become dull and lose their cutting and conditioning effectiveness. Thus it is the case that the conditioning disk 14 has to be replaced periodically in a process that requires stopping the CMP process and a consequent reduction in manufacturing productivity.
First Embodiment of the Invention
[0042] Whereas the prior art conditioning disk 14 has a single contiguous abrasive surface, the present invention envisions a segmented condition disk 40 , as shown schematically in FIGS. 4A and 4B . The conditioning disk 40 is but one embodiment of the present invention. (Arrows 45 indicate rotary motion and relative motion respectively in FIGS. 4A and 4B .)
[0043] FIG. 4A shows the conditioning disk 40 as comprising congruent pie-shaped segments 42 , of which the exemplary set of twelve segments shown comprise four subsets labeled A, B, C, and D, each of which comprises three segments. The segments 42 are arranged about a common center or axis of rotation 46 in a plane that is perpendicular to said axis of rotation. Each movable and congruent segment 42 is from radial or tangential motion with respect to said axis of rotation, or shared or common center of rotation, and with respect to one another.
[0044] The inventors also envision more or fewer segments 42 , as will be discussed in more detail below. Each of the twelve segments 42 of FIG. 4A are independently movable in a vertical direction, as indicated in the schematic edge-on side view of FIG. 4B ; more specifically, they the inventors envision, in this example of 12 segments, that a radially symmetrical set of any three of them, such as, for example, all segments labeled ‘B’, might be lowered, as shown in FIG. 4B , to engage the surface 44 of pad 16 that is being abraded during the conditioning process. The remaining segments, i.e., A, C and D in FIG. 4B are disposed above the plane of 44 , in a kind of storage position in which they are held in anticipation of future use or when the three segments A have been expended or worn out subsequent to conditioning use.
[0045] The inventors envision that the conditioning disk 40 of FIG. 4A might be mounted upon a swiveling drive shaft (not shown) that will automatically adjust the angle of contact of the segments 42 with the plain of abrasion 44 of surface 17 in such a way as to maintain uniform conditioning pressure and action upon the surface 17 , even if the set of segments 42 that are in abrading contact with the surface 17 are not necessarily radially disposed with respect to the rotational center 46 of the disk 40 . That is to say, the inventors envision that the segmented conditioning disk 40 , according to the present invention, can be used in such a way that, say, for example, two of segments 42 labeled ‘A’ might be used in conjunction with two or three segments ‘D’ and/or ‘B’.
[0046] The inventors further envision a means 43 for the raising and lowering of individual segments or sets of segments 42 , said raising-and-lowering means consisting of such actuators as solenoids, pneumatic or hydraulic pistons, screw drives or the like.
[0047] More generally, the conditioning disk 40 according to the present invention comprises multiple sections/zones 42 , such that specific zones can be activated independently, i.e., moved vertically into or out of contact with the plain of abrasion 44 , which is coincident with the top-most surface 17 of the polishing pad 16 . The schematic side view of FIG. 4B shows three segments 42 , each labeled ‘B’, making contact with the plain of abrasion 44 upon the top-most surface 17 of the CMP pad 16 . That is to say, the three segments 42 are independently movable in relation to an active abrasive conditioning surface 17 of a CMP pad 16 .
[0048] As should be evident to those skilled in the art upon contemplation of FIG. 4A , the segmented conditioning disk 40 according to the present invention can comprise, in general, of n number of segments 42 , where n is greater than at least three. Moreover, those skilled in the art might reasonably surmise that the rounded portion 48 of each segment 42 could as well be a chord 49 , such that said disk 40 would more accurately be describable as having a regular polygonal shape, rather than an overall circular, shape. Hence, the specific definition given above for the adjective ‘circular’ as referring herein to regular polygonal shapes, even though irregular polygonal shapes might also be contemplated by those skilled in the art.
[0049] Thus it is that the object of this invention is concerned with extending the service life and operational consistency of polishing-pad conditioner disks. In its simplest embodiment the individual controlled multiple segment disk 40 ( FIG. 4A ) allows users to move one or more fresh conditioner surfaces into action by activating fresh segments and deactivating spent segments without having to stop the CMP process. An embodiment that offers further control would continue to use the segments as they wear but activate just enough fresh material from unused segments to compensate for the worn segments. In its most refined form, the present invention allows modulation not only of the number of segments in use at any given time but also the pressure applied to each in order to maintain a far more consistent cut rate of the polishing pad then the prior art conditioner disk can generate. As describe hereinabove, the raising-and-lowering means allows various segments or abrasive zones of the invention to be selectively brought into contact with the polishing pad 16 when needed to improve consistency of conditioning operation and consistency of the CMP process. As some of the abrasive segments/zones on the conditioner wear, others can be brought into or removed from action, thus maintaining the cut rate of the disk 40 and extending the time between tool downs for servicing of this part 40 .
[0050] This invention would allow better use of conditioning disks by providing more stable conditioning rate. It is worth mentioning that another alternative is to use several zones or segments 42 to start and then slowly ramp the pressure on one or more other zones to maintain the optimal conditioning rate and desired result.
Additional Embodiments of the Invention
[0051] Those skilled in the art might easily imagine additional ways to provide a conditioning disk having the properties described hereinabove. For example, a conditioning disk 50 , shown in the schematic view of FIG. 5A , is shown comprising a plurality of independently moveable abrasive segments/zones/portions 52 having a collective shape equivalent to a regular polygon of n portions. FIG. 5B is an example of a disk 54 comprising only four portions 56 which add up to a ‘circular’ disk in accordance with the specific definition of ‘circular’ given hereinabove.
[0052] FIG. 6 is an embodiment 60 of a conditioning disk comprised of multiple circular portions or segments 62 , each of which, either independently or in groups, can be raised or lowered to provide conditioning action of a polishing pad. As should be apparent to those skilled in the art, the segments 62 of the embodiment 60 and which are shown in FIG. 6 as having circular shapes need not be constrained only to circular shapes or to other regular shapes such as triangles or polygons.
[0053] FIG. 7 is yet another embodiment of the present invention, wherein a segmented conditioning disk 70 comprises 3 or more or fewer concentric portions/zones 72 , 74 , 76 which can be moved into our out of operation independently or in groups. The circular abrasive conditioning disk 70 has vertical movement means (not shown in FIG. 7 ) that provide for precise movement of at least one of the plurality of independently movable concentric abrasive portions into or out of the plane that defines the active abrasive conditioning surface of a CMP pad.
[0054] Although the invention has been illustrated and described in detail in the drawings and foregoing description, the same is to be considered as illustrative and not restrictive in character—it being understood that only preferred embodiments have been shown and described, and that all changes and modifications that come within the spirit of the invention are desired to be protected. Undoubtedly, many other “variations” on the “themes” set forth hereinabove will occur to one having ordinary skill in the art to which the present invention most nearly pertains, and such variations are intended to be within the scope of the invention, as disclosed herein. | The present invention is an apparatus and method for extending the life of abrasive disks used in the conditioning of polishing pads used in chemical mechanical planarization (CMP) of polishing pads used to polish and/or planarize the surfaces of semiconductor wafers during the production of integrated circuits. The invention consists of the a disk comprising a plurality of abrasive segments, each of which is fixed in tangential and radial relationship to one another about the common axis of rotation of the conditioning disk. Means are provided for movement of the abrasive segments, individually or in sets, into or out of the plane of the active abrasive surface of the conditioning disk according to the present invention. | 1 |
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