description stringlengths 2.98k 3.35M | abstract stringlengths 94 10.6k | cpc int64 0 8 |
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FIELD OF THE INVENTION
The present invention concerns a mechanical device able to:
limit the force of a linear electric jack with a reversible screw/nut system,
limit the static force supported by the jack on stopping,
disengage the screw of the jack from its drive system so as to render it translation-free.
BACKGROUND OF THE INVENTION
The solution currently used consists of uncoupling the reversible screw/nut system from its drive motor by means of a claw coupling controlled externally or by a lever whose movement depends on the axial force applied to the screw of the jack.
The external mechanical device located between the load and the screw of the jack drives the lever when the force exceeds a pre-established value.
The drawbacks of this system are:
the rapid wear of the claw coupling device,
the wear of each element of the device has an effect on the adjustment which needs to be regularly reset,
the device activating the lever requires a significant axial movement which causes inaccuracy concerning the positioning of the load linked to the jack,
it only functions in a single direction,
the production of this system is complex.
SUMMARY OF THE INVENTION
The device of the invention is able to resolve these drawbacks.
This device includes two elements, one integral with the screw of the jack and the other integral with the load able to rotate with respect to the other on a given axis. The axial translation movement between these two elements cannot take place.
Disposed between these two elements is a friction system. At rest, the rotation of the two elements with respect to the other is prevented by this friction system. The screw of the jack is therefore rendered integral with the load and this blocks rotation of this screw and creates a torsion torque on the friction system when the jack is functioning.
Two cases of functioning appear:
1. Dynamic force limiter of the jack when the latter moves the load:
The friction torque between the screw and the nut tends to move the screw in rotation. This rotation is prevented until the friction system slides and separates the screw from the load which is no longer translation-driven.
This therefore produces a limitation of the force of the jack.
2. Static force limiter supported by the jack when the latter does not move the load:
The device uses the reversibility of the screw/nut system.
Reversibility means that, under the action of an axial force on one of the screw or nut elements, the other, blocked in an axial direction, starts to rotate.
The force applied by the load in the axis of the screw tends to drive it in rotation. This rotation is prevented until the friction system slides and separates the screw from the load.
The rotation of the screw causes the latter to advance into the nut and actuates a linear movement of the load.
This device functions both on traction and on compression.
The friction system used may be a device with balls, friction disks, multipolar permanent magnets or be of another type.
When the jack has stops for cutting off feeding of the drive motor when the end of travel is reached, the device of the invention involves the use of end of travel stops whose functioning is symmetrical around the axis of the jack as the screw is rotating.
These stops ensure the same total travel of the rotating screw, regardless of its angular position.
According to particular embodiments, the end of travel stops can be made up of:
a circular mechanical element associated with an electric power circuit breaker, a pneumatic or optical detector or another type of detector.
an annular magnet associated with a dry contact magnetic detector or a <<Hall>> effect detector using a semiconductor or similar type of device.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings illustrate the invention:
FIG. 1 is a cutaway view of the device of the invention.
FIG. 2 is a cutaway view of a first variant of this device.
FIG. 3 is a cutaway view of a second variant of this device.
FIG. 4 is a cutaway view of a variant of the device according to FIG. 2.
FIG. 5 is a cutaway view of a third variant of the device of FIG. 1.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
With reference to these drawings, the jack itself, which has been simplified so as to understand the invention, comprises a body (15) containing a nut (8) immobilised along the axis between two rolling stops (12) acting against end surfaces of nut (8). This nut is driven in rotation with the aid of a motor (11) by means of a gear train with two pinions (9) and (10). The nut (8) moves the screw (7) which transforms the rotating movement of the nut into a translation movement of this screw. The load (17), activated by the screw, can only undergo a translation movement with respect to the body (15) secured to a structure. The element (1) integral with the load is therefore blocked in rotation with respect to the body (15). On stoppage of the jack, the nut (8) is immobilised in rotation by a suitable electromechanical device (not shown).
According to particular embodiments:
The jack may be equipped with a screw (7)/nut (8) with balls or any type of thread with a fast pitch to favour reversibility.
The screw (7) and nut (8) can be inverted, the nut moving in translation by means of the rotating screw. In this case, the screw (7) and nut (8) need to be inverted as regards the entire description of the device of the invention.
With reference to FIG. 1, the device of the invention comprises an element (2) rendered integral with the screw (7) of the jack with the aid of an assembling element (6), and an element (1) integral with the load (17) by means of the pin (18).
These two elements (1) and (2) are able to rotate with respect to each other around the same axis, but are unable to move in translation with respect to each other along this axis. They can be concentric and circular, one of them forming a protection covering cap around the whole device.
A friction system (3), which acts as a torsion torque limiting device situated between the elements (1) and (2), provides the link between these two elements. The friction system (3) is therefore subjected to a torsion torque by the fact that it blocks rotation of the screw (7).
There are two cases of functioning:
1. Dynamic force limiter of the jack when the latter moves the load (17):
The friction torque between the screw (7) and the nut (8) tends to move the screw in rotation. This rotation is prevented until the friction system (3) slides and separates the elements (1) and (2). The value of the force from which rotation occurs depends on the adjustment of the friction system.
2. Static force limiter supported by the jack when the latter does not move the load (17):
The device uses the reversibility of the screw (7)/nut (8) system. The force applied by the load (17) in the axis of the screw (7) tends to screw the latter into the nut (8). This generates a torsion torque to the element (2) transmitted to the element (1) by means of the friction system (3).
The rotation of the screw (7) is prevented until the friction system (3) slides and separates the elements (1) and (2).
The value of the force from which rotation occurs depends on the adjustment of the friction system.
In the embodiment shown on FIG. 2, the friction system (3) is replaced by a ball friction system. The device comprises an element (2) rendered integral with the screw (7) of the jack with the aid of a pin (6) for example, and an element (1) integral with the load (17) activated by the jack.
These two elements are concentric and are able to rotate with respect to each other around the same axis.
An assembly composed of rolling bearing stops (4) and (5), the rolling bearing (21) and the backplate (23) stopped by the elastic ring (22) allows rotation between the elements (1) and (2) whilst transmitting the axial forces.
The element (2) comprises one or several recessed holes in each of which slides a ball (19) pushed by a spring (20). The element (1) comprises notches (28), the number of these being more than the number of balls (19) and housing these balls.
There are two cases of functioning:
1. Dynamic force limiter of the jack when the latter moves the load:
The friction torque between the screw (7) and the nut (8) tends to drive said screw in rotation. This generates a torsion torque to the element (2) transmitted to the element (1) by means of the balls (19) pushed by the springs (20).
The rotation of the screw (7) is prevented until the balls (19) escape from the notches (28), thus compressing the springs (20) under the action of the torsion torque.
The value of the force from which rotation occurs depends on the efficiency of the screw (7)/nut (8) system, the value of the stiffness of the springs (20), as well as the shape and dimensions of the elements making up the device.
2. Static force limiter supported by the jack when the latter does not move the load:
The device uses the reversibility of the screw/nut system.
The axial force exerted on the screw (7) tends to screw the latter into the nut (8). This generates a torsion torque on the element (2) transmitted to the element (1) by means of the balls (19) pushed by the springs (20).
The rotation of the screw (7) is prevented until the balls (19) escape from the notches (28), thus compressing the springs (20) under the action of the torsion torque.
The value of the force from which rotation is produced depends on the efficiency of the screw (7)/nut (8) system, the value of the stiffness of the springs (20) and the shape and dimensions of the elements constituting the device.
According to particular embodiments:
The balls (19) can be replaced by rollers, blocks or bolsters of any shape.
The elements (1) and (2) can be inverted, the notches (28) then being located on the element (2).
In the embodiment shown on FIG. 3, the friction system (3) is replaced by a disk friction system.
The element (2) integral with the screw (7) of the jack comprises a disk (24). The element (1) integral with the load (17) comprises a disk (25) able to move along the axis plated against the disk (24) by the spring (26). The disk (25) cannot rotate with respect to the element (1), the pin (27) blocking its rotation. The elements (1) and (2) can rotate with respect to each other around the same axis.
The thrust roller bearings (4) and (5) permit rotation of the element (2) with respect to the element (1) whilst transmitting the axial forces.
The moment of the torque from which sliding of the disks (24) and (25) in relation to each other occurs depends on the stiffness of the spring (26), the friction coefficients of the disks and their surface area.
The two cases of functioning are identical to those of the embodiment of FIG. 1.
The embodiment of FIG. 4 is derived from that of FIG. 2. The device is modified so as to limit the force applied to the screw (7) of the jack solely in a single direction. As regards the other direction, the device is blocked and does not limit the force. Housings (29) cut in the element (2) enable the balls (19) pushed by the springs (20) to move tangentially to the element (2) and in a single direction when rotation between the elements (1) and (2) starts to occur. The balls are then engaged in the housings (29), can no longer move radially inside the element (2) and the springs (20) can no longer be compressed.
The depth of the housings (29) is such that the balls (19) remain blocked inside the notches (28) and prevent free rotation between the elements (1) and (2):
the dynamic force is no longer limited in an axial direction corresponding to the position of the housings (29) when the jack moves the load (17),
the static force supported is no longer limited in an axial direction corresponding to the position of the housings (29) when the jack does not move the load.
When the torsion torque reduces and changes direction, the device is unblocked and the balls (19) return to the axis of the springs (20) which can again be compressed. The device then behaves like that of FIG. 2 and acts as a force limiter.
The housings (29) can be cut on either side of the balls (19) along the desired locking direction. The number of said housings can be equal to or less than the number of balls. These housings are all embodied in the same direction.
The device of FIG. 1 can be modified so as to transform it into a system for disengaging the rod of the jack. In this variant, the friction system (3) is replaced by a coupling. This coupling, associated with an external control device, makes it possible to:
render integral the elements (1) and (2) if the disengaging control is not activated. The jack can then push or pull the load (17) with all the force required.
instantly separate the elements (1) and (2) if the disengaging control is activated. This renders the screw (7) fully free in rotation and translation with respect to the nut (8) as the screw(7)/nut (8) system is reversible. The screw (7) and the load (17) attached to it are then free in translation along their axis with respect to the body (15) of the jack.
The functions for limiting the force and for disengaging the screw (7) can be combined inside a given box so as to obtain a jack with limited force and with a screw (7) able to be disengaged in translation with respect to the body (15) where the electric power has been cut from its motor, for example.
In the embodiment shown on FIG. 5, the coupling is made up of a blocking finger (31) pushed by a spring (32). This finger renders the elements (1) and (2) integral at rest. Action of the lever (34) articulated around the axis (33) secured to the element (1) lifts up the blocking finger (31), thus compressing the spring (32) and renders the elements (1) and (2) able to rotate freely with respect to each other. In this case, the screw (7) rotates freely and can be screwed freely onto and unscrewed freely from the nut (8).
According to particular embodiments, the action on the lever (34) can be effected manually or by any electromechanical, pneumatic or mechanical control device.
The functioning of the two end of travel stops (13) integral with the screw (7) is symmetrical around the axis of the screw (7), that is regardless of the angular position of said screw.
These stops (13) can be made up of:
an annular magnet (16) with an axial field which, without any contact, controls a detector (14) sensitive to the magnetic field of standard glass bulb dry contacts, a <<Hall>> effect detector or other type of detector.
a circular mechanical element controlling an electric power circuit breaker, an optical detector, pneumatic detector or other type of detector.
The detectors (14) situated inside the body (15) of the jack generate a signal which can be used to control stoppage of the motor (11) when the end of travel has been reached.
These end of travel stops (13) are circular. | The invention concerns a device making it possible to firstly limit the dynamic or static force applied to a linear electric jack with a reversible screw/nut system, and secondly translation-disengage the screw of the jack. This device is formed of an element (2) integral with the screw (7) of the jack and an element (1) integral with the activated load and interconnected by a friction system (3). The force applied on the screw (7) tends to make the latter rotate inside the screw (8) of the jack. This rotation is stopped by the friction system (3) until the latter slides and separates the elements (1) and (2). The screw (7) then rotates with respect to the element (1) which limits the force. The replacement of the friction element (3) by a coupling makes it possible to externally control the rotation and translation of the screw (7). The end of travel stops (13) secured to the screw (7) rotate with this screw whilst retaining their characteristics. | 5 |
CROSS-REFERENCE TO RELATED APPLICATIONS
Not applicable.
STATEMENT CONCERNING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
Not applicable.
FIELD OF THE INVENTION
The invention relates to fabrics for manufacturing non-woven textiles and paper products.
BACKGROUND OF THE INVENTION
Non-woven textiles, or simply “non-wovens”, are well-known products formed from webs of randomly arranged and entangled fibers. In most cases, the fibers of non-wovens are bonded to each other, for example, adhesively, mechanically, thermally, or chemically. Non-wovens may be single use products with relatively low strength, such as hygienic wipes and the like. Non-wovens may also be stronger and more durable products, such as medical gowns and geotextiles.
Processes for forming non-wovens typically involve forming the fiber web on a structure of interwoven yarns, typically referred to as a forming fabric. These processes include, for example, wet forming, carding, spunbonding, and meltblowing. In both spunbonding and meltblowing processes, the fibers are formed of a molten polymer that is extruded through a die and eventually collects on the forming fabric. The molten polymer may be, for example, polyethylene terephthalate (PET), polyethylene (PE), polypropylene (PP), or copolymers of PET and PE, and the forming fabric is typically formed of PET yarns.
Both spunbonding and meltblown processes can occasionally produce drops of the molten polymer that adhere to the forming fabric. In some cases, adherence and accumulation of the molten drops can cause blemishes, burn holes, or other surface defects on the forming fabric. These defects can reduce the quality of non-wovens formed on the forming fabric; for example, a damaged forming fabric can create products with relatively rough surfaces or other undesirable characteristics. In most cases, it is easiest to replace a defective forming fabric with a new forming fabric.
Further still, in some cases the molten polymer drops can penetrate the web-facing side and accumulate within the fabric, thereby reducing the permeability and the usefulness of the fabric. Certain well-known chemicals, such as sulfuric acid (H 2 SO 4 ) for PET and toluene or methyl ethyl ketone (MEK) for PE, could be used to dissolve the polymer drops; unfortunately, such chemicals would also damage the PET yarns of the forming fabric. As a result and as described above, it is easiest to replace a defective forming fabric with a new forming fabric.
Considering the limitations of previous fabrics, it would be desirable to have a fabric with heat resistance to resist damage from molten polymer drops produced in some non-woven forming processes. It would also be desirable for such a fabric to resist corrosion from common chemicals, such as chemicals that dissolve the polymer residues but do not harm the base fabric. Further still, it would also be desirable for such a fabric to dissipate static electricity in some cases; that is, it would be desirable for such a fabric to act as an antistatic fabric. Further still, it would be desirable for such a fabric to have a smooth upper surface, including in some cases, the seam between ends or different sections of the fabric.
SUMMARY OF THE INVENTION
In one non-limiting aspect, the present invention provides a fabric for supporting a fibrous web. The fabric comprises a layer that includes a plurality of weft yarns and a plurality of warp yarns interwoven with the plurality of weft yarns. The warp and weft yarns define a web-facing side and an opposite machine-facing side. The warp yarns comprise at least one of polyphenylene sulfide (PPS) and polyetheretherketone (PEEK). In addition, a yarn count, weave pattern, and yarn shape of the fabric are configured such that molten polymer drops are scrapable from the web-facing side leaving a support surface that does not blemish a fibrous web supported by the fabric.
In another non-limiting aspect of the invention, the fabric comprises a layer that has a web-facing side and a machine-facing side. The layer includes a plurality of weft yarns that comprise at least one of polyphenylene sulfide (PPS) and polyetheretherketone (PEEK). The layer further includes a plurality of warp yarns interwoven with the plurality of weft yarns. The warp yarns comprise at least one of PPS and PEEK. At least some of the warp yarns define floats over at least five consecutive weft yarns and have flat upper surfaces such that molten polymer drops do not penetrate an upper plane of the web-facing side.
The foregoing and other objects and advantages of the invention will appear in the detailed description which follows. In the description, reference is made to the accompanying drawings which illustrate a preferred embodiment of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will hereafter be described with reference to the accompanying drawings, wherein like reference numerals denote like elements, and:
FIG. 1 shows an exemplary weave repeat of a fabric according to the invention;
FIG. 2 is a schematic representation of the weave pattern of individual warp yarns with weft yarns of the fabric of the invention;
FIG. 3 is a side view of the weave pattern of several warps yarns with several weft yarns;
FIG. 4 is a view of a machine-facing side of the fabric of the invention;
FIG. 5 is a top view of a spiral or “spiro-pin” seam connecting ends of the fabric of the invention;
FIG. 6 is a side view of one end of the spiro-pin seam and the fabric of the invention; and
FIG. 7 is a top view of a double loop pin seam connecting ends of the fabric of the invention.
DETAILED DESCRIPTION OF THE INVENTION
The particulars shown herein are by way of example and only for purposes of illustrative discussion of the embodiments of the invention. The particulars shown herein are presented to provide what is believed to be the most useful and readily understood description of the principles and conceptual aspects of the invention. In this regard, no attempt is made to show structural details of the invention in more detail than is necessary for the fundamental understanding of the invention. The description taken with the drawings and photographs should make apparent to those skilled in the art how the several forms of the present invention may be embodied in practice.
It is noted that while the discussion of the invention that follows may refer specifically to forming fabrics in the non-wovens industry, the invention is applicable to other fabrics in the papermaking industry and other industrial applications. For example, the fabric of the invention may be used as an oven fabric or a dryer fabric on a papermaking machine.
Further, when an amount, concentration, or other value is given as a range of preferable upper values and preferable lower values, this should be understood as specifically disclosing all ranges formed from any combination of a preferable upper value and a preferable lower value, regardless of whether ranges are separately disclosed.
Referring to FIGS. 1-7 , the fabric of the invention includes a layer 10 , such as the base layer of the fabric, that has a web-facing side 12 and a machine-facing side 14 . The layer 10 comprises interwoven warp (machine direction) yarns and weft (cross-machine direction) yarns. By way of non-limiting example, FIGS. 1-7 show a fabric having one layer of weft yarns. However, it is contemplated that the fabric may include any number of layers of weft yarns. Those skilled in the art would modify the number of layers based on any number of parameters, such as fabric length, weight and strength requirements, desired permeability, the type of product being produced, and the like. By way of non-limiting example, the fabric preferably has from one to three layers of weft yarns, and most preferably one or two layers of weft yarns.
Each warp yarn is made of a high temperature thermoset polymer; preferably polyphenylene sulfide (PPS), although polyetheretherketone (PEEK) may be used in some embodiments. In some embodiments, each warp yarn is a monofilament yarn made of extruded PPS or PEEK polymeric resin material plus any other appropriate material used in the manufacture of industrial process fabrics and paper machine clothing. However, each warp yarn may be a plied monofilament or the like. Each weft yarn is also preferably made of PPS, although in some embodiments PEEK or polyester may be used, and is a monofilament, plied monofilament, or the like.
Warp and weft yarns comprising PPS and/or PEEK advantageously provide a heat-resistant fabric layer 10 . As such, the web-facing side 12 and other parts of the fabric layer 10 resists blemishes and damage caused by molten polymer drops occasionally formed during certain processes, such as spunbonding and meltblowing. Instead, the molten drops solidify on the web-facing side 12 and typically do not adhere to the fabric. However, an operator may use a scraper to remove any residual polymer drops that adhere to the fabric without damaging the fabric. As a result, the fabric does not form blemishes on the non-woven web after residual polymer drops are removed from the fabric. In addition, warp and weft yarns comprising PPS and/or PEEK advantageously provide a fabric layer 10 that resists corrosion caused by well-known cleaning chemicals, such as sulfuric acid for PET, solvents such as toluene or methyl ethyl ketone (MEK) for PE, or sulfuric acid followed by MEK for copolymers of PET and PE. As a result, instead of using a scraper, an operator may use these chemicals to dissolve any residual polymer drops without damaging the fabric.
In some embodiments, some of the weft yarns are antistatic yarns in order to provide a fabric layer which dissipates static electricity that accumulates during some dry forming processes. The antistatic yarns may be formed of carbon-impregnated nylon, metal, conductive PPS or conductive PEEK and conductive nylon using techniques described in U.S. Pat. No. 7,094,467, the disclosure of which is hereby incorporated by reference in its entirety. In these embodiments, the fabric may also include additional features, such as conductive edging, to form an electrostatic grid that dissipates static electricity.
It is contemplated that the fabric layer may use differing shapes and sizes for the yarns. For example, the warp yarns may have a greater thickness than the weft yarns, or vice versa. In some embodiments, the warp yarns may be round or circular with diameters in the range of 0.10 mm to 1.20 mm. However, in a preferred embodiment, the warp yarns have flat upper surfaces 16 ( FIG. 3 ) that define a large portion of the web-facing side 12 . The flat upper surfaces 16 may be formed by grinding the web-facing side 12 of the fabric, or, preferably, by using warp yarns with rectangular cross-sections. The rectangular warp yarns, if used, preferably have width and height dimensions in the range of 0.40 mm to 1.20 mm, and are most preferably 0.63 mm wide by 0.37 mm high. These preferred shapes and sizes advantageously reduce the mesh (number of warp yarns per inch) of the fabric by one half compared to previous designs.
The flat upper surfaces 16 of the warp yarns provide a sufficiently solid and flat support surface on the web-facing side 12 from which polymer drops can be removed easily with a scraper. That is, the molten polymer drops do not penetrate an upper plane of the fabric. The term “upper plane” should be understood to mean a plane beyond which polymer drops would create a mechanical form fit or wrap around yarns of the fabric. For example, the upper plane for a layer of round yarns would pass through the centers of the yarns. In contrast, the upper plane for a layer of rectangular yarns is at the bottom surface of the yarns. In any case, polymer drops cannot be removed easily with a scraper if the polymer drops flow past the upper plane, and an attempt to do so may damage the fabric. As a result, the surface tension of the polymer drops is preferably considered and the shapes and spacing between yarns are selected such that the polymer drops do not penetrate the upper plane of the fabric.
The weft yarns may be, for example, circular, oval-shaped, circle-like or oval-like as shown in FIGS. 3 and 6 . The weft yarns preferably have a diameter in the range of 0.10 mm to 1.20 mm and most preferably 0.70 mm. In embodiments in which some of the weft yarns are antistatic yarns, the antistatic yarns preferably have a diameter in the range of 0.10 mm to 1.10 mm and most preferably 0.28 mm.
In a preferred embodiment, the warp and weft yarns are woven as shown specifically in FIGS. 1-4 . FIG. 1 shows a single repeating pattern area, or a “weave repeat”, of the fabric layer that encompasses four warp yarns (yarns 1 - 4 extending vertically in FIG. 1 ) and eight weft yarns (yarns 1 - 8 extending horizontally in FIG. 1 ). In some embodiments, some of the weft yarns, for example, the even-numbered weft yarns, are antistatic weft yarns as described above. In FIG. 1 , the symbol ‘X’ represents a position where a warp yarn passes over a weft yarn (e.g., warp yarn 1 passes over weft yarn 2 ) as viewed from the web-facing side of the fabric. Conversely, an empty box represents a position where a warp yarn passes under a weft yarn (e.g., warp yarn 1 passes under weft yarn 1 ) as viewed from the web-facing side of the fabric. FIG. 2 depicts the paths of warp yarns 1 - 4 as they weave with weft yarns 1 - 8 . While FIGS. 1 and 2 only show a single section of the fabric, those of skill in the art will appreciate that in commercial applications the pattern shown in FIGS. 1 and 2 would be repeated many times, in both the warp and weft directions, to form a large fabric suitable for creating non-wovens.
Referring to FIGS. 1 and 2 , each warp yarn weaves the same pattern with the weft yarns. That is, each warp yarn passes over five consecutive weft yarns, and then passes under three consecutive weft yarns. For example, warp yarn 1 passes over weft yarns 2 - 6 , and then passes under weft yarns 7 , 8 , and 1 . However, it should be noted that the pattern is offset between adjacent warp yarns; specifically, the pattern of one adjacent warp yarn is offset by four weft yarns, and the pattern the other adjacent warp yarn is offset by two weft yarns. For example, the last weft yarn passed over by warp yarn 2 is weft yarn 2 , the last weft yarn passed over by warp yarn 1 is weft yarn 6 (i.e., an offset of four weft yarns), and the last weft yarn passed over by warp yarn 3 is weft yarn 4 (i.e., an offset of two weft yarns).
Each warp yarn defines a long warp float by passing over five consecutive weft yarns. These warp floats define a large portion of the web-facing side. Further still, the long warp floats advantageously contribute to the smoothness of the web-facing side. As described above, the smooth web-facing side permits polymer drops to be removed easily. It is also contemplated to use warp floats of other lengths because warp floats of any length (i.e., passing over two or more consecutive weft yarns) advantageously provide a web-facing side with some degree of smoothness. However, it is preferred to use warp floats that pass over less than six consecutive weft yarns to ensure that the fabric layer is relatively stable.
As described above, the long warp floats define a large portion of the web-facing side. However, weft floats that pass over two consecutive warp yarns (e.g., weft yarn 5 passes over warp yarns 2 and 3 ) also define a portion of the web-facing side. The weft floats are recessed compared to the long warp floats, and as a result, the weft floats define pockets on the web-facing side. The short length of the weft floats and pockets advantageously provide a sufficiently solid and flat support surface that prevents polymer drops from penetrating the upper plane of the web-facing side and creating a mechanical form fit with the fabric. Instead, polymer drops remain on the web-facing side and can be removed easily.
The fabric of the invention preferably has a permeability in the range of 50 cfm to 1200 cfm and most preferably about 500 cfm. The fabric preferably has a caliper in the range of 1 mm to 4 mm and most preferably about 1.5 mm. However, those skilled in the art will appreciate that the aforementioned characteristics depend on the yarn shape, yarn size and the weave pattern. As a result, appropriate permeability and caliper ranges may vary depending on the specific fabric design.
The fabric of the invention may be formed as an endless belt without using additional components. However, in some embodiments, a well-known seam connects ends of the fabric layer to form a belt. Referring to FIGS. 5 and 6 , the fabric preferably includes a spiral or “spiro-pin” seam 18 to connect the ends of the fabric. Referring to FIG. 6 , one side of the spiro-pin seam 18 includes first and second anchor yarns 20 and 22 that support a spiral yarn 24 that extends in the weft direction. The first anchor yarn 20 also supports portions of the warp yarns proximate the seam 18 , and the portions of the warp yarns are rewoven with adjacent weft yarns. Referring to FIG. 5 , the spiral yarn 24 meshes with a second spiral yarn 26 on the opposite end of the fabric to form the endless belt.
In some embodiments, the seam may be a single loop seam; such a seam is well-known to those skilled in the art. Further still, in some embodiments, the seam may be a double loop pin seam 28 as shown in FIG. 7 . The double loop pin seam 28 includes first and second anchor yarns 30 and 32 that support first and second offset yarn loops 34 and 36 on each end of the fabric layer. The first and second yarns loops 34 and 36 are formed from portions of the warp yarns, and each weave repeat includes one set of first and second yarn loops 34 and 36 . Other aspects of double loop pin seams are well-known to those skilled in the art. Regardless of the type of seam used, the seam preferably has the same permeability and caliper as other areas of the fabric to provide a non-marking fabric belt. In addition, the components of the seam (e.g. the anchor yarns and the spiral yarns) are preferably made from the same material as the warp and weft yarns (e.g., PPS or PEEK) to prevent damage from polymer drops and corrosion from cleaning chemicals.
The fabric layer of the invention is preferably manufactured as follows: first, the warp and weft yarns are woven using well-known techniques. The fabric is unstable and the yarns do not mesh well with one another after weaving because yarns formed from PPS and/or PEEK are relatively rigid compared to other types of yarns. The fabric is heat set and stretched to address this issue, and the yarns mesh with one another to provide a stable fabric. Next, if the fabric is to include a seam, yarns proximate the ends of the fabric are fringed and the warp yarns are rewoven with the seam components and the weft yarns. The fringed yarns are then clipped flushly with the web-facing or machine-facing side of the fabric to maintain the smoothness of the fabric. Finally, the seam is heat set so that the seam is in-line with other areas of the fabric and to ensure the seam is non-marking.
From the above disclosure it should be apparent that the fabric of the present invention can provide any combination of the following advantages: heat resistance and resistance to damage from molten polymer drops; corrosion resistance to chemicals that dissolve polymer drops; light weight and high strength; high permeability; and use of a heat and corrosion-resistant non-marking seam.
EXAMPLE
A fabric for a non-wovens application was woven on a loom utilizing Voith's weave pattern #24 plus a stuffer. The fabric included rectangular PPS warp (machine direction) yarns that were 0.63 mm wide by 0.37 mm high at 44 ends per inch. The weft (cross-machine direction) yarns had a diameter of 0.70 mm and alternated with 0.28 mm diameter carbon-impregnated nylon antistatic yarns at 30 picks per inch. The fabric was heat set at 480 degrees F. and stretched to 30 pli. The fabric was cut to length and then prepared for seaming. PEEK spiral yarns were installed at both ends and joined. The fabric was then cut to finished width and heat sealed. A carbon loaded adhesive was applied over a width of 1″ along both edges. The carbon edge formed an electrostatic grid to dissipate static electricity accumulated during formation of non-wovens or paper products.
It is noted that the foregoing examples have been provided merely for the purpose of explanation and are in no way to be construed as limiting of the present invention. While the present invention has been described with reference to exemplary embodiments, it should be understood that the words that have been used are words of description and illustration, rather than words of limitation. Changes may be made, within the purview of the appended claims, as presently stated and as amended, without departing from the scope and spirit of the present invention in its aspects. Although the invention has been described herein with reference to particular arrangements, materials and embodiments, the invention is not intended to be limited to the particulars disclosed herein. Instead, the invention extends to all functionally equivalent structures, methods and uses, such as are within the scope of the appended claims. | A fabric for supporting a fibrous web is disclosed. The fabric has a layer that includes a plurality of weft yarns and a plurality of warp yarns interwoven with the plurality of weft yarns. The warp and weft yarns define a web-facing side and an opposite machine-facing side. The warp yarns include at least one of polyphenylene sulfide (PPS) and polyetheretherketone (PEEK). In addition, a yarn count, weave pattern, and yarn shape of the fabric are configured such that molten polymer drops are scrapable from the web-facing side leaving an upper support surface that does not blemish a fibrous web supported by the fabric. | 3 |
RELATED APPLICATION
[0001] This application claims priority to Korean Patent Application No. 2001-59954, filed on Sep. 27, 2001, the contents of which are herein incorporated by reference in their entirety.
FIELD OF THE INVENTION
[0002] The present invention relates to integrated circuit devices, more particularly, to circuits and methods for protecting integrated circuits from electrostatic discharge.
BACKGROUND OF THE INVENTION
[0003] A thrust of integrated circuit design has been the development of integrated circuits capable of higher frequency operation and/or lower power consumption. The ability of an integrated circuit to operate at high frequencies with low power consumption is generally determined by characteristics of active and passive elements in the integrated circuit, such as resistance and parasitic capacitance.
[0004] Referring to FIGS. 1A, 1B, and 1 C, in order to reduce the drain and source resistances Rd, Rs of an NMOS transistor 10 ′ or a PMOS transistor 10 ″, silicide layers SA comprising a low-resistance metallic material and silicon are formed on surfaces of a polysilicon gate GP, a source S, and a drain D using a self-aligned silicidation (hereinafter “salicidation”) process. In applying the salicidation process, a discharge space for the transistor is defined at a region A at a junction disposed under a spacer GS adjacent the polysilicon gate GP. When electrical transients arising from electrostatic discharge (ESD) or electrical overstress (EOS) occur at a pad (not shown) connected to one of the source S or the drain D, the discharge space A may not be sufficiently large enough to prevent physical damage.
[0005] Input/output circuits are commonly designed to protect internal portions of an integrated circuit from transients arising from ESD, EOS, peak voltage, current surge, or noise. They also commonly provide voltage conversion between the voltage used by the internal portions and the voltage used by externally connected circuits, e.g., conversion of signals from CMOS to TTL or from TTL to CMOS. Input/output circuits also often include transistors with larger channel widths that can support higher currents which may arise from resistance, inductance, and capacitance of a printed circuit board (PCB) on which the integrated circuit is mounted and cables connecting the integrated circuit to external systems.
[0006] For example, a structure, as shown in FIG. 2A, that includes multiple transistors including a plurality of polysilicon gate layers 3 formed on a diffusion region 1 including source and drain regions S, D may be used. As can be seen in the cross-section in FIG. 2B, the substrate P-sub and the source and drain regions S, D form parasitic horizontal NPN bipolar transistors Q 1 , Q 2 that provide a discharge path. Resistances between the bases of the parasitic transistors Q 1 , Q 2 can prevent simultaneous turn-on of the transistors Q 1 , Q 2 . Therefore, it may take a significantly long time for all of the transistors Q 1 , Q 2 to be turned on to provide a discharge path in response to an electrical transient. In the structure illustrated, the turn-on time of all the bipolar transistors Q 1 , Q 2 is generally dependent upon values of on-resistance determined by dimensions of overlapped regions between the polysilicon gates 3 and the drains D. However, as described above, a relatively small on-resistance may be provided by a transistor fabricated by a salicidation process, which may provide insufficient RC delay time to enable a desired level of conduction of the transistors Q 1 , Q 2 . This can result in insufficient ESD protection.
[0007] A protection circuit, such as a diode or silicon-controlled rectifier (SCR), may be used to provide ESD protection for an output drive circuit that includes MOS transistors produced by a salicidation process. It is generally desirable to provide a protection circuit capable of driving a large current at a relative low voltage, as it is generally desirable that the protection circuit discharge excessive transients before the MOS transistors of the output drive circuit exhibit break down. However, it may be difficult to provide a protection circuit with high current capability at a relatively low turn-on voltage.
[0008] One way of dealing with this problem is to raise the turn-on voltage of the output drive circuit. For example, turn-on voltage may be raised by increasing a base width of a parasitic LNPN bipolar transistor associated with a MOS transistor of a drive circuit. However, increasing the base width of a parasitic LNPN associated with an output drive circuit MOS transistor can result in a need to increase circuit area to compensate for lower current drivability.
[0009] [0009]FIG. 3 illustrates another way to increase the turn-on voltage of an output circuit 100 including a PMOS transistor 101 and an NMOS transistor 102 that drive an external signal pad PAD and are protected by a protection circuit 20 . As shown, turn-on voltage of the NMOS transistor 102 may be increased by placing a resistor Rs in series with the NMOS transistor 102 . This can restrain activation of a parasitic LNPN, but, as with extending base width, can lead to increased circuit area to offset weak current drivability due to the additional resistor.
[0010] Another technique to protect a breakdown of an NMOS transistor by raising a turn-on voltage of an output circuit beyond that of a protection circuit is shown in FIGS. 4 A- 4 F. In particular, a base width of a parasitic LNPN can be extended by connecting NMOS transistors of an output circuit 110 and a protection circuit 120 in series.
[0011] Two ways of connecting the transistors are shown in FIGS. 4 B- 4 C and FIGS. 4 D- 4 E, respectively. Referring to FIGS. 4B and 4C, active regions of two NMOS transistors N 1 and N 2 are separated, and a source of the NMOS transistor N 1 is connected by a metal line M to a drain of the NMOS transistor N 2 , which is grounded. FIGS. 4D and 4E show a configuration where the source of the NMOS transistor N 1 and the drain of the NMOS transistor N 2 are connected through an active region, which can more efficiently use circuit area.
[0012] Although the configurations shown in FIGS. 4 B- 4 E can extend a base width between a drain connected to a pad PAD (i.e., a collector of the parasitic LNPN) and a source connected to the ground voltage Vss (i.e., an emitter of the parasitic LNPN), these configurations may not provide a desirable current gain because of presence of a parasitic bipolar transistor Q 3 having an extended base width (see FIG. 4F). This can lead to poor ESD protection.
[0013] Other techniques for improving ESD protection for a salicidation MOS transistor are shown FIGS. 5A, 5B, 6 A and 6 B. In FIG. 5A, after forming N+ source and drain regions S, D in a substrate P-sub by means of an ion implantation, a part of an insulation film 41 formed on top spaces of the polysilicon gate layer GP and source/drain regions is removed. An opening 42 is then formed, exposing parts of the gate layer GP and the source and drain regions S, D. After a local salicidation using the insulation film as a mask, silicide films 44 are formed on the exposed surfaces of the gate layer and the source/drain regions S, D as shown in FIG. 5B. The configuration shown in FIGS. 5A and 5B can provide base width extension, but may be difficult and/or expensive to manufacture and may not provide desirable high frequency operation due to increased parasitic resistance.
[0014] Referring to FIGS. 6A and 6B, an NMOS transistor is fabricated by forming source and drain regions S, D in a substrate P-sub forming extended diffusion regions S′ and D′ under the source and drain regions S and D by means of a high-energy ion implantation, and then performing a salicidation process. Although the double-diffused salicidation transistor shown in FIG. 6B may have a wider discharge space due to the use of the deep-extended diffusion regions S′ and D′, the transistor may exhibit increased resistance and may require additional process steps for its fabrication. In addition, such a transistor may not have desirable ESD protection.
SUMMARY OF THE INVENTION
[0015] According to some embodiments of the present invention, an output circuit of an integrated circuit device includes first and second MOS transistors including respective spaced apart pairs of source and drain regions in a substrate, arranged such that respective first and second channels of the first and second MOS transistors are laterally displaced with respect to one another. The output circuit further includes an isolation region in the substrate, disposed between the first and second MOS transistors. A first conductor connects the source region of the first MOS transistor to a power supply node. A second conductor connects the drain region of the first MOS transistor to the source region of the second MOS transistor. A third conductor connects the drain region of the second MOS transistor to an external signal pad of the integrated circuit device.
[0016] In some embodiments, a surface of the source region of the first MOS transistor that faces the drain region of the second MOS transistor is smaller than a surface of the source region of the first MOS transistor that faces the drain region of the first MOS transistor. The isolation region may comprise at least one insulating region in the substrate, disposed between the first and second active regions. The isolation region may further comprise a guard region having a higher degree of the same conductivity type of the substrate, disposed between the first and second active regions and connected to the power supply node.
[0017] In further embodiments of the present invention, an output circuit includes a first MOS transistor comprising a first source region in a substrate, a first drain region in the substrate, and a first gate electrode disposed therebetween that controls a channel extending between the first source region and the first drain region. The output circuit further includes a second MOS transistor comprising a second source region in the substrate, a second drain region in the substrate, and a second gate electrode disposed therebetween that controls a channel extending between the second source region and the second drain region, arranged such that the first drain region and the second drain region are angularly disposed at first and second angles with respect to the first source region. An isolation region is disposed in the substrate, between the second drain region and the first source region. A first conductor connects the first source region to a power supply node A second conductor connects the first drain region of the first MOS transistor to the second source region. A third conductor connects the second drain region to an external signal pad of the integrated circuit device.
[0018] In still further embodiments of the present invention, an output circuit comprises an isolation region in a substrate surrounding first and second active regions in the substrate. The circuit further includes a first MOS transistor that comprises a plurality of source regions and a plurality of drain regions in the first active region and respective gate lines on the substrate between respective pairs of adjacent ones of the source and drain regions of the first MOS transistor, the source regions of the first MOS transistor connected to a power supply node. The circuit also includes a second MOS transistor comprising a plurality of source regions and a plurality of drain regions in the second active region and respective gate lines on the substrate between respective pairs of adjacent source and drain regions of the second MOS transistor, the drain regions of the first MOS transistor connected to the source regions of the second MOS transistor and the drain regions of the second MOS transistor connected to an external signal pad of the integrated circuit device.
[0019] The first and second active regions may be arranged in a parallel fashion such that the source regions of the first MOS transistor are positioned opposite the drain regions of the second MOS transistor and the drain regions of the first MOS transistor are positioned opposite the source regions of the second MOS transistor. The sides of the source and drain regions of the first MOS transistor that face the second MOS transistor may be narrower than adjacent sides of the source and drain regions of the first MOS transistor, and sides of the source and drain regions of the second MOS transistor that face the first MOS transistor may be narrower than adjacent sides of the source and drain regions of the second MOS transistor.
[0020] Related fabrication method embodiments are also described.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] [0021]FIGS. 1A and 1B are equivalent circuit diagrams of NMOS and PMOS transistors.
[0022] [0022]FIG. 1C is a sectional view of a MOS transistor fabricated by a salicidation process.
[0023] [0023]FIGS. 2A and 2B are planar and sectional view, respectively, of input/output transistors.
[0024] [0024]FIG. 3 is an equivalent circuit diagram of a conventional output circuit.
[0025] [0025]FIG. 4A is an equivalent circuit diagram of another conventional output circuit.
[0026] [0026]FIGS. 4B and 4C are planar and sectional views, respectively, of a configuration for the circuit of FIG. 4A.
[0027] [0027]FIGS. 4D and 4E are planar and sectional views, respectively, of another configuration for the circuit of FIG. 4A.
[0028] [0028]FIG. 4F is an equivalent circuit diagram showing parasitic bipolar transistors for the configurations of FIGS. 4 B- 4 E.
[0029] [0029]FIGS. 5A and 5B show operations for fabricating an NMOS transistor with a conventional partial salicidation process.
[0030] [0030]FIGS. 6A and 6B show operations for fabricating an NMOS transistor with a conventional ion implantation technique.
[0031] [0031]FIG. 7 is a circuit diagram of a protected output circuit according to some embodiments of the present invention.
[0032] [0032]FIGS. 8 and 9 are planar and sectional views, respectively, of a configuration of a protected output circuit according to some embodiments of the present invention.
[0033] [0033]FIG. 10 is an equivalent circuit diagram of parasitic bipolar transistors present in the structure shown in FIGS. 7 - 9 .
[0034] FIGS. 11 A- 11 C and 12 A- 12 C illustrate output circuits according to various embodiments of the present invention,
DETAILED DESCRIPTION
[0035] The present invention now will be described more fully hereinafter with reference to the accompanying drawings, in which preferred embodiments of the invention are shown. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. In the drawings, the thickness of layers and regions are exaggerated for clarity. Like numbers refer to like elements throughout. It will be understood that when an element such as a layer, region or substrate is referred to as being “on” another element, it can be directly on the other element or intervening elements may also be present. In contrast, when an element is referred to as being “directly on” another element, there are no intervening elements present. Moreover, each embodiment described and illustrated herein includes its complementary conductivity type embodiment as well.
[0036] [0036]FIG. 7 shows an output circuit 11 of an integrated circuit device 700 according to embodiments of the present invention, illustrating discharge paths between an external signal pad PAD of the integrated circuit 700 and a power supply voltage node VDD, and between the external signal pad PAD and a power supply ground voltage node VSS. The output circuit includes first and second NMOS transistors N 1 , N 2 connected in series with a PMOS transistor P 1 between a power supply voltage node VDD and a power supply ground node VSS. The output circuit is driven by signals PG, NG applied to respective gate electrodes of the PMOS transistor P 1 and the NMOS transistor N 2 , which responsively drive the external signal pad PAD of the integrated circuit device 700 .
[0037] When a positive transient voltage is present between the external signal pad PAD and the power supply voltage node VDD, the positive transient may be discharged to the power supply voltage node VDD through a discharge path PDp including a forward-biased P+/N junction at the source of the PMOS transistor P 1 . When a negative transient voltage is present between the signal pad PAD and the power supply voltage node VDD, the negative transient may be discharged through two paths, including a primary discharge path through a forward-biased N+/P junction between the drain of the NMOS transistor N 1 and the substrate of the integrated circuit 700 , and a secondary discharge path PDn through a power protection circuit 60 connected between the power supply voltage VDD and the ground voltage VSS.
[0038] When a positive transient voltage is present between the signal pad PAD and the power supply ground voltage node VSS, the positive transient may be discharged through two paths, including a primary discharge path through a forward-biased P+/N junction of the PMOS transistor P 1 , and a secondary discharge path PSp through the power protection circuit 60 (a discharge path PSp). When a negative voltage transient is present between the signal pad PAD and the power supply ground voltage node VSS, the negative transient may be discharged through a discharge path PSn including a forward-biased N+/P junction between the drain of the NMOS transistor N 1 and the substrate.
[0039] [0039]FIGS. 8 and 9 are plan and sectional views, respectively, of an output circuit according to embodiments the present invention. In particular, FIGS. 8 and 9 illustrate a configuration that may be used to implement the output circuit 11 of FIG. 7. FIG. 9 includes a section of the NMOS transistor N 2 , taken along a line Y 1 -Y 1 ′, and a section of the NMOS transistor N 1 , taken along a line Y 2 -Y 2 ′.
[0040] Referring to FIGS. 8 and 9, NMOS transistors N 1 and N 2 are formed in first and second active regions 71 , 72 , which are separated from each other by first and second field oxide insulation regions FOX. The first active region 71 includes drain regions D 1 , D 2 , and source regions S 1 , S 2 , S 3 . Gate electrodes 73 , 74 , 75 , 76 are disposed between adjacent source and drain regions. The second active region 72 includes drain regions D 3 , D 4 , D 5 and source regions S 4 , S 5 , with gate electrodes 73 ′, 74 ′, 75 ′, 76 ′ disposed between adjacent source and drain regions. The drain regions D 1 , D 2 of the NMOS transistor N 1 are connected to an external signal pad PAD through conductive layers (or lines) 77 , 78 , and the source regions S 4 , S 5 of the NMOS transistor N 2 are connected to the power supply ground voltage node VSS through conductive layers (or lines) 79 . The gate electrodes 73 , 74 , 75 , 76 of the NMOS transistor N 1 are connected to a power supply voltage node VDD, and the gate electrodes 73 ′, 74 ′, 75 ′, 76 ′ of the NMOS transistor N 2 are connected to an input signal node NG. The gates of the NMOS transistors N 1 , N 2 may be formed, for example, by a salicidation process.
[0041] The source regions S 1 , S 2 , S 3 of the first NMOS transistor N 1 are connected to the drain regions D 3 , D 4 , D 5 of the second NMOS transistor 72 through conductive layers 81 , 82 , 83 . Avoiding connection of these regions through a common diffusion region can help improve ESD protection. For the illustrated embodiments, smaller (narrower) faces of the source regions S 1 , S 2 , S 3 of the first NMOS transistor N 1 and the drain regions D 3 , D 4 , D 5 of the second NMOS transistor N 2 face one another, which can also reduce the effect of a parasitic NPN transistor associated with these structures. As shown, a P-type (P+) guard ring GD may surround the insulation regions FOX and may be connected the power supply ground node VSS. Such a P-type guard ring GD can further reduce the effect of the parasitic bipolar transistor, as the guard ring GD can decrease base modulation of the parasitic bipolar transistor.
[0042] As shown in FIG. 9, parasitic NPN bipolar transistors Q 1 , Q 2 , Q 3 , Q 4 are associated with the transistors N 1 , N 2 . A base-emitter voltage of the parasitic transistor Q 1 is VDD (Vin-0.6)-Vth, where Vth is a threshold voltage of the transistor N 1 . As the base to emitter voltage of the transistor Q 1 is higher than a turn-on voltage of the parasitic NPN transistor, increasing base current for forward conduction may not cause the parasitic NPN bipolar transistor to be activated.
[0043] [0043]FIG. 10 shows an equivalent circuit for the structure of FIG. 9, including the parasitic transistors Q 1 , Q 2 illustrated in FIG. 9, along with an additional parasitic bipolar transistor Q′ that includes a collector and emitter coupled to the signal pad PAD and the power supply ground voltage node VSS, respectively. The gain the transistor Q′ may be lower than that of the parasitic transistor Q 3 shown in FIG. 4F, because the opposing faces of the drain regions, D 1 and D 2 , connected to the external signal pad PAD, and the source regions, S 4 and S 5 , connected to the power supply ground node VSS, can be made narrower than in the conventional configuration of FIGS. 4 D-F. In contrast to the structure in FIG. 4D, the paths between these faces are angularly displaced from, i.e., not collinear with, the channels of the transistors N 1 , N 2 (in the illustrated embodiment, the paths between these opposing faces are perpendicular to the channels of the transistors N 1 , N 2 ). Interposing the P-type guard ring GD between the source and drain regions of the first and second transistors N 1 , N 2 can further reduce the gain of the parasitic bipolar transistor Q′.
[0044] Operations for fabrication the circuit of FIGS. 8 and 9 will now be described. Referring to FIG. 9, a field oxide layer FOX is formed on the P-type substrate 900 , defining the first and second active regions 71 , 72 . Next, a gate oxide film (not shown) is formed on the active regions 71 , 72 . A conductive material layer, e.g., a doped polycrystalline silicon layer, is then formed on the substrate 900 , and then patterned to form the gate electrodes 73 , 74 , 75 , 76 of the first transistor N 1 and the gate electrodes 73 ′, 74 ′, 75 ′, 76 ′ of the second transistor N 2 .
[0045] N-type impurities are then implanted into the first and second active regions 71 , 72 to form the source and drain regions, S 1 , S 2 , S 3 , S 4 , S 5 , D 1 , D 2 , D 3 , D 4 , D 5 , using the gate electrodes 73 , 74 , 75 , 76 , 73 ′, 74 ′, 75 ′, 76 ′ and the field oxide regions FOX as a mask. The guard ring GD may be formed in the substrate 900 around the first and second active regions 71 , 72 , by, for example, implanting P-type impurities into the substrate 900 . After forming an inter-layer isolation film on the structure with the first and second transistors, N 1 and N 2 , the conductors 77 , 78 , 79 , 80 , 81 , 83 , 83 are formed on the insulation films. The conductors 77 , 78 , 79 , 80 , 81 , 83 , 83 are electrically connected to the source and drain regions, S 1 , S 2 , S 3 , S 4 , S 5 and D 1 , D 2 , D 3 , D 4 , D 5 and the guard ring GD through contact holes penetrating the inter-layer isolation films.
[0046] As shown in FIGS. 11A, 11B and 11 C, the gate electrodes of the transistors N 1 , N 2 may be connected in a number of different ways. For example, as an alternative to the connection shown in FIG. 11A, the gate electrodes of both transistors N 1 can be coupled to the signal input node, as shown in FIG. 11B, or coupled to different signal input nodes NG 1 , NG 2 , as shown in FIG. 11C.
[0047] It will be appreciated that the present application is also applicable to providing ESD protection between an external signal pad PAD and a power supply voltage node VDD, as shown in FIGS. 12A, 12B and 12 C. In these embodiments of the present invention, structures complementary to those in FIGS. 8 and 9 (in terms of conductivity type) may be used for PMOS transistors P 1 , P 2 . As shown in FIG. 12A, the gate electrode of the transistor P 1 may be connected to an input signal node PG, with the gate electrode of the transistor P 2 being connected to a power supply ground node VSS or a reference voltage node Vref. In other embodiments, gate electrodes of both transistors P 1 , P 2 can be connected to an input signal node PG, as shown in FIG. 12B, or to separate input signal nodes PG 1 , PG 2 , as shown in FIG. 12C. It will be further understood that the present invention is also applicable to MOS transistors with gates formed by non-salicidation processes, as activation of a horizontal bipolar loop can be restrained by forming double-diffused sources and drains in an isolated diffusion region.
[0048] In the drawings and specification, there have been disclosed typical preferred embodiments of the invention and, although specific terms are employed, they are used in a generic and descriptive sense only and not for purposes of limitation, the scope of the invention being set forth in the following claims. | An output circuit of an integrated circuit device includes first and second MOS transistors including respective spaced apart pairs of source and drain regions in a substrate, arranged such that respective first and second channels of the first and second MOS transistors are laterally displaced with respect to one another. The output circuit further includes an isolation region in the substrate, disposed between the first and second MOS transistors. A first conductor connects the source region of the first MOS transistor to a power supply node. A second conductor connects the drain region of the first MOS transistor to the source region of the second MOS transistor. A third conductor connects the drain region of the second MOS transistor to an external signal pad of the integrated circuit device. The isolation region may comprise first and second insulation regions surrounding respective ones of the first and second MOS transistors, and a guard ring surrounding and separating the insulation regions. | 7 |
BACKGROUND OF THE INVENTION
[0001] This disclosure relates to a suspension system for a multi-axle vehicle, and more particularly to providing a system, method, and control logic for implementing air suspension control for at least one axle on a trailer. More particularly, the disclosure is directed to a method that alters the axle air suspension pressure partially exhausting or removing air from air suspension bags to reduce tire wear when maneuvering at low speeds. The disclosure precludes a driver of the vehicle from reducing air pressure from the axle suspension above a predetermined speed, and thereby prevents overloaded conditions.
[0002] Federal regulation, namely Title 49 of the Code of Federal Regulations, Section 393.207, states that “the air suspension exhaust controls must not have the capability to exhaust air from the suspension system of one axle of a two-axle air suspension trailer unless the controls are either located on the trailer, or the power unit and trailer combination are not capable of traveling at a speed greater than ten miles per hour while the air is exhausted from the suspension system.”
[0003] One proposed solution is outlined in U.S. Pat. No. 5,052,713, the disclosure of which is incorporated herein by reference. The '713 patent is directed to a vehicle suspension system such as used in multi-axle tractor-trailers and other multi-axle vehicles. When maneuvering a trailer in a confined area such as a loading dock, torque is exerted on the trailer frame. One solution to the torque issue is to remove the load from all but one axle. The '713 patent teaches that air should be exhausted from the air bags on all but one axle in order to improve maneuverability at low speeds or during tight turns. Moreover, and per the federal regulation, the load must be redistributed to the multiple axles once the tight turn maneuvering is complete. Otherwise, the potential exists that a single axle may be overloaded, since the load has not been shifted to multiple axles. The overloading could result in potential damage to the trailer frame or dynamic loading encountered by the vehicle.
[0004] Although the '713 patent provides one solution, there are some downsides to this methodology and system. First, there is risk of damage to the air bags when all air is exhausted therefrom. The air bags may be pinched.
[0005] It is also important to note that the trailer will always be pivoting off the front axle, whether loaded or unloaded. It becomes important, therefore, that the system maintains the front axle with more pressure than the rear axle. That is, it is not just a question of unloading the rear axle, but assuring that the front axle has greater pressure than the rear axle.
[0006] There is also an issue of tire chattering that occurs when all of the pneumatic pressure is exhausted from one axle of the suspension system. Thus, there is a desire to prevent full exhaustion of the air suspension so that the tires associated with the axle are pushed to the ground.
[0007] Still another consideration relates to refilling the air bag. As will be appreciated, once maneuvering at low speeds is complete it becomes important to quickly re-distribute the load over the multiple axles. Known arrangements take as long as thirty (30) to forty (40) seconds to refill the exhausted air suspension. Unfortunately, in that time frame, the vehicle can be up to speed and the load has not been adequately re-distributed.
[0008] Yet another issue is that the air that supplies this system is obtained from the same reservoirs that are associated with the brake system.
[0009] There is also a potential advantage of using existing systems and components.
[0010] Thus, a need exists for an improved system that adds additional benefits in an economical, efficient manner.
SUMMARY OF THE INVENTION
[0011] An improved system and process for controlling vehicle loading on a multi-axle vehicle is provided.
[0012] The process for controlling the vehicle includes reducing pressure in a first axle suspension system when maneuvering the vehicle at predetermined slow speeds. Pressure is kept in the first axle pneumatic suspension system at the predetermined slow speed, and likewise a different pressure is kept in a second axle pneumatic suspension system at the predetermined slow speed. In one embodiment, keeping the pressure includes maintaining a first predetermined pressure at the slow speed, and a second predetermined pressure is maintained in a second axle of the pneumatic suspension system.
[0013] In a preferred arrangement, the second predetermined pressure is greater than the first predetermined pressure, and more preferably, the first predetermined pressure is on the order of 10 psi.
[0014] A pressure reducing step is dependent on the vehicle speed being ten miles per hour or less, and the process includes restoring air pressure upon vehicle speed exceeding the predetermined value.
[0015] The process advantageously uses an anti-lock brake system controller that is modified to include these control functions.
[0016] The air pressure restoring step uses a valve, such as a relay valve, to enable high flow rates to refill the pneumatic suspension system.
[0017] The system includes a reservoir of pressurized air, a leveling valve receiving pressurized air from the reservoir, a valve selectively delivering air to the air suspension assembly, and a controller monitors speed of the vehicle and permits air to be selectively reduced to a predetermined pressure once a predetermined speed is reached.
[0018] A primary benefit of the invention is the improved maneuverability of the vehicle at low speeds.
[0019] Another benefit relates to less torque being imposed on the frame, as well as reduced wear on the tires.
[0020] Still another benefit resides in less pinching of the air bags and the desired need to allow the air bags to keep their shape.
[0021] Yet another benefit relates to the improved re-inflation or quicker restoration of air pressure in the suspension system.
[0022] A further benefit is associated with conserving air in the overall system.
[0023] A still further benefit resides in the ability to integrate the process and system with an existing ABS system and controller.
[0024] Still other benefits and advantages of the disclosure will become apparent to those skilled in the art upon reading and understanding the following detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
[0025] FIG. 1 is a schematic of the preferred logic associated with the present disclosure.
[0026] FIG. 2 is a schematic of a first preferred embodiment of the present disclosure.
[0027] FIG. 3 is a schematic representation of a second preferred embodiment.
[0028] FIG. 4 is a schematic representation of a third preferred embodiment.
[0029] FIG. 5 is a schematic illustrating a fourth preferred arrangement.
[0030] FIG. 6 shows a schematic of a suspension circuit for a fifth preferred embodiment.
[0031] FIG. 7 schematically illustrates a sixth preferred embodiment.
[0032] FIG. 8 is yet another schematic of a seventh preferred embodiment.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0033] Turning first to FIG. 1 , a trailer suspension dump valve (TSDV) is referenced for a semi-trailer (not shown) equipped with axle air suspensions in which air can be partially exhausted from air bags to reduce tire wear and improve vehicle maneuvering at slow speeds. This disclosure prevents the driver of the vehicle from removing air from the suspension of an axle above a predetermined speed, e.g., ten (10) miles per hour, using modified software incorporated into a conventionally available ABS brake controller. The system and method also reduce air bag pressure while preventing exhaustion of all air to atmosphere. The disclosure also advantageously improves the fill rate of the air bags once the slow speed maneuvering is completed and the vehicle then exceeds the predetermined speed.
[0034] Thus, as schematically illustrated, either original or restored air bag pressure is provided in the suspension system as noted by reference numeral 100 . The operator actuates a switch, for example on the dashboard of the vehicle, the vehicle speed is monitored through a signal provided to an electronic control unit (ECU) of the vehicle, and the same information is input to the trailer antilock brake system (ABS or TABS) controller as typically found on a vehicle. In addition, a warning lamp may be provided to indicate whether or not the switch for activating the trailer suspension dump has been actuated. Thus, with the switch either activated to reduce air pressure in the rear axle air bags, or alternatively switched to a position set to restore air bag pressure, it is evident that the switch must be set to a desired position, and the speed of the vehicle monitored. The modified software incorporated into an existing ABS controller then indicates if the vehicle speed is greater than ten (10) miles per hour, whereby air must be automatically restored to the rear axle air bags. Only when the vehicle speed reaches some predetermined threshold, e.g., less than eight (8) to ten (10) miles per hour, will the software permit air bag pressure to be reduced. Thus, wheel speed is already provided to the ABS controller and can interact with the modified software to achieve these functions.
[0035] FIG. 2 shows a first preferred arrangement, in which front air bags 110 , 112 are associated with a first or front axle 114 . Similarly, the suspension system includes air bags 116 , 118 are associated with a second or rear axle 120 . Pressurized air is provided from reservoir 130 which is maintained at a desired pressure by a compressor (not shown), as is well known in the art. All of the details of a conventional trailer antilock brake system (TABS) are not shown in order to reduce complexity, simplify the drawings, and for purposes of brevity. However, TABS controller 132 is represented as being in communication with the air reservoir 130 to provide rapid pulsed or controlled brake application in an anti-lock braking event, again, as is well known in the industry. As will also be appreciated, suitable signals are provided from the wheels to the controller 132 so that vehicle speed can be monitored.
[0036] The air suspension system, and particularly, the individual air bags 110 , 112 , 116 , 118 of the multiple axles are supplied with pressurized air from the reservoir 130 . That is, a pressure protection valve 134 is located downstream of the reservoir and protects system air pressure and maintains a constant specified pre-set pressure below that of the reservoir 130 if a downstream failure in the suspension system occurs. The pressure protection valve 134 would then prevent system pressure loss for the remaining pneumatic systems of the vehicle. The reduced pressure air is directly supplied to a pressure limiting valve assembly which includes a normally closed, three-way solenoid valve 140 , and particularly a supply or inlet port 142 thereof. Delivery port 144 of the solenoid valve provides a control signal to an inversion valve 150 , and particularly control port 152 thereof. Supply pressure from the protection valve 134 is also provided to a leveling valve 160 , and specifically to the supply port 162 of the inversion valve. There are two delivery ports on the leveling valve. The first delivery port 164 supplying pressure to the air bags 110 , 112 associated with the front axle. The second delivery port 166 communicates with a supply port 154 of the inversion valve 150 so that when a control signal is provided by the solenoid valve, pressure continues downstream to delivery port 156 that communicates with relay valve 170 . More particularly, the delivered pressure from the inversion valve 150 communicates with a control port 172 of the relay valve so that supply port 174 , that receives pressurized air from the pressure protection valve 134 , is selectively delivered to first and second delivery ports 176 , 178 and thus delivers pressurized air to the air bags 116 , 118 associated with the rear axle.
[0037] Line 200 is representative of a signal received from a switch mounted on a dash of a vehicle cab. Line 200 communicates with a relay 202 which is also adapted to receive a signal from the TABS controller 132 indicative of a predetermined speed. When the TABS controller sees a velocity of less than ten (10) miles per hour, for example, and where a signal is received through line 200 , then an appropriate signal is sent along line 204 that communicates with the solenoid valve 140 . The solenoid is then energized and allows the solenoid valve to deliver air from port 144 to a control port 152 of the inversion valve and thereby cause the inversion valve to exhaust its delivery through a pressure protection valve 210 associated with the inversion valve. The pressure protection valve 210 is designed to only partially exhaust the pressurized air, i.e., so that the air suspension reaches a predetermined level, for example 10 psi, and causes relay valve 170 to exhaust the suspension associated with the rear axle to this same level. Thus, the pressure protection valve does not allow the suspension associated with the rear axle to fully or substantially exhaust and instead keeps pressure in the rear suspension system. When the signal through line 204 is removed, such as if the dash switch is de-actuated, or if the velocity goes above the predetermined speed (e.g. ten (10) miles per hour), the system then reverts back to a non-dump operation.
[0038] In the non-dump operation, leveling valve 160 delivers air to the supply port of the inversion valve. Since line 204 is not actuated, and thus the solenoid is not energized, control port 152 does not receive air pressure from the solenoid valve and thus the inversion valve delivers air to the control port of the relay valve 170 , which, in turn, causes the relay valve to deliver air pressure to the suspension air bags 116 , 118 .
[0039] A second preferred embodiment is shown in FIG. 3 and for consistency and ease of illustration, like components will be identified by like reference numerals, while new components are identified by new reference numerals. In this arrangement, the solenoid valve 140 still communicates with the pressure protection valve 134 via supply port 142 . As in the first embodiment, the leveling valve 160 still supplies the inversion valve 150 and particularly at the supply port 154 thereof. Here, however, a pressure reducing valve 211 (not a pressure protection valve as in FIG. 2 ) also receives pressure from the protection valve 134 at port 212 . During a non-dump operation, the pressure from protection valve 134 proceeds through the reducing valve 211 to its outlet port 214 , where it communicates with one side of a double-check valve 220 , and namely port 222 . However, higher pressure provided from the inversion valve 150 , and namely from port 156 during a non-dump operation, communicates with port 224 of the two-way valve. The double-check valve 220 , thus delivers the higher pressure from the inversion valve to the control port of relay valve 170 . This causes the relay valve to deliver air to the air bags 116 , 118 of the suspension associated with the second axle. Thus, the leveling valve 160 delivers air to the supply port of the inversion valve 150 . Since there is no delivery from the solenoid valve 140 , since no signal is present on line 204 , the inversion valve 150 delivers air to the double-check valve. This port 224 of the double-check valve sees higher pressure than the air that has proceeded through the reducing valve 211 and which communicates with the other port 222 of the double-check valve. Accordingly, the double-check valve will deliver the higher pressure from the inversion valve to the relay valve and bring the air bags up to pressure.
[0040] When a vehicle operator actuates the rear axle air dump switch, a signal is provided on line 200 . In addition, once the TABS controller 132 detects a velocity of less than ten (10) miles per hour, for example, a signal is then provided on line 204 to the solenoid valve 140 . This signal causes the solenoid to energize and, in response, delivers air from port 144 to the control port 152 of the inversion valve, thereby causing the inversion valve to exhaust to atmosphere. As a result, pressurized air does not reach port 224 of the double-check valve. Consequently, the double-check valve still receives a reduced level of air pressure from reducing valve 211 (on the order of 10 psi) which proceeds through the double-check valve and is delivered to control port 172 of the relay valve. This causes the relay valve to exhaust the suspension to the same pressure level, i.e., on the order of 10 psi. Once the signal from the dash switch is removed so there is no signal on line 200 , or once the velocity exceeds ten (10) miles per hour so that no signal is present to relay 202 , the solenoid valve 144 is no longer energized due to the absence of a signal on line 204 and the system reverts to the non-dump operation described above.
[0041] A double-check valve arrangement is maintained in the third embodiment of FIG. 4 , however, a slightly different schematic is used to supply port 222 thereof. More specifically, a synchronization valve 240 is added to the circuit. The synchronization valve includes a supply port 242 that is delivered pressure at a reduced level from delivery port 214 of the pressure reducing valve 211 . In the non-dump operation, when no control signal is present on line 204 to energize the solenoid valve 140 , there is no delivery from port 144 to the inversion valve. An additional branch line communicates between the delivery port 144 of the solenoid valve and port 244 of the synchronization valve. Thus, if there is no delivery from port 144 of the solenoid valve, the synchronization valve likewise will not deliver air through port 246 to port 222 of the double-check valve. Consequently, the double-check valve will deliver the higher pressure from port 156 of the inversion valve to the control port 172 of the relay valve. This causes the relay valve to deliver air to the air bags of the suspension.
[0042] The operation of the system of FIG. 4 will now be described with reference to the dump operation. As noted previously, the vehicle operator actuates a switch to provide a signal along line 200 indicating that the vehicle operator would like to remove some air from one of the axles in order to improve maneuverability. If the TABS controller recognizes a velocity of less than ten ( 10 ) mile per hour, for example, then a signal from the auxiliary connector 202 is provided along line 204 to the solenoid valve. The solenoid is then energized and delivers air to inversion valve 150 , namely port 152 . This control air causes the inversion valve to exhaust to atmosphere. In addition, the solenoid valve will deliver air to the control port 244 when the solenoid is energized. This causes the synchronization valve to deliver 10 psi pressurized air, or another desired pressure level, from the reducing valve 211 to supply port 242 , which then communicates with port 246 of the synchronization valve. In this manner, port 222 of the double-check valve 220 delivers the 10 psi air pressure to the relay valve control port 172 . This, in turn, causes the relay valve to exhaust the air suspension associated with the rear axle to 10 psi. As will be appreciated, when the signal from the auxiliary connector 202 is removed, or the velocity goes above ten (10) miles per hour, the system then automatically reverts back to the non-dump operation described above.
[0043] Still another solution for selectively dumping a portion of the air from one of the axles to improve maneuverability is shown in FIG. 5 . This embodiment still includes the solenoid valve and inversion valve of the pressure limiting valve assembly, and also the relay valve arrangement for quickly refilling the air bags, but additionally employs a limiting valve 250 . Particularly, a supply port 252 of the limiting valve communicates with the delivery port of the pressure protection valve 134 . In addition, the delivery port 156 of inversion valve 150 does not directly communicate with the relay valve 70 . Instead, the inversion valve delivers air pressure to control port 254 of the limiting valve. Delivery port 256 of the limiting valve communicates with the control port of the relay valve 170 .
[0044] In a non-dump operation, the leveling valve delivers air to the supply port 154 of the inversion valve. Since there is no delivery from port 144 of the solenoid valve, the inversion valve delivers air to the control port 254 of the limiting valve 250 . With the limiting valve 250 being supplied with pressure from the pressure protection valve 134 , and being controlled by the inversion valve 150 , the limiting valve 250 will deliver full pressure to control port 172 of the relay valve. In this manner, the relay valve will deliver pressurized air from the protection valve 134 via ports 174 to ports 176 , 178 that communicate with the air bags.
[0045] If the vehicle operator desires to improve maneuverability of the vehicle at low speeds, a signal is provided to line 200 , for example by actuating the switch on the dash. Only when the relay 202 also receives a signal from the TABS controller acknowledging that the vehicle velocity is below a predetermined threshold, for example ten (10) miles per hour, is a signal then provided along line 204 to energize the solenoid. Energizing the solenoid of valve 140 delivers air from port 144 to the control port 152 of the inversion valve. This causes the inversion valve to exhaust air to atmosphere. Thus, no pressure signal is provided to control port 254 of the limiting valve. Without such a control signal, the limiting valve will only deliver 10 psi to the control port 172 of the relay valve. As will be appreciated, this causes the relay valve to partially exhaust the suspension air bags 116 , 118 to a predetermined level, on the order of 10 psi. When the signal 200 to the relay (by de-actuating the switch) is removed or if the vehicle velocity increases above ten (10) miles per hour (as monitored by the TABS controller), then the system solution of FIG. 5 reverts to the non-dump operation.
[0046] The use of single check valves in a suspension circuit in conjunction with the solenoid valve, inversion valve, and relay valve, is illustrated in FIG. 6 as another potential solution. Here, single check valves 260 , 262 are provided with interconnecting lines 264 , 266 to provide selective one-way communication between the first/front and second/rear sets of suspension air bags. Thus, check valve 260 and line 264 interconnect the air bags on one side of the vehicle, while line 266 in conjunction with check valve 262 interconnects the air bags on the other side of the vehicle between the rear and front suspension assemblies. The check valves are arranged to permit communication from the rear suspension air bags to the front suspension air bags. The single check valves will not, however, transfer from the front suspension to the rear suspension. In this latter direction, the check valves act as a buffer against pressure spikes, for example chuck holes, bumps, etc., and preclude an air transfer from the front suspension air bags 110 , 112 to the respective rear suspension air bags 116 , 118 when in the dump mode.
[0047] Thus, typical non-dump operation of the schematic solution of FIG. 6 is as follows. The leveling valve 160 delivers air to the supply port 154 of the inversion valve 150 . Since the solenoid is not energized in valve 140 , there is no signal provided to control port 152 of the inversion valve. Consequently, the inversion valve delivers air from port 156 to the control port 172 of the relay valve 170 . This, in turn, delivers air through ports 176 , 178 to the air bags 116 , 118 of the rear axle of the suspension arrangement.
[0048] When the vehicle operator would like to convert to the dump operation, the switch is activated to provide a signal along line 200 to relay 202 . Once the TABS controller 132 indicates that vehicle speed has been reduced to a velocity under ten (10) miles per hour, a signal is then provided on line 204 to energize the solenoid. This, in turn, provides a control signal from port 144 of the solenoid valve to the control port 152 of the inversion valve and the inversion valve then exhausts air that it would have otherwise delivered to the relay valve through the pressure protection valve 210 . The pressure protection valve is designed to only partially exhaust the air to a certain predetermined level, for example 10 psi, and thereby cause the relay valve to exhaust the rear suspension 116 , 118 to the same level. In this manner, the rear suspension air bags are maintained at a reduced level relative to the air bags of the front suspension, and the check valves maintain this pressure differential.
[0049] An alternate solution using a commercially available R-12 relay valve available from Bendix Commercial Vehicle Systems LLC, the assignee of the present application, is shown in FIG. 7 . More particularly, the leveling valve 160 delivers air directly to supply port 174 of the relay valve. In addition, the pressure protection valve 134 delivers pressurized air directly to the supply ports of the solenoid valve 140 and the inversion valve 150 . The solenoid valve delivery port 144 still communicates with the control port 152 of the inversion valve. Thus, in the non-dump operation when the solenoid is not energized, the inversion valve delivers air from its supply port 154 to its delivery port 156 and thereby provides a control pressure signal to control port 172 of the relay valve. This causes the relay valve to deliver air from its supply port 174 to the dual delivery ports 176 , 178 associated with air bags 116 , 118 , respectively, of the rear suspension.
[0050] Presuming that the vehicle operator actuates a switch for improved maneuverability at low speeds, a signal is then present at line 200 . As discussed previously, it is also necessary for the TABS controller 132 to indicate to the relay 202 that the vehicle speed has dropped below a certain level, namely less than ten (10) miles per hour. Only then is a signal provided in line 204 to energize the solenoid and thereby deliver air from port 156 to the control port 152 of the inversion valve. This causes the inversion valve to exhaust its delivery through the single check valve 270 (not a pressure protection valve as in FIG. 2 or a pressure reducing valve as in Figures and 4 ). Importantly, though, is the fact that the check valve will limit the exhaust when it reaches a predetermined level, for example approximately 10 psi, which causes the relay valve 170 to partially exhaust the suspension to the same level, again on the order of 10 psi. When the signal from the auxiliary connector is removed in line 200 , or if the TABS controller indicates that vehicle velocity has risen above ten (10) miles per hour, there is no signal at 204 thus de-energizing the solenoid and the system reverts to non-dump operation.
[0051] FIG. 8 illustrates a modified SR valve in an arrangement that bears some similarities to that described with respect to FIG. 7 . Here, however, there is no pressure protection or check valve associated with the inversion valve as was the case with the valve 270 in the FIG. 7 solution. Instead, leveling valve 160 receives supply pressure at port 162 from the pressure protection valve 134 . It delivers air pressure from the leveling valve to the front suspension air bags 110 , 112 and to a modified SR valve 280 , having a supply port 282 . In addition, the pressure protection valve 134 is plumbed directly to the supply ports 142 of the solenoid valve and 154 of the inversion valve. In the non-dump operation, i.e., when there is no signal in line 204 to energize the solenoid, there is consequently no delivery from port 144 to the control port 152 of the inversion valve. Consequently, the inversion valve 150 delivers air from delivery port 156 to control port 284 of the modified SR valve so that air at supply port 282 is delivered from ports 286 , 288 to respective air bags 116 , 118 of the rear air suspension.
[0052] In the dump operation, the solenoid in solenoid valve 140 is energized and provides the air pressure signal to control port 152 of the inversion valve. This, of course, means that the vehicle operator has actuated the system switch, and that the vehicle is also operating at a velocity of less than ten (10) miles per hour. The control signal of port 152 causes the inversion valve to exhaust its delivery to atmosphere. This, in turn, means that there is no pressure signal at control port 284 and the modified SR valve then partially exhausts its delivery until an internal mechanism stops the exhaust at the predetermined threshold, for example on the order of 10 psi. Likewise, when the vehicle operator returns the switch to the non-dump position, or if the velocity goes above ten (10) miles per hour, the solenoid is de-energized and thus the system reverts to the non-dump operation described above.
[0053] In summary, this disclosure provides semi-trailers equipped with axle suspensions to partially exhaust air from the air suspension or air bags to reduce tire wear when maneuvering at slow speeds. The disclosure prevents the driver of the vehicle from exhausting air from the suspension of an axle when the vehicle is operating at a speed above ten (10) miles per hour. This is accomplished by modifying the software capabilities of a conventional TABS brake controller.
[0054] The disclosure also provides a method for reducing air bag pressure while importantly preventing exhausting of all of the air to the atmosphere, i.e., only partially exhausting the air. By not reducing the air suspension pressure to atmosphere, the fill time associated with refilling is reduced.
[0055] Moreover, by using the relay valve, higher flow rates are enabled to the air bags, which also shortens the time to restore the pressure to the suspension. Stated another way, the relay valve improves system responsiveness since flow rate is not limited by the constraints of the leveling valve.
[0056] The attendant risk of damaging air bags is also eliminated by preventing exhausting of the air to atmosphere. Moreover, these arrangements also assure that more pressure is provided to the front suspension assembly than the rear axle during the dump operation.
[0057] The invention has been described with reference to the preferred embodiment. Modifications and alterations will occur to others upon reading and understanding this specification. It is intended to include all such modifications and alterations in so far as they come within the scope of the appended claims or the equivalents thereof. | A system and process for controlling vehicle loading on a multi-axle vehicle and improving maneuverability is disclosed. The system includes a reservoir of pressurized air and associated leveling valve that uses a relay valve to improve refill times when the vehicle returns from a dump mode operation to normal operation. The process reduces pressure in one or more of the axles when maneuvering the vehicle at predetermined slow speeds and maintaining that first predetermined pressure while the other axle(s) is at a greater pressure than the first axle. By preventing complete exhaustion of pressure from the suspension system, restoring air pressure is attained more quickly. Also, use of a relay valve enables higher flow rates to improve the refill time of the pneumatic suspension system after the dump operation. | 1 |
TECHNICAL FIELD
The present invention relates to a rear wheel steering control system that can change the toe angles of rear wheels of a vehicle.
BACKGROUND OF THE INVENTION
It has been proposed to fit a four-wheeled vehicle with a rear wheel steering control system in addition to a more conventional front wheel steering system for the purpose of improving the driving stability of the vehicle. Typically, in association with each rear wheel is provided an electric linear actuator having an output rod that can be selectively extended and retracted so that the two rear wheels may be steered individually. See Japanese patent laid open publication No. 9-030438, for instance.
The linear actuator may be advantageously incorporated into one of the lateral arms that form a part of the wheel suspension system of the corresponding rear wheel. In such a case, changing the toe angle of the rear wheel is effected by changing the length of such a lateral arm. Therefore, as the toe angle of the rear wheel is changed, the geometry of the wheel, in particular the tread of the rear wheels, changes at the times of bump and rebound, and this may adversely affect the ride quality of the vehicle.
BRIEF SUMMARY OF THE INVENTION
In view of such problems of the prior art, a primary object of the present invention is to provide a rear wheel steering control system that can improve the ride quality of a vehicle fitted with a rear wheel steering control system.
A second object of the present invention is to provide a rear wheel steering control system which is highly simple and compact in structure.
According to the present invention, such objects can be at least partly accomplished by providing a rear wheel steering control system for a vehicle, comprising; an actuator for changing a toe angle of each rear wheel; a rear wheel steering control unit for activating the actuator according to a prescribed plan; and a road condition estimating unit for estimating a state of a road surface over which the vehicle is traveling; wherein the rear wheel steering control unit forces the toe angle of each rear wheel to a substantially neutral position or a slightly toe-in position when the road condition estimating unit has detected a rough road surface.
Thereby, when the vehicle is traveling over a rough road surface, the actuator is forced to the neutral position, and the rear wheels are brought to a neutral position so that the changes in the wheel geometry (tread and/or alignment) of the rear wheels at the time of a bump or a rebound can be avoided. Therefore, the ride quality of a vehicle equipped with the rear wheel steering control system is favorably maintained even when the vehicle is traveling over a road surface, and the rear wheels undergo large vertical displacements.
According to a preferred embodiment of the present invention, the vehicle is additionally fitted with an unsprung mass control unit, and the road condition estimating unit is enabled to determine the state of road condition from a manipulated variable of the unsprung mass control unit. Thereby, the state of the road surface can be accurately determined in a simple and inexpensive manner.
According to a particularly preferred embodiment of the present invention, the unsprung mass control system forms a part of a damper control system including a variable damping force damper, and is configured to supply a control current corresponding to a product of a stroke and a stroke speed of the damper to the variable damping force damper. The variable damping force damper may consist of a telescopic damper using MRF (magneto-rheological fluid) for the working fluid thereof.
BRIEF DESCRIPTION OF THE DRAWINGS
Now the present invention is described in the following with reference to the appended drawings, in which:
FIG. 1 is a diagram of a four-wheeled vehicle incorporated with a rear wheel steering control system embodying the present invention;
FIG. 2 is a fragmentary perspective view of a left rear wheel suspension system;
FIG. 3 is a vertical sectional view of a linear electric actuator of the rear wheel steering control system;
FIG. 4 is a block diagram of an essential part of an ECU used in the rear wheel steering control system; and
FIG. 5 is a flowchart showing the rear wheel steering control process of the illustrated embodiment.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
A preferred embodiment of the rear wheel steering control system of the present invention is described in the following with reference to FIG. 1 . In FIG. 1 , some of the components thereof are associated with each wheel, and such component parts are denoted with suffices fl, fr, rl and rr to indicate with which wheel the particular component is associated. For instance, a front left wheel is denoted with 3 fl , a front right wheel with 3 fr , a rear left wheel with 3 rl and rear right wheel with 3 rr . When a particular component is collectively referred to, it may be denoted with the corresponding numeral without the suffix. For instance, the wheels of the vehicle may be referred to simply as 3 depending on the situation.
Referring to FIG. 1 , the illustrated vehicle V has a vehicle body 1 which has four wheels 3 each fitted with a pneumatic tire 2 . Each wheel 3 is rotatably supported by a knuckle 7 which is in turn supported by wheel suspension system 5 including suspension arms, a spring and a variable damping force damper 4 . The variable damper 4 essentially consists of a telescopic piston and cylinder, and uses MRF (magneto-rheological fluid) for the working fluid thereof. By controlling a magnetic fluid valve incorporated in a piston of the damper 4 , the damping force for the given stroke speed thereof can be changed both quickly and continuously.
The vehicle V is fitted with a front wheel steering system 9 that allows the right and left front wheels 3 fl and 3 fr to be steered by turning a steering wheel 19 with the aid of a rack and pinion gear mechanism, and a rear wheel steering control system 6 that allows each rear wheel 3 rl , 3 rr to be steered individually by a corresponding electric actuator 8 l , 8 r provided in association with the corresponding rear wheel. Each electric actuator 8 consists of a linear actuator that has a housing attached to a part of the vehicle body 1 and an output rod connected to the knuckle 7 and configured to extend and retract according to an electric current supplied thereto.
The rear wheel steering control system 6 allows the toe-in and toe-out of the rear wheels 3 to be changes by steering the rear wheels in a mutually symmetric relationship in a corresponding direction, and the rear wheels to be steered by a same steering angle by extending the output rod of one of the actuators and retracting the output rod of the other actuator in an opposite direction by a same stroke.
The various onboard control systems including the dampers 4 rear wheel steering control system 6 are centrally controlled by an onboard ECU (electronic control unit) 20 which essentially consists of a microcomputer incorporated with ROM, RAM, interface circuits, input and output interfaces and drivers, and is connected to various sensors (which will be described hereinafter), the dampers 4 and the electric actuators 8 via a communication line such as CAN (controlled area network).
The vehicle V is provided with a steering angle sensor 10 for detecting a steering angle of the steering wheel 19 , a vehicle speed sensor 11 for detecting a traveling speed of the vehicle, a lateral G sensor 12 for detecting a lateral acceleration of the vehicle, a fore-and-aft acceleration sensor 13 for detecting a fore-and-aft acceleration of the vehicle and a yaw rate sensor 14 for detecting a yaw rate of the vehicle which are arranged in appropriate parts of the vehicle V. The vehicle V is additionally provided with a vertical G sensor 15 attached to a part of each wheel house for detecting a vertical acceleration of the corresponding part of the vehicle and a stroke sensor 16 for detecting a vertical stroke of each wheel. Each electric actuator 8 is provided with a position sensor (linear encoder) 17 for detecting the output stroke of the actuator, and the knuckle 7 of each rear wheel 3 rl , 3 rr carries an unsprung mass G sensor 18 for detecting the vertical acceleration of the knuckle 7 (unsprung mass acceleration).
FIG. 2 is a perspective view of a left rear wheel suspension system 5 rl . The right rear wheel suspension system 5 rr can be given as a mirror image of the left rear wheel suspension system 5 rl.
As shown in FIG. 2 , this rear suspension system 5 rl is of a double wishbone type, and comprises a knuckle 7 rotatably supporting the rear wheel 3 rl , an upper and lower arms 21 and 22 joining the knuckle 7 to the vehicle body in a vertically moveable manner, an electric actuator 8 l joining the knuckle 7 to the vehicle body so as to allow the toe angle of the rear wheel 3 rl to be varied, a suspension spring 4 a resiliently supporting the rear wheel to the vehicle body and a damper 5 to apply a damping force to the vertical movement of the knuckle 7 .
The upper arm 21 is attached to a part of the vehicle body 1 via a rubber bush joint 23 at the base end thereof and to an upper part of the knuckle 7 via a ball joint 25 , and the lower arm 22 is attached to a part of the vehicle body 1 via a rubber bush joint 24 at the base end thereof and to a lower part of the knuckle 7 via a ball joint 26 . The housing of the electric actuator 8 l is attached to the vehicle body 1 via a rubber bush joint 27 , and the output rod of the electric actuator 8 l is connected to a rear part of the knuckle 7 via a rubber bush joint 28 . The damper 4 is connected to the vehicle body 1 via a rubber bush not shown in the drawings at the upper end thereof, and to an upper part of the knuckle 7 via a rubber bush joint 29 at the lower end thereof.
Thus, when the output rod of the electric actuator 8 l is extended, the rear part of the knuckle 7 moves laterally outward so that a toe-in movement of the rear wheel 3 rl is effected. Conversely, when the output rod of the electric actuator 8 l is retracted, the rear part of the knuckle 7 moves laterally inward so that a toe-out movement of the rear wheel 3 rl is effected.
FIG. 3 is a vertical sectional view of the electric actuator 8 l of the illustrated embodiment. As shown in FIG. 3 , the electric actuator 8 l comprises a first housing 30 a integrally formed with the rubber bush joint (vehicle body) 27 , a second housing 30 b connected to the first housing 27 by a plurality of threaded bolts 31 and forming a whole housing 30 jointly with the first housing 20 a and an output rod 32 extending out of the second housing 30 b and having the rubber bush joint (knuckle) 28 formed at the free end thereof. The first housing 30 a receives therein a brushless DC motor 34 serving as a power source and fixedly attached to the first housing 30 a by using threaded bolts 35 . The second housing 30 b receives therein a planetary gear type reduction gear unit 36 , an elastic coupling 37 and a feed screw mechanism 38 using a trapezoidal thread.
When the DC motor 34 is actuated, the rotation of the output shaft 34 a thereof is reduced in speed by the reduction gear unit 36 , and is then converted into a linear motion of the output rod 32 by the feed screw mechanism 38 .
The position sensor 17 provided on the outer periphery of the second housing 30 b essentially consists of a magnet piece 41 fixedly attached to the output rod 32 by a threaded bolt 39 and a differential transformer 43 received in a sensor housing 42 which is in turn attached to the second housing 30 b so as to oppose the magnet piece 41 . The differential transformer 43 includes a primary winding and a pair of secondary windings, and a differential voltage produced between the secondary windings provides a measure of a linear displacement of the output rod 32 .
FIG. 4 is a block diagram of an essential part of the ECU 20 used in the illustrated embodiment. The ECU 20 includes a damping force control unit 52 for controlling the damping action of the dampers 4 , a rear wheel steering control unit 53 for controlling the steering action of the electric actuators 8 , an input interface 51 interfacing the various sensors 10 - 18 with the damping force control unit 52 and rear wheel steering control unit 53 , and an output interface 54 interfacing the damping force control unit 52 and rear wheel steering control unit 53 with the respective actuators.
The damping force control unit 52 comprises an attitude control unit 55 , a first control current setting unit 56 , an unsprung mass control unit 57 , a second control current setting unit 58 and a target current selecting unit 59 . The attitude control unit 55 comprises a skyhook control unit 60 , a roll control unit 61 and a pitch control unit 62 which produce a skyhook control target value Dsh, a roll control target value Dr and a pitch control target value Dp, respectively, according to the detection signals of the various sensors 10 - 16 . The first control current setting unit 56 selects one of the three control target values Dsh, Dr and Dp which is the same in sign as the stroke speed of the damper 4 and largest in absolute value as the first target damping force Dtgt1, and looks up a first control current Itb1 from a prescribed first control current map for the given first target damping force Dtgt1 and stroke speed obtained from the stroke sensor 16 .
The unsprung mass control unit 57 computes an unsprung mass control target value Dw for each damper 4 according to the vehicle speed obtained from the vehicle speed sensor 11 and stroke position obtained from the stroke sensor 16 . The second control current setting unit 58 sets the unsprung mass control target value Dw as the second target damping force Dtgt2, and looks up a second control current Itb2 from a prescribed second control current map for the given second target damping force Dtgt2 and stroke speed obtained from the stroke sensor 16 .
The skyhook control unit 60 is configured to control the oscillation of the sprung mass, and is effective in suppressing the resonant oscillation of the sprung mass which is about 1 Hz, but is relatively ineffective in suppressing the resonant oscillation of the unsprung mass which is about 10 Hz. In the unsprung mass control, when the damper stroke and stroke speed are high, an unsprung mass control current computed by multiplying a prescribed constant, the damper stroke speed and damper stroke is used instead of the skyhook control current (or added to the target current value required by the skyhook control) to provide the final target current for the damper. As a result, independently of the skyhook control, the resonant oscillation of the unsprung mass in a frequency range around 10 Hz can be effectively suppressed. For more details of the unsprung mass control, reference may be made to Japanese patent laid open publication No. 2006-321259, and U.S. Pat. No. 7,406,371.
The target current selecting unit 59 compares the obtained first control current Itb1 and second control current Itb2 with each other, and sets one of them having a greater absolute value as the target current Itgt, and supplies a drive current corresponding to the target current Itgt to the magnetic fluid valve of each damper 4 so that a desired damping control may be accomplished.
The rear wheel steering control unit 53 comprises a road condition estimating unit 63 , a target steering angle setting unit 64 , a target displacement setting unit 65 and a drive current setting unit 66 . The road condition estimating unit 63 estimates the state of the road surface on which the vehicle is traveling according to the unsprung mass control target value Dw computed by the unsprung mass control unit 57 , and forwards the estimated state of the road surface to the target steering angle setting unit 64 . The target steering angle setting unit 64 then determines a rear wheel target steering angle according to the detection signals of the steering angle sensor 10 and yaw rate sensor 14 and the estimated state of the road surface. The target displacement setting unit 65 determines a target displacement of the electric actuator 8 according to the difference between the target rear wheel steering angle and actual rear wheel steering angle obtained from the output of the position sensor 17 . The drive current setting unit 66 supplies a drive current for the electric actuator 8 according to the target displacement.
The mode of operation of the illustrated embodiment is described in the following. When the operation of the vehicle V has started, the ECU 20 executes the damping force control and a rear wheel steering control at a prescribed control interval (2 ms, for instance).
The damping control is executed by the damping force control unit 52 . Upon determining the operating condition of the vehicle according to the detection signals of the various sensors 10 - 16 , the damping force control unit 52 computes a skyhook control target value Dsh, a roll control target value Dr and a pitch control target value Dp for each wheel according to the determined operating condition of the vehicle V. The first control current setting unit 56 selects one of these target values which has the same sign as the stroke speed of the damper and the largest absolute value as a first target damping force Dtgt1, and looks up a first target current map to determine a first control current Itb1 according to the first target damping force Dtgt1 and the stroke speed of the damper 4 . The unsprung mass control unit 57 computes an unsprung mass control target value Dw according to the vehicle speed and stroke position of the damper 4 . The second control current setting unit 58 then sets the unsprung mass control target value Dw as a second target damping force Dtgt2, and looks up a second target current map to determine a second control current Itb2 according to the second target damping force Dtgt2 and the stroke speed of the damper 4 . The target current selecting unit 59 selects one of the first target damping force Dtgt1 and second target damping force Dtgt2 which is greater in absolute value as a target current Itgt which is supplied to the damper 4 for controlling the damping force thereof.
The rear wheel steering control of the illustrated embodiment is described in the following with reference to the flowchart of FIG. 5 . The rear wheel steering control is performed on each of the rear wheels 3 rr and 3 rl in a similar manner, and the following description is limited to that for the left rear wheel 3 rl for the convenience of description.
The ECU 20 executes the rear wheel steering control illustrated in the flowchart of FIG. 5 concurrently with the damping control described above. The road condition estimating unit 63 determines if the absolute value of the unsprung mass control target value Dw forwarded from the unsprung mass control unit 57 at a regular control interval is greater than a prescribed threshold value S 1 in step ST 1 . If the determination result is Yes, a current cumulative value I n is computed by adding “1” to the previous cumulative value I n-1 in step ST 2 . If the determination result is No, the current cumulative value I n is computed by subtracting “1” from the previous cumulative value I n-1 in step ST 3 . In the latter case, it is determined if the current cumulative value I n is smaller than zero in step ST 4 . If it is the case, the current cumulative value I n is set to zero in step ST 5 . Thus, the minimum value of the current cumulative value I n is zero owing to the process executed in steps ST 4 and ST 5 .
Following steps ST 2 , ST 4 or ST 5 , the road condition estimating unit 63 determines if the current cumulative value I n is greater than a second threshold value S 2 in step ST 6 . If the determination result of this step is Yes or if the vehicle V is traveling over a rough road surface, the absolute value of unsprung mass control target value |Dw| increases owing to the need to control the vibration of the unsprung mass. Therefore, the state of the road surface can be evaluated by determining if the current cumulative value I n has exceeded the second threshold value S 2 . The determination result of the road condition estimating unit 63 is forwarded to the estimated road surface signal to the target steering angle setting unit 64 .
When the estimated road surface signal indicates a rough road surface, the target steering angle setting unit 64 set the rear wheel target steering angle to zero in step ST 7 . Each actuator 8 is configured such that the rear wheel steering angle is zero when the actuator is in a neutral state without being extended or retracted. The target displacement setting unit 65 and a drive current setting unit 66 control each electric actuator 8 so that the rear steering angle is maintained at zero. As a result, when the vehicle is traveling over a rough a rough road surface, each electric actuator 8 is maintained in a neutral position so that the impairment of the ride quality which may be otherwise caused by the changes in the tread of the vehicle at the time bump and rebound conditions owing to the extension or retraction of the electric actuator 8 may be avoided.
When the estimated road surface signal does not indicate a rough road surface, the rear wheel target steering angle is set in a normal way according to the detection signals of the steering angle sensor 10 and yaw rate sensor 14 in step ST 8 . The target displacement setting unit 65 and a drive current setting unit 66 control each electric actuator 8 so that the actual rear wheel steering angle agrees with the target rear wheel steering angle. When the vehicle is not traveling over a rough road surface, extending or retracting the electric actuator 8 does not cause changes in the tread at the time of bump or rebound, and the actuation of the electric actuator 8 does not impair the ride quality.
As a slightly modified embodiment of the present invention, the rear wheel target steering angle may be set to a slightly toe-in angle by extending the electric actuator 8 . By forcing the rear wheel target steering angle to a slightly toe-in angle from a normally controlled value, the changes in the tread at the time of the bump and rebound can be controlled, and the ride quality of the vehicle is prevented from being impaired.
Although the present invention has been described in terms of preferred embodiments thereof, it is obvious to a person skilled in the art that various alterations and modifications are possible without departing from the scope of the present invention which is set forth in the appended claims. For instance, the state of the road surface was estimated from the unsprung mass target value Dw in the foregoing embodiment, but may also be estimated from other data such as the detection signal of the vertical G sensor 15 and image information obtained by a camera.
The contents of the original Japanese patent application on which the Paris Convention priority claim is made for the present application, as well as the contents of any publications mentioned in this disclosure, are incorporated in this application by reference. | In a rear wheel steering control system for a vehicle, a rear wheel steering control unit ( 53 ) forces the toe angle of each rear wheel ( 3 rl, 3 rr ) to a substantially neutral position or a slightly toe-in position when a road condition estimating unit ( 63 ) has detected a rough road surface. Thereby, when the vehicle is traveling over a rough road surface, the actuator is forced to the neutral position, and the rear wheels are brought to a neutral position so that the changes in the wheel geometry (tread and/or alignment) of the rear wheels at the time of a bump or a rebound can be avoided. Therefore, the ride quality of a vehicle equipped with the rear wheel steering control system is favorably maintained even when the vehicle is traveling over a road surface, and the rear wheels undergo large vertical displacements. | 1 |
BACKGROUND OF THE INVENTION
This invention relates to framing and in particular to metal framing primarily but not exclusively for use as window framing.
At present, metal window framing is commonly made of steel or aluminium. For a variety of commercial reasons, mild steel is usually preferred but this material has the disadvantage that it normally requires a surface finish to prevent corrosion in use and to achieve a satisfactory appearance. Furthermore, the exposed surfaces of such framing often require regular maintenance, for example, painting. Stainless steel overcomes the corrosion and maintenance problems and has a satisfactory appearance for many installations but is is expensive to produce and difficult to work during the framing manufacture.
SUMMARY OF THE INVENTION
It is the object of the present invention to provide framing members suitable for framing which is inexpensive in manufacture, is easily installed and, subsequently, requires little or no maintenance, and which also can be produced with a variety of visible surface finishes as required.
In accordance with the invention a framing member for metal framing comprises three elongated tubular elements lying in parallel relationship, each such element having at least one plane surface adjacent to a similar plane surface of another element, resilient sealing strips located between each pair of adjacent plane surfaces, and transverse fasteners securing the elements together in two or more places along their lengths, the fastener elements being adapted to exert pressure on the sealing strips.
With such a construction, the elements can be made from different materials, so that those visible when the member is installed can be made of an expensive material or decoratively finished, and those elements which are hidden can be made of a cheaper material, e.g. mild steel.
In one form of the invention, each fastener comprises two pins, each such pin passing through two elements so that the pin ends lie in opposed juxtaposition within a common element of the three and are secured together by a collet which engages grooves in the pin ends.
In another form of the invention two of the elements have expanding head rivets or welded studs projecting from their plane surfaces which pass through holes in the adjacent plane surfaces of the third element, which lie between the two first-mentioned elements, so that the protruding ends of the rivets lie in juxtaposition within the third element. After the elements assembly is compressed to apply compression to the sealing strips, the adjacent rivet ends are permanently joined by welding, holes being provided in a wall of the third element to allow access to the rivets or studs for the welding operation.
The invention also includes a plurality of the framing members assembled and joined together to form a framing.
BRIEF DESCRIPTION OF THE DRAWINGS
Embodiments of the invention are illustrated in the accompanying drawings wherein:
FIG. 1a shows a modification of the member of FIG. 1,
FIG. 1 shows a cross-section of a framing member according to the invention,
FIG. 2a shows a modified collet usable in the invention,
FIG. 2 shows a side view of a short length of the member shown in FIG. 1,
FIG. 3 shows an elevation of a connecting piece employed in the construction of the member,
FIG. 4 shows, in elevation, the parts employed in joining the ends of two members at right angles,
FIG. 5 shows, in elevation, the parts employed in producing a T-joint between two members,
FIG. 6 shows, in elevation, the parts employed in producing a joint between members crossing at right angles,
FIG. 7 shows a cross-section of another framing member with an alternative form of fastener,
FIG. 8 shows a side view, partly cut away, of a short length of the same member, and
FIG. 9 shows a sectioned elevation of a further form of corner joint between members meeting at right angles.
DETAILED DESCRIPTION OF THE INVENTION
The framing members hereinafter to be described with reference to FIGS. 1-3 can be assembled together by joints exemplified in FIGS. 4, 5 and 6 to provide a variety of framing structures, glazed or unglazed, for windows, partitions, barriers, doors, vehicle body members, greenhouses, prefabricated buildings, racking and other purposes. The exterior profile of each member is dependent upon its intended purposes and what glazing or other sheet material, hinge parts, catches, or locks, if any, is to be secured or to be mounted on the framing. However, each member basically comprises three parallel tubes fastened together, each of which has one plane surface adjacent a plane surface of another element with resilient sealing strips between each pair of adjacent surfaces. To simplify an understanding of the invention, in the embodiment about to be described each tube is of a plain rectangular section as best shown in FIG. 1. One of the tubes is made of mild steel and forms a main structural part of the member and a base for the attachment of the other two secondary tubes 2,3 one on each of two of its opposed walls. The secondary tubes, which are normally visible when the finished member is installed in a building may be made of a variety of materials for example, stainless steel, plastics, or mild steel with any selected surface finish or coating as may be required to present a pleasing appearance, and/or protection against corrosion. The secondary tubes are of a pronounced "flat" shape, that is to say, two of their opposite walls are considerably wider than the other two so that the secondary tubes overhang the sides of the main tube which lie adjacent the surrounding masonry or timber when the frame is installed and the edges of the frame glazing respectively.
A sealing fillet, 4, 5 of resilient material, e.g. a rubber or plastics composition, is placed between each secondary tube and the main tube walls. One of the fillets may extend beyond one of the side faces 6 or 7 of the main tube 1, as shown at 4a in FIG. 1a, and be enlarged to form a grooved housing to receive one edge of a glass sheet enclosed by the frame. This glass sheet can be secured in position by a glazing strip of tubular channel, or other suitable section lying against the main tube, and abutting both the housing part of the fillet and an overhanging surface of one or another of the secondary tubes, so as to compress the housing part and ensure tightly sealed retention of the glass. If the frame is intended for use as a hinged casement or to surround such a hinged casement either or both fillets may be extended beyond the main tube and upon an overhanging part of a secondary tube to form a weather seal or seals between the casement and its surrounding frame and hinged parts may be secured to an appropriate end of the secondary tube.
The three tubes of each framing element are secured together by transverse fasteners located in at least two spaced-apart positions intermediate the tube ends. In the majority of cases, it is sufficient to provide two fasteners on each framing element at positions near the opposite tube ends.
In the form shown in the drawings each fastener comprises two coaxial pins, 8, 9 and a collet 10 connecting the pins and located within the main tube 1. The pins have head portions 8a, 9a, lying within the secondary tubes 2, 3 and are located in key-hole slots 12, 13 formed in the inner face of the secondary tubes. The shanks are passed through registering holes 14, 15 in the juxtaposed main tube walls so that the shank ends face each other within the main tube. The collet 10 is box-shaped and has opposed walls, 16, 17 which are slotted at 18, 19 to slide into annular grooves 20, 21 in the pin shanks and prevent endwise movement of the pins. During assembly pressure is applied to the assembly of the tubes compressing the sealing fillets and causing the pins of each fastener to be brought into position to receive the collet. As a result the pins are subjected to tension after the pressure is removed thus preventing subsequent movement or dislodgement of the collet and ensuring a tight seal between the fillets and the tube walls.
Alternatively, as shown at 10a in FIG. 2a, the collets may be U-shaped and made from spring steel in such a manner that, by the use of a tool, they can be expanded and then fitted to the pins. When the tool is removed, the collets contract thus pulling the pins together and clamping the tubes onto the sealing fillets.
Access holes are formed in the tube to allow the pins and collets to be installed during the assembly stage. These holes, e.g. 22, are subsequently sealed with suitable plugs. The plugs sealing the access holes in the main tubes to the collets may include a headed screw bearing on the collet to further assist in its retention and carrying sealing washers which, by the reaction pressure of the screws, are pressed firmly against the inside of the access holes. The screw heads may be adapted to form retaining means for a glazing bead or strip. Alternatively and/or additionally, bonding materials such as cold setting or thermosetting adhesive may be used to attach the secondary tubes to the main tubes.
In another form of fastener (FIGS. 7 and 8) the pins 8, 9 are replaced by studs 108, 109 welded to the secondary tubes or by rivets with expanding heads passed through holes in the secondary tubes 102, 103 and secured in the case of rivets by expanding the rivet heads. In place of the collet 10, the rivet or stud ends are permanently joined, after the tubes have been squeezed together to compress the fillets, by welding, as at 110, the welding tool being passed through the access hole 122 in the main tube 101.
Corner joints between the members forming adjacent sides of the frame may be secured by clamp devices as shown in FIG. 4 engaging the two main tubes of the respective members. The ends of the members are mitred and an L-shaped 20a is fitted into the hollow ends of the two main tubes 1a, 1b, so that its limbs 21a and 22a form end plugs within the tubes. One of the limbs 22a is drilled at 23 to receive a pin extending transversely through a pre-formed hole 24 in a wall of its enclosing main tube, 1b, each of the secondary tubes having a clearance hole appropriately positioned in its wall adjacent the main tube for the protruding ends of the pin, and one of the secondary tubes having an access aperture provided to allow the pin to be inserted. The pin is a push fit in the limb of the L-shaped member and the access aperture is plugged after the pin has been installed. The other limb 21a of the member is bored longitudinally at 25 to receive a clamping screw (not shown) which engages a threaded hole 26 in a block 27 also pinned within the respective main tube 1a beyond the member limb 21a. The clamping screw, which is accessible through the end of the main tube 1b in which it lies, is tightened by an appropriate tool, for example a screwdriver or Allen key, to pull up the joint and render it rigid. The L-shaped member can be made from a moulded plastics material and include fins extending outwardly from its surfaces across the corner of the L and which are trapped between the mitred ends of the elements to form joint seals. Since the clamped device lies wholly within the main tubes it is hidden when the element is installed in a window aperature. A metal, rubber or plastics plug may be fitted to the tool access hole.
As shown in FIG. 5, a similar form of clamping device may be used to secure a joint where the end of one member is secured to an intermediate part of a second member, for example where a glazing bar joins a frame upright. In such a clamping device the L-shaped member is replaced by a T-shaped member 30 having two outwardly extending limbs 31, 32 forming the cross-parts of the T extending along the main tube 1c of the second element and the upright limb 33 of the T which also receives the clamping screw is housed within the end of the main tube 1d of the first-mentioned member. The joint is pulled up by the clamping screw (not shown) which engages a threaded hole 34 in a block 35 pinned in the main tube 1d of the first-mentioned member and is accessible through a suitable aperature 36 in the main tube of the second member. To ensure a close fitting joint, the end of the first member is mitred to present an arrow head 37 which closely fits a corresponding V-shaped notch 38 cut in the second member. The T-shaped member may be made of a plastics material and its surfaces finned to form sealing fillets which are compressed between the mitred end of the first member and the notch edges in the other member to prevent the ingress of water at the joint.
Where members meet to form an X-joint the arrangement shown in FIG. 6 is employed. In such a joint the ends of the main tubes 1e, 1f of two co-axial horizontal members are mitred to form arrow heads 40, 41 to mate within notches 42, 43 cut in the opposite sides of the main tube 1g of a vertical member. A bar 44 lying partly within each of the tubes 1e, 1f extends transversely through the bore of the tube 1g. One end of the bar is pinned within the tube 1e by a pin passing through registering holes 45, 46 in the tube and bar, respectively, the part of the bar lying within the tube 1f is slotted longitudinally, the slot 47 slidably housing a square plug 48 pinned within the tube 1f through registering holes 49, 50. A screw housed in a threaded hole 51, extending from the end of the slot to the nearer end of the bar is rotated to bear on the plug so drawing the tubes 1e, 1f tightly into contact with the tube 1g. As in the previously described joints the bar member may be made of a plastics material with finned surfaces to form sealing fillets between the mating edges of the tubes.
An alternative method of forming a joint between connected framing members as shown in FIG. 9 utilizes a shaped block 60 of metal or, more preferably, thermoplastics material located within the spaces formed by the communicating interiors of the main tubes 1g, 1j of the meeting members at the joint, the block thus forming a rigid plug within the members. The members are pressed together after the block is inserted and the block is then rivetted in place as at 61 through the walls of the main tubes which are not visible when the framing is installed. If thermoplastics material is employed in constructing the block it can be further anchored by heat treating the joint to heat seal the block to the adjacent tube surfaces. A similar procedure may be employed for joining the secondary tubes of members and in such joints rivetting is avoided by piercing holes in the tube walls for the block material to flow therein and form anchoring protrusions when heated. | Framing members of metal are produced from three tubular elements in parallel adjacent relationship held together by transverse fasteners. Sealing strips are located between the adjacent surfaces of the elements and subjected to pressure by the fasteners. In one form of the invention each of the fasteners comprises two pins, each of which passes through two elements so that the pin ends lie in opposed juxtaposition within a common element of the three and are secured together by collets. Alternatively, welded studs are employed. The members are joined together to form a frame by internal blocks shaped to suit the shape of the joint, e.g. angle or tee, and secured by clamping screws or riveting. | 4 |
RELATED APPLICATION
This application is a continuation in part of application Ser. No. 09/017,195, filed Feb. 2, 1998.
This patent application is a continuation-in-part of U.S. patent application Ser. No. 09/017,195 to Haller et al. Entitled “Implantable Drug Infusion Device Having a Safety Valve Assembly”, the disclosure of which is hereby incorporated by reference herein in its entirety.
FIELD OF THE INVENTION
The present invention relates to the field of implantable medical devices, and more particularly to a safety valve assembly for an implantable drug infusion device.
BACKGROUND OF THE INVENTION
Implantable drug infusion devices are used to provide patients with a constant and long term dosage or infusion of a drug or any other therapeutic agent. Essentially such device may be categorized as either active or passive.
Active drug or programmable infusion devices feature a pump or a metering system to deliver the drug into the patient's system. An example of such an active drug infusion device currently available is the Medtronic SynchroMed programmable pump. Such pumps typically include a drug reservoir, a peristaltic pump to pump out the drug from the reservoir, and a catheter port to transport the pumped out drug from the reservoir via the pump to a patient's anatomy. Such devices also typically include a battery to power the pump as well as an electronic module to control the flow rate of the pump. The Medtronic SynchroMed pump further includes an antenna to permit the remote programming of the pump.
Passive drug infusion devices, in contrast, do not feature a pump, but rather rely upon a pressurized drug reservoir to deliver the drug. Thus such devices tend to be both smaller as well as cheaper as compared to active devices. An example of such a device includes the Medtronic IsoMed™. This device delivers the drug into the patient through the force provided by a pressurized reservoir. In particular, this reservoir is pressurized with a drug to between 20-40 psi through a syringe capable of delivering the fluid between 35-55 psi.
Regardless of whether the device is an active or passive drug infusion device, the overriding concern for all drug infusion devices is to ensure patient safety. This includes, among many other things, that only the exact intended amount of drug is delivered to the patient. Thus, one drawback to active devices which feature pumps that are not normally closed, such as those seen in U.S. Pat. Nos. 5,277,556; 5,224,843 and 5,219,278, is that if the device malfunctions or changes occur in the fluid pathway, then more drug than intended may reach the patient. Similar risks are inherent in passive devices which, should the flow regulator fail or the pressure reservoir be over pressurized, may lead to more drug than intended to reach the patient.
Thus there is a need for a drug infusion system which features a safety valve assembly which will provide an additional margin of safety to the patient.
SUMMARY OF THE INVENTION
The present invention is an implantable beneficial agent or drug infusion device, which features a unique safety valve assembly. In one embodiment of the present invention, the safety valve assembly comprises a seal which is normally closed and opens only upon being a deflectable or moveable member to which the seal is attached being electrically, magnetically or electro-magnetically activated. The valve assembly is preferably small in size and made of corrosion resistant materials. The valve assembly may be employed in either a passive or an active drug or beneficial agent implantable infusion system.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram of the present invention.
FIG. 2A is a side view of one embodiment of a safety valve assembly of the present invention in a closed position.
FIG. 2B shows the safety valve assembly of FIG. 2B in an open position, thereby permitting fluid egress from the reservoir thereof.
FIGS. 3A and 3B disclose an alternative embodiment of the safety valve assembly of the present invention.
FIG. 4 is a schematic diagram of one embodiment of a driver circuit employed to control a piezo-electric embodiment of the lower member shown in FIGS. 2A and 2B which recollects energy stored on a piezo-electric substrate when the voltage on the piezo-electric member is switched off.
FIG. 5 is a timing diagram of the operation of the driver circuit shown in FIG. 4 .
FIG. 6 depicts an alternative driver circuit for a piezo-electric member.
FIG. 7 is a timing diagram of the circuit shown in FIG. 6 .
The Figures are not necessarily to scale.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
This patent application hereby incorporates by reference into the specification hereof each of the following patent applications, each in its respective entirety: (1) U.S. patent application Ser. No. 09/239,306 to Haller et al. entitled “System for Locating Implantable Medical Device”; (2) U.S. patent application Ser. No. 09/014,196 to Haller et al. entitled “Implantable Drug Infusion Device Having a Flow Regulator”; and (3) U.S. patent application Ser. No. 09/017,194 to Haller et al. entitled Implantable Drug Infusion Device Having an Improved Valve”.
FIG. 1 shows a block diagram of the present invention. As seen, such a system 1 comprises a reservoir 2 , safety valve assembly 3 assembly, pump 4 , electronic controls 10 , battery 11 , telemetry assembly 12 and outlet catheter 5 . Outlet catheter may be of any model desired and suited to the patient's requirements. Safety valve 3 assembly is coupled to the reservoir and also to pump 4 . Pump may be of any suitable design, including a roller-type pump as found in the SynchroMed™ or a micro-machined pump, for example. Pump 4 is coupled, in turn to outlet catheter 5 , such that fluid form reservoir 2 may be pumped through safety valve assembly and out to outlet catheter. Pump is controlled by electronic controls 10 . These controls include, among other devices, an efficient circuit to drive the membranes used in safety valve assembly 3 . The device may be refilled through injection port 5 through the use of a needle 6 as is well known. This refill procedure may be further enhanced through the use of the system as described in the above-referenced '306 patent application to Haller. Surrounding all components of the implantable pump other than the outlet catheter is a hermetic closure 13 as is well known in the art. The device may further feature, if desired, a flow regulator, such as that shown in the '196 patent application to Haller.
FIG. 2A shows a cross-sectional view of one embodiment of safety valve assembly 3 of the present invention in the closed position. Hermetically sealed collapsible reservoir 2 is filled with a desired beneficial agent, drug, medicament, or pharmaceutical such as by needle refilling through a reservoir fill port and self-sealing septum know in the art. Examples of the beneficial agents, drugs, medicaments, and pharmaceuticals that may be infused into a patient's body with the device and method of the present invention include, but are not limited to, gene therapeutic agents, protein- or peptide-based drugs, morphine, BACLOFEN®, antibiotics, and nerve growth factors.
Bellows 26 form the sidewalls of reservoir 2 , and are preferably formed from titanium in a manner similar to that employed to form the titanium bellows employed, for example, in the MEDTRONIC® SYNCHROMED® infusion system. Of course, materials other than titanium may be employed to form bellows 26 . When formed of titanium, bellows 27 are most preferably about 50 microns to about 75 microns thick.
Propellant 27 is disposed in the volume existing between the outwardly-facing walls of bellows 26 and the inwardly-facing walls of outer walls 28 (within which most of safety valve assembly 3 is disposed). An appropriate formulation of bi-phasic fluorocarbon may be employed as propellant 27 , and may be obtained from 3M Corporation in St. Paul, Minn. Propellant 27 is intended to cause a relatively constant pressure to be exerted against the outwardly-facing walls of bellows 26 when held at a temperature at or near human body temperature (e.g., 35-39 degrees Celsius).
Safety valve assembly 3 further includes deflectable upper member or membrane 20 , seal 22 mounted on or attached to intermediate member or cap 33 / 34 , first substrate 25 , second substrate 14 , deflectable or moveable lower member 21 , and shoulder 19 . Upper membrane 20 is preferably formed of titanium metal and has a thickness ranging between about 25 microns and about 50 microns, but may be thicker (e.g., up to 100 microns) or thinner (e.g., 20 microns). Upper membrane 20 may alternatively be formed of silicone, in which case its thickness would range between about 10 microns and about 20 microns. Upper membrane 20 is preferably 6 to about 15 mm in diameter. Seal 22 most preferably forms an o-ring structure and comprises a deformable material such as silicone rubber, polyimide, TEFLON (PTFE or polytetranfluoroethylene), a polymeric substance, or any other suitable material. Seal 22 preferably has a diameter ranging between 1 and 3 mm, or between about 25 and about 50 microns. Shoulder 19 may be formed of titanium, silicon, or any other suitable material.
Depending on the composition of shoulders 23 / 24 and first substrate 25 , shoulders 23 / 24 may be attached to substrate 25 by connecting means such as brazing, welding, anodic bonding, or silicon fusion bonding, such means being selected on the basis of the materials forming shoulders 23 / 24 and first substrate 25 . Cap 32 / 33 is most preferably about 1 mm in height, about one-half the diameter of seal 22 (e.g., between about 0.5 mm and about 1.5 mm), and most preferably comprises nipple 32 formed of silicon, silicone rubber, or titanium or any other suitable material, and end cap 33 formed of glass, silicon, silicone rubber, or titanium or any other suitable material. The height of intermediate member or cap 32 / 33 is preferably determined by the thicknesses of first substrate 25 and shoulder 19 . Cap 32 / 33 may be glued or otherwise attached to member 31 , or alternatively may form a single piece or component in respect of member 31 or lower member 21 .
Fluid in reservoir 2 exerts a pressure or force F on the top surface of membrane 20 , thereby pushing membrane 20 down, onto and against the upper surface of seal 22 . To aid in preventing the undesired opening of safety valve assembly 3 , it is preferred that membrane 20 , connecting shoulders 23 and 24 , seal 22 , cap 32 / 33 , and deflectable or moveable lower member 21 be configured and cooperate with one another such that membrane 20 is under mechanical tension and stretched over seal 22 , even in the absence of force or pressure provided by fluid disposed in reservoir 2 .
The ends of membrane 20 are attached to shoulders 23 and 24 by any of a number of known connecting means such as brazing, welding, anodic bonding, or silicon fusion bonding, such means being selected on the basis of the materials forming upper membrane 20 and shoulders 23 and 24 . In the closed position of safety valve assembly 3 , the lower surface of seal 22 is pushed down against substrate 25 by upper membrane 20 . Cap 32 / 33 may be formed of two portions, nipple 33 and end cap 34 , or may comprise a single portion. The upper surface of cap 32 / 33 is attached to seal 22 , while the lower surface of cap 32 / 33 is attached to the upper surface of member 31 . Connecting member 31 , in turn, is preferably attached to deflectable or moveable lower member 21 by electrically conductive epoxy 34 or other suitable means.
The ends of connecting member 31 are attached to substrate 14 by any of a number of known connecting means such as brazing, welding, anodic bonding, or silicon fusion bonding, such means being selected on the basis of the materials forming connecting member 31 . Alternatively, connecting member 31 may form a single contiguous piece of material extending laterally away from the edges or perimeter of lower member 21 . The upper surface of lower member 21 is preferably attached to connecting member 31 by means of electrically conductive epoxy, the ends of lower member 21 not being attached to second substrate 14 . Deflectable or moveable lower member 21 is most preferably formed from a suitable piezo-electric or piezo-crystal material such as PZT (lead zirconium titanate) or PMN (lead magnesium niobate). A piezo-electric material is preferred for deflectable or moveable member 21 because piezo-electric materials are capable of undergoing relatively large displacements when subjected to an electric field. Other embodiments of lower member 21 are contemplated in the present invention, however, such as electrostatic, electro-capacitive and solenoid embodiments of lower member 21 , where motion and displacement are imparted to member 21 by means of electric or magnetic fields, or the flow of electrical current.
Integrated circuit 37 is shown as being disposed on the underside of second substrate 14 , and preferably receives electrical power from a battery (not shown in FIG. 2 A). Integrated circuit 37 comprises a driving circuit, which receives electrical power from a battery or other power source and transforms it into a signal appropriate to cause lower member 21 to move upwardly in response to the application of an electrical filed. It is preferred that integrated circuit 37 provide an output voltage ranging between about +80 and +150 Volts. Wire bonds 38 and 39 provide the electrical connections required to permit such an output voltage to be applied across the top and bottom surfaces of lower member 21 . Other electrical connection techniques may be employed than wire bonds to provide the output signal to the lower member including, but not limited to, flextape, solder and the like. Wire bond 39 is most preferably held at ground and electrically connected to electrically conductive epoxy 34 via an electrical connector in feedthrough 36 disposed in second substrate 14 . Alternatively, the top end of the electrical connector in feedthrough 36 may be electrically connected to another type of electrically conductive coating or member disposed on the upper surface of deflectable or moveable lower member 21 , such as an evaporated, vacuum deposited, electrochemically plated or other electrically conductive plating or member. Wire bond 38 is most preferably switched to a voltage ranging between about +80 and +150 Volts when it is desired to move lower member 21 and seal 22 into the open position.
FIG. 2B shows the safety valve assembly of FIG. 2A in the open position, where deflectable or moveable member 21 has moved upwardly in response to an electrical voltage being applied thereacross by integrated circuit 37 . Seal 22 , the underside of which is connected to lower member 21 via cap 32 / 33 , member 31 and glue 34 , has moved upwardly such that the top surface thereof has engaged and pushed up against the underside of membrane 20 to cause membrane 20 to be deflected upwardly. Fluid present in reservoir 2 and residing in intermediate volume 17 (after having passed through membrane passageway 15 ) now flows into exit passageway 35 for eventual delivery to the patient. Via catheter and pump means (not shown). Once the voltage applied across lower member 21 is withdrawn, lower member 21 returns to the position illustrated in FIG. 2 A and further delivery of the fluid contained in reservoir 2 is terminated.
It is an advantage of the present invention that safety valve assembly 3 is maintained in the closed position when power is withdrawn or lost from the implantable medical device within which it is disposed (e.g., the battery thereof becoming depleted below a certain voltage, etc.), when reservoir 2 is overfilled during refilling, or when external factors such as changes in temperature or pressure occur such that reservoir 2 becomes overpressurized.
The various components of safety valve assembly 3 (e.g., member or membrane 20 , seal 22 , lower member 21 , cap 32 / 33 , etc.) may be configured mechanically such that seal 22 cannot be pushed into the open position, and lower member 21 cannot move upwardly sufficiently to cause seal 22 to open, when a nominal output voltage is applied across lower member 21 and when reservoir 2 has been overfilled to the point of excessive fluid pressures having developed within reservoir 2 . That is, the various components of safety valve assembly 3 may be configured such that seal 22 can move into the open position only so long as the pressure or force applied to the upper surface thereof by the fluid contained in reservoir 2 does not exceed a predetermined amount or limit. Such a design prevents the inadvertent and unintended delivery of excessive amounts of the drug contained within reservoir 2 to the patient.
It is contemplated in the present invention that the specific configuration of upper member 20 , lower member 21 , and seal 22 presented in the drawings hereof be modified such that upper membrane 20 is deflected in response to the provision of an output signal thereto while lower membrane 21 and seal 22 remain in relatively fixed positions.
FIGS. 3A and 3B disclose an alternative embodiment of the safety valve assembly of the present invention. Such an embodiment features shape memory alloy membranes as opposed to the piezo-electric membranes disclosed above. This embodiment features a superior membrane 40 and an inferior membrane 41 . Membrane 40 is biased in an upward direction while membrane 41 is biased in a downward direction. The respective biasing strengths of these membranes control membrane 40 to normally close the valve when no energy is provided to membrane 41 . Upon energizing the membrane 41 , however, the shape memory alloy undergoes a reorganization of the crystalline structure. As constructed, this removes the bias to membrane 41 . Membrane 40 will, in turn, overcome the bias provided by membrane 41 and thus move the seal assembly 42 upwardly and away from seal footing 43 mounted on substrate 44 thereby creating a fluid passage from cavity 45 to passageway 50 . As seen, membrane 40 is mounted across shoulder elements 50 and 51 and includes center portion 52 . The shoulder and center portions are preferably constructed of glass. As further seen, membrane 41 is disposed on the downward surface of shoulder and center portion and further mounted to bases 53 and 54 . Bases as well as seal assembly 42 are also constructed from glass. This entire assembly is further mounted to substrate 44 through contacts 60 and 61 . Contacts 60 and 61 are preferably constructed from silicone. Substrate 44 is preferably constructed of glass while footing 43 is constructed of silicone. Membranes are preferably constructed from Nitinol, although other shape memory alloys may also be used. Moreover, the areas of substrate and membranes in contact with any drug or fluid are further preferably coated with diamond or diamondlike carbon so as to inhibit any interactions between the drug or fluid and the materials. Such coatings may be selected according to the particular drug or fluid to be infused, and may include also tantalum or titanium, for example.
Essentially, the operation of this embodiment may be seen in compared FIGS. 3A and 3B. At rest, or when no energy is provided to membranes, the particular bias to membranes causes seal assembly 42 to snugly engage against footing 43 . Once energy is provided to the membranes, the energy or electric current causes the material to heat up and thereby ending the phased transformation, i.e., the crystalline structure is reorganized. Thus seal assembly 42 is caused to disengage against footing 43 and thereby opens a fluid pathway from cavity 45 into passageway 50 . Of course, although in this embodiment a double membrane design is shown, other embodiments may feature a single, biased membrane as well as three or more membranes, depending upon the exact fluid pathway required.
One difficulty with all battery powered implantable devices is that they must operate with as little energy drain as possible. A problem typically associated with prior art piezo-electric membranes is that driver circuits typically dissipated the charge built up after a voltage was applied across the membrane. This, of course, wasted energy, and particularly such built-up charge. Another feature of the present invention is the use of a driver circuit which minimizes the energy used. In. particular, the present invention further features a driver circuit which recollects the stored energy on the piezo when the voltage on the piezo is turned to zero.
FIG. 4 is a schematic diagram of a driver circuit used to control the piezo membrane of the embodiment shown in FIGS. 2A and 2B which recollects the stored energy on the piezo when the voltage on the piezo is turned to zero. FIG. 5 is a timing diagram of the operation of the driver circuit shown in FIG. 4 . Each of these FIGS. will now be described together. As seen, the circuit consists of a 3V power supply, four N-MOS switches with low ohms resistance, 1 P-MOS switch, a storage capacitor and inductor and a piezo membrane. M 1 and M 2 are high voltage devices while M 3 -M 5 are low voltage devices. At its initial condition, all switches are closed except M 5 . In step 1 (with reference also to FIG. 5 ,) M 3 and M 4 are opened and M 5 is closed to thereby charge capacitor C 2 through inductor L 1 . In step 2 , M 2 is opened and M 3 is closed to thereby connecting inductor L 1 to piezo. The current in L 1 is maintained and a voltage is developed on the drain of M 2 , as best illustrated by line 99 in FIG. 5, and a voltage is thereby developed across piezo. Once voltage in piezo (or L 1 ) reaches a maximum level step 3 begins. As seen in this step M 1 is opened and M 2 is closed thereby shorting L 1 and maintaining the charge on piezo. Charge actuates the piezo and may be maintained on the piezo for as long as actuation is desired. In steps 4 , 5 and 6 the process is reversed. In step 4 , M 2 is opened, M 1 is closed thereby discharging the piezo voltage through the inductor. In step 5 M 3 is opened and M 2 is closed and the current through L 1 is flowed through C 2 thereby discharging C 2 . Finally in step 6 , M 5 is opened and M 3 and M 4 are closed, thereby returning to initial conditions. In such a manner the piezo may be driven through a minimal amount of energy. As seen the amount of energy delivered to piezo is determined by the amount of energy delivered to L 1 , which may be determined by the time which elapses between step 1 and step 2 . Of course, if C 1 is not completely charged full, then operation is slightly changed, and in step 2 M 5 opened, M 4 opened and M 3 closed. Thereafter the operation remains as described although in step 5 M 5 is closed. Additional functionality to monitor voltages or current or both and determine the proper timing for closing the switches is not shown, but would be performed in block 10 of FIG. 1, labeled control system.
FIG. 6 depicts an alternative driver circuit for the piezo membrane of FIG. 2 . FIG. 7 is a timing diagram of the circuit shown in FIG. 6 . Each of these FIGS. will now be described together. As seen, this circuit consists of a 3V power supply, a storage capacitor—C 1 , a piezo model capacitor—C 2 , an inductor—L 1 , and four N-MOS switches—M 1 -M 4 . The pulses S 1 -S 3 are 10V square wave pulses created by the pulse generation circuit.
The first step in creating the piezo drive pulse is to charge the storage capacitor, C 1 , to the voltage level of the power supply by closing switches M 1 and M 3 /M 4 . After C 1 is fully charged to the supply voltage, the inductor, L 1 , is charged with current by discharging the stored energy in C 1 . This is done by simultaneously opening M 1 while closing M 2 and keeping M 3 /M 4 closed. Then M 2 is reopened while M 3 /M 4 remains closed to charge the piezo, C 2 , with the stored current. The voltage on C 2 rises to 150V and all switches are opened while the pulse remains high.
After the high pulse on the piezo is finished, M 3 /M 4 is closed to drain the energy from the piezo into the inductor L 1 . After the piezo is drained switch M 2 is closed, while M 3 /M 4 remains closed, to charge C 2 with the energy stored in the inductor L 1 . The cycle begins again with another rising edge on M 1 . The following timing diagram displays the timing sequence for closing of switches M 1 , M 2 , and M 3 /M 4 where time units are in seconds.
Although a specific embodiment of the invention has been disclosed, this is done for purposes of illustration and is not intended to be limiting with regard to the scope of the invention. It is contemplated various substitutions, alterations and/or modifications may be made to the disclosed embodiment without departing from the spirit and scope of the invention. Such modifications may include substituting elements or components which perform substantially the same function in substantially the same way to achieve substantially the same result for those described herein.
In the claims, means-plus-function clauses are intended to cover the structures described herein as performing the recited function and not only structural equivalents but also equivalent structures. Thus, although a nail and a screw may not be structural equivalents in that a nail employs a cylindrical surface to secure wooden parts together, whereas a screw employs a helical surface, in the environment of fastening wooden parts a nail and a screw are equivalent structures.
All patents and printed publication referenced hereinabove are hereby incorporated by reference herein, each in its respective entirety. | An implantable beneficial agent infusion device featuring a unique safety valve assembly is disclosed. In one embodiment of the present invention, a seal in the safety valve assembly is normally closed and only opens upon a deflectable or moveable member to which the seal is attached being electrically, magnetically or electromagnetically activated. The valve assembly is preferably small in size and made of corrosion resistant materials. The valve assembly may be employed in either a passive or an active implantable drug or beneficial agent infusion system. | 0 |
CROSS-REFERENCE TO A RELATED APPLICATION
The invention described and claimed hereinbelow is also described in German Patent Application 10 2014 103 989.0, filed on Mar. 24, 2014. The European Patent Application, the subject matters of which is incorporated herein by reference, provides the basis for a claim of priority of invention under 35 U.S.C. 119(a)-(d).
BACKGROUND OF THE INVENTION
The present invention relates an adjustment device, for example, for adjusting seats.
EP 979 179 discloses a seat adjuster, in which a brake is provided between a fixed part and an adjustable part, to be able to block the two parts continuously in both adjustment directions. The brake can be released via a release element, to then be adjusted in one of the two directions using an adjustment body. An additional locking unit, which acts step-by-step, latches to lock the blocked position. Such latching is perceived to be annoying by the user, since, on the one hand, latching noises occur and on the other hand, latching cannot take place in intermediate positions. In addition, numerous parts are required for the pre-tensioning of the latch, which makes the installation complex.
WO 2012/013234 discloses an adjustment mechanism in which two clamping locks connected in series are provided, where each implements a freewheel brake. The two clamping locks comprise clamping elements, which enable continuous adjustment and blocking in both adjustment directions. The two clamping locks are coupled to one another in this case via a disengagement element, so that after the blocking of an output element by the first clamping lock, the second clamping lock can be switched into a freewheel position, to move an actuating lever back into a starting position. In this case, the actuating lever is pre-tensioned via a first lock spring in a starting position and the disengagement element is pre-tensioned via a second lock spring in a starting position. The two lock springs are arranged in series in the axial direction of the output shaft, so that a relatively large amount of construction space is required in the axial direction. In addition, the problem exists that one lock spring acts on the triggering element and the other lock spring acts on the lever adapter. The reset takes place relatively imprecisely due to tolerances and play.
SUMMARY OF THE INVENTION
The present invention overcomes the shortcomings of known arts, such as those mentioned above.
To that end, the present invention provides an adjustment device, which has a compact structure and enables a precise adjustment of a drive element in relation to an output element.
According to an embodiment of the invention, the adjustment device comprises a first clamping element freewheel and a second clamping element freewheel, by each of which one output element is blocked and released continuously in different positions in both adjustment directions. A release element is provided to release the first clamping element freewheel and an actuating element is provided to release the second clamping element freewheel. The drive element is pre-tensioned in a middle position in this case via two springs acting in different directions. The two springs also pre-tension the actuating element in a middle position. Thus, independently of the rotational direction of the drive element, one of the two springs is used for the reset into a starting position, i.e., a middle position. The respective other spring is used to reset the actuating element into a middle position, so that depending on the rotational direction of a spring, either the drive element or the actuating element is pre-tensioned in a middle position. A more compact structure thus results and the production of the adjustment device with only a few parts is enabled. The pre-tension of the actuating element is implemented essentially without play in this case, since the actuating element is directly moved and is pre-tensioned in a middle position during a movement of the drive element.
The first and the second clamping element freewheels can be implemented in each case as a clamping lock, in which clamping elements are provided between an outer ring and an inner ring, enabling continuous blocking in both adjustment directions. Like clamping locks are described in detail, for example, in WO 2012/013234 and are referred to hereafter as a clamping element freewheel, since a freewheel also can be achieved in addition to the blocking function.
Preferably, during a movement of the drive element in a first rotational direction, the drive element is pre-tensioned by a first of the two springs in the middle position and the actuating element is pre-tensioned by the other, second spring in the middle position. In contrast, if the drive element is moved in a second rotational direction, which is opposite to the first rotational direction, the drive element is pre-tensioned by the second spring in the middle position and the actuating element is pre-tensioned by the first spring in the middle position. Thus, depending on the rotational direction, the drive element and the actuating element can be pre-tensioned by the first spring or the second spring.
For a compact structure of the adjustment device and easy installation, the springs can be implemented as coiled springs. The springs are preferably held in a curve in a receptacle of a housing. In the middle position of the drive element and the actuating element, the springs are held with their end sides on a stop. In this case, a projection of the drive element is arranged between the end sides of the springs and a projection of the actuating element is arranged between two opposing end sides of the springs. Thus, with rotationally-fixed fixation of the actuating element on the drive element, an adjustment and blocking operation, which is essentially without play, is caused via the first and second clamping body freewheels.
In an embodiment of the invention, the output element has an axle and the drive element has a ring arranged around the axle. The ring forms a part of the second clamping body freewheel in this case, so that the drive part acts directly via the ring on the second clamping body freewheel, to reduce the number of parts. Of course, it also is possible to implement the drive element as the axle and the output element as the ring, to provide an adjustment device according to the invention.
The springs arranged in the curved receptacles on the housing are installed from a first side in the receptacles. Furthermore, at least one slot is provided on the curved receptacles, through which a projection is guided, which presses against an end side of the springs. The actuating element and the drive element are thus installed compactly inside the housing.
BRIEF DESCRIPTION OF THE DRAWINGS
Further features and advantages of the invention will become apparent from the description of embodiments that follows, with reference to the attached figures, wherein:
FIG. 1 presents a view of a seat having an adjustment device according to the invention;
FIG. 2 presents a perspective view of the adjustment device according to the invention;
FIG. 3 presents a perspective exploded illustration of the adjustment device of FIG. 2 ;
FIG. 4 presents a top view of a first clamping element freewheel of the adjustment device of FIG. 2 ;
FIG. 5 presents a view of the first clamping body freewheel of FIG. 4 with a release element;
FIG. 6 presents a top view of a second clamping body freewheel of the adjustment device;
FIG. 7 presents a view of the second clamping element freewheel with an actuating element;
FIG. 8 presents a perspective exploded illustration of a housing of the adjustment device;
FIG. 9 presents a view of the housing of the adjustment device with the springs, and
FIG. 10 presents a perspective view of the housing with the springs during the installation.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The following is a detailed description of example embodiments of the invention depicted in the accompanying drawings. The example embodiments are presented in such detail as to clearly communicate the invention and are designed to make such embodiments obvious to a person of ordinary skill in the art. However, the amount of detail offered is not intended to limit the anticipated variations of embodiments; on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the present invention, as defined by the appended claims.
A vehicle seat 1 is shown in FIG. 1 to comprise a seat body 2 , on which a backrest 3 is mounted to be pivotable. The seat body 2 is supported on a framework 4 , wherein the seat body 2 is held on the framework 4 via two parallel levers 5 . An adjustment device 6 , including a drive lever 7 that is rotatable about a horizontal axis in both directions, is installed on the seat body 2 . If the drive lever 7 is pivoted upward into a position 7 A, pivoting of the lever 5 clockwise can be initiated via the adjustment device 6 , whereby the seat surface 2 is lowered. If the drive lever 7 is pivoted downward into position 7 B, rotating of the lever 5 counterclockwise is caused via the gearing, so that the seat body 2 is raised.
In FIGS. 2 and 3 , the adjustment device 6 is shown. The adjustment device 6 comprises a housing 80 , which has a flange 8 with openings 9 on opposing sides, to fix the housing 80 on the seat body 2 . The housing 80 is closed on the upper side by a cover 50 , which is implemented as plate-shaped and has webs 52 , which engage between projections 55 of the housing. The housing 80 and the cover 50 are penetrated by an axle 17 .
As shown in FIG. 3 , the axle 17 has a smooth-walled section and a middle section having radially protruding wedges 19 , which are used for the rotationally-fixed fixation of an inner ring 12 of a first clamping body freewheel 10 . Furthermore, a protruding pinion 18 is provided on the axle 17 , which is engaged with a gearing, in particular a toothed rocker, which is implemented on a lever 5 or a part connected to the lever 5 , to be able to perform a vertical adjustment of the seat body 2 via the pinion 18 .
The first clamping element freewheel 10 comprises cylindrical clamping elements 13 and 13 ′, which press against a cylindrical internal surface of an outer ring 11 . Furthermore, the clamping bodies 13 and 13 ′ press against the inner ring 12 , which has a round contour, and has a flattening 14 in each case in the region of the clamping elements 13 and 13 ′. A block 45 made of an elastic material is inserted between the clamping elements 13 and 13 ′. The inner ring 12 can be blocked and released in both directions in relation to the outer ring 11 via the clamping elements 13 and 13 ′.
In a starting position, inner ring 12 and outer ring 11 are blocked in relation to one another, since in each case one of the clamping elements 13 and 13 ′ causes a blocking in one direction. If the clamping element 13 is moved slightly by a release element 70 having projections 71 in a circumferential direction, the release is achieved and the blocking is canceled. The inner ring 12 can then be rotated in relation to the outer ring 11 in a first rotational direction. If the release element 70 having the projections 71 is moved in the opposite direction and the clamping element 13 ′ is shifted, a movement of the inner ring 12 in relation to the outer ring 11 in the opposite direction is released.
The outer ring 11 is connected rotationally-fixed in this case to a housing lower part, which is implemented as plate-shaped and has outwardly protruding webs 15 . Upwardly protruding sleeves 16 are provided on the webs 15 , which engage in the openings 9 of the housing 80 , so that housing lower part and housing 80 are fixed in a rotationally-fixed manner on one another.
The adjustment device 6 according to the invention furthermore comprises a second damping element freewheel 20 , which is released via an actuating element 40 . The second clamping element freewheel 20 comprises in this case an outer ring 30 , which has two radially protruding projections 31 having openings 32 , on which the drive lever 7 is fixed.
The first clamping element freewheel 10 and the second clamping element freewheel 20 are arranged inside the housing 80 , which is closed using the cover 50 . The cover 50 has an internal opening 51 for leading through one end of the axle 17 . Furthermore, recesses 53 are provided between the webs 52 , in which the projections 55 , which protrude from a support surface 54 , engage.
FIG. 4 shows the first clamping element freewheel 10 in a top view. The inner ring 12 comprises a nonround contour having flattenings 14 , at each of which a pair made of a clamping element 13 and a clamping element 13 ′ is provided. An elastic block 45 is arranged between the clamping elements 13 and 13 ′ of a pair. Between two clamping elements 13 and 13 ′, at which no elastic body 45 is provided, i.e., between two adjacent pairs of clamping elements 13 , 13 ′, a projection 71 of a release element 70 engages in each case, wherein the release element 70 is implemented as essentially ring-shaped and is connected on the inner side in a rotationally-fixed manner to the axle 17 . The projections 71 are bent over and engage essentially in a formfitting manner or with little play between the clamping elements 13 and 13 ′, as shown in FIG. 5 .
The second clamping element freewheel 20 is shown in FIG. 6 . The clamping element freewheel 20 comprises an inner ring 21 , which has receptacles for the wedges 19 of the axle 17 on the inner side and is therefore connected in a rotationally-fixed manner to the axle 17 . The inner ring 21 is implemented as cylindrical on the outer circumference and presses against clamping elements 22 and 22 ′. An outer ring 30 is provided around the clamping elements 22 and 22 ′, which implements a cross section deviating from the cylindrical body, to jam the clamping elements 22 and 22 ′ in opposite directions. An elastic block 23 is provided between the clamping elements 22 and 22 ′. In a starting position, the inner ring 21 is blocked in relation to the ring 30 in opposite directions, wherein a release of the blocking occurs when in each case one of the clamping elements 22 or 22 ′ is shifted against the force of the elastic block 23 , so that then the ring 30 can be rotated in relation to the inner ring 21 in one direction. The function of the second clamping element freewheel 20 is therefore similar to the first clamping element freewheel 10 . In the second clamping element freewheel 20 , the outer ring 30 is coupled to the drive lever 7 via the projections 31 .
In FIG. 7 , an essentially disk-shaped actuating element 40 is placed on the second clamping element freewheel 20 . The actuating element 40 is ring-shaped and comprises projections 41 protruding perpendicularly downward, which engage between two clamping elements 22 and 22 ′, to displace one of the clamping elements 22 or 22 ′ depending on the rotational direction and thus achieve a release. Furthermore, the actuating element 40 is provided with an internal cylindrical opening 43 , through which the axle 17 is guided. A protruding web 42 is implemented on one side of the actuating element 40 , which engages between two springs 60 and 61 , as will be explained hereafter.
FIG. 8 shows the housing 80 with the two springs 60 and 61 . The springs 60 and 61 are implemented as coiled springs and are arranged essentially in a semicircle inside the housing 80 . The springs 60 and 61 , which are compression springs, and are each held in a curve in a receptacle, wherein one end side of the springs 60 and 61 is supported in each case on a first stop 62 or an opposing stop 65 . A slot 63 is provided on the stop 62 and a slot 64 is provided on the stop 65 . The actuating element 40 engages with the projection 42 in the slot 64 . On the opposite side, a projection 33 on the ring 30 engages in the slot 63 . During the rotation of the ring 30 , firstly the second clamping element freewheel 20 is unlocked and then moves, via the clamping element 22 or 22 ′, the actuating element 40 , which is moved via the projections 41 with the clamping elements 22 and 22 ′. The projection 42 thus also moves in the rotational direction of the ring 30 against the force of one of the springs 60 or 61 .
FIG. 9 shows the housing 80 with the springs 60 and 61 , which are held in curved receptacles. The stops 62 and 65 also can be seen, on each of which a slot 63 or 64 is implemented. The springs 60 and 61 are arranged essentially in a plane perpendicular to the longitudinal direction of the axle 17 , the springs 60 and 61 at least overlap in this plane, so that a more compact structure is obtained.
FIG. 10 shows the housing 80 in an exploded illustration. The housing 80 comprises curved receptacles 66 and 67 , in each of which a spring 60 or 61 , respectively, is received. As FIG. 10 shows, the slot 64 is not only located in the region of the stop 65 , but rather also extends as the slot 68 into the receptacle 66 and the receptacle 67 . The actuating element 40 can thus be moved from a middle position, in which the projection 42 is arranged in the region of the stop 65 , in both rotational directions along the slot 68 . On the opposite side, the slot 63 is provided on the stop 62 , which extends on opposite sides as the slot 69 . The projection 33 of the ring 30 is thereby rotated out of the middle position against the force of the springs 60 or 61 in opposite directions.
In the event of a movement of the drive lever 7 downward from a middle position, an adjustment operation is initiated, in that the output element is rotated using the pinion 18 . If the drive lever 7 is then let loose, one of the springs 60 or 61 causes a reset into the blocked position, so that a manual adjustment operation of the seat body 2 may be carried out. Vice versa, the drive lever 7 is then moved upward out of the middle position, to cause an adjustment of the seat body upward, wherein then the pinion 18 is blocked in the adjusted position and the drive lever 7 is pivoted back into its middle position by the force of one of the springs 60 or 61 .
LIST OF REFERENCE NUMERALS
1 seat
2 seat body
3 backrest
4 framework
5 lever
6 adjustment device
7 drive lever
7 A position
7 B position
8 flange
9 opening
10 clamping element freewheel
11 outer ring
12 inner rings
13 , 13 ′ clamping elements
14 flattening
15 web
16 sleeve
17 axle
18 pinion
19 wedge
20 clamping element freewheel
21 inner ring
22 , 22 ′ clamping elements
23 block
30 outer ring
31 projection
32 opening
33 projection
40 actuating element
41 projection
42 web/projection
43 opening
45 block
50 cover
51 opening
52 web
53 recess
54 support surface
55 projection
60 spring
61 spring
62 stop
63 slot
64 slot
65 stop
66 receptacle
67 receptacle
68 slot
69 slot
70 release element
71 projection
80 housing
As will be evident to persons skilled in the art, the foregoing detailed description and figures are presented as examples of the invention, and that variations are contemplated that do not depart from the fair scope of the teachings and descriptions set forth in this disclosure. The foregoing is not intended to limit what has been invented, except to the extent that the following claims so limit that. | An adjustment device for adjusting seats includes a rotatable drive element, a rotatable output element, a first clamping element freewheel that blocks the output element continuously in different positions in both adjustment directions and that is released by a release element and a second clamping element freewheel that is coupled via the release element to the first clamping element freewheel, blocks the output element continuously in different positions in both adjustment directions and is released by an actuating element. The drive element is pre-tensioned in a middle position via two springs acting in different directions and the two springs pre-tension the actuating element in a middle position. | 1 |
This application is a continuation in part of application Ser. No. 07,362,932, filed June 8, 1989, now abandoned.
BACKGROUND OF THE INVENTION
A) Field of the Invention
This invention relates to novel 5-[1-(imidazol)methyl]-3,3-diphenyl-2(3H)furanone and 3-cycloalkyl-5-[1-(imidazol)methyl]-3-phenyl-2(3H)furanone derivatives, their pharmaceutically acceptable quaternary alkyl and acid addition salts and their use in disorders in which anticholinergic agents are effective.
B) State of the Art
Antagonism of the action of acetylcholine at muscarinic cholinergic receptors in various tissues produces antispasmodic, antisecretory and mydriatic effects. As a result, such compounds have a broad range of therapeutic applications, notably as antispasmodics, as an adjunct in the treatment of peptic ulcer, as adjuvants in the treatment of functional disorders of the bowel or bladder, such as irritable bowel syndrome, spastic colitis, ulcerative colitis, diverticulitis and neurogenic bladder disorders (B. V. Rama Sastry in "Burger's Medicinal Chemistry", M. E. Wolff, Ed., 4th Ed., Part III, chap. 44, pg. 361).
Furanones have long been known in the realm of natural products chemistry. Pilocarpine, a 4-[1-(imidazol)methyl]-2(3H)furanone is a naturally occurring muscarinic agonist (L. S. Goodman, A. Gilman, "The Pharmacological Basis of Therapeutics", 6th Ed., 1980, p. 87). 5-[(Diethylamino)-methyl]-4,5-dihydro-3,3-diphenyl-2(3H)furanone is a furanone for which antiarrhythmic effectiveness in mammalian heart tissue, but not anticholinergic properties, has been described (A. Pohland, S. African Patent 68 05,631, Mar. 2, 1970, Eli Lilly and Co., U.S. applied Nov. 13, 1967). Another furanone, a spasmolytic that prevents contractions of isolated guinea pig ileum, is 3-[(dimethylamino)methyl]-4,5-dihydro-5,5-diphenyl-2(3H)furanone (N. Kolokouris, G. Eytas, C. Brunet, M. Luyckx, Ann. Pharm. Fr., 43(3), 1985, p.257).
The majority of presently known antimuscarinic agents are structurally similar to solanaceous alkaloids, e.g., atropine, or a diverse group of compounds including hydroxyesters, e.g., oxybutynin, amides, e.g., tropicamide, and amino alcohols, e.g., procyclidine. These groups of compounds block the effect of acetylcholine on the cholinergic receptor. The isopropyl quaternary bromide of atropine, i.e. ipratropium bromide, is particularly noteworthy for its use as a bronchodilator in the treatment of respiratory disorders, such as asthma and chronic bronchitis (G. E. Pakes, R. N. Brogden, R. C. Heel, T. M. Speight, G. S. Avery, Drugs, 20, 1980, 237-266).
The present invention provides a novel class of 5-[1-(imidazol)methyl]-3,3-diphenyl-2(3H)furanone and 3-cycloalkyl-5-[1-(imidazol)methyl]-3-phenyl-2 (3H)furanone derivatives which have anticholinergic activity.
SUMMARY OF THE INVENTION
The invention provides novel compounds of the formula: ##STR2## wherein: the dashed line indicates either the 4,5-unsaturated or the 4,5-dihydrofuranone ring;
R 1 and R 2 may be the same or different and are hydrogen, thienyl, furanyl, or cycloalkyl (C 3 -C 6 ), benzyl, phenyl, substituted phenyl or substituted benzyl wherein the phenyl or benzyl group may be substituted with halogen, trifluoromethyl, lower alkyl, lower alkoxy or hydroxy;
R 3 is hydrogen, lower alkyl, lower alkyl substituted with a halogen, alkoxy, amino, carboxylic acid, ester or amide group, benzyl, phenyl, nitro, trifluoromethyl, a cycloalkyl group containing 3 to 6 carbons, halogen, or part of an alkylene bridge to form a quaternary salt with the double bonded imidazole nitrogen, substituted phenyl or substituted benzyl, for which the substituents are the same as those set forth for R 1 and R 2 substituted benzyl or phenyl;
R 4 and R 5 may be the same or different and are the groups described for R 3 or are joined together to form an alkylene bridge;
R 6 is hydrogen or lower alkyl (in the 4,5-dihydrofuranone series); and the pharmaceutically acceptable salts of such compounds, particularly the quaternary alkyl (C 1 -C 4 ) and acid addition salts of such compounds. (The foregoing formula is referred to herein as Formula I).
As used herein, lower alkyl or lower alkoxy refer to groups having one to six carbons and cycloalkyl (C 3 -C 6 ) refers to cycloalkyls having three to six carbons in the cyclic group, including cyclopropyl, cyclobutyl, cyclopentyl or cyclohexyl. The alkylene bridges contemplated with respect to R 3 , R 4 and R 5 may have one, two, three, four or more carbons. Each R group may be different than the other groups, i.e. each R group is independently selected. The invention includes lower alkyl quaternary salts of the foregoing compounds. The invention also includes pharmaceutical compositions effective as anticholinergics and therapeutic methods utilizing such compounds in those disorders in which anticholinergic agents are recognized to be effective, including treatment of neurogenic bladder disorders.
DETAILED DESCRIPTION OF THE INVENTION
The invention is directed to 5-[1-(imidazol)methyl]-3,3-diphenyl-2(3H)furanone and 3-cycloalkyl-5-[1-(imidazol)methyl]-3-phenyl-2(3H)furanone derivatives of Formula I set forth above. Compounds of the invention include those in which R 1 and R 2 are independently selected from phenyl, thienyl, furanyl and substituted phenyl and R 3 , R 4 and R 5 are each independently a lower alkyl. Preferred compounds include those in which R 1 and R 2 are phenyl and R 3 , R 4 and R 5 are each independently a lower alkyl. The preferred compounds of the invention are those in which R 1 and R 2 are phenyl or substituted phenyl. The most preferred R 3 groups are hydrogen and lower alkyl groups. Preferably R 4 and R 5 groups are both hydrogen or methyl. Among the preferred compounds are 5-[1-(2-ethylimidazol)methyl]-4,5-dihydro-3,3-diphenyl-2(3H)furanone, 5-[1-(2-propylimidazol)-methyl]-4,5-dihydro-3,3-diphenyl-2 (3H)furanone, 5-[1-(2-methylimidazol)methyl]-4,5-dihydro-3,3-diphenyl-2(3H)furanone and 5-[1-(2-isopropylimidazol)methyl]-4,5-dihydro-3,3-diphenyl-2(3H)furanone. Other preferred compounds include (R)-(+)-5-[1-(2-ethylimidazol)methyl]-4,5-dihydro-3,3-diphenyl-2(3H)furanone, 5-[1-(2-n-propylimidazol)methyl]-4,5-dihydro-3,3-diphenyl-2(3H)furanone, 5-[1-(2-ethylimidazol)methyl]-3,3-diphenyl-2(3H)furanone, 5-[1-(2-ethyl-3-methylimidazol)methyl]-4,5-dihydro-3,3-diphenyl-2(3H)furanone bromide, 5-[1-(2-tert-butylimidazol)methyl]-4,5-dihydro-3,3-diphenyl-2(3H)furanone, 6,7-dihydro-1-[(2,3,4,5-tetrahydro-5-oxo-4,4-diphenyl-2-furanyl)methyl]-5H-pyrrolo[1,2-a]imidazolium chloride, 5-[1-(2-isopropylimidazol)methyl]-3,3-diphenyl-2(3H)furanone, (R)-(+)-5-[1-(2-isopropylimidazol)methyl]-4,5-dihydro-3,3-diphenyl-2(3H)furanone.
The compounds of the invention act as cholinergic receptor antagonists and have a variety of antimuscarinic therapeutic applications, particularly in the treatment of neurogenic bladder and pulmonary disorders. As a result of their action on bladder contraction, and their antispasmodic and antisecretory effects, they are of particular benefit in the treatment of urinary incontinence. The compounds also can be expected to produce antispasmodic, antisecretory and mydriatic effects useful in other disorders, notably as antispasmodics, as an adjunct in the treatment of peptic ulcer, and as adjuvants in the treatment of functional disorders of the bowel or bladder, such as irritable bowel syndrome, spastic colitis, ulcerative colitis and diverticulitis. The quaternary salts of this invention are particularly useful as bronchodilators, notably in the treatment of asthma and chronic bronchitis.
To the extent the compounds of the invention may exist as optical or geometric isomers, all isomers and racemic mixtures are to be understood to be included in the invention. In addition, all possible other isomeric forms of the compounds of the invention are within the ambit of this invention.
The compounds of this invention may be used in the form of a nontoxic, pharmaceutically acceptable acid addition salt having the utility of the free base. Such salts, prepared by methods well known to the art, are formed with both inorganic or organic acids, for example: maleic, fumaric, benzoic, ascorbic, pamoic, succinic, bismethylenesalicyclic, methanesulfonic, ethanedisulfonic, acetic, oxalic, propionic, tartaric, salicylic, citric, gluconic, lactic, malic, mandelic, cinnamic, citraconic, aspartic, stearic, palmitic, itaconic, glycolic, p-aminobenzoic, glutamic, benzenesulfonic, hydrochloric, hydrobromic, sulfuric, cyclohexylsulfamic, phosphoric and nitric acids.
The compounds of this invention may be administered orally, parenterally, or by inhalation in conventional dosage unit forms such as tablets, capsules, injectables, aerosols, or the like, by incorporating the appropriate dose of a compound of Formula I with carriers according to accepted pharmaceutical practices.
Preferably a compound or an acid addition salt thereof is administered orally to an animal organism in a tablet, capsule or aerosol containing an amount sufficient to produce the desired activity of a cholinergic antagonist. Each dosage unit will contain the active ingredient in an amount of about 0.1 mg to about 40 mg. Advantageously equal doses will be administered three to four times daily with the daily dosage regimen being about 1 mg to about 160 mg, preferably from about 6 mg to about 80 mg.
The pharmaceutical carrier employed may be, for example, either a solid or liquid. Exemplary of solid carriers are lactose, terra alba, sucrose, talc, gelatin, agar, pectin, acacia, magnesium stearate, stearic acid and the like. Exemplary of liquid carriers are syrup, peanut oil, olive oil, water and the like. Similarly the carrier or diluent can include any time delay material well known to the art, such as glycerol monostearate or glycerol distearate alone or with a wax.
A wide variety of pharmaceutical forms can be employed. Thus, if a solid carrier is used, the preparation can be tableted, placed in a hard gelatin capsule in powder or pellet form, or in the form of a troche or lozenge. The amount of solid carrier will vary widely but preferably will be about 25 mg to about 1 g. If a liquid carrier is used, the preparation will be in the form of a syrup, emulsion, soft gelatin capsule, aerosol, sterile injectable liquid such as an ampoule, or an aqueous or non-aqueous liquid suspension.
The compounds of the invention can be prepared by alkylation of substituted acetic acids. For example, diphenylacetic acid was dilithiated and treated with allyl bromide to yield 2,2-diphenyl-4-pentenoic acid. This acid was cyclized to the furanone by treatment of its sodium salt with bromine. The resulting 5-(bromomethyl)-4,5-dihydro-3,3-diphenyl-2(3H)furanone is allowed to react with the substituted imidazole, under thermal conditions, to eventually give the compounds of the invention. Alternatively, a 2,2-disubstituted-4-pentenoic acid was oxidized to an epoxide which was treated with base to give a 5-hydroxymethyl-4,5-dihydro-3,3-disubstituted-2-(3H)furanone which was sequentially converted to the corresponding 5-bromomethyl or triflate derivative. This, in turn, was employed for alkylation of the appropriate imidazole, prepared from an alkyl cyanide via an imidate and condensation with aminoacetaldehyde dimethyl acetal, to produce a 5-[1-(imidazol)methyl]-4,5-dihydro-3,3-disubstituted-2(3H)furanone. Stereoselective syntheses of compounds of this invention proceeded from (R) and (S)-2,2-dimethyl-4-(hydroxymethyl)-1,3-dioxolane via the corresponding 4-iodomethyl derivative with which a phenylacetic acid was alkylated. Hydrolysis of the dioxolane afforded a diol, which following lactonization to the corresponding 5-hydroxymethyl-4,5-dihydro-3,3-disubstituted-2(3H)furanone, was used to alkylate an imidazole as indicated in preceding route. Base-induced dehydrohalogenation of 5-bromomethyl-4,5-dihydro-3,3-disubstituted-2(3H)furanones afforded 4,5-dehydro-5-methyl derivatives which, following bromination, were utilized to alkylate an appropriate imidazole to give the unsaturated (4,5-dehydro) 2-(3H)furanones of this invention. Quaternary alkyl derivatives were obtained by treatment of 5-[1-(imidazol)methyl]-3,3-disubstituted-2(3H) furanones with an alkyl halide or by appropriate alkylation of a quaternary alkylimidazole.
The following examples are illustrative of the invention. Temperature is expressed in degrees Celsius; NMR signals are given as ppm downfield from an internal standard of Me 4 Si.
EXAMPLES
EXAMPLE I
1-DIMETHYLAMINOMETHYLIMIDAZOLE
Imidazole (20.4 g, 0.3 mole) and 26 g (0.3 mole) of dimethylamine hydrochloride were stirred with 50 mL of water and the cooled solution adjusted to pH 4.97 with concentrated hydrochloric acid. A 37% solution of formaldehyde (27 g, 0.33 mole) was added and the mixture allowed to stand three days. The pH was adjusted to 14 with 20% aqueous potassium hydroxide before the product was salted out by adding solid K 2 CO 3 . The organics were extracted with methylene chloride, dried (K 2 CO 3 ) and evaporated at reduced pressure. The residue was distilled in a Kugelrohr apparatus at 0.1 mm and 95° C. and gave 30.8 g (83%) of pure product.
2-BUTYLIMIDAZOLE
1-Dimethylaminomethylimidazole (5.0 g, 40 mmol.) was stirred in 80 mL of tetrahydrofuran under argon at -78° C. and 20 mL (48 mmol.) of 2.4 M n-butyllithium in hexane was added dropwise. After 1 hour, 8.8 g (48 mmol.) of 1-iodobutane was added and the mixture was stirred 1 hour at -78° C. before removing the cooling bath and stirring overnight. The reaction was made acidic by adding 60 mL of 2N hydrochloric acid and the organic solvents were evaporated at reduced pressure. Solid NaHCO 3 was added to the aqueous residue before extracting the mixture with methylene chloride. The extracts were dried (MgSO 4 ) and evaporated at reduced pressure to give an oil. Kugelrohr distillation at 0.1 mm and 125°-120° C., gave 2.1 g (43%) of product.
The following imidazoles were prepared by an analogous method.
2-Isobutylimidazole (mp 125°-126° C.),
2-Benzylimidazole (mp 123°-124.5° C.).
EXAMPLE II
2-TERT-BUTYLIMIDAZOLE
tert-Butylnitrile (25 g, 0.3 mole) and 17.4 mL (0.3 mole) of absolute ethanol were stirred at 25° C. under argon and gaseous hydrogen chloride was slowly bubbled in the solution. After 5 days at 25° C., 200 mL of ether was added to afford 18.6 g (37%) of a solid which was characterized as ethyl tert-butylimidate. This product (18.6 g, 0.112 mole) was stirred in 20 mL of methanol and, after adding 13.0 g (0.123 mole) of aminoacetaldehyde dimethylacetal, the mixture was allowed to stand at 25° C. for 3 days. Concentration of the solution in vacuo at 88° C. gave 26.6 g of a residual liquid to which were added 30 mL of concentrated hydrochloric acid and 20 mL of water. The mixture was concentrated in vacuo at 88° C. to give 20 g of a dark viscous liquid. A suspension of this residue in 10 mL of water was adjusted to pH 10 with solid K 2 CO 3 . Following removal of the water in vacuo, the residue was stirred with 200 mL of ethanol. The resulting mixture was filtered and the filtrate was concentrated under reduced pressure to afford a solid residue. Sublimation of this solid afforded 9.0 g of a crystalline product, mp 224°-225° C.
The following imidazoles were prepared in an analogous manner:
2-Isobutylimidazole (mp 125°-126.5° C.),
2-Benzylimidazole (mp 123°-124° C.),
2-(2-Methoxyethyl)imidazole (Kugelrohr bp 90°-95° C. at 0.1 mm),
2-(2-Hydroxyethyl)imidazole (mp 128°-129° C.),
2-(4-Chlorobutyl)imidazole (an oil from chromotography and identified by 1 H NMR),
2-(3-Chloropropyl)imidazole (hygroscopic solid employed for further reaction without purification).
EXAMPLE III
5,6,7,8-TETRAHYDROIMIDAZO[1,2-A]PYRIDINE
To a solution of 11.0 g (69.3 mmol.) of 2-(4-chlorobutyl)imidazole in 90 mL of methyl ethyl ketone and 10 mL of dioxane was added 12.0 g (80.0 mmol.) of sodium iodide and 5.0 g (36.2 mmol.) of potassium carbonate. After the mixture was stirred and refluxed for 20 hours, it was cooled to 25° C. and filtered. The filtrate was concentrated in vacuo. The residue was dissolved in 40 mL of methanol, 10 mL of propylene oxide was added, and the solution was stirred at 25° C. for 20 hours. Concentration of the solution in vacuo afforded a liquid which was applied to 300 g of silica and eluted with 2% methanol in methylene chloride to give 2.2 g of a colorless liquid which was identified by 1 H NMR.
6,7-Dihydro-5H-pyrrolo[1,2-a]imidazole was prepared from 2-(3-chloropropyl)imidazole in a similar manner; it was sublimed at 80° C. and 0.1 Torr. to give a hygroscopic white solid.
EXAMPLE IV
8-METHYLIMIDAZO[1,2-A]PYRIDINE
To a mixture of chloroacetaldehyde [25.4 mL (0.2 mole) of a 50% aqueous solution]and 18.8 g (0.2 mole) of 2-amino-3-methylpyridine in 150 mL of water was added 16.8 g (0.2 mole) of sodium bicarbonate. After being stirred at 25° C. for 3 days, the mixture was acidified with concentrated hydrochloric acid and stirred an additional 30 minutes. After the pH was adjusted to 10 by addition of sodium hydroxide, the mixture was saturated with sodium chloride and extracted with ether. The ether extracts were dried and concentrated to give 16.3 g (62%) of a liquid residue, bp 68°-70° C. at 0.1 Torr.
Imidazo[1,2-a]pyridine, bp 61°-66° C. at 0.1 Torr., was prepared in an analogous manner.
EXAMPLE V
5,6,7,8-TETRAHYDRO-8-METHYLIMIDAZO[1,2-A]PYRIDINE
A mixture of 2.0 g (15.1 mmol.) of 8-methylimidazo[1,2-a]pyridine and 2 teaspoonsful of Raney nickel 2800 in 40 mL of n-butanol was hydrogenated at an initial pressure of 55 psi of hydrogen at 65° C. for 24 hours. The mixture was filtered and the filtrate was concentrated in vacuo. The residual liquid was chromatographed (silica, 40 g, 98: 2, methylene chloride: methanol to give 1.1 g of product as an oil. 1 H NMR(CDCl 3 )δ 1.32(d, J=7.4 Hz, 3H), 1.42-1.58(m 1H), 1.82-2.0(m, 1H), 2.0-2.12(m, 2H), 2.82-2.99(m, 1H) 3.80-4.02(m, 2H), 6.74(d, J=1.5 Hz, 1H), 6.97(d, J=1.5 Hz, 1H); analytical TLC (silica, 95: 5, methylene chloride: methanol) Rƒ 0.46.
EXAMPLE VI
2-ETHYL-1-METHYLIMIDAZOLE
A mixture of 50 g (0.52 mole) of 2-ethylimidazole, 104 g (0.78 mole) of potassium carbonate, 1.4 g (5.2 mmol.) of [18]-crown 6 and 260 mL of dimethyl carbonate was stirred and refluxed for 3 days. The mixture was then filtered and the filter cake was washed with ether. The filtrate and washings were concentrated in vacuo and the resulting residue was partitioned between water and ether. After the ether layer was separated, it was dried over MgSO 4 , concentrated and distilled to give 17 g (30%) of a colorless liquid, bp 65-75° C. at 0.1 Torr.
2-Isopropyl-1-methylimidazole, a colorless liquid, bp 70° C. at 0.1 Torr, was prepared in an analogous manner.
EXAMPLE VII
1-TRITYLIMIDAZOLE
To a stirred solution of 23.5 g (0.35 mole) of imidazole in 425 mL of ethyl acetate was added 48.0 g (0.32 mole) of triphenylmethyl chloride. The mixture was stirred for 20 hours and then 500 mL of water was added. After being stirred for an additional 2 hours, the mixture was filtered. The ethyl acetate layer was separated, dried (MgSO 4 ) and concentrated. Recrystallization of the residue from xylene gave 41 g of white crystals, mp 222°-225° C..
2-CARBOMETHOXY-1-TRITYLIMIDAZOLE
To a stirred solution of 12.4 g (40 mmol.) of 1-tritylimidazole in 250 mL of tetrahydrofuran, under argon, at 0° C. was added 20 mL (48 mmol.) of a solution of n-butyl-lithium in hexane. After the solution was allowed to warm to ambient temperature, it was stirred for 1 hour and then 3.4 mL (50 mmol.) of methyl chloroformate was added dropwise. The mixture was stirred for 20 hours at 25° C., 100 mL of water was added and then the mixture was concentrated in vacuo. The residue was extracted with ether. After the extracts were dried (MgSO 4 ) and concentrated, the residue was chromatographed on 200 g of silica using 1:3 ethyl acetate: hexane, followed by 1:1 ethyl acetate: hexane, and finally ethyl acetate to give 3.2 g of colorless product.
2-CARBOMETHOXYIMIDAZOLE
After a solution of 3.2 g (8.7 mmol.) of 1-trityl-2-carbomethoxyimidazole in 40 mL of a 5% solution of acetic acid in methanol was refluxed for 30 minutes, it was concentrated in vacuo. Recrystallization from ethanol afforded colorless needles, mp 187°-188° C.
EXAMPLE VIII
2,2-DIPHENYL-4-PENTENOIC ACID
A solution of diphenylacetic acid (250 g., 1.17 mol ) in 2.4 L of tetrahydrofuran was stirred at 0° C. under argon while 0.94 L of a 2.5M solution on n-butyllithium in hexane was added dropwise. After 1 hour, allyl bromide (142.5 g, 1.17 mole) was added in one portion. After 15 minutes, 500 mL of 10% hydrochloric acid was added, along with ether (2 L). The layers were separated, the aqueous layer extracted with ethyl ether (1×250 mL), the organic layers combined, washed with brine, dried (MgSO 4 ), and filtered. Concentration afforded 296 g (99%) of an off-white solid, mp 134°-137° C. 1H NMR (CDCl 3 )δ 7.3 (m, 10H), 5.6 (m, 1H), 4.9 (bs, 2H), 3.2 (d, 2H).
5-BROMOMETHYL-4,5-DIHYDRO-3,3-DIPHENYL-2(3H)FURANONE
To a stirred mixture of tetrahydrofuran:water (9:1, 1.65 L) was added 2,2-diphenyl-4-pentenoic acid (296 g, 1.17 mole) and sodium bicarbonate (98.85 g, 1.17 mole). After the mixture had become homogeneous, bromine (188 g, 1.17 mole) was added dropwise. After 1 hour, a solution of sodium thiosulfate (10 g) in 250 mL of water was added, then the mixture was stirred for 10 minutes. Ether (1 L) was added and the layers separated. The organic layer was washed with brine, dried (MgSO 4 ), and filtered. Concentration afforded 364 g of an oil which crystallized upon standing. Recrystallization from ether gave 230 g (59%) of a white crystalline solid, mp 84°-85° C. IR (KBr) 1766 cm -1 . 1 H NMR (CDCl 3 ) 7.45-7.27 (m, 10H), 4.5 (m, 1H), 3.5 (m, 2H), 3.2 (dd, 1H, J=13.1), 2.8 (dd, 1H, J=10, 13 1).
5-[1-(IMIDAZOL)METHYL]-4,5-DIHYDRO-3,3-DIPHENYL-2(3H)FURANONE
5-(Bromomethyl)-4,5-dihydro-3,3-diphenyl-2(3H)furanone (1.5 g, 4.5 mmol.) and imidazole (2 g) were dissolved in dimethylformamide (6 mL). This solution was heated under argon to 100° C. for 20 hours. After being cooled, the mixture was partitioned between saturated sodium bicarbonate solution (25 mL) and methylene chloride (200 mL) and the layers separated. The organic layer was washed with water (2×50 mL), then washed with brine and dried (MgSO 4 ). Filtration, followed by concentration, afforded a solid. Recrystallization from ether gave (0.7 g, 50%) of a white solid, mp 146°-148° C. IR (KBr) 1777 cm -1 . 1 H NMR (CDCl 3 ) 7.5-7.1 (m, 13H), 4.55 (m, 1H), 4.3 (dd, 1H), 4.16 (dd, 1H), 2.99 (dd, 1H), 2.5 (dd, 1H). Anal. calcd. for C 20 H 18 N 2 O 2 : C, 75.45; H, 5.69; N, 8.79. Found: C, 75.31; H, 5.76; N, 8.71.
EXAMPLE IX
5-[1-(3-METHYLIMIDAZOL)METHYL]-4,5-DIHYDRO-3,3-DIPHENYL-2(3h)FURANONE BROMIDE HYDRATE
5-(Bromomethyl)-4,5-dihydro-3,3-diphenyl-2(3H)furanone (1.35 g, 4.07 mmol.), 1-methylimidazole (0.35 g, 4.07 mmol.) and ether (5 mL) were placed into a sealed tube. The tube was filled with argon, capped and heated at 110° C. for 18 hours. After the solution was cooled, the gummy residue was removed and triturated with acetone to give a crystalline solid. Recrystallization from acetone afforded a white, hydroscopic solid, mp 148°-152° C. (0.70 g, 42%). IR (KBr) 1758 cm -1 . 1 H NMR (DMSO-d 6 ) 9.1 (S, 1H), 7.7 (dd, 2H), 7.4-7.4 (m, 10H), 4.6 (m, 1H), 3.86 (S, 3H), 3.3 (dd, 1H), 2.8 (dd, 1H). Anal. calcd. for C 21 H 21 N 2 O 2 Br.H 2 O: C, 58.47; H, 5.37; N, 6.49; Br, 18.52. Found: C, 57.91; H, 5.40; N, 6.40; Br, 18.41.
The following compounds (melting point in parentheses) were also prepared by the sequence of reactions set forth in Examples VIII and IX.
5-[(1-Imidazol)methyl]-4,5-dihydro-3,3-diphenyl-2(3H)furanone (146°-148° C.),
5-[1-(2-Methylimidazol)methyl]-4,5-dihydro-3,3-diphenyl-2(3H)furanone (106°-108° C.),
5-[1-(2-Ethylimidazol)methyl]-4,5-dihydro-3,3-diphenyl-2(3H) furanone hydrochloride (265°-268° C.),
5-[1-(3-Methylimidazol)methyl]-4,50-dihydro-3,3-diphenyl-2(3H)furanone bromide hydrate (148°-152° C.),
5-[1-(2,3-Dimethylimidazol)methyl]-4,5-dihydro-3,3-diphenyl-2(3H)furanone bromide (240°-243° C.),
5-[1-(2-Methyl-3-benzylimidazol)methyl]-4,5-dihydro-3,3-diphenyl-2(3H)furanone bromide (218°-220° C.),
5-[1-(2-Isopropylimidazol)methyl]-4,5-dihydro-3,3-diphenyl-2(3H)furanone (108°-109° C.),
5-[1-(2-Butylimidazol)methyl]-4,5-dihydro-3,3-diphenyl-2(3H)furanone (134°-135° C.),
5-[1-(Propylimidazol)methyl]-4,5-dihydro-3,3-diphenyl-2(3H)furanone (168°-169° C.),
5-[1-(3-Ethylimidazol)methyl]-4,5-dihydro-3,3-diphenyl-2(3H)furanone (155°-160° C.).
EXAMPLE X
5-(HYDROXYMETHYL)-4,5-DIHYDRO-3,3-DIPHENYL-2(3H)-FURANONE
2,2-Diphenyl-4-pentenoic acid (5.0 g, 20 mmol.), 20 mL of formic acid and 2.4 mL (22 mmol.) of 30% hydrogen peroxide were stirred at 70° C. for 25 hours at ambient temperature. The solvents were evaporated at reduced pressure, the residue taken up in 20 mL of methanol and a solution of 750 mg solid NaOH in 10 mL of water was added. The mixture was warmed at 70° C. to solution, about 1 hour before cooling and acidifying with 6N hydrochloric acid. The product was extracted with ether, the organics dried (MgSO 4 ) and evaporated at reduced pressure to give an oil in quantitative yield, the H NMR indicated a clean reaction product which was carried on without further purification. Analytical TLC (silica, 9:1, methylene chloride: EtAc) Rƒ 0.35; IR (neat) 3419, 3060, 2936, 1763, 1177, 786, 763, 699 cm -1 ; 1 H NMR (CDCl 3 )δ 2.5-2.65 (bs, 1H), 2.84-3.02 (m, 2H), 3.64-3.72 (m, 1H), 3.92-4.00 (m, 1H), 4.41-4.51 (m, 1H), 7.2-7.4 (m, 10H).
5-(TRIFLUOROMETHANESULFONYLOXYMETHYL)-4,5-DIHYDRO-3,3-DIPHENYL-2(3H)FURANONE
Trifluoromethanesulfonic anhydride, 5.5 mL (32.5 mmol.), was added to 14 mL dry methylene chloride under argon at room temperature. The solution was cooled to -40° C. and 2.3 g (22 mmol.) of finely powdered, oven dried Na 2 CO 3 was added. To the stirred mixture 6.7 g (25 mmol.) of 5-(hydroxymethyl)-4,5-dihydro-3,3-diphenyl-2(3H)furanone in 15 mL of methylene chloride was added dropwise, stirring 2 hours at -40° C. before warming to 0° C. for 0.5 hours. The reaction was quenched at 0° C. by adding 10 mL of water dropwise with vigorous stirring. The layers were separated, the organics washed with brine, dried (MgSO 4 ), and evaporated at reduced pressure to a solid. This material was used as received and usually contained 5 to 15% of unreacted alcohol. 1H NMR (CDCl 3 )δ 2.77-2.83 (m, 1H), 3.05-3.14 (m, 1H), 4.51-4.71 (m, 2H), 4.7-4.75 (m, 1H), 7.25-7.45 (m, 10H).
5-[1-(2-N-PROPYLIMIDAZOL)METHYL]-4,5-DIHYDRO-3,3-DIPHENYL-2(3h)-FURANONE HYDROCHLORIDE
5-Trifluoromethanesulfonyloxymethyl-4,5-dihydro-3,3-diphenyl-2(3H)furanone (5.2 g, 13 mmol.) and 3.0 g (28 mmol.) of 2-n-propylimidazole were stirred in 15 mL of methylene chloride under argon in a sealed tube and heated at 120° C. overnight. After the cooled solution was poured onto water, the organics were washed with dilute aqueous K 2 CO 3 , brine, and dried (MgSO 4 ) before exaporation at reduced pressure to give an oil. The resuide was chromatographed (silica, 98: 2, methylene chloride: methanol) to give 3.0 g (64%) of product. This material was dissolved in warm isopropanol, 1 equivalent of 1N hydrochloric acid in ether was added, and the product allowed to crystallize, mp 232°-234° C. 1 H NMR(DMSO-d 6 )δ .905(t, J=7.4 Hz, 3H), 1.63-1.79(m, 2H), 2.79-2.89(m, 1H), 2.95(t, J=7.5 Hz 2H), 3.23-3.33(m, 1H), 4.48-4.70(m, 3H), 7.23-7.43(m, 10H), 7.61(d, J=1.8 Hz, 1H), 7.66(d, J=1.8 Hz, 1H); IR(KBr) 3062, 2957, 2933, 2872, 1761, 1493, 1445, 1277, 1169, 1069, 696 cm -1 ; analytical tlc (silica, 95: 5, methylene chloride: MeOH) Rƒ .39. Anal. calcd. for C 23 H 25 ClN 2 O 2 : C, 69.60; H, 6.35; Cl, 8.93; N, 7.06. Found: C, 69.62; H, 6.37; Cl, 8.97; N, 7.04.
The following compounds were prepared in an analogous manner.
5-[1-(2-Isopropylimidazol)methyl]-4,5-dihydro-3,3-diphenyl-2(3H)furanone hydrochloride (mp 250.5°-252.5° C.),
5-[1-(2-Isobutylimidazolmethyl]-4,5-dihydro-3,3-diphenyl-2(3H)furanone, hydrochloride (mp 223°-27° C.),
5-[1-(2-tert-Butylimidazol)methyl]-4,5-dihydro-3,3-diphenyl-2(3H)furanone hydrochloride hydrate (mp 118°-130° C.),
5-[1-(2-Phenylimidazol)methyl]-4,5-dihydro-3,3-diphenyl-2(3H)furanone hydrochloride (mp 189°-190.5° C.),
5-{1-[2-(2-methoxyethyl)imidazol]methyl}-4,5-dihydro-3,3-diphenyl-2(3H)furanone hydrochloride (mp 236°-237° C.).
EXAMPLE XI
5-[1-(2-ETHYL-3-METHYLIMIDAZOL)METHYL]-4,5-DIHYDRO-3,3-DIPHENYL2(3H)FURANONE CHLORIDE HYDRATE
1-Methyl-2-ethylimidazole (2.5 g, 22 mmol.) and 8.0 g (20 mmol.) of 5-trifluoromethanesulfonyloxymethyl-4,5 -dihydro-3,3-diphenyl-2(3H)furanone were mixed with 15 mL of methylene chloride under argon in a sealed tube and heated 1.2 hours at 100° C. Upon cooling, a solid formed and was filtered. The solvents were evaporated at reduced pressure and the residue and the solid were recrystallized from isopropanol to give 6.5 g (61%) of pure triflate salt. The solid was taken up in 180 mL of methanol and passed through 180 mL of Amberlite IRA-400(Cl). The resulting solid was recrystallized from acetone to give 4.8 g of product, mp 243°-245° C. 1 H NMR(CDCl 3 )δ 1.17(t, J=7.5 Hz, 3H), 2.81-2.91(m, 1H), 3.03-3.14(m, 2H), 3.26-3.34(m, 1H), 3.80(s, 3H), 7.21-7.43(m, 10 H), 7.66(d, J=2.0 Hz, 1H), 7.71(d, J=2.0 Hz, IH); IR(KBr) 3478, 3409, 3108, 3077, 1769, 1531, 1447, 1159, 1061, 964, 753, 704 cm -1 ; analytical TLC (silica, 95: 5, methylene chloride: MeOH) Rƒ.26. Anal. calcd. for C 23 H 25 CIN 2 O 2 .0.05 H 2 O): C, 68.05; H, 6.46; N, 6.90; Cl, 8.73. Found: C, 68.24; H, 6.45; N, 7.10; Cl, 8.97.
5-[1-(2-Isopropyl-3-methylimidazol)methyl]-4,5-dihydro-3,3-diphenyl-2(3H)furanone chloride hydrate was prepared in an analogous manner, mp 156°-159° C.
EXAMPLE XII
5-[1-(2-CARBOMETHOXYIMIDAZOL)METHYL]-4,5-DIHYDRO-3,3-DIPHENYL-2(3H)FURANONE HYDROCHLORIDE
To a stirred solution of 0.11 g (0.87 mmol.) of 2-carbomethoxyimidazole in 5 mL of dimethylformamide, under argon, was added 34 mg (1.5 mmol.) of sodium hydride. The mixture was stirred until solution was completed (about 1 hour) and then 0.5 g (1.2 mmol.) of 5 -(trifluoromethanesulfonyloxymethyl)-4,5-dihydro-3,3 -diphenyl-2(3H)furanone was added. After being stirred for 20 hours, the solution was concentrated in vacuo. The residual semi-solid was partitioned between methylene chloride and water. The organic layer was separated, washed with water, dried over MgSO 4 and concentrated in vacuo. The residue was applied to a preparative TLC plate (silica, 2 mm×20 cm×20 cm) using methanol: methylene chloride (5:95). Elution of the major spot gave 300 mg (91%) of base. To a solution of this material in ethyl acetate was added an equivalent of 1N hydrogen chloride in ether to afford colorless crystals, mp. 151°-152° C. 1 H NMR(CDCl 3 )δ 2.62-2.76(m, 1H), 3.20-3.28(m, 2H), 4.07(s, 3H), 4.65-4.77(m, 2H), 5.14-5.23(m, 1H), 7.22-7.40(m, 10H), 7.56(s, 1H), 7.63(s, IH); IR(KBr) 3432, 2519, 1765, 1745, 1460, 1447, 1270, 1172, 960, 699 cm -1 ; analytical TLC (silica, 96:4, methylene chloride: methanol) Rƒ55. Anal. calcd. for C 22 H 21 ClN 2 O 4 : C, 64.00; H, 5.13; Cl, 8.59; N, 6.78. Found: C, 64.29; H, 5.24; Cl, 8.43; N, 6.56.
The following compounds were prepared in an analogous manner.
5-[(2-Nitroimidazol)methyl]-4,5-dihydro-3,3-diphenyl-2(3H)furanone Hydrochloride (mp 190°-205° C.),
5-[1-(2-Benzylimidazol)methyl]-4,5-dihydro-3,3-diphenyl-2(3H)furanone Hydrochloride (mp 256°-260° C.).
EXAMPLE XIII
6,7-DIHYDRO-1-[(2,3,4,5-TETRAHYDRO-5-OXO-4,4-DIPHENYL-2-FURANYL)METHYL-5H-PYRROLO[1,2-A] IMIDAZOLIUM CHLORIDE
A mixture of 2.0 g (18.5 mmol.) of 6,7-dihydro-5H-pyrrolo[1,2-a]imidazole and 5.0 g (12 5 mmol.) of 5-(trifluoromethylsulfonyloxymethyl)-4,5-dihydro-3,3-diphenyl-2(3H)furanone in 20 mL of methylene chloride under argon in a sealed tube was heated at 100° C. for 20 hours. After being cooled to 25° C., the reaction mixture was washed successively with brine and water, dried over MgSO 4 and concentrated. The residual liquid was chromatographed on 135 g of silica eluting with 98:2 and then 96:4 methylene chloride: methanol to give 4.0 g (63%) of product. This triflate salt in 60 mL of methanol was passed through a column of 150 mL of Amberlite IRA-400 (Cl anion exchange resin). Concentration of the eluate afforded 2.6 g of colorless crystals, mp 245°-246° C. 1 H NMR(CDCl 3 )δ 2.67(dd, J=10.3 Hz, J=13.4 Hz, 1H), 2.78-2.91(m, 2H), 3.42-3.66(m, 3H), 4.24-4.36(m, 2H), 4.37-4.48(m, 1H), 4.82-4.93(m, 1H), 5.41(dd, J=1.7 Hz, J=14.6 Hz, 1H), 7.21-7.43(m, IH), 8.21(d, J=1.8 Hz, 1H); IR(KBr) 3484, 3399, 3093, 3062, 1764, 1553, 1447, 1164, 964, 709 cm -1 ; analytical TLC (silica, 9: 1, methylene chloride: MeOH) Rƒ 0.14. Anal. calcd. for C 23 H 23 ClN 2 O 2 +0.75 H.sub. 2 O: C, 67.64; H, 6.05; N, 6.86; Cl, 8.68. Found: C, 67.71; H, 6.06; N, 6.92; Cl, 8.69.
The following compounds were prepared in an analogous manner.
5,6,7,8-Tetrahydro-1-[(2,3,4,5-tetrahydro-5-oxo-4,4, -diphenyl-2-furanyl)methyl]imidazo[1,2-a]pyridinium chloride hydrate (mp 235.5°-237° C.),
5,6,7,8-Tetrahydro-8-methyl-1-[2,3,4,5-tetrahydro-5-oxo-4,4 -diphenyl-2-furanyl)methyl]imidazo[1,2-a]pyridinium chloride (mp 220°-225° C.),
1-[(2,3,4,5-Tetrahydro-5-oxo-4,4-diphenyl-2-furanyl)methyl]-8-methylimidazo[1,2-a]pyridinium chloride hydrate (mp 232.5-234.5° C.),
1-[(2,3,4,5-Tetrahydro-5-oxo-4,4-diphenyl-2-furanyl)methyl]imidazo[1,2-a]pyridinium chloride hydrate (mp 266°-268° C.).
EXAMPLE XIV
(S)-(+)-2,2-DIMETHYL-1,3-DIOXOLAN-4-METHYL P-TOLUENESULFONATE
To a stirred solution of 490 g (2.57 mole) of p-toluenesulfonyl chloride in 2 L of methylene chloride was added dropwise 391 mL (2.81 mole) of triethylamine. The stirred solution was cooled to 0° C. and 338.2 g (2.56 mole) of (R)-glycerol acetonide was added dropwise. The reaction mixture was stirred at 0° C. for 2 hours and at 25° C. for 20 hours. After the mixture was filtered, the filtrate was washed successively with IN hydrochloric acid, water and a saturated solution of sodium bicarbonate. The methylene chloride solution was then dried over MgSO 4 and concentrated to give 610 g (83%) of a pale yellow liquid. GC analysis on PH5-crosslinked 5% toluene silicone 25 m×0.2 mm×0.11 mm film thickness, Ti 100° C. 3 min, then 15°/min to 300° C., Tr 11.83 min (100%). Optical rotation for 0.171 g diluted to 1.0 mL in 95% ethanol at 22° C. [α]D+4.11°. IR (neat) 2992, 1594, 1365, 1182, 1090, 977, 825 cm -1 . 1 H NMR(CDCl 3 )δ 7.79 (d, 2H), 7.35 (d, 2H), 4.27 (m, 1H), 4.06-3.97 (m, 3H), 3.78-3.73 (m, IH), 2.45 (s, 3H), 1.31 (s, 3H). Anal. calcd. for C 13 H 18 O 5 S: C, 54.53; H, 6.34; S, 11.20 Found: C, 54.51; H, 6.35; S, 11.14.
(S)-(-)-2,2-DIMETHYL-4-IODOMETHYL-1,3-DIOXOLANE
To a solution of 9.6 g (33.4 mmol.) of (S)-(+)-2,2-dimethyl-1,3-dioxolan-4-methyl p-toluenesulfonate in 20 mL of dimethylformamide was added in portions at 45° C., 5.0 g 33.4 mmol.) of sodium iodide. The reaction mixture was stirred at 78° C. for 20 hours. After being cooled to 25° C., the mixture was filtered. To the filtrate was added 200 mL of water and 250 mL of ether. The ether layer was separated, washed successively with 1N hydrochloric acid, water, aqueous sodium bicarbonate and brine. After the solution was dried over MgSO 4 , it was concentrated to afford 2.9 g (83%) of an orange-red liquid. TLC (silica, ethyl acetate: hexane, 1:9) Rƒ 0.38. GC analysis on PH5-crosslinked 5% toluene silicone 25 m×0.2 mm×0.11 mm film thickness, Ti 100° C. 3 min, then 15./min to 300° C., Tr 4.13 min (100%). Optical rotation for 0.036 g of iodide diluted to 2.0 mL in 95% ethanol at 22° C. [α]D-27.0°. IR (neat) 2987, 2869, 1450, 1378, 1252, 1218, 1149, 1059, 845 cm -1 . 1 H NMR(CDCl 3 )δ 4.35-4.23 (m, 1H), 4.17-4.12 (m, 1H), 3.81-3.76 (m, 1H), 3.28-3.23 (m, 1H), 3.17-3.11 (m, 1H), 1.15 (s, 3H), 1.34 (s, 3H)
(R)-(+)-3-[(2,2-DIMETHYL-1,3-DIOXOLANYL)METHYL]-2,2-DIPHENYLPROPIONIC ACID
To a solution of 39.2 g (0.185 mole) of diphenylacetic acid in 100 mL of tetrahydrofuran was added 309 mL (0.463 mole) of a 1.5 M solution of lithium diisopropylamide mono (tetrahydrofuran) in cyclohexane in 300 mL of tetrahydrofuran at 0° C. The resulting mixture was stirred at 25° C. for 30 minutes and then at 70° C. for 1 hour. After being cooled to 0° C., 67.1 g (0.227 mole) of (S)-(-)-2,2-dimethyl-4-iodomethyl-1,3-dioxolane was added dropwise and stirring was continued at 0° C. for 30 minutes and then at 25° C. for 20 hours. The reaction mixture was poured into 800 mL of ice-water and extracted with ethyl acetate. The aqueous part was acidified (pH 4) with 2.5N hydrochloric acid and saturated with sodium chloride. The mixture was extracted with ethyl acetate. After the organic extracts were washed with brine, they were dried (MgSO 4 ) and concentrated to give 44.5 g (74%) of a red oil. 1 H NMR (CDCl 3 )δ 7.38-7.25 (m), 3.95-3.85 (m, 1H), 3.30-3.15 (m, 1H), 2.95-2.90 (m, 1H), 2.35-2.30 (m, 1H), 1.23 (s, CH 3 ), 1.25 (s, CH 3 ).
(R)-(+)-5-HYDROXYMETHYL-4,5-DIHYDRO-3,3-DIPHENYL-2(3H)FURANONE
A solution of 44.5 g (0.136 mole) of (R)-(+)-3-[(2,2-dimethyl-1,3-dioxolanyl)methyl]-2,2-diphenylpropionic acid in 300 mL of methanol and 300 mL of water wa acidified (pH 1) with 6 N hydrochloric acid. After the reaction mixture was stirred at 25° C. for 2.5 hours, it was concentrated in vacuo. The residue was extracted into ether. The ether extracts were washed successively with 10% aqueous sodium bicarbonate and brine, dried (MgSO 4 ) and concentrated to afford 29.1 g (80%) of a yellow liquid. TLC (silica, ethyl acetate: methlene chloride, 1:9) Rƒ 0.40. Optical rotation for 0.038 g diluted to 2.0 mL with 95% ethanol at 23° C. [α]D+54.63°. IR (neat) 3420, 2972, 2860, 1746, 1498, 1448, 1177, 1110, 699, 675 cm -1 . 1 H NMR (CDCl 3 ) δ 7.37-7.24 (m, 1H), 4.52-4.42 (m, 1H), 3.98 (dd, J=2.80 Hz, 1H), 3.69 (dd, J=4.56 Hz, 1H), 3.01-2.85 (m, J=4.13 Hz, J=2.88 Hz, 2H), 2.30 (br s, 1H).
(R)-(+)-5-TRIFLUOROMETHANESULFONYLOXYMETHYL-4,5-DIHYDRO-3,3-DIPHENYL-2(3H)FURANONE
To a solution of 50 g (0.177 mole) of trifluoromethanesulfonic acid anydride in 50 mL of methylene chloride under argon at -60° C. was added 10.1 g (0.095 mole) of sodium carbonate followed by dropwise addition of a solution of 29 g (0.11 mole) of (R)-(+)-5-hydroxymethyl-3,3 -diphenyl-4,5-dihydro-2(3H)furanone in 100 mL of methylene chloride. After being stirred for 2 hours at -60° C. and 1 hour at 0° C., 35 mL of water was added slowly. The organic layer was separated, washed with brine, dried (MgSO 4 ) and concentrated in vacuo to give 37.8 g (88%) of a liquid product. TLC (silica, hexane: ethyl acetate, 7:3) Rƒ 0.51. Optical rotation for 0.185 g of product diluted to 1.0 mL in chloroform at 23° C.: [α]D+48.64°. 1 H NMR (CDCl 3 )δ 7.39-7.24 (m, 10H), 4.71 (dd, J=2.19 Hz, 1H), 4.64-4.60 (m, 1H), 4.59-4.53 (m, 1H), 3.05 (dd, J=5.10 Hz, 1H), 2.81 (dd, J=10.14 Hz, 1H).
(R)-(+)5-[1-(2-ISOPROPYLIMIDAZOL)METHYL]-4,5-DIHYDRO-3,3-DIPHENYL-2(3H)FURANONE
To a mixture of 4.33 g (11 mmol.) of (R)-(+)-5 -trifluoromethanesulfonyloxymethyl-4,5-dihydro-3,3-diphenyl-2(3H)furanone in 30 mL of methylene dichloride was added 2.2 g (20 mmol.) of 2-isopropylimidazole. The mixture was placed under argon in a sealed tube and heated at 110° C. for 20 hours. After being cooled to 25° C., the mixture was washed with 5% aqueous potassium carbonate and brine. The methylene chloride solution was dried (MgSO 4 ) and concentrated in vacuo. The crude residue was purified by flash chromotagraphy (silica gel, 100 g, 40-60 mesh, methanol: dichloromethane, 2:98) to give 3.2 g (82%) of a slightly pale yellow foam. TLC (silica, methanol: dichloromethane, 1:9) Rƒ 0.76. Optical rotation for 0.0156 g diluted to 2.0 mL with 95% ethanol at 23° C. [α]D+36.15°. IR (KBr) 3400, 2975, 2918, 1760, 1495, 1447, 1275, 1170, 962, 699 cm -1 . 1 H NMR (CDCl 3 )δ 7.38-7.18 (m, 10H), 6.92 (d, J=1.2 Hz, 1H), 6.70 (d, J=1.2 Hz, 1H), 4.58-4.52 (m, 1H), 4.28-4.12 (m, 2H), 3.06-2.92 (m, 2H), 2.65-2.54 (m, 2H), 1.34-1.23 (m, 6H).
(R)-(+)-5-[1-(2-ISOPROPYLIMIDAZOL)METHYL]-4,5-DIHYDRO-3,3-DIPHENYL-2(3H)FURANONE HYDROCHLORIDE
To a solution of 2.05 g (5.7 mmol.) of R)-(+)-5-[1-(2isopropylimidazol)methyl]-4,5-dihydro-3,3-diphenyl-2(3H)furanone in 200 mL of ethyl acetate was added 5.7 mL (5.7 mmol.) of a 1 N solution of hydrogen chloride in ether. The crystalline solid (1.92 g, 85%) was filtered, mp 233°-234° C.). Optical rotation for 0.0150 g diluted to 2.0 mL with 95% ethanol at 21° C.: [α]D+20.27°. IR (KBr) 3435, 2499, 1767, 1600, 1180, 753, 700 cm -1 . 1 H NMR (CDCl 3 )δ 7.43 (d, J=1.6 Hz, 1H), 7.37-7.20 (m, 11H), 4.73-4.62 (m, 2H), 4.38-4.28 (m, 1H), 3.41-3.33 (m, 2H), 2.72-7.68 (m, 1H), 1.58-1.47 (m, 6H). Anal. calcd. for C 23 H 24 N 2 O 2 +HCl: C, 69.60; H, 6.35; N, 7.06; Cl, 8.93. Found: C, 69.40; H, 6.31; N, 6.85; Cl, 8.72.
(S)-(-)-5-[1-(2-Isopropylimidazol)methyl]-4,5-dihydro-3,3-diphenyl-2(3H)furanone hydrochloride was obtained from (S)-glycerol acetonide via an analogous sequence.
EXAMPLE XV
2,2-DIPHENYL-4-METHYL-4-PENTENOIC ACID
A solution of diphenylacetic acid (14 g, 66 mmol.) in 150 mL of tetrahydrofuran was stirred at 0° C. under argon while 55.5 mL of a 2.5 M solution of n-butyllithium in hexane was added dropwise. After 15 minutes, 3-chloro-2-methylpropene (6.51 mL, 66 mmol.) was added in one portion. After 10 minutes, 25 mL of 4N hydrochloric acid was added, along with ether (250 mL). The layers were separated, the organic layer was washed with water (2×100 mL), brine (2×100 mL) dried (MgSO 4 ), and filtered. Concentration afforded 20.2 g (99%) of a yellow oil. 1 H NMR (CDCl 3 )δ 7.4-7.2 (m, 10H), 4.7 (s, IH), 4.6 (s, lH), 3.2 (s, 2H), 1.4 (s, 3H).
5-(BROMOMETHYL)-4,5-DIHYDRO-3,3-DIPHENYL-5-METHYL-2(3H)FURANONE
To a stirred mixture of tetrahydrofuran:water (5:1, 100 mL) was added 2,2-diphenyl-4-methyl-4-pentenoic acid (19.5 g, 73 mmol.) and sodium bicarbonate (6.15 g, 73 mmol.). After 30 minutes, bromine (3.7 mL, 73 mmol.) was added dropwise. After stirring 40 minutes, a solution of sodium thiosulfate (3 g) in 50 mL of water was added. Ether (100 mL) was added and the layers separated. The organic layer was washed with brine, dried (MgSO 4 ) and filtered. Concentration afforded a yellow solid. Recrystallization from ethyl acetate afforded 15 g (60%) of a white solid, mp 146°-148° C. IR (KBr) 1766 cm -1 . 1 H NMR (CDCl 3 )δ 7.4-7.2 (m, 10H), 3.4 (m, 3H), 2.9 (d, lH), 1.5 (s, 3H).
5-[1-(2-METHYLIMIDAZOL)METHYL]-4,5-DIHYDRO-3,3-DIPHENYL-5-METHYL-2(3H)FURANONE
5-(Bromomethyl)-4,5-dihydro-3,3-diphenyl-5-methyl-2(3H)furanone (3.0 g, 8.7 mmol.), 2-methylimidazole (1.5 g, 18 mmol.) and dimethylformamide (6 mL) were placed in a sealed tube. The tube was filled with argon, capped and heated at 150° C. for 65 hours. After the solution was cooled, the mixture was partitioned between saturated sodium bicarbonate solution (20 mL) and methylene chloride (100 mL) and the layers separated. The organic layer was washed with water (2×50 mL), then washed with brine and dried (MgSO 4 ). Filtration, followed by concentration, afforded a solid. Recrystallization from ethyl acetate-hexane gave 1.70 g (57%) of a white, crystalline solid, mp 166°-167° C. IR (KBr) 1758 cm -1 . 1 H NMR (CDCl 3 )δ 7.05-6.55 (m, 12H), 3.59 (AB q, J=15.12 Hz, 2H), 2.59 (AB q, J=13.68 Hz, 2H), 2.01 (s, 3H), 0.84 (s, 3H). Anal. calcd. for C 22 H 22 N 2 O 2 0.25 H 2 O: C. 75.28; H, 6.47; N, 7.97. Found: C, 75.30; H, 6.50; N, 7.52.
EXAMPLE XVI
5-METHYL-3,3-DIPHENYL-2(3H)FURANONE AND 5-METHYLENE-4,5-DIHYDRO-3,3-DIPHENYL-2(3H)FURANONE
A stirred solution 22 g (66 mmol.) of 5-bromomethyl4,5-dihydro-3,3-diphenyl-2(3H)furanone and 10.47 mL (70 mmol.) of 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) in 65 mL of benzene was heated at reflux under argon for 20 hours. The resulting mixture was cooled to 25° C. and filtered. To the filtrate was added 150 mL of 10% hydrochloric acid and 200 mL of ether. The organic layer was separated and washed successively with 2N hydrochloric acid, water, a saturated aqueous solution of sodium bicarbonate and water. After being dried over sodium sulfate, the solution was concentrated to give 16.12 g (97%) of a crude liquid. TLC (silica, ethyl acetate) Rƒ 0.64. 1 H NMR (CDCl 3 ) 7.34-7.08 (m), 5.69 (br s, lH), 4.78 (s), 4.41 (m), 3.64 (d), 3.54 (s), 2.08 (s), 2.02 (s). Integration of the NMR spectum and comparison of the ratios of the resonances at 5.69 (vinyl H) and 4.78 (methylene H) showed a product ratio of 70:30 for the unsaturated methyl lactone to the methylene lactone.
5-BROMOMETHYL-3,3-DIPHENYL-2(3H)FURANONE AND 4-BROMO-5-METHYLENE-4,5-DIHYDRO-3,3-DIPHENYL-2(3H)FURANONE
A stirred mixture of 4.30 g (1.7 mmol.) of the crude mixture of 5-methyl-3,3-diphenyl-2(3H)furanone and 5 -methylene-4,5-dihydro-3,3-diphenyl-2(3H)furanone, 4.62 g (2.6 mmol.) of N-bromosuccinimide and 0.05 g of 2,2 1 -azobis(2-methylpropionitrile) in 40 mL of carbon tetrachloride was stirred and refluxed under argon for 20 hours. After being cooled to 25° C., the mixture was poured into 200 mL of water and extracted with ether. The ether extracts were washed with water, dried over sodium sulfate and concentrated to give 6.57 g of a crude liquid. 1 H NMR (CDCl 3 ) 7.4-7.05 (m), 6.26(s), 6.25 (2), 6.09 (s), 5.9 (s), 4.5-4.2 (m), 4.13 (s), 3.62 (d), 2.77 (s), 2.05 (s), 1.72 (2), 1.5 (br m). Examination of the integration of the NMR spectrum revealed a 60:40 ratio of the bromomethyl product and a secondary bromomethylene lactone.
5-[1-(2-ISOPROPYLIMIDAZOL)METHYL]-3,3-FURANONE HYDROCHLORIDE HYDRATE
A mixture of 6.5 g (19 mmol.) of a crude mixture (60:40) of 5-bromomethyl-3,3-diphenyl-2(3H)furanone and 4-bromo-5-methylene-4,5-dihydro-3,3-diphenyl-2(3H)furanone, 3.25 g (29 mmol.) of 2-isopropylimidazole and 1.0 g (9 mmol.) of sodium carbonate in 25 mL of dimethylformamide under argon in a sealed tube was heated at 115° C. for 7 hours and at 80° C. for 20 hours. The mixture was then stirred at 25° C. for 2 days. The mixture was poured into saturated aqueous sodium bicarbonate (75 mL) and extracted with ether. The combined organic layers were washed with saturated sodium bicarbonate, water, and dried over sodium sulfate. Filtration and removal of solvent gave 4.95 g of a dark frothy semi-solid. TLC (silica, ethyl acetate) Rƒ 0.1. Rƒ 0.26, Rƒ 0.35, Rƒ 0.8 with the desired lactone imidazole at Rƒ 0.26.° Column chromatography on Merck (230-400 mesh) silica gel with elution gradient from 9:1 hexane : ethyl acetate to 100% ethyl acetate afforded 0.88 g (13%) of the free base as a sticky brown residue. 1 H NMR (CDCl 3 ) 7.33-7.20 (m, 10H), 7.02 (d, 1H), 6.89 (d, 1H), 5.71 (t, J=1.5, 1H), 4.83 (d, 2H), 3.02-2.97 (m, 1H), 1.79 (s), 1.35-1.21 (m, 6H).
The free base (0.85 g, 2.3 mmol.) was dissolved in 10 mL of hot methanol and diluted with 50 mL of ether. To the warm mixture was added 2.3 mL (2.3 mmol.) of 1N hydrogen chloride in ether. The mixture was allowed to cool and then placed in the freezer overnight. The solids were filtered and washed with ether. The tan solids were dried under vacuum at 100° C. to afford 0.700 g (1.7 mmol.) of the hydrochloride, mp 209°-211.5° C. Solubility [>1 mg/mL in 0.5N HCl and 1 drop of Tween 80 ]. 1 H NMR (DMSO-d 6 ) 7.69 (d, 2H), 7.39-7.21 (m, 10H), 6.64 (s, IH), 5.41 (s, 2H), 3.56-3.44 (m, 1H), 3.36 (br s, H 2 O), 1.26 (d, 6H). IR (KBr) 3412, 3055, 2980, 2936, 2697, 1797, 1600, 1509, 1494, 1448, 1134, 1085, 949, 763, 699 cm -1 . Anal. calcd. for C 23 H 22 N 2 O 2 . HCl . 0.75 H 2 O: C, 69.95; H, 5.87; N, 7.09; Cl, 8.98. Found: C, 67.66, 67.60; H, 6.02, 6.04; N, 6.91; Cl, 8.70. TLC (silica, ethyl acetate) Rƒ 0.40.
5-[1-(2-Ethylimidazol)methyl]-3,3-diphenyl-2(3H)furanone was prepared from 2-ethylimidazole and the bromolactone mixture in an analogous fashion. The base was a tan solid, mp 102°-103° C. after trituration with ether 1 H NMR (CDCl 3 ) 7.4-7.2 (m, 10H), 7.01 (d, lH), 6.95 (d, 1H), 5.7 (s, IH), 4.8 (s, 2H), 2.6 (q, 2H), 1.4 (t, 3H). IR (KBr) 2975, 1794, 1687 cm -1 . Anal. calcd. for C 22 H 20 N 2 O 2 : C, 76.72; H, 5.85; N, 8.13. Found: C, 76.47; H, 5.89; N, 8.09.
EXAMPLE XVII 5-[1-(3-METHYL-2-N-PROPYL)IMIDAZOL]METHYL-4,5-DIHYDRO-3,3-DIPHENYL-2(3H)FURANONE IODIDE
A mixture of 2.75 g (7.6 mmol.) of 5-[1-(2-n-propyl)imidazol]methyl-4,5-dihydro-3,3-diphenyl-2(3H)furanone and 10 mL of iodomethane was heated in a sealed tube for 20 minutes at 120° C. After being cooled to 25° C., excess iodomethane was evaporated under a stream of nitrogen. Trituration of the residual solid with acetone afforded 3.5 g (92%) of the quaternary salt, mp 207°-210° C. 1 H NMR (CDCl 3 )δ .954 (t, J=7.2 Hz 3H) 1.52-1.68 (m 2H), 2.82-2.94 (m, 1H), 2.95-3.08 (m, 2H), 3.26-3.36 (m, 1H), 3.80 (m, 3H), 4.48-4.70 (m, 3H), 7.24-7.44 (s, 10H), 7.64-7.70 (m, 2H); IR (KBr) 3090, 3059, 2982, 2933, 1756, 1226, 1175, 1154, 707, 696 cm -1 ; analytical TLC (silica, 95:5, methylene chloride: MeOH) Rƒ .15. Anal. calcd. for C 24 H 27 IN 2 O 2 : C, 57.38 H, 5.41; I, 25.25; N, 5.57. Found: C, 57.46; H, 5.43; I, 25.16; N, 5.56.
The following quaternary salts were prepared in an analogous manner.
5-[1-(2-Isopropyl-3-methylimidazol)methyl]-4,5-dihydro-3,3-diphenyl-2(3H)furanone Iodide Hydrate (mp 216°-217° C.)
5-[1-(2-Ethyl-3-methylimidazol)methyl]-4,5-dihydro-3,3-diphenyl-2(3H)furanone Iodide Hydrate (mp 219.5°-221° C.),
5-[1-(2-tert-Butyl-3-methylimidazol)methyl]-4,5-dihydro-3,3 -diphenyl-2(3H)furanone Iodide Hydrate (mp 213°-214.5° C.),
5-[1-[2-(2-Methoxyethyl)-3-methylimidazol]methyl]-4,5 -dihydro-3,3-diphenyl-2(3H)furanone Iodide Hydrate (mp 179°-183° C.).
EXAMPLE XVIII
ANTIMUSCARINIC TEST PROTOCOL
This protocol was designed to identify compounds that possess antagonist activity at postsynaptic muscarinic cholinergic receptors on intestinal (ileal-longitudinal) smooth muscle and bladder detrusor muscle.
PREPARATION OF ILEUM FOR TESTING
Male albino guinea pigs are killed by decapitation or cervical dislocation. The cavity is opened and the small intestine is removed, with about 10 cm of the terminal ileum being discarded. The intestine is placed in a Petri dish that contains Tyrodes solution (137 mM NaCl, 2.7 mM KCl, 1.8 mM CaCl 2 .2H 2 O, 1.1 mM MgCl 2 .6H 2 O, 0.4 mM NaH 3 PO 4 , 11.8 mM NaHCO 3 , 5.6 mM dextrose) and cut into 3-4 cm segments. The segments are preferentially taken from the aboral end of the ileum. Each segment is carefully stretched onto a glass rod 6 mm in diameter and the remaining mesenteric tissue is cut away. The longitudinal muscle, with the myenteric plexus attached, is separated from the underlying circular muscle by gently stroking with a cotton-tipped applicator soaked in Tyrodes solution on a tangent away from the shallow longitudinal incisions made parallel to the mesenteric attachment. Using gentle traction, and taking care to keep the segment moist throughout the whole procedure, the tissue is stripped from the whole length of the segment (Paton and Zar, J. Physiol. 194:13, 1968).
Tissues are suspended with 5-0 silk suture in 10 mL water-jacketed glass tissue baths containing Tyrodes solution maintained at 37° C. and aerated with 95% O 2 /5% CO 2 . The suture connects each tissue to an isometric force-displacement transducer (Grass or Gould) coupled to a physiograph. Each preparation is suspended under a resting tension of 0.3 g and allowed to equilibrate for 36 minutes. During this period, the baths are emptied and filled every 12 minutes with 10 mL of warm Tyrodes solution. At the end of this equilibration period, each muscle strip is conditioned by adding 10 μM carbachol to the baths. The drug remains in contact with each tissue for 1-2 minutes and then is removed from the bath with 4 rapid rinses of 10 mL of warm Tyrodes solution. The preparations are allowed to recover for an additional 12 minutes before being used in experiments.
PREPARATION OF BLADDER FOR TESTING
Male albino guinea pigs are killed by decapitation or cervical dislocation. The peritoneal cavity is opened and the bladder is held lightly at its apex, stretched gently, and fat is lifted with fine forceps and dissected away in situ with blunt-tipped scissors as close to the surface of the bladder as possible. The tissue is placed in a latex-bottomed Petri dish that contains a modified Krebs solution (133 mM NaCl, 1.3 mM NaH 3 PO 4 , 16.3 mM NaHCO 3 , 4.7 mM KCl, 0.6 mM MgSO 4 .7H 2 O, 2.5 mM CaCl 2 .2H 2 O, 7.7 mM dextrose) and cut above the neck. The bladder is collapsed into a flat pouch, which is opened by two lateral incisions and unfolded to give a rectangular sheet of tissue approximately 2 cm long and 1 cm wide. The sheet is gently stretched and pinned to the bottom of the Petri dish. Blunt separation of the mucosa, which is visible as a looser superficial pink layer, is started at one end by carefully inserting the blades of micro dissecting scissors between the mucosa and muscle layers and using gentle spreading of the blades, together with steady traction with forceps to tease the two layers apart. Clean removal of the mucosa is usually possible without any fraying or tearing of the underlying muscle. The removal of the mucosa is considered essential for improving oxygen supply to the preparation and for providing better access on both sides of the thin muscle sheet for administered drugs (Ambache and Zar, J. Physiol. 210:671, 1970). The sheet is trimmed, if necessary, and cut longitudinally into four strips.
The strips are tied off with 5-0 silk suture and are then suspended in 10 mL water-jacketed glass tissue baths containing the Krebs solution maintained at 35° C. and aerated with 95% O 2 /5% CO 2 . The suture connects each tissue to an isometric force-displacement transducer (Grass or Gould) coupled to a physiograph. Each preparation is suspended under a resting tension of 0.5 g and allowed to equilibrate for 36 minutes. During this period, the baths are emptied and filled every 12 minutes with 10 mL of warm Krebs buffer. At the end of this period, each muscle strip is conditioned by adding 10 μM carbachol to the baths. The drug remains in contact with each tissue for 1-2 minutes and then is removed by four rapid rinses of 10 mL of warm Krebs buffer. The preparations are allowed to recover for an additional 12 minutes before being used in experiments.
PREPARATION OF AGONIST
Carbachol is dissolved in saline to produce 2×10 -2 M stock concentrations. Serial dilutions (1:10) in saline or water are made from the stock solution. Appropriate volumes of these solutions are added cumulatively to the 10 mL tissue baths in order to obtain the desired bath concentrations.
PREPARATION OF TEST COMPOUNDS
Compounds that are soluble in water or saline are dissolved in these solvents to produce 2×10 -2 or 2×10 -3 M stock concentrations. Small amounts of IN HCl, NaOH, or 95% ethanol may be added for those agents that are not soluble in water or saline alone. Serial dilutions (1:10) in saline or water are made from the stock solution. Compounds that are insoluble in aqueous solvents are dissolved in dimethylsulfoxide (DMSO) to produce 4×10 -2 M stock solutions. Serial dilutions (1:10) in water are made from the stock solution. Other solvents may be used when appropriate and will be specifically described in the experimental procedure. Appropriate volumes are then added to the baths in order to obtain the desired bath concentrations.
EXPERIMENTAL PROCEDURE
Appropriate volumes of carbachol solutions are cumulatively added to the 10 mL tissue baths to increase the concentration of carbachol in the bath step-by-step without washing out after each single dose. With each concentration step, the tissue contracts isometrically. The next concentration is added only after the preceding contraction has reached a steady value. When the next concentration step does not cause a further decrease in contraction, it is assumed that the maximum effect has been obtained. The tissue is then washed with 4 rapid rinses of 10 mL of warm Tyrodes solution and allowed to recover for 12 minutes [Van Rossum et al.. Arch. Int. Pharmacodyn. 143:240, (1963) and 143:299, (1963)]. Antagonism of carbachol responses in the presence of antagonist are determined by repeating the cumulative addition procedure after the tissue has been exposed to the agonist for 5 minutes.
Three of four different concentrations of antagonist are studied in the same preparations. Responses are expressed relative to the maximum contraction elicited by carbachol in the absence of antagonist. The data are collected via Buxco Data Logger and analyzed by Branch Technology's software package to obtain Kb values for the antagonists.
EXAMPLE XIX
PRIMARY IN VIVO BRONCHODILATOR ASSAY FOR MUSCARINIC ANTAGONISTS
Male Guinea pigs were anesthetized by urethane. The trachea, carotid artery and jugular vein were cannulated. Animals were ventilated with room air at a constant rate and volume. Airway pressure was measured from a side port of the tracheal catheter, and blood pressure and heart rate were monitored as well.
After a stable baseline period, an aerosol of carbachol was administered via an ultrasonic nebulizer. Once the bronchoconstrictor response plateaued, test compound was given in increasing i.v. doses to cause graded, cumulative reductions in airway pressure. If more than a 50% reversal of bronchoconstriction occurred, an ED 50 value for bronchodilator potency was calculated using a probit analysis. The ED 50 was defined as the cumulative i.v. dose that caused a 50% reversal of bronchoconstriction.
__________________________________________________________________________ Muscarinic Antagonist Bronchodilator Activity Activity Ileum Bladder ED.sub.50,Compound Kb, nM Kb, nM mg/kg, i.v.__________________________________________________________________________5-[(1-Imidazol)methyl]-4,5- 373 -- --dihydro-3,3-diphenyl-2(3 .sub.-- H)furanone5-[1-(2-Methylimidazol)methyl]- 107 238 5.54,5-dihydro-3,3-diphenyl-2(3 .sub.-- H)furanone5-[1-(2-Ethylimidazol)methyl]- 68 86 4.04,5-dihydro-3,3-diphenyl-2(3 .sub.-- H)furanone hydrochloride5-[1-(3-Methylimidazol)methyl]- 322 151 1.04,5-dihydro-3,3-diphenyl-2(3 .sub.-- H)furanone bromide hydrate5-[1-(2,3-Dimethylimidazol)- 71 -- 0.85methyl]-4,5-dihydro-3,3-diphenyl-2(3 .sub.-- H)furanone bromide5-[1-(2-Isopropylimidazol)methyl]- 30 33 0.834,5-dihydro-3,3-diphenyl-2(3 .sub.-- H)-furanone hydrochloride5-[1-(2- -n-Propylimidazol)methyl]- 21 70 1.34,5-dihydro-3,3-diphenyl-2(3 .sub.-- H)-furanone hydrochloride5-[1-(2-Methyl-3-benzylimidazol)- 544 -- --methyl]-4,5-dihydro-3,3-diphenyl-2(3 .sub.-- H)furanone bromide5-[1-(2- -n-Butylimidazol)methyl]- 113 -- >104,5-dihydro-3,3-diphenyl-2(3 .sub.-- H)furanone5-[(1-Benzimidazol)methyl]-4,5- 1281 -- --dihydro-3,3-diphenyl-2(3 .sub.-- H)furanone5-[1-(Ethylimidazol)methyl]- 229 -- --4,5-dihydro-3,3-diphenyl-2(3 .sub.-- H)furanone bromide5-[1-(2-Ethylimidazol)methyl]- 8.2 -- 1.93,3-diphenyl-2(3 .sub.-- H)furanone5-[1-(2-Ethyl-4-methylimidazol- 86 -- --methyl]-4,5-dihydro-3,3-diphenyl-2(3 .sub.-- H)furanone hydrobromide5-[1-(3-Methyl-2- -n-propylimidazol- 23 11 0.11methyl]-4,5-dihydro-3,3-diphenyl-2(3 .sub.-- H)furanone iodide5-[1-(3-Methylimidazol)methyl]- 370 317 --4,5-dihydro-5-methyl-3,3-diphenyl-2(3 .sub.-- H)furanone hydrate5-[1-(2-Isopropyl-3-methylimidazol- 2.9 0.7 0.007methyl]-4,5-dihydro-3,3-diphenyl-2(3 .sub.-- H)furanone bromide5-[1-(2-Ethyl-3-methylimidazol)- 8 5 0.13methyl]-4,5-dihydro-3,3-diphenyl-2(3 .sub.-- H)furanone bromide -S)-(-)-5-[1-(2-Ethylimidazol)- 169 350 --methyl]-4,5-dihydro-3,3-diphenyl-2(3 .sub.-- H)furanone hydrochloride( .sub.-- R)-(+)-5-[1-(2-Ethylimidazol)- 21 129 --methyl]-4,5-dihydro-3,3-diphenyl-2(3 .sub.-- H)furanone hydrochloride5-[1-(2-Isobutylimidazol)methyl]- 489 -- >104,5-dihydro-3,3-diphenyl-2(3 .sub.-- H)-furanone hydrochloride5-[1-(2-tert-Butylimidazol)- 3.3 -- 0.14methyl]-4,5-dihydro-3,3-diphenyl-2(3 .sub.-- H)furanone hydrochloride5-[1-(4-Phenylimidazol)methyl]- 140 -- Insol.4,5-dihydro-3,3-diphenyl-2(3 .sub.-- H)-furanone hydrochloride hydrate5-[1-(2-Phenylimidazol)methyl]- 5920 -- >64,5-dihydro-3,3-diphenyl-2(3 .sub.-- H)-furanone5-[1-[2-(2-Methoxymethyl)- 67 -- >10imidazol]methyl]-4,5-dihydro-3,3-diphenyl-2(3 .sub.-- H)furanonehydrochloride hydrate6,7-Dihydro-1-[(2,3,4,5- 33 -- 0.7tetrahydro-5-oxo-4,4-diphenyl-2-furanyl)methyl]-5 .sub.-- H-pyrrolo-[1,2-a]imidazolium chloride hydrate5-[1-(2-Ethoxymethylimidazol)- >1000 -- >10methyl]-4,5-dihydro-3,3-diphenyl-2(3 .sub.-- H)furanone5-[(1,8-Diazabicyclo[5.4.0]undec- >1000 -- >107-en-8-yl)methyl]-4,5-dihydro-3,3-diphenyl-2(3 .sub.-- H)furanone chloridehydrate5-[1-(2-Isopropyl-3- 4 2.4 0.06methylimidazol)methyl]-4,5-dihydro-3,3-diphenyl-2(3 .sub.-- H)furanoneiodide5-[1-(Ethoxymethyl-3- 253 339 >10methylimidazol)methyl]-4,5-dihydro-3,3-diphenyl-2(3 .sub.-- H)furanone iodide5-[1-(2-Isopropylimidazol)methyl]- 31 -- --3,3-diphenyl-2(3 .sub.-- H)furanonehydrochloride hydrate5-[1-(2-Methoxyethylimidazol)- 638 -- >10methyl]-4,5-dihydro-3,3-diphenyl-2(3 .sub.-- H)furanone hydrochloride5-[1-(2-Methoxymethyl-3- 40 -- --methylimidazol)methyl]-4,5-dihydro-3,3-diphenyl-2(3 .sub.-- H)furanoneiodide5-[1-(2-Methoxyethyl-3- 39 -- --methylimidazol)methyl]-4,5-dihydro-3,3-diphenyl-2(3 .sub.-- H)furanoneiodide hydrate5-[1-(2-Carbomethoxyimidazol)- 435 -- --methyl]-4,5-dihydro-3,3-diphenyl-2(3 .sub.-- H)furanone hydrochloride1-[(2,3,4,5-Tetrahydro-5-oxo- 45 -- --4,4-diphenyl-2-furanyl)methyl]-imidazo[1,2-a]pyridinium chloridehydrate( .sub.-- R)-(+)-5-[1-(2- 10 15 --Isopropylimidazol)methyl]-4,5-dihydro-3,3-diphenyl-2(3 .sub.-- H)furanonehydrochloride1-[(2,3,4,5-Tetrahydro-5-oxo-4,4- 74 -- --diphenyl-2-furanyl)methyl]-8-methylimidazo[1,2-a]pyridiniumchloride hydrate5-[1-(2-Benzylimidazol)methyl]- 223 -- --4,5-dihydro-3,3-diphenyl-2(3 .sub.-- H)-furanone hydrochloride5,6,7,8-Tetrahydro-1-[(2,3,4,5- -- -- --tetrahydro-5-oxo-4,4-diphenyl-2-furanyl)methyl]imidazo[1,2-a]-pyridinium chloride hydrate__________________________________________________________________________ | Furanone compounds and compositions having anticholinergic activity are described. The compounds have the formula: ##STR1## wherein: the dashed line indicates either the 4,5-unsaturated or the 4,5-dihydrofuranone ring;
R 1 and R 2 may be the same or different and are hydrogen, thienyl, furanyl, or cycloalkyl (C 3 -C 6 ), benzyl, phenyl, substituted phenyl or substituted benzyl wherein the phenyl or benzyl group may be substituted with halogen, trifluoromethyl, lower alkyl, lower alkoxy or hydroxy;
R 3 , R 4 and R 5 may be the same or different and are hydrogen, lower alkyl, lower alkyl substituted with a halogen, alkoxy, amino or carboxylic acid group, an alkyl or alkylene bridge between R 4 and R 5 or R 3 and the ring N, trifluoromethyl, nitro, a cycloalkyl group containing 3 to 6 carbons, halogen, benzyl, phenyl, substituted phenyl or substituted benzyl, for which the substituents are the same as those set forth for R 1 and R 2 substituted benzyl or phenyl.
R 6 in the dihydrofuranone series is hydrogen or lower alkyl.
Also described are the pharmaceutically acceptable quaternary alkyl and acid addition salts of such compounds. The compounds are particularly useful in the treatment of neurogenic bladder disorder and chronic obstructive pulmonary diseases. | 2 |
CROSSREFERENCE TO A RELATED APPLICATION
Priority of German Pat. application No. P 24 47 190.7 filed Oct. 3, 1974 is claimed under the Convention.
FIELD OF THE INVENTION
A crank and drive mechanism for a raisable sliding top of a motor vehicle, with a crank arm carrying a crank button and mounted on a rotary hub, the crank arm being retractable into a dish-shaped holding recess, in which structure the hub is coupled in a rotation-proof manner to a shaft, connected by means of a pair of gear-wheels, with a shaft carrying a driving pinion for the top-sliding mechanism.
DESCRIPTION OF THE PRIOR ART
In crank drives of the prior art a crank arm can be retracted only into the holding recess when it is located in a very specific position. In normal sliding tops this disadvantage is unimportant because the operation brings the sliding top into a position in which the crank arm can be retracted into the holding recess, since one crank rotation, which is the maximum necessary to bring the crank arm into the position of retractability, causes a justifiable displacement of the sliding top. In the case of a raisable sliding top, the above described situation is the same with regard to the top displacement but not with regard to the top extension. Since for the extension of the top there is provided only a relatively limited rotary movement of the crank arm, for example of a total of two rotations, only very few and in the example indicated only two positions of the raised top are available in which the crank arm can be retracted into the holding recess.
SUMMARY OF THE INVENTION
The objects of the invention are:
TO PROVIDE A CRANK-AND-DRIVE-MECHANISM FOR A RAISABLE SLIDING TOP OF THE TYPE DESCRIBED WHOSE CRANK ARM CAN BE RETRACTED INTO A HOLDING COUNTERSUNK RECESS IN A PLURALITY OF POSITIONS OF THE RAISED TOP;
TO PROVIDE FOR THE EXTENSION MOVEMENT OF THE TOP AN ADDITIONAL GEARING STAGE IN THE CRANK AND PINION WHICH ACTS AS A REDUCTION GEAR AND MEANS TO CONNECT IT IN THIS GEARING STAGE WHEN THE ROOF TOP IS IN THE CLOSED POSITION; AND
TO PROVIDE, FOR THE TOP EXTENSION MOVEMENT A GEAR FOR REDUCING THE CRANK MOVEMENT, WHICH IS PRACTICALLY LIMITED ONLY BY SPACE CONDITIONS AND WHICH PERMITS, FOR EXAMPLE, FIVE OR MORE ROTATIONS OF THE CRANK FOR THE COMPLETE EXTENSION OF THE TOP.
Since after each rotation the crank arm comes into a position where it can be retracted, the crank arm can in this example be retracted in five positions of the top so that only a relatively slight change in the raised top position is necessary to reach a retracted position.
Another object of the invention is to provide a gearing stage which is substantially self-locking so that the sliding top remains fixed in any lift position without requiring a special locking device.
In a preferred embodiment of the invention, the shaft on which the crank is mounted is longitudinally displaceable and has two fixed gear-wheels each with a different number of teeth. The shaft carrying the pinion has also two fixed gear-wheels with different numbers of teeth. Depending on the axial position of the shaft connected to the crank hub, the gear-wheel having the smaller number of teeth engages with the gear-wheel on the crank shaft having the larger number of teeth or the gear-wheel having the larger number of teeth engages with the gear-wheel on the crank hub shaft having the smaller number of teeth.
The longitudinal displacement of the shaft can be achieved by the device that the crank arm is mounted on the hub so as to pivot about an axis other than its center of rotation and has an extension co-operating with a recessed section on the crank hub shaft for the purpose of displacing the said shaft by pivoting the crank arm. Advantageously a spring is provided which keeps the crank hub shaft in a position in which the reduction gear is disengaged.
To obtain an end stop for the crank mechanism with the top in terminal positions, either fully retracted or with the top fully extended, a gear-wheel fixed to the crank hub shaft is provided to be in engagement by means of at least one intermediate wheel, with a ratchet wheel that has a concentric connecting link slot engaged by a pin rotatable on the crank shaft but axially displaced therewith, in which structure the transmission ratio between thia second gear-wheel and the ratchet wheel, as well as the length of the connecting link slot are dimensioned in such a manner that the pin abuts against one end of the connecting link slot when the sliding top is fully retracted and open and against the other end of the said link slot when the top is fully extended.
To maintain a stop for the sliding top that is releasable without additional operational elements in its locked position, the connecting link slot may have two sections whereof one extends from one end to a point at which the pin is located with the sliding top fully closed, and the other extends from this point to the other end of the connecting link slot, while the second section and the pin are constructed in such a way that the latter can only enter the second section after a displacement of the crank hub shaft for the purpose of connecting in the reduction gear stage.
Further details and characteristics of the invention can be learned from the following description in conjunction with the drawings which show a basic embodiment of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
There are shown in
FIG. 1, a section through a crank and drive mechanism according to the invention in the position in which the sliding top has been extended by rotation of the crank arm;
FIG. 2, a section along the line 2 -- 2 in FIG. 1;
FIG. 3, a diagrammatical representation of the gear-wheels of the gear shown in FIG. 1;
FIG. 4, a section along the line 4 -- 4 in FIG. 3;
FIG. 5, a section along the line 5 -- 5 in FIG. 3;
FIG. 6, a diagrammatical representation of a vehicle top with the sliding top in the closed position; and
FIG. 7, a representation as in FIG. 6 but with the sliding top extended.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
In the embodiment shown the sliding top 1 is both slid and pivoted by a compression resistant cable 2, via a crank mechanism 3. The cable 2 is fixed to a transport bridge 4 supporting a lever mechanism 5 which is on the one hand connected with sliding top 1 and on the other is guided in a not shown connecting link guide at 6. Raisable sliding tops of this type are known to the art.
The crank and drive mechanism for the sliding top 1 is shown in detail in FIGS. 1 to 5. It has a driving pinion 7 whose external toothing engages with cable 2, which is compression-resistant and which is mounted on a shaft 8 pivotably supported in gear box 9. The cable and pinion connection is similar to that in U.S. Pat. No. 3,976,325, issued Aug. 24, 1976, by inventor Walter Schaetzler, assignor to Webasto-Werk W. Baier KG, of common ownership with this application. The gear box 9 is screwed to a portion 10 of the fixed top section. A crank arm 11 which is pivotably mounted at 12 on a rotary hub 13 serves to drive the pinion 7. A hub 13 is connected in a non-rotary but axially displaceable manner with a shaft 14 which is mounted on the one hand in gearbox 9 and on the other hand in hub 13. The hub is mounted pivotably in a cover plate 15. The driving connection between the shaft 14 and the pinion shaft 8 is established via pairs of gear-wheels 16, 17, or 18, 19 which can be connected alternately in a manner to be described hereinafter. The gear-wheels 16 and 18 are rigidly connected with the shaft 8, and the gear-wheels 17 and 19 are rigidly connected with the shaft 14. In this embodiment the transmission ratio of the gear-wheels 16, 17 is 1:1, and that of gear-wheels 18, 19 is 4:1. The gear-wheels 17 and 19 can engage alternately with gear-wheels 16 and 18 as a result of axial displacement of shaft 14.
The shaft 14 is under the action of a spring 20 which attempts to pull this shaft upward as shown on FIG. 1. Thereby the gear-wheel 17 engages with the gear-wheel 16. In this position the sliding top is slid by the rotating crank arm 11, from its closed position under the fixed top section or is brought back from the open position into the closed position. When the sliding top is to be extended or raised from the closed position, the shaft 14 in FIG. 1 is moved downward so that the gear-wheels 16 and 17 are disengaged and the gear-wheels 18 and 19 are engaged. This position is shown on FIG. 1. The shaft 14 is displaced by the pivoting crank arm 11 upward into the fully extended position of FIG. 2 whereby it seizes with an extension 21 a recessed section 22 at the lower end of the shaft 14 and pulls this shaft downward against the action of spring 20. As can be seen in FIG. 2, a holding recess 23 is provided in the inner top layer into which the crank arm 11 can be folded. By means of the reduction gearing produced by the size of gear-wheels 18 and 19, the folding of the crank arm 11 can take place in a plurality of positions of the raised sliding top.
To obtain a stop for the crank arm in the fully opened position, in the closed position, and in the fully extended position of the sliding top, a ratchet wheel 25 is provided in the gearbox which engages via a pinion 26 with a gear-wheel 27 fixed on the shaft 14. In the ratchet wheel 25 a connecting link slot 28 is provided which is engaged by a pin 29 fixed to a plate 30, the latter being rotatably mounted on shaft 14. It is, however, secured against displacement relative to the shaft 14 by a spring ring 31. The transmission ratio between the gear-wheel 27 and the ratchet wheel 25, as well as the length of the connection link slot 28 are dimensioned in such a way that pin 29 abuts against one end 32 of the connecting link slot when the sliding top 1 is fully slid back, and open, and against the other end 33 of the said slot when the sliding top is fully exposed or closed. To enable the user to determine when the sliding top is in its closed position, the connecting link slot is subdivided into two portions 34 and 35 and the pin 29 can slide, in the link slot portion 34 only, with its thickened end 36 in the normal displacement position of the crank mechanism. This is in the position of the shaft 14 in which the gear wheels 16 and 17 are engaged. With the sliding top closed, the pin 29 abuts with its thickened end 36 against the end 37 of the connecting link slot portion 34. When then the crank arm 11 is pivoted upward so as to extend the sliding top as is shown on FIG. 2, then, in the manner described above, the shaft 14 is moved downward and by means of plate 30 carries the pin 29 with it, which as a result can enter the link slot portion 35. On rotating crank 11 for the purpose of extending the sliding top 1, the ratchet wheel 25 also rotates until pin 29 abuts against the end 33 of link slot portion 35. In this position the sliding top is fully extended.
By this arrangement the sliding top can be raised only from its closed position because only in this position the pin 29 can change from the one connecting link slot section 34 into the other connecting link slot section 35. This changeover is made possible by a bore 40 which interconnects the two connecting link slot sections 34 and 35 and is arranged in a position that corresponds to the closed position of the sliding top 1. Thus the plate 30 which carries the pin 29 is prevented from rotating in this embodiment, by being traversed by the spindle 41 of the ratchet wheel 25.
As can be seen in FIG. 3, gear-wheel 27 has only one pair of teeth 27a so that the ratchet wheel 25 can be advanced only once during each rotation of the gear-wheel 27. Thereby the large transmission ratio relative to ratchet wheel 25 which would be necessary with a complete toothing of gear wheel 27 is avoided. Such drives are employed for the purpose of driving tachometers.
FIG. 2 shows the locked setting of the crank arm in its three positions namely the extended position, drawn in full lines in FIG. 2 for raising the top, in the position 11a for the normal displacement of the top and in the retracted position 11b, both shown in dotted lines in FIG. 2. It comprises two blocking members 51 held apart by a spring 50 and positioned in crank arm 11, which blocking members cooperate with corresponding recesses 52, 52a and 52b in the corresponding positions of the crank arm 11. The recesses 52, 52a and 52b are positioned in stop plates 53 inserted in the crank hub 13.
The apparatus of the invention renders superfluously an independent locking system for the sliding top, particularly in an extended position, since the gear consisting of gear-wheels 18 and 19 is self-locking and a further locking is provided by crank arm 11 after being folded into the holding recess 23.
Thus, unlike the known crank and drive mechanism for a raisable sliding top, the invention also makes it possible to solve the problem of carrying out all operations for the actuation of the sliding top, namely the sliding, the extending and the release of the locking system in the closed position so as to permit the extending movement with a single operating member, namely the crank arm. The closed position of the top when it is retracted from the open position is indicated automatically to the operator, namely by the aforementioned abutment of pin 29 against the end 37 of the connecting link slot section 34. For extending the top the operator merely has to pivot the crank arm 11 upward, whereby the reduction gear stage 18, 19 is connected in. The end of the extension movement is indicated by the abutment of pin 29 against the end 33 of the connecting link slot section 35. When the sliding top is retracted from its extended position into the closed position, the pin 29 abuts against the wall of bore 40 on reaching the closed position. The crank arm 11 permits then no further rotation since the pin 29 cannot move out of the connecting link section 35 because, due to the locking of the crank arm 11 in the up-tilted position, the shaft 14 cannot be displaced upward.
Obviously numerous modifications of the embodiment shown are conceivable without exceeding the scope of the invention. Thus, it is possible to use instead of the gear wheel 27, one of the gear-wheels 17, 19 for driving the ratchet wheel 25 and to provide a second gearing stage. Furthermore, the axial displacement of the shaft 14 can be achieved by means other than by pivoting the crank arm 11. | A crank and drive mechanism for a raisable sliding top such as of a motor vehicle is provided with a crank arm, with a mechanism to permit a plurality of rotations to said crank arm for a complete extension and retraction of the top, including an end stop.
Means are provided to permit, with a single operating member, the actuation of the top into sliding movements, closing movements, opening movements, locking it in a position established, maintaining the top in a locked position releasably without the necessity for additional parts and automatically indicating the closed and the open positions of the top. | 8 |
BACKGROUND OF THE INVENTION
[0001] The present invention is generally related to purge control devices, and, more particularly, to a unibody electromagnetic valve for controlling the flow of fuel vapors. The invention is further related to valve-constructing techniques that enable to produce a valve with low acoustic noise and reduced permeability relative to the fuel vapors passing through the valve.
[0002] Environmental regulations for automotive-related emissions have been evolving over the years to more rigorously prescribe the levels of emissions that may be discharged into the atmosphere, such as fuel vapors that may accumulate in the fuel tank of an automobile. Accordingly, evaporative systems for reducing the discharge of these vapors into the atmosphere have to accurately meet such regulations. At the same time, the evaporative systems should be reliably and affordably constructed to enable suppliers in the automotive industry to successfully compete in the marketplace.
[0003] Known purge control devices generally use an assembly of many discrete parts, which incrementally add to the cost and weight of the device and tend to adversely impact the overall reliability of the device. FIG. 1 illustrates one known purge control device 10 including a solenoid valve 12 having a relatively heavy plunger 14 . The valve may operate using pulse width modulation (PWM) techniques at a preset frequency, such as 16 Hz. Although the valve provides appropriate flow control to the fuel vapors that pass therethrough, this type of valve may generate objectionable levels of acoustic noise during its operation. Most customers view low noise as a desirable feature in automotive applications, and, consequently, the ability to provide a valve that in operation has low levels of acoustic noise is a very desirable feature for suppliers of automotive components, such as the assignee of the present invention.
[0004] The body of a valve, such as that illustrated in FIG. 1, is generally made from plastic, and it is known that there might be some diffusion of fuel vapors through the body of the valve. The level of this diffusion is relatively low and this has not been an issue in view of present environmental regulations. However, it is anticipated that there may be requirements that may be enacted in the future that would mandate eliminating or substantially reducing the levels of such a diffusion.
[0005] In view of the foregoing considerations, it would be desirable to provide a valve, such as may be used in a purge control device, that in operation produces relatively low levels of acoustic noise. It would be further desirable to provide a valve made of materials with reduced permeability relative to the fuel vapors passing through the valve. It would be further desirable to provide a valve with fewer parts relative to the number of parts traditionally used in the industry so as to enable incremental cost and weight savings as well as improved reliability.
BRIEF SUMMARY OF THE INVENTION
[0006] Generally, the present invention fulfills the foregoing needs by providing in one aspect thereof, a valve for a purge control device. The valve includes an integral body. The valve further includes a resilient member inserted into the integral body. The resilient member is electromagnetically responsive so that the member can be selectively actuated between respective open and close conditions. An electromagnetic actuator is affixed to the integral body to generate an electromagnetic field for selectively actuating the resilient member between the open and closed conditions. The mass of the resilient member is sufficiently low so that the level of noise produced by the valve is correspondingly low.
[0007] In another aspect thereof, the present invention further fulfills the foregoing needs by providing a method for constructing a valve for a purge control device. The method allows constructing an integral body. The method further allows inserting a resilient member into the integral body. The resilient member is electromagnetically responsive so that the member can be selectively actuated between respective open and close conditions. An electromagnetic actuator is coupled to the integral body to generate an electromagnetic field for selectively actuating the resilient member between the open and closed conditions. The mass of the resilient member is sufficiently low so that the level of noise produced by the valve is correspondingly low.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] The features and advantages of the present invention will become apparent from the following detailed description of the invention when read with the accompanying drawings in which:
[0009] [0009]FIG. 1 illustrates one known purge control device to assist the reader understand some of the problems which are overcome in accordance with aspects of the present invention.
[0010] [0010]FIG. 2 is a cross-sectional view of one exemplary embodiment of a unibody purge valve embodying a reed valve in accordance with aspects of the present invention.
[0011] [0011]FIG. 3 is a cross-sectional view of another exemplary embodiment of a unibody purge valve embodying a diaphragm valve in accordance with other aspects of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0012] [0012]FIG. 2 is a cross-sectional view of one exemplary embodiment of a unibody purge valve 100 embodying aspects of the present invention. As used herein the expression “unibody” refers to an integral structure for the body of the valve, as opposed to a multi-part body. As shown in FIG. 2, valve 100 includes a normally closed reed 102 that may deflect to an open condition, represented by reed position 103 , in response to an appropriate voltage signal connected to an associated electromagnetic reed actuator 104 , such as may be made up of an armature 106 and a winding 108 . Purge valve 100 , in response to the voltage signal applied to actuator 104 , allows to selectively communicate an inlet port 110 with an outlet port 112 through an opening 114 . In one exemplary embodiment the inlet port may be connected to a canister port, and the outlet port may be connected to the intake manifold of an internal combustion engine. The inlet port in operation may be at atmospheric pressure while outlet port 112 may be at the engine intake manifold pressure (e.g., vacuum). That is, at a pressure less than atmospheric pressure.
[0013] The inventor of the present invention has innovatively recognized that lowering the mass of the moving member of the valve may substantially decrease acoustic energy generated by the valve, i.e., noise. The exemplary embodiment illustrated in FIG. 2 comprises a valve wherein reed 114 comprises a generally flexible, resilient ferromagnetic member, such as may be made up of magnetic stainless steel or other such materials. In one exemplary embodiment, the body of the valve comprises a unibody construction that may be made of plastic or any other suitable polymer material using standard molding or injection techniques. To simplify the manufacturing process, the reed may be insert molded into the body of the valve. As can be appreciated in FIG. 2, the reed 102 may include a step-wise structure 105 that allows for even a more secure mechanical connection of the reed relative to the body of the valve. The step-wise structure also provides an advantage from an electromagnetic point of view being that such step-wise structure effectively decreases the air gap g 1 between the reed and the armature and consequently the sensitivity of the reed to the electromagnetic actuator is enhanced. The solenoid actuator 104 may be externally affixed to the body of the valve using standard techniques for affixing a solenoid relative to a plastic body.
[0014] In another exemplary embodiment, the body of the valve may be produced using Zinc-casting techniques, such as may be commercially available from Fishercast Div. Of Fisher Gauge Limited, Canada, or injection molding of thixotropic semi-solid alloy available from Thixomat of Ann Arbor, Mich., USA. As will be appreciated by those skilled in the art, insert molding or insert casting can be highly efficient techniques as compared to more traditional techniques for constructing the valve that rely on the assembly of discrete parts, such as through soldering, connectors, fasteners, adhesives, etc. The benefits of insert molding/casting over such traditional techniques may include at least the following: reduced assembly and labor cost, reduced size and weight, increased reliability and increased design flexibility. For readers desirous of background information regarding Zinc Casting, see, for example, article titled “Revolution in Zinc Casting” by William Mihaichuk, as reprinted from “Machine Design” Dec. 8, 1988, which article is herein incorporated by reference. As will be appreciated by those skilled in the art, a valve having a metal body would be particularly useful for applications that require stricter control of fuel vapor diffusion through the walls of the valve since a metal valve would have reduced permeability relative to the fuel vapors passing through the valve, as compared to a plastic valve. The use of the expression Zinc Casting is meant to use terminology well-understood in the art of casting and is not meant to limit the invention to the use of zinc material since other metals, such as aluminum, magnesium and alloys, such as Zinc/aluminum and Zamak alloys could be employed in lieu of zinc.
[0015] In one exemplary embodiment in order to keep the length of the air gap g between the tip of the reed and the armature relatively small, it may be desirable to configure the cross section of the canister port rectangular in lieu of circular so that the air gap g corresponds to the smaller dimension of the rectangular cross section. In essence, the aspect ratio of the rectangular cross section would be selected to meet the volumetric flow requirements of the valve while ensuring that the air gap is sufficiently small so that no excessive electromagnetic energy is required to actuate the reed. It will be appreciated that the present invention is not limited to circular or rectangular cross-sections since other configurations, such as elliptical could be used.
[0016] [0016]FIG. 3 is a cross-sectional view of another exemplary embodiment of a unibody purge valve 200 embodying aspects of the present invention. As shown in FIG. 2, valve 200 includes a normally closed diaphragm 202 that may deflect to an open condition, represented by diaphragm position 203 , in response to an appropriate voltage signal connected to an associated electromagnetic diaphragm actuator 204 , such as may be made up of an armature 206 and a winding 208 . Purge valve 200 , in response to the voltage signal applied to actuator 204 , allows to selectively communicate the inlet port 110 with the outlet port 112 through an opening 214 .
[0017] Diaphragm 202 comprises a generally flexible, resilient ferromagnetic member, such as may be made up of magnetic stainless steel or other such materials. As shown in FIG. 3, the diaphragm may be configured to provide a circumferentially-extending spring structure 210 that normally urges the diaphragm against the opening 214 , and, in response to the actuating force from the actuator 204 , allows the diaphragm to extend to the open condition. As described in the context of FIG. 2, the body of the valve may comprise a unibody construction that may be made of plastic or any other suitable polymer material using standard molding or injection techniques. In this embodiment, the diaphragm may be insert molded into the body of the valve. The diaphragm may include a plurality of anchor holes that would allow the molding or casting material to form an even stronger insert connection.
[0018] While the preferred embodiments of the present invention have been shown and described herein, it will be obvious that such embodiments are provided by way of example only. Numerous variations, changes and substitutions will occur to those of skill in the art without departing from the invention herein. Accordingly, it is intended that the invention be limited only by the spirit and scope of the appended claims. | A valve and method of constructing same for a purge control device are provided. The valve includes an integral body. The valve further includes a resilient member inserted into the integral body. The resilient member is electromagnetically responsive so that the member can be selectively actuated between respective open and close conditions. An electromagnetic actuator is affixed to the integral body to generate an electromagnetic field for selectively actuating the resilient member between the open and closed conditions. The mass of the resilient member is sufficiently low so that the level of noise produced by the valve is correspondingly low. | 5 |
REFERENCE TO RELATED APPLICATIONS
This application is a continuation of PCT/DE03/02639 filed Aug. 6, 2003, which was not published in English, which claims the benefit of the priority date of German Patent Application No. DE 102 39 855.0, filed on Aug. 29, 2002, the contents of which both are herein incorporated by reference in their entireties.
FIELD OF THE INVENTION
The present invention relates to a circuit arrangement with a radio-frequency mixer and to a receiver arrangement with the circuit arrangement.
BACKGROUND OF THE INVENTION
Particularly in mobile radio, there is the trend toward “multiband” receivers, which are designed to receive radio signals on different frequency bands. In Germany, for example, there are two different frequency bands for the GSM (Global System for Mobile communication) mobile radio standard, namely 900 MHz and 1 800 MHz. While the “D networks” operate in the frequency range around 900 MHz, the “E networks” have an associated frequency range around 1 800 MHz. Mobile radios which can send and receive on both frequency levels are called dual-band appliances.
In order to allow mobile radios to be used worldwide within the context of the globalization of the markets and the high level of user mobility, it is desirable for just one appliance to be provided with access not just to the frequency ranges around 900 and 1 800 MHz but also to other frequency ranges, such as GSM 1 900 and GSM 800, as are used in the USA, for example.
In the reception signal paths of such mobile radio receivers, there is now the problem of designing channel filters, amplifiers etc. to be suitable for these various frequency bands. Multiband receivers are normally designed such that a separate reception path is provided for each reception band. This reception path comprises not only a channel filter but also a specially adapted low noise preamplifier, and also a separate down-conversion frequency mixer.
The documents WO 02/27953, U.S. Pat. No. 6,029,052 and U.S. Pat. No. 6,405,025 each describe different embodiments of receivers. Each receiver contains a plurality of parallel receiver paths with a respective low noise amplifier. The outputs of the amplifiers, which are isolated from one another, are coupled to a jointly used radio-frequency mixer. Each amplifier is designed to amplify a signal predetermined by a mobile radio standard.
A drawback of such a receiver architecture is the relatively high component complexity and the associated area involvement for integrating such circuits.
SUMMARY OF THE INVENTION
The present invention includes a circuit arrangement with a radio-frequency mixer and also a receiver arrangement that includes this circuit arrangement. The circuit arrangement and the receiver can be integrated on a smaller area and nevertheless has good radio-frequency properties.
In accordance with an aspect of the present invention, a circuit arrangement with a radio-frequency mixer is provided. The circuit arrangement, having:
the radio-frequency mixer with a first input, with a second input and with an output, a first preamplifier with an input and with an output, which is coupled to the first input of the radio-frequency mixer, a means for turning on and off the first preamplifier, which means is coupled to the first preamplifier, a second preamplifier with an output, which is connected to the output of the first preamplifier to form a common output node, and a means for turning on and off the second preamplifier, which means is coupled to the second preamplifier.
In line with the present principle, a common radio-frequency mixer can be used which is actuated by different reception paths designed for various frequency bands. This can reduce the chip area requirement of a multiband receiver based on a circuit arrangement of this type. The preamplifiers in the present circuit arrangement have a common output which is coupled to the common radio-frequency mixer.
It is in line with the present principle for it to be possible to dispense with providing multiband receivers with a separate radio-frequency mixer for each reception path for the purpose of useful signal processing.
The common output node of the preamplifiers is coupled to the radio-frequency mixer, such as via a coupling capacitance.
The common output node and the common radio-frequency mixer also significantly reduce the capacitive load on the respective preamplifier which is turned on, which improves the radio-frequency characteristics.
The means for turning on and off the preamplifiers advantageously allow these preamplifiers to be turned on and off independently of one another and according to the desired reception band.
The input transistors in the preamplifiers can each be connected up as diodes which can be turned on and off.
The preamplifiers can have not only a common output node but also a common electrical load, which may be in the form of a current source connected to supply potential.
In another aspect of the invention, the first and second preamplifiers may have been adapted to suit the special requirements of the respective frequency band for which they are intended to be used.
The radio-frequency mixer is optionally in the form of a broadband mixer.
The preamplifiers are can be in the form of low noise preamplifiers, referred to as LNAs (Low Noise Amplifier).
It is naturally within the scope of the invention for the present principle to be applied to arrangements containing three or more preamplifiers. In this case, all of the preamplifiers have a common output node. Typically, each preamplifier is associated with one frequency band and/or with one modulation method.
In accordance with another aspect of the present invention, a receiver arrangement comprising the circuit arrangement of above is disclosed and comprises:
a means for inputting a radio-frequency signal, a first reception path having a first bandpass filter with an input, which is coupled to the means for inputting a radio-frequency signal, and with an output and also having the first preamplifier, whose input is coupled to the output of the first bandpass filter, and a second reception path having a second bandpass filter with an input, which is coupled to the means for inputting a radio-frequency signal, and with an output and also having the second preamplifier, whose input is coupled to the output of the second bandpass filter.
In line with the proposed principle, a dual-band receiver or multiband receiver contains two reception paths whose inputs can be coupled to a common antenna or to a respective associated, separate antenna. Instead of the antenna, it is also possible to provide another means for inputting a radio-frequency signal.
The reception paths each have a preamplifier, and the two preamplifiers have a common output node. The common output node is again coupled to a common down-conversion frequency mixer.
In addition to the advantages which have already been explained, implementing the circuit arrangement with a radio-frequency mixer based on the present principle in a receiver arrangement has the advantage that the two reception paths can be adapted, for example in terms of the bandpass filters, to suit the respective associated frequency band exactly and with a high level of selectivity.
Similarly, the preamplifiers which are connected downstream of the bandpass filters may also be adapted to suit the respective associated reception band and may accordingly be in different forms. Despite this advantageous adaptability of the components which are crucial for channel selection, the present principle can nevertheless be used to save a significant amount of chip area by virtue of a common down-conversion frequency mixer being used.
Since further coupling capacitances associated with each preamplifier can be dispensed with in the case of the described, preferred coupling of the common output node to the mixer input via a coupling capacitance, an additional improvement in the radio-frequency characteristics of the dual-band receiver is obtained.
In line with another aspect, a control device is provided which can use the means for turning on and off the preamplifiers to connect and disconnect said preamplifiers independently of one another. Of the plurality of preamplifiers, no more than one is on at the same time. This achieves a further noise improvement, and also reduces the power consumption of the receiver as a whole.
It is within the scope of the invention for both the circuit arrangement with a radio-frequency mixer and the receiver arrangement with the circuit arrangement to be developed by providing third, fourth or even more preamplifiers which are each designed to be able to be connected and disconnected independently of one another. This allows the dual-band receiver to be easily developed as a triband receiver or generally as a multiband receiver.
Further details and refinements of the present invention are disclosed.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention is explained in more detail below using a plurality of exemplary embodiments with reference to drawings, in which:
FIG. 1 shows an exemplary embodiment of a circuit arrangement with a radio-frequency mixer based on the present principle, to which three preamplifiers are connected at the input.
FIG. 2 shows an exemplary dual-band receiver with the connection of preamplifiers and radio-frequency mixers in two reception paths.
DETAILED DESCRIPTION OF THE INVENTION
The present invention will now be described with reference to the drawings wherein like reference numerals are used to refer to like elements throughout. The illustrations and following descriptions are exemplary in nature, and not limiting. Thus, it will be appreciated that variants of the illustrated systems and methods and other such implementations apart from those illustrated herein are deemed as falling within the scope of the present invention and the appended claims.
FIG. 1 shows three preamplifiers 1 to 3 with a common output node 6 to which a common, broadband radio-frequency mixer 4 is connected.
The first, second and third preamplifiers 1 to 3 are in the form of low noise preamplifiers (LNA) and are each designed using balanced circuitry. Each preamplifier 1 to 3 comprises two emitter-coupled NPN bipolar transistors 11 , 12 ; 21 , 22 ; 31 , 32 . The common emitter node of the amplifier transistors 11 , 12 ; 21 , 22 ; 31 , 32 connected to one another in pairs is connected to a common reference potential connection 5 via a respective resistor 13 , 23 , 33 . Each preamplifier 1 , 2 , 3 has a separate radio-frequency input 14 , 24 , 34 , with two respective input terminals, a respective one of which is connected to a respective associated base connection of an amplifier transistor 11 , 12 ; 21 , 22 ; 31 , 32 . The radio-frequency inputs 14 , 24 , 34 can be supplied with a respective differential signal RF 1 , RF 1 X; RF 2 , RF 2 X; RFn, RFnX. These inputs 14 , 24 , 34 can have respective reception signal paths of a radio receiver connected to them, which are designed for different frequency bands or modulation methods. The collector connections of the transistors 11 , 12 ; 21 , 22 ; 31 , 32 are connected to one another in respective pairs at a common output node 6 , that is to say that the collector connections of the transistors 11 , 21 , 31 are connected to one another at one node and the collector connections of the transistors 12 , 22 , 32 are connected to one another at a further circuit node which, together with the first node, forms the balanced output node 6 of the preamplifiers 1 to 3 .
In order to turn on and off the preamplifiers 1 to 3 independently of one another, a respective path is provided between the base connection and the collector connection of the transistors 11 , 12 ; 21 , 22 ; 31 , 32 , which path respectively comprises a series circuit comprising a resistor 15 , 16 , 25 , 26 , 35 , 36 and a switch 17 , 18 , 27 , 28 , 37 , 38 . The two switches 17 , 18 ; 27 , 28 ; 37 , 38 associated with a preamplifier 1 , 2 , 3 are turned on and off together in respective pairs. When the switches are in the open state, the respectively associated preamplifier 1 , 2 , 3 is off. In order to turn on one of the preamplifiers 1 to 3 , the switch pair 17 , 18 ; 27 , 28 ; 37 , 38 associated with it is closed. The two other switch pairs remain open. The balanced output node 6 , which is common to all of the preamplifiers 1 to 3 , is connected to a supply potential connection 7 via a respective current source 61 , 62 which is common to all of the preamplifiers.
In addition, the balanced output 6 is connected to the first input 43 of the radio-frequency mixer 4 , which input is designed for differential signal transmission, via a respective series capacitor 41 , 42 . A second input 44 of the radio-frequency mixer 4 is designed to supply a local oscillator signal containing signal components which have been phase-shifted through 90° with respect to one another. At the output of the mixer 4 , which is provided with reference symbol 45 and is likewise of balanced design, it is possible to tap off a baseband signal BB or an intermediate-frequency signal, depending on the architecture of the receiver.
In the present circuit arrangement, the preamplifiers 1 to 3 , which are each associated with different reception paths, have a common output 6 which is connected to the associated mixer 4 . There are thus advantageously just two coupling capacitances 41 , 42 per mixer input 43 . This in turn means that there is a particularly small capacitive load at the output of the respective active low noise preamplifier 1 to 3 . The circuit therefore has improved radio-frequency characteristics.
To be able to turn on and off the preamplifiers 1 to 3 independently of one another, the input transistors 11 , 12 , 21 , 22 , 31 , 32 are connected up as switchable diodes.
The circuit arrangement from FIG. 1 may advantageously be used in a triband receiver, for example. A triband receiver of this type may be used to process the mobile radio standards GSM 900, GSM 1 800 and GSM 1 900, for example or other frequency ranges.
The principle described may naturally also be applied when there are just two preamplifiers or may alternately be extended to any number of preamplifiers and reception paths.
In alternative embodiments, it is also possible for current sources to be provided instead of the resistors 13 , 23 , 33 .
Instead of the current sources 61 , 62 , any other, even complex, electrical loads may be provided in alternative embodiments.
Between the collector connections of the differential amplifier transistors and the common output node 6 there may be a respective cascade transistor. This achieves a further increase in insulation.
In alternative embodiments, an additional amplifier stage may be added between the low noise preamplifiers 1 , 2 , 3 and the mixer 4 .
FIG. 2 shows, by way of example, the application of the principle from FIG. 1 in a dual-band receiver with two reception paths RX 1 , RX 2 . In that case, an antenna 81 has a coupling element 82 connected to it, with a first output, which is connected to a first surface acoustic wave filter 83 , and a second output, which is connected to a second surface acoustic wave filter 84 . The surface acoustic wave filters 83 , 84 are used to select the respective frequency band associated with the reception path RX 1 , RX 2 and to suppress unwanted frequency components. At the outputs of the filters 83 , 84 , there is a respective preamplifier 1 , 2 , such as the preamplifiers shown and connected to one another in FIG. 1 . If the preamplifiers of FIG. 1 are employed, the switches 17 , 18 ; 27 , 28 1 , 2 have their control inputs connected to an actuation circuit 9 , which activates the respective desired preamplifier. The outputs of the preamplifiers 1 , 2 are connected via coupling capacitances 41 , 42 to a first input of the radio-frequency mixer 4 , which is in the form of a down-conversion mixer. The second input 44 is used to supply a local oscillator signal LO. At the output 45 , it is possible to tap off a baseband signal BB.
The preamplifiers 1 , 2 can employ different frequency ranges and/or modulation methods. For example, the preamplifiers 1 , 2 can employ frequency ranges such as, about 800 to 900 MHz, about 880 to 960 Mhz, about 1700 to 1900 Mhz, about 1850 to 2000 Mhz, and the like. As another example, the preamplifiers 1 , 2 can employ frequency ranges for different communication standards such as GSM 900, GSM 1800, GSM 1900, GSM 800, and the like. It is noted that the present invention is not limited to a specific group or range of frequencies.
The chip area saving which is possible with the present principle is clear to see. In the illustration in FIG. 2 , just one common down-conversion frequency mixer 4 is required, despite the option of being able to process various frequency bands. The common output node 6 of the preamplifiers 1 , 2 means that the capacitive load governed by the coupling capacitances 41 , 42 is also relatively small.
It goes without saying that it is within the scope of the invention to apply the principle shown also to receivers with more than two frequency bands, for example to triband receivers.
Instead of the circuit implementation shown in FIG. 1 using differential, bipolar circuitry, it is also possible to implement it using “single-ended circuitry” and/or using CMOS circuitry within the scope of the invention.
Although the invention has been illustrated and described above with respect to a certain aspects and implementations, it will be appreciated that equivalent alterations and modifications will occur to others skilled in the art upon the reading and understanding of this specification and the annexed drawings. In particular regard to the various functions performed by the above described components (assemblies, devices, circuits, systems, etc.), the terms (including a reference to a “means”) used to describe such components are intended to correspond, unless otherwise indicated, to any component which performs the specified function of the described component (i.e., that is functionally equivalent), even though not structurally equivalent to the disclosed structure, which performs the function in the herein illustrated exemplary implementations of the invention. In this regard, it will also be recognized that the invention may include a computer-readable medium having computer-executable instructions for performing the steps of the various methods of the invention. In addition, while a particular feature of the invention may have been disclosed with respect to only one of several implementations, such feature may be combined with one or more other features of the other implementations as may be desired and advantageous for any given or particular application. Furthermore, to the extent that the terms “includes”, “including”, “has”, “having”, “with” and variants thereof are used in either the detailed description or the claims, these terms are intended to be inclusive in a manner similar to the term “comprising”. Also, the term “exemplary” as utilized herein simply means example, rather than finest performer.
LIST OF REFERENCE SYMBOLS
1 Preamplifier
2 Preamplifier
3 Preamplifier
4 Mixer
5 Reference potential connection
6 Output node
7 Supply potential connection
9 Control circuit
11 Transistor
12 Transistor
13 Resistor
14 Input
15 Resistor
16 Resistor
17 Switch
18 Switch
21 Transistor
22 Transistor
23 Resistor
24 Input
25 Resistor
26 Resistor
27 Switch
28 Switch
31 Transistor
32 Transistor
33 Resistor
34 Input
35 Resistor
36 Resistor
37 Switch
38 Switch
41 Capacitance
42 Capacitance
43 Input
44 Input
45 Output
61 Current source
62 Current source
81 Antenna
82 Coupling element
83 Bandpass filter
84 Bandpass filter
BB Baseband
LO Local oscillator signal
RX 1 Reception path
RX 2 Reception path
RF 1 Radio-frequency signal
RF 1 X Radio-frequency signal
RF 2 Radio-frequency signal
RF 2 X Radio-frequency signal
RFn Radio-frequency signal
RFnX Radio-frequency signal | The invention specifies a circuit arrangement with a radio-frequency mixer ( 4 ) in which a plurality of preamplifiers ( 1, 2, 3 ) in a receiver have a common output node ( 6 ). This node is connected to a common, broadband radio-frequency mixer ( 4 ) via common coupling capacitances ( 41, 42 ). Switching means ( 17, 18; 27, 28; 37, 38 ) can be used to connect and disconnect the preamplifiers ( 1 to 3 ), which can be associated with various frequency bands, independently of one another. The present principle can be applied in multiband receivers in mobile radio and allows integration using little chip area with good radio-frequency characteristics. | 7 |
TECHNICAL FIELD
This document relates to a drive head for a wellhead.
BACKGROUND
Stuffing boxes are used in the oilfield to form a seal between the wellhead and a well tubular passing through the wellhead, in order to prevent leakage of wellbore fluids between the wellhead and the piping. Stuffing boxes may be used in a variety of applications, for example production with pump-jacks, and inserting or removing coiled tubing. Stuffing boxes may incorporate a tubular shaft mounted for rotation in the housing for forming a stationary seal with the piping in order to rotate with the piping. The tubular shaft in turn dynamically seals with the stuffing box housing. Designs of this type of stuffing box can be seen in the following patents: U.S. Pat. No. 7,044,217 and CA 2,350,047. In other designs, the stuffing box may instead form a dynamic seal directly against the piping without incorporating a rotating tubular shaft. Stuffing boxes may be used for rotating or reciprocating pumps.
Drive heads are used in tandem with stuffing boxes. In some cases the drive head sits above the stuffing box. In other cases the stuffing box is incorporated into the drive head or sits above the drive head, for example in FIG. 3 of U.S. Pat. No. 7,044,217.
Leakage of crude oil from a stuffing box is common in some applications, due to a variety of reasons including abrasive particles present in crude oil and poor alignment between the wellhead and stuffing box. Leakage costs oil companies money in service time, down-time and environmental clean-up. Leakage is especially a problem in heavy crude oil wells in which oil may be produced from semi-consolidated sand formations where loose sand is readily transported to the stuffing box by the viscosity of the crude oil. Costs associated with stuffing box failures are some of the highest maintenance costs on many wells.
SUMMARY
A drive head for a wellhead is disclosed, the drive head comprising: a rod drive; a pressure chamber; and a rod receiving part connected to the rod drive and enclosed within the pressure chamber.
A method is disclosed comprising: pressurizing a chamber mounted to a wellhead, in which the chamber encloses an upper end of a rod extending from the wellhead; and driving the rod using a rod receiving part enclosed within the chamber.
A drive head for a wellhead is disclosed, the drive head comprising: a stationary housing with a base, one or more sidewalk, and a top wall; and a rod drive connected to the stationary housing; the stationary housing defining a pressure chamber extending from an opening in the base to the top wall, in which the pressure chamber forms a dead end for a rod.
In various embodiments, there may be included any one or more of the following features: The rod drive is mounted within the pressure chamber. The rod drive is a hydraulic motor. The pressure chamber forms a casing for the hydraulic motor. A case drain is connected between the casing and a hydraulic fluid return line, which is also connected to the hydraulic motor. A rod is connected to the rod receiving part, the rod having an upper end enclosed within the pressure chamber. The pressure chamber is pressurized above a wellhead pressure. The pressure chamber is above 10 psi. The pressure chamber is above 100 psi. At least part of a top wall of the pressure vessel is removable. The rod receiving part further comprises a tubular shaft mounted for rotation, the tubular shaft having a threaded rod end coupler. The drive head is adapted for production of wellbore fluids. The drive head is adapted for a progressing cavity pump application. The rod is connected to a downhole pump. Downhole fluids are produced from the wellhead.
These and other aspects of the device and method are set out in the claims, which are incorporated here by reference.
BRIEF DESCRIPTION OF THE FIGURES
Embodiments will now be described with reference to the figures, in which like reference characters denote like elements, by way of example, and in which:
FIG. 1A is a view of a progressing cavity pump oil well installation in an earth formation for production with a typical drive head, wellhead frame and stuffing box;
FIG. 1B is a view similar to the upper end of FIG. 1 but illustrating a conventional drive head with an integrated stuffing box extending from the bottom end of the drive head;
FIG. 2 is a side elevation section view of a drive head for a wellhead;
FIG. 3 is a side elevation view of the drive head of FIG. 2 ;
FIG. 4 is a perspective view of the drive head of FIG. 2 ; and
FIG. 5 is a hydraulic fluid schematic for operating the drive head of FIG. 2 .
FIG. 6 is a side elevation view of a drive head incorporating an electric rod drive.
DETAILED DESCRIPTION
Immaterial modifications may be made to the embodiments described here without departing from what is covered by the claims.
FIG. 1A illustrates a known progressing cavity pump installation 10 . The installation 10 includes a typical progressing cavity pump drive head 12 , a wellhead frame 14 , a stuffing box 16 , an electric motor 18 , and a belt and sheave drive system 20 , all mounted on a flow tee 22 . The flow tee is shown with a blowout preventer 24 which is, in turn, mounted on a wellhead 25 . The drive head 12 supports and drives a drive shaft 26 , generally known as a “polished rod”. The polished rod is supported and rotated by means of a polish rod clamp 28 , which engages an output shaft 30 of the drive head by means of milled slots (not shown) in both parts. The clamp 28 may prevent the polished rod from falling through the drive head and stuffing box, and may allow the drive head to support the axial weight of the polished rod. Wellhead frame 14 may be open sided in order to expose polished rod 26 to allow a service crew to install a safety clamp on the polished rod and then perform maintenance work on stuffing box 16 . Polished rod 26 rotationally drives a drive string 32 , sometimes referred to as a sucker rod, which, in turn, drives a progressing cavity pump 34 located at the bottom of the installation to produce well fluids to the surface through the wellhead.
FIG. 1B illustrates a typical progressing cavity pump drive head 36 with an integral stuffing box 38 mounted on the bottom of the drive head and corresponding to the portion of the installation in FIG. 1A that is above the dotted and dashed line 40 . An advantage of this type of drive head is that, since the main drive head shaft is already supported with hearings, stuffing box seals can be placed around the main shaft, thus improving alignment and eliminating contact between the stuffing box rotary seals and the polished rod. This style of drive head may also reduce the height of the installation because there is no wellhead frame, and also may reduce cost because there are fewer parts since the stuffing box is integrated with the drive head. A disadvantage is that the drive head must be removed to do maintenance work on the stuffing box. In addition, a stuffing box is still required above the drive head 36 to dynamically seal off the rod 30 from the ambient environment. Surface drive heads for progressing cavity pumps require a stuffing box to seal crude oil from leaking onto the ground where the polished rod passes from the crude oil passage in the wellhead to the drive head.
Referring to FIG. 2 , a drive head 50 is illustrated having a rod drive 52 , a pressure chamber 54 , and a rod receiving part 56 . Rod receiving part 56 is connected to the rod drive 52 and enclosed within the pressure chamber 54 . A rod 58 may be connected to the rod receiving part 56 . In use an upper end 60 of the rod 58 is enclosed within the pressure chamber 54 . Thus, the pressure chamber 54 forms a dead end for rod 58 . Because part 56 and upper end 60 are enclosed within the pressure chamber 54 during use, there is no need for a dynamic seal, such as provided by a stuffing box, between the rod 58 and the outer ambient environment 66 .
The lack of a dynamic seal between the outer ambient environment 66 and the pressure chamber 54 is advantageous because it allows pressure chamber 54 to be pressurized to a much greater extent than if chamber 54 terminated in a dynamic seal to the ambient environment 66 as is the case when a regular stuffing box is used. This is because static seals can be pressurized to a greater extent without leaking than dynamic seals. In fact, pressure chamber 54 may be pressurized above standard case pressures, for example if chamber 54 is pressurized to above 10 psi, above 100 psi, or even as high as above 500 psi in some cases. The pressure of chamber 54 may be equal or lower than pressure line 120 (FIG. 5 ) pressure if a hydraulic motor 53 is used, described further below. The relatively high pressure of chamber 54 works against wellhead fluid pressure and across the one or more seals 62 between the chamber 54 and the well 64 , reducing the amount of wellhead fluids that undesirably cross seals 62 and enter the chamber 54 . Chamber 54 may be pressurized above a wellhead pressure. By contrast with dynamic seals of a traditional stuffing box open to atmosphere 66 , if bottom seal 59 of drive head 50 fails, pressurized fluid leaks into the well 64 and not into the atmosphere 66 .
Referring to FIGS. 2, 3, and 4 , chamber 54 may be defined by a stationary housing 68 made up of one or more sidewalk 70 , a top wall 72 , and a base 74 . Sidewall 70 is illustrated as being cylindrical, although other shapes may be used for sidewall 70 . Top wall 72 may include an annular top cap 78 connected, for example threaded, to a top hat 80 for enclosing the upper end 60 of the rod 58 ( FIG. 2 ). At least part of top wall 72 may be removable, for example to allow a convenient method of servicing components within the chamber 54 . In other cases an interior 82 of chamber 54 is accessible via suitable means, such as a window in sidewall 70 . Chamber 54 may include one or more lifting lugs 76 for transporting the drive head 50 . Base 74 may house one or more seals 62 for sealing against rod 58 in use. Base 74 may connect to wellhead 64 directly or indirectly as shown, for example through a bottom spool 84 . In other cases drive head 50 may be mounted upon a flow tee (not shown). Chamber 54 may extend from an opening 81 in the base 74 to the top wall 72 .
The pressurization advantages of chamber 54 are still realized if a stuffing box is used below chamber 54 . Bottom spool 84 is a form of stuffing box, although bottom spool 84 does not seal between wellhead fluid and outer ambient environment 66 like a normal stuffing box does. Thus, there is no dynamic seal on spool 84 between environment 66 and wellhead fluid. Bottom spool 84 may include one or more mechanisms for axially compressing seals 62 . For example, a biasing device such as spring 86 may be positioned between seals 62 and a ring 87 positioned between spool 84 and base 74 . Compression of spring 86 caused by bringing base 74 and spool 84 closer together increases sealing by seals 62 against rod 58 . In other cases one or more bolts 88 may be mounted in spool 84 to provide lateral force into a wedge piston 90 whose tapered lateral end 92 contacts a wedge ring 93 that transfers lateral force into axial compression against seals 62 . Seals 62 positioned below bottom seals 59 of base 74 are advantageously used with drive head 50 in that they allow servicing of the drive head 50 without allowing leakage of well fluids. To service drive head 50 , a user may remove top hat 80 , coupler 96 , and top wall 72 in some cases, and remove a part or all of motor 53 . Poly seals 51 prevent excess production fluids from leaking past and contaminating the pressurized chamber 54 .
The rod receiving part 56 may comprise a tubular shaft 94 or rotating sleeve mounted for rotation. The tubular shaft 94 may have a threaded rod end coupler 96 , such as a hex driver with a PR thread as shown. One or more bearings or bushings (not shown) may be used to align the shaft 94 and facilitate smooth rotation. Shaft 94 may be connected to be driven by rod drive 52 by a suitable mechanism such as meshing with a lateral extension 100 of shaft 94 . Other mechanisms of torque transfer between rod drive 52 and rod 58 may be used.
The rod drive 52 may be connected to the chamber 54 , for example mounted within the pressure chamber 54 as shown. The rod drive 52 may be a suitable motor, such as a hydraulic motor 53 . The pressure vessel 54 may form a casing 55 for the hydraulic motor 53 . A case drain 98 may be connected to the casing 55 . Hydraulic pressure and return lines may connect to a pressure line input 102 and a return line input 104 formed in housing 68 ( FIGS. 3 and 4 ). A relief valve 106 may be located on case drain 98 ( FIGS. 2-4 ). One or more fluid channels 111 may extend laterally from for example above top seal 57 of base 74 , in order to provide a leak path to allow fluid leaking from hydraulic motor 53 to preferentially collect in casing 55 . Fluid channel 111 also prevents crude oil from wellhead 64 from being forced into hydraulic motor 53 , where such oil may over pressure and damage motor 53 . Case drain 98 pressure may be set at a higher pressure than production fluid, so if hydraulic fluid is lost it goes downhole. If enough hydraulic fluid is lost, motor 53 will shut down.
Referring to FIGS. 2, 3, and 5 , a method of operation of hydraulic motor 53 will be described. Fluid from one or more hydraulic tanks 108 is pumped via pump 110 through a pressure line 112 ( FIG. 5 ). A return tank 109 may also be connected to pump 110 . A retarder 114 with a restriction 116 on bypass loop 117 may be located on line 112 to prevent or reduce backspin upon pump shut off. On pump shut off, the backspin generated by rod 58 and exerted upon motor 53 causes reverse flow of hydraulic fluid in line 112 , which cannot pass through check valve 118 , and instead flows through restriction 116 at a reduced flow rate, if at all. Restriction 116 acts as a break on backspin, and prevents the rod from damaging itself via unconstrained freewheeling. Restriction 116 also prevents or reduces the chance that hydraulic fluid contaminated with wellhead fluid is sent back to pump 110 or tank 108 .
Pressure line 112 ( FIG. 5 ) sends hydraulic fluid to motor 53 through pressure input 102 ( FIG. 3 ), where the pressure of the hydraulic fluid is used to perform work by rotating rod 58 ( FIG. 2 ). Rod 58 may connect to a downhole pump 34 for producing well fluids. Chamber 54 is pressurized by the motor case drain 98 , which is choked off via relief valve 106 . Once the work is accomplished by a given unit of fluid volume, the unit of fluid volume returns through return input 104 ( FIG. 3 ) and into return line 120 ( FIG. 5 ). Return line 120 cleans contaminants such as sand particles from return fluid by passing return fluid through a filter 122 , a check valve 124 . After filtration, the return fluid is deposited for re-use or further cleaning in a tank 126 , which may be the same as one of tanks 108 or 109 ( FIG. 5 ). If filter 122 becomes clogged, or in other events where fluid pressure in line 120 climbs beyond a predetermined level, a bypass valve 128 controlled by pressure from line 127 of line 120 bypasses return fluid past the filter 122 and into tank 126 .
Motor 53 also includes case drain 98 between the casing 55 ( FIG. 2 ) and hydraulic fluid return line 120 ( FIG. 5 ). The case drain line 98 has a line 123 that passes into a valve 130 that feeds case fluid back into return line 120 for recycling and re-use during normal pump 110 operation. Valve 130 is controlled by pressure from line 131 sent from pressure line 112 , so that the system operates as shown when pump 110 is not operating. Thus, free flow across valve 130 is allowed until the pressure line 112 pressure builds to a sufficient level to close valve 130 . When the pump 110 is shut off or pressure in line 112 reduces below a predetermined pressure, valve 130 opens to allow fluid connection between case drain 98 and return line 120 to reduce case pressure. Thus, during operation, the pressure in chamber 54 is allowed to grow to a predetermined pressure. In the event that valve 130 malfunctions and doesn't open, or another event causes an undesirable pressure increase in line 98 indicating a pressure state in pressure chamber 54 above a predetermined pressure, pressure from line 98 causes relief valve 106 to open, allowing case drain pressure to pass through bypass line 121 of line 98 and into return line 120 through check valve 132 . Running the case drain 98 to the return line 120 eliminates the need for an additional hose that would otherwise be used to keep the casing 55 at a low enough pressure to prevent dynamic seal leakage.
Drive head 50 may be used for production of wellbore fluids, such as production in a progressing cavity pumping application as shown. Drive head 50 may be adapted to be retrofitted into a wellhead 39 . In other cases drive head 50 may be adapted for an integral application, for example in the style shown in FIG. 1B . Connections between components may be accomplished by suitable mechanisms such as bolting, threading, clamping, and retaining. Although described above for a rotating rod embodiment, drive head 52 may be used in a reciprocating rod application as well.
It should be understood that various other components may be incorporated into drive head 50 . For example, various seals 89 may be provided at points between rod 58 and housing 68 , or between other components. Similarly, o-rings, gaskets, packing and other components may be used.
Referring to FIG. 2 , the one or more seals 62 may comprise packing 63 , packing 67 , or other suitable seals such as lip seals 65 or poly seals 51 . Seals 62 may be mechanical or non-mechanical seals. Different packing may be used for packing 63 and 67 . One or more rings such as brass rings may be located on either side of seals 62 . O-rings 89 or other suitable gaskets may be used throughout drive head 50 . In general, where the word seal is mentioned in this document, one or more seals may be provided to effectively operate as a single seal, for example observed in the stacking of packing seals 65 .
It should be understood that various other components such as blow out preventers may be provided with the drive head 50 for wellhead applications to be carried out. Drive head 50 may incorporate a lubrication system (not shown) for lubricating various components, such as the one or more seals 62 . Various components discussed herein may include sub-components, such as the plural sleeves that thread together to make up the top wall 72 of FIG. 2 . As well, components that are shown as being separate may be combined integrally, for example base 74 and side wall 70 . Connections between components, or the mounting of one component to another, may be done through intermediate parts. Figures may not be drawn to scale, and may have dimensions exaggerated for the purpose of illustration. Drive head 50 may have no rotating parts or dynamic seals on the exterior of drive head 50 . Non hydraulic drives may be used, for example if an electric motor is used as shown in FIG. 6 , although a pressurization system may be required to pressurize chamber 54 .
In the claims, the word “comprising” is used in its inclusive sense and does not exclude other elements being present. The indefinite article “a” before a claim feature does not exclude more than one of the feature being present. Each one of the individual features described here may be used in one or more embodiments and is not, by virtue only of being described here, to be construed as essential to all embodiments as defined by the claims. | A drive head for a wellhead, the drive head comprising: a rod drive; a pressure chamber; and a rod receiving part connected to the rod drive and enclosed within the pressure chamber. A method comprising: pressurizing a chamber mounted to a wellhead, in which the chamber encloses an upper end of a rod extending from the wellhead; and driving the rod using a rod receiving part enclosed within the chamber. | 4 |
CROSS REFERENCE TO RELATED APPLICATION
[0001] This is a divisional of U.S. patent application Ser. No. 10/522,850, filed Jan. 28, 2005, now U.S. Pat. No. 7,226,663, issued Jun. 5, 2007, which is the § 371 U.S. National Stage application of International Application No. PCT/US2003/024070, filed Jul. 31, 2003, which was published in English under PCT Article 21(2), which in turn claims the benefit of U.S. Provisional Application No. 60/400,897, filed Aug. 1, 2002.
ACKNOWLEDGEMENT OF GOVERNMENT SUPPORT
[0002] This invention was made in part using funds provided by the National Science Foundation Grant Nos. DMR-0097575 and ECS-0217061. The United States government may have certain rights in this invention.
FIELD
[0003] This disclosure concerns a method for synthesizing nanoscale structures in defined locations, and composites and devices comprising nanoscale materials.
BACKGROUND
[0004] Since their discovery in 1991 by microscopist Sumio Iijima, carbon nanotubes have intrigued researchers with their structures and the applications enabled by their unique physical properties. Iijima, S. Nature, 1991, 354, 56. Nanotubes exhibit high chemical resistance and mechanical strength, among other desirable physical properties. Ongoing challenges to exploiting these desirable properties include difficulties associated with isolating and manipulating nanotubes for use as discrete device elements.
I. Carbon Nanotubes
[0005] Carbon nanotubes are graphene cylinders that can be capped at either end with a fullerene-like structure. When he discovered nanotubes, Iijima was analyzing materials formed at the cathode during arc discharge synthesis of fullerenes and observed a variety of related structures, including novel, closed graphitic structures, such as nanotubes and nanoparticles. Since Iijima's initial discovery, carbon nanotubes have attracted considerable interest from the scientific community, and have prompted much research into their potential applications. Research also has been directed to other nanoscale materials, including inorganic tubular materials, such as silicon carbide and tungsten sulfide nanotubes. However, the difficulties in manipulating individual nanoscale structures, such as nanotubes and connecting such structures to other materials remains a challenging obstacle to achieving practical applications of these intriguing materials.
II. Applications of Nanotubes
[0006] Generally, known methods for synthesizing nanotubes provide only unorganized, tangled nanotubes and bundles of nanotubes. These bulk materials are useful as additives for improving the material properties of polymer or metal composites. See, U.S. Pat. No. 6,280,697, issued to Zhou, et al. (Zhou). Zhou describes using bulk carbon nanotubes with intercalated lithium ions to improve the performance of lithium ion batteries. U.S. Pat. No. 6,420,293, issued to Chang, et al. (Chang), describes using nanotubes in bulk as a filler material in ceramic metal oxides to enhance the ceramic's mechanical strength. Despite promising properties and successes using nanotubes as a bulk material, the difficulties in localizing and organizing nanotubes have limited the fabrication of functional devices using nanotube components.
III. Focused Ion Beam
[0007] Focused ion beam (FIB) systems have been manufactured commercially for about fifteen years, and primarily are used for semiconductor failure analysis and device edit. FIB systems are similar to scanning electron microscopy (SEM) systems except that FIB systems use a finely focused beam of ions, such as gallium ions, instead of electrons. FIB systems can be used for microscopy, micromachining and deposition processes. More recently, dual-beam systems, including both an electron beam (EB) column and a FIB column, have been developed. EB has a smaller beam spot size than FIB, which allows the imaging of more detailed features than FIB. See High Resolution Focused Ion Beams: FIB and Its Applications; by Orloff, J., Utlaut, M., Swanson, L. Kluwer Academic/Plenum Publisher: New York, Boston, Dordrecht, London, Moscow; 2002, which is incorporated herein by reference.
SUMMARY
[0008] A method is disclosed for fabricating nanoscale materials, such as nanotubes, in defined locations. Also disclosed are electronic devices fabricated according to embodiments of the method. In one embodiment of the method, a catalytic material is directly deposited on a substrate using FIB-induced deposition. Nanoscale materials can then be synthesized only at the sites having catalyst. In another aspect of the method, a material, such as a conducting, semiconducting or insulating material, is deposited on the substrate at defined locations prior to catalyst deposition. Catalytic material can then be deposited selectively on the first deposited material, and nanoscale material can be synthesized selectively in a pattern defined by the catalyst location. FIB milling can be used in conjunction with EB-induced and/or FIB-induced deposition to refine deposited features, or can be used following non-selective deposition to provide a desired pattern.
[0009] Particular materials that can be deposited include, without limitation W, Pt, Au, Al, Fe, Ni, Co, Ti, Ta, Cu, and combinations thereof. A particularly useful metal for practicing disclosed embodiments of the present method for fabricating electronic devices is Pt. A second metal that is particularly useful for fabricating a nanotube field emitter device is W. Exemplary useful metal catalysts and catalyst precursors include Fe, Ni, Co or their combinations.
[0010] The structures synthesized can be any nanoscale structures, such as nanowires, nanotubes, nanocoils or nanobelts. The nanoscale structures typically contain a material such as zinc oxide, silicon dioxide, tungsten oxide, cadmium sulfide, carbon, silicon carbide, or a combination thereof. Nanotubes, for example, can be any type of nanoscale tubular materials, such as carbon nanotubes, silicon carbide nanotubes, tungsten sulfide nanotubes and other inorganic nanotubes. In one aspect the nanotubular structures are solid materials, for example as wires or filaments. Such solid materials, including nanowires, can be made from zinc oxide, silicon dioxide, tungsten oxide, cadmium sulfide, carbon, silicon carbide, or a combination thereof. Additionally, the nanotubes can be single-walled or multi-walled, and can be synthesized so that they are oriented in any direction. For example, one composite prepared included a substantially horizontal nanotube connecting two metal pillars. This type of composite is useful as a two terminal device. Another composite included a substantially vertical nanotube. An array containing such substantially vertical nanotubes is useful for forming a field emission device.
[0011] One aspect of the method involves synthesizing a nanotube in direct electrical contact with an electronic component. For example, nanotubes can be synthesized directly on a conducting or semiconducting electrode. Thus, an electrical connection is provided to the nanotubes without need for tedious manipulation of nanoscale components. For example, a metal pillar can function as a conductive contact and can connect the nanotube to a device or device component on a substrate. In another embodiment, a device having at least two terminals can be fabricated. Particular examples of such devices include diodes, triodes, optoelectronic devices, acoustic wave devices, electromechanical resonators, and transistors. In an embodiment of a transistor, a source can be provided by depositing a metal pillar on a substrate. A catalytic material can be deposited or patterned according to the present method, such that a nanotube can be synthesized with a first end contacting the pillar and extending substantially horizontally so that a second end contacts a second pillar. The first pillar provides a source connection and the second pillar is connected to the second end of the nanotube, thereby providing a drain connection. The transistor can be switched using a field effect gate, which also can be fabricated according to the present disclosure. Alternatively, because substantially vertical nanotubes can be prepared according to embodiments of the method, a transistor can be fabricated using a substantially vertical nanotube.
[0012] In another aspect of the method nanotube composites that function as field emitters can be prepared. Embodiments of the method are useful for preparing defined arrays of nanotube field emitters. Arrays having substantially vertically aligned nanotubes are particularly useful for preparing field emission devices suitable for use, for example, in a flat panel display. Such field emitters can be assembled by patterning pillars on a substrate and then patterning a catalytic material, so that catalytic material resides on top of the pillars. Nanotubes can then be synthesized on the pillars. Each pillar bearing a nanotube, or cluster of nanotubes, can then serve as an independent field emitter and provide a single pixel in a flat panel display. Alternatively, a single pixel can comprise a cluster of pillars bearing nanotubes. The array of individual nanotube field emitters may be formed on a substrate of any size; the upper limit of such an array is only limited by the size of the chamber used for nanotube synthesis.
[0013] Another embodiment of a nanotube field emitter device is useful as a monochromatic electron source. In this device, a nanotube serves as a high brightness field emission cathode. This device can be made by synthesizing a nanotube, such as a carbon nanotube, typically a multi-walled carbon nanotube, directly on a metal tip, examples of which include W, Pt, Au, Al, Fe, Ni, Co, Ti, Ta, Cu, alloys thereof, and combinations thereof. Such metal tips can be fabricated according to the present method by FIB-induced deposition and/or patterning the metal such that the metal tip typically has a diameter of about 1 μm or less. Tungsten is a preferred metal for fabricating high-brightness, nanotube field emitters, where the tungsten metal tip serves as a substrate hosting a carbon nanotube. This type of field emitter is useful, for example, as an electron source in a field emission microscope.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] FIG. 1 is a schematic illustrating a process for synthesizing arrays of nanotubes in defined locations.
[0015] FIG. 2A is a schematic illustrating one embodiment of a defined array of substantially vertical nanotubes.
[0016] FIG. 2B is a schematic illustrating one embodiment of substantially horizontal nanotubes synthesized in defined locations.
[0017] FIG. 2C is a schematic of a transistor formed using a nanotube.
[0018] FIG. 3 is a schematic illustrating direct deposition of catalytic material in defined locations on a substrate, followed by nanotube synthesis.
[0019] FIG. 4 is a schematic illustrating assembly of one example of a nanotube field emitter device.
[0020] FIG. 5A is a graph of current vs. voltage behavior for a nanotube field emitter fabricated according to Example 7.
[0021] FIG. 5B is a Fowler-Nordheim plot for a nanotube field emitter fabricated according to Example 7.
[0022] FIG. 6A is a digital image illustrating a 3×4 array of Pt pillars on a substrate, each pillar having an indentation formed by FIB milling of the top surface of the pillars.
[0023] FIG. 6B is a digital image illustrating a single pillar of FIG. 6A .
[0024] FIG. 7 is a digital image illustrating an array of Pt pillars of cylindrical shape formed by FIB-induced deposition.
[0025] FIG. 8 is a digital image (scale of 500 nm provided in upper left) of a bundle of nanotubes synthesized on a Pt pillar.
DETAILED DESCRIPTION
[0026] Embodiments of the present disclosure concern a method for fabricating new, composite materials by synthesizing nanotubes in defined locations, and devices made by the method. Synthesizing nanotubes in defined locations facilitates production of devices that exploit their unique properties.
[0027] Another method for synthesizing nanotubes is disclosed by U.S. Pat. No. 6,346,189, issued to Dai, et al. (Dai '189). Dai '189 discloses the synthesis of nanotubes on “catalyst islands” on a substrate. The method disclosed by Dai '189 produces catalyst islands according to a multi-step procedure that uses e-beam lithography to produce a patterned resist. A catalyst is then deposited using the patterned resist to define sites of catalyst deposition and a “lift-off” procedure is performed to remove the resist.
[0028] Another method is disclosed by U.S. Pat. No. 6,457,350 to Mitchell (Mitchell), which teaches a technique for placing a nickel catalyst on the tip of a pointed tungsten wire by directional deposition and anisotropic etching. Mitchell teaches that such structures are useful for scanning probe microscopy.
[0029] An example of a micromanipulation method is taught by Fransen et al. Appl. Surf: Sci. 1999, 146, 312-327 (Fransen). Fransen discloses a manual method using carbon glue and micromanipulators for placing a carbon nanotube on the side of a tungsten tip to make a field emission device.
[0030] In contrast, the present disclosure describes an efficient method for synthesizing nanotubes in defined locations via direct patterning and/or deposition of catalytic materials without using lithography or resist patterning and removal procedures. Moreover, embodiments of the disclosed method enable the deposition of other materials, particularly materials that are useful in forming electronic device components. For example, in one embodiment, a first material, such as a conducting or semiconducting material is deposited in defined locations, followed by the deposition of a catalytic material on the first material. Nanotubes are synthesized at the sites having catalyst, thereby forming an electrical connection suitable for fabricating a nanotube-based electronic device, such as a field emitter, diode or transistor.
[0031] In particular examples, the first deposited material discussed above is deposited to form a pillar on a substrate. “Pillar” is defined herein as any localized, deposited material. Pillars can be formed in any size, any geometric shape, and any pattern, with the lower size limit being determined by the focused beam spot size of the FIB or electron beam system. For example, material can be deposited with a lateral dimension of less than about 50 nm. The upper size limit is bounded solely by the deposition rate and commercial need. The vertical height of pillars is readily controlled as is known to those of ordinary skill in the art by controlling the rate of deposition by varying beam current, dwell time and flow of gaseous precursor with the time of deposition at a given rate determining the vertical height.
[0032] Pillars can be deposited and/or patterned to provide a defined array of pillars on the substrate. Alternatively, pillars may be formed according to an existing pattern on the substrate, such as a pattern defined by electronic circuitry formed on the substrate. Thus, a pillar can provide an electrical connection between a nanotube and an electronic device.
[0033] Catalytic materials can be deposited on a substrate having pillars by any method, and then patterned such that the catalytic material is localized on the pillars. In another aspect of the method, catalytic material is deposited directly by FIB-induced deposition. After FIB-induced deposition, the catalytic material optionally can be patterned to further define catalytic sites and define sites of nanotube synthesis. Thus, nanotubes can be synthesized in defined locations, as determined by the patterning process.
[0034] In general, the term “catalytic material” is used to refer to catalysts and catalyst precursors for nanotube synthesis.
[0035] FIG. 1 illustrates a first step in an embodiment for synthesizing a structure 10 having nanotubes in defined locations. Structure 10 includes a substrate 12 having pillars 14 deposited on the surface. Substrate 12 can be any solid material, and typical substrates include materials such as silicon, silicon nitride, glass, ceramics, plastics, insulating oxides, semiconductor materials, quartz, mica, metals, and combinations thereof. Pillars 14 can include insulating, semiconducting or conducting material and can be deposited and shaped by any method. Suitable methods for depositing such materials include photolithography, EB-induced and FIB-induced deposition. Working embodiments used FIB-induced deposition, and in particular examples FIB milling of deposited material was used to further refine the location, shape and size of deposited material. Pillars can be formed by directly depositing a metal in a defined location, or pillars can be formed by micromachining of a material on the substrate. FIB-induced deposition of gaseous metal precursors can be used to directly deposit a metal at a defined location. Similarly, FIB can be used to micromachine a metal on the substrate to give pillars of a desired size at defined locations.
[0036] Using FIB and/or EB techniques, gaseous precursors can be used to deposit a variety of useful metals on a substrate, such as those selected from the group consisting of Al, Au, Fe, Ni, Co, Pt, W, and combinations thereof. Gaseous precursors for EB- and FIB-induced deposition are known to those of ordinary skill in the art. Gaseous precursors can be selected from the group of gaseous or vaporizable materials that deposit a desired catalytic, insulative, semiconductive, or conductive material upon contact with a focused ion beam or an electron beam. For example, volatile organometallic precursors bearing reactive organic moieties can be used as gaseous precursors for EB- and FIB-induced deposition, with particular examples of such precursors including metal carbonyls, such as W(CO) 6 , and metal carbonyls of cobalt and nickel. Additional examples of volatile organometallic precursors for deposition include ferrocene, C 7 H 7 F 6 O 2 Au, (CH 3 ) 3 AlNH 3 , (CH 3 ) 3 Al, C 9 H 16 Pt, C 7 H 17 Pt, TMOS and TEOS. Working examples used C 9 H 16 Pt as a gaseous precursor for platinum deposition and ferrocene for iron deposition. Platinum is a particularly useful material because it is an excellent electrical conductor, and iron is useful as a catalyst for carbon nanotube growth.
[0037] With continued reference to FIG. 1 , step 16 indicates a coating process for depositing a layer of catalyst or catalyst precursor material on structure 10 to give structure 20 . Examples of suitable coating processes include sputter-coating and spin-coating. Arrows 21 indicate the deposition of catalyst or catalyst precursor material (catalytic material) to form a layer 22 of catalytic material at least on a top portion, and perhaps substantially over pillar 14 and on a top surface portion of substrate 12 . Coating 22 can be patterned by FIB to yield structure 30 , which has catalyst 22 localized on substantially a top portion of pillars 14 . Any technique capable of producing a desired pattern can be used in the patterning step. In working examples, pillars were patterned by FIB such that the width of each pillar ranged from about 250 nm to about 5 μm. However, pillars having smaller dimensions can be produced using an instrument having a smaller focused beam spot size, with current instruments capable of depositing pillars having a lateral dimension of about 50 nm.
[0038] Alternatively, structure 30 can be produced directly from structure 10 via step 18 by FIB-induced deposition of catalytic material 22 . After deposition, materials optionally can be patterned further using FIB or another technique to further refine their features.
[0039] Steps 28 and 32 both indicate nanotube synthesis. Step 28 uses conditions that yield substantially vertical nanotubes 34 synthesized in locations defined by sites having catalyst 22 and pillars 14 yielding structure 40 . Step 32 represents conditions for the synthesis of substantially horizontal nanotubes 36 , which yield structure 50 . Nanotubes 36 can be used to connect different sites on a substrate, for example, one or more pillars 14 .
[0040] Synthesis conditions can be selected such that nanotubes 34 and 36 are a single-walled nanotube, multi-walled nanotube, or a bundle of one or both types of nanotubes. Nanotubes can be synthesized using any suitable catalyst and conditions that allow localization of catalytic material in defined locations.
[0041] Numerous catalysts and protocols for nanotube synthesis are known in the art, and the present method can be used with any known or future developed catalyst that can be localized by selective deposition and/or milling. Typically, catalysts include a metal, such as Fe, Co, Ni, Ti, Cu, Mg, Y, Zn, alloys thereof, and combinations thereof. Generally, both elemental metals and their oxides can be used to synthesize nanotubes, for example, iron, zinc and oxides of iron and zinc are useful catalysts for nanotube synthesis. Particular catalysts and conditions for nanotube synthesis can be selected based on the type of nanotubes desired. For example, Dai '526 teaches chemical vapor deposition (CVD) conditions that are suitable for the synthesis of predominantly single-walled nanotubes. Other conditions, such as those disclosed by U.S. Pat. No. 5,500,200, issued to Mandeville, et al. (Mandeville '200), tend to yield predominantly multi-walled nanotubes. Mandeville '200 is incorporated herein by reference.
[0042] Other nanotube properties that can be varied by choice of catalyst and synthesis conditions include nanotube dimensions, such as length and diameter, and nanotube orientation relative to the substrate. For example, nanotubes may be synthesized such that they are substantially aligned with one another, meaning that most nanotubes point in substantially the same direction.
[0043] In working examples, nanotube diameters were from about 1.0 to about 1.8 nm for single-walled nanotubes, from about 1.5 nm to about 3.6 nm for double-walled nanotubes and from about 10 nm to about 200 nm for multi-walled nanotubes. However, smaller-diameter nanotubes can be prepared by varying reaction conditions. For example, a high concentration of hydrogen in the synthesis yields smaller diameter nanotubes. See, Dong et al., Effects of Hydrogen on the Growth of Carbon Nanotubes by Chemical Vapor Deposition. J. of Nanosci. and Nanotech. 2002, 2, 155-160, (Dong), which is incorporated herein by reference.
[0044] The catalyst can be localized by milling, selective deposition or both. For example, catalytic material can be deposited by a spatially selective technique, such as FIB-induced deposition or a spatially non-selective technique, such as sputter-coating, spin-coating, physical vapor deposition and/or electrodeposition. When a non-selective process is used, the present method confers spatial selectivity by using FIB to mill the catalytic material coating from the substrate, leaving catalytic material only in defined locations. In selected working examples catalytic material was deposited by spin-coating or sputter-coating and used for nanotube synthesis following FIB milling to produce the desired pattern.
[0045] One example of a liquid phase catalyst precursor (AlCl 3 .6H 2 O, SiCl 4 , FeCl 3 .6H 2 O, MoO 2 Cl 2 ) suitable for spin-coating the substrate is taught by Cassell, et al., J. Am. Chem. Soc. 1999, 121, 7975, (Cassell) and by U.S. Pat. No. 6,401,526, issued to Dai et al., (Dai '526), both of which are incorporated herein by reference. In a working example, such liquid phase catalyst precursors were spin-coated on the surface of a substrate, and the FIB was used to pattern the coating, thereby forming a pattern of catalyst-coated area. Thus, the catalyst coating can be patterned or milled such that the catalyst is in a defined location, such as on the top of metal pillars. Nanotubes can then be synthesized in defined locations. In one embodiment, individual catalyst particles on the substrate surface can be imaged using a high resolution FIB microscope or a dual beam FIB system having an electron microscope. Because individual catalyst particles can be visualized, individual particles can be removed. This approach enables precise catalyst milling so that a high-resolution catalyst array is produced.
[0046] FIG. 2A illustrates a field emission array, which uses nanotube field emitters as electron emission sources. Such nanotube field emitter arrays can be fabricated according to the method disclosed herein. In such an array, substrate 72 includes cathodes 74 , which can optionally be deposited and/or patterned according to embodiments of the method, connected to nanotubes 78 , which are synthesized using catalytic material 76 . Nanotubes 78 are substantially vertically aligned and directed at the anode (not shown), which is coated with phosphor. Nanotubes 78 preferably are synthesized under conditions that provide substantially vertically aligned nanotubes. If a method that does not provide selective synthesis of vertically oriented nanotubes is used, undesired nanotubes optionally can be removed via FIB-milling.
[0047] FIG. 2B depicts an array of substantially horizontal nanotubes 88 synthesized using catalyst 86 and connecting pillars 84 formed on substrate 82 .
[0048] FIG. 2C depicts a nanotube transistor device 90 . Source pillar 94 and drain pillar 97 are deposited on insulating substrate 92 to provide connection to underlying source and drain circuitry, respectively (not shown). Gate 95 is formed by depositing a metal on the insulating substrate 92 having gate circuitry (not shown). Catalytic material 96 is deposited on source 94 and drain 97 , and nanotube 98 is synthesized therebetween. Alternatively, catalytic material 96 is deposited on only one of source 94 or drain 97 prior to nanotube synthesis with the nanotube being synthesized between the source and the drain so that the source and drain are electrically connected. Even though the site of nanotube synthesis is defined by the catalyst locations the direction of nanotube growth is not necessarily predetermined and thus nanotubes may be synthesized that do not connect the two desired points. However, with respect to FIG. 2C , for example, nanotubes that do not connect source 94 and drain 97 can be removed via FIB milling so that only the nanotubes having the desired connectivity remain.
[0049] Device 90 is one example of a device that can be assembled according to the method disclosed herein. Other devices will be readily apparent to those of ordinary skill in the art in view of the present disclosure. For examples of transistors using nanotubes, see: Tans et al., Nature, 1998, 393, 49; and Collins et al., Science, 2001, 292, 706-709, both of which are incorporated herein by reference.
[0050] FIG. 3 illustrates second method for synthesizing nanotubes in defined locations. With reference to structure 100 , catalytic material 104 is deposited at defined locations on substrate 102 via FIB-induced deposition. Nanotubes can be synthesized in the locations defined by the catalytic material 104 according to steps 106 or 108 , which represent protocols for substantially vertical nanotube synthesis and substantially horizontal nanotube synthesis, respectively.
[0051] FIG. 4 depicts the preparation of an exemplary nanotube field emitter device 130 . Specifically, V-shape 122 represents a tungsten filament, attached to molybdenum posts 124 , inserted through ceramic base 126 . Tungsten was chosen for V-shape 122 in working embodiments because it is a refractory, high melting point, relatively inert material. Moreover, tungsten can be shaped by, for example, electrochemical sharpening, to give a sharpened tip. In working embodiments molybdenum was used for posts 124 , because it is a high melting point, dimensionally stable, machinable material. However, other materials having similar properties also can be used for posts 124 . Catalyst can be selectively deposited on the tip of V-shaped filament 122 via FIB-mediated deposition. Nanotube 132 can be synthesized on the catalyst-coated tip to yield nanotube field emitter 130 . In operation, structure 130 is a high brightness, high-aspect-ratio, field emitter, which uses nanotube 132 as an electron emission source. Using a nanotube as the field emission cathode results in a smaller virtual source size, and the nanotube field emitter device 130 is useful, for example, as a source for a field emission microscope. Jiao et al., characterized the electron field emission properties of such a field emitter. See, Mat. Res. Soc. Symp. Proc. 2002, 706, 113-117, which is incorporated herein by reference.
[0052] Unless otherwise specified, nanotubes were synthesized according to the present procedure under CVD conditions as is known to those of ordinary skill in the art. CVD, by itself, is a spatially non-selective process. However, features of the present method render CVD spatially selective, and in working examples, CVD is used to selectively synthesize nanotubes in defined locations. Thus, in one aspect, FIB patterning of a catalyst confers selectivity upon the synthesis of nanotubes using CVD.
[0053] Working embodiments used the following CVD procedure. First, a substrate having a catalyst patterned thereon was inserted into the CVD reaction chamber. The reactor was evacuated by a mechanical pump, with working embodiments evacuating to a base pressure of 3×10 −2 torr. A quartz tube CVD chamber was used in working examples; however, any CVD reaction chamber can be used. The substrate was heated sufficiently to activate the catalyst, such as to a temperature of 700° C. Gas purging also is typically used to facilitate catalyst activation. Gases suitable for purging include ammonia, hydrogen, nitrogen and argon. In working embodiments hydrogen gas was introduced into the heated reaction chamber at 325 standard cubic centimeters per minute (sccm) for 15 minutes. The substrate temperature was then increased to 800° C. as measured by a thermocouple. At this temperature, an admixture of acetylene and hydrogen at a volume ratio of 1:13 was introduced into the reactor. Acetylene functions as a carbon source and other carbon sources are well known and can be used in conjunction with features of the present method. Examples of other suitable carbon sources include, without limitation, methane, methanol, ethane, ethanol, ethylene and the like. Working embodiments used either methane or acetylene. Without limitation to theory, it is believed that the hydrogen gas introduced with the carbon source acts as a diluent for the carbon source and prevents catalyst poisoning by excess carbon. When complete catalyst poisoning occurs, typically few or no nanotubes are synthesized. When partial catalyst poisoning occurs, other species, such as amorphous carbon is produced. The flow rates of acetylene and hydrogen were kept at 25 sccm and 325 sccm, respectively, for 15 minutes. The total pressure in the reactor during nanotube growth was 76 torr. These specific conditions are exemplary only and can be varied as is known to those of ordinary skill in the art.
[0054] These conditions primarily yield multi-walled nanotubes, which are preferred for a single nanotube field emitter device. Generally, diameters of multi-walled nanotubes ranged from about 10 nm up to about 200 nm in working examples; however, multi-walled nanotubes having diameters of from about 8 nm up to about 1 μm can be prepared. In some cases methane was used as the carbon source for nanotube synthesis. When methane was used as the carbon source, single-walled and double-walled nanotubes were prepared in the same synthesis. The diameter of single-walled and double-walled nanotubes produced was in the range from about 1.0 to about 1.8 nm and from about 1.5 to about 3.6 nm, respectively. However, single walled nanotubes can be produced having diameters of from about 1 to about 10 nm and double walled nanotubes can be produced having diameters from about 1 to about 20 nm.
EXAMPLES
[0055] The following examples are provided to illustrate certain particular embodiments of the disclosure. It should be understood that additional embodiments not limited to those particular features described are consistent with the following examples.
[0056] Each of the following examples was performed using a FEI FIB 611 system.
Example 1
[0057] This example describes FIB-induced deposition of Pt pillars. Images of the pillars prepared according to this example are shown in FIG. 7 . In this process, the Pt pillars were deposited on a silicon substrate by injecting a gaseous compound (C 9 H 16 Pt) via the capillary needle-sized nozzle of the gas-injection apparatus. A current of 2 picoamperes (pA) was used, the magnification of deposition was 20,000×, and the pillars were patterned in a box radius of 0.03 micrometers (μm), using a 99% overlap within each box. The deposition time was 5:00 minutes per pillar deposited in series.
Example 2
[0058] This example describes FIB-induced deposition of Pt pillars. In this process, the Pt pillars were deposited on a substrate by injecting a gaseous compound (C 9 H 16 Pt) via the capillary needle-sized nozzle of the gas-injection apparatus. A current of 6 pA was used, the magnification of deposition was 10,000×, and the pillars were patterned in a box width of 1.0 μm with a 50% overlap within each box. To deposit the pillars evenly, the substrate was rotated 180° relative to the source after 5:30 minutes, 3:30 minutes and 1:30 minutes for each pillar deposited in series.
Example 3
[0059] This example describes deposition and patterning of a catalyst on the pillar arrays prepared according to Example 1. The patterned substrate of Example 1 was coated with a thin layer of Co via sputter-coating for 90 seconds at 32 milliamperes (mA). The Co coating was patterned via FIB sputtering (500 pA), such that Co remained only on the top pillar surfaces. The FIB-patterned substrate was then placed in a CVD reactor, and carbon nanotubes were synthesized by the catalytic thermal decomposition of acetylene.
Example 4
[0060] This example describes coating a substrate using a liquid catalyst precursor. The liquid catalyst precursor was prepared according to the procedure of Cassell et al. J. Am. Chem. Soc. 1999, 121, 7975. The catalyst precursor contained inorganic chloride precursors (AlCl 3 .6H 2 O, SiCl 4 , FeCl 3 .6H 2 O, MoO 2 Cl 2 ), a removable triblock copolymer (P-103) serving as the structure directing agent for the chlorides, and an alcohol mix (EtOH/MeOH) for dissolution of the inorganic and polymer compounds. The liquid catalyst precursor was then spin-coated on the surface of a porous silicon substrate. A 25 microliter (μL) aliquot of liquid catalyst precursor was deposited on the surface of the substrate. After 30 seconds the substrate was spun at 5,000 rpm for 5 seconds to spin-coat the substrate. A second 25 μL aliquot of catalyst precursor was then delivered to the substrate while spinning for 5 more seconds at 5,000 rpm. The substrate was baked at 75° C. for 15 minutes. The focused ion beam was then used to sputter the substrate surface to create a pattern in which some areas remained coated with catalyst and others did not. The substrate was placed in a CVD reactor, and carbon nanotubes were synthesized by the catalytic thermal decomposition of acetylene.
Example 5
[0061] This example describes the preparation of a 3×4 array of Pt pillars with an indentation in the top surface of each pillar. The indentations are useful for controlling the direction of nanotube growth.
[0062] A 3×4 array of pillars was deposited using a current of 5 pA, a dwell time per beam step of 5.0 μs, 99% beam diameter overlap per step and using an approximately 7 μm field of view magnification. Following deposition of the array, an indentation was milled in the top of each pillar using the same conditions as the deposition, except a 0.5×0.5 μm filled box pattern was used, and each indentation was milled for 30 seconds. FIGS. 6A and 6B show the array and a representative member, respectively. Such pillars having indentations aid the synthesis of substantially aligned nanotubes.
Example 6
[0063] This example describes the FIB-mediated deposition of iron for nanotube synthesis using ferrocene as a gaseous precursor. Prior to iron deposition the silicon substrate was ultrasonically cleaned in acetone for 15 minutes. After drying, the substrate was mounted on an aluminum sample holder using copper tape and placed into the FIB apparatus. Ferrocene powder was inserted into a gas injection crucible that is connected to a needle placed inside the vacuum chamber of a FEI 611 FIB apparatus. The gas injection needle was aimed at the silicon substrate and the crucible was heated to 48° C. To deposit a 1 μm by 1 μm area of iron beam current was maintained at 64 pA, the dwell time per beam step was 0.6 μs, the beam diameter overlap per step was 0%, and the distance (d) from needle to substrate was 100 μm. Iron pillars having various dimensions were deposited by this procedure using different parameters. For example, 3 μm by 3 μm pillars were deposited using a beam current of 500 pA, a dwell time per beam step of 0.5 μs, a beam diameter overlap per step of 0% and d was 100 μm.
Example 7
[0064] This example describes a method for assembling carbon nanotube field emitters by directly synthesizing carbon nanotubes on the tip of a sharpened tungsten wire. Pure tungsten wire of 0.1 mm diameter was electrochemically sharpened to a tip diameter on the order of 1 μm, using a 2.5 M solution of KOH—H 2 O, with a nickel strip as a cathode. A voltage source and a multimeter were connected to the circuit, which passed a current through the tungsten tip as it was suspended in the solution. After a survey of various voltages, it was determined that the most sturdy tip geometry seems to result with 15V. At this voltage, the reaction rate between the tungsten and the KOH solution was the most rapid. After approximately 2.5 minutes, the submerged section of tungsten fell off and the current dropped sharply, at which point the tungsten tip was removed.
[0065] The sharpened tip was spot-welded to a V-shaped tungsten wire where it had been spot-welded to a field-emission-microscope base of ceramic or glass. This assembly would serve as the substrate for the carbon nanotube emitters.
[0066] To grow carbon nanotubes on this substrate, the sharpened tungsten tip was carefully dipped into a liquid catalyst containing EtOH, MeOH, AlCl 3 .6H 2 O, SiCl 4 , FeCl 3 .6H 2 O, MoO 2 Cl 2 , and P-103 (a removable triblock copolymer). The substrate was then inserted into the chemical vapor deposition reactor. The nanotube growth was accomplished by the catalytic decomposition of acetylene with a flow rate of 25 sccm. The reaction chamber was kept at 76 torr and the temperature of the reaction stage was maintained at 800° C.
[0067] Field emission characteristics of field emitters made according to this example are provided by FIGS. 5A and 5B . The field emission experiments were performed in a field emission microscope (FEM) system with a base pressure of ˜1×10 −9 Torr. The typical pressure in the FEM chamber during the measurement was ˜1×10 −7 to 10 −8 Torr. The FEM configuration has a point-to-plane electrode geometry. For the anode, a glass plate covered with indium-tin-oxide (ITO) was used, with a layer of phosphor deposited over the ITO. The distance between the nanotube emitters (cathode) and the phosphor screen (anode) was approximately 12 cm. The tungsten filament support (carbon nanotube emitter substrate) was attached to a current-regulated heating supply to clean the field emitter. The field emission images and the current-voltage (I-V) behaviors of the nanotube emitters were obtained by applying a negative dc voltage up to 3,000 V. Emission current measurements were recorded using a digital data acquisition software (Test-Point) in a personal computer, which allows construction of both a time-averaged I-V response and current versus time plot at each voltage. The field emission images produced on the phosphor screen were imaged using a digital camera and recorded continuously on videotapes. See, Jiao et al. Mat. Res. Soc. Symp. Proc. 2002, 706, 113-117.
Example 8
[0068] This example describes the synthesis of nanotubes using different conditions and the correlation of their resulting different internal structures with their field emission properties. Nanotubes were synthesized on the substrates according to the CVD procedure discussed above. The internal structures of the nanotubes were analyzed by high-resolution transmission electron microscopy (HRTEM), and the field emission characteristics of nanotubes characterized by a field emission microscope.
[0069] Analysis of the internal structures of the nanotubes by HRTEM revealed that the nanotubes synthesized using iron, cobalt and nickel with the introduction of hydrogen during the nanotube growths had an average diameter of about 10 nm. However, the nanotubes formed using iron and cobalt catalysts exhibited better graphitization (crystallization of carbon) than the nanotubes prepared using nickel. The material prepared using iron without introduction of hydrogen gas during the synthesis included amorphous carbon particles as well as carbon nanotubes. The nanotubes formed under the hydrogen-free conditions had an average diameter of about 45 nm. Specifically, the nanotubes prepared using iron catalysts in the presence of hydrogen comprised straight graphite layers aligned parallel to the tube axis. Moreover, little amorphous carbon was observed on the outer surface of the nanotubes. Field emission characteristics of carbon nanotubes prepared by different catalysts are quite different. As indicated in Table 1, carbon nanotubes synthesized with the presence of iron catalyst exhibited a low turn-on field and a low threshold field.
[0000]
TABLE 1
Type of nanotube
Turn-on field
Threshold field
Amplification
(catalyst used)
(V/μm)
(V/μm)
factor
Fe
0.35
2.8
2300
Co
0.4
3
2600
Ni
5
9
1500
Fe (without using
9
14
700
H 2 )
Example 9
[0070] This example describes the formation of ZnO nanowires on tungsten substrates. Such nanowires are useful as field emitter devices. Using a vapor transport method, ZnO nanowires were selectively synthesized on tungsten tips and on tungsten plates. In both cases a thin film of Au catalyst was deposited and patterned in desired locations. The angular intensity and fluctuation of the field emission current from the ZnO nanowires synthesized on tungsten tips was similar to those observed for similar field emitters prepared using carbon nanotubes. A self-destruction limit of about 0.1 mA/sr for angular intensity was observed, and the power spectra showed a 1/ƒ 3/2 characteristic from 1 Hz to 6 kHz. See, Dong et al. Appl. Phys. Lett. 2003, 82, 1096-1098.
[0071] The present invention has been described with reference to preferred embodiments. Other embodiments of the invention will be apparent to those of ordinary skill in the art from a consideration of this specification, or practice of the invention disclosed herein. It is intended that the specification and examples be considered as exemplary only, with the true scope and spirit of the invention being indicated by the following claims. | A method is disclosed for directly synthesizing nanoscale structures, particularly in defined locations. The method overcomes problems in nanoscale manufacturing by enabling the direct fabrication of composites useful for constructing electronic devices. In one aspect of the method, nanotubes and arrays of nanotubes are synthesized directly at defined locations useful for constructing electronic devices. | 2 |
CROSS REFERENCE TO RELATED APPLICATIONS
This application is a continuation-in-part of Ser. No. 07/763,490, filed Sep. 23, 1991, now U.S. Pat. No. 5,426,620, which is a continuation-in-part of Serial No. 07/316,541, filed Feb. 28, 1989, now abandoned, which is a continuation of Ser. No. 07/029,245, filed Mar. 23, 1987, now abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a load control and management apparatus for controlling the load demand and operation of electrical energy-consuming equipment. More particularly, the present invention relates to a control and management apparatus for electrical power networks that allows individual control of electrical loads of energy-consuming equipment on the network. The unique apparatus of this invention optimizes the performance of the individual equipment while precisely initiating, controlling, and synchronizing its individual load activities with the energy supplied thereto, so that the life and efficiency of the equipment is enhanced while overall load demand is controlled.
The apparatus has been shown to provide significant overall energy savings when used on equipment with normal reserve capacity, such as air conditioning and refrigeration units and heat pumps. These energy savings can be achieved without the sacrifice of any reliability, durability, or performance standards of the equipment. As an example, the same house can be kept just as cool, relative to outside temperature, using the same air conditioner with less energy consumption when the unique apparatus of the instant invention is employed.
In addition, the improved apparatus disclosed herein is capable of being controlled and synchronized by the power company, over its own lines, without the use of superimposed or atmospherically transmitted radio frequency signals. The power company is therefore freed from the whims of its customers in a way never before possible and, at the same time, is freed from the radio frequency noise regulations of the Federal Communications Commission.
The fields most likely to benefit from the advantages of this invention are the basic industry of electrical power generation and all the many and diverse fields that use electrical equipment. The major benefactors among the fields of users will be the refrigeration, heating and air conditioning industries and all users of such equipment. 0f course, any reduction in the overall electrical power needed by an area tends to benefit the ecology of that area by virtue of reducing local air and water pollution.
Thus it can be seen that the potential fields to benefit from this invention are myriad and the particular preferred embodiments described herein are in no way meant to limit the use of the invention to the particular field chosen for exposition of the details of the invention.
A comprehensive listing of all the possible fields to which this invention may be applied is limited only by the imagination and is therefore not provided herein. Some of the more obvious applications are mentioned herein in the interest of providing a full and complete disclosure of the unique properties of this previously unknown general purpose article of manufacture. It is to be understood from the outset that the scope of this invention is not limited to these fields or to the specific examples of potential uses presented hereinafter.
2. Description of the Prior Art
Electric utility companies supply power to many individual customers. The sum total of the demand of the individual customers is the aggregate demand seen at the generation plant of the utility. At certain daily and seasonal times, customer demand is higher than at other, "off-peak" periods. The basic utility problem is that the company must have sufficient capacity at the "peak" periods to satisfy maximum customer demand or load requirements. This maximum capacity is far in excess of that required for normal off-peak periods. The electric company is therefore required to build and maintain entire power generation plants that serve no function other than to meet peak period demands. It is estimated that the cost of building a new generating facility is $6,000 to $10,000 per kilowatt of production capacity, whereas the cost of saving those same kilowatts of capacity by using my demand control apparatus is on the order of $200 per kilowatt of capacity, supplied from demand side management.
Electric companies customarily use a demand charge as well as the regular schedule of rates for energy, this demand charge being generally based upon the highest average kilowatt demand occurring during a predetermined interval of, say, 10-15 or 30 minutes, during some longer period of time, say, one month. It is therefore evident that a consumer whose demand charge increases because of a high average kilowatt demand, during a tiny interval of say 15 minutes in one month, will obviously be desirous of controlling his power demand and limiting it to the lowest value practicable. In simple terms, one pays most for electrical energy if they use it at the fastest rate. The total of kilowatt-hour usage and the highest demand reading over a billing period determine the total charges to the customer. Surprisingly, the demand charge on an electric utility bill is sometimes the higher of the two costs involved. Even more surprising is the fact that many consumers are not even aware their electric bill is computed in this manner| By instituting demand charges the utility companies have attempted to shave the peaks from energy load requirement cycles by imposing a financial penalty on users who consume heavily during short, peak periods. Large users are thus encouraged to level out their energy consumption so as to be constant during all time periods. The approach is somewhat of a shell game because the individual user's peak periods do not always coincide with the peaks seen by the power company at the central power station. Note that if all the large users shifted their peak demands to a different time of day, then that time of day automatically becomes the peak demand time as seen at the central generating station. The demand charge system does nothing to prevent this sort of thing from happening. The main problem with this approach is that when people need power they need power, and the fact that they could get it cheaper by getting it later is irrelevant. One could even say, the main problem with this approach is that it simply does not work. In any case, the financial incentive route has not been entirely successful as a method of reducing peak electrical energy demands.
There have been many attempts to reduce electrical energy-consuming equipment demand, particularly during "peak" periods, as metered by the utility company, These previous methods usually involve programmed timers or microprocessors which shut off equipment during a portion of each metered interval so that demand is reduced and the utility meter reads less demand during that interval. In other words, if a metered demand interval is of a fifteen minute duration and if, during successive fifteen minute intervals, a machine is shut off for some portion of each interval, the reading of the utility meter will reflect a lower demand during each interval, and the demand charges will be lower.
Devices for reducing electrical demand during certain times are old and well known in the art. Many, if not all, of these systems use the brute force technique of simply cutting the main source of power to an individual piece of energy consuming equipment with some sort of time activated switch. It has been found that brute force cyclic power interruption significantly shortens the life of many types of expensive electrically powered mechanical equipment. A prime example is the main compressor unit on a refrigeration unit. Such a compressor must be run through predetermined and important shutdown (pump down) and startup cycles to prevent serious damage. Simple power cutoff devices simply have no way of allowing these shutdown and startup cycles to occur as designed into the equipment.
Recently, the need for some sort of control, other than financial incentive, of the demands on power utility networks has become acute. As a result, numerous power cutoff or cycling systems have been developed for installation at individual user sites. These generally are crudely controlled switching devices installed in the primary supply power line ahead of the equipment to be controlled. These crude main power cutoff devices have the same effect as pulling the plug on the equipment being controlled and are referred to as "plug pullers" throughout the remainder of this discussion. For example, a timed switch may be installed on an electrical hot water heater which switches off power to the heater elements during periods of the day when people are not likely to have a need for hot water. The control of these switches is done with simple day timers in the crudest of these devices, and may be accomplished from the utility, using radio frequency signals, on more sophisticated devices. The actual switches normally operate to simply remove the power from the equipment for, say, a couple of hours during the evening, or they may initiate a pulsing action which cycles the power on and off during the controlled time period and allow normal operation at all other times. The following known prior art has been directed to providing such crude cutoff controls for electrical equipment. As will be seen, the sophistication, simplicity, and effectiveness of my invention is not rivaled in the prior art.
U.S. Pat. No. 4,141,407, issued to Briscoe et al. on Feb. 27, 1979, shows a power demand limiting circuit for an air temperature control apparatus coupled with a source of municipal power through a demand meter. A timer is programmed to cycle a timer switch off at least once during any period determined to be a demand period by a utility wattmeter. The timer switch is arranged on the main power input to all loads and thus is a brute force "plug puller" as defined above. The timer switch is incapable of any sort of external control, short of manual activation of an override switch which disables the entire unit. Briscoe et al. disclose a power demand limiting circuit which utilizes a programmable timer in conjunction with selector switches which manually select air conditioning or heating during some portion of a metered demand interval. The continuous connection of the timer to the power source forms an additional parasitic power drain of its own.
By contrast, the control apparatus of the instant invention is wholly installed in the control signal line of the thermostat of each individual load and thus is not a brute force "plug puller". The most glaring difference is connecting a separate demand control process apparatus wholly within a control power line at the point of control of each load; Briscoe clearly teaches a demand control process apparatus within the supply power line. It should be emphasized that switching of the thermostatic control line, within or directly adjacent to the equipment, is not the equivalent of switching off the main supply power line. The control switch of the instant invention is controlled and cycled by a digital pulse counter instead of a crude "timer", thus leading to load initiation and synchronization benefits not possible with a crude timer device as shown by Briscoe et al.
By further contrast, the instant invention is capable of external control through ambient condition sensing devices or through frequency change sensing internal devices capable of being activated by the electric utility company. Such external control is not even suggested by the Briscoe et al. device. Also, the instant invention does not create a continuous parasitic power loss as would the timer of Briscoe et al.
U.S. Pat. No. 4,027,171, issued to Browder et al. on May 31, 1977, shows a power demand limiting system for limiting the peak power demand of space conditioning loads coupled with an electrical utility power supply by space temperature responsive switching means. The system includes timer means for cyclically coupling and uncoupling the space conditioning load with the electric utility power supply through the space temperature responsive switching means, and timer control means for selectively energizing and de-energizing the timer means. Browder et al. state that the cyclic control switch may be crudely controlled (disabled or enabled only) by the electric utility. The cyclic periods of Browder et al. cannot be adjustably controlled, either manually, remotely, or by any other means.
By contrast, the device of the instant invention does not use a timer for cycling the switch but rather uses a digital recycle counter which allows for precise orchestration of the startup of the many individual loads that may be on the overall network. Also, in contradistinction with Browder et al., the instant invention allows the external control of the cyclic periods of the cyclic switch. The cyclic periods of the instant invention may be adjusted either with a local ambient condition sensor or with a line frequency change sensing device controllable by the utility company. In addition, Browder et al., although envisioning simple activation of the timer switch by remote control from the electric utility, does not in any way teach the power line frequency change responsive control of the instant invention. A major difference is the instant invention is always on line cycling the load in the optimum run modes, and allows interaction of the electric utility to alter the length of optimum run periods.
By way of historical interest, U.S. Pat. No. 1,503,130, issued to Moore on Jul. 29, 1924, shows an electrical apparatus for automatically controlling peak demands. It is interesting to note that, even at this early date, power companies were experiencing problems with peak demand periods overloading their electrical generating equipment. The apparatus of Moore regulates the load absorbed by an electrode furnace by retracting the electrodes with an electrode motor. The null point of the regulatory apparatus is changed so as to reduce the load by retracting the electrodes at such time as the energy used exceeds a given amount in a 15 minute time period. The system is designed for use on equipment with finely tunable load consumption characteristics, such as an immersible electrode metallurgical melting furnace. As such, the regulatory apparatus is not suited to the purposes of the instant invention. The patent does not hint at or disclose any apparatus for on-off cycling of the load, let alone any externally controlled variation of those cyclic periods.
By contrast, the device of the instant invention does not use a timer for cycling the switch but rather uses a digital recycle counter in the control signal line of the load, which allows for precise orchestration of the startup of the many individual loads that may be on the overall network. Also, in contradistinction with Moore, the instant invention allows the external control of the cyclic periods of the cyclic switch. The cyclic periods of the instant invention may be adjusted either with a local ambient condition sensor or with a line frequency sensing device controllable by the utility company. In addition, Moore does not in any way teach the utility-activated power line frequency change responsive control of the instant invention. Also, the continuous connection of the timer to the power source forms an additional parasitic power drain of its own.
U.S. Pat. No. 1,873,238, issued to Wood on Aug. 23, 1932, shows an off-peak power and metering system and apparatus. The patented device disconnects an electrical water heater load from the source during predetermined peak periods of the day. As such it is another "plug puller" as described previously. The patent slows the power metering device during off-peak times of day so as to effectively give the consumer more power for the same money during those times. There is no mention or contemplation of demand charge reduction in Wood. The patent does not hint at or disclose any apparatus for short period on-off cycling of the load during either the peak or off-peak periods, let alone any externally controlled variation of those cyclic periods.
By contrast, the device of the instant invention does not use a timer for cycling any sort of switch, but rather uses a digital recycle counter which allows for precise orchestration of the startup of the many individual loads that may be on the overall network. Also, in direct contradistinction with Wood, the instant invention allows the external control of the cyclic periods of the cyclic switch. The cyclic periods of the instant invention may be adjusted either with a local ambient condition sensor or with a line frequency sensing device controllable by the utility company. In addition, Wood does not in any way teach the utility-activated power line frequency responsive control of the instant invention. In addition, the continuous connection of the timer to the power source forms an additional parasitic power drain of its own. As a last distinction from Wood, the instant invention does not in any way alter the power measuring characteristics of the power meter, but rather slows up the average use of power by the load. Present day regulations prohibit any alteration of the power meter.
U.S. Pat. No. 3,296,452, issued to Williams on Jan. 3, 1967, shows a load regulation device for the maintenance of electric loads within the limits on which demand rates are based. The patent proposes an alarm to be sounded as the energy consumed by a process approaches the maximum allowed during any given demand interval of, say, 15 minute duration. Equipment operators would shut down the equipment for the remainder of the demand period upon hearing the alarm. Williams suggests that automatic shutdown of the equipment could be accomplished in lieu of the alarm, but no means for accomplishing this function are disclosed. The scheme allows for energy to be consumed at a greater rate during the beginning of the demand interval with the stop alarm becoming more sensitive to the straight line demand curve near the end of the demand interval. The system of Williams, although relatively sophisticated, is in the final analysis simply a "plug puller" as discussed above. Of primary interest is Williams' use of digital pulse counters similar to the pulse counters used by the instant invention. However, Williams uses the digital pulse counters in an entirely different way and for a different purpose than the instant invention, and his pulse counters are in no way responsive to automatic external variation.
By contrast, the control switch of the instant invention is installed in series with the control signal line of a thermostat or other environmentally sensitive sensor, and thus is not a brute force "plug puller". It should be emphasized that switching of a thermostatic control line, within or directly adjacent to the equipment, is not the equivalent of switching off the main power line. Also, in contradistinction with Williams, the instant invention allows the external control of the cyclic periods of a cyclic switch. The cyclic periods of the instant invention may be adjusted either with a local condition sensor or with a line frequency sensing device controllable by the utility company. In addition, Williams does not in any way teach the utility-activated power line frequency responsive control of the instant invention.
U.S. Pat. No. 3,496,337, issued to Voglesonger on Feb. 17, 1970, shows a sequencing circuit for power consuming devices. The patent shows a series of heating elements with individual thermostatic controls. The total current to the ensemble is monitored by an ammeter with a high and low limit switch built in. As long as the total current is below the preset maximum, mechanical timers sequentially introduce further heating elements to the line. If the maximum current is exceeded, the introduction of further heating elements is inhibited. This control device is another "plug puller" as previously discussed. There is no switching introduced into the thermostatic control lines, let alone an externally controlled, synchronized, variable period, cycling of those lines as disclosed by the instant invention.
U.S. Pat. No. 3,677,335, issued to Weatherston on Jul. 18, 1972, shows a staged heating and cooling system. The patent proposes a control system for a heating and cooling system in which the amount of heating and the amount of cooling are both controlled in timed incremental stages by means of a signal from an up-down electronic counter which operates to call for the next successive stage at timed intervals in accordance with an electronic clock. The patented scheme, basically, is to successively turn on more individual heating or air conditioning units at, say, two minute intervals until a desired temperature level of an enclosure has been reached. The device is not similar in function or structure with the instant invention. It essentially discloses a fancy single thermostat which is plugging in or disconnecting a group of related equipment. Of interest, only, is the teaching that binary up-down pulse counters were known prior to my invention in the field of heating and air conditioning.
U.S. Pat. No. 4,208,593, issued to Sullivan on Jun. 17, 1980, shows a method and system of selective disconnection of loads for a power source. The primary thrust of the patent is the provision of a redundant demand control device which will function to disconnect individual loads and sound an alarm in the absence of power to the primary demand controller itself. The patent teaches the prioritizing of individual equipment at a particular meter location and a brute force removal of the power supply from a low priority piece of equipment in case of a demand overage. By contrast, the instant invention sequences the initialization of load operation. Sullivan teaches no cycling of an individual equipment control, such as a thermostat signal, let alone the provision of an externally controlled variable cycle period.
U.S. Pat. No. 4,245,319, issued to Hedges on Jan. 13, 1981, shows an energy management method and apparatus utilizing duty cycle reduction synchronized with the zero points of the applied voltage. Hedges shows another "plug puller" apparatus which only reacts when a sensed demand limit is being approached. The device sheds certain sensed loads to keep the demand just below this demand limit. Hedges teaches no cycling of an individual equipment control, such as a thermostat signal, let alone the provision of an externally controlled variable cycle period.
These known methods and systems, however, do nothing to prevent damage to the equipment and its components from continuous random on/off operation (plug pulling), which shortens the life of the equipment and increases maintenance and repair expense. None of the prior systems or devices take into account the diverse electrical load requirements for the individual components within one piece of equipment. None of the known methods control and initiate startup of the equipment in universal synchronization with the electrical energy being supplied. A change in the metered interval, such as after a power outage, causes the timing of these methods to be "out of sync" with the metered demand intervals. The previous methods and systems must use additional devices, such as the time delay relays of Briscoe et al., to preclude the equipment from creating a demand surge or overload by simultaneous energization after an outage. None of the prior methods or systems precisely control the operation of the equipment so that it functions in an optimum window for the most efficient performance possible by that particular equipment. None of the previous methods, systems or devices assist in reducing demand by using no energy at all during a significant portion of the operating cycle. They must always be energized in order to function, thereby creating their own continuous load demand.
It can thus be seen that previous systems, methods and devices for load demand reduction are inadequate, and most simply "pull the plug" of a machine to reduce its load demand. This may or may not reduce demand. However, none of the previous methods and systems control and manage load demand, and none control and manage the operation of the equipment or individual subsystems of a complex piece of equipment.
None of the above inventions and patents, taken either singly or in combination, is seen to describe the instant invention as claimed.
SUMMARY OF THE INVENTION
Briefly, the invention comprises a specially controlled switch in the control signal line of individual units of electrical equipment. An example of a control signal line is the thermostat control line on a standard air conditioning unit. The special switch is opened at certain intervals so as to effectively signal the equipment that the sensor providing the control signal has been satisfied. When an AC control signal is sent down the signal line by the equipment control (thermostat), a digital counter is activated which holds the special switch open (off) until a predetermined number of AC pulses have occurred. The special switch is then closed (on) until a second predetermined number of AC pulses have occurred and then the open-closed cycle is repeated or recycled. The type of counter used to control this type of cyclic switching activity is known in the art as a digital recycle counter. The digital recycle counter itself is a conventional and commercially available item. The subject of this patent is not the recycle counter itself, but rather the combination of such a recycle counter with the conventional control line of an electrical load. This cycling of the special switch from open to closed and back again continues as long as there is a control signal present in the signal line (e.g., as long as the thermostat is calling for cooling). When there is no control signal in the signal line (e.g., the thermostat switch is open and no cooling is called for), the digital counter is rendered inactive and its activity will begin anew when a signal is again present.
No energy is consumed by the device unless the electrical control signal line of the equipment is activated. Each time the control signal line is activated the counter first causes an off cycle to be maintained for a certain number of counts, and then an on cycle to be maintained for a certain number of counts. The off cycle and the on cycle are repeated for as long as the control signal line is activated. If the control signal line is deactivated (as by the thermostat switch opening) all counting ceases and the off-on cycles are begun again when the signal line is again activated.
The actual counts being totalized by the digital counter are derived from the voltage peaks in the AC signal line. The number of counts in the off cycle and in the on cycle can each be manually and individually adjusted at a given application site by the setting of DIP switches on an external face of the physical counter unit. A digital optical system responsive to a hand held digital optical transmitter may alternately be used to set and change the pulse count of the cyclic periods.
The off counts and the on counts are set to the optimum values for equipment efficiency under normal operating conditions by manually setting the DIP switches or sending an optical digital code from a hand held transmitter upon installation of the equipment at the given facility. In addition, the digital counter is capable of varying the pulse counts for each cycle based upon the signal from an external source. This variation of the normal pulse counts in each cycle is normally done only in extreme or abnormal circumstances. For example, when an external thermometer indicates that it is very hot or cold outside, the counter is capable of increasing the number of counts in the "on" cycle so as to provide more total cooling or heating capacity, respectively. As another example, when network demand is very heavy, it is possible for the utility to increase the counts in the "off" cycle. The changing of the pulse count cycle by the utility is effected by a line frequency sensor built into or external to the digital counter. Since the line frequency of the power provided over the power lines is under the precise control of the utility company, a means has been provided for the synchronized shedding of peak loads without interrupting the power flow to any customers.
In the example of the control signal line being the line from the thermostat in an air conditioning system, the absence of a control signal voltage in this line normally indicates to the equipment that the air temperature is cool enough for the main refrigeration compressor to be shut down. When the control signal voltage is again present in the thermostat line a normal startup sequence is initiated by the air conditioning equipment. When the special switch is opened the equipment reacts exactly as though the thermostat has been satisfied and the normal refrigeration shutdown sequence is initiated. The special switch of this invention is installed in series with the thermostat switch in the thermostat line at a point as near the equipment load as is possible. It is contemplated that the special switch of this invention could actually be built into an original air conditioning unit. The small size of the invention makes it equally attractive to retrofit existing units.
Accordingly, it is a principal object of the invention to provide a new and improved electrical load optimization device which overcomes the disadvantages of the prior art in a simple but effective manner.
It is a major object of the present invention to provide a superior means for controlling individual load requirements and operation of energy-consuming equipment by imposing a precise optimum run operation on the equipment in universal synchronization with the energy being supplied thereto.
Another object of the invention is to provide a device for initiating, synchronizing and optimizing the operation of individual equipment which is simple and inexpensive to manufacture.
Another object of the invention is to provide a device for initiating, synchronizing and optimizing the operation of individual equipment which is simple and inexpensive to install.
Another object of the invention is to provide a device for initiating, synchronizing and optimizing the operation of individual equipment which is normally fully automatic, therefore requiring no user intervention.
Another object of the invention is to provide a device for initiating, synchronizing and optimizing the operation of individual equipment which requires no alteration of the existing equipment or components of the equipment.
Another object of the invention is to provide a device for initiating, synchronizing and optimizing the operation of individual equipment which uses no energy except when actually controlling the load.
A further object of the invention is to provide a means for controlled management of overall operation of groups of equipment at the same general location which effectively reduces demand by imposing synchronized optimum operation on individual equipment loads in the group.
A further object of the invention is to provide a means for controlled management of overall energy requirements of groups of equipment at the same general location, thereby reducing demand charges from a utility company supplying energy to the equipment.
Another object of the invention is to provide an apparatus for managing the overall energy requirements of electrical equipment which is adjustable in accordance with environmental conditions sensed by interacting condition sensing units.
Another object of the invention is to provide an apparatus for managing the overall energy requirements of a network of electrical equipment at diverse locations which is adjustable in accordance with a change in power line frequency signals initiated by the utility company.
A further object of the invention is to provide a means for synchronized staggered startup of individual loads on a network of electrical equipment at diverse locations in the event of a widespread power outage within the network.
Another object of the invention is to impose load demand and operation control on energy-consuming equipment so that all components of the equipment function individually but in concert during optimum periods of operation, without excessive run-on or premature cut-off, thereby extending equipment life and enhancing functional efficiency.
Finally, it is a general goal of the invention to provide improved elements and arrangements thereof in an apparatus for the purposes described which is inexpensive, dependable and fully effective in accomplishing its intended purposes.
These and other objects of the present invention will become readily apparent upon further review of the following specification and drawings.
The present invention meets or exceeds all the above objects and goals. Upon further study of the specification and appended claims, further objects and advantages of this invention will become apparent to those skilled in the art.
BRIEF DESCRIPTION OF THE DRAWINGS
Various other objects, features, and attendant advantages of the present invention will become more fully appreciated as the same becomes better understood when considered in conjunction with the accompanying Figure, and wherein:
The figure is a schematic diagram of the ensemble of an apparatus and its connections for carrying out the objectives of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The load demand control system of the present invention is generally comprised of the units enclosed within the dashed oval 99 labeled DEMAND CONTROL APPARATUS in the single drawing figure. With reference to the figure, power lines 10 pass through utility meter 12 at the structure where equipment 22 is located. Meter 12 measures usage and demand of electrical energy at that location. Operative main power line 10 is generally left unconditioned, and supplies operative power to equipment 22. Line 10 also powers a conditioning device 14, such as a transformer, thermostat, pressure limit switch, or the like, which in turn allows electrons to flow or sends a control signal to a control signal line 16. In a typical situation, control signal line 16 would transmit an AC voltage of 24 volts during the periods when a thermostatic control is, say, calling for cooling from an air conditioning unit. The control signal would normally activate switch 18 in main power line 10. Other internal equipment controls (not shown) may also effect the activation of other switches, such as 18, and the demand control device may also be interposed in those lines. For example, there may be a separate control signal line for operation of the ventilation fan of an air conditioner unit. However, for simplification purposes, a single demand control apparatus in a single control signal line of an individual piece of equipment will be described in detail in the following specification.
The demand control apparatus of the invention is interposed in control line 16. It is important to note that the entire demand control apparatus of this invention is connected to existing equipment only by interposition in a normal control signal (e.g. thermostat) line. No other connections are made. In the absence of the demand control apparatus, control power line 16 would open or close switch 18, thereby opening or closing the circuit of operative power line 10 and controlling the flow of operative power to load 20 within equipment 22. Again, it is noted that equipment 22 may include several individual loads 20, such as the compressor unit, control solenoids, several fans, etc. Only one load 20 is shown in equipment 22 for simplification, but the present invention can be used also with complex equipment having diverse multiple loads. The usual conventional electrical grounding means is not shown in the schematic diagrams as it is not a matter of concern in this invention.
The present invention includes digital recycle counter 24 and switch 26 shown in the dashed oval 99 labeled DEMAND CONTROL APPARATUS, as well as external conditioning device 36. It should be pointed out that external condition device 36 may be incorporated into the same physical unit as digital recycle counter 24 if desired. The external conditioning device is merely used to accept external signals in various forms, as they may be generated by various external sensors, and to convert those external signals to a form acceptable by digital recycle counter 24. Device 24 has been called a digital recycle counter because it: (1) counts the oscillations of a sinusoidally alternating input voltage in a digital manner; (2) causes switch 26 to open for a predetermined number of counts and then close for a predetermined number of counts; and (3) repeats or "recycles" the opening and closing pattern indefinitely as long as an input signal is present. All counting stops and the counter is dormant, consuming no energy, when there is no input signal delivered to line 16 by conditioning device 14 (e.g. thermostat 14). When an input control signal appears in line 16, after such a dormant period, the counting and off-on cycling of demand control switch 26 begins anew. For brevity, the phrase "digital recycle counter" has been shortened to "counter" at places in the ensuing description. It should be understood that the "counter" referred to herein refers to the special digital recycle counter as so far described and further amplified in the remaining description. Counter 24 is capable of reacting to other "external" signals in specific ways, as by altering the predetermined counts, more fully described later.
The demand control apparatus is interposed in control signal line 16 and is not directly connected to operative power line 10 and load 20. It is important to note the demand control apparatus of this invention is wholly within a control signal line at the point of control of the load. Input line 28 of counter 24 is tapped into the control signal line 16 at some point between equipment control signal conditioning device 14 and the equipment load control switch 18. Preferably, this connection is made as close to the load control switch as possible. Usually it is possible to make the connection within the physical confines of the equipment itself. In the specific example herein described, the connection could be made within the casing containing the compressor unit of a residential air conditioning unit.
It is important to emphasize that the demand control units of this invention are wholly connected in the control lines of individual subloads of the equipment. In other words, the air conditioner described may have a separate control line for the subloads of the compressor unit and the ventilation fan unit. A separate demand control apparatus could be used to control either one or both of these subloads. The overall power line to all the subloads of the air conditioning unit is generally not in any way altered by the demand control apparatus of this invention. In a typical installation the compressor unit may be cycled through the predetermined off-on periods while the ventilation fan motor is left running continuously throughout the entire time the thermostat is calling for cooling. It should be kept in mind that load 20 of the Figure may represent the total operative power consumed by a piece of equipment, such as an electric hot water heater, but, more generally, it represents an individual subload of a larger complex piece of equipment such as an air conditioner, heat pump, or refrigeration system.
In operation, counter 24 initially receives a flow of electrons over input line 28 from control signal line 16. Immediately, counter 24 begins counting the number of peaks in the AC input signal and sends an output signal over line 30 to open the normally closed switch 26. It will be obvious to the artisan that the count can be based on either the peaks or the zero crossings of the AC input signal as both may be easily accomplished with conventional circuitry. In either case, counter 24 totalizes the number of counts. During this first cycle, switch 26 is held open which, as seen by equipment control switch 18, is exactly the same as the state in which there is no signal in control signal line 16, which corresponds to the state in which conditioning device is satisfied, e.g., thermostat 14 is satisfied and not calling for cooling. For simplicity of description, this cycle is hereinafter referred to as the "off" cycle of the demand control apparatus.
In the interest of completeness, the first or "off" cycle of the demand controller with reference to an electric water heater load will be as described for comparison. A typical sequence of events follows:
(1) The water temperature drops below that called for by the water thermostat (conditioning device 14) within the equipment.
(2) The water thermostat (conditioning device 14) sends a control signal over control signal line 16 which would normally close equipment switch 18 and allow current to flow from main power line 10 to the heating coils of the equipment (load 20).
(3) The control signal is interrupted by the demand control apparatus which, immediately upon sensing the control signal in control signal line 16, through input line 28, commands counter 24 to open switch 26 and begin counting the oscillations in the "off" cycle.
As before in the air conditioner example, the state of equipment switch 18 remains exactly as it would have been in the absence of the control signal in control signal line 16, which corresponds to the state in which conditioning device is satisfied, e.g., thermostat 14 is satisfied and not calling for heating.
In both the above cooling and heating examples, it will be noted that the effect of the demand control apparatus thus far described is merely that of a delay switch. When cooling is called for, the onset of that cooling is delayed by the demand control apparatus; and when heating is called for, the onset of that heating is delayed by the demand control apparatus. However, the demand control apparatus does much more than act as a simple delay switch as will become evident from the remainder of this discussion.
Upon reaching a particular preset number of counts in the "off" cycle, counter 24 sends a signal over its output line 30 to close switch 26, thereby completing the normal circuit of control power line 16. In actual practice, the "signal" over output line 30 is really the absence of a signal which allows switch 26 to return to its normally closed position. In accordance with conventional terminology used in digital control technology, the absence of a voltage or a current in a line is often, as here, referred to as a signal. In this state, referred to as the "on" state, the demand control apparatus effectively steps out of the way and allows the conditioning device 14 to control the load as it normally would through equipment switch 18.
The "on" state triggers the separate counting and totalizing of the peaks in the AC input line 28. The "on" cycle of the demand control apparatus is maintained until the count total reaches a second preset number. The count during the on cycle can be interrupted in one of two ways. The first way is for the count to reach the second preset number allowed for in the "on" period of the equipment. In this case, the counter switches to the "off" cycle, opens switch 26, and begins a new count applied to the "off" cycle total. The second way is for the conditioning device or thermostat 14 to become satisfied at some time during the "on" cycle. In this case, the "satisfaction" signal from the thermostat causes the demand control device to stop counting anything and reset all totals to zero. Switch 26 is returned to its normally closed position in this state. In actual practice, the normal "satisfaction" signal from the thermostat corresponds to the absence of any signal in control signal line 16. Since there is normally no power present in the control signal line when the thermostat is satisfied, there is no power provided or consumed by the demand control apparatus during these periods. The fact that no power is consumed by the demand control apparatus during the periods when the equipment conditioning device is not sending a signal thus satisfies an important objective of the invention of not consuming unnecessary power in the process of controlling the use of power.
The digital recycle counter is designed so as to restart itself in a new "off" period counting cycle whenever interrupted power is again present in control signal line 16 to 28, i.e., whenever the thermostat again calls for cooling or heating. It is also important to note that control signal line 16 may be absent power because of normal switching at the thermostatic control device 14 or because of an overall power outage at the facility where the equipment is located. By restarting itself with a predetermined "off" period the demand control apparatus of the present invention also serves as an important synchronized network startup apparatus to assist utilities in getting back on line after emergency power outages. If a significant number of the power consuming devices on a network are controlled by the demand control apparatus of this invention, it is obvious that upon restoration of power to that network there will not be the characteristic startup surge of, say, thousands of motor loads. It is a well known fact that it takes more power to start and accelerate an electric motor than to maintain its rotation at a constant speed. If each individual motor load, as envisaged by this invention, is controlled by a demand controller, they will all be switched off line immediately when power returns to the lines. In addition, they will all be started at the individual count that has been preset for their individual "off" cycles. These preset "off" counts will not be the same for all motors on all the equipment. For example, one motor may be starting after, say, 3600 counts whereas another motor may come on line after, say, 5400 counts. Thus the startup transients from the first motor will have long disappeared before the startup transients of the second motor are introduced to the overall network. By appropriately staggering the "off" cycles of large energy consumption units on a network, the utility can be assured that startup transients will not be intolerable after a power outage. Likewise, individual users can prevent simultaneous startup transients from multiple units, as for example, in a large refrigeration plant having many units at a single locality.
With the apparatus of the present invention in the control signal line of an equipment, the "off" and "on" cycles, determined solely by counter 24, are imposed on the equipment during all periods when the normal equipment control (e.g. a thermostat) is calling for the equipment to be operated. The demand control device, in a sense, overrides the normal thermostatic controls of the equipment. However, the normal thermostatic controls must operate to activate the demand control device.
As an example, a space cooling unit might be under the overall control of a thermostat. When the thermostat first calls for cooling, the demand control device prevents operation of the cooling unit for an "off" period of typically about three minutes. Then, if the thermostat is still calling for cooling, the cooling unit is allowed to operate for an "on" cycle period which may be slightly longer, or about 4 minutes. If the thermostat is still calling for cooling after the 4 minutes of "on" operation of the cooling unit, the demand controller imposes another 3 minute "off" period on the cooling unit. Since the thermostat was not satisfied by the first 4 minute "on" period, it will probably still not be satisfied after the imposed 3 minute "off" period and another 4 minute "on" period will be allowed by the demand controller. Let us assume for the purposes of this example, that the thermostat is finally satisfied halfway through, or about 2 minutes into, the second "on" period. At this point, about 12 minutes (3 minutes off plus 4 minutes on plus 3 minutes off plus 2 minutes on) after the thermostat first called for cooling, the thermostat has been satisfied and the interior space is adequately cooled. During this 12 minute period the cooling unit has only actually operated for 6 minutes with a first 4 minute period followed by a rest of 3 minutes and a final 2 minute period. It has been found that the cooling accomplished by operating an air conditioning unit for 6 minutes in the pulsed nature just described, can approximate the cooling accomplished by operating the same unit for 6 continuous minutes as would be attempted by the equipment alone in the absence of the demand control apparatus.
In fact, it can be shown, both theoretically and by test data, that the cooling unit of the instant example cannot satisfy the thermostat in 6 continuous minutes of running. In an actual typical situation it would take about 10 minutes of continuous running of the cooling unit to achieve the same temperature in the same space as can be done in 6 minutes in the cyclic manner forced by the demand controller. Thus it is common for refrigeration and air conditioning equipment fitted with this invention to achieve increased efficiency. One reason for the increased efficiency is that a refrigeration compressor delivers more liquid freon to an evaporator coil (where the cooling occurs) when the process just begins, because there is no back pressure at the evaporator and because the evaporator is at a higher temperature after an "off" period. Another reason for the increased efficiency is the diminished formation of efficiency robbing ice at the evaporator coil, because of the warmup periods afforded by the imposed "off" periods. Ice formation is particularly deleterious to performance because it not only robs cooling capacity from the circulated air, but also it chokes the airflow and interferes with the circulation of that air over the evaporator coils.
It is important to note the apparatus of the present invention imposes its control on the load only through existing equipment load controls. Thus any special operation parameters of the equipment, such as freon pumpdown prior to compressor shutdown, are not interfered with by the addition of this load controller. Each counter is custom tailored to the specific needs, function, environment, and shortest effective window of operation for each load requirement of the equipment. "Optimum run operation" of one complete off/on cycle is determined for the load, based upon measurements and observations at the actual installation site. The counter is preset for that respective cycle of operation by setting the "off" and "on" cycles by means of DIP switches 32 on the face of counter 24.
Alternately, optical adjuster device 8, similar to infrared remotes on television sets, can be used to send signals to digital recycle counter 24.
AS previously described, the load is always off during the first preset number of totalized pulses, and a second preset number of totalized pulses governs the on time in which the load operates according to its own control parameters.
For another example, in the normal operation of refrigeration equipment, a compressor under its own thermostatic control may run for a long continuous period attempting to satisfy the equipment thermostat. Thus, frost may build up on the chilling coils which significantly reduces their chilling capacity. As previously discussed, air is cooled much more efficiently by passing it directly over very cold metal surfaces than it is by passing it over ice or frost layers on those metal surfaces. Electrical resistance heat is often employed in a defrost period. If during the defrost period, the temperature of the air being chilled rises above the reset or cutout thermostat setting, the defrost period is prematurely cut short and the compressor starts. The compressor once again runs continuously for an even longer period to satisfy the equipment thermostat control, thereby forming ice, so a longer defrost period is needed. This time the extended defrost cycle causes the air temperature to rise quickly above the reset or cutout thermostat setting, so the defrost period is prematurely cut again and the compressor overruns much too long. The cycle continues to build and worsen. This seemingly extreme example of inefficient operation is actually quite common. The relatively cheap cost of electrical energy has led many to tolerate such excesses. Refrigeration equipment operated in this manner is inefficient, wastes energy, and wears out rapidly.
Under control of the demand control apparatus of the present invention, a compressor has an optimum run or "on" time imposed upon it. This "on" time is determined at the time of installation of the apparatus and is dependent on local conditions. For example, if a small dwelling is equipped with a particularly massive cooling unit, a relatively short "on" time may be desirable. On the other hand, a longer "on" time might be needed if the particular cooling unit has a smaller capacity. In nearly all cases, however, the "on" time selected would be a time less than that necessary to satisfy the thermostat under continuous running. By preventing continuous run periods, efficiency is increased and frost buildup is inhibited.
The imposed "off" time of the optimum run operation cycle allows hot liquid freon from the condenser to transfer heat by conduction and convection to the coldest point at entrance to evaporator coils and further inhibit the formation of frost. The compressor would then be cycled on again, providing more chilling through frostless coils, thus gradually satisfying the thermostat with an optimum run operation cycle. This imposed control further reduces the defrost periods necessary because the formation of frost has been initially inhibited. The demand control apparatus has precluded overrun of the compressor of the refrigeration equipment while also satisfying the requirements of the equipment controls, and therefore the efficiency of the equipment is significantly enhanced. The refrigeration equipment could be cycled for longer on periods during off-peak hours, such as late evening/early morning hours, to build a reserve which could be used during peak periods, thereby allowing the counter to actuate the load for shorter "on" intervals during peak periods, further enhancing efficiency and controlling demand. This apparatus obtains unequaled results in the control and limit of diverse and individual load demand, since the load does not demand energy throughout the entire period of time which it normally would were it ungoverned by the demand control apparatus. Additionally, imposed control of the demand control apparatus prolongs component life and reduces the necessary maintenance and repair.
The digital recycle counter 24 employs DIP switches 32 for adjusting the various preset pulse count parameters once the off/on periods of the optimum run operation cycle of the load are determined. Switches 32 may be any suitable configuration for such task; for example, dual-in-package (DIP) switches. Two banks of switches 32 are used with one bank for setting the "off" count and the other for setting the "on" count. For the convenience of the installer, switches 32 may have indicator indicia approximated by real time, but this is not really necessary. The indicator indicia may also represent the totalized pulses. Alternately, optical devices can be used to perform the adjustment function from a remote location.
The counter does not employ any real time or any timing device in determining the onset or termination of the optimum run operation cycle off/on intervals. Rather, it counts the number of pulses in the frequency of the signal in control signal line 16, so the power line pulsations are only related to time insofar as the frequency is a predetermined constant. Contrary to popular belief, the frequency of a typical power line is not a constant 60 Hertz and therefore 60 counts does not necessarily correspond to an exact time period of 1 second. In fact, the only time counter 24 is active is when a control signal is sent through control signal line 16 from the equipment controls 14 to actuate existing load relay switch 18. In other words, if no equipment control signal is sent to control signal line 16 to actuate switch 18 and energize load 20, counter 24 is dormant and draws no energy. The dormant counter makes no counts, keeps no "time", and consumes no energy during these periods. Thus, counter 24 not only controls the load demand and operation, but also conforms to that objective by not requiring a continuous power supply to function.
Based solely upon the totalized number of pulses, counter 24 determines, from the preset parameters of the optimum run cycle of operation, when to actuate switch 26. Switch 26 opens or closes accordingly, completing or breaking the circuit of control signal line 16 to switch 18. If switch 26 is closed, which it normally is until acted upon by counter 24, the circuit is complete and control power line 16 actuates switch 18 in accordance with the normal desires of the equipment itself. If switch 26 opens and breaks the circuit of control signal line 16, equipment relay switch 18 cannot be closed and no operative power can be supplied to the load through operative power line 10. It is thus seen that counter 24 imposes a precisely controlled optimum run operation on load 20.
Since both utility meter 12 and counter 24 are AC line synchronized, the imposed control from counter 24 keeps the off/on optimum run cycle of the equipment "in sync" with the meter. If there is an interruption of power, such as an outage, counter 24 and meter 12 naturally both lose power. Upon resumption of power, the preset totalized pulse intervals in counter 24 do not resume where they had been interrupted, but rather, a new off/on optimum run cycle of operation for the controlled load is begun. While meter 12 may start a new demand metering interval, this is not a necessary consideration of counter 24, as is required by many other methods and systems. The very fact that the load is cycled off during a portion of the metered interval, where it would normally be on, is enough to reduce demand and thereby reduce demand charges from the utility company. Since the load is functioning in a maximum efficient window of operation, it will be controlled by counter 24 to cycle "on" a great deal less than it would if it were operating under its own equipment controls, thereby significantly limiting demand. Further, the fact that the load is controlled in its operation allows for additional loads to be added to a supposedly maximum load capacity, with no malfunction of equipment and no overload.
Also, upon resumption of power after an interruption or outage, load 20 will not be energized instantly since it is controlled by counter 24, which starts a new off/on optimum run cycle, the first interval being the off interval. There is no need to have a time delay, no need for adjustment to the controls of the load, and no need to turn equipment off manually. It is also insured that upon resumption of power, there are no simultaneous transient high start up currents imposed upon the circuits connecting the individual loads at a given location. Note that if the "off" counts of the various controlled equipment are set slightly differently, they will be automatically staggered when they come back on line. Equipment at various locations on the entire electrical network, as seen from the electrical generation facility, can be similarly staggered for trouble-free startup after a power outage. There is no load demand surge created, since no controlled load is energized at the moment of power resumption, nor are any two loads energized at the same time after the cessation of the first off intervals of the respective counters. Each load is individually controlled by its own process apparatus, which is customized to allow an individual "off" count and an individual "on" count for its respective load, so different loads would automatically be energized at different counts.
The actual "off" counts chosen for various equipment at a given location, or for groups of subscribers on a network, are the subject matter of study and development which must be done in cooperation with the individual utility companies. The actual schemes developed from these studies may become the subject matter of future patents. The point here is that the optimizer of this invention provides an ideal mechanism for implementing such schemes.
Particularly important is the fact that after an outage, if switches 32 have been adjusted to, for example, an indication of "one minute" (equal to 3600 pulses) for a first totalized pulse "off" interval for load 20, and the utility company can only generate a frequency of 58 Hertz or 3480 pulses during the first real time minute after power resumption, counter 24 will not cycle into a first totalized pulse "on" interval for load 20 until 120 counts past that one minute of real time, or approximately 62.07 seconds, since it does not actually operate on the basis of the time increment indicia inscribed beside switches 32. The counter recognizes only a precise point (such as a positive peak, a negative peak, or a zero crossing) of an oscillation in the control signal line 16 and totalizes a sufficient number of those precise points of the pulses to match the preset interval, even if the real time exceeds or falls short of the indicated interval.
As a further example, the first interval of "off" time for a load may be indicated as two minutes according to the indicia on the face of the counter next to the dip switches. In reality the setting is not two minutes, but rather 7200 totalized oscillation counts. If the utility company exceeds or falls short of 7200 oscillations in two minutes, the indicated "two minutes" of time set on DIP switches 32 does not correspond with two minutes of real time and the counter will not operate to change any cycle in precisely two minutes of real time. If only 6600 oscillations are generated during the first two minutes of real time (55 Hertz), counter 24 will count 600 pulses further before operating control signal line switch 26. If 7200 oscillations are generated during only one and three-quarter minutes of real time, DIP switches 32 may be set with an indication of "two minutes", but counter 24 actuates control signal line 26 after only one and three-quarter minutes real time, according to the totalized pulses. The totalized oscillation counts are the sole criteria by which counter 24 will actuate switch 26.
Therefore, load 20 is always synchronized with the power supplied to it, and has a precise control of its load demand imposed upon it by rigid enforcement of its optimum run cycle of operation.
Counter 24 also makes provision for adjustment to an "alternate" off/on optimum run cycle of operation based upon a contingency for such adjustment from external information. The general input location for external conditions is indicated schematically in FIG. 1 by external condition device 36. It should be understood the external condition device could be built into the counter 24. Generally, external sensors send information to device 36, and that external information is processed by device 36 so as to signal counter 24 when to switch to an alternate run cycle.
The "alternate" run cycles consist of additional preset "off" or "on" intervals allowing extension of the run cycle periods during exceptional circumstances. These additional "off" periods and "on" periods are completely independent of the periods discussed up until now, and they are used for fine tuning the periods to achieve an alternate optimum run cycle of operation to further enhance load efficiency. In practice, the alternate run periods are simply additional counts added to the normal counts of the "on" cycle and/or additional counts added to normal counts of the "off" cycle. The counts for these additional "off" and "on" periods are each preset and controlled by an independent set of DIP switches on the counter face at 32 and are referred to hereafter as the "extend" periods. Alternately, optical means can be used to perform the same function.
If the equipment being controlled is a heat pump and resistance heat, each would have its own counter set to an optimum run cycle of operation which would also complement the operation of the other; the heat pump would operate when the resistance heating unit was off, and vice versa.
In the case of resistance heating, the counters would receive input from an external sensor, such as a temperature sensor, located outside the structure in which the equipment is housed. When the outside temperature goes above a preset limit of external condition device 36, it would signal the counters so that the resistance heat would be cycled "off" for the normal off interval plus the preset "off extend" interval. In other words, if heating is being delivered and it becomes warm outside, less heat will be delivered.
Further in the case of resistance heating, if the external sensor indicated a temperature below a critical preset limit in device 36, it would signal the counters to increase the overall resistance heat "on" interval by adding the "on extend" interval to the normal "on" interval. In other words, if heating is being delivered and it becomes very cold outside, more heat will be delivered.
In the case of heat pump cooling, the counters would also receive input from an external sensor, such as a temperature sensor, located outside the structure in which the equipment is housed. When the outside temperature goes above a different preset critical limit (set in external condition device 36), it would signal the counters so that the heat pump cooling compressor would be cycled "on" for the normal on interval plus the preset "on extend" interval. In other words, if cooling is being delivered and it becomes warm outside, more cooling will be delivered.
Further in the case of heat pump cooling, if the external sensor indicated a temperature below a critical preset limit in device 36, it would signal the counters to decrease the overall cooling by extending the "off" period of the heat pump compressor by adding the "off extend" interval to the normal "off" interval. In other words, if cooling is being delivered and it becomes cold outside, less cooling will be delivered.
Thus, an "alternate" optimum run cycle of operation is imposed by external sensors on the counters to gain enhanced efficient use of temperature conditioning equipment such as a heat pump and resistance heat.
No other process, system or device known imposes such a precise and efficient load demand and operation cycle for the load it controls within easy operating parameters of the equipment.
Since the counter operates by totalizing the count of pulses of the frequency of the power, the operation of the unit is precise in its synchronization with the power supplied to it. Since precise control is imposed upon the load to limit it to an optimum run off/on operation cycle during any demand metering interval, the demand of the load or loads of the equipment is greatly reduced. More importantly, all such controlled equipment is in precise synchronization with the power supplied, so that a reduced overall electrical demand on the generating equipment is present at any given time. If the utility company has a problem with a particular plant and must take it off-line, any interruption in the oscillations in the power line during the change-over will automatically turn off controlled loads in the respective power lines in which the interruption occurs. In fact, the utility company itself can control load demand simply by momentarily interrupting supply power flow lines to restart the preset "off" intervals and automatically turn off the respective controlled loads along given lines or over the entire service area.
It is recognized, however, that turning off the power to an entire grid of users, even momentarily, can lead to many unwanted side effects. For example, the electrical power supplied to a computer must be constantly supplied during operation. A momentary lapse of power to a computer can cause complete loss of all random access memory and consequent loss of control and valuable data. As another example, momentary loss of power to most digital clocks will require them to be manually reset. Therefore it is imperative that power lapses be minimized, and it is recognized that the above mentioned momentary blackout counter resetting mechanism is not practical.
The remainder of this specification will describe an aspect of the demand control apparatus of this invention that is, indeed, very practical for use in demand shedding, and well within the realm of current technology. The invention, thus far described, has essentially been described in my earlier applications referred to in the first section of this specification. The previous description has followed the pattern of those earlier applications with some minor amplification and changes made for the sake of clarity. The following description, on the other hand, presents new concepts, heretofore unknown.
Note that external condition device 36 of FIG. 1 is shown with an input tap from the control signal line 16. How can the control signal line be a source of an external input? The answer is that the line current oscillates with an alternating current whose frequency is controllable from an external source. It is well known to even the general public that the standard frequency of the power lines in the United States is 60 Hertz (cycles per second). The standard frequency in many European countries is 50 Hertz. In the old days the frequency of the electrical power depended solely upon the rotation speed of the electromagnetic dynamo used to generate the power. If the dynamo slowed down the frequency of the power would be low, and if it speeded up the frequency would be high. This is no longer true. Modern electrical power generation plants have the capability to precisely control the frequency of the power they generate and provide over their lines. As a matter of fact, the line frequency can be easily controlled to a precision of 0.01 Hertz or one one-hundredth of a cycle per second. This precise frequency control is in fact used by the utilities for various purposes today, but not for the purpose envisioned here. It is known, for example, that some utilities run on a frequency of 59.99 Hertz during the day and a frequency of 60.01 Hertz during the evening to make up for the lost time on subscribers electrical clocks. The purpose here is not to fully describe how or why the utilities control the line frequency, but rather merely to indicate that such line frequency control is conventional and is being routinely accomplished at the present time.
For purposes of the instant invention, external condition device 36 may be equipped with a line frequency sensing circuit which, upon sensing a predetermined frequency in control signal line, will signal the counter to switch to the "extend" mode described above. The details of such circuitry are conventional and not further described herein. Such a line frequency sensitive counting device is commercially available from S.S.A.C. of Baldwinsville, N.Y., and may be ordered as part number FDD24A-3324.
For purposes of simplicity, the frequency sensitive digital recycle counter operation will be exemplified here only in one of its simplest applications. Let us suppose that it is a very hot day and the air conditioning demand for a given area is at a very high level with the generating plant being stretched to the limits of its capacity.
Present day options for the utilities are very limited. The voltage may be reduced by perhaps 10% going into what is known as a "brown out" phase. Power may be transferred from neighboring utility companies but they may not have extra available. As a last resort, power supplied to certain non-essential users may be interrupted. Finally, after all else fails, the various utilities involved are forced to go into a massive "rolling blackout" in which large areas of the country are completely without power at the time they need it the most. The economic and social consequences can be serious and even disastrous. Such rolling blackouts have already occurred along the east coast of the United States.
Let us explore the same critical situation assuming that the air conditioning and refrigeration loads have been equipped with the instant invention. The preset critical line frequency of the frequency sensing units in the optimizer counters will be assumed to have been set at 59.9 Hertz. When the line frequency drops to 59.9 Hertz, the frequency sensors will send an extend signal to the counters of all controlled units so as to increase the "off" cycle by adding to it the preset "off extend" cycle previously described. With every air conditioning unit being imposed an additional off period, the overall load seen by the utility will be dramatically reduced and fewer users will suffer brown outs or black outs. In addition, the slightly reduced cooling capacity at individual locations will be a slight inconvenience to some and probably not even noticed by most.
Thus, when the utility company gets into demand trouble all that need be done is to reduce the line frequency by a mere 0.1 Hertz| This is the ultimate in demand control from the standpoint of the utility. It requires no capital investment in equipment because the line frequency controllers are already in place. From the standpoint of the consumer, installation of the devices on his equipment is relatively inexpensive and the savings in energy bills will pay for the optimizing equipment in less than a year in almost all cases.
It is contemplated that a much more sophisticated line frequency signal scheme could be developed to send all kinds of communication signals to receiving equipment. For example, different critical line frequency values could be used to shed load from different classes of subscribers. Load from industrial users could be cut back at, say, 59.9 Hertz while load from residential users could be cut back at 59.8 Hertz. As another example, a signal of one frequency for a certain period of time followed by another frequency for another period of time could signal some equipment to increase their "off" cycle and other equipment to decrease their "on" cycle. Both types of cycle changes would reduce the overall demand on the utility. The permutations and combinations of communications possible by controlling power line frequency is endless. The various possibilities will be the subject matter of future patent applications. This is the purest demand control and management possible at this time.
The present invention is far superior to any other method or system known. The apparatus is also very inexpensive and easy to install. It requires no alteration of the existing equipment or its working components. It does not preclude the controls of the device itself, but rather complements them, imposing optimum efficient operation well within the operating parameters of the equipment to satisfy the equipment controls. It needs no other component to control and manage year-round demand and operation of a load, and in fact draws no energy when not activated by the control signal line from the equipment controls.
Therefore, the embodiments described in the present application are not to be taken as a limiting disclosure, since endless variations and applications of the present apparatus are envisioned. | A demand control apparatus includes a switch in the control signal line of an electrically powered piece of equipment. The switch is controlled by a digital recycle counter so as to periodically cycle off and on during times when an equipment generated control signal is present in the control signal line. The control signal line could be a thermostat control line on a standard air conditioning unit and the equipment generated control signal would normally correspond to the thermostat calling for cooling. When the switch is opened the equipment reacts as though the thermostat has been satisfied. When the equipment generated AC control signal is sensed in the control signal line, a digital counter is activated to hold the switch open until a preset number of AC pulses have occurred. The switch is then closed until a second preset number of AC pulses have occurred. The open-closed cycle is repeated as long as the equipment control signal is present. The cycle periods can be adjusted in response to external conditions such as ambient temperature or line frequency. In multiple applications, load diversity is improved and aggregate demand is reduced after power outages. Sequential start of diverse and multiple loads is assured. | 8 |
This application is a divisional of Ser. No. 07/464,121, filed Jan. 12, 1990 now U.S. Pat. No. 5,117,044.
FIELD OF THE INVENTION
The present invention relates to a polymerizable compound which has both an alpha-ketoester group and a polymerizable double bond, and a polymer prepared therefrom.
BACKGROUND OF THE INVENTION
It has been known that an alpha-ketoester group ##STR2## is a chemically active group which can be ester-exchanged with an active hydrogen containing-compound, such as an alcohol or an amine, or can be easily hydrolyzed.
If the alpha-ketoester group is introduced into a polymer, the polymer would be chemically interesting. In order to obtain such polymers, a compound which has both an alpha-ketoester group and a polymerizable double bond is required.
EP 20,000 Bl and NL 6612666 disclose number of a compounds which have both an alpha-ketoester group and a polymerizable double bond in the form of general formula, but actually synthetic examples are very few.
SUMMARY OF THE INVENTION
The present invention provides a novel compound which has both an alpha-ketoester group and a polymerizable double bond. The compound has the formula (I);
A--X--COCOOR.sub.1 (I)
wherein
A represents a C 1 -C 18 alkenyl, alkynyl, alkenylaryl or alkenylaralkyl group, or a group represented by: ##STR3## wherein R 2 and R 3 , which is the same or different, represents a hydrogen atom, or a C 1 -C 5 alkyl group,
Y represents an oxygen atom or --NR 4 --, in which R 4 represents a hydrogen atom or a C 1 -C 5 alkyl group, n is an integer of 1 to 5, m is an integer of 1 to 10 and l is 0 or an integer of 1 to 20;
R 1 represents a hydrogen atom, a C 1 -C 5 alkyl group or an aryl group; and
X represents an oxygen atom, a sulfur atom, --COO-- or --NR 5 --, in which R 5 is a hydrogen atom or a C 1 -C 5 alkyl group, provided that if the compound contains a Y group, X is not --NR 5 --.
The present invention also provides a production of the above compound and polymers prepared therefrom.
The present invention further provides a curable composition which contains the polymer obtained from the above compound.
DETAILED DESCRIPTION OF THE INVENTION
The polymerizable compound of the present invention can be prepared by reacting an active hydrogen-containing compound represented the formula;
A--XH (II)
[wherein A and X are the same as defined above.] with an ester compound represented by the formula;
Z--COCOOR.sub.1 (III)
[wherein R 1 is the same as defined above and Z represents a halogen atom or --OR 1 --.]
The active hydrogen-containing compound (II) is a compound which has a hydrogen atom directly bonded to an electrophilic atom or group (e.g. oxygen, sulfur, --NR 4 -- or --COO--). Accordingly, the active hydrogen may be present in a hydroxyl group, a thiol group, an amino group or a carboxyl group. The group A in the active hydrogen-containing compound (II) is a group which imparts polymerizability to the compound, and includes a C 1 -C 18 alkenyl group, such as propenyl, isopropenyl, butenyl, allyl etc.; a C 1 -C 18 alkynyl, such as propynyl, butynyl etc.; a C 1 -C 18 alkenylaryl group, such as vinylphenyl, propenylphenyl etc.; a C 1 -C 18 alkenylaralkyl group, such as vinylphenylethyl, vinylphenylpropyl etc.; and a group represented by ##STR4## wherein R 2 and R 3 , which is the same or different, represents a hydrogen atom, or a C 1 -C 5 alkyl group, Y represents an oxygen atom or --NR 4 --, in which R 4 represents a hydrogen atom or a C 1 -C 5 alkyl group, n is an integer of 1 to 5, m is an integer of 1 to 10 and l is 0 or an integer of 1 to 20. Typical examples of the active hydrogen-containing compounds are acrylic acid, methacrylic acid, 2-hydroxyethyl methacrylate, allylamine, 2-hydroxyethyl acrylate, propargyl alcohol, 2-hydroxypropyl methacrylate, p-aminostyrene, 2-hydoxypropyl acrylate, p-hydroxyethylstyrene, allylamine, propargylamine, 2-(2-hydroxyethoxy)-ethyl acrylate, 2-hydroxy-3-(2-propenyloxy)-propylacrylate, ##STR5## and the like.
The ester compound (III) employed in the present invention includes oxalic diesters, such as dimethyl oxalate, diethyl oxalate, diisopropyl oxalate, dibutyl oxalate, diphenyl oxalate etc.; alkoxalyl halides, such as methoxalyl chloride, ethoxalyl chloride, etc.
If the ester compound (III) is the alkoxalyl halide (Z is halogen), the reaction between the compound (III) and the compound (II) is a dehydrohalogenation reaction which quantitatively progresses. The reaction may be carried out at room temperature to 150° C., preferably 50° to 100° C. in an inert solvent. Examples of the inert solvents are aliphatic hydrocarbons, such as pentane, hexane and heptane; aromatic hydrocarbons, such as benzene, toluene and xylene; cycloaliphatic hydrocarbons, such as cyclohexane, methylcyclohexane and decalin; petroleum hydrocarbons, such as petroleum ether and petroleum benzine; halogenated hydrocarbons, such as carbon tetrachloride, chloroform, 1,2-dichloroethane; ethers, such as ethyl ether, isopropyl ether, anisole, dioxane and tetrahydrofuran; ketones, such as acetone, methyl ethyl ketone, cyclohexanone, acetophenone and isophorone; esters, such as ethyl acetate, butyl acetate, propyleneglycol monoethyl ether acetate and ethyleneglycol monoethyl ether acetate; acetonitrile; dimethylformamide; dimethylsulfonide; and the like. Removal of the byproduct hydrogen chloride may be carried out by a method wherein nitrogen gas is blown into the reaction vessel, or a method wherein hydrogen chloride is reacted with a tertiary amine to form a salt of HCl which is removed out.
If the compound (III) is the oxalic diester (Z is--OR 1 ), the reaction between the compound (III) and the compound (II) is an ester exchange reaction which is generally carried out using excess dialkyl oxalate in the presence of a catalyst and a polymerization inhibitor. The amount of the dialkyl oxalate is 2 to 20 times, preferably 3 to 8 times larger than the molar amount of the compound (II) and the reaction temperature is within the range of room temperature to 150° C., preferably 50° to 120° C. The reaction may be carried out in an inert solvent as mentioned above. Typical examples of the catalysts are tin compounds, such as dibutyltin dilaurate, dibutyltin oxide and monobutyltin triheptate; mixture catalysts, such as dimethyltin diiodide and tetraphenylantimony iodide, dimethyltin diiodide and hexamethyl phosphoric triamide; acidic compounds, such as p-toluenesulfonic acid, dodecylbenzenesulfonic acid, sulfuric acid, chloric acid, nitric acid and boron trichloride etherate; basic compounds, such as triethylamine, 1,4-diazabicyclo[2,2,2]octane, 1,8-diazobicyclo[5,4,0]undecene-7, pyridine sodium methoxide, sodium ethoxide and t-butoxypotassium hexamethylphosphoric triamide; metal oxides or metal salts, such as manganese acetate, cobalt acetate, calcium acetate, lithium acetate, zinc acetate, magnesium acetate, antimony trioxide, lead dioxide, ferric chloride, aluminum triisopropoxide and tetraisopropoxy titanium; and the like. Typical examples of the polymerization inhibitors are hydroquinone, p-methoxyphenol, 2,6-di-t-butyl-4-methylphenol, 4-t-butylcatechol, bisdihydroxybenzylbenzene, 2,2'-methylenebis(6-t-butyl-3-methylphenol), 4,4'-thiobis(6-t-3-methylphenol), p-nitrosophenol, diisopropylxanthogen sulfide, N-nitrosophenylhydroxylamine ammonium salt, dithiobenzylsulfide, p,p'-ditolyltrisulfide, p,p'-ditolyltetrasulfide, dibenzyltetrasulfide, tetraethylthiuramsulfide and the like.
The obtained product may be purified by distillation, crystallization, chromatography etc. Distillation is generally effected at a reduced pressure (from atmospheric pressure to 0.01 mmHg) at a temperature of room temperature to 180° C., preferably 50° to 120° C. in the presence of zeolite or with stirring.
The obtained polymerizable compound of the present invention can be polymerized solely or with a copolymerizable compound. Polymerization may be carried out at a temperature of 50° to 150° C., preferably 70° to 120° C., in the inert solvent mentioned above in the presence of a polymerization initiator. Typical examples of the polymerization initiators are azobisisobutylonitrile, benzoyl peroxide, cumene hydroperoxide, tetramethyltiuramdisulfide, 2,2-azobis(4-methoxy-2,4-dimethylvaleronitrile), acetylcyclohexylsulfonyl peroxide, 2,2'-azobis(2,4-dimethylvaleronitrile) and the like.
The copolymerizable compound employed in the present invention includes mono-olefins or di-olefins, such as styrene, alpha-methylstyrene, alpha-ethylstyrene, 2'-methyl-1-butene, ethylene, propylene, butylene, amylene, hexylene, butadiene-1,3, isoprene etc.; halogenated mono-olefins or di-olefins, such as alpha-chlorostyrene, alpha-buromostyrene etc.; organic or inorganic esters, such as vinyl acetate, vinyl propionate, vinyl butylate, vinyl banzoate, methyl methacrylate, ethyl methacrylate, propyl methacrylate, hexyl methacrylate, methyl acrylate, ethyl acrylate, propyl acrylate, allyl chloride, allylcyanamide, allyl acetate, allyl propionate, allyl butylate, dimethyl maleate, diethyl maleate, dimethyl fumarate, diethyl fumarate, dimethacryl fumarate, diethyl glutarate etc.; organic nitriles, such as acrylonitrile, methacrylonitrile, ethacrylonitrile, 3-octenenitrile, crotonitrile and oleonitrile; unsaturated acids, such as acrylic acid, methacrylic acid, crotonic acid etc.; unsaturated alcohols, such as a monoester of the unsaturated acid mentioned above and a glycol (e.g. ethylene glycol or propylene glycol); unsaturated amides, such as acrylamide, methacrylamide, crotonamide etc.; unsaturated sulfonic acids or salts thereof, such as 2-sulfoethyl acrylate, p-vinylbenzenesulfonic acid etc.
The polymer (or copolymer) of the present invention has at least two alpha-ketoester groups which are reactive with other active hydrogen-containing groups, particularly a hydroxyl group. Accordingly, the polymer may be combined with a compound having at least two hydroxyl groups, i.e. polyhydroxyl compound, to form a curable composition. The curable composition has excellent properties in low temperature curing ability and acid resistance. The polyhydroxyl compound includes polyhydric alcohols, polyester polyols, polyether polyols, polyurethane polyols, polyvinyl alcohols, phenol resins, hydroxyl-containing polybutadine, hydroxyl-containing polychloroprene, ring-opened epoxy resins, polyorganosiloxane polyol and the like.
Typical examples of the polyhydric alcohols are 3-allyloxy-1,2-propane diol, 2,2-bis(chloromethyl)-1,3-propane diol, 2-bromo-2-nitro-1,3-propane diol, 3-bromo-1,2-propane diol, butane diol, butyne diol, cyclohexane diol, cyclooctane diol, cyclopentane diol, decalin diol, decane diol, ethylene glycol, propylene glycol, dihydroxyacetophenone, dihydroxyanthraquinone, dihydroxybenzophenone, hydroxybenzylalcohol, catechol, pentaerythritol, glycerol, amylose, lactose, sucrose, manitol, maltose and the like.
The acryl polyol is a polymer of a hydroxyl containing ethylenically unsaturated monomer. Examples of the hydroxyl containing unsaturated monomers are 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate and the like. The acryl polyol may be a copolymer of the above mentioned monomers with other monomers. Examples of the other monomers are methyl (meth)acrylate, ethyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, ethylhexyl (meth)acrylate, alpha-methylstyrene, vinyltoluene, t-butylstyrene, ethylene, propylene, vinyl acetate, vinyl propionate, acrylonitrile, methacrylonitrile, dimethylaminoethyl (meth)acrylate, and the like.
Typical examples of the polyester polyols are a condensate of a polyhydric alcohol as mentioned above and a polybasic acid or an anhydride thereof (e.g. phthalic acid, tetrahydrophthalic acid, tetrachlorophthalic acid, hexahydrophthalic acid, succinic acid, maleic acid, fumaric acid, adipic acid, sebacic acid, trimellitic acid, pyromellitic acid etc.); a reaction product of a polyhydric alcohol as mentioned above with an epoxy compound (e.g. n-butyl glycidyl ether, allyl glycidyl ether, Cardura E available from Yuka Shell Company etc.); an alkyd polyol (a product of a polyhydric alcohol and oil (e.g. soybean oil and safflower oil)); a ring open product of ε-caprolantone; and the like.
Examples of the polyether polyols are an adduct of a polyhydric alcohol as mentioned above and an alkylene oxide (e.g. ethylene oxide, propylene oxide, tetrahydrofuran etch) and the like.
The polyurethane polyol may be prepared by reacting a polyol as mentioned above and a polyisocyanate compound. Examples of the polyisocyanate compounds are ethylene diisocyanate, propylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate, 1-methyl-2,4-diisocyanatocyclohexane, 1-methyl-2,6-diisocyanatocyclohexane, diisocyanatodimethylxylene, diisocyanatodiethylxylene, lysine diisocyanate, 4,4'-methylenebis(cyclohexylisocyanate), 4,4'-ethylenebis(cyclohexylisocyanate), alpha, alpha'-diisocyanato-1,3-dimethylbenzene, alpha, alpha'-diisocyanato-1,4-dimethylbenzene, isophorone diisocyanate, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 1,5-naphthylene diisocyanate, 4,4'-methylenebis(phenyleneisocyanate), triphenylmethane triisocyanate and a polymer thereof. The polyol for the polyurethane polyol may be polymeric polyol, such as polyether polyol or polyester polyol.
Examples of the phenol resins are novolac or resol type phenol resin, rosin modified phenol resin, alkylphenol resin, butylated resol resin, allyl ether resol resin and the like.
The polyorganosiloxane polyol includes a polymer or cyclic compound having both alkylhydroxyalkylsiloxy unit and dialkylsiloxy unit or (and) diphenylsiloxy unit, α,ω-bis(hydroxyalkyl)polydimethylsiloxane and the like. Typical examples of the polyols are ##STR6##
The curable composition of the present invention may generally contain a catalyst as mentioned in the synthesis of the polymerizable compound. The catalyst may be present in the composition in an amount of 0.0001 to 10% by weight, preferably 0.001 to 5% by weight based on the total amount of the poly(alpha-ketoester) and the polyhydroxyl compound.
The curable composition may contain a solvent if necessary. The solvent can be the inert solvent as mentioned above, but alcohols (e.g. ethylene glycol, 2-ethylhexanol, t-butanol, n-hexanol, n-butanol, cyclohexanol, isopropanol, n-propanol, benzyl alcohol, ethanol, methanol etc.) may be employed. The solvent may be present in the composition in an amount of 0.01 to 90% by weight, preferably 0.5 to 80% by weight, but alcohols are preferably 50% by weight or less because they are ester-exchanged with alkoxalyl ester.
The curable composition may be cured at a temperature of 70° to 200° C., preferably 90° to 180° C. for 5 minutes to 2 hours, preferably 10 minutes to one hour.
The polymerizable compound and polymer of the present invention have the alpha-ketoester group which can be ester-exchanged with an active hydrogen containing-compound, such as an alcohol or an amine, or can be easily hydrolyzed. The polymer may be suitable for coating, adhesive, plastics, fiber and the like. The polymer may be combined with another active hydrogen containing compound to form a curable composition. The composition is suitable for the field of coating or adhesive.
EXAMPLES
The present invention is illustrated by the following Examples which, however, are not to be construed as limiting the present invention to their details.
EXAMPLE 1
A solution of 5.80 g (0.1 mol) of allyl alcohol and 150 ml of benzene was mixed with 10.1 g (0.1 mol) of triethylamine, and cooled to 8° C. A solution of 13.65 g (0.1 mol) of ethoxalyl chloride and 100 ml of benzene was added dropwise for 40 minutes. The formed triethylamine hydrochloric salt was filtered at a reduced pressure and rinsed with 50 ml of benzene. The filtrate was condensed at a reduced pressure to obtain brown liquid which was Kugelrohr distilled to obtain transparent liquid of allylethyl oxalate. It had a boiling point of 93° to 95° C./0.25 Torr (using Glass Tube Oven availabel from Shibata Kagaku Co., Ltd.) and a viscosity of 30 cp (using EL type viscometer available from Tokyo Keiki Co., Ltd. at 25° C.).
EXAMPLES 2 to 8
Synthesis was conducted as generally described in Example 1, with the exception that reactants and conditions were those shown in Table 1. The viscosity or melting point of the obtained compound is shown in Table 1.
TABLE 1__________________________________________________________________________Example Kugel-roll Viscosity.sup.1 orNo. Compound (II) Compound (III) boiling point melting point (°C.)__________________________________________________________________________2 Propargyl alcohol Ethoxalyl chloride 168-166° C./0.3 Torr 100 cp3 Methacrylic acid Ethoxalyl chloride 122-124° C./0.3-0.2 Torr 57 cp4 2-Hydroxyethyl Ethoxalyl chloride 124° C./0.4 Torr 200 cp5 2-Hydroxyethyl Ethoxalyl chloride -- 250 cp6 Allylamine Ethoxalyl chloride 133-124° C./0.3 Torr --7 Propargylamine Ethoxalyl chloride 152-153° C./0.5-0.6 Torr 61-63° C.8 FM-2.sup.2 Ethoxalyl chloride -- 77 cp__________________________________________________________________________ .sup.1 Measured at 25° C. .sup.2 CH.sub.2 ═C(CH.sub.3)--COO--CH.sub.2 CH.sub.2 --O(CO--(CH.sub.2).sub.5 O).sub.2 H available from Daicel Chemical Industries Co., Ltd.
EXAMPLE 9
Three grams of p-toluenesulfonic acid and 58.0 g (1 mol) of allyl alcohol were mixed with 438 g (3 mol) of diethyl oxalate and mixed at 90° C. for 5 hours with distilling ethanol. It was cooled and then distilled at a reduced pressure to obtain allylethyl oxalate.
EXAMPLE 10
Ethylpropargyl oxalate was obtained as generally described in Example 9, with the exception that 50 g (1 mol) of propargyl alcohol, 438 g (3 mol) of diethyl oxalate and 3 g of p-toluenesulfonic acid were employed.
EXAMPLE 11
Ethylmethacryloyl oxalate was obtained as generally described in Example 9, with the exception that 86 g (1 mol) of methacrylic acid, 438 g (3 mol) of diethyl oxalate and 3 g of p-toluenesulfonic acid were employed.
EXAMPLE 12
2-Ethoxalyloxyethyl methacrylate was obtained as generally described in Example 9, with the exception that 130 g (1 mol) of 2-hydroxyethyl methacrylate, 438 g (3 mol) of diethyl oxalate and 3 g of p-toluenesulfonic acid were employed.
EXAMPLE 13
2-Ethoxalyloxyethyl acrylate was obtained as generally described in Example 9, with the exception that 116 g (1 mol) of 2-hydroxyethyl acrylate, 438 g (3 mol) of diethyl oxalate and 3 g of p-toluenesulfonic acid were employed.
EXAMPLE 14
A solution of 57.0 g (1 mol) of allylamine and 200 ml of tetrahydrofuran was added dropwise to 146 g (1 mol) of diethyl oxalate with cooling by water. After the completion of the addition, the reaction mixture was condensed at a reduced pressure and then distilled under vacuum to obtain N-allylethyl oxalate.
EXAMPLE 15
N-Propargylethyl oxalate was obtained as generally described in Example 14, with the exception that 56 g (1 mol) of propargylamine and 146 g (1 mol) of diethyl oxalate were employed.
EXAMPLE 16
A 500 ml flask equipped with a decanter, a thermometer, a stirrer and an inlet for nitrogen gas was charged with 65.1 g (0.5 mol) of 2-hydroxyethyl methacrylate and 365.4 g (2.5 mol) of diethyl oxalate, to which 2 g (10 mmol) of p-toluenesulfonic acid (catalyst) and 4 g of hydroquinone (polymerization inhibitor) were added. The mixture was heated to keep 120° C. for 4 hours in nitrogen atmosphere with distilling 14 ml (0.25 mol) of ethanol away. The reaction mixture was evaporated to remove excess diethyl oxalate and then distilled under vacuum to obtain 88.1 g (yield 76.5%) of 2-ethoxalyloxyethyl methacrylate (colorless transparent liquid) (bp 98° C./0.3 mmHg).
EXAMPLE 17
A 500 ml flask equipped with a decanter, a thermometer, a stirrer and an inlet for nitrogen gas was charged with 65.1 g (0.5 mol) of 2-hydroxyethyl methacrylate and 365.4 g (2.5 mol) of diethyl oxalate, to which 2 g (10 mmol) of p-toluenesulfonic acid (catalyst) and 4 g of 2-t-butylhydroquinone (polymerization inhibitor) were added. The mixture was heated to keep about 130° C. for 3 hours in nitrogen atmosphere with distilling 22 ml (0.38 mol) of ethanol away. The reaction mixture was evaporated to remove excess diethyl oxalate and then distilled under vacuum to obtain 64.8 g (yield 76.5%) of 2-ethoxalyloxyethyl methacrylate (bp 84°-125° C./0.4 mmHg).
EXAMPLE 18
A 500 ml flask equipped with a decanter, a thermometer, a stirrer and an inlet for nitrogen gas was charged with 65.1 g (0.5 mol) of 2-hydroxyethyl methacrylate and 365.4 g (2.5 mol) of diethyl oxalate, to which 2 g (10 mmol) of p-toluenesulfonic acid (catalyst) and 4 g of 2,5-di-t-butylhydroquinone (polymerization inhibitor) were added. The mixture was heated to keep about 130° C. for 3 hours in nitrogen atmosphere with distilling 23.5 ml (0.40 mol) of ethanol away. The reaction mixture was evaporated to remove excess diethyl oxalate and then distilled under vacuum to obtain 64.8 g (yield 52.4%) of 2-ethoxalyloxyethyl methacrylate (bp 95°-125° C./0.3 mmHg).
EXAMPLE 19
A 500 ml flask equipped with a decanter, a thermometer, a stirrer and an inlet for nitrogen gas was charged with 65.1 g (0.5 mol) of 2-hydroxyethyl methacrylate and 365.4 g (2.5 mol) of diethyl oxalate, to which 2 g (10 mmol) of dibutyltin dilaurate (catalyst) and 4 g of 2,5-di-t-butylhydroquinone (polymerization inhibitor) were added. The mixture was heated to keep it at about 120° C. for 2 hours in nitrogen atmosphere with distilling 32.5 ml (0.56 mol) of ethanol away. The reaction mixture was evaporated to remove excess diethyl oxalate and then distilled under vacuum to obtain 84.2 g (yield 73.2%) of 2-ethoxalyloxyethyl methacrylate (bp 124° C./0.4 mmHg).
EXAMPLE 20
Preparation of p-ethoxalyloxyethylstyrene
A 200 ml flask equipped with a stirrer, a thermometer and a dropping funnel was charged with 14.8 g (0.1 mol) of p-hydroxyethylstyrene, 150 ml of benzene and 10.1 g (0.1 mol) of triethylamine and cooled to 10° C. To the mixture was added dropwise with stirring 13.7 g (0.1 mol) of ethoxalyl chloride for one hour at 10° C. to precipitate a hydrochloride of triethylamine (white solid). After mixting at room temperature for 2 hours, 80 g of hexane was added to complete precipitation of the hydrochloride. The hydrochloride is removed by filteration and the resultant filtrate was condensed to obtain the aimed compound. The compound was identified by 1 H NMR (360 Mz) and IR. ##STR7##
1 -NMR g; 1.4 (3H,t), d; 3.1 (2H,t), f; 4.4 (2H,q), e; 4.5 (2H,t), a; 5.25-5.75 (2H,dd), b; 6.75 (1H,dd), c; 7.2-7.5 (4H,m).
IR (cm -1 ) ##STR8##
EXAMPLE 21
A 200 ml flask equipped with a decanter, a condenser, a stirrer and a dropping funnel was charged with 50 g of butyl acetate and heated to 100° C. To the content was added dropwise 30.75 g of 2-ethoxalyloxyethyl methacrylate, 35.69 g of methyl methacrylate, 21.92 g of n-butyl acrylate and 1.33 g of azobisisobutylonitrile for 2 hours. After mixing for 30 minutes, 0.88 g of azobisisobutylonitrile and 17.8 g of butyl acetate were added dropwise for 30 minutes. It was mixed with heating for 1.5 hours and cooled to obtain transparent and light yellow polymer (Mn=14,200, Mw=37,500, α=2.63).
EXAMPLE 22
A 200 ml flask equipped with a decanter, a condenser, a stirrer and a dropping funnel was charged with 70 g of butyl acetate and 20 g of butanol, and heated to 110° C. To the content was added dropwise 16.4 g of 2-ethoxalyloxyethyl methacrylate, 50.0 g of methyl methacrylate, 24.3 g of n-butyl acrylate, 9.3 g hydroxyethyl methacrylte and 1.5 g of azobisisobutylonitrile for 3 hours. After mixing for 30 minutes, 0.5 g of azobisisobutylonitrile and 10.0 g of butyl acetate were added dropwise for 30 minutes. It was mixed with heating for 1.5 hours and cooled to obtain transparent and light yellow polymer (Mn=9,730, Mw=30,942, α=3.17).
EXAMPLE 23
A 200 ml flask equipped with a decanter, a condenser, a stirrer and a dropping funnel was charged with 42.9 g of xylene and 1 g of Kaya Ester-O (t-butylperoxy-2-ethylhexanoate available from Akzo Chemical Company), and heated to 140° C. To the content was added dropwise 41.0 g of 2-ethoxalyloxyethyl methacrylate, 40.0 g of methyl methacrylate, 19.0 g of n-butyl acrylate and 4.0 g of azobisisobutylonitrile for 2 hours. After mixing for 30 minutes, 10.0 g of xylene was added dropwise for 30 minutes. It was mixed with heating for 1.5 hours and cooled to obtain transparent and light yellow polymer (Mn=2,799, Mw=5,695, α=2.03).
EXAMPLE 24
A 200 ml flask equipped with a decanter, a condenser, a stirrer and a dropping funnel was charged with 27.0 g of butyl acetate and heated to 110° C. To the content was added dropwise 30.0 g of 2-ethoxalyloxyethyl methacrylate and 0.45 g of azobisisobutylonitrile. After mixing for 30 minutes, 0.15 g of azobisisobutylonitrile and 3.0 g of butyl acetate were added dropwise for 30 minutes. It was mixed with heating for 1.5 hours and cooled to obtain transparent and light yellow polymer (Mn=8,050, Mw=17,240, α=2.14).
EXAMPLE 25
A 100 ml flask equipped with a decanter, a condenser, a stirrer and a dropping funnel was charged with 13.1 g of xylene and heated to 120° C. A mixture of 33.8 g of the product of Example 8, 3.8 g of Kaya Ester-O, 3.8 g of alpha-methylstyrene dimer and 3.8 g of xylene was added dropwise for 3 hours. After mixing for 30 minutes, 0.38 g of Kaya Ester and 3.3 g of xylene were added dropwise for one hour. It was mixed with heating for 1.5 hours and cooled to obtain transparent and light yellow liquid (Viscosity=253 cp).
EXAMPLE 26
A 100 ml flask equipped with a decanter, a condenser, a stirrer and a dropping funnel was charged with 15.0 g of xylene and heated to 130° C. A mixture of 32.7 g of the product of Example 8, 9.3 g of 2-hydroxyethyl methacrylate, 2.5 g of butanol, 3.1 g of n-butyl methacrylate, 4.5 g of Kaya Ester-O and 5.0 g of alpha-methylstyrene dimer was added dropwise for 3 hours. After mixing for 30 minutes, 0.38 g of Kaya Ester and 3.3 g of xylene were added dropwise for one hour. It was mixed with heating for 1.5 hours and cooled to obtain transparent and light yellow liquid (Viscosity=99.2 cp, nonvolatile content=60.4%).
EXAMPLE 27
A 100 ml flask equipped with a decanter, a condenser, a stirrer and a dropping funnel was charged with 15.0 g of xylene and heated to 130° C. A mixture of 24.5 g of the product of Example 8, 19.2 g of FM-2, 1.35 g of n-butyl methacrylate, 5 g of alpha-methylstyrene dimer, 2.5 g of butanol and 4.5 g of Kaya Ester-O was added dropwise for 3 hours. After mixing for 30 minutes, 0.5 g of Kaya Ester and 5.0 g of xylene were added dropwise for one hour. It was mixed with heating for 1.5 hours and cooled to obtain transparent and light yellow liquid (Viscosity=74.4 cp, nonvolatile content=63.4%).
EXAMPLES 28 to 33
A 200 ml of flask equipped with a decanter, a condenser, a stirrer and a dropping funnel was charged with 21.8 g of xylene and heated to 135° C. To the content, 62.5 g of a monomer mixture shown in Table 2, 6.3 g of Kaya Ester-O and 6.3 g of xylene were added dropwise for 3 hours. After mixing for 30 minutes, 0.63 g of Kaya Ester and 5.0 g of xylene were added dropwise for one hour. It was mixed with heating for 1.5 hours and heated to remove 15 g of xylene. It was then cooled to obtain transparent and light yellow liquid. The liquid had physical properties as shown in Table 2.
TABLE 2______________________________________Example Nonvolatile Viscosity.sup.2No. Momomer mixture content.sup.1 (cps)______________________________________28 EOMA.sup.3 /MSD.sup.4 = 90/10 79 122929 EOFM-2.sup.5 /MSD = 90/10 80 21130 EOMA/MMA.sup.6 /MSD = 78 410 55.4/34.6/1031 EOMA/MMA/MDS = 76 4429 85/5/1032 EOMA/ST.sup.7 /MSD = 46.3/ 81 5760 43.7/1033 EOMA/EHA.sup.8 /MSD = 76 550 73.8/16.2/10______________________________________ .sup.1 The obtained polymer solution was heated at 130° C. for 30 minutes. The weight after heating the solution was divided by the weight before heating. The obtained value times 100 is shown in Table 2. .sup.2 Measured by an E type viscometer at 25° C. .sup.3 2Ethyloxalyloxy methacrylate .sup.4 Alphamethylstyrene dimer .sup.5 An ethoxalylated FM2 (a compound of 2hydroxyethyl methacrylate ringopened with average two epsiloncaprolantone molecules; available from Daicel Chemical Industries Co., Ltd.) .sup.6 Methyl methacrylate .sup.7 Styrene .sup.8 2Ethylhexyl acrylate
PRODUCTION EXAMPLE 1
Acryl polyol
A one liter flask equipped with a decanter, a condenser, a stirrer and a dropping funnel was charged with 180.0 g of butyl acetate and heated to 120° C. A mixture of 142.7 g of methyl methacrylate, 87.7 g of n-butyl acrylate, 69.6 g of 2-hydroxyethyl methacrylate and 4.5 g (1.5 wt %/monomers) of azobisisobutylonitrile was added dropwise for 3 hours. After mixing for 30 minutes, 1.5 g (0.5 wt %/monomers) of azobisisobutylonitrile and 30.0 g of butyl acetate were added dropwise for 30 minutes. It was mixed with heating for 1.5 hours and cooled to obtain transparent and light yellow polymer (Mn=8,870, Mw=20,600, OH value=100, α=2.31).
PRODUCTION EXAMPLE 2
Acryl polyol
A 200 ml flask equipped with a decanter, a condenser, a stirrer and a dropping funnel was charged with 21.8 g of xylene and heated to 135° C. To the content, 62.5 g of a monomer mixture (FM-2/styrene/isobutyl methacrylate/alpha-methylstyrene dimer=55.2/10.2/27.4/10.2), 6.3 g of Kaya Ester-O and 6.3 g of xylene were added dropwise for 3 hours. After mixing for 30 minutes, 0.63 g of Kaya Ester-O and 5.0 g of xylene were added dropwise for one hour. After mixing with heating for 1.5 hours, it was heated to remove 15 g of xylene. The obtained solution was cooled to room temperature to obtain transparent and light yellow polymer. The polymer solution has a viscosity of 326 (E type viscometer at 25° C.) and a nonvolatile content of 70% (130° C., 30 minutes).
EXAMPLE 34
One of the products (curing agent) prepared in Examples 28 to 33 and the acryl polyol of Production Example 2 were mixed with 1 wt %/solid content of dibutyltin dilaurate. The resultant composition was coated on a tin plate by a bar coater No. 40, and then baked at 130° or 150° C. for 30 minutes. Curing properties were evaluated and the results were shown in Table 3.
TABLE 3______________________________________ AcetoneCuring agent Amount of rubbing test.sup.9(weight) the polyol 130° C. 150° C.______________________________________Ex. 28 (1.49 g) 4.04 g 11 19Ex. 29 (2.26 g) 3.00 g 9 1Ex. 30 (2.02 g) 3.43 g 10 16Ex. 31 (1.44 g) 3.76 g 7 9Ex. 32 (2.22 g) 3.15 g 10 15Ex. 33 (1.71 g) 3.81 g 9 10______________________________________ .sup.9 A piece of cloth which was saturated with acetone was wrapped on a finger and rubbed on the cured coating. Number of rubbing until the coating is peeled off is shown in Table 3.
EXAMPLE 35
A catalyst was mixed with 8.51 g of the 2-ethoxalyloxy methacrylate copolymer prepared in Example 21 and 6.49 g of the acryl polyol of Production Example 1 in an amount ratio of catalyst/resin solid content of 1 wt % to form a resin composition. The catalyst was selected from dibutyltin dilaurate (DBTL), diazabicyclooctane (DABCO) and p-toluenesulfonic acid monohydrate (PTS). Also, another resin composition which did not contain any catalyst was prepared. The resin composition was coated on a tin plate by a bar coater in a thickness of 20 microns, and then baked at 110°, 130°, 150° or 180° C. for 30 minutes. Curing properties were evaluated and the results were shown in Table 4.
TABLE 4______________________________________Curing Num- Acetone Gellation Penciltemp. ber.sup.10 Catalyst rubbing.sup.9 %.sup.11 hardness.sup.12______________________________________110° C. 1 Nothing -- -- 2 1 DBTL 5 85.8 H 2 81.8 H 1 DABCO 5 64.6 H 2 69.8 H 1 PTS -- -- 2130° C. 1 Nothing -- -- 2 1 DBTL 16 95.1 H 2 96.6 H 1 DABCO 5 84.4 H 2 83.2 H 1 PTS -- -- 2150° C. 1 Nothing 5 3.8 2H 2 2.2 2H 1 DBTL 50 99.5 2H 2 99.6 2H 1 DABCO 34 89.1 2H 2 87.3 2H 1 PTS 13 19.3 2H 2 19.3 2H180° C. 1 Nothing 6 5.8 2H 2 5.1 2H 1 DBTL 50 or more 99.7 2H 2 99.6 2H 1 DABCO 50 or more 89.8 2H 2 89.4 2H 1 PTS 10 76.6 2H 2 77.0 2H______________________________________ .sup.10 Number of times of test. .sup.11 Gellation %; The coated film was placed in a acetone refluxing condition for three hours and then dried at 60° C. for 5 hours. Th remaining film is expressed with percentage. .sup.12 Pencil hardness; the cured coating was scratched by pencils and was expressed by a hardness of a pencil when the coating was defected.
EXAMPLES 36 to 38
A 200 ml flask equipped with a decanter, a condenser, a stirrer and a dropping funnel was charged with xylene and n-butanol in an amount shown in the initial charge column of Table 5 and heated to a polymerization temperature. To the content, a monomer mixture shown in Table 5 and Kaya Ester-O were were added dropwise for 3 hours. After mixing for 5 hours, Kaya Ester-O and xylene were added dropwise in amounts shown in the after shot column of Table 5 for one hour. After mixing for 1.5 hours with heating, it was cooled to room temperature. The obtained polymer solution was transparent and light yellow. Its molecular weight, nonvolatile content and viscosity are shown in Table 6.
TABLE 5__________________________________________________________________________ Initiator After shotExam- (g) Initial charge (g) Polymerizationple Monomer mixture (g) Kaya (g) Kaya temperatureNo. EOMA HEMA HEA FM-1 ST EHMA MSD EsterO XL n-BuOH EsterO XL (°C.)__________________________________________________________________________36 24.88 4.92 4.93 7.92 2.39 10.66 6.06 6.06 18.18 9.09 0.61 4.85 120-12537 25.82 5.11 4.55 8.21 6.29 3.47 6.29 6.29 18.87 6.29 0.63 5.03 130-13538 20.66 4.09 3.64 6.57 6.29 9.06 6.29 6.29 18.87 6.29 0.63 5.03 130-135__________________________________________________________________________ EOMA; 2ethoxalyloxyethyl methacrylate HEMA; 2hydroxyethyl methacrylate HEA; 2hydroxyethyl acrylate ST; styrene EHMA; 2ethylhexyl methacrylate MSD; alphamethylstyrene dimer XL; xylene nBuOH; nbutanol
TABLE 6______________________________________Example Number average molecular NonvolatileNo. weight (α.sup.13) content Viscosity.sup.14______________________________________36 1771 (2.08) 67.4 C37 1866 (2.18) 65.7 J-K38 1866 (2.08) 72.6 S-T______________________________________ .sup.13 Weight average molecular weight divided by number average molecular weight. .sup.14 GardnerHoldt tube viscometer at 25° C.
EXAMPLE 39
One of the resins of Examples 36 to 38 was mixed with an amount of 1 wt %/resin solid content of dibutyltin dilaurate to form a resin composition. The resultant composition was coated on a tin plate by a bar coater No. 40, and then baked at 130° or 150° C. for 30 minutes. Curing properties were evaluated and the results were shown in Table 7.
TABLE 7______________________________________ Acetone rubbing test Pencil hardnessResin No. 130° C. 150° C. 130° C. 150° C.______________________________________Ex. 36 25 38 2B HBEx. 37 38 50 or more HB HBEx. 38 28 40 HB HB______________________________________
EXAMPLE 40
A 200 ml flask equipped with a decanter, a condenser, a stirrer and a dropping funnel was charged with 40 g of xylene and heated to 120° C. To the content, 200 g of a monomer mixture (FM-2/2-ethoxalyloxyethyl methacrylate/isobutyl methacrylate/alpha-methylstyrene dimer=51/32.8/10/6.2) and 9 g of Kaya Ester-O were added dropwise for 3 hours. After mixing for 30 minutes, 1 g of Kaya Ester-O and 10 g of xylene were added dropwise for one hour. After mixing with heating for 1.5 hours, it was heated to remove 30 g of xylene. The obtained solution was cooled to room temperature to obtain transparent and light yellow polymer. The polymer solution had a viscosity of 416 cps (E type viscometer at 25° C.) and a nonvolatile content of 70% (130° C., 30 minutes).
EXAMPLE 41
The resin of Example 40 was mixed with an amount of 1 wt %/resin solid content of a catalyst shown in Table 8. The resultant composition was coated on a tin plate by a bar coater No. 40, and then baked at 130° or 150° C. for 30 minutes. Curing properties were evaluated and the results were shown in Table 8.
TABLE 8______________________________________ Acetone rubbing testNumber Catalyst 130° C. 150° C.______________________________________1 Dibutyltin 23 42 dilaurate2 Dibutyltin 12 38 dichloride3 (CH.sub.3)SnI.sub.2 / 0 38 (C.sub.6 H.sub.5).sub.4 SbI4 (CH.sub.3)SnI.sub.2 / 7 38 (MoN).sub.3 PO5 H.sub.2 SO.sub.4 40 50 or more6 BF.sub.3 (Et20) 3 50 or more7 1,8-Diazabi- 19 38 cyclo[5,4,0]undecene8 1,4-Diazabi- 2 30 cyclo[2,2,2]octane9 FeCl.sub.3 8 5010 Al(i-PrO).sub.3 10 1511 Ti(i-PrO).sub.4 4 512 Diacetyltetra- 25 40 butyl stannoic acid______________________________________
EXAMPLE 42
A mixture was prepared by dissolving 52.1 g (0.4 mol) of hydroxyethyl methacrylate and 40.5 g (0.4 mol) of triethylamine in 250 ml of benzene and cooled to 2° C. To the content, a solution of 65.8 g (0.4 mol) of t-butoxalyl chloride in 200 ml of benzene was added dropwise for 3 hours while precipitating salt. After the completion of dropping, it was allowed to stand for 30 minutes without cooling to terminate reaction. The precipitated salt was filtered off and the filtrate was evaporated to obtain 99.9 g (yield 91%) of yellow liquid which was identified by IR and 1 H-NMR to find t-butoxalyloxylethyl methacrylate.
IR (cm -1 , neat); 2950 (C-H), 1760-1720 (C═O), 1640 (C═O).
1 H-NMR (ppm, in CDCl 3 , TMS Standard) e; 1.56 (s,9H), c; 1.95 (s,3H), d; 4.46 (m,4H), a or b; 5.60 (s,1H), a or b; 6.14 (s,1H), ##STR9##
EXAMPLE 43
A 500 ml flask equipped with a decanter, a condenser, a stirrer and a dropping funnel was charged with 90 g of xylene and heated to 100° C. To the content, 39.0 g of t-butoxalyloxyethyl methacrylate of Example 42, 26.2 g of n-butyl acrylate, 34.8 g of methyl methacrylate and 2.0 g of azobisisobutylonitrile were added dropwise for 3 hours. After mixing for 30 minutes, 0.2 g of azobisisobutylonitrile and 10 g of xylene were added dropwise for one hour. After mixing with heating for 1.5 hours, the obtained solution was cooled to room temperature to obtain transparent and light yellow polymer. The polymer solution had a viscosity of 243 cps °C. (E type viscometer at 25° C.) and a nonvolatile content of 50% (130° C., one hour), and had Mn=6,790, Mw=13,300, α=1.96.
EXAMPLE 44
As generally described in Example 42, the reaction was conducted with the exception that 46.4 g (0.4 mol) of 2-hydroxyethyl acrylate was employed instead of 2-hydroxyethyl methacrylate to obtain 96.6 g (yield 98.8%) of t-butoxalyloxyethyl acrylate which was identified by IR and NMR.
IR (cm -1 , neat); 2950 (C--H), 1760-1720 (C═O), 1620 (C═C), 1140 (C--O).
1 H-NMR (ppm, in CDCl 3 , TMS Standard) e; 1.54 (s,9H), d; 4.43-4.50 (m,4H), a or b; 5.88-5.90 (d,1H), c; 6.11-6.19 (d-d,1H), a or b; 6.42-6.47 (d,1H) ##STR10##
13 C-NMR (ppm, in CDCl 3 ); 9; 27.51, 4 or 5; 61.42, 4 or 5; 63.85, 8; 84.90, 1; 128.1, 2; 131.43, 6 or 7; 156.38, 6 or 7; 158.17, 3; 165.51. ##STR11##
EXAMPLE 45
A 200 ml flask equipped with a decanter, a condenser, a stirrer and a dropping funnel was charged with 45 g of xylene and heated to 100° C. To the content, 36.6 g of t-butoxalyloxyethyl acrylate of Example 44, 7.7 g of n-butyl acrylate, 5.7 g of methyl methacrylate and 1.0 g of azobisisobutylonitrile were added dropwise for 3 hours. After mixing for 30 minutes, 0.1 g of azobisisobutylonitrile and 5 g of xylene were added dropwise for 30 minutes. After mixing with heating for 1.5 hours, the obtained solution was cooled to room temperature to obtain transparent and light yellow polymer. The polymer solution had a viscosity of 83 cps (E type viscometer at 25° C.) and a nonvolatile content of 49% (130° C., one hour), and had Mn=4,800, Mw=10,090, α=2.10.
EXAMPLE 46
A mixture was prepared by dissolving 92.6 g (0.5 mol) of SIPOMER TBM (t-butylaminoethyl methacrylate available from Arcolac Company) and 50.6 g (0.5 mol) of triethylamine in 400 ml of benzene and cooled to 2° C. A solution of 68.3 g (0.5 mol) of ethoxalyl chloride in 100 ml of benzene was added dropwise for one hour. After the completion of dropping, it was allowed to mix for 1.5 hours without cooling to terminate reaction. The precipitated salt was filtered off and the filtrate was evaporated to obtain brown viscous liquid which was identified by IR and 1 H-NMR to find N-t-butyl-N-ethoxalylaminoethyl methacrylate.
IR (cm -1 , neat): 1740, 1720, 1660 (C═O),
1 H-NMR (ppm, in CDCl 3 , TMS Standard); h; 1.36 (t,3H), f; 1.51 (s,9H), e; 3.58 (t,3H), c; 1.95 (s,3H), d and g; 4.30 (m,4H), a or b; 5.62 (s,1H), a or b; 6.15 (s,1H). ##STR12##
13 C-NMR (ppm, in CDCl 3 ); 12; 13.81, 3; 16.17, 8; 28.11, 6; 44.06, 7; 57.78, 11; 61.85, 5; 63.25, 1; 126.29, 2; 135.64, 8 or 9; 163.15, 8 or 9; 163.53, 4; 166.66. ##STR13##
EXAMPLE 47
A 200 ml flask equipped with a decanter, a condenser, a stirrer and a dropping funnel was charged with 35 g of xylene and heated to 135° C. To the content, 60.0 g of N-t-butyl-N-ethoxalylaminoethyl methacrylate of Example 46, 20.0 g of isobutylmethyl methacrylate, 10.0 g of styrene, 10.0 g of alpha-methylstyrene dimer and 10.0 g of Kaya Ester-O were added dropwise for 3 hours. After mixing for 30 minutes, 1.0 g of Kaya Ester-O and 8 g of xylene were added dropwise for one hour. After mixing with heating for 1.5 hours, the obtained solution was cooled to room temperature to obtain transparent and light yellow polymer. The polymer solution had a viscosity of 193 cps (E type viscometer at 25° C.) and a nonvolatile content of 64% (130° C., one hour), and had Mn=1,345, Mw=1,990, α=1.48.
EXAMPLE 48
A three liter flask was charged with 253.86 g (2.0 mol) of oxalyl chloride and 1200 ml of benzene and cooled with stirring. A solution of 120.2 g (2.0 mol) of isopropyl alcohol, 212.5 g (2.0 mol) of triethylamine and 400 ml of benzene was added dropwise for 3 hours. After the completion of dropping, mixing was continued at 20° C. for 2 hours. The solution became blown and precipitated crystal. After adding 600 ml of hexane to the reaction mixture, the precipitated solid was filtered off and the filtrate was condensed. It was then distilled under vacuum to obtain 74.4 g (yield 17.7%) of isopropoxalyl chloride. (bp 100°-105° C./ 150 mmHg)
1 H-NMR (ppm): 1.38 (d,6H), 5.20 (m,1H).
Next, a 500 ml reaction vessel was charged with 25 g (0.17 mol) of the obtained isopropoxalyl chloride and 150 ml of benzene and cooled to 5° C. with ice. A mixture of 27.9 g (0.214 mol) of 2-hydroxyethyl methacrylate and 24.1 g (0.238 mol) of triethylamine was added dropwise for 1.5 hours with mixint while precipitating white solid. Mixing was continued at 5° C. for 1.5 hours and filtered. The filtrate was condensed and then distilled under vacuum to obtain 17.6 g (yield 43.3%) of isopropoxalyloxyethyl methacrylate of bp. 112° C./0.3 mm Hg.
IR (cm -1 , neat); 3500, 2980, 1760, 1740, 1720, 1635, 1095, 680.
1 H-NMR (ppm, in CDCl 3 , TMS Standard); 1.33 (d,6H), 1.92 (s,3H), 4.41 (m,2H), 4.52 (m,2H), 5.17 (m,1H), 5.60 (s,1H), 6.12 (s,1H).
EXAMPLE 49
A 200 ml flask equipped with a decanter, a condenser, a stirrer and a dropping funnel was charged with 50 ml of xylene and heated to 110° C. To the content, 52.2 g of isopropoxalyloxyethyl methacrylate, 27.8 g of cyclohexyl methacrylate, 10.0 g of styrene, 10.0 g of alpha-methylstyrene dimer and 10.0 g of t-butylperoxy-2-ethyl hexanate were added dropwise for 3 hours. After mixing at 110° C. for 30 minutes, 1.0 g of t-butylperoxy-2-ethyl hexanate and 6.0 g of xylene were added dropwise for 30 minutes. It was then mixed at 110° C. for 1.5 hours to obtain a copolymer having a nonvolatile content of 58.6% (130° C., 60 minutes), and had Mn=1,870, Mw=3,240, α=1.73.
EXAMPLE 50
An amount of 1 wt %/resin solid content of dibutyltin dilaurate was mixed with 2.36 g of the acryl polyol of Production Example 1 and 2.00 g of the polymer prepared in Example 47 to form a curable composition. The resultant composition was coated on a tin plate by a bar coater No. 40 in a thickness of 20 micrometers, and then baked at 180° C. for 30 minutes. The cured film had a gellation % (measured as Examle 35) of 95.3%. | A homopolymer or a copolymer comprises a polymerizable compound represented by formula (I):
A--X--COCOOR.sub.1 (I)
wherein
R 1 represents a hydrogen atom, a C 1 -C 5 alkyl group or an aryl group;
X represents an oxygen atom, a sulfur atom, --COO-- or --NR 5 --
wherein
R 5 is a hydrogen atom or a C 1 -C 5 alkyl group;
A represents a C 3 -C 18 alkenyl, alkynyl, alkenylaryl or alkenylaralkyl group, or a group represented by: ##STR1## wherein R 2 and R 3 , which may be the same or different, independently represent a hydrogen atom or a C 1 -C 5 alkyl group;
Y represents an oxygen atom or --NR 4 -- wherein R 4 represents a hydrogen atom or a C 1 -C 5 alkyl group; n is an integer of 1 to 5; m is an integer of 1 to 10; and l is 0 or an integer of 1 to 20;
with the proviso that if Y is present, X is not --NR 5 --. Additionally, disclosed are processes of preparing the homopolymer or copolymer as well as the polymerizable compound. | 2 |
CROSS REFERENCE TO RELATED APPLICATION
This application is related to provisional application U.S. Ser. No. 60/393,764 filed Jul. 3, 2002.
FIELD OF THE INVENTION
The present invention relates generally to finishing tools or coaters for applying mastic material, drywall compound or other similar material over tape joints between adjacent pieces of wallboard. More particularly, the present invention is directed towards a coater having a tensioner assembly which provides improved control for adjustably applying the proper amount of mastic over the taped joint.
BACKGROUND OF THE INVENTION
Wallboard or drywall has become the dominant material in the production of interior building partitions. In particular, interior building partitions generally comprise a series of spaced vertical studs which are used as support for preformed wallboards which are attached to the studs by the screws, nails, adhesive or the like. Typically, a paper or fiberglass tape is applied to the joint between adjacent wallboard panels. In order to provide a continuous flat surface to the wall, it is necessary to “finish” the tape joint between adjacent panels. Generally such “finishing” entails the building up or accumulation of multiple layers of mastic material over the taped joint. During the finishing process, it is important that the proper crown or profile of mastic material is applied given the amount of shrinkage that occurs when each coat of mastic material dries. Crown control is dependent upon several variables including coat thickness and the amount of water mixed in the drywall compound.
Drywall heads for applying mastic compound to finish drywall joints are known in the art. Precision Taping Tools of Arthur, Ill. produces a coater (model K-520A, K-530A, K-540A) with a flat finishing head formed with a coater body having side plates and skids or arm links adapted to engage a wall during mastic application. One wall of the coater body has a mounting plate which rotatably receives a ball member connected to a hollow arm member which allows mastic material to be moved from a pneumatic applicator to the flat finishing head. A C-spring has one end secured to a clevis integrally formed on the arm member, and another end joined to a rotatable clevis on the mounting plate. The coater body also includes a bottom cover plate, a wiper blade and a generally flat backer bar. A cam lever acts against a tensioner wire having L-shaped ends which contact the backer bar at two points. Mastic material delivered through the ball member to the interior of the coater body is controllably squeezed through a gap defined between the cover and the blade. The cam and tensioner wire are used to control the crown or profile of mastic material delivered from the finishing head.
When using the Precision Taping Tool coater, the flat backer bar relies on the viscosity of the drywall compound, the setting of the cam tensioner wire and the deflection of the cam tensioner wire/backer bar to provide the desired mastic profile. In addition, the prior art coater uses a cam having a half-round profile with an offset pivot to provide adjustability. However, as the cam moves through its travel, it reaches a point where a small adjustment of the cam lever makes abnormally large adjustments of the backer bar/blade and vice versa. In some occasions, the prior art finishing head deflects so far as to overcrown the compound making a subsequent coat “near to impossible” without scraping or sanding the joint. Further, the prior art finishing head has its cam tension or wire contacting the backer bar at two points which sometimes allows three crowns to form instead of one. It has also been established that the prior art coater does not return to its starting position each time it is lifted off the wall. It is further noted that the prior art coater skids are subject to excessive sliding friction and wear as they are drawn over the wallboard.
Accordingly, it is desirable to provide a drywall finishing head having an adjustment arrangement for enabling a greater predictability of crown or profile of mastic material delivered to the tape joint. It is also desirable to provide a drywall finishing head which moves along the wallboard with less friction and wear, and which returns to a start position each time it is lifted off the wallboard.
SUMMARY OF THE INVENTION
It is one object of the present invention to provide a drywall finishing head for applying mastic compound which may be used with a pneumatically-actuated storage body for providing a controllable flow of mastic material over a tape joint between adjacent wallboard panels.
It is also an object of the present invention to provide a drywall finishing head having a backer bar, a cam and a cam follower plate uniquely designed to provide the desired crown of mastic compound to the tapered wallboard joint.
It is another object of the present invention to provide a drywall finishing head which may be operated with arm links off the surface of the wallboards.
In one aspect of the invention, a drywall finishing head is provided for applying mastic material over a tape joint between adjacent wallboard surfaces. A coater body has a retaining assembly attached thereto for movably receiving a ball connected via an arm to a storage body for delivering mastic material through an opening in the wall to a mastic chamber in the coater body. A wiper blade extends substantially across a length of the coater body. A cover underlies the wiper blade and also extends substantially across the length of the coater body. A curved backer bar extends substantially across the length of the coater body and overlies the wiper blade. A cam assembly includes an elliptical cam rotatably mounted on the retaining assembly and acts against a cam tensioner plate fixed behind the cam. The cam further acts on a tensioner wire having a central portion extending behind the retaining assembly and end portions wrapped around the front of the retaining assembly. The wire contacts a cam follower plate engageable with the backer bar. Adjustment of the cam assembly is constructed and arranged to change the force on the backer bar so that a proper crown or profile of mastic material can be delivered to the tape joint through a gap between the cover and the wiper blade.
The coater body includes a pair of side plates to which a pair of arm links is attached, the arm links carrying a set of wheels rotatably mounted thereto and adapted to rollably engage a wallboard surface with reduced friction. A C-shaped spring has one end attached to the arm and another end attached to the ball retainer/tensioner assembly, there being an auxiliary coil spring connected between the ends of the C-shaped spring. A baffle is secured to the coater body, the baffle having a curved bottom end receiving a lower end of the wiper blade. The curved bottom end of the baffle and the cover define a restricted passage for receiving mastic material in the mastic chamber of the coater body and allowing the mastic material to pass to the gap between the cover and the wiper blade. The cam follower plate is formed with a groove having a width and a depth, the walls of the groove being engageable with the tensioner wire. The backer bar has a spring rate controlled by the width of the groove in the cam follower plate. The amount of deflection in the wiper blade is limited by the depth of the groove in the cam follower plate. The cam is moveable between a full crown setting in which the cam is out of contact with the tensioner wire and mastic material is delivered through the gap in a crown profile over the tape joint, and a full flat setting in which the cam engages the tensioner wire and mastic material is delivered through the gap in a flat profile over the tape joint.
The invention further contemplates a drywall finishing tool having a coater body provided with a cover, a wiper blade and a backer bar, and a cam acting against a tensioner wire to move the backer bar so that mastic material is controllably squeezed between a gap between the cover and the blade. The invention is improved wherein the cam is an elliptical cam rotatably mounted on a retaining assembly attached to the coater body and acting against a cam tensioner plate fixed behind the cam. The cam further acts on a tensioner wire having a central portion extending behind the retaining assembly and end portions wrapped around a front of the retaining assembly. The wire contacts a cam follower plate engageable with a curved backer bar.
Various other features, objects and advantages of the invention will be made apparent from the following description taken together with the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
The drawings illustrate the best mode presently contemplated of carrying out the invention.
In the drawings:
FIG. 1 is a perspective view of a drywall finishing head for applying mastic material to a taped wallboard joint;
FIG. 2 is an end view taken along line 2 — 2 of FIG. 1 showing a cam assembly for the finishing head in a full crown setting;
FIG. 3 is a view similar to FIG. 2 showing the cam assembly in a full flat setting;
FIG. 3A is an elevational view of a cam follower plate used in the cam assembly;
FIG. 3B is a view of the cam acting against a cam tensioner wire and the cam follower plate;
FIG. 4 is a partial sectional view of the drywall finishing head as applied along a wallboard and corresponding to the full crown setting; and
FIG. 5 is a view similar to FIG. 4 showing the drywall finishing head in the full flat setting.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to the drawings, FIG. 1 illustrates a drywall finishing head 10 embodying the present invention. The drywall finishing head or coater 10 has a generally rectangular coater body 12 with a pair of side plates 14 fixed by fasteners 16 . A pair of generally triangular shaped shoes 18 are joined to the side plates 14 by fasteners 20 . Extending downwardly from the side plates 14 is a pair of arm links 22 which are connected by fasteners 24 . The lowermost ends of the links 22 are equipped with a pair of inwardly directed, rotatable wheels 26 which are adapted to rollably engage a wallboard 56 and reduce friction as the head 10 is drawn downward along the wallboard 56 . The coater 10 also includes a bent cover 28 which overlies a wiper blade 30 and is removably joined to the coater body 12 by thumbscrews 32 . The cover 28 may be removed as desired to enable cleaning of the finishing head 10 . Attached to the other side of the coater body 12 is a retaining assembly 34 .
Referring now to FIG. 4 , the retaining assembly 34 includes a spherical cavity or ball socket 36 designed for movably receiving a ball assembly 38 . The ball assembly 38 consists of an apertured ball member 40 designed to fit into the socket 36 , a curved arm member or goose neck 42 and a coupling member 44 . The goose neck 42 has a hollow interior that allows mastic material to be moved from a pneumatically-actuated storage body 46 to the finishing head 10 . The goose neck 42 is curved so the head 10 may be parallel to the wallboard while a user is holding the storage body 46 at an angle to the wallboard 56 and head 10 . The coupling member 44 is designed to attach the finishing head 10 to the storage body 46 .
A C-shaped knee spring 48 has one end pivotally connected to a fixed clevis 50 extending from the goose neck 42 , and another end pivotally formed to a fixed clevis 52 integrally formed on the retaining assembly 34 . An auxiliary coil spring 54 is connected between the ends of the knee spring 48 . During operation of the storage body 46 and finishing head 10 , the knee spring 48 biases the head into a known orientation as illustrated in FIG. 4 . Thus, when the drywall head 10 is removed from the wallboard 56 , the head 10 returns to the position shown in FIG. 4 . The auxiliary spring 54 supplements the knee spring 48 to allow finishers the ability to operate the coater 10 with the wheels 26 off the wallboard 56 . This is necessary, for example, when coating to the edge of a window opening or when the wheels 26 would contact and make tracks in another nearby wet joint. Referring now to FIGS. 2 , 3 and 4 , the coater 10 further includes an inner baffle 58 which is J-shaped in cross section ( FIG. 4 ) and has a top end secured to the coater body 12 by fasteners 60 . A bottom end of the blade 30 is retained in the curved bottom of the inner baffle 58 . A spacer and shim assembly 62 to provide a precise relationship between the retaining assembly 34 and a backer bar/blade assembly to be described is interposed between the coater body 12 and the retaining assembly 34 and surrounds the ball member 40 .
A cam assembly for the finishing head 10 will now be described. A nut 64 has a shaft 65 which is screw threaded into the ball retainer/tensioner assembly 34 and provides a mounting surface for an elliptically shaped cam 66 having a cam lever 68 . A cam follower plate 70 is formed with a groove 72 as shown in FIGS. 3A and 3B . The cam 66 acts against a cam tensioner wire 74 having a central section 76 which runs behind the retaining assembly 34 and lies adjacent the top of the cam follower plate 70 as seen in FIG. 3B . Cam tensioner wire 74 acts against the cam follower plate 70 . The ends 78 of the cam tensioner wire 74 are bent around the ends of the retaining assembly 34 . Underlying the central portion 76 of the cam tensioner wire 74 is a cam tension plate 80 which may be fixed to the nut shaft 65 . The tensioner wire 74 contacts the cam follower plate 70 which, in turn, acts against a curved backer bar 82 which with the wiper blade 30 extends across substantially the entire length of the coater body 12 .
In operation, the coater 10 is placed over a taped joint at the topmost end thereof. As best seen in FIG. 4 , mastic compound is delivered from the storage body 46 through the goose neck 42 and aperture 84 in the ball member 40 into a mastic chamber 86 in the coater body 12 . Mastic material moves in the direction of the Arrow A and travels through the opening between the bottom of the inner baffle 58 and the bend 88 in the cover 28 . Mastic material continues to travel in the direction of Arrow B until it is dispersed from the gap between the cover 28 and the wiper blade 30 . The head 10 is moved over the tape joint from top to bottom delivering the desired crown. Most joints require multiple coats so that progressively larger coater heads 10 are used to finish the tape joint.
FIG. 4 shows the finishing head 10 in a full crown setting as shown in FIG. 2 wherein the cam lever 68 is pivoted in the direction of Arrow C. The elliptical cam 66 is out of contact with the tensioning wire 74 and the cam follower plate 70 is retracted as depicted by Arrow D in FIG. 4 so that the backer bar 82 and wiper blade 30 are bowed. Mastic material is delivered through the gap in a convex profile over the tape joint.
FIG. 5 shows the finishing head 10 in a full flat setting as shown in FIG. 3 wherein the cam lever 68 is pivoted in the direction of Arrow E. As the cam lever 68 is shifted, the elliptical cam 66 engages and deflects the tensioner wire 74 ( FIG. 3B ) thereby pushing the cam follower plate 70 in the direction of Arrow F ( FIG. 5 ). Pushing the cam follower plate 70 causes the backer bar 82 to move against the wiper blade 30 . As a result, the amount of mastic material delivered to the gap is reduced to a flat profile over the tape joint. Obviously, the cam lever 68 may be positioned over 180 degrees to determine the amount of crown (profile) to be delivered from the finishing head 10 .
It has been discovered that forming the backer bar 82 with a curved surface enhances control over the desired crown (profile) of the mastic material whereas the prior art flat backer bar relies on the viscosity of the mastic compound, the setting of the cam tensioner and the deflection of the cam tensioner. In addition, elliptical profile of the cam 66 of the present invention provides a constant change of crown as compared with the prior art half rounded cam with offset pivot wherein a small adjustment of the cam lever makes abnormally large adjustments of the backer bar and blade. In the present design, the spring rate of the backer bar 82 is controlled by the width of the groove 72 in the cam follower plate 70 . A wider groove 72 provides a lower (softer) spring rate than a narrow one. The prior art finishing head does not provide for this. The amount of blade deflection is limited by the depth of the groove 72 in the cam follower plate. This provides control over the profile of the compound yet allows the blade to deflect slightly if it hits something solid without lifting the outer edges of the coater off the wall. The prior art system would deflect so far as to overcrown the compound making a subsequent coat “near to impossible” without scraping or sanding the joint. In the finishing head 10 described herein, the bottom of the cam follower plate 70 provides springable support for the backer bar 82 . The prior art device has the cam tensioner wire contacting the backer bar at two points which can result in formation of three crowns instead of one. As mentioned previously, the mounting of the knee spring 48 provides a return position for the coater head 10 . The addition of the auxiliary spring 54 provides finishers with the ability to operate the coater 10 with the wheels 26 off the surface of the wallboard 56 . In the present head 10 , the U-shaped tensioner wire 74 increases the force applied to the backer bar 82 so that the proper crown could be achieved on each of the coats. Crown control is necessary because of the amount of shrinkage that occurs when each coat dries. Further, the cam adjuster is shimable to allow for setting the relaxed convex travel of the blade 30 whereas the only adjustment in the prior art head is to bend the tensioner spring.
While the invention has been described with reference to a preferred embodiment, those skilled in the art will appreciate that certain substitutions, alterations and omissions may be made without departing from the spirit thereof. Accordingly, the foregoing description is meant to be exemplary only, and should not be deemed limitative on the scope of the invention as set forth with the following claims. | A drywall finishing head is provided for applying mastic material over a tape joint between adjacent wallboard surfaces. The finishing head includes a coater connected to a pneumatic applicator for delivering the mastic material. A wiper blade extends across the length of the coater with a cover underlying the wiper blade and a backer bar overlying the wiper blade. A cam assembly is rotatably mounted on a tensioning portion of the coater. Adjustment of the cam assembly is constructed and arranged to change the force of the backer boar so that a proper crown or profile of mastic material can be delivered to the tape joint through a gap between the cover and the wiper blade. | 4 |
CROSS-REFERENCE TO RELATED APPLICATIONS
The invention herein described and claimed relates to U. S. patent application Ser. No. 09/405,461, entitled Magnetically Tunable Resonance Frequency Beam Utilizing A Stress-Sensitive Film by J. K. Davis et al., filed on even date herewith, the entire disclosure of which is incorporated herein by reference.
The invention herein described and claimed relates to U.S. patent aplication Ser. No. 09/405, 924 , entitled Piezoelectrically Tunable Resonance Frequency Beam Utilizing A Stress-Sensitive Film by T. G. Thundat et al., filed on even date herewith, the entire disclosure of which is incorporated herein by reference.
The United States Government has rights in this invention pursuant to contract no. DE-AC05-96OR22464 between the United States Department of Energy and Lockheed Martin Energy Research Corporation.
FIELD OF THE INVENTION
The present invention relates to methods and apparatus for detecting particular frequencies of vibration, and especially for detecting and selecting particular frequencies of vibration using detection and selection apparatus comprising electrostatically-tunable beam members such as cantilevers and very small cantilevers, often called microcantilevers.
BACKGROUND OF THE INVENTION
The resonance frequencies of a beam occur at discrete values based on the geometrical and mechanical properties of the beam and the environment in which it is located. The efficiency of resonance is measured by the quality factor (or Q-factor), where large Q-factors correspond to high efficiency. High-Q beams such as cantilever beams can be used as efficient listening devices for particular frequencies, with much higher sensitivity and specificity for particular acoustic bands of interest in comparison to conventional acoustic transducers. Moreover, microcantilevers, which are only a few hundred microns in length, are also much more simple to produce and could be far smaller in comparison to standard microphone technologies. As an inevitable consequence of their high specificity, one would need an exorbitant number of fixed-frequency cantilevers to cover a broad frequency spectrum. Because of this simple reason cantilever-based listening devices have not attracted significant attention. Thus, it is desirable to make a high-Q cantilever that uses an electrostatic method to achieve broad frequency tunability. The resonance frequency of such a cantilever might be changed by varying an electrical charge, potential or voltage (hereinafter referred to as potential) and thereby varying electrostatic attraction or repulsion (hereinafter referred to as electrostatic force) acting upon the cantilever.
OBJECTS OF THE INVENTION
Accordingly, it is an object of the present invention to provide a new and improved method and apparatus for tuning the resonance frequency of a beam such as a cantilever element, and more specifically to provide a new method and apparatus for tuning the resonance frequency of a beam such as a cantilever element by varying a voltage applied to the beam.
Further and other objects of the present invention will become apparent from the description contained herein.
SUMMARY OF THE INVENTION
In accordance with one aspect of the present invention, the foregoing and other objects are achieved by an electrostatically-tunable beam for detecting a particular frequency of acoustic vibration and for selecting a particular frequency of acoustic vibration out of a mixture of frequencies which comprises: a beam element having an end and a surface, and being fixedly disposed on the end; a stress-sensitive means for sensing stress selected from the group consisting of: a stress sensitive coating having a stiffness that varies with the stress therein affixed on the surface of the beam element and the beam element material having a stiffniess that varies with the stress therein; a first electrical conductor means for conducting electricity selected from the group consisting of: an electrically conductive coating disposed on a surface of the beam element and the electrical conductivity of the beam element material; a second electrical conductor means for conducting electricity fixedly disposed generally parallel to the first electrical conductor means and separated from the first electrical conductor means by a gap formed therebetween; electrical potential means suitably disposed and connected for providing electrical potentials upon the first electrical conductor means and the second electrical conductor means to cause electrostatic force between the first electrical conductor means and the second electrical conductor means whereby electrostatic force therebetween causes the beam element to bend, thereby producing a change in stress in the stress-sensitive means and a change in the resonance frequency of the electrostatically-tunable beam.
In accordance with a second aspect of the present invention, the foregoing and other objects are achieved by a method for detecting a particular frequency of acoustical vibration in a mixture of frequencies which comprises the steps of: providing an electrostatically-tunable beam comprising a beam element having an end and a surface and being fixedly disposed on the end; a stress-sensitive means for sensing stress selected from the group consisting of: a stress sensitive coating having a stiffness that varies with the stress therein affixed on the surface of the beam element and the beam element material having a stiffness that varies with the stress therein; a first electrical conductor means for conducting electricity selected from the group consisting of: an electrically conductive coating disposed on a surface of the beam element and the electrical conductivity of the beam element material; a second electrical conductor means for conducting electricity fixedly disposed generally parallel to the first electrical conductor means and separated from the first electrical conductor means by a gap formed therebetween; and electrical potential means suitably disposed and connected for providing electrical potentials upon the first electrical conductor means and the second electrical conductor means; exposing the beam element to the mixture of frequencies; activating the electrical potential means to cause electrostatic force between the first electrical conductor means and the second electrical conductor means whereby electrostatic force therebetween causes the beam element to bend thereby producing a change in stress in the stress-sensitive means and a change in the resonance frequency of the electrostatically-tunable beam to permit the electrostatically-tunable beam to respond resonantly at the particular frequency; and determining from the resonance response of the electrostatically-tunable beam whether the particular frequency of vibration is detected.
In accordance with a third aspect of the present invention, the foregoing and other objects are achieved by a method for selecting a desired frequency of acoustical vibration from a mixture of frequencies which comprises the steps of: providing an electrostatically-tunable beam comprising a beam element having an end and a surface, and being fixedly disposed on the end; a stress-sensitive means for sensing stress selected from the group consisting of: a stress sensitive coating having a stiffness that varies with the stress therein affixed on the surface of the beam element and the beam element material having a stiffniess that varies with the stress therein; a first electrical conductor means for conducting electricity selected from the group consisting of: an electrically conductive coating disposed on a surface of the beam element and the electrical conductivity of the beam element material; a second electrical conductor means for conducting electricity fixedly disposed generally parallel to the first electrical conductor means and separated from the first electrical conductor means by a gap formed therebetween; and electrical potential means suitably disposed and connected for providing electrical potentials upon the first electrical conductor means and the second electrical conductor means; activating the electrical potential means to cause electrostatic force between the first electrical conductor means and the second electrical conductor means whereby electrostatic force therebetween causes the beam element to bend thereby producing a change in stress in the stress-sensitive means and a change in the resonance frequency of the electrostatically-tunable beam to establish the resonance frequency of the electrostatically-tunable beam at the desired frequency; and exposing the electrostatically-tunable beam to the mixture of frequencies to excite the electrostatically-tunable beam to vibrate at a desired resonance frequency whereby the particular frequency desired is selected out of the mixture of frequencies.
BRIEF DESCRIPTION OF THE DRAWINGS
In the drawings:
FIGS. 1 a , 1 b , 1 c , and 1 d show a preferred method for varying cantilever resonance frequency wherein an electrically conductive coating is applied to the cantilever.
FIGS. 2 a , 2 b , 2 c , 2 d , and 2 e show an alternate design for a cantilever assembly wherein the cantilever itself comprises an electrically conductive material in accordance with the present invention.
FIGS. 3 a , 3 b , 3 c , 3 d , and 3 e show a cantilever beam comprising a material that exhibits an intrinsic change in stiffness upon bending in accordance with the present invention.
FIG. 4 shows an example of an optical detection method in accordance with the present invention.
FIG. 5 shows an array of multiple cantilevers having different geometries which can be used as an ensemble to cover an acoustic spectrum in accordance with the present invention.
Like elements in the figures are indicated by like numerals.
For a better understanding of the present invention, together with other and further objects, advantages and capabilities thereof, reference is made to the following disclosure and appended claims in connection with the above-described drawings.
DETAILED DESCRIPTION OF THE INVENTION
The claimed invention is based on the concept of changing the resonance frequency of a cantilever by changing its stiffness. The resonance frequency, ν, of an oscillating cantilever can be expressed as υ = 1 2 π K m * ( 1 )
where K is the stiffness and m* is the effective mass of the cantilever. Note that m*=nm b , where m b is the mass of the cantilever beam and the value of n is about 0.24 for a rectangular cantilever.
There are several approaches by which the resonance frequency of a cantilever can be varied. The approach described herein involves the application of a stress sensitive film to the cantilever surface. Young's Modulus for many polymers varies with applied stress due to changes in bond length of the constituent molecules.
If the cantilever is coated with or comprises a stress-sensitive material, the stiffness can be changed by bending the cantilever. The stress-sensitive material may preferably be selected from but not limited to the group consisting of metals, metal alloys, dielectric materials, polymeric materials and combinations thereof. Specific examples of such polymeric materials include but are not limited to such polymers as polycarbonate of visphenol, poly [N,N′-(p,p′- oxydiphenylene) pyromellitimide], poly (viny chloride), and the like. Many other polymers are known to the skilled artisan which perform as described herein. This bending can be easily effected by electrostatic means. When the length of the cantilever is much larger than the width, Hooke's Law for small deflections relating the curvature with effective modulus, Y, and moment, M, is given by 2 z y 2 = M YI ( 2 )
where d 2 z/dy 2 represents I, y represents distance, and z represents deflection.
The effective modulus Y in isotropic elasticity is E/( 1 −υ) where E is Young's Modulus and υis Poisson's ratio for the substrate. For rectangular cantilevers, the area moment of inertia I is given by Wt 3 /12, where W is the width and t is the thickness. The moment due to stress δs is given as δs Wt/2 . Using the moment equation 2 can be written in the form of Stoney's formula as 1 R = 6 ( 1 - υ ) δ s Et 2 ( 3 )
where the reciprocal of the radius of curvature, R, equals d 2 z/dy 2 . The displacement and surface stress are related by Equation 2. Taking into account the boundary conditions of a cantilever, Equation 2 can be solved and the displacement of the cantilever, z, can be written as z = [ 3 ( 1 - υ ) L 2 t 2 E ] δ s ( 4 )
where L is the length of the cantilever. Bending can be accomplished by electrostatic deflection of the cantilever. Differential surface stress, δs, induced in the cantilever or in a stress-sensitive coating located on the surface of the cantilever changes the effective rigidity of the cantilever, resulting in a shift in stiffness from K to (K +δK ). Therefore Equation 1 can be rewritten as v 2 = 1 2 π K + δ K m * ( 5 )
where the initial resonance frequency υ 1 , changes to υ 2 due to surface stress. By using stress-sensitive materials in or on the cantilever, large values of δK can be obtained for small changes in surface stress.
A preferred method for varying cantilever resonance frequency is shown in FIGS. 1 a and 1 b , which represent side views of an electrostatically-tunable cantilever. In FIG. 1 a , a cantilever 2 has a conductive coating 4 and a stress-sensitive coating 6 applied to one surface. The conductive coating on the cantilever is separated from a second conductor 8 by a gap formed between the second conductor 8 and the cantilever 2 . The cantilever 2 may consist of any of a number of dielectric materials, such as silicon nitride or silicon dioxide, while the conductive layers 4 , 8 may preferably be comprised of metals such as gold or platinum or some other conductive material. An electrical potential is applied across the gap formed between the conductors 4 , 8 by appropriate connections 9 , 11 to a potential source 10 . This potential source 10 may be a static potential that is controlled by a switch 12 , or it may be a time-varying pattern such as a sinusoid or a triangular waveform. When the switch 12 is closed and a potential is applied, electrostatic force between the two conductors causes the cantilever to bend, producing a change in stress in coating 6 that results in a change in stiffness and concomitant change in resonance frequency. The magnitude of the change in resonance frequency is controlled by the extent of the bending, which is in turn controlled by the magnitude of the applied electrical potential.
In FIGS. 1 a and 1 b , opposite-polarity electrical potentials are shown to be applied between conductors 4 , 8 to cause an electrostatic attraction therebetween. In the case of opposite-polarity potentials, conductors 4 , 8 must be electrically insulated from each other.
In FIGS. 1 c and 1 d , electrical potentials of like polarity are shown to be applied via connections 11 , 11 ' to conductors 4 , 8 to cause an electrostatic repulsion therebetween. In such an embodiment electrical insulation between 4, 8 may not be necessary. The potential source is generally grounded by appropriate connection 9 to a ground 7 .
Another embodiment for the cantilever assembly is shown in FIGS. 2 a - 2 b . Here, the cantilever itself 14 is comprised of a conductive material, with a stress-sensitive coating 16 applied to one side. An insulating spacer 18 separates the conductive cantilever 14 from a second conductor 20 . A potential source 22 is applied to the two conductors 14 , 20 as described above via connectors 21 , 23 to cause an electrostatic attraction therebetween. A switch 24 may be used to control the application of the electrical potential, or a time-varying source may be used, as in the previous embodiment.
In FIGS. 2 c - 2 e , electrical potentials of like polarity are shown to be applied via connections 23 , 23 'to conductors 14 , 20 to cause an electrostatic repulsion therebetween. In such an embodiment electrical insulation (spacer 18 ) between 14 , 20 may not be necessary, and connector 23 'would also not be necessary, as shown in FIG. 2 e . The potential source is generally grounded by appropriate connection 17 to a ground 15 .
Yet another embodiment shown in FIGS. 3 a and 3 b uses a cantilever beam comprising a material that exhibits an intrinsic change in stiffness upon bending. A conductive cantilever 26 is separated by an insulating spacer 28 from a second conductor 30 . Imposition of a potential source to the conductors 26 , 30 via connections 31 , 33 as described above causes the cantilever to bend, resulting in a change in stress, stiffness, and hence resonance frequency. A switch 34 or time-varying potential source may be used to control the resonance frequency of the cantilever as a function of time.
In FIGS. 3 c - 3 e , electrical potentials of like polarity are shown to be applied via connections 33 , 33 'to conductors 26 , 30 to cause an electrostatic repulsion therebetween. In such an embodiment electrical insulation (spacer 28 ) between 26 , 30 may not be necessary, and connector 33 'would also not be necessary, as shown in FIG. 2 e . The potential source is generally grounded by appropriate connection 31 to a ground 29 .
The tuning range available to an individual cantilever as shown in the FIGS. will depend on the initial stiffness of the cantilever beam, the extent of bending exerted on the beam, and the change in stress for the stress sensitive material. To effect high sensitivity detection of acoustic energy, the cantilever is electronically tuned to the appropriate resonance frequency, where it will respond by vibrating in resonance with the acoustic signal. This vibration can be detected by any of several common means, including optical detection of cantilever deflection, changes in piezoelectricity of coatings applied to the cantilever, capacitance variation between the cantilever and a fixed surface, piezoresistance of cantilever beam, or changes in tunneling current or capacitance between the cantilever and a stationary electrode. These methods are all well-known to the artisan skilled in atomic force microscopy for sensitive detection of cantilever deflection. An example of the optical deflection means is shown in FIG. 4 . Here, vibration of a cantilever 36 is monitored using a diode laser 38 . Light 40 emitted from the laser 38 is reflected from the end of the cantilever 36 . The reflected light 42 sweeps across a position sensitive photodiode 44 at the frequency of cantilever vibration, indicated by arrow 41 . Output 46 from the photodiode 44 is amplified by an amplifier 48 and the amplified signal 50 is fed into a counting circuit 52 . The number of cycles per unit time observed by the counter is used to determine the frequency of vibration. The amplitude of the output signal 50 is monitored by an analog differentiation circut 54 to determine the magnitude of the cantilever oscillation.
To detect a broad range of frequencies, it may be desirable to use an array of cantilevers, each element of which is individually tuned for optimal response over a portion of the total acoustic range. A possible configuration is shown in FIG. 5, where an array 55 of cantilevers 56 having different geometries are used as an ensemble to cover an acoustic spectrum. Each element may be tuned during manufacture to assure the preferred response within its functional range. A possible packaging configuration for an array of cantilevers might include all readout electronics on a single monolithic device. Such a device could be manufactured using standard integrated circuit production methods, and would require the use of no additional discrete components. As such, it could be considerably smaller, less expensive, and more rugged than other available acoustic monitoring technologies.
The claimed invention provides a number of advantages and features:
Tunability —The method provides a means for achieving high sensitivity and high selectivity through the use of tunable, high-Q resonance frequency.
Simplicity —Resonance frequency is inherently simple to measure, and the small devices can be manufactured in arrays having desired acoustic response characteristics.
Speed —Much faster response time (tens of μs) than conventional acoustic detectors (tens of ms) due to extremely small size and large Q value.
Sensitivity —The sensitivity can be controlled by the geometry of the cantilevers and the coating on the cantilevers. This can be made very broadband, narrow band, low pass, or high pass.
Size —Current state-of-the-art in micro-manufacturing technologies suggest that a sensor array and control electronics could be housed in a standard transistor package.
Low power consumption —The power requirement are estimated to be in sub-mW range for individual sensors allowing the use of battery or photovoltaic power.
Low cost —No exotic or expensive materials or components are needed for sensor fabrication. Electronics for operation and control are of conventional design, and are relatively simple and inexpensive.
Wide range —A wide range of the acoustic spectrum could be detected using an array of cantilevers with different initial K values.
A number of alternative embodiments are possible. The stiffness of the cantilevers may also be changed by using materials that change rigidity under the action of an imposed electric field or potential. The device herein before described is made of cantilever-type beams with one end free to vibrate. However, a similar device may be constructed using beams of other configurations, such as simply supported beams wherein both ends are supported, free to rotate; or beams with both ends fixed, not free to rotate; with one end fixed and one end supported and free to rotate; and other simple and compound beam structures and combinations, such as triangular beams having two corners fixed and the third corner free.
Alternative uses are also possible. For example, in addition to being used to detect particular frequencies of acoustic vibration, the apparatus may be used as a narrow band filter to select a particular frequency out of a mixture of acoustic frequencies.
Applications for the claimed invention are numerous and varied, and may include: passive listening devices for detection of concealed objects, including submarines and buried structures, location of fish schools, or detection of leaking pipelines; passive flow monitoring based on acoustic signatures of the Venturi Effect and other phenomenon; replacing microphones used to detect pending mechanical failure of machine components (for example, the gear box of helicopters, machine tools, power plant turbines, or automobile engines); detection of thermal or mechanical stress in objects or structures based on passive acoustic signatures; burglar and intrusion detectors and alarms for buildings and vehicles; simplified voice recognition systems; and cochlear implants for hearing impaired people.
While there has been shown and described what are considered the preferred embodiments of the invention, it will be obvious to those skilled in the art that various changes and modifications can be made therein without departing from the scope of the inventions defined by the appended claims. | Methods and apparatus for detecting particular frequencies of acoustic vibration utilize an electrostatically-tunable beam element having a stress-sensitive coating and means for providing electrostatic force to controllably deflect the beam element thereby changing its stiffness and its resonance frequency. It is then determined from the response of the electrostatically-tunable beam element to the acoustical vibration to which the beam is exposed whether or not a particular frequency or frequencies of acoustic vibration are detected. | 6 |
TECHNICAL FIELD
This disclosure relates to electrified vehicles, and more particularly, but not exclusively, to a battery testing system and method for evaluating the response of a battery cell to an unintended puncture or other cell damage.
BACKGROUND
Hybrid electric vehicles (HEV's), plug-in hybrid electric vehicles (PHEV's), battery electric vehicles (BEV's), fuel cell vehicles and other known electrified vehicles differ from conventional motor vehicles in that they are powered by one or more electric machines (i.e., electric motors and/or generators) instead of or in addition to an internal combustion engine. High voltage current is typically supplied to the electric machines by one or more batteries that store electrical power.
Electrified vehicle batteries may employ one or more battery cells, such as lithium-ion battery cells. Tests for evaluating the safety of such battery cells are known. One common evaluation test is referred to as the nail penetration test. During this test, a nail is driven through a battery cell to create a short circuit inside the battery cell. In response to the destructive test, battery temperatures and voltages are measured. One drawback to known battery penetration tests is that these tests reveal little to no detail concerning the internal response of the battery cell.
SUMMARY
A battery testing system according to an exemplary aspect of the present disclosure includes, among other things, a penetrating device and an impedance meter electrically connected to the penetrating device.
In a further non-limiting embodiment of the foregoing system, the penetrating device is a nail.
In a further non-limiting device of either of the foregoing systems, the penetrating device is movable between a first position and a second position to puncture and short circuit a battery cell.
In a further non-limiting device of any of the foregoing systems, the impedance meter is connected to a positive terminal or a negative terminal of the battery cell and is configured to measure impedance and voltage data between the penetrating device and a terminal of the battery cell.
In a further non-limiting device of any of the foregoing systems, the impedance meter is connected to a positive terminal and a second impedance meter is connected to a negative terminal of the battery cell.
In a further non-limiting device of any of the foregoing systems, a voltage meter is configured to measure a voltage across a positive terminal and a negative terminal of the battery cell.
In a further non-limiting device of any of the foregoing systems, a temperature sensor is configured to measure a temperature of the battery cell.
In a further non-limiting device of any of the foregoing systems, a tool moves the penetrating device between a first position and a second position to puncture a battery cell.
In a further non-limiting device of any of the foregoing systems, the penetrating device includes a first portion having a non-conductive coating and a second portion that excludes the non-conductive coating.
In a further non-limiting device of any of the foregoing systems, the second portion of the penetrating device includes a pointed tip.
A battery testing system according to another exemplary aspect of the present disclosure includes, among other things, a battery cell, a penetrating device configured to short circuit the battery cell and an impedance meter electrically connected to the battery cell and the penetrating device and configured to measure at least impedance data between the battery cell and the penetrating device.
In a further non-limiting embodiment of the foregoing system, the impedance meter is electrically connected between a positive terminal or a negative terminal of the battery cell and the penetrating device.
In a further non-limiting device of either of the foregoing systems, a second impedance meter is electrically connected to the penetrating device and a terminal of the battery cell.
In a further non-limiting device of any of the foregoing systems, the impedance meter is connected to a positive terminal of the battery cell and the second impedance meter is connected to a negative terminal of the battery cell.
In a further non-limiting device of any of the foregoing systems, a data acquisition system is configured to collect and analyze the impedance data from the impedance meter.
A method according to another exemplary aspect of the present disclosure includes, among other things, creating a short circuit in a battery cell and measuring impedance data associated with the battery cell in response to the step of creating the short circuit.
In a further non-limiting embodiment of the foregoing method, the step of creating the short circuit includes penetrating the battery cell with a penetrating device.
In a further non-limiting embodiment of either of the foregoing methods, the method includes measuring voltage data associated with the battery cell.
In a further non-limiting embodiment of any of the foregoing methods, the method includes calculating a transient current through the short circuit using the impedance data and the voltage data.
In a further non-limiting embodiment of any of the foregoing methods, the method includes electrically connecting an impedance meter to a penetrating device and the battery cell.
The embodiments, examples and alternatives of the preceding paragraphs, the claims, or the following description and drawings, including any of their various aspects or respective individual features, may be taken independently or in any combination. Features described in connection with one embodiment are applicable to all embodiments, unless such features are incompatible.
The various features and advantages of this disclosure will become apparent to those skilled in the art from the following detailed description. The drawings that accompany the detailed description can be briefly described as follows.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 schematically illustrates a powertrain of an electrified vehicle.
FIG. 2 illustrates a first embodiment of a battery testing system.
FIG. 3 illustrates a second embodiment of a battery testing system.
FIG. 4 illustrates a third embodiment of a battery testing system.
FIG. 5 illustrates a fourth embodiment of a battery testing system.
FIG. 6 illustrates an exemplary penetrating device that may be employed by a battery testing system.
DETAILED DESCRIPTION
This disclosure relates to a battery testing system and method for evaluating the safety and design of a battery cell. The inventive battery testing system collects alternating current (AC) impedance data between a conductive penetrating device, such as a nail, and the battery cell. The impedance data may be collected using one or more impedance meters. The impedance data is collected and analyzed to calculate a transient current through a short circuit created in the battery cell by the penetrating device. The transient current calculations may then be used to improve the design and safety of the battery cell.
FIG. 1 schematically illustrates a powertrain 10 for an electrified vehicle 12 , such as a HEV. Although depicted as a HEV, it should be understood that the concepts described herein are not limited to HEV's and could extend to other electrified vehicles, including but not limited to, PHEV's, BEV's, and fuel cell vehicles.
In one embodiment, the powertrain 10 is a power split system that employs a first drive system that includes a combination of an engine 14 and a generator 16 (i.e., a first electric machine) and a second drive system that includes at least a motor 36 (i.e., a second electric machine), the generator 16 and a battery 50 . For example, the motor 36 , the generator 16 and the battery 50 may make up an electric drive system 25 of the powertrain 10 . The first and second drive systems generate torque to drive one or more sets of vehicle drive wheels 30 of the electrified vehicle 12 .
The engine 14 , such as an internal combustion engine, and the generator 16 may be connected through a power transfer unit 18 . In one non-limiting embodiment, the power transfer unit 18 is a planetary gear set. Of course, other types of power transfer units, including other gear sets and transmissions, may be used to connect the engine 14 to the generator 16 . The power transfer unit 18 may include a ring gear 20 , a sun gear 22 and a carrier assembly 24 . The generator 16 is driven by the power transfer unit 18 when acting as a generator to convert kinetic energy to electrical energy. The generator 16 can alternatively function as a motor to convert electrical energy into kinetic energy, thereby outputting torque to a shaft 26 connected to the carrier assembly 24 of the power transfer unit 18 . Because the generator 16 is operatively connected to the engine 14 , the speed of the engine 14 can be controlled by the generator 16 .
The ring gear 20 of the power transfer unit 18 may be connected to a shaft 28 that is connected to vehicle drive wheels 30 through a second power transfer unit 32 . The second power transfer unit 32 may include a gear set having a plurality of gears 34 A, 34 B, 34 C, 34 D, 34 E, and 34 F. Other power transfer units may also be suitable. The gears 34 A- 34 F transfer torque from the engine 14 to a differential 38 to provide traction to the vehicle drive wheels 30 . The differential 38 may include a plurality of gears that enable the transfer of torque to the vehicle drive wheels 30 . The second power transfer unit 32 is mechanically coupled to an axle 40 through the differential 38 to distribute torque to the vehicle drive wheels 30 .
The motor 36 can also be employed to drive the vehicle drive wheels 30 by outputting torque to a shaft 46 that is also connected to the second power transfer unit 32 . In one embodiment, the motor 36 and the generator 16 are part of a regenerative braking system in which both the motor 36 and the generator 16 can be employed as motors to output torque. For example, the motor 36 and the generator 16 can each output electrical power to a high voltage bus 48 and the battery 50 .
The battery 50 may be a high voltage battery made up of one or more battery cells that are capable of outputting electrical power to operate the motor 36 and the generator 16 . Other types of energy storage devices and/or output devices can also be incorporated for use with the electrified vehicle 12 .
The motor 36 , the generator 16 , the power transfer unit 18 , and the power transfer unit 32 may generally be referred to as a transaxle 42 , or transmission, of the electrified vehicle 12 . Thus, when a driver selects a particular shift position, the transaxle 42 is appropriately controlled to provide the corresponding gear for advancing the electrified vehicle 12 by providing traction to the vehicle drive wheels 30 .
The powertrain 10 may additionally include a control system 44 for monitoring and/or controlling various aspects of the electrified vehicle 12 . For example, the control system 44 may communicate with the electric drive system 25 , the power transfer units 18 , 32 or other components to monitor and/or control the electrified vehicle 12 . The control system 44 includes electronics and/or software to perform the necessary control functions for operating the electrified vehicle 12 . In one embodiment, the control system 44 is a combination vehicle system controller and powertrain control module (VSC/PCM). Although it is shown as a single hardware device, the control system 44 may include multiple controllers in the form of multiple hardware devices, or multiple software controllers within one or more hardware devices.
A controller area network (CAN) 52 allows the control system 44 to communicate with the transaxle 42 . For example, the control system 44 may receive signals from the transaxle 42 to indicate whether a transition between shift positions is occurring. The control system 44 could also communicate with a battery control module of the battery 50 , or other control devices.
Additionally, the electric drive system 25 may include one or more controllers 54 , such as an inverter system controller (ISC). The controller 54 is configured to control specific components within the transaxle 42 , such as the generator 16 and/or the motor 36 , such as for supporting bidirectional power flow. In one embodiment, the controller 54 is an inverter system controller combined with a variable voltage converter (ISC/VVC).
FIG. 2 illustrates a battery testing system 60 for testing and evaluating a battery cell 62 . For example, as is discussed in greater detail below, the battery testing system 60 may be used to detect an internal short circuit (and associated short circuit current flow) of the battery cell 62 in order to evaluate the safety and design of the battery cell 62 .
The battery cell 62 could be part of the battery 50 of the electrified vehicle 12 described with respect to FIG. 1 . However, the battery testing system 60 may be utilized to evaluate other battery cells, for any application, within the scope of this disclosure.
In one embodiment, the battery cell 62 includes a cell body 64 having opposing faces 65 . The opposing faces 65 extend between a positive terminal 66 and a negative terminal 68 of the battery cell 62 . Although shown as a prismatic cell, the battery cell 62 could be any type of cell including but not limited to laminate pouch, prismatic metal can or cylindrical can.
A penetrating device 70 of the battery testing system 60 may be used to penetrate the cell body 64 of the battery cell 62 in order to create a short circuit between the positive terminal 66 and the negative terminal 68 . In one embodiment, the penetrating device 70 is a nail. Other devices could potentially be used to penetrate the cell body 64 of the battery cell 62 , and these devices could include any size, shape, material and configuration. In one embodiment, the battery cell 62 is fully charged prior to performing a battery penetration test with the battery testing system 60 . However, the test can be performed at any state of charge, and can be used to explore changing abuse tolerance properties as a function of state of charge.
In one embodiment, the penetrating device 70 is configured to create a puncture 84 through one or both of the opposing faces 65 in order to simulate an internal shorting condition of the battery cell 62 . For example, the penetrating device 70 may include a pointed tip 89 for penetrating or puncturing the battery cell 62 .
The penetrating device 70 may be moved by a tool 72 between a first position X and a second position X′ (shown in phantom) in order to penetrate the battery cell 62 . For example, in the first position X the penetrating device 70 is spaced away from the battery cell 62 , and in the second position X′ the penetrating device 70 is moved to a position in which the penetrating device 70 has punctured through at least one of the opposing faces 65 of the battery cell 62 .
The tool 72 may move the penetrating device 70 linearly between the first position X and the second position X′, in one embodiment. The tool 72 can be actuated to control various parameters of the battery penetration test, including the speed at which the penetrating device 70 is moved to puncture the battery cell 62 . In one non-limiting embodiment, the tool 72 moves the penetrating device 70 at a speed of 80 mm/second during the battery penetration test. Other testing parameters are contemplated as within the scope of this disclosure, including other testing speeds. For example, slower testing speeds may provide higher quality data.
An impedance meter 74 may be electrically connected to the penetrating device 70 and one or both of the positive terminal 66 and negative terminal 68 of the battery cell 62 . The impedance meter 74 is a diagnostic tool operable to measure impedance and voltage data between the penetrating device 70 and the battery cell 62 . In one non-limiting embodiment, the impedance meter 74 is a commercially available product that operates at a certain frequency (i.e., 1 kHz, 10 kHz, etc.). However, other impedance measuring devices may also be utilized within the scope of this disclosure.
In one embodiment, the impedance meter 74 is connected to the positive terminal 66 of the battery cell 62 via a first electrode 86 and to the penetrating device 70 via a second electrode 88 (see FIG. 2 ). In another embodiment, the impedance meter 74 is connected to the negative terminal 68 of the battery cell 62 (see FIG. 3 ) with the first electrode 86 and to the penetrating device 70 via the second electrode 88 . In other words, the impedance data may be collected between the penetrating device 70 and either the positive terminal 66 or the negative terminal 68 of the battery cell 62 .
The battery testing system 60 may also employ a voltage meter 76 . The voltage meter 76 may be utilized to measure voltage data across the positive terminal 66 and the negative terminal 68 of the battery cell 62 .
Optionally, the battery testing system 60 may also include a temperature sensor 78 for measuring a temperature associated with the battery cell 62 . In one non-limiting embodiment, the temperature sensor 78 is positioned near the puncture 84 of the battery cell 62 . However, the temperature sensor 78 may be positioned at other locations within the scope of this disclosure.
In response to the penetrating device 70 creating a short circuit in the battery cells 62 , the battery testing system 60 measures the impedance data, voltage data and/or temperature data using the impedance meter 74 , the voltage meter 76 and, optionally, the temperature sensor 78 , respectively. This data may be communicated to a data acquisition system 82 of the battery testing system 60 . The data acquisition system 82 is configured to receive, store and analyze the impedance data, voltage data and/or temperature data in order to evaluate the design and safety of the battery cell 62 . The data acquisition system 82 may include the necessary hardware and software for converting the impedance data, voltage data and/or temperature data into digital numeric values that can be manipulated by a computer.
For example, in one non-limiting embodiment, the data acquisition system 82 may be utilized to analyze this data in order to calculate the transient current and heat associated with a short circuit of the battery cell 62 responsive to a battery penetration test. This information can then be used by a battery designer to improve the design and safety of the battery cell 62 .
FIG. 4 illustrates another exemplary battery testing system 160 . In this disclosure, like reference numerals designate like elements where appropriate and reference numerals with the addition of 100 or multiples thereof designate modified elements that are understood to incorporate the same features and benefits of the corresponding original elements.
In this embodiment, the battery testing system 160 includes a first impedance meter 74 A and a second impedance meter 74 B. The first impedance meter 74 A is electrically connected to the positive terminal 66 of a battery cell 62 , and the second impedance meter 74 B is electrically connected to the negative terminal 68 of the battery cell 62 . In this way, two sets of impedance data may be collected simultaneously in response to creating a short circuit in the battery cell 62 with a penetrating device 70 .
FIG. 5 illustrates yet another battery testing system 260 . In this embodiment, the battery testing system 260 incorporates a third impedance meter 74 C in addition to the first impedance meter 74 A and the second impedance meter 74 B. In one embodiment, the third impedance meter 74 C measures impedance data across the positive terminal 66 and negative terminal 68 of the battery cell 62 . In this way, three sets of impedance data may be collected simultaneously (i.e., positive terminal, negative terminal, whole cell). In general, a more accurate analysis of the safety and design of the battery cell 62 may be completed by collecting a greater amount of impedance data.
FIG. 6 illustrates a penetrating device 170 that may be used with any of the battery testing systems 60 , 160 , 260 described above. In this embodiment, the penetrating device 170 includes a first portion 90 and a second portion 92 . The second portion 92 includes a pointed tip 189 , in one embodiment. The pointed tip 189 enables the penetrating device 170 to more easily penetrate a battery cell during a battery penetration test. The pointed tip 189 may be sharp or rounded within the scope of this disclosure.
In one embodiment, the first portion 90 may be coated with an anti-conductive coating 94 . In one non-limiting embodiment, the anti-conductive coating 94 includes plastic, although other non-conductive materials are also contemplated herein. In contrast, the second portion 92 excludes any anti-conductive coating. In other words, the first portion 90 is coated or otherwise modified to restrict the conductive portion of the penetrating device 170 to only those portions that are not coated by the anti-conductive coating 94 . This significantly minimizes any non-idealities associated with introducing a conductive path from a battery cell and is expected to more closely approximate cell behavior during a true internal short circuit.
Although the different non-limiting embodiments are illustrated as having specific components or steps, the embodiments of this disclosure are not limited to those particular combinations. It is possible to use some of the components or features from any of the non-limiting embodiments in combination with features or components from any of the other non-limiting embodiments.
It should be understood that like reference numerals identify corresponding or similar elements throughout the several drawings. It should be understood that although a particular component arrangement is disclosed and illustrated in these exemplary embodiments, other arrangements could also benefit from the teachings of this disclosure.
The foregoing description shall be interpreted as illustrative and not in any limiting sense. A worker of ordinary skill in the art would understand that certain modifications could come within the scope of this disclosure. For these reasons, the following claims should be studied to determine the true scope and content of this disclosure. | A battery testing system according to an exemplary aspect of the present disclosure includes, among other things, a penetrating device and an impedance meter electrically connected to the penetrating device. | 6 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a radiator system, a radiating method and a thermal buffer which relieve thermal stresses generating when heat is transmitted from high-temperature bodies to receivers. Thus, it is possible for the radiator system, radiating method and thermal buffer to secure stable boardability for the high-temperature bodies and receivers. Moreover, the present invention relates to semiconductor modules, heat spreaders and substrates, application forms of the radiator system, radiating method and thermal buffer.
[0003] 2. Description of the Related Art
[0004] Many component parts are heated to high temperatures in service. From the viewpoint of the heat resistance, it is necessary to properly radiate component parts. In particular, electric appliances and electronic appliances comprise devices whose service temperature ranges are regulated strictly. Accordingly, in the electric appliances and electronic appliances, it is important to radiate the devices. Hereinafter, the radiation will be described with reference to an example, a semiconductor module in which semiconductor devices are disposed on a substrate.
[0005] Depending on usage of semiconductor modules, semiconductor devices usually generate heat to exhibit high temperatures. In order to ensure that semiconductor devices operate stably, it is indispensable to efficiently radiate them.
[0006] Conventionally, heat generated by semiconductor devices have been radiated by boarding semiconductor devices on substrates with high thermal conductivity and disposing heatsinks on the substrates. The more semiconductors are downsized, the higher they are integrated, moreover, the greater the magnitude of currents flowing in semiconductor devices, the more such radiation becomes important.
[0007] By the way, semiconductor devices comprise Si, they exhibit such a small linear expansion coefficient as a few ppm's/° C. On the other hand, when substrates on which the semiconductors are boarded are examined for metals, such as Cu, being present in the surface, they exhibit such a large linear expansion coefficient as over 10 ppm/° C. Consequently, when the semiconductor devices and substrates are bonded directly by solder, there might occur such failures that the semiconductor devices are come off from the substrates due to the difference between the linear expansion coefficients.
[0008] In order to secure the thermal transmissibility (or radiating property) from semiconductor devices to substrates and the stable boardability (or bondability) of semiconductor devices with respect to substrates, heat spreaders with high thermal conductivity as well as low expandability are proposed to interpose them between the semiconductors and substrates. For example, Japanese Unexamined Patent Publication (KOKAI) No. 2000-77,582 and Japanese Unexamined Utility Model Publication (KOKAI) No. 63-20,448 disclose the heat spreaders. The former publication discloses a heat spreader which comprises a core composed of Cu with high thermal conductivity and disposed at the middle, and a frame composed of an invar alloy with low expandability and surrounding the outer periphery of the core. The latter publication discloses a heat spreader in which an invar alloy with low expandability is surrounded by Cu with high thermal conductivity, contrary to the former publication.
[0009] In Japanese Unexamined Patent Publication (KOKAI) No. 2000-77,582, the frame (i.e., invar alloy) inhibits the core (i.e., Cu) from thermally expanding. As a result, there might occur that the bonding surfaces of the core which are bonded to the semiconductor devices and substrate swell in the vertical directions. Consequently, the heat spreader might not be able to secure the adhesiveness between the semiconductor device and substrate. Eventually, there might occur such failures that the semiconductor devices are come off from the substrates.
[0010] It seems that the heat spreader disclosed in Japanese Unexamined Utility Model Publication (KOKAI) No. 63-20,448 does not suffer from the disadvantage, and that it is good in terms of the thermal conductivity, thermal diffusion effect and bondability. Regardless of the performance of the heat spreader per se, when the heat spreader disclosed in the publication is observed regarding the bonding relationship between the heat spreaders, semiconductor devices and substrate, it is understood that the opposite surfaces of the heat spreaders are bonded to the semiconductor devices and substrate in the same manner. Specifically, the bonding area between the semiconductor devices and heat spreaders little differs from the bonding area between the substrate and heat spreaders.
[0011] However, when considering the fact that the linear expansion coefficient of semiconductor devices differs from that of substrates inherently, it cannot necessarily say with any finality that it is reasonable to bond heat spreaders to semiconductor devices as well as to substrates in the same manner, from the viewpoint of the boardability of semiconductor devices with respect to substrates.
SUMMARY OF THE INVENTION
[0012] The present invention has been developed in view of such circumstances. It is therefore an object of the present invention to provide a radiator system, a radiating method and a thermal buffer which can secure the bondability (or boardability) between semiconductor modules, but not limited to the case, and further extensively to the case between high-temperature bodies and receivers which receive heat from the high-temperature bodies. Moreover, it is a further object of the present invention to provide semiconductor modules, heat spreaders and substrates which utilize the radiator system, radiating method and thermal buffer.
[0013] The inventors of the present invention have studied wholeheartedly in order to solve the problems. As a result of trial and error over and over again, they thought of varying the above-described bonding areas of heat spreaders, for example, between the device-side bonding area and substrate-side bonding area. They further developed the novel idea to arrive at completing the present invention.
[0014] (Radiator System)
[0015] A radiator system according to the present invention comprises: a high-temperature body being a thermal source; a receiver with the high-temperature body boarded thereon, the receiver receiving heat from the high-temperature body; and a thermal buffer interposed at least between the high-temperature body and the receiver to buffer thermal transmission from the high-temperature body to the receiver; whereby the heat from the high-temperature body is radiated by the receiver or is radiated by way of the receiver;
[0016] wherein the thermal buffer comprises a high thermal conductor, and a low expander disposed at a position facing the high-temperature body and buried in the high thermal conductor; and the thermal buffer has a first bonding area (or high-temperature body-side bonding area) with respect to the high-temperature body, and a second bonding area (or receiver-side bonding area) with respect to the receiver, the second bonding area being enlarged greater than the first bonding area. Especially, the second bonding area can preferably be enlarged greater than the first bonding area in the following manner. For example, in the cross-section of the thermal buffer, the angle formed by a diagonal line, which connects an end of the first bonding area with an end of the second bonding area, and a vertical line, which extends vertically from the end of the first bonding area to the second bonding area, can preferably be 45 deg. or more as illustrated in FIG. 9.
[0017] Hereinafter, when the high-temperature body, the receiver and the thermal buffer are considered a semiconductor device, a substrate and a heat spreader, respectively, it is possible to grasp the present radiator system as a semiconductor module. For example, the present invention can be regarded as a semiconductor module, comprising: a semiconductor device being a thermal source; a substrate with the semiconductor device boarded thereon; and a heat spreader interposed between the semiconductor device and the substrate to diffuse heat from the semiconductor device to the substrate;
[0018] wherein the heat spreader comprises a high thermal conductor, and a low expander disposed at a position facing the semiconductor device and buried in the high thermal conductor; and the heat spreader has a first bonding area (or device-side bonding area) between the heat spreader and the semiconductor device and with respect to the semiconductor device, and a second bonding area (or substrate-side bonding area) between the heat spreader and the substrate and with respect to the substrate, the second bonding area being enlarged greater than the first bonding area.
[0019] Moreover, when the high-temperature body, the receiver and the thermal buffer are considered a semiconductor device, a heatsink and a substrate, respectively, it is possible to grasp the present radiator system as a semiconductor module. For instance, the present invention can be regarded as a semiconductor module, comprising: a semiconductor device being a thermal source; a heatsink receiving heat from the semiconductor; and a substrate having opposite surfaces, bonded to the semiconductor device on one of the opposite surfaces, and bonded to the heatsink on the other one of the opposite surfaces to transmit the heat from the semiconductor device to the heatsink;
[0020] wherein the substrate comprises a high thermal conductor, and a low expander disposed at a position facing the semiconductor device and buried in the high thermal conductor; and the substrate has a first bonding area (or device-side bonding area) between the substrate and the semiconductor device and with respect to the semiconductor device, and a second bonding area (or heatsink-side bonding area) between the substrate and the heatsink and with respect to the heatsink, the second bonding area being enlarged greater than the first bonding area.
[0021] In addition, when the high-temperature body, the receiver and the thermal buffer are considered a substrate, a heatsink and a heat spreader, respectively, it is possible to grasp the present radiator system as a semiconductor module. For example, the present invention can be regarded as a semiconductor module, comprising: a substrate being a thermal source; a heatsink receiving heat from the substrate; and a heat spreader having opposite surfaces, bonded to the substrate on one of the opposite surfaces, and bonded to the heatsink on the other one of the opposite surfaces to transmit the heat from the substrate to the heatsink;
[0022] wherein the heat spreader comprises a high thermal conductor, and a low expander disposed at a position facing the substrate and buried in the high thermal conductor; and the heat spreader has a first bonding area (or substrate-side bonding area) between the heat spreader and the substrate and with respect to the substrate, and a second bonding area (or heatsink-side bonding area) between the heat spreader and the heatsink and with respect to the heatsink, the second bonding area being enlarged greater than the first bonding area.
[0023] (Radiating Method)
[0024] Not limited to the above-described present radiator system, it is possible to grasp the present invention as a radiating method. For instance, the present invention can be regarded as a radiating method for radiating heat from a high-temperature body being a thermal source by a receiver with the high-temperature body boarded thereon, the receiver receiving the heat from the high-temperature body, or radiating the heat by way of the receiver, the radiating method comprising the step of: preparing a thermal buffer interposed at least between the high-temperature body and the receiver to buffer thermal transmission from the high-temperature body to the receiver, wherein the thermal buffer comprises a high thermal conductor, and a low expander disposed at a position facing the high-temperature body and buried in the high thermal conductor; and the thermal buffer has a first bonding area (or high-temperature body-side bonding area) with respect to the high-temperature body, and a second bonding area (or receiver-side bonding area) with respect to the receiver, the second bonding area being enlarged greater than the first bonding area.
[0025] (Thermal Buffer)
[0026] Further, not limited to the above-described present radiator system, it is possible to grasp the present invention as a thermal buffer. For example, the present invention can be regarded as a thermal buffer interposed at least between a high-temperature body being a thermal source and a receiver with the high-temperature body boarded thereon, the receiver receiving heat from the high-temperature body, to buffer thermal transmission from the high-temperature body to the receiver,
[0027] wherein the thermal buffer comprises a high thermal conductor, and a low expander disposed at a position facing the high-temperature body and buried in the high thermal conductor; and the thermal buffer has a first bonding area (or high-temperature body-side bonding area) positioned with respect to the high-temperature body, and a second bonding area (or receiver-side bonding area) positioned with respect to the receiver, the second bonding area being enlarged greater than the first bonding area.
[0028] Hereinafter, when the high-temperature body and the receiver are considered a semiconductor device and a substrate, respectively, it is possible to grasp the above-described present thermal buffer as a heat spreader. For instance, the present invention can be regarded as a heat spreader interposed between a semiconductor device being a thermal source and a substrate with the semiconductor device boarded thereon to diffuse heat from the semiconductor device to the substrate,
[0029] wherein the heat spreader comprises a high thermal conductor, and a low expander disposed at a position facing the semiconductor device and buried in the high thermal conductor; and the heat spreader has a first bonding area (or device-side bonding area) between the heat spreader and the semiconductor device and with respect to the semiconductor device, and a second bonding area (or substrate-side bonding area) between the heat spreader and the substrate and with respect to the substrate, the second bonding area being enlarged greater than the first bonding area.
[0030] Furthermore, when the high-temperature body and the receiver are considered a semiconductor device and a heatsink, respectively, it is possible to grasp the above-described present thermal buffer as a substrate. For example, the present invention can be regarded as a substrate having opposite surfaces, bonded to a semiconductor device being a thermal source on one of the opposite surfaces, and bonded to a heatsink receiving heat from the semiconductor device on the other one of the opposite surfaces to transmit the heat from the semiconductor device to the heatsink,
[0031] wherein the substrate comprises a high thermal conductor, and a low expander disposed at a position facing the semiconductor device and buried in the high thermal conductor; and the substrate has a first bonding area (or a device-side bonding area) between the substrate and the semiconductor device and with respect to the semiconductor device, and a second bonding area (heatsink-side bonding area) between the substrate and the heatsink and with respect to the heatsink, the second bonding area being enlarged greater than the first bonding area.
[0032] Moreover, when the high-temperature body and the receiver are considered a substrate and a heatsink, respectively, it is possible to grasp the above-described present thermal buffer as a heat spreader. For instance, the present invention can be regarded as a heat spreader having opposite surfaces, bonded to a substrate being a thermal source on one of the opposite surfaces, and bonded to a heatsink receiving heat from the substrate on the other one of the opposite surfaces to transmit the heat from the substrate to the heatsink,
[0033] wherein the heat spreader comprises a high thermal conductor, and a low expander disposed at a position facing the semiconductor device and buried in the high thermal conductor; and the heat spreader has a first bonding area (or substrate-side bonding area) between the heat spreader and the substrate and with respect to the substrate, and a second bonding area (or heatsink-side bonding area) between the heat spreader and the heatsink and with respect to the heatsink, the second bonding area being enlarged greater than the first bonding area.
[0034] Note that the above-described heat spreader according to the present invention can take on not only a simple thermal diffusing function but also the functions of heatsink. Further, wherever appropriate, a heat spreader interposed between a semiconductor device and a substrate will be hereinafter referred to as a device-side heat spreader, and a heat spreader interposed between a substrate and a heatsink will be hereinafter referred to as a substrate-side heat spreader. Furthermore, a heatsink can be simple metallic plates whose major component is Cu or Al. The heatsink can constitute the entire enclosure of semiconductor modules or a part of the enclosure as well. Moreover, it is possible to use liquid-cooled heatsinks in which a coolant (e.g., cooling water) is held or flowed to enhance the cooling efficiency.
[0035] In addition, the wording, such as “boarded,” is used in the present specification. Note that, however, the wording does not directly restrain the positional relationships between the high-temperature body and receiver, and the like. For example, it does not matter whether the high-temperature body and receiver are disposed in a vertical manner, a horizontal manner, and so forth. Still further, intervening objects can be present between the high-temperature body and receiver.
[0036] The above-described semiconductor modules are some examples which further embody the present invention. Specifically, the semiconductor modules are exemplified in which either one of the heat spreader and substrate is used as the thermal buffer. However, it is possible to constitute semiconductor modules, and the like, by properly applying the present thermal buffer to a plurality of component members, such as the device-side heat spreader, substrate and substrate-side heat spreader.
[0037] Hereinafter, the operations and advantages of the present invention will be described more specifically while exemplifying a semiconductor in which the present thermal buffer is used as a heat spreader. In the present semiconductor module, not limited to the heat spreader in which the low expander is buried in the high thermal conductor is used, the respective bonding areas between the heat spreader and semiconductor module as well as between the heat spreader and substrate are arranged appropriately. Accordingly, while securing the thermal diffusion property and radiation property, it is also possible to secure the more stable boardability of the semiconductor device with respect to the substrate. Specifically, as described above, the substrate-side bonding area (or second bonding area) is enlarged greater than the device-side bonding area (or first bonding area). It is not necessarily definite why the arrangement further stabilizes the boardability of the semiconductor device with respect to the substrate. However, it is believed as follows. Here, in order to simplify the explanation, the case in which the low expander is buried in the middle of the high thermal conductor in the vertical cross-section will be described in an exemplifying manner.
[0038] The linear expansion coefficient of semiconductor devices is small generally, and the thermal expansion magnitude is also small. On the other hand, substrates with semiconductors boarded thereon comprise metals, such as Cu, adjacent to the surface at least, and the linear expansion coefficient is great, and accordingly the thermal expansion magnitude is also great. Based on these facts, it is ideal that heat spreaders exhibit a thermal expansion magnitude close to that of semiconductor devices on the device-side bonding surface, and exhibit a thermal expansion magnitude close to that of substrates on the substrate-side bonding surface, because heat spreaders interposed between them absorb and relieve the linear thermal expansion difference between them. Namely, it is required that the thermal expansion magnitude be less comparatively on the device-side bonding surface of heat spreaders, and the thermal expansion magnitude be great comparatively on the substrate-side bonding surface of heat spreaders.
[0039] Next, let us consider the case in which semiconductor devices are heated to high temperatures by using semiconductor modules and the temperature of heat spreaders enters the stable period from the transitional period. In other words, let us consider the case in which heat spreaders show a substantially uniform temperature as a whole. In this instance, when heat spreaders are observed independently, it seems that the overall thermal expansion magnitude is substantially equal on the device-side bonding surface as well as on the substrate-side bonding surface, as far as the low expander is buried in the middle of the high thermal conductor. However, when the distribution of local thermal expansion magnitudes is observed, the thermal expansion magnitude of heat spreaders should be reduced in the vicinity of the low expander due to the restraint by the low expander. Hence, like the present semiconductor modules, when semiconductor devices are bonded to the local area of heat spreaders where the thermal expansion magnitude is reduced due to the restraint by the low expander, it is possible to reduce the thermal expansion difference between the heat spreaders and semiconductor devices. On the contrary, let us observe heat spreaders as a whole, when substrates are bonded to the wide area of heat spreaders where heat spreaders exhibit an enlarged thermal expansion magnitude, it is possible to reduce the thermal expansion difference at the bonding surface between the heat spreaders and substrates as well.
[0040] The semiconductor module which uses the present thermal buffer as the heat spreader has been described so far. However, it is possible to believe that a semiconductor module which uses the present thermal buffer as the substrate operates and effects advantages in the same manner. Moreover, not limited to semiconductor modules, the situations are similarly applicable to three-layered structures which comprise a high-temperature body, a receiver and a thermal buffer interposed between the high-temperature body and receiver. In addition, the case where the low expander is buried in the middle of the high thermal conductor is exemplified to describe the present invention. However, it is natural that the present invention is not limited to the arrangement. For example, the closer the low expander is disposed with respect to the high-temperature body (e.g., semiconductor devices), the more the thermal expansion differences between the high-temperature body and thermal buffer (e.g., heat spreaders or substrates) and between the thermal buffer and receiver (e.g., substrates or heatsinks) are diminished.
[0041] As far as the lower expander is disposed at a position facing the high-temperature body, it can be the same size (or breadth) as the bonding surface of the high-temperature body, or it can have sizes which differ therefrom. Moreover, the one and only low expander can be buried in the high thermal conductor, or can be divided into pieces and be buried therein. In addition, it is possible to control the thermal expansion magnitude of the thermal buffer not only by adjusting the disposition of the low expander in the thermal buffer, but also by adjusting the volumetric occupying proportion of the low expander therein. For example, when the volumetric occupying proportion of the low expander is enlarged, it is possible to reduce the thermal expansion magnitude of the entire thermal buffer. When the disposition or volumetric occupying proportion of the low expander in the thermal buffer is thus adjusted, it is possible to more efficiently relieve the thermal expansion difference at the bonding surface between the high-temperature body and receiver.
[0042] Indeed, it is needless to say that it is important that the thermal buffer is good in terms of the thermal conductivity, because the thermal buffer diffuses or radiates the heat from the high-temperature body to the receiver effectively. The high thermal conductor in which the low expander is buried is in charge of the function. Hence, it is suitable that the thermal buffer can comprise the high thermal conductor, and the low expander which is buried in the high thermal conductor and whose outer peripheral surface is surrounded by the high thermal conductor. This because, although the low expander is generally poor in terms of the thermal conductivity, the high thermal conductor provides a great thermal path when the high thermal conductor surrounds the low expander. Not that it is not necessarily required that the high thermal conductor surround the entire outer surface of the low expander completely. For instance, it is acceptable even if the end surfaces of the low expander are not surrounded by the high thermal conductor.
[0043] By the way, the low expander according to the present invention can be satisfactory as far as it exhibits a linear expansion coefficient smaller than that of the high thermal conductor. Indeed, in order to further enlarge the degree of freedom in designing the thermal buffer, it is suitable that the low expander can comprise a material whose linear expansion coefficient is smaller than that of the high-temperature body. This is because, with the arrangement, it is possible to relieve the thermal expansion difference between the high-temperature body and receiver more effectively when the disposition, configuration and volumetric occupying proportion of the low expander are adjusted properly. As for such a material for the low expander, an invar alloy is suitable, for example. This is because an invar alloy is less expensive and is good in terms of the formability. Note that, as an invar alloy, there are many invar alloys such as ferromagnetic invar alloys, Fe-based amorphous invar alloys and Fe—Ni-based antiferromagnetic invar alloys in which Cr substitutes for a part of Ni. Taking the service temperature range, processability, cost, being magnetic or nonmagnetic into consideration, it is possible to select invar alloys which are appropriate for the usage of semiconductor modules. Accordingly, in the present invention, the type and composition of invar alloys are not limited in particular. When naming some of the examples, it is possible to use the well-known ferromagnetic invar alloys such as Fe-36% Ni (the unit being % by mass, being the same hereinafter) and Fe-31%-5% Co, a super invar alloy.
[0044] The high thermal conductor in which the low expander is buried can be satisfactory, as far as it is better than the low expander in terms of the thermal conductivity. Indeed, in order to assure the good thermal diffusing property as the thermal buffer (as the heat spreaders or substrates in particular), moreover, in view of being less expensive and exhibiting good formability, the high thermal conductor can preferably comprise a pure metal or alloy whose major component is Cu or Al.
[0045] Note that the better the receiver is in terms of the thermal conductivity, the more it can be satisfactory. However, it does not matter what sort of materials the receiver is made from. Moreover, the receiver can comprise materials whose thermal expansion magnitude is great. This is because it is possible to comparatively enlarge the thermal expansion magnitude on the receiver-side bonding surface of the thermal buffer according to the present invention. Therefore, the receiver can be satisfactory when it comprises a metallic body with a metallic material base. For instance, in accordance with the present invention, it is possible to utilize not only copper-lined ceramic substrates whose thermal expansion magnitude is less, but also metallic substrates whose thermal expansion magnitude is great, for substrates with semiconductors boarded. Note that metallic substrates are advantageous for reducing the cost of semiconductor modules because metallic substrates are less expensive compared with ceramic substrates.
BRIEF DESCRIPTION OF THE DRAWINGS
[0046] A more complete appreciation of the present invention and many of its advantages will be readily obtained as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings and detailed specification, all of which forms a part of the disclosure:
[0047] [0047]FIG. 1 is a major vertical cross-sectional view for illustrating a power module according to Example No. 1 of the present invention;
[0048] [0048]FIG. 2 is a major vertical cross-sectional view for illustrating a power module according to Example No. 2 of the present invention;
[0049] [0049]FIG. 3 is a major vertical cross-sectional view for illustrating a power module according to Example No. 3 of the present invention;
[0050] [0050]FIG. 4 is a major vertical cross-sectional view for illustrating a power module according to Example No. 4 of the present invention;
[0051] [0051]FIG. 5 is a major vertical cross-sectional view for illustrating a power module according to Example No. 5 of the present invention;
[0052] [0052]FIG. 6 is a major vertical cross-sectional view for illustrating a power module according to Example No. 6 of the present invention;
[0053] [0053]FIG. 7 is a major horizontal cross-sectional view for illustrating a heat spreader according Example No. 1 of the present invention;
[0054] [0054]FIG. 8 is a major horizontal cross-sectional view for illustrating a power module according to Example No. 7 of the present invention; and
[0055] [0055]FIG. 9 is a schematic cross-sectional view for illustrating the areal relationship between a first bonding area and a second bonding area.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0056] Having generally described the present invention, a further understanding can be obtained by reference to the specific preferred embodiments which are provided herein for the purpose of illustration only and not intended to limit the scope of the appended claims.
EXAMPLE
[0057] Hereinafter, the present invention will be described more specifically with reference to specific examples according to semiconductor modules, an example of the present radiator system.
Example No. 1
[0058] [0058]FIG. 1 illustrates a major vertical cross-section of a power module 100 (i.e., semiconductor module) according to Example No. 1 of the present invention. The power module 100 can be used, for example, in inverters for controlling the operations of three-phase induction motors.
[0059] The power module 100 comprises semiconductor devices 10 , a metallic substrate 20 , and heat spreaders 30 . The semiconductor devices 10 can be a variety of semiconductor devices such as power MOSFET (i.e., metal-oxide semiconductor field-effect transistors). The semiconductor devices 10 are boarded on the metallic substrate 20 which is made of copper. The heat spreaders 30 are interposed between the semiconductor devices 10 and metallic substrate 20 . For convenience, FIG. 1 illustrates the vicinity of one of the semiconductor devices 10 only.
[0060] The bonding (i.e., device-side bonding) between the semiconductor devices 10 and heat spreaders 30 is done by solder 41 . The bonding (i.e., substrate-side bonding) between the metallic substrate 20 and heat spreaders 30 is done by solder 42 . Note that it is possible to carry out bonding by the solder 41 and solder 42 simultaneously as done in brazing. In this Example No. 1, however, the substrate-side bonding is done firs by the solder 42 having a high melting point. Thereafter, the device-side bonding is done by the solder 41 having a low melting point.
[0061] The heat spreaders 30 comprise a cladding material. The cladding material comprises a high thermal conductor 31 , and a low expander 32 surrounded by the high thermal conductor 31 . The high thermal conductor 31 is composed of Cu. The low expander 32 is disposed in the middle of the heat spreaders 30 , and is composed of an Fe-36% Ni invar alloy. Therefore, as illustrated in FIG. 1, the heat spreaders 30 are formed as a three-layered construction in the vertical direction as well.
[0062] For instance, in Example No. 1, the overall thickness of the heat spreaders 30 was about 1 mm. In the heat spreaders 30 , the thickness of the invar alloy was controlled to ⅓ of the overall thickness of the heat spreaders 30 , and was accordingly about 0.3 mm. Moreover, the overall width of the heat spreaders 30 was 12 mm, and the width of the invar alloy was 7 mm. The linear expansion coefficients of the heat spreaders 30 were found as follows. At portions immediately above the invar alloy as well as at portions immediately below the invar alloy similarly, the linear expansion coefficient was 10.5 ppm/° C. On the other hand, the heat spreaders 30 which included Cu disposed around the invar alloy as well exhibited an overall linear expansion coefficient of 13.3 ppm/° C. For reference, the linear expansion coefficient of the semiconductor devices 10 was about 4 ppm/° C., and the linear expansion coefficient of the metallic substrate 20 was about 17 ppm/° C.
[0063] In Example No. 1, the heat spreaders 30 are bonded with the semiconductor devices 10 at the areas (i.e., device-side bonding surfaces F 1 ) where the linear expansion coefficient is reduced locally. Moreover, when the heat spreaders 30 are bonded with the metallic substrate 20 , the areas (i.e., substrate-side bonding areas F 2 ) are utilized where the liner expansion coefficient is enlarged. The arrangement corresponds to disposing the low expanders 32 at positions facing the semiconductor devices 10 and enlarging the substrate-side bonding areas greater than the device-side bonding areas in accordance with the present invention.
[0064] It is apparent from Example No. 1 that it is possible to obtain linear expansion coefficients much closer to the linear expansion coefficients, exhibited by the mating members to be bonded therewith, at the respective bonding surfaces even when the heat spreaders 30 are formed as a symmetrical construction vertically as well as horizontally. As a result, the thermal expansion difference between the semiconductor devices 10 and metallic substrate 20 can be relieved more effectively. Specifically, the semiconductor devices 10 and heat spreaders 30 can be inhibited from coming off from the metallic substrate 20 . Accordingly, it is possible to secure the boarding stability of the semiconductor devices 10 with respect to the metallic substrate 20 on a higher level.
[0065] Note that the heat generated by the semiconductor devices 10 is transmitted to the metallic substrate 20 by way of Cu (i.e., the high thermal conductor 31 ) which is good in terms of the thermal conductivity. Therefore, it is needles to say that the heat spreaders 30 are ensured that they fully produce the thermal diffusion effect.
Example No. 2
[0066] [0066]FIG. 2 illustrates a power module 200 of Example No. 2 according to the present invention. The power module 200 is provided with heat spreaders 230 whose form is varied from that of the heat spreaders 30 in Example No. 1. Note that the like reference numerals designate the same component parts as those of Example No. 1 in the drawing.
[0067] In the heat spreaders 230 , a high thermal conductor 231 is used whose cross-section is formed as a trapezoid, instead of the rectangular parallel piped high thermal conductor 31 used in Example No. 1. When the disposition of Cu whose linear expansion coefficient is great is thus optimized, it is possible to make the linear expansion coefficients at the device-side bonding surfaces F 1 much closer to the linear expansion coefficient of the semiconductor devices 10 .
Example No. 3
[0068] [0068]FIG. 3 illustrates a major vertical cross-section of a power module 300 according to Example No. 3 of the present invention. The power module 300 comprises semiconductor devices 310 , metallic substrates 320 , a housing 350 , and heat spreaders 330 . The substrates 320 are bonded with the semiconductor devices 310 by solder 341 . The substrates 320 are boarded on the housing 350 of the power module 300 . The heat spreaders 330 are interposed between the substrate 320 and housing 350 . For convenience, FIG. 3 illustrates the vicinity of one of the semiconductor devices 310 only. In Example 3 , the housing 350 is made of an Al alloy which is good in terms of the thermal conductivity, and functions as a heatsink as well. Note that the power module 300 is enhanced in terms of the radiating ability when it is provided with air-cooling fins around the outer periphery or a coolant is flowed in it to enhance the cooling efficiency, although the arrangements are not depicted in the drawing. Moreover, the housing 350 made of the Al alloy exhibited a linear expansion coefficient of about 24 ppm/° C.
[0069] The substrates 320 are a ceramic insulation substrate with double-sided copper-lining, respectively. The ceramic insulation substrate comprises a ceramic plate 321 disposed at the center core, and wiring layers 322 , 323 made of copper and disposed on the opposite surfaces of the ceramic plate 321 . In addition to copper, the wiring layers 322 , 323 can be made of aluminum. Such a ceramic insulation substrate is available under trade names such as “DBA (i.e., Direct Brazed Aluminum)” and “DBC (i.e., Direct Bond Copper).” 48
[0070] In the same manner as Example No. 1, the heat spreaders 330 comprise a cladding material. The cladding material comprises a high thermal conductor 331 , and a low expander 332 surrounded by the high thermal conductor 331 . The high thermal conductor 331 is composed of Cu. The low expander 332 is disposed in the middle of the heat spreaders 330 , and is composed of an Fe-36% Ni invar alloy.
[0071] The bonding (i.e., substrate-side bonding) between the heat spreaders 330 and substrates 320 is done by solder 342 . The bonding (i.e., housing-side bonding) between the heat spreaders 330 and housing 350 is done by solder 343 . In Example No. 3 as well, the substrates 320 are disposed at the positions facing the low expanders 332 , and the housing-side bonding areas (or heatsink-side bonding areas) are enlarged greater than the substrate-side bonding areas. Further, also in Example No. 3, the heat spreaders 330 are bonded with the substrates 320 at the areas (i.e., substrate-side bonding surfaces F 1 ) where the linear expansion coefficient is reduced locally. Furthermore, the heat spreaders 330 are bonded with the housing 350 at the areas (i.e., housing-side bonding areas F 2 ) where the linear expansion coefficient is enlarged. As a result, the difference between the linear expansion coefficients is reduced at the bonding surfaces so that the boarding stability of the substrates 320 with respect to the housing 350 is improved. Moreover, similarly to Example No. 1, the heat generated by the substrate 330 is transmitted to the housing 350 by way of Cu (i.e., the high thermal conductor 331 ) which is good in terms of the thermal conductivity, and accordingly the heat spreaders 330 are ensured that they fully produce the thermal diffusion effect.
[0072] In addition, since highly expensive composite materials, such as CuMo and Al/SiC, have been used as heat spreaders conventionally, they have been inhibited the cost of power modules from reducing. On the contrary, since the above-described composite material used in Example No. 3 is less expensive, it makes the cost reduction of power modules easy.
Example No. 4
[0073] [0073]FIG. 4 illustrates a power module 400 of Example No. 4 according to the present invention. The power module 400 is provided with heat spreaders 430 whose form is varied from that of the heat spreaders 30 in Example No. 1. Note that the like reference numerals designate the same component parts as those of Example No. 1 in the drawing.
[0074] In the heat spreaders 430 , the integral low expander 32 is divided equally into two parts, and the resulting divided low expanders 432 , 433 are buried in a high thermal conductor 431 .
[0075] In this Example No. 4, the high thermal conductor 431 is also extended in the vertical direction immediately below the semiconductors 10 . The paths which diffuse the heat generated by the semiconductors 10 to the metallic substrate are increased accordingly by the extension. Therefore, it is possible to more efficiently diffuse and radiate the heat generated by the semiconductors 10 to the metallic substrate 20 .
Example No. 5
[0076] [0076]FIG. 5 illustrates a power module 500 of Example No. 5 according to the present invention. The power module 500 is provided with heat spreaders 530 whose form is varied from that of the heat spreaders 30 in Example No. 1. Note that the like reference numerals designate the same component parts as those of Example No. 1 in the drawing.
[0077] In the heat spreaders 530 , the burying position of the low expander 32 is shifted from the inner middle of a high thermal conductor 531 to the device-side bonding surface F 1 . When the disposition of invar alloys whose linear expansion coefficient is small is thus optimized, it is possible to make the linear expansion coefficient at the device-side bonding surface F 1 much closer to the liner expansion coefficient of the semiconductor devices 10 .
Example No. 6
[0078] [0078]FIG. 6 illustrates a power module 600 of Example No. 6 according to the present invention. The power module 600 is provided with heat spreaders 630 whose form is varied from that of the heat spreaders 30 in Example No. 1. Note that the like reference numerals designate the same component parts as those of Example No. 1 in the drawing.
[0079] In the heat spreaders 630 , the burying position of the low expander 32 is shifted from the inner middle of a high thermal conductor 631 to the substrate-side bonding surface F 2 . In this instance, since the volumetric proportion of the high thermal conductor 631 which is present immediately below the semiconductor devices 10 increases, the heat spreaders 630 are further enhanced in terms of the heat diffusing ability. Namely, the heat spreaders 630 are improved in terms of the thermal conductivity so that the temperature is likely to lower.
[0080] (Others)
[0081] [0081]FIG. 7 illustrates another example, and is a horizontal cross-section of the heat spreaders 30 in the power module 100 of Example No. 1 according to the present invention. Here, in accordance with linear expansion coefficients desired at the device-side bonding surface F 1 , it is possible to determine whether the width W occupied by the low expander 32 in the heat spreaders 30 is wide or narrow with respect to the width of the semiconductor devices 10 to be bonded with the heat spreaders 30 . For example, it is possible to control the width W of the low expander 32 in a range of from −60% to +60% with respect to the width of the semiconductor devices 10 . Indeed, when the low expander 32 is exposed in the device-side bonding surface F 1 as described in Example No. 5, it is needed to narrow the width W of the low expander 32 less than the width of the semiconductor devices 10 .
[0082] So far, like the heat spreaders 30 illustrated in FIG. 7, the descriptions have been given on the low expander 32 whose opposite ends in vertical cross-section are not necessarily surrounded by the high thermal conductor 31 completely. However, like heat spreaders 830 of Example No. 7 according to the present invention illustrated in FIG. 8, it is needless to say that the entire periphery of a low expander 832 can be surrounded by a high thermal conductor 831 completely. It is preferable to employ such a form because the path in which heat diffuses from the semiconductor devices 10 to the metallic substrate 20 can be expanded. As a result, even in above-described Example No. 5, it is not necessarily required to narrow the width of the low expander 832 less than the width of the semiconductor devices 10 .
[0083] Having now fully described the present invention, it will be apparent to one of ordinary skill in the art that many changes and modifications can be made thereto without departing from the spirit or scope of the present invention as set forth herein including the appended claims. | A radiator system includes a high temperature body being a thermal source, a receiver with the high-temperature body boarded thereon, and a thermal buffer. The receiver receives heat from the high-temperature body. The thermal buffer is interposed at least between the high-temperature body and the receiver to buffer thermal transmission from the high-temperature body to the receiver, includes a high thermal conductor and a low expander disposed at a position facing the high-temperature body and buried in the high thermal conductor, and has a first bonding area with respect to the high-temperature body and a second bonding area with respect to the receiver. The second bonding area is enlarged greater than the first bonding area. The heat from the high-temperature body is radiated by the receiver or is radiated by way of the receiver. Thus, the thermal expansion difference can be minimized between the high-temperature body and receiver. | 7 |
This application is a continuation of application Ser. No. 256,194, filed May 23, 1972, now abandoned, which is a continuation of Ser. No. 72,034, filed Sept. 14, 1970.
BACKGROUND OF THE INVENTION
The field of this invention is pressure operated safety valves for disposition in well tubing.
In the past, it has been the practice to use devices in producing wells, particularly offshore wells, which automatically close when the well pressure reaches a predetermined amount for the purpose of preventing well blowouts and the resultant fires and pollution of the seas with oil.
The most common type used has been marketed under the name, "Storm" choke, but it is not as widely used at it should be because it is generally damaged by sand or other abrasives flowing therethrough with the oil during normal production, so that it is not operative for preventing blowouts when they occur.
Ball-type safety valves, examples of which are found in U.S. Pat. No. 2,894,715; U.S. Pat. No. Re. 25,471; U.S. Pat. No. 2,998,070; U.S. Pat. No. 3,035,808; U.S. Pat. No. 3,126,908 and U.S. Pat. No. 3,189,044, have also been used in an attempt to provide automatic closing of wells to prevent well blowouts. However, even the best of the safety valves are subject to malfunctioning, particularly after they have been left in a well for a long period of time. Since the government requires periodic testing of the safety valves, those that are defective can be located, but with the previously known valves, even if they were found to be defective, nothing could be done to immobilize or replace the defective valve, short of shutting down the well and attempting a removal of the defective valve with all of the attendant problems.
SUMMARY OF THE INVENTION
The present invention relates to a ball-type safety valve which is adapted to be placed downhole in a well tubing for normally functioning to close off any flow of oil through the tubing when the fluid pressure in the well reaches a predetermined point. A lock means is provided with the valve for locking the valve in an open position so that the valve is effectively removed from use while being left in the well tubing, whereby other safety devices such as the "Storm" choke can be positioned in the well so that some safety means in still available in the well tubing.
Also, the safety valve of this invention can be temporarily locked open while performing well operations therethrough or for any other purpose, and later the locking means can be released. Both the locking and the releasing may be accomplished using fluid pressure supplied through the well tubing from the surface.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1A, 1B and 1C are views partly in elevation and partly in section, from the top to the bottom of the safety valve of this invention, with FIG. 1C being taken on line 1C--1C of FIG. 7 to better illustrate the eccentric valve pivots;
FIGS. 2A, 2B and 2C are views similar to FIGS. 1A, 1B and 1C, respectively, but showing the parts in different positions;
FIGS. 3-9, inclusive, are transverse sectional views taken on the corresponding section lines of FIG. 1C;
FIG. 10 is an exploded isometric view of the ball-valve and one-half of the valve pivot unit which is operably connected therewith;
FIGS. 11-13 are schematic views illustrating consecutive positions of the ball-valve relative to the pivot pins as the ball-valve moves from the open position, to an intermediate position, and then to the closed position;
FIG. 14 is a view similar to FIG. 10, but illustrating a modification wherein the pivot pins are carried by the ball-valve and the slots are formed in the pivot unit;
FIG. 15 is a view illustrating a typical bridge plug in position within the safety valve of this invention for directing fluid pressure to actuate the lock means of the valve for locking the valve in the open position; and
FIG. 16 is a vertical sectional view, illustrating a conventional cross-over plug mounted in the safety valve of this invention for directing fluid to the lock means for releasing same when it is desired to re-open the valve after it has been locked.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The safety valve of this invention has a housing H which includes three sections 12, 13, and 14 coupled together at threads 15 and 16, and provided with O-ring seals 15a and 16a. The upper housing section 12 terminates in an adapter 17 having a threaded box 18 for attachment in a tubing string thereabove (not shown). At the lower end of lower housing section 14, partially longitudinally cut-away female threads 19 (to be further described) are provided for threaded engagement with male threads 20 on an adapter 21 having external threads 22 at its lower extremity for attachment to a section of the tubing string therebelow (not shown). An O-ring seal 20a is provided between the adapter 21 and the housing section 14. One or more set screws 23 are provided to prevent an inadvertent release of the threaded connection 19, 20.
The wall of the top housing section 12 (FIG. 1A) has a longitudinally formed passage 25 terminating in a threaded fitting 2d for attachment of a hose or pipe 27 leading to the ground level or surface. The passage 25 connects through a port 28 with a chamber 29 between the section 12 and an upper valve actuator sleeve 30 slidably received in the housing H. Packings 31 and a packing nut 32 are provided in chamber 29, while the other end of the chamber is formed by an inclined wall 33 on an annular collar 34 formed on the sleeve 30. The collar 34 slidably engages the inner wall of housing section 12 and is provided with a sealing O-ring 35. A second chamber 38 between the sleeve 30 and the section 12 and beneath the collar 34 communicates exteriorly of the housing H through a circumferential row of ports 39 for the egress and ingress of fluid during longitudinal movement of the sleeve 30 relative to the housing H. A stop ring 40 is provided which bears against an internal shoulder 41 on the section 12. A packing 42 is positioned beween the ring 40 and the threaded end 43 of intermediate housing section 13. One or more securing set screws 45 may be provided (dotted lines, FIGS. 1B, 2B).
A third annular chamber 46 is provided between upper sleeve 30 and the intermediate housing section 13, and this chamber communicates interiorly of the sleeve 30 through ports 47 (FIG. 1B). An enlarged portion of the chamber 46 slidably receives a locking piston 48 which carries O-rings 49 and 50 and preferably has a reduced nose 51 at its lower end with an inclined or beveled extremity 52 normally bearing against a split spring ring locking detent 53. A locking sleeve 54 is slidable in the enlarged part of chamber 46 and encompasses and confines a coiled spring 55 under compression which normally urges the locking sleeve 54 against the locking detent 53 to confine same between the sleeve 54 and the piston 48. The locking sleeve 54 is abreast of and covers a locking recess 56 in the wall of housing section 13 during normal operation of the valve, as will be more fully explained. The spring 55 is compressed between a seat 57 on the sleeve 54 and a stop ring 58 bearing against a shoulder 59 formed adjacent threads 60 at an intermediate portion of the upper housing section 30. The upper valve actuating sleeve 30 has a collar 62 disposed in a fourth annular chamber 63 between the housing section 14 and a ball-type valve B (FIGS. 1C, 10). The collar 62 has an inclined valving surface 65 provided with an O-ring seal 66 for engagement with inclined sealing shoulder 67 on the housing section 14. An annular seat ring 68 formed of rubber, metal, plastic or other suitable material is internally threaded in the collar 62 for sealingly engaging the upstream face of ball valve B.
As best shown in FIG. 9, the collar 62 has four external splines or wings 71 in quadrature slidably positioned in corresponding longitudinal grooves in the inner surface of housing section 14, with sector-shaped ridges 72 therebetween which prevent rotation of the sleeve section 30 relative to the housing H.
At the lower end of housing section 14, the internal threads 19 are longitudinally cut away to form longitudinal slots 19a to provide for insertion of the valve and actuator assembly into the housing H, as will be explained. However, male teeth 20 on the adapter sub 21 are not cut away. Slidably received in a slightly enlarged upper portion 74 of the adapter sub 21 is the lower valve actuator sleeve 75 which, at its upper end, bears against the ball valve B.
The lower sleeve 75 has an intermediate external collar 76 extending into a fifth chamber 77' for engagement by a heavy coiled compression spring 77 which also engages the adapter 21, and which is encompassed by a retainer sleeve 78 having radial wings 79 in quadrature (FIGS. 4-6). The inner circular portion of sleeve 78 extends only between the end of the adapter 21 and the pivot valve unit 80, which is preferably cylindrical and longitudinally split (FIGS. 5 and 6) to facilitate assembly. The wing portions 79, however, extend upwardly into the spaces between radial wings 82 and 83 on the valve pivot means 80 (FIG. 5).
The valve pivot means 80 has upward diametrically spaced tongue portions 85 (FIGS. 7, 8 and 10) with radial wings 86 bearing against the housing H and aligned and circumferentially coextensive with wing portions 83 (FIG. 5) at the lower end of the pivot means 80. Between the wing portions 83 and 86, the pivot means 80 has annular recesses 88 to receive sector shaped ridges 89 on the housing section 14 (FIG. 6). The tongues 85 include inwardly projecting pivot pins 90 (FIGS. 1C, 7 and 10) which are received in slots or recesses 91 in the flat side surfaces 92 on ball valve B. The tongue parts 85 have complementary flat surfaces 95 abutting the valve surfaces 92 and upon which the valve surfaces rotate. The valve B is generally ball shaped (FIG. 10) with a cylindrical through passage 96 which, in diameter, substantially equals the internal diameter of the valve actuator sections 30 and 75 and also the adapters 17 and 21 which, in turn, have substantially the same internal diameter as that of the conventional tubing string (not shown) connected thereto. In other words, the valve has a full opening when in the open position (FIG. 2C) for the passage of well tools and for performing well operations therethrough.
The parts may be assembled in the following sequence:
1. The portion of the valve actuator sleeve 30 below the threads 60 is inserted in the lowermost housing section 14 from the bottom and turned as necessary to align its terminal wings 71 (FIG. 9) so as to pass between the internal sectoral ridges 72 on the housing H so that the O-ring 66 seats against the housing shoulder 67.
2. The piston 48, locking detent 53, locking sleeve 54, spring 55, and stop ring 58 are inserted upon the upper valve actuator sleeve 30 which is then screwed together at the threads 60 with its portion therebelow.
3. The housing section 13 is then screwed together with section 14 at the threads 15 so that the annular recess 56 is bridged by the locking sleeve 54.
4. The packing 42 and the stop ring 40 are applied upon protruding sleeve 30.
5. The packing 31 and the packing nut 32 are inserted in housing section 12 through the lower end thereof, and then the section 12 is attached at threads 16 to the end of the housing section 13.
6. The ball valve B is next inserted. Since the maximum diameter portions of the ball valve B are greater than the internal diameter of the crests of the threads 19 (Compare FIGS. 3 and 7), the valve B must be turned to the position shown in FIG. 8 so that its four surfaces are positioned in the longitudinal slots 19a cut in the threads 19 (Compare FIGS. 3 and 8). After the ball valve B is above the threads 19, the valve pivot unit 80 is inserted with its aligned splines or wings 83, 86 also aligned with the slots 19a. When the unit 80 is above the threads 19, the pivot pins 90 are moved into the pivot slots 91 of the ball valve B, and to accomplish this, a slight rotation of the ball valve B, about twenty degrees, towards an open position is necessary. After the pins 90 are in the slots 91, the ball valve B and unit 80 are rotated about the longitudinal axis enough to align the splines 83, 86 with longitudinal grooves 89a so that the ball valve B can then be moved to the seated position (FIG. 1C) in contact with the ring 68 at which time the ball valve B and the unit 80 are rotated about the longitudinal axis ninety degrees to position the lugs 86 directly above the lugs 89 to thereby fix the unit 80 in the housing H (FIGS. 7 and 8). Thereafter, the retainer sleeve 78 is positioned so that it can be moved upwardly with the splines 79 moving upwardly through the slots 19a to the position shown in FIG. 1C. The lower actuator sleeve 75 and the spring are then positioned as shown so that when the adapter 21 is threaded to its fully connected position, the retainer sleeve 78 and the unit 80 are locked against movement while the spring 77 is subject to being compressed from the FIG. 1C position to the FIG. 2C position. One or moe set screws 23 are used to prevent unintentional unthreading of the threads 20 from the threads 19.
In use or operation, the safety valve of this invention is inserted in a production tubing string in a well where it is desired to provide for automatic closing of the well in the event the well pressure should become excessive, indicating possible imminence of a blowout. Normally, the spring 77 urges the lower actuator sleeve 75 upwardly to maintain the valve passage 96 transversely of the flow passage within the sleeves 30 and 75 to thereby position the valve in the closed position (FIGS. 1C and 9). The full force of well pressure then is exerted against the lower face of the ball valve B urging it into sealing contact with the ring 68, the upward movement of which is limited by the engagement of the shoulder 65 and the seal 66 with the shoulder 67, so that the flow passage is effectively sealed off. In order to open the valve, control fluid under pressure is supplied selectively from the surface through the pipe 27, passage 25 and port 28 and applied to the annular wall 33 and seal 35 on the upper actuator section 30, which move the upper actuator section 30 downwardly and cause rotation of the ball valve B about the pivot pins 90 from the closed position (FIG. 13) to a partially open position (FIG. 12) and finally to the open position (FIGS. 2A and 11) with the valve passage 96 aligned with the flow passages through the valve actuator sections 30 and 75.
It should be noted that when the control fluid is supplied to open the valve B, the upper valve actuator sleeve 30 moves downwardly so as to unseat the seal ring 66 from sealing contact with the surface 67 before the ball valve B has rotated enough for its annular edge 96a (FIG. 10) to enter the bore of the sleeve 30. This results in a by-pass of fluid around the valve B prior to directing flow through the flow passage 96 thereof, whereby erosive fluid cutting action along such edge 96a is minimized, and the effective life of the ball valve B is increased, as compared to prior art constructions.
In the fully open position of the ball valve B, the spring 77 is substantially fully compressed (FIG. 2C). Thus, in normal operation of the safety valve of this invention, the ball valve B is held in the open position by the control fluid which is at least sufficient to overcome the returning force of the spring 77. It is to be noted that the cross-sectional area of the upper end of the sleeve 30 is less than the cross-sectional area of the sleeve 30 at the ports 47, so that the well fluid is also acting to maintain an upward force on the sleeve 30, which likewise must be overcome by the control fluid to move the ball B to the open position. To return the ball valve B to the closed position automatically when the well pressure reaches a predetermined point, such well pressure below the ball valve B must be sufficiently high to overcome the control fluid pressure. When the control fluid pressure has been overcome or offset by the downhole well pressure acting upwardly below the valve B, the compressed spring 77 then acts to move the lower valve actuator sleeve 75 upwardly so that the ball B is rotated about the eccentric pivot pins 90 to rotate the ball valve B from the open position (FIG. 2C) to the closed position (FIG. 1C).
During normal operation of the safety valve of this invention, the fluid pressure acting on the piston 48 is equalized since there is fluid communication above the piston 48 through the ports 47 and below the piston 48 through the ports 98. However, should it become desirable to lock the ball valve B in the fully open position illustrated in FIG. 2C, this may be accomplished by lowering a conventional bridge plug P (FIG. 15) into the tubing string T so that the plug P is disposed in the sleeve 30 between the upper ports 47 and the lower ports 98. The bridge plug P may be suspended in the tubing string T in a recess 90 formed at a joint or collar in the conventional manner, using spring-loaded catch fingers 91 or any other suitable releasable support means as is well known to those skilled in the art. Thus, after the bridge plug P has served its purpose, it may be removed from the tubing string T so that normal operations may occur through the tubing string T and the valve of this invention.
When the bridge plug P is positioned as illustrated in FIG. 15, fluid under pressure may then be forced downwardly through the ports 47 to the chamber 46 above the piston 48, thereby acting to move the piston 48 downwardly from its normal position (FIG. 1B) to the locked position (FIGS. 2B and 15). The downward movement of the piston 48 acts to move the locking sleeve 54 downwardly and also the radially expansible detent ring 53 downwardly so that the ring 53 becomes laterally aligned with the locking recess 56 and expands outwardly into such recess 56. The spring 55 exerts a constant upward force on the sleeve 54, but when the detent 53 has expanded outwardly into the recess 56, the spring 55 does not have sufficient force to unseat the locking ring 53 from the recess 56. Therefore, the detent ring 53 is locked in the recess 56 and prevents the sleeve 54 from moving upwardly. Since the sleeve 54 is in engagement with the annular ring 58 which in turn engages the shoulder 59 of the sleeve 30, the sleeve 30 is thereby locked in its lower position by the detent ring 53 being in the locking recess 56.
Once the piston 48 has moved the detent ring 53 downwardly enough to position it for movement into the recess 56, the bridge plug P may be removed from the well and the locking means or detent 53 will thereafter hold the ball valve B in the open position (FIG. 2C).
Although the locking means illustrated and described in connection with FIG. 15 is not used unless it is desired to leave the valve B in the open position for an extended period of time, and sometimes permanently, it occasionally develops that the ball valve B should be closed even after it has been locked open by the locking means of FIG. 15. Should this occur, a conventional cross-over plug P-1 (FIG. 16) may be lowered downwardly through the tubing string T and positioned as shown in FIG. 16. The cross-over plug P-1 is supported in a recess 90 by releasable latch fingers 91 in the same manner as heretofore indicated in connection with the bridge plug P, it being understood that such structure is conventional and may or may not be utilized. The plug P is solid and is provided with suitable seals externally for engagement with the inside surface of the actuator sleeve 30, but it does have a longitudinal port or passage 92 which communicates from the area above the cross-over plug P-1 to an annular recess 92a which is disposed over the openings 98 in the sleeve 30. A second passage 93 communicates with the area below the cross-over plug P-1 in the sleeve 30 and with an annular passage 93a which is aligned with the ports 47. To release the locking detent 53 from the locking recess 56, fluid under sufficient pressure is pumped downwardly through the tubing string T so that is passes through the passage 92, through the annular passage 92a and the inlet ports 98 for imparting an upward force to the piston 48 and the locking sleeve 54. Such fluid pressure initially forces the nose 51 upwardly to a point above the ring 53 and then the pressure must be sufficient, together with the force of the spring 55, to cause the locking ring 53 to radially contract and thus permit the locking detent 53 to move upwardly out of the recess 56. To facilitate such contraction, the detent ring 53 preferably has an upper tapered annular surface 53a which is in contact with a similar tapered surface 56a when the locking ring 53 is in the recess 56. Such surfaces permit an inward and upward sliding action of the ring 53, and since the ring is split and has sufficient space to contract back to its original diameter so as to fit within the bore of the housing section 13, the upward force thus causes the upward movement of the locking ring detent 53 back to the position shown in FIG. 16. After the ring detent 53 has thus been released to the unlocked position, the cross-over plug P-1 may be removed from the tubing string T with a fishing tool or any other suitable removing device, and thereafter, normal usage of the valve may take place if desired.
In FIG. 14, an alternate ball-type valve B-1 is illustrated, which has a pin 190 on each side 92 for fitting into a slot 191 on the pviot unit 180. Thus, the ball valve B-1 is essentially the same as the ball valve B, and the unit 180 is essentially the same as the unit 80, with like parts having like designations, except that the pins and slots for the pivoting action have been reversed. The movements of the ball valve B-1 are the same as heretofore described in connection with the ball valve B, and as will be well understood by those skilled in the art.
The foregoing disclosure and description of the invention are illustrative and explanatory thereof, and various changes in the size, shape, and materials as well as in the details of the illustrated construction may be made without departing from the spirit of the invention. | A pressure operated safety valve adapted to be mounted in a well tubing for normally being movable to an open position by control fluid supplied from the surface, and which valve is automatically closed when the well pressure reaches a predetermined amount, whereby blowouts of the well are automatically prevented. The valve has locking means therewith which is operable by fluid pressure supplied through the well tubing from the surface for locking the valve open in the event the valve is malfunctioning in its normal operation and a "Storm" choke or other type of safety valve is to be added in the well tubing, or it is desired to temporarily or permanently lock the valve open for any other purpose. Means are also provided for releasing the locking means to return the valve to its normal operating condition if desired. | 4 |
BACKGROUND OF THE INVENTION
The present invention relates to systems for heating the interior of a vehicle. In particular, the present invention is an improvement to heating systems in certain vehicles such as the 1974-78 Ford Pinto and Mustang II automobiles equipped with 2300 cc engines.
The 1974-78 Ford Pinto and Ford Mustang automobiles equipped with the 2300 cc engines (and the comparable Mercury automobiles) have exhibited chronic poor heating performance, particularly when operated in cold climates. During cold weather conditions, the heaters of these automobiles are slow to provide heat to the passenger compartment and often provide inadequate heat even after the car has been running for an extended period of time.
The coolant flow in these vehicles is generally as follows: The coolant is picked up at about mid-engine head and then is routed through an aluminum intake manifold. The coolant passes out of the aluminum intake manifold through an outlet and is then routed through the automatic choke and finally by metal tubing and rubber hose to the heater core. The remaining heat in the coolant is then dissipated, and the coolant is returned to the engine water pump by way of metal tubing and rubber hose. As a result of this coolant circulation arrangement, the coolant which is supplied to the heater core already has had a substantial amount of heat dissipated from it. The output of the heater is, of course, limited by the amount of heat which can be extracted from the coolant.
SUMMARY OF THE INVENTION
In the present invention, the coolant flow within the system is rerouted to increase the heat output of the heater core. The present invention includes adapter means which is connected between a first engine coolant passage outlet and the thermostatic valve. The adapter means has an auxiliary outlet which permits coolant to flow from the engine. Means such as a rubber hose connects the auxiliary outlet to the heater core inlet.
In those engines having an automatic choke mechanism which requires that coolant be routed through the choke mechanism, the present invention further includes a "T" connector having first, second and third legs. A first hose connects the heater core outlet and the first leg; a second hose connects the coolant pump inlet and the second leg; and a third hose connects the automatic choke mechanism outlet and the third leg. The third leg preferably includes a restricting orifice which restricts the flow of coolant through the choke mechanism and ensures a maximum flow of hotter coolant through the heater core.
In those engines having an electrical automatic choke, a plug is provided to plug the outlet on the intake manifold from which coolant was previously supplied to the heater core.
As a result of the present invention, coolant is derived from the location where it has its maximum heat content (i.e. immediately proximate the thermostatic valve). This coolant is routed directly to the heater core to maximize the possible output of the heater core. Significant improvement in heater performance has been obtained using the adapter of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a pictoral view showing a prior art vehicle engine and heater system.
FIG. 2 shows the pictoral view of a vehicle engine and heater system similar to that of FIG. 1, but modified in accordance with the present invention.
FIG. 3 is an exploded view showing the coolant outlet, the thermostat and the heater adapter of the present invention.
FIG. 4 shows the "T" connector used in the embodiment of the present invention shown in FIG. 2.
FIG. 5 is a pictoral view of a prior art vehicle engine and heater system, similar to that shown in FIG. 1 except that an electric rather than a water-heated automatic choke is provided.
FIG. 6 is a pictoral view of another embodiment of the present invention modifying the engine and heater system shown in FIG. 5.
FIG. 7 is a graph showing comparative test results of a 1975 Ford Pinto with 2300 cc engine, with and without the heater adapter of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 shows a prior art automobile engine 10, radiator 12, and heater 14 such as used in the Ford Pinto, Ford Mustang II, Ford Fairmont and Mercury Bobcat, with 2300 cc engine. Engine 10 has been partially broken away to illustrate the flow of coolant throughout the engine. As shown in FIG. 1, coolant from near the bottom of radiator 12 is supplied through hose 16 to waterpump 18. The coolant supplied is relatively cool comparatively, and is designated by open arrows. The coolant is circulated within the engine block.
Hot coolant (designated by the solid arrows) passes out of the engine block, through passages in aluminum intake manifold 20, to an outlet 22 located about midway from the front to the rear of the engine. The coolant is then routed from outlet 22 through flexible tubing 24 to automatic choke mechanism 26. The coolant is then routed out of outlet 28 and through metal and flexible tubing 30 to the inlet of heater 14. The heat content within the coolant is dissipated in the heater core of heater 14 and then is returned to water pump 18 through tubing 32.
The coolant within engine 10 with the highest temperature is generally found near engine block outlet 34, at which is located a thermostat (not shown in FIG. 1). The thermostat controls the flow of the hot water out of outlet 34 through connector 36 and hose 38 to radiator inlet 40 near the top of radiator 12.
It can be seen that a considerable amount of the heat in the coolant is dissipated during the flow of coolant from the engine block through manifold 20, through hose 24, automatic choke mechanism 26, and tubing 30 before it reaches the core of heater 14. This results in chronic poor heater performance in automobiles such as the Ford Pinto, Ford Mustang II, and Mercury Bobcat equipped with the 2300 cc engine.
One preferred embodiment of the present invention is illustrated in FIGS. 2-4. The present invention is a modification of the system shown in FIG. 1, and similar numerals are used to designate similar elements.
In the embodiment shown in FIG. 2, a heater adapter 42 is inserted between outlet 34 of the engine block and thermostat 44. Connector 36 and thermostat 44 are mounted to heater adapter 42, as best shown in exploded view shown in FIG. 3.
Heater adapter 42 includes flange 42a and an auxiliary outlet 42b. Coolant is permitted to flow out of outlet 34 in the block, through flange 42a, to thermostat 44. In addition, outlet 42b communicates with the central opening of flange 42a so that coolant can flow from the engine block through outlet 34 and out auxiliary outlet 42b, even when the thermostat 44 is closed.
Hose 46 connects auxiliary outlet 42b and the inlet of heater 14. As a result, the highest temperature coolant within the engine block, i.e. the coolant closest to thermostat 44, is derived from the engine block by heater adapter 42 and is supplied through auxiliary outlet 42b and hose 46 to heater 14.
As shown in FIG. 2, return hose 32 is cut in two or is replaced by two new segments, 32a and 32b. Segment 32a connects the outlet of heater 14 to first leg 48a of "T" connector 48. Section 32b connects second leg 48 of "T" connector 48 to an inlet of waterpump 18. The third leg 48c of "T" connector 48 is connected to outlet 28 of the automatic choke mechanism by metal and flexible tubing 50. In some cases, metal and flexible tubing 30 of FIG. 1 may be converted to metal and flexible tubing 50 by merely cutting off a part of the flexible tubing to make it shorter.
FIG. 4 shows a preferred embodiment of "T" connector 48, in which a restricting orifice 52 is provided in third leg 48c. This restricts the flow of coolant from outlet 22 through hose 24, through choke mechanism 26, outlet 28 and through tubing 50. The amount of coolant that is permitted to flow is just that required to provide adequate operation of the automatic choke. The orifice 52 ensures that maximum flow of hotter coolant is through hose 46 to the inlet of heater 14 and from the outlet of heater 14 through hose sections 32a and 32b and the main two legs 48a and 48b of "T" connector 48. Operation of the choke mechanism is unchanged by this rerouting of the coolant flow.
In a preferred embodiment of the present invention, flange 42a of heater adapter 42 has a 1/2" thickness. The central opening of flange 42a has an inside diameter of 15/8". Holes are provided at opposite ends of flange 42a on 25/8" centers, which match the holes used for bolting the existing connector 36 to the engine block.
The auxiliary outlet 42b is preferably a 5/8" pipe which is connected to the side of flange 42a. An opening through the side of flange 42a is provided so that the pipe 42b communicates with the central opening of flange 42a and coolant flows out of the adapter through the 5/8" pipe.
FIG. 5 illustrates another prior art arrangement, which was used on 1977 models of Ford Mustang II and Ford Pinto. On these models, an electric choke is used, so that coolant is not routed through the choke mechanism.
FIG. 5 illustrates this arrangement, with similar numbers to those used in FIG. 1 being used to designate similar elements. The only change in the routing of coolant in the embodiment shown in FIG. 5 is that the coolant is provided directly from outlet 22 on intake manifold 20 through tubing 54 to the inlet of heater 14. Otherwise, the coolant circulation is identical to that shown in FIG. 1. As in the system shown in FIG. 1, this system suffers from poor heating because a great deal of heat has been dissipated from the coolant before it reaches heater 14.
FIG. 6 illustrates the modified heater system using the heater adapter of the present invention. In the embodiment shown in FIG. 6, heater adapter 42 is once again inserted between connector 36 (and thermostat 44 not shown in FIG. 6) and outlet 34. Once again, the coolant with the highest temperature available within the engine block is routed through tubing 46 to the inlet of heater 14. This assures the greatest possible amount of heat transfer in heater 14. The other modification of the engine and heater system shown in FIG. 6 is the use of plug 56, which plugs outlet 22. Because coolant for heater 14 is now being derived from auxiliary outlet 42a, outlet 22 is no longer needed and can be plugged by plug 56. Alternatively, if desired, outlet 22 may be connected to hose 32 by means of a "T" connector in a similar manner to the connection of outlet 28 in FIG. 2.
The present invention has provided significant improvement in the operation of the heater. Table 1 and FIG. 7 illustrate the results of tests performed on a 1975 Ford Pinto with 2300 cc engine, both with the standard heater system and using the heater adapter of the present invention. To test the performance, the output air temperature at the heater duct was measured with blower control selecting the second to top blower speed and the heat control being in the maximum temperature position. These measurements were made at various outside air temperatures after 10 minutes of driving at 55 m.p.h. and after 20 minutes of driving at 55 m.p.h. The present invention yielded air temperatures from the heater duct which were significantly higher than those available with the standard heater system. After 20 minutes of driving at 55 m.p.h., the air temperature had stabilized at approximately 170° F. over a range of outside temperatures from about 17° F. to 45° F. The tests illustrate that the present invention provides quicker heat up and faster stabilization of temperature than was possible with the prior art heater system.
TABLE 1__________________________________________________________________________STANDARD INVENTIONOUTSIDE DUCT TEMP. DUCT TEMP. OUTSIDE DUCT TEMP. DUCT TEMP.TEMP. 10 MIN. 20 MIN. TEMP. 10 MIN. 20 MIN.__________________________________________________________________________+ 9° 144° 150° +17° 156° 170°+20° 150° 154° +29° 160° 170°+26° 150° 156° +32° 160° 170°+31° 150° 156° +34° 160° 170° +45° 164° 170°__________________________________________________________________________
It can be seen that the present invention is extremely simple to install and uses a minimum of additional parts. Depending upon the condition of the various hoses, the installation of the present invention may involve the use of only three new parts. For example, in the embodiment shown in FIG. 2, the new parts are adapter 42, hose 46 and "T" connector 48. The main hoses 30 and 32 previously used may be cut to accommodate the "T" connector 48. In the embodiment shown in FIG. 6, the new parts are adapter 42, hose 46 and plug 56.
In conclusion, the present invention is an effective modification of a heating system in automobiles such as the 1974-78 Ford Mustang II or Pinto, which overcomes a chronic poor heating problem, particularly in cold weather. The present invention is inexpensive and simple to install and uses a minimum of parts. It may be used as a kit for modifying existing automobiles, as well as a standard feature on new production automobiles.
Although the present invention has been described with reference to preferred embodiments, workers skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the invention. | An adapter improves the performance of the heater system in certain automobiles such as 1974-1978 Ford Pinto and Mustang II cars equipped with the 2300cc engines. An adapter is connected between the engine and the thermostat to permit coolant (i.e. water and "anti-freeze") to be routed from near the thermostat directly to the heater core inlet. This permits the coolant having the highest temperature within the engine to be provided to the heater core, thereby significantly increasing the available heat output of the heater core. | 5 |
BACKGROUND OF THE INVENTION
The invention relates to a method for correcting a pressure value detected in a fluid on the basis of a pressure of a surrounding medium, as well as to a pump system with a level sensor and to the use of a pressure sensor in a corresponding pump system.
Submersible pumps are usually equipped with a level sensor or a level switch which switches the pump on and off in dependence of the fluid level in the pump sump. With this pressure sensors may be used as level sensors which detect the fluid pressure. Since the fluid pressure changes in dependence on the height of the fluid level above the pressure sensor, by way of the fluid pressure one may determine the liquid level and accordingly switch the pump on and off. With this however it is a problem that changes of the atmospheric pressure likewise have an effect on the detection by the pressure sensor. Thus when determining the fluid level inaccuracies occur due to fluctuations in the pressure of the surroundings. In order to compensate these, in the past differential pressure sensors have been applied as pressure sensors which determine the pressure difference between a fluid pressure and the pressure of the surroundings and thus permit the exact height of the fluid level above the pressure sensor to be determined. The application of these sensors however demands a tube or a flexible tubing to be led out of the pump sump in order to also be able to impinge the pressure sensor with the pressure of the surroundings. This renders the construction and the assembly of such pumps quite complicated.
BRIEF SUMMARY OF THE INVENTION
It is therefore the object of the invention to provide an improved method for correcting a pressure value detected in a fluid on the basis of a pressure of a surrounding medium, as well as a corresponding pump system which permit a simplified construction of the pump system.
This object is achieved by a method with the features of detecting a differential pressure or for correcting a pressure value detected in a fluid on the basis of another pressure, wherein at one point in time one detects a first pressure and another point in time a second pressure, and the second pressure is corrected on the basis of the first pressure. The object may also be achieved by a pump system with a level sensor which comprises a pressure sensor for determining an absolute pressure, and a control means which switches the pump on and/or off in dependence on the readings of the level sensor, wherein the pump comprises a calibration means which controls the pump such that for calibration a fluid level is lowered below the level of the pressure sensor so that this detects the pressure of the surroundings as well as by the use of a pressure sensor with the features of a pressure sensor impinged on one side in a pump system, wherein the pressure sensor only has electrical connection conduits.
Other preferred embodiment forms are to be deduced from the accompanying dependent claims.
The method according to the invention serves for correcting a pressure value detected in a fluid on the basis of the pressure of a surrounding medium, wherein with this, there is formed a pressure difference between a first pressure value and a second pressure value, for example, of the surrounding medium. According to the invention at one point in time a first pressure value and at another point in time a second pressure value is detected. Subsequently the second pressure value is corrected on the basis of the first pressure value, wherein preferably a pressure difference between the two detected pressure values is evaluated. This method according to the invention thus allows a pressure sensor to detect absolute values only, but at two different points in time, in order to determine a pressure difference. Thus a differential pressure sensor which is impinged on two sides may be done away with. The method according to the invention permits the evaluation of a pressure difference with a sensor impinged on one side. This has the further advantage that in such a sensor which usually comprises a membrane, the detection electronics may be arranged on a side of the membrane which is not impinged by pressure. This simplifies the insulation or sealing of the electronics with respect to the fluid in which the pressure is to be determined. A simplified sensor construction is thus possible.
The method according to the invention may be applied comprehensively wherever a differential pressure is to be determined or a measured pressure value is to be preferably continuously corrected on the basis of a further pressure value. The method may for example be applied in order to determine a differential pressure in a closed system or in order to continuously correct a pressure value measured in a fluid on operation of an installation, on the basis of a pressure of a surrounding medium. At the same time for example one may firstly determine the pressure of the surrounding medium and then at a second later point in time the pressure of the fluid may be determined and the latter may be corrected then on the basis of the pressure of the surroundings by forming the differential pressure. Alternatively to this one may firstly determine the fluid pressure, and subsequently the pressure of the surroundings.
There is provided at least one pressure sensor serving as a level sensor in a submersible pump and at the one point in time the pressure of the surroundings and at the other point in time the pressure of the fluid to be delivered by the pump is detected. This embodiment of the method permits the design of a simplified level sensor for a pump. It is no longer necessary to apply a pressure sensor impinged on both sides which is simultaneously impinged by the pressure of the surroundings and by the pressure of the fluid to be delivered, and to determine the height of the fluid level via the measured differential pressure. According to the invention one may apply a pressure sensor impinged on one side, wherein the pressure of the surroundings and the pressure of the fluid to be delivered by the pump may be determined at two different points in time. This method may preferably be used where pressure changes of the surroundings occur slowly. This is the case with pumps, since the atmospheric pressure of the surroundings changes relatively slowly whilst the pressure of the fluid to be delivered may rapidly change due to the rapid changes of the fluid level. Due to the slow changes of the pressure of the surroundings a continuous detection of the pressure of the surroundings for correcting the fluid pressure is not necessary. It is sufficient to detect the pressure of the surroundings at predefined points in time and subsequently to correct the continuously determined fluid pressure by this previously detected value. The detection of the pressure of the surroundings and of the pressure of the fluid to be delivered may for example be effected by one and the same sensor. For this the sensor may be connected to the fluid and the surrounding medium or to the surroundings via tube conduits in order to determine the pressure of the fluid and of the surrounding medium or surroundings alternately or in succession. For this one may provide suitable switch valves in the tube conduits in order to impinge the pressure sensor alternately with the fluid pressure and with the pressure of the surrounding medium.
The pressure sensor, for detecting the pressure of the surroundings at the one point in time is preferably brought into a position above the surface of the fluid to be delivered. This may be effected by movement of the pressure sensor or a change of the fluid level. If the sensor is arranged above the fluid level it is located outside the fluid in the surroundings and here may determine the pressure of the surroundings.
Accordingly the pressure sensor preferably for detecting the pressure of the fluid to be delivered at the other point in time is brought into a position below the surface of the fluid to be delivered. In this position the pressure sensor is submersed into the fluid and may determine the fluid pressure.
Preferably for determining the pressure of the surroundings the fluid level is lowered below the level of the pressure sensor and the pressure sensor detects the pressure of the surroundings for correcting the pressure value detected in the fluid. The lowering of the fluid level below the level of the pressure sensor is preferably effected by the pump itself. For this the pump is activated by a control means such that at a predefined point in time at which the pressure of the surroundings is to be determined, it pumps away the fluid to the extent that the pressure sensor is pumped free and the pressure of the surrounding medium or the pressure of the surroundings may be determined outside the fluid. This method permits the application of only one pressure sensor for determining the pressure of the surrounding medium and of the fluid pressure without complicated and long connection conduits being necessary, which connect the pressure sensor to the surrounding medium and the fluid to be delivered. Indeed in contrast, for determining the pressure of the surroundings, the pressure sensor is laid free temporarily by pumping away the fluid.
After reaching the level of the pressure sensor the fluid level is preferably lowered to a predefined value below the level of the pressure sensor. In this manner it is ensured that the pressure senor is indeed located outside the fluid and may determine the pressure of the surrounding medium without any errors. Whether the level of the pressure sensor is reached or fallen short of may be ascertained in that on lowering of the fluid level the pressure detected by the pressure sensor firstly drops and then remains constant on reaching the level of the pressure sensor.
For this the fluid level after reaching the level of the pressure sensor is preferably further lowered during a period of time. Thus a pump may, for example, be controlled such that after reaching the level of the pressure sensor it still runs for a predefined time duration so that it is ensured that the pressure sensor is laid free for determining the pressure of the surrounding medium.
The period of time in which the fluid level is further lowered is preferably calculated on the basis of the lowering speed of the fluid level which has been previously detected by the level sensor. In this manner independently of the size of the pump sump one may ensure that the pressure sensor is laid free in a manner such that the pressure sensor is located above the fluid surface by a predefined amount when determining the pressure of the surrounding medium. Such a predefined distance between the pressure sensor and the fluid surface may thus be maintained without the actual fluid level after falling below of the level pressure sensor having to be determined yet again.
Preferably, the pump is switched off after reaching the level of the pressure sensor after completion of the period of time or on reaching a predefined fluid level below the level of the pressure sensor. It is thus ensured that a pump sump is not pumped completely empty also during the evaluation of the pressure of the surrounding medium, and in particular that the pump does not run dry, which could make a restart of the pump at a later point in time more difficult or even prevent this. It is ensured that the suction port of a pump is always situated below the fluid level.
It is further preferred for the detection of the pressure of the surroundings to be effected only if the fluid level remains below the level of the pressure sensor a predefined period of time. This may be ascertained in that after switching off the pump, the fluid level again rises not too quickly and with at a speed which is not too high. If the fluid level rises too quickly, then it may be the case that the draining of the fluid by pumping away corresponds to the admission into the pump sump so that indeed the fluid level does not fall at all and the sensor accordingly is not pumped free. According to a further preferred embodiment form the pump is started again if the detection of the pressure of the surroundings has not been effected. This means that if it is ascertained that if the correct condition in which the pressure of the surroundings may be determined has not been reached, the pump is started again in order to further reduce the fluid level and to bring the pressure sensor into a position above the fluid level in order to determine the pressure of the surroundings.
A method step for determining the pressure of the surroundings is preferably started if the fluid level begins to sink at a predefined minimum speed. The evaluation of the pressure of the surroundings may thus preferably be started in the manner such that firstly the pump is started in order to reduce the fluid level. If it is now ascertained by the pressure sensor that the measured pressure or the fluid level sinks at a predefined minimum speed the control means induces the previously described procedure for determining the pressure of the surroundings. Since this procedure is only started at a predefined minimum speed, it may be ensured that a drop of the pressure of the surroundings alone does not lead to the start of the procedure for determining the pressure of the surroundings.
Preferably the detection of the pressure of the surrounding medium is effected at predefined, preferably regular points in time. For example the pressure of the surroundings may be determined hourly, wherein afterwards the determined fluid pressure values may be corrected with the determined value of the pressure of the surroundings. The time intervals in which the pressure of the surroundings is determined depend on the speed at which changes of the pressure of the surroundings are to be expected. If quicker changes of the pressure of the surrounding medium are to be expected, then a more frequent determining of this pressure is required in order to guarantee a sufficiently accurate correction of the pressure value determined in the fluid. If only very slow pressure changes are to be expected in the surrounding medium the intervals between the individual pressure measurements in the surrounding medium may be selected longer.
The invention relates further to a pump system with a level sensor which comprises a pressure sensor for determining the absolute pressure. This means that a pressure sensor impinged on one side may be applied. Furthermore the pump system comprises a control means which switches the pump on and/or off in dependence on the readings of the level sensor. The pump according to the invention additionally comprises a calibration means which controls the pump such that for calibration a fluid level is reduced below the level of the pressure sensor so that this detects the pressure of a surrounding medium, e.g. the air pressure. Such a calibration procedure is effected preferably during the running operation at predefined points in time, further preferred at regular intervals in order to correct the pressure readings detected by the pressure sensor in the fluid to be delivered on the basis of the pressure of the surroundings so that on the basis of the pressure difference between the fluid pressure and the pressure of the surroundings one may determine the height of the fluid level above the pressure sensor on running operation in order to accordingly switch the pump on and/or off. The pump according to the invention thus requires no differential pressure sensor and no conduit into the surroundings in order to continuously determine a pressure difference between the surroundings and the fluid. Since the determining of fluid pressure and pressure of the surroundings is not effected at the same point in time, but staggered in time, it is possible to apply one and the same pressure sensor for determining the pressure of the surroundings and of the pressure of the fluid to be delivered. For determining the pressure of the surroundings only the pressure sensor which in normal operation is located in the fluid is pumped free as described above.
Preferably the level switch, the control means and the calibration means are an integral part of a pump unit. In this manner one creates a pump unit which is simple to install and assemble since all control and measurement means are integrated into the pump unit. All means are preferably integrated into the pump housing so that the pump unit only needs to be inserted or suspended into a pump sump.
The pressure sensor is preferably arranged above the suction port of the pump. In this manner the pump is prevented from running dry whilst pumping free the pressure sensor, which would render more difficult or even prevent the starting of the pump again. It may be ensured that the suction port is constantly situated in the fluid also during the evaluation of the pressure of the surroundings, when the fluid level is lowered below the level of the pressure sensor.
The pressure sensor is preferably attached on the stator housing or pump housing. This simplifies the assembly since the pressure sensor does not need to be fastened separately from the pump at a predefined position in the pump sump. The sensor is always located at a predefined position relative to the suction port of the pump. If the pressure sensor is rigidly connected to the stator housing or pump housing or is attached to these, then for the application of the pump it is merely necessary to insert this into the pump sump.
It is further preferred for a control means comprising the calibration means to be arranged in a terminal box or in the pump housing or stator housing. In this manner one creates a compact pump or a compact pump unit into which all control means are integrated so that the connection and starting operation of the pump are simplified.
The pressure sensor is preferably an absolute pressure sensor impinged on one side. This permits a simple and inexpensive design of the pressure sensor. For example a membrane in the pressure sensor may be impinged from one side with pressure, whilst the required electronics for determining the deflection of the membrane may be arranged on the opposite side of the membrane protected from the fluid.
The invention further relates to the use of a pressure sensor impinged on one side in a pump system according to the preceding description, wherein the pressure sensor only has electrical connection leads at its disposal. With known differential pressure sensors it is necessary to lead a flexible tubing conduit to the surface above the fluid level in order to impinge the differential pressure sensor from one side with the pressure of the surroundings. According to the method according to the invention and the pump system according to the invention this is no longer required, but one may rather use a pressure sensor impinged on one side in the pump system according to the invention.
These and other objects and advantages of the invention will be apparent from the following description, the accompanying drawings and the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
Hereinafter the invention is described by way of example by way of the attached figures. In these there are shown in
FIG. 1 a diagram which shows the course of a correction procedure, and
FIG. 2 a diagram which shows the course with which no correction is carried out.
DETAILED DESCRIPTION OF THE INVENTION
The method according to the invention and in particular the pump system according to the invention may be applied wherever a differential pressure between a fluid and a surrounding medium needs to be determined for measurement or control purposes. The method is preferably applied to a pump with which the fluid level is detected via a pressure sensor in order to switch the pump on and/or off. In order to be able to determine the exact fluid level it is necessary to determine the differential pressure between a pressure at a certain height in the fluid and the pressure of the surroundings, since otherwise fluctuations of the pressure of the surroundings would influence the determined value for the fluid or liquid level. According to the method according to the invention, for this, the pressure of the surroundings and the pressure in the fluid are not determined simultaneously but at different points in time in succession.
With a submersible pump as for example is applied for reducing the groundwater or in waste water wells, for this, at predefined points in time the fluid level is lowered by the pump to the extent that the pressure sensor serving as a level sensor is pumped free, i.e. is located above the fluid level. In this condition the pressure sensor determines the pressure of the surroundings, i.e. the air pressure. Subsequently the pump sump runs full again and the pressure sensor lies again below the fluid level so that it detects the hydrostatic pressure which is caused by the fluid lying above it. Since the pressure of the surroundings has been previously determined, the differential pressure between the pressure detected in the fluid and the pressure of the surroundings may be determined so that the hydrostatic pressure caused by the fluid alone is detected and thus one may determine the height of the fluid level in order to determine the time of switching the pump on and/or off.
An absolute pressure sensor is applied as a pressure sensor which is impinged on one side.
By way of FIG. 1 the course of a correction procedure, i.e. the course of determining the pressure of the surroundings is described in more detail. In FIG. 1 the height h of the fluid level in the pump sump or the pressure detected by the pressure sensor is plotted over the time t. The unbroken line 2 shows the course of the signal emitted by the pressure sensor over time. Firstly the pumping-away procedure is started so that the fluid level 2 or the pressure signal 2 representing the fluid level falls, until the fluid level has reached the value S 2 . The value S 2 corresponds to the height S 2 at which the pressure sensor is attached on the pump. During this pumping procedure the control means of the pump detects an average lowering speed which is represented in the diagram according to FIG. 1 as a dotted line 4 . If the fluid level has reached the level S 2 of the pressure sensor and subsequently falls short of this, the pressure sensor detects the pressure of the surroundings so that the pressure detected by the pressure sensor does not drop any further. Since the control means determines the fluid level in the pump sump via the detected pressure, at this point in time due to the constant pressure the fluid level appears to be constant to the control means, which is represented by the horizontal course of the graph 2 in FIG. 1 at the height S 2 during the time intervals t 1 and t 2 .
During the preceding pumping-away procedure, the average sinking speed of the fluid level dh/dt shown by the dotted line 4 is determined. In order to be able to ensure a perfect evaluation of the pressure of the surroundings, the fluid level should be lowered below the level S 2 to the level S 1 . In order to reach the level S 1 thus the fluid level proceeding from the level S 2 must still be lowered by the height h 1 . On account of the previously evaluated sinking speed dh/dt one may now determine the period of time t 1 in which the pump must run further with a constant power so that with a constant sinking speed the fluid level is lowered to the level S 1 by the measure h 1 . The following applies:
t 1 =h 1 /( dh/dt )
After completion of the period of time t 1 the pump is switched off and the fluid level in the interval t 2 increases again until it has again reached the level S 2 . On exceeding the level S 2 the control of the pump again detects a pressure change, and the detected signal for the fluid level which is represented by the unbroken line 2 in FIG. 1 again rises after completion of the interval t 2 .
In the interval t 2 the measurement of the pressure of the surrounding is carried out provided that the interval t 2 is longer than a predefined interval t 2 min. If the sensor signal remains constant at the value S 2 for a shorter time period than t 2min , then it is the case of the fluid admission into the pump sump compensating the fluid discharge due to the pumping-away procedure by the pump, so that the fluid level remains constant. In this condition the fluid sensor is not pumped free although it does not detect any further change of the pressure. Thus at this point in time one may not carry out a measurement of the pressure of the surroundings. If however the sensor signal remains constant at the value S 2 in a period of time t 2 >t 2min , it may be assumed that the fluid level has been lowered to below the level S 2 of the sensor and the sensor at this point in time is thus free, i.e. lies outside the fluid or the liquid and may detect the pressure of the surroundings.
Subsequent to determining the pressure of the surroundings the pump sump runs full again, and subsequently detected pressure values may be corrected on the basis of the pressure of the surroundings. The detection of the pressure of the surroundings is effected at predefined points in time, for example on an hourly basis. Since changes of the pressure of the surroundings are effected considerably slower or sluggishly than changes in the fluid level, individual measurements of the pressure of the surroundings at predefined time intervals are sufficient in order to correct the pressure detected in the liquid or fluid in order to be able to determine the exact height of the fluid level. The fluid level is proportional to the differential pressure between the fluid pressure and the pressure of the surroundings.
FIG. 2 shows a diagram which corresponds to FIG. 1 and which illustrates a further condition in which no measurement of the pressure of the surroundings has been carried out. As described by way of FIG. 1 , firstly the fluid level is lowered by starting the pump, which is detected by the pressure sensor which emits a signal level 2 . At the point in time T 1 the signal 2 in the vicinity of the level S 2 of the sensor remains constant. This causes the control means firstly to assume that the level S 2 is reached or fallen short of, so that the sensor is pumped free. As a result it now evaluates, as explained by way of FIG. 1 , the interval t 1 in which the pump must continue to run in order to lower the fluid level by the predefined amount h 1 . The pump is switched off after completion of the period of time t 1 . In the case shown in FIG. 2 now after completion of the interval t 1 the signal directly increases again. The signal level 2 thus does not remain constant for a period of time t 2 >t 2min . From the direct increase again of the signal level one may now conclude that indeed the liquid level has not been lowered below the level S 2 but that merely an admission into the pump sump has corresponded exactly to the quantity of fluid or liquid pumped away by the pump so that the signal level 2 was constant in the interval t 1 . Due to the increase again of the signal level 2 before completion of the period of time t 2min the control means now recognizes an error and does not carry out an evaluation of the pressure of the surroundings, but again starts the pump in order to start the described procedure from the beginning and to determine the pressure of the surroundings.
By way of the previously described method, without additional sensors one may exactly determine that condition in which the pressure sensor is pumped adequately free in order to determine the pressure of the surroundings. Alternatively for example a second sensor in the form of a pressure sensor or another level or moisture sensor may be provided which detects whether the pressure sensor used for the pressure measurement is located above or below the fluid level. This is important in order to be able to determine the pressure of the surroundings and the pressure in the fluid at different points in time with one and the same sensor, and to be able to correct the pressure measured in the fluid on the basis of the pressure of the surroundings or to be able to determine the differential pressure. Alternatively for example in the region of the upper end of a submersible pump one may arrange a pressure sensor for determining the pressure of the surroundings after a lowering of the fluid level, and in the region of the lower end of the submersible pump there may be arranged a further pressure sensor for determining the fluid pressure. With this arrangement too the pressure measurement of the pressure of the surroundings and of the fluid pressure at two different points in time means that it is not necessary to keep the pressure sensor constantly above the fluid level for determining the pressure of the surroundings, which would require additional connection conduits.
While the system and method described, constitute preferred embodiments of this invention, it is to be understood that the invention is not limited to this precise system and method, and that changes may be made in either without departing from the scope of the inventions, which is defined in the appended claims. | The invention relates to a method for detecting a differential pressure or for correcting a pressure value detected in the fluid on the basis of a pressure of a surrounding medium, wherein at a first point in time the pressure of the surrounding medium is detected and at a later, second point in time the pressure of the fluid is detected, and the pressure value detected in the fluid is corrected on the basis of the pressure of the surrounding medium. The invention furthermore relates to a pump system with a level sensor in which this method is applied, as well as to the use of a pressure sensor in such a pump system. | 5 |
This invention was supported by the National Institutes of Health Grant No. DK 47757-02 and AI 39412-02. The United States government has certain rights in this invention.
FIELD OF THE INVENTION
The present invention relates generally to gene therapy, and more specifically, to methods of administering viral vectors used in gene therapy.
BACKGROUND OF THE INVENTION
Recombinant adenoviruses have emerged as attractive vehicles for in vivo gene transfer to a wide variety of cell types. The first generation vectors, which are rendered replication defective by deletion of sequences spanning E1, are capable of highly efficient in vivo gene transfer into nondividing target cells M. Kay et al, Proc. Natl. Acad. Sci. USA, 91:2353 (1994); S. Ishibashi et al, J. Clin. Invest., 92:883 (1993); B. Quinn et al, Proc. Natl. Acad. Sci. USA, 89:2581 (1992); M. Rosenfeld et al, Cell, 68:143 (1992); and R. Simon et al, Hum. Gene Thera., 4:771 (1993)!.
Immune responses of the recipient to the viral vector, the transgene carried by the vector, and the virus infected cells have emerged as recurring problems in the initial application of this technology to animals and humans. In virtually all models, expression of the transgene is transient and associated with the development of pathology at the site of gene transfer M. Kay et al, cited above; S. Ishibashi et al, cited above; B. Quinn et al, cited above; M. Rosenfeld et al, cited above; and R. Simon et al, cited above!. The transient nature of the effect of recombinant adenoviruses in most situations is the development of cellular immune responses to the virus-infected cells and their elimination. Antigenic targets for immune mediated clearance are viral proteins expressed from the recombinant viral genome and/or the product of the transgene. Studies in a variety of models suggest that first generation vectors express viral proteins in addition to the transgene which collectively activate cytotoxic T lymphocytes (CTL) leading to the destruction of the virus infected cells Y. Dai et al, Proc. Natl. Acad. Sci. USA, (in press); Y. Yang et al, Proc. Natl. Acad. Sci. USA, 91:4407 (1994); and Y. Yang et al, Immunity, 1:433 (1994)!. This problem is potentially overcome through the development of second generation recombinant viruses Y. Yang et al, Nat. Genet., 7:363 (1994); and J. Engelhardt et al, Hum. Gene Thera., 5:1217 (1994)!.
The other limitation of recombinant adenoviruses for gene therapy has been the difficulty in obtaining detectable gene transfer upon a second administration of virus. This limitation is particularly problematic in the treatment of chronic diseases, such as cystic fibrosis, that will require repeated therapies to obtain life-long genetic reconstitution. Diminished gene transfer following a second therapy has been demonstrated in a wide variety of animal models following intravenous or intratracheal delivery of virus T. Smith et al, Gene Thera., 5:397 (1993); S. Yei et al, Gene Thera., 1:192 (1994); K. Kozarsky et al, J. Biol. Chem., 269:13695 (1994)!. In each case, resistance to repeat gene therapy was associated with the development of neutralizing anti-adenovirus antibody.
There remains a need in the art for a method of improving the efficiency of gene transfer during repeated administrations of viral gene therapy.
SUMMARY OF THE INVENTION
The present invention provides a method of performing gene therapy which results in a reduced immune response to the viral vector used to accomplish the therapy. The method involves co-administering with a gene therapy viral vector a selected immune modulator, which can substantially reduce the occurrence of a neutralizing antibody response directed against the vector itself and/or cytolytic T cell elimination of the vector, particularly where readministration of the recombinant virus is desired. According to this method the immune modulator may be administered prior to, or concurrently with, the viral vector bearing the transgene to be delivered.
Other aspects and advantages of the present invention are described further in the following detailed description of the preferred embodiments thereof.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1A is an alkaline phosphatase histochemical stain of lung tissue of C57BL-6 mice adenovirus-infected on day 0 as described in Example 2 (magnification×100) depicting the staining of lung tissue from normal mice ("control") necropsied on day 3.
FIG. 1B is a stain from control mice immunized as in FIG. 1A, and necropsied on day 28.
FIG. 1C is a stain from control mice, immunized as in FIG. 1A, and necropsied on day 31 following reinfection with lacZ-containing adenovirus vector on day 28.
FIG. 1D is a stain on day 3 of lung tissue from mice immunized as in FIG. 1A, and depleted on days -3, 0, and +3 of CD4 + cells with mAb ("CD4 mAb").
FIG. 1E is a stain on day 28 of CD4 mAb mice immunized as in FIG. 1A.
FIG. 1F is a stain on day 31 of CD4 mAb mice immunized as in FIG. 1A.
FIG. 1G is a stain of lung tissue from mice immunized as in FIG. 1A, and treated with IL-12 on days 0 and +1 ("IL-12") and necropsied on day 3.
FIG. 1H is a stain on day 28 of IL-12 mice immunized as in FIG. 1A.
FIG. 1I is a stain on day 31 of IL-12 mice immunized as in FIG. 1A.
FIG. 1J is a stain of lung tissue from mice immunized as in FIG. 1A and treated with IFN-γ on days 0 and +1 ("IFN-γ") and necropsied on day 3.
FIG. 1K is a stain on day 28 of IFN-γ mice immunized as in FIG. 1A.
FIG. 1L is a stain on day 31 of IFN-γ mice, immunized as in FIG. 1A.
FIG. 2A is a graph summarizing neutralizing antibody titer present in BAL samples of C57BL-6 mice adenovirus-infected on day 0 and necropsied on day 28 as described in Example 2. Control represents normal mice ("control"); CD4 mAB represents CD4+ depleted mice; IL-12 represents IL-12 treated mice and IFN-γ represent IFN-γ treated mice as described for FIGS. 1A through 1L.
FIG. 2B is a graph summarizing the relative amounts (OD 405 ) of IgG present in BAL samples. The symbols are as described in FIG. 2A.
FIG. 2C is a graph summarizing the relative amounts (OD 405 ) of IgA present in BAL samples. The symbols are as described in FIG. 2A.
DETAILED DESCRIPTION OF THE INVENTION
The present invention provides a method for improving an individual's ability to tolerate repeated administrations of gene therapy viral vectors. This method involves administering to an individual a suitable amount of a preferably short-acting, immune modulator, either concurrently with, or before or after administration of a recombinant gene therapy viral vector used to deliver a therapeutic transgene desired for gene therapy.
I. Immune Modulators
The selected immune modulator is defined herein as an agent capable of inhibiting the formation of neutralizing antibodies directed against the recombinant viral vector or capable of inhibiting cytolytic T lymphocyte (CTL) elimination of the vector. The immune modulator may interfere with the interactions between the T helper subsets (T H1 or T H2 ) and B cells to inhibit neutralizing antibody formation. Alternatively, the immune modulator may inhibit the interaction between T H1 cells and CTLs to reduce the occurrence of CTL elimination of the vector.
Immune modulators for use in inhibiting neutralizing antibody formation according to this invention are selected based on the determination of the immunoglobulin subtype of any neutralizing antibody produced in response to the adenovirus vector. The neutralizing antibody which develops in response to administration of a gene therapy viral vector is frequently based on the identity of the virus, the identity of the transgene, what vehicle is being used to deliver the vector and/or the location of delivery.
For example, the subset of T helper cells designated T H 2 is generally responsible for interfering with the efficient transfer of genes administered during gene therapy. This is particularly true when the viral vector is adenovirus-based. More particularly, the inventors have determined that neutralizing antibodies of the subtypes, IgG1 and IgA, which are dependent upon the interaction between T H 2 cells and B cells, appear to be the primary cause of major neutralizing antibodies against adenoviral vectors. Administration of adenoviral vectors via the lungs generally induces production of IgA neutralizing antibody. Administration of adenoviral vectors via the blood generally induces IgG 1 neutralizing antibody. Thus, when an adenovirus-based viral vector is used in gene therapy, this T H2 -dependent immune response interferes with transfer of the therapeutic transgene.
The identity of the neutralizing antibody for any specific gene therapy recombinant viral vector is readily determined in trials of each individual vector in animal models.
Thus, where the neutralizing antibody is a T H2 mediated antibody, such as IgA or IgG 1 , the immune modulator selected for use in this method suppresses or prevents the interaction of T H2 with B cells. Alternatively, if the neutralizing antibody is a T H1 , mediated antibody, such as IgG 2A , the immune modulator desirably suppresses or prevents the interaction of T H1 with B cells.
Where, the reduction of CTL elimination of the viral vectors is desired, the immune modulator is selected for its ability to suppress or block CD4+T H1 cells to permit prolonged residence of the viral vector in vivo.
A desirable immune modulator for use in this method which selectively inhibits the CD4+T cell subset T H2 function at the time of primary administration of the viral vector includes interleukin-12, which enhances antigen specific activity of T H1 , cells at the expense of the T H2 cell function see, e.g., European Patent Application No. 441,900; P. Scott, science, 260:496 (1993); R. Manetti et al, J. Exp. Med., 177:1199 (1993); A. D'Andrea et al, J. Exp. Med., 176:1387 (1992)!. IL-12 for use in this method is preferably in protein form. Human IL-12 may be recombinantly produced using known techniques or may be obtained commercially. Alternatively, it may be engineered into a viral vector and expressed in a target cell in vivo or ex vivo.
Another selected immune modulator which performs the same function is gamma interferon S. C. Morris et al, J. Immunol., 1:1047 (1994); F. P. Heinzel et al, J. Exy. Med., 177:1505 (1993)!. IFN-γ partially inhibits IL-4 stimulated activation of T H2 . γIFN may also be obtained from a variety of commercial sources. Alternatively, it may be engineered into a viral vector and expressed in a target cell in vivo or ex vivo by resorting to known genetic engineering techniques.
Preferably, such cytokine immune modulators are in the form of human recombinant proteins. These proteins may be produced by methods extant in the art. It is also anticipated that active peptides, fragments, subunits or analogs of IL-12 or gamma interferon which share the T H2 inhibitory function of these proteins, will also be useful in this method when the neutralizing antibodies are T H2 mediated.
A desirable immune modulator for use in this method which selectively inhibits the CD4+ T cell subset T H1 function at the time of primary administration of the viral vector includes interleukin-4, which enhances antigen specific activity of T H2 cells at the expense of the T H1 cell function see, e.g., Yokota et al, Proc. Natl. Acad. Sci., USA, 83:5894-5898 (1986); U.S. Pat. No. 5,017,691!.
Still other immune modulators which inhibit the T H cell function may also be employed in this method. Among such modulators are agents that specifically inhibit or deplete CD4+ cells, for example, by antibody to the CD4 protein. Among such agents include anti-T cell antibodies, such as anti-OKT 3+ see, e.g., U.S. Pat. No. 4,658,019; European Patent Application No. 501,233, published Sep. 2, 1992, among others!. See, Example 2 below, which employs the commercially available antibody GK1.5 (ATCC Accession No. TIB207) to deplete CD4+ cells. Depletion of CD4+cells is shown to inhibit the CTL elimination of the viral vector.
Alternatively, any agent that interferes with the activation of B cells by T H cells is useful in the methods of this invention. For example, it is necessary for the activation of B cells by T cells for certain interactions to occur F. H. Durie et al, Immunol. Today, 15(9):406-410 (1994)!, such as the binding of CD40 ligand on the T helper cell to the CD40 antigen on the B cell, and the binding of the CD28 and/or CTLA4 ligands on the T cell to the B7 antigen on the B cell. Without both interactions, the B cell cannot be activated to induce production of the neutralizing antibody.
Thus, the method of this invention may be accomplished by use of agents which can block the interactions necessary for B cell activation by T helper cells, and thus neutralizing antibody formation. An agent which blocks the CD40 ligand on the T H cell interferes with the normal binding of CD40 ligand on the T helper cell with the CD40 antigen on the B cell. Thus, a soluble CD40 molecule or an antibody to CD40 ligand available from Bristol-Myers Squibb Co; see, e.g., European patent application 555,880, published Aug. 18, 1993! can be a selected immune modulator in this method.
Alternatively, an agent which blocks the CD28 and/or CTLA4 ligands present on T helper cells interferes with the normal binding of those ligands with the antigen B7 on the B cell. Thus, a soluble form of B7 or an antibody to CD28 or CTLA4, e.g., CTLA4-Ig available from Bristol-Myers Squibb Co; see, e.g., European patent application 606,217, published Jul. 20, 1994! can be the selected immune modulator in this method.
Although less desirable than the above-listed immune modulators, other immune modulators or agents that nonspecificly inhibit immune function, i.e., cyclosporin A or cyclophosphamide, may also be useful in this method.
A suitable amount or dosage of the immune modulator will depend primarily on the amount of the recombinant vector bearing the transgene which is initially administered to the patient and the type of immune modulator selected. Other secondary factors such as the condition being treated, the age, weight, general health, and immune status of the patient, may also be considered by a physician in determining the dosage of immune modulator to be delivered to the patient. Generally, for example, a therapeutically effective human dosage of a cytokine immune modulator, e.g., IL-12 or γ-IFN, is generally in the range of from about 0.5 μg to about 5 mg per about 1×10 7 pfu/ml virus vector. Various dosages may be determined by one of skill in the art to balance the therapeutic benefit against any side effects.
II. Viral Vectors
Suitable viral vectors useful in gene therapy are well known, including retroviruses, vaccinia viruses, poxviruses, adenoviruses and adeno-associated viruses, among others. The method of this invention is anticipated to be useful with any virus which forms the basis of a gene therapy vector. However, exemplary viral vectors for use in the method of the invention are adenovirus vectors see, e.g., M. S. Horwitz et al, "Adenoviridae and Their Replication", Virology, second edition, pp. 1712, ed. B. N. Fields et al, Raven Press Ltd., New York (1990); N. Rosenfeld et al, Cell, 68:143-155 (1992); J. F. Engelhardt et al, Human Genet. Ther., 4:759-769 (1993); Y. Yang et al, Nature Genet., 7:362-269 (1994); J. Wilson, Nature, 365:691-692 (October 1993); B. J. Carter, in "Handbook of Parvoviruses", ed. P. Tijsser, CRC Press, pp. 155-168 (1990).
Particularly desirable are human type C adenoviruses, including serotypes Ad2 and Ad5, which have been rendered replication defective for gene therapy by deleting the early gene locus that encodes E1a and E1b. There has been much published on the use of E1 deleted adenoviruses in gene therapy. See, K. F. Kozarsky and J. M. Wilson, Curr. Opin. Genet. Dev., 3:499-503 (1993). The DNA sequences of a number of adenovirus types, including type Ad5, are available from Genbank. The adenovirus sequences may be obtained from any known adenovirus type, including the presently identified 41 human types Horwitz et al, Virology, 2d ed., B. N. Fields, Raven Press, Ltd., New York (1990)!. A variety of adenovirus strains are available from the American Type Culture Collection, Rockville, Md., or available by request from a variety of commercial and institutional sources. In the following embodiment an adenovirus, type 5 (Ad5) is used for convenience.
The selection of the virus for the recombinant vectors useful in this method, including the viral type, e.g., adenovirus, and strain are not anticipated to limit the following invention.
Similarly, selection of the transgene contained within the viral vector is not a limitation of this invention. This method is anticipated to be useful with any transgene. Suitable transgenes for delivery to a patient in a viral vector for gene therapy are known to those of skill in the art. These therapeutic nucleic acid sequences typically encode products for administration and expression in a patient in vivo or ex vivo to replace or correct an inherited or non-inherited genetic defect or treat an epigenetic disorder or disease. Such therapeutic genes which are desirable for the performance of gene therapy include, without limitation, a very low density lipoprotein gene (VLDL) for the treatment of familial hypercholesterolemia or familial combined hyperlipidemia, the cystic fibrosis transmembrane regulator gene (CFTR) for treatment of cystic fibrosis, DMD Becker allele for treatment of Duchenne muscular dystrophy, and a number of genes which may be readily selected by one of skill in the art. Thus, the selection of the transgene is not considered to be a limitation of this invention, as such selection is within the knowledge of the art-skilled.
The viral vector bearing a therapeutic gene may be administered to a patient, preferably suspended in a biologically compatible solution or pharmaceutically acceptable delivery vehicle. A suitable vehicle includes sterile saline. Other aqueous and non-aqueous isotonic sterile injection solutions and aqueous and non-aqueous sterile suspensions known to be pharmaceutically acceptable carriers and well known to those of skill in the art may be employed for this purpose.
The viral vector is administered in sufficient amounts to transfect the desired cells and provide sufficient levels of transduction and expression of the selected transgene to provide a therapeutic benefit without undue adverse or with medically acceptable physiological effects which can be determined by those skilled in the medical arts. Conventional and pharmaceutically acceptable routes of administration include direct delivery to the target organ, tissue or site, intranasal, intravenous, intramuscular, subcutaneous, intradermal, oral and other parental routes of administration. Routes of administration may be combined, if desired.
Dosages of the viral vector will depend primarily on factors such as the condition being treated, the selected gene, the age, weight and health of the patient, and may thus vary among patients. For example, a therapeutically effective human dosage of the viral vectors is generally in the range of from about 20 to about 50 ml of saline solution containing concentrations of from about 1×10 7 to 1×10 10 pfu/ml viruses. A preferred adult human dosage is about 20 ml saline solution at the above concentrations. The dosage will be adjusted to balance the therapeutic benefit against any side effects. The levels of expression of the selected gene can be monitored to determine the selection, adjustment or frequency of dosage administration.
III. The Method of the Invention
The method of this invention involves the co-administration of the selected immune modulator with the selected recombinant viral vector. The co-administration occurs so that the immune modulator and vector are administered within a close time proximity to each other. It is presently preferred to administer the modulator concurrently with or no longer than one day prior to the administration of the vector. The immune modulator may be administered separately from the recombinant vector, or, if desired, it may be administered in admixture with the recombinant vector.
For example, where a cytokine, e.g., IL-12 and/or γIFN, is the immune modulator, the modulators are desirably administered in close time proximity to the administration of the viral vector used for gene therapy. Particularly, the inventors have found that administration of IL-12 or γIFN causes reduction in T H 2 cell levels for about 2-3 days. Therefore, IL-12 and/or γIFN are desirably administered within a day of the administration of the viral vector bearing the gene to be delivered. Preferably, however, the IL-12 and/or γIFN are administered essentially simultaneously with the viral vector.
The immune modulator may be administered in a pharmaceutically acceptable carrier or diluent, such as saline. For example, when formulated separately from the viral vector, the immune modulator, such as IL-12 and/or γ-IFN, is desirably suspended in saline solution. Such a solution may contain conventional components, e.g. pH adjusters, preservatives and the like. Such components are known and may be readily selected by one of skill in the art.
Alternatively, the immune modulator may be itself administered as DNA, either separately from the vector or admixed with the recombinant vector bearing the transgene. Methods exist in the art for the pharmaceutical preparation of the modulator as protein or as DNA See, e.g., J. Cohen, Science, 259:1691-1692 (1993) regarding DNA vaccines!. Desirably the immune modulator is administered by the same route as the recombinant vector.
The immune modulator, e.g., IL-12 or γIFN, may be formulated directly into the composition containing the viral vector administered to the patient. Alternatively, the immune modulator, may be administered separately, preferably shortly before or after administration of the viral vector. In another alternative, a composition containing one immune modulator, such as IL-12, may be administered separately from a composition containing a second immune modulator, such as γIFN, and so on depending on the number of immune modulators administered. These administrations may independently be before, simultaneously with, or after administration of the viral vector.
The administration of the selected immune modulator may be repeated during the treatment with the recombinant adenovirus vector carrying the transgene, during the period of time that the transgene is expressed, as monitored by assays suitable to the transgene or its intended effect) or with every booster of the recombinant vector. Alternatively, each reinjection of the same viral vector may employ a different immune modulator.
One advantage of the method of this invention is that it represents a transient manipulation, necessary only at the time of administration of the gene therapy vector, and it is anticipated to be safer than strategies based on induction of tolerance which may permanently impair the ability of the recipient to respond to adenovirus infections. Furthermore, the use of immune modulators such as the above-mentioned cytokines or antibodies in preference to agents such as cyclosporin or cyclophosphamide is anticipated to be safer than generalized immune suppression because the transient immune modulation is selective (i.e., CTL mediated responses are retained as are humoral responses dependent on T H 1 function).
In one example of efficient gene transfer according to the method of this invention, the selected immune modulators are IL-12, which causes the selective induction of T H 1 cells, and/or γIFN, which suppresses induction of T H 2 cells. Another immune modulator is the anti-CD4+ antibody, GK1.5, which depletes the T H1 cells, and reduces CTL elimination of the vector. In conjunction with gene therapy which utilized an adenovirus vector containing either an alkaline phosphatase ("Alk") transgene or a beta-galactosidase ("lacZ") transgene, the use of these immune modulators permitted efficient gene transfer, as well as repeated use of the same viral vector.
As detailed in Example 2 below, animals were injected with IL-12 at the time of the first administration of a recombinant adenovirus vector. Analysis of lymphocytes stimulated in vitro with virus revealed an increased secretion of IL-2 and IFN-γ and a relative decreased production of IL-4 as compared to animals that did not receive IL-12 (i.e., ratio of IL2/IL-4 was increased from 3 to 6 when IL-12 was used). More importantly, IL-12 selectively blocked secretion of antigen specific IgA without significantly impacting on formation of IgG; this was concurrent with a 100-fold reduction in neutralizing antibody. High level gene transfer to airway epithelial cells was achieved when the adenovirus vector was readministered to IL-12 treated animals.
Similar experiments were also performed with IFN-γ which is believed to mediate many of the biological effects of IL-12 via secretion of activated macrophages and T helper cells. Mice were injected with IFN-γ using the IL-12 dosing regimen. These animals were virtually indistinguishable from the animals treated with IL-12 in that virus specific IgA and neutralizing antibody was decreased 100-fold as compared to animals not treated with cytokine and efficient gene transfer was accomplished upon a second administration of virus.
In the same experiments, depletion of the CD4+ cells were shown to effectively permit readministration of the vector without immediate CTL elimination.
The following examples illustrate the preferred methods for preparing suitable viral vectors useful in the gene therapy methods of the invention. These examples are illustrative only and do not limit the scope of the invention.
EXAMPLE 1
Construction and Purification of Exemplary Recombinant Adenovirus Vectors
The recombinant adenovirus, H5.010CMVLacZ, was constructed as follows. The plasmid pAd.CMVlacZ described in Kozarsky et al, J. Biol. Chem., 269(18):13695-13702 (1994)!, which contains adenovirus map units 0-1, followed by a cytomegalovirus enhancer/promoter Boshart et al, Cell, 41:521-530 (1985)!, an E. coli beta-galactosidase gene (lacZ), a polyadenylation signal (pA), adenovirus 5 map units 9-16 (Ad 9-16) and generic plasmid sequences including an origin of replication and ampicillin resistance gene was used. pAd.CMVlacZ was linearized with NheI and co-transfected into 293 cells ATCC CRL1573! with sub360 DNA (derived from adenovirus type 5) which had been digested with XbaI and ClaI as previously described K. F. Kozarsky, Somatic Cell Mol. Genet., 19:449-458 (1993) and Kozarsky (1994), cited above!. The resulting recombinant virus H5.010CMVLacZ contains adenovirus map units 0-1, followed by a CMV enhancer/promoter, a lacZ gene, a polyadenylation signal (pA), adenovirus map units 9-100, with a small deletion in the E3 gene.
The recombinant adenovirus, H5.010CBALP, contains the adenovirus map units 0-1, followed by a CMV enhanced, chicken cytoplasmic β-actin promoter T. A. Kost et al, Nucl. Acids Res., 11(23):8287 (1983)!, a human placental alkaline phosphatase gene, a polyadenylation signal (pA), and adenovirus type 5 map units 9-100, with a small deletion in the E3 gene (the Ad 5 sub360 backbone). This recombinant adenovirus was constructed substantially similarly to the H5.010CMVLacZ described above. See, also, Kozarsky (1994), cited above.
These recombinant adenoviruses, H5.010CMVLacZ and H5.010CBALP, were isolated following transfection Graham, Virol., 52:456-467 (1974)!, and were subjected to two rounds of plaque purification. Lysates were purified by cesium chloride density centrifugation as previously described Englehardt et al, Proc. Natl. Acad. Sci. USA, 88:11192-11196 (1991)!. Cesium chloride was removed by passing the virus over a BioRad DG10 column using phosphate-buffered saline.
For mouse experiments, virus was either used fresh, or after column purification, glycerol was added to a final concentration of 10% (v/v), and virus was stored at -70° C. until use.
EXAMPLE 2
Enhancement of Adenovirus Mediated Gene Transfer upon Second Administration by IL-12 and IFN-γ in Mouse Lung.
The recombinant adenoviruses H5.010CMVlacZ and H5.010CBALP were used in this example. Each virus expresses a different reporter transgene whose expression can be discriminated from that of the first reporter transgene.
Female C57BL/6 mice (6˜8 week old) were infected with suspensions of H5.010CBALP (1×10 9 pfu in 50 μl of PBS) via the trachea at day 0 and similarly with H5.010CMVlacZ at day 28. One group of such mice was used as a control. Another group of mice were acutely depleted of CD4 + cells by i.p. injection of antibody to CD4 + cells (GK1.5; ATCC No. TIB207, 1:10 dilution of ascites) at the time of the initial gene therapy (days -3, 0, and +3). A third group of mice were injected with IL-12 (1 μg intratracheal or 2 μg, i.p. injections) at the time of the first administration of virus (days 0 and +1). A fourth group of mice were injected with gamma interferon (1 μg intratracheal or 2 μg, i.p. injections) at the time of the first administration of virus (days 0 and +1).
When mice were subsequently euthanized and necropsied at days 3, 28, or 31, lung tissues were prepared for cryosections, while bronchial alveolar lavage (BAL) and mediastinal lymph nodes (MLN) were harvested for immunological assays.
A. Cryosections
The lung tissues were evaluated for alkaline phosphatase expression by histochemical staining following the procedures of Y. Yang et al, cited above. The results are depicted in FIGS. 1A-1L.
Instillation of alkaline phosphatase virus (10 9 pfu) into the airway of all groups of the C57BL/6 mice resulted in high level transgene expression in the majority of conducting airways that diminishes to undetectable levels by day 28. Loss of transgene expression was shown to be due to CTL mediated elimination of the genetically modified hepatocytes Y. Yang et al, cited above!.
In the control mice, no recombinant gene expression was detected three days after the second administration of virus, i.e., day 31.
Administration of virus to the CD4+ depleted animals was associated with high level recombinant transgene expression that was stable for a month (FIGS. 1D-1F). Expression of the second virus was detectable on day 31.
Initial high level gene transfer diminished after about one month in the IL-12 treated mice; however, in contrast to the control, high level gene transfer to airway epithelial cells was achieved when virus was readministered to IL-12 treated animals at day 28, as seen in the day 31 results (FIGS. 1G-1I).
The gamma-interferon treated animals were virtually indistinguishable from the animals treated with IL-12 in that efficient gene transfer was accomplished upon a second administration of virus (FIGS. 1J-1L).
Thus, the use of these cytokines as immune modulators enabled the repeated administration of the vector without its immediate elimination by neutralizing antibody.
B. Immunological Assays--MLN
Lymphocytes from MLN of the control group and IL-12 treated group of C57BL/6 mice harvested 28 days after administration of H5.010CBALP were restimulated in vitro with UV-inactivated H5.010CMVlacZ at 10 particles/cell for 24 hours. Cell-free supernatants were assayed for the presence of IL-2 or IL-4 on HT-2 cells (an IL-2 or IL-4-dependent cell line) (Y. Yang et al, cited above!. Presence of IFN-γ in the same lymphocyte culture supernatant was measured on L929 cells as described Y. Yang et al, cited above!. Stimulation index (S.I.) was calculated by dividing 3 H-thymidine cpm incorporated into HT-2 cells cultured in supernatants of lymphocytes restimulated with virus by those incorporated into HT-2 cells cultured in supernatants of lymphocytes incubated in antigen-free medium.
The results are shown in Table 1 below.
TABLE 1______________________________________.sup.3 H-ThymidineIncorporation (cmp ± SD) IFN-γ literMedium H5.010CMVlacZ S.I. (IU/ml).sup.d______________________________________C57BL/6 175 ± 40 2084 ± 66 11.91 80anti-IL2 523 ± 81 2.98(1:5000)anti-IL4 1545 ± 33 8.83(1:5000)C57BL/6 + 247 ± 34 5203 ± 28 21.07 160IL12anti-IL2 776 ± 50 3.14(1:5000)anti-IL4 4608 ± 52 18.66(1:5000)______________________________________
Stimulation of lymphocytes from regional lymph nodes with both recombinant adenoviruses led to secretion of cytokines specific for the activation of both T H1 (i.e., IL-2 and IFN-γ) and T H2 (i.e., IL-4) subsets of T helper cells (Table 1).
Analysis of lymphocytes from the IL-12 treated animals stimulated in vitro with virus revealed an increased secretion of IL-2 and IFN-γ and a relative decreased production of IL-4 as compared to animals that did not receive IL-12 (i.e., ratio of IL-2/IL-4 was increased from 3 to 6 when IL-12 was used; Table 1).
C. Immunological Assays--BAL
BAL samples obtained from animals 28 days after primary exposure to recombinant virus were evaluated for neutralizing antibodies to adenovirus and anti-adenovirus antibody isotypes as follows. The same four groups of C57BL/6 mice, i.e., control, CD4 + depleted, IL-12 treated and IFN-γ treated, were infected with H5.010CBALP. Neutralizing antibody was measured in serially diluted BAL samples (100 μl) which were mixed with H5.010CBlacZ (1×10 6 pfu in 20 μl), incubated for 1 hour at 37° C., and applied to 80% confluent Hela cells in 96 well plates (2×10 4 cells per well). After 60 minutes of incubation at 37° C., 100 μl of DMEM containing 20% FBS was added to each well. Cells were fixed and stained for β-galactosidase expression the following day.
All cells were lacZ positive in the absence of anti-adenoviral antibodies.
Adenovirus-specific antibody isotype was determined in BAL by using enzyme-linked immunosorbent assay (ELISA). Briefly, 96-well plates were coated with 100 μl of PBS containing 5×10 9 particles of H5.010CBlacZ for 18 hours at 4° C. The wells were washed 5 times with PBS. After blocking with 200 μl of 2% BSA in PBS, the plates were rinsed once with PBS and incubated with 1:10 diluted BAL samples for 90 minutes at 4° C. Thereafter, the wells were extensively washed and refilled with 100 μl of 1:1000 diluted alkaline phosphatase-conjugated anti-mouse IgG or IgA (Sigma). The plates were incubated, subsequently washed 5 times, and 100 μl of the substrate solution (p-nitrophenyl phosphate, PNPP) was added to each well. Substrate conversion was stopped by the addition of 50 μl of 0.1M EDTA. Plates were read at 405 nm.
The results are shown graphically in FIGS. 2A through 2C, which summarize neutralizing antibody titer, and the relative amounts (OD 405 ) of IgG and IgA present in BAL samples. The titer of neutralizing antibody for each sample was reported as the highest dilution with which less than 50% of cells stained blue.
As demonstrated in the first bar of FIGS. 2A through 2C, the cytokines identified in Table 1 above were associated in the control mice with the appearance of antibodies to adenovirus proteins in BAL of both the IgG and IgA isotypes that were capable of neutralizing the human Ad5 recombinant vector in an in vitro assay out to a 1:800 dilution.
As shown in the second bar of the graphs of FIGS. 2A through 2C, transient CD4 + cell depletion inhibited the formation of neutralizing antibody (FIG. 2A) and virus specific IgA antibody (FIG. 2C) by 80-fold, thereby allowing efficient gene transfer to occur following a second administration of virus (see FIG. 2F). FIG. 2B shows a slight inhibition of IgG as well.
As shown in the third bar of the three graphs, IL-12 selectively blocked secretion of antigen specific IgA (FIG. 2C), without significantly impacting on formation of IgG (FIG. 2B). This was concurrent with a 32-fold reduction in neutralizing antibody (FIG. 2A).
The gamma-interferon treated animals (fourth bar of FIGS. 2A through 2B) were virtually indistinguishable from the animals treated with IL-12 in that virus specific IgA (FIG. 2C) and neutralizing antibody (FIG. 2A) were decreased as compared to the control animals not treated with cytokine, but not to the extent obtained with those treated with IL-12.
These studies demonstrate that the administration of selected immune modulators to recipients of gene therapy recombinant viral vectors at or about the time of primary exposure to the vector can prevent the formation of blocking antibodies and/or CTL elimination of the vector both initially and at the time of repeated exposure to the viral vector. The concordant reduction of neutralizing antibody with antiviral IgA suggests that immunoglobulin of the IgA subtype is primarily responsible for the blockade to gene transfer.
EXAMPLE 3
Enhancement of Adenovirus mediated Gene Transfer upon Second Administration by IL-12 and IFN-γ in Mouse Liver
Experiments substantially identical to those described in Example 2 above were conducted in which the location of administration of the viral vectors was the blood for introduction of the transgene into the liver, vs. the lung.
The recombinant adenoviruses H5.010CMVlacZ and H5.010CBALP were used in this example.
Female C57BL/6 mice (6˜8 week old) were injected with suspensions of H5.010CBALP (1×10 9 pfu in 50 μl of PBS) i.p. at day 0 and similarly with H5.010CMVlacZ at day 28. One group of such mice was used as a control. Another group of mice were acutely depleted of CD4 + cells by i.p. injection of antibody to CD4 + cells (GK1.5; ATCC No. TIB207, 1:10 dilution of ascites) at the time of the initial gene therapy (days -3, 0, and +3). A third group of mice were injected with IL-12 (2 μg, i.p. injections) at the time of the first administration of virus (days 0 and +1). A fourth group of mice were injected with gamma interferon (2 μg, i.p. injections) at the time of the first administration of virus (days 0 and +1).
When mice were subsequently euthanized and necropsied at days 3, 28, or 31, liver tissues were prepared for cryosections according to the procedures used above for lung tissue in Example 2.
A. Cryosection Results
The results were substantially similar for liver-directed gene therapy according to this method as for the lung-directed therapy of Example 2 above.
Administration of alkaline phosphatase virus (10 9 pfu) into the veins of all groups of the C57BL/6 mice resulted in high level transgene expression in liver tissue that diminishes to undetectable levels by day 28. Loss of transgene expression was shown to be due to CTL mediated elimination of the genetically modified hepatocytes Y. Yang et al, cited above!.
In the control mice, no recombinant gene expression was detected three days after the second administration of virus, i.e., day 31.
Administration of virus to the CD4+ depleted animals was associated with substantially lower neutralizing antibodies and high level recombinant transgene expression that was stable for a month. Expression of the second virus was detectable on day 31.
Initial high level gene transfer diminished after about one month in the IL-12 treated mice; however, in contrast to the control, some gene transfer to the liver via the blood was achieved when virus was readministered to IL-12 treated animals at day 28 and the level of neutralizing antibody was reduced.
The gamma-interferon treated animals were virtually indistinguishable from the animals treated with IL-12 in that efficient gene transfer was accomplished upon a second administration of virus.
Thus, the use of these cytokines and the anti-CD4+ antibodies as immune modulators enabled the repeated liver-directed administration of the vector without its immediate elimination by neutralizing antibody.
All articles identified herein are incorporated by reference. Numerous modifications and variations of the present invention are included in the above-identified specification and are expected to be obvious to one of skill in the art. Such modifications and alterations including the specific immune modulator selected, the manner of administration, the recombinant vector and transgene selected, route of administration, etc. are believed to be encompassed in the scope of the claims appended hereto. | A method of reducing an immune response to a recombinant adenovirus which involves co-administration of the recombinant adenovirus and a selected immune modulator. The immune modulator functions by inhibiting the formation of neutralizing antibodies and/or reducing CTL killing of the virally infected cells. The method additionally encompasses the step of re-administering the recombinant adenovirus. | 0 |
SUMMARY OF INVENTION
[0001] The invention relates to an electrical generating system which comprises a high frequency generator as one component of the system in the main power chain, and is particularly concerned with improvements to the output of such a high-frequency generator. In a preferred embodiment, the generator is a rotating permanent-magnet generator.
[0002] The principle of the invention is applicable to any such system, but in practice the invention is most valuable for systems in which the generator either rotates at high speed or has many poles, or a combination of the two, so as to produce electrical power at the generator terminals at a relatively high frequency. The best frequency is found to be a function of the rated power output of the generator. With present technology and as a very rough guideline, it may be said that substantial practical and economic benefit may be demonstrated for the invention if the product of frequency in kilohertz and rated machine power in kilowatts is of the order of a few hundred, or anywhere in a band from 100 to 1000 and perhaps higher. However, this guideline should not be taken to define limits outside which the invention is not applicable with advantage.
[0003] A particularly important example of such a generating system is known as a micro-turbine-generator, or MTG, which is designed to provide moderate amounts of power from around a few kW to a few MW. Examples of MTG applications are: to provide power to specific local loads, or to a multiplicity of points in a distribution network supplying a large number of local loads dispersed over a region, or to a parallel combination of local loads and a distribution network.
[0004] A conventional MTG system is shown and described with reference to FIGS. 1 to 3 of the accompanying drawings, in which: FIG. 1 is a circuit diagram of a typical MTG system; FIG. 2 is a cross-sectional view of a four-pole permanent-magnet generator employed in the system of FIG. 1; and FIG. 3 is a graph of generator terminal voltage versus output power for the system of FIG. 1.
[0005] [0005]FIG. 1 shows an example of a typical MTG system that comprises a prime mover in the form of a gas turbine (T), mechanically coupled to a permanent-magnet poly-phase electrical generator (G). Electrically connected to the generator is a power conditioning unit (PCU) for converting the output voltages at the terminals of the generator to the voltage waveforms required by the consumer of the generated electricity at the output of the MTG.
[0006] The power conditioning unit (PCU) may typically comprise an input stage that may be an uncontrolled rectifier stage (R) as shown in FIG. 1, in which the rectifying elements are simple diodes, followed by a DC/DC converter (C), that takes the alternator voltages as input and produces a stable DC link voltage as output. Alternatively, the input stage may embody controllable switched devices such as IGBTs in place of the diodes, and the full function may be accomplished in one step by control of the switch timing of the devices. Connected to this input stage is the output stage of the power conditioning unit which may typically be a pulse width modulated (PWM) inverter (I) plus output filter (F). The output stage takes the DC link voltage as input and produces at its output sinusoidal three-phase voltages usually of 50 or 60 Hz. FIG. 1 shows a typical configuration based on the former option for the final stage; the invention is equally applicable to either option.
[0007] It is found in the design process for any permanent-magnet generator that the machine possesses substantial internal inductive reactance, which will be denoted Xint, that affects the performance at the terminals in an important way. (Depending on the geometry of the magnets and the underlying steel rotor hub, there may, as is well known, be some difference in the values of the per-phase two-axis reactances of the machine, commonly denoted by the d-axis and q-axis values Xd and Xq respectively, this effect being known as saliency. Since saliency is typically slight in the type of machine that forms the main focus of discussion, and since Xd has the greater influence on the relevant operating circumstances, that is accordingly the value implied herein when speaking of “the reactance” of the machine.) A rotating drum-type machine, having radial magnetic flux across an annular airgap with a heteropolar permanent-magnet rotor may be taken for illustration, as shown in FIG. 2, described in detail later. This is a widely adopted configuration because of various advantages: simplicity and robustness of construction; high electrical efficiency; good achievement in terms of capability of high speed when designed with a prestressed retaining sleeve around the outer diameter of the rotor; and competitive manufacturing cost. When the design has been optimised in terms of the dimensions of the sleeve for the speed requirement, together with the proportions of the magnetic circuit to give the highest possible flux density at the airgap of the machine, and therefore the greatest possible voltage and power output at the terminals, it is common to find that the resultant steady state internal inductive reactance, when expressed in terms of the well-known per unit system (in which rated full-load voltage and current form the two bases or units for those variables, their quotient forms the base of impedance, and their product multiplied by the number of phases forms the base of power) is roughly the order of 0.4 pu.
[0008] A generator that possesses approximately such a level of reactance has a degree of reduction of terminal voltage from no-load to full load, termed voltage regulation, which can be accepted, though it is a disadvantage to the performance of the machine. FIG. 3 shows the characteristic of terminal voltage V versus output power Po, in per-unit terms, for a machine with internal per-unit reactance of 0.39 pu. The regulation at rated power may be readily determined from the usual phasor diagram (as exemplified later) for steady-state operation, and is found to be just under 12% as shown. (As shown in FIG. 3, this result includes a small percentage effect on output rms voltage due to harmonic voltages caused by a rectifier bridge that is assumed to be connected at the terminals). It should be noted that, as is well-known, rated power in the per-unit system has numerical value equal to the power factor, which in this example is 0.933. However, as can be seen from the Figure, if the power output is increased by 15% to 1.07 pu, the voltage regulation increases quite rapidly from just under 12% to about 16%. Worse still, at about 43% increase in power output above rated value (1.34 pu) the regulation is very high at about 35%, and this condition actually represents the operating limit of the machine; at that point the voltage is about to fall away to zero and no higher power level can be obtained. Any operating condition that approaches close to this limit is only marginally stable and highly undesirable.
[0009] In practical terms, allowing for variability in material properties of permanent magnets, machining tolerances on critical dimensions of the magnetic circuit, and the general desirability of having not too much voltage regulation from no-load to full-load together with reasonable stability of the voltage/power working point, it is fair to say that it is desirable to limit the internal inductive reactance to something less than 0.4 pu, and at the most about 0.45 pu, with correspondingly full-load regulation preferably not exceeding 12% and at most 14%.
[0010] The problem of internal reactance can, and generally does, place a constraint on the available power from a permanent-magnet generator, and this is for two distinct reasons. To exemplify the first constraint, suppose that a generator is designed to operate with a stipulated output power, and is found to have internal reactance of 0.45 pu. At that level of reactance the voltage regulation is around 14%, which means that the full-load output voltage is only 86% of what it was at no-load. If that drop of voltage could be avoided, so that the voltage remained approximately constant from no-load to full-load, then with the same current in the windings, the voltage-current product (which is the main determinant of power output assuming, as is typically the case, that power factor remains close to unity) would increase by ×1/0.86 or about 16%. The ohmic losses inside the machine remain the same (because current magnitude is unchanged), as do other principal components of loss, and so internal temperatures remain the same. Moreover, these losses represent a smaller fraction of the increased output power, and so machine efficiency has risen. Thus, internal reactance and consequent voltage regulation are seen to have the effect of reducing both available output power and efficiency of operation.
[0011] To exemplify the second constraint, it must first be appreciated that as rated current is increased in value, the effect is to increase the per-unit value of the internal reactance Xint, because the base of impedance has decreased due to the increase in the base of current, and therefore there is a corresponding increase in the percentage voltage regulation. In the design of a permanent-magnet generator, it may consequently turn out that the rated current has to be chosen, not to correspond to the highest permissible value that would raise internal temperatures to their highest safe levels, but rather to some lower value of current that limits the per-unit value of Xint to an acceptable level as discussed previously in relation to FIG. 3. This situation is quite commonly found to occur in the design of high speed electrical generators, particularly in the larger power sizes (say, 100 kW and up) where, due to dimensional scale effects, the proportionate heating effect of stator current in the windings tends to be less, and therefore the winding tends to run cool relative to the temperature limits set by insulation properties. Alternatively, it may be the case that the degree of internal cooling has been adjusted in design so as to allow temperatures to rise to their highest safe levels, by economising to some extent on cooling effort, but that cooling could be increased if there were the possibility of increasing the power output by so doing. In either case, it is the need to limit the effects of inductive reactance that is effectively imposing the limit on the current rating of the machine, and therefore on the rated power output, rather than the need to limit internal heating.
[0012] Thus, in general, inductive reactance may restrict the available output power from a permanent-magnet generator by two effects: firstly, by reducing the rated terminal voltage at rated current, which reduces both power output and efficiency; and secondly, by imposing a limit on the permissible current, this limit having to be accepted in order to restrict the per-unit value of the reactance to a suitable level. The first effect is always present in any machine that embodies significant internal inductive reactance. The second effect comes into play in any design in which rated current is determined not primarily by the need to limit internal heating, but rather by the need to hold the effects of reactive voltage drop down to an acceptable level. Both effects are however caused by inductive reactance being undesirably high.
[0013] The present invention concerns means for reducing or eliminating the effects of internal inductive reactance, thereby substantially increasing the permissible output power of the machine and its operating efficiency.
[0014] In accordance with the present invention, there is provided an electrical generating system comprising an AC electrical generator having an output, the system being characterised by a capacitor arrangement which is provided at the output of the generator and which is arranged so as to offset a drop of voltage from no-load to full-load occurring at the output of the generator, whereby to permit increased power to be drawn from the generator without an unacceptable drop in output voltage and without exceeding permissible temperature limits for the generator winding.
[0015] According to a preferred embodiment of the present invention, the generator is a poly-phase generator and there is provided in each output line of the generator a series capacitor, whose magnitude of capacitive reactance is so chosen as to have a substantial offsetting effect against the internal inductive reactance of the machine. Suppose that the machine has total internal effective inductive reactance per line equal to Xint. (If the machine is star-connected, then Xint equals the per-phase value of internal reactance, Xphase; if delta-connected, then by the well-known equivalence of delta- and star-connected systems it is easily seen that Xint=Xphase/3.) The capacitance value per line may be so chosen as to have a reactance Xcap approximately equal in magnitude to Xint at rated speed. Alternatively, Xcap may be chosen to be less than but a substantial fraction of Xint at rated speed, or it may (with due caution to avoid generating excessive voltages) be chosen to be somewhat greater than Xint. Considerations influencing this choice are discussed later.
[0016] Assuming that the capacitance value has been so sized as to counter-balance substantially the internal inductive reactance at rated speed, then the net series reactance in the line, which is now (Xint−Xcap), is much smaller than the previous value, Xint. The machine/capacitor combination behaves as though it were a simple generator with small internal reactance. Thus, the voltage at the terminals of the combination remains substantially constant from no-load to full-load. Moreover, if the power output of the machine is increased above its previous rating, the voltage remains approximately constant. It will be clear that both the constraints on power, discussed previously, have been removed. There is negligible loss of power output capability due to terminal voltage falling with load, and current is not constrained by the need to limit inductive reactive voltage drop within the machine to an acceptable level. Power losses in the external capacitors are very small, and efficiency accordingly improves as the power output is increased.
[0017] The attractiveness of this technique owes much to the superior performance of modern metallised-film capacitors. These can be made quite cheaply, and can offer a uniquely good combination of the following properties: capacitance per unit volume; ripple current tolerance; voltage withstand; long life; acceptability of case temperature in the order of 70° C. Use of the capacitors typically does not compromise the life of the equipment, and their cost may be considerably less than the extra cost of alternatively building a larger alternator to offer the same increase of power without capacitors—thus the cost per kilowatt of generated power is reduced. Moreover, it is readily possible to have capacitors designed and manufactured in moderate numbers to match, within the constraints of present technology, any specific application in terms of capacitance value and current and voltage ratings, without incurring a large cost penalty.
[0018] In this regard, it may be noted that the voltage rating of the capacitor is determined by the current through it, l, and the highest value of IXint voltage drop that can consequently occur across it in service; it needs to be typically only a fraction of the rated phase voltage of the machine. It is the limits to the physical properties of the capacitors that can be manufactured with metallised film technology that give rise to the preferred relationship between electrical frequency and machine power rating, that was indicated earlier. Particularly significant here is the way in which these limits of manufacturing technology cause capacitor current rating to be effectively linked to capacitance value, and hence restrict the way in which the ohmic (non-pu) value of Xint is related to current at a particular frequency.
[0019] As a useful guideline, it typically turns out in many cases that the apparent power rating of the total capacitor bank used with the machine may be up to about half its real power rating.
[0020] Clearly, by setting the inductive and capacitive reactances approximately equal at rated speed, a resonance condition (where the two reactance values are precisely equal although, of course, opposite in sign) is being established near to rated speed, and it is natural to inquire whether this produces any over-voltage or over-current effects, as are commonly encountered with resonance phenomena in other applications, that might be troublesome. However, this is a series resonance (because in the preferred embodiment the inductive and capacitive reactances are connected in series) as opposed to a parallel resonance, and consideration shows that in this case no over-voltage effects occur at resonant frequency, nor is there any over-current since current is controlled by the demand load connected to the complete generating system. Moreover, higher harmonic currents that are drawn from the generator by non-linear loads, such as a rectifier bridge, are negligibly affected, since the impedance to these currents is dominated by the internal inductive reactance of the machine, the capacitive reactance being small at the higher frequency.
[0021] One feature that calls for consideration at the design stage is operation at reduced speed. A moderate degree of speed reduction at rated power generally does not pose any problem. However, as speed and frequency reduce, capacitive reactance increases, and it is necessary to check that the voltage drop across the capacitor is not exceeding its permissible value due to the current passing through it. In this regard, the MTG application is particularly well suited. It is common practice to start the MTG set using the generator in motor mode to accelerate the shaft up to a speed at which the turbine can become self-sustaining, which typically occurs at around 40% rated speed. As part of the switching operations to establish the motoring mode, it is convenient to switch the capacitors out of circuit, switching them back in when the mode changes over to generating. At the lower end of the speed range above this changeover point, the turbine has very restricted capability to generate power. Consequently, high line currents at low speed are not experienced. It is typically found with an MTG system that if the capacitor is rated for voltage in accordance with the highest IXcap voltage drop that occurs in any defined operating condition at or near rated speed, then no other condition occurs during start-up or other transient circumstance that calls for a higher rating.
[0022] The operating power factor of the machine/capacitor combination is the same as for the machine alone, being determined by the characteristics of the connected load. However, the phase relationship between voltage and current at the machine terminals is changed by the addition of capacitors, and the magnitude of machine voltage on load is generally increased as a result. Without capacitors, this phase relationship generally gives a power factor of around 0.93 or better; with the capacitors added, the power factor typically improves. Detailed study shows the voltage at the machine terminals in any likely operating condition typically to be less than the rated no-load voltage of the machine.
[0023] The inclusion of the capacitors reduces the total series impedance in the output lines of the generator to a very low level. Consequently, any short circuit at or near the terminals of the machine/capacitor combination will cause an extremely high current that burns out the windings very rapidly. To protect the machine against such an external short circuit, it may be preferable to provide fuses or switches in its output lines with appropriate l 2 t characteristic, so that thermal capacity can limit internal temperature rise to a safe level.
[0024] It is often satisfactory to size the capacitance value so that capacitive reactance compensates most but not all of the inductive reactance, and voltage regulation at the output terminals is reduced to a few percent. By reducing the capacitance and so increasing reactance, an approximately level voltage characteristic can be obtained. In general, it is found to be perfectly permissible to reduce capacitance still further so that there is a moderate degree of rise of voltage at the generator/capacitor output terminals. This can be used to offset the fall of voltage with load that typically occurs across a following rectifier stage, so that the final output DC voltage is substantially constant, independent of load. It may thus be possible to avoid the cost and extra losses associated with a further DC/DC converter, which would otherwise typically be needed to maintain a controlled, constant DC voltage. However, in the MTG case for example, it is common to design for some variation of speed with load, so as to optimize the efficiency of the turbine on part load. In that case, the provision of a constant DC level for all operating conditions simply by suitably sizing the capacitance is not possible.
[0025] Preferred features of the generating system according to the present invention are set out in the following paragraphs.
[0026] According to these preferred features, a permanent-magnet AC electrical generator has capacitors connected in series in one or more of the output lines of the generator, the value of capacitance being so chosen that the drop of voltage from no-load to full-load that would occur at the terminals of the machine without the effect of the capacitors is substantially offset in respect of the voltage occurring at the output terminals of the capacitors, thus permitting increased power to be drawn from the machine/capacitor combination without unacceptable drop in output voltage and without exceeding permissible temperature limits for the machine winding.
[0027] The permanent-magnet AC electrical generator may be a poly-phase AC generator, with the capacitors connected in series in each of the poly-phase output lines.
[0028] Advantageously, the electrical generator operates at a fairly high frequency such that the combination of required capacitance value and required voltage rating and current rating of the capacitor forms a good match to what is naturally available with metallised film or other high-output capacitor technology, thus enabling the cost of the capacitors per kW of increased power output to be advantageously less than the saved cost per kW in the generator by virtue of its reduced size for the given power rating.
[0029] For example, the generator may be driven either directly or through gearing by the turbine in a micro-turbine-generator system.
[0030] In the preferred embodiment, the machine/capacitor combination is connected to a rectifier bridge and the capacitance value is so chosen that the DC output voltage from the rectifier bridge varies approximately in a required manner with variation of load. For example, the capacitance value may be so chosen that the DC output voltage from the rectifier bridge is substantially constant, independent of the load.
[0031] One possible advantage of the use of such capacitors is to enable a smaller electrical machine for the given power rating to be fitted into a smaller void space than would be possible or convenient without the use of the capacitors.
[0032] The invention at least in its preferred form described below thus provides an arrangement for obtaining greater power from a permanent-magnet generator, with improved efficiency and in may cases lower cost per generated kilowatt, by connecting capacitors in series with the poly-phase output lines of the generator. The arrangement shows greatest benefit in, but is not in principle restricted to, generators that produce their output power at fairly high frequency, defined by the relationship f (in kilohertz) multiplied by rated power (in kilowatts) is close to or greater than 100.
[0033] Consequently, a particularly important application of the invention is to micro-turbine-generators, where power output can usually be increased by at least 15%, and quite often by up to 35% or even more. The value of capacitance must be appropriately chosen, so as substantially to offset the adverse effects of internal inductive reactance, and power output is consequently increased due to two distinct effects. Firstly, the voltage at the terminals of the machine/capacitor combination shows little or no voltage drop from no-load to full-load, differing from the action of the machine alone, where substantial voltage drop occurs. The power output of the combination is correspondingly greater for the same generator current magnitude. Secondly, it is no longer necessary to restrict the value of rated current in order to hold the aforesaid voltage drop at an acceptable level. If this restriction was previously causing the machine to be rated at a current magnitude less than that which could be tolerated on grounds of internal temperature rise alone, then it now becomes possible to up-rate the current and so further increase power output.
BRIEF DESCRIPTION OF DRAWINGS
[0034] The invention will now be described by way of example only and with reference to the accompanying drawings, in which:
[0035] FIGS. 1 to 3 show a conventional MTG system, as discussed above;
[0036] [0036]FIG. 4 is a circuit diagram showing a modification of the system of FIG. 1 in which the generator is formed as a star-connected generator with series connected capacitors;
[0037] [0037]FIG. 5 is a phasor diagram for the generator of FIG. 4 including the series connected capacitors; and
[0038] [0038]FIG. 6 is a phasor diagram for the generator of FIG. 1 without the series connected capacitors.
DETAILED DESCRIPTION
[0039] Referring firstly to FIG. 2, this shows a cross section of an electrical generator rated 84 kW output power at 80,000 r/min, for use in an MTG system as shown in FIG. 1. A stator lamination ( 1 ) is provided with 24 slots ( 2 ) into which is inserted a 3-phase, 4-pole winding (not shown). A prestressed cylindrical sleeve ( 3 ) which may be made of inconel or carbon fiber retains four rare-earth permanent-magnet rotor poles ( 5 ) which are bonded to an inner steel hub ( 6 ). Interstices under the sleeve between magnets contain epoxy filler ( 7 ). Between the stationary stator and the rotating sleeve there is a radial airgap ( 4 ). The stator is cooled by a close fitting water jacket (not shown) surrounding the OD laminations. Air cooling may be supplied axially along the airgap as necessary to control principally the operating temperature of the rotor.
[0040] Principal design details (all dimensions in mm) are as follows: outer diameter of stator lamination=105.0; diameter to slot bottoms=80.0; diameter at stator bore—60.6; diameter over sleeve=59.6; diameter over magnets=51.3; width of square hub=34.5; width of main part of tooth=4.2; slot opening=2.2; axial length (not shown) of laminated core and magnets=125.0.
[0041] Stator winding comprises: 24 coils in 2-layer form; the coils of one phase connected to form two parallel paths; each coil wound with 3 series turns; stator conductor=19 strands of 25 American Wire Gauge (AWG) enamelled wire. Insulation specification permits 180° C. maximum winding temperature. Coolant inlet temperature=50° C.
[0042] A person skilled in the art of electrical machine design may verify the following: the machine generates 298 rms V/phase on no-load; total inductance on the d-axis=57.8 μH/phase, giving reactance=0.968 ohms/phase at an electrical frequency=2.67 kHz; when delivering 84 kW output power into an uncontrolled 3-phase rectifier bridge the terminal voltage falls to 260 rms V/phase, current=117 rms A/line; per-unit impedance base=2.23 ohms; per-unit x-axis reactance=0.434 pu; voltage regulation=13.5%; efficiency=97.8%; with 0.1 litre/sec of water flow and adequate supply of air to the airgap the maximum temperature in the winding=155° C.
[0043] This machine therefore represents an example towards the high-regulation end of the advisable range recommended earlier, having reactance of 0.434 pu (close to the advisable limit of 0.45 pu) and regulation correspondingly of 13.5% (close to the advisable limit of 14%). Clearly, with this machine, it would not be advisable (or indeed, possible) to increase the power rating significantly. Note, however, that the winding temperature is comfortably less than the maximum of 180° C. that is in fact permissible according to the insulation specification. This is a machine, therefore, that suffers from both the effects described earlier: the drop of voltage on full load substantially reduces the available power, and the current cannot be increased further to take advantage of the permissible maximum temperature because it will bring the operating point too close to the absolute power limit that is depicted (for a slightly lower value of per-unit reactance) by the curve of FIG. 3.
[0044] In accordance with the invention, capacitors may now be introduced as shown in FIG. 4. The general arrangement shown in FIG. 4 depicts the generator (G) and rectifier stage (R) of FIG. 1, assuming for example a star connected generator, and shows series capacitors (Ca) added.
[0045] In the example of FIG. 4, capacitance value is 80 μF/line, rated 150 rms V max, ripple current=150 rms A max, permissible case temperature=70° C., 100,000 hour life minimum at fully rated condition, considerably more if running cooler. The choice is now made to increase the power output of the machine by 25% to 105 kW. Again, a person skilled in the art of electrical machine design may verify the following: no-load voltage and inductance in μH/phase unchanged; when delivering 105 kW output power into an uncontrolled 3-phase rectifier bridge the terminal voltage of the machine/capacitor combination falls to 294 V/phase; current=129 A/line; voltage regulation=1.4%; efficiency=97.9%; maximum temperature in the winding=173° C.
[0046] This arrangement is now producing 25% more power out of the same machine. Voltage regulation is almost negligible, efficiency has slightly improved, and winding temperature is still comfortably within specification. In other examples, it is possible to demonstrate an even greater percentage increase in output power, more marked improvement in efficiency, and generally lower temperature rises than are characteristic of this case.
[0047] The phasor diagram in FIG. 5 depicts this operating condition, for the fundamental sinusoidal components of voltage and current. (Minor apparent discrepancies in quoted numbers and between numbers and diagram are due to second order effects introduced by voltage and current harmonics and saliency.) The quantities Vcap and Vind are the voltages dropped across the capacitor and across the internal machine inductance, respectively, Vterm is the output terminal voltage of the machine/capacitor combination, Vmc is the voltage at the terminals of the machine, and Vnl is the particular value of Vmc on no-load. Phasor relationships are: Vind=j l Xint; V cap=−j l Xcap; Vterm=Vnl−(Vind+Vcap); Vmc=Vnl=j l Xint. It will be clear that the output voltage is similar in magnitude to the no-load voltage when the capacitors are present, showing almost negligible reduction (low voltage regulation). Also it can be seen that the voltage at the machine terminals is similar in magnitude to the no-load voltage, again showing a small reduction, and that the phase angle between Vmc and I is small, giving an internal power factor (equal to the cosine of this angle, neglecting minor harmonic effects in the current and voltage waveforms) that is close to unity.
[0048] [0048]FIG. 6 shows the situation if the capacitors are removed and it is attempted to work still at 105 kW. Vmc (which now is the same as Vterm) is much reduced at 228 V (high regulation). The current I increases to the unacceptably high value of 166 A, which will rapidly over-heat the machine, and Vind is increased correspondingly. A further important point, not immediately apparent from inspecting the diagram, is that this operating condition is not undesirably close to the absolute limit of power output.
[0049] The following discussion makes clear why a value of frequency appropriately related to power rating is to be preferred. If the power, voltage and current data were as specified above, but related to a 4-pole machine running at only one tenth speed=8,000 r/min, for the sake of argument, then 10 times as much capacitance would clearly be required. This might be achieved by having 10 units in parallel of the same capacitor as before, which would cost 10 times as much and offer 10 times the current capability—which is not called for in this example. Current capability is being wasted, and the cost of capacitors per kW of power rating is therefore multiplied by 10, and that would probably exceed the saving in cost achieved by the reduced size of the machine for the given power. Alternatively, the increased capacitance might be achieved in a single larger unit, which would tend to be about 10 times the volume and again roughly 10 times the price, but because of connection difficulties would not offer so much increase in current rating. Considerations of this kind lead to the general conclusion that, for the greatest advantage, the frequency must be sufficiently high so that the combination of capacitance, voltage and current ratings, tend to match well to the natural optimum of what can be achieved by metallised film capacitor technology for the given ratings. In this regard, MTG units tend to be an example of a particularly good match, and the cost savings achieved by applying the invention in this embodiment are very substantial.
[0050] However, each case must be judged on its merits. The embodiment above is described by way of example and is only to be considered preferred and illustrative of the inventive concepts disclosed. The scope of the invention is not to be restricted to the embodiment. Various and numerous other arrangements may be devised by one skilled in the art without departing from the spirit and scope of this invention.
[0051] For example, the above description relates to an embodiment that includes a series connection for the capacitors, but an alternative possibility is to connect capacitors across the machine terminals in parallel with the external load. This can achieve improvement in voltage regulation and output power capability in a manner that is similar in principle to the action of series capacitors. However, there are features of the parallel connection that may be less desirable in a practical embodiment. In particular: a substantial increase occurs in the terminal voltage of the machine/capacitor combination at no-load (whereas series capacitance has no effect in this condition), and the machine may need to be re-designed in order to bring this voltage down to a desirable level; the effectiveness of the added capacitors tends to decrease with increase of load basically because the magnitude of the capacitor current that is being drawn through the machine is becoming smaller relative to the magnitude of the demanded load current (whereas the effectiveness of series capacitors is sustained well up to high load levels as has been discussed); it may typically be found that the combined voltage/current/frequency requirements for parallel capacitors do not match as well to what is available within the limits of manufacturing technology, compared with the requirements for series capacitors. However, with some system specifications, it may nonetheless be possible that the parallel configuration is to be preferred. | The invention provides an electrical generating system comprising an AC electrical generator (G) having an output, and a capacitor arrangement (Ca) provided at the output of the generator and arranged so as to offset a drop of voltage from no-load to full-load occurring at the output of the generator. As described, the generator (G) is a permanent-magnet generator having a plurality of terminals and associated output lines, and the capacitor arrangement comprises a respective capacitor (Ca) connected in series in each of the output lines, with the value of the capacitance of each capacitor being selected such that a drop of voltage from no-load to full-load occurring at the associated generator terminal is substantially offset at an output terminal of each said capacitor. | 8 |
BACKGROUND OF THE INVENTION
The present invention relates to a tripod to which a compact camera is provided in photographing, and more particularly to a compact tripod for use in a camera which is used for photographing on a table and the like.
The tripod for use in a compact camera has a screw member to fix a camera, on the upper surface of its supporting unit (which is called a universal head) so that the camera is fixed to the supporting unit by the screw member. Three adjustable legs are provided to the downward surface of the supporting unit that is used for supporting legs. The tripod is used in such a manner that: the legs are extended so that the leg positions can be located at the tops of a triangle formed on the ground; the length of the leg is adjusted so that the center of gravity of the camera can be placed inside the triangle; the tripod is installed on the ground; and further the tripod is adjusted while a photographer is looking into a viewfinder.
There is a tripod having flexible legs which are composed in such a manner that the three legs of the tripod can be freely folded. In this case, the actual length of the legs and the positions of the tops of the tripod are adjusted by folding the legs of the tripod so that the camera can be set at a suitable photographing position.
The tripod for use in a compact camera has a simple structure. However, it is not necessarily easy to set a tripod provided with a camera at a suitable photographing position. When a camera provided to a tripod is inclined, the horizontal line on the photographed picture is also inclined and the portrait is inclined, too, which is not desirable. When a photographer takes a photograph while holding a camera in his hands, he unconsciously holds the camera horizontally. However, when a tripod is used, the photographer must adjust the length of the tripod legs and the leg positions so that the camera ca be set horizontally.
SUMMARY OF THE INVENTION
The object of the present invention is to provide a tripod for use in a camera by which the camera can be set horizontally without any difficulty.
The above-described object can be accomplished by a tripod for use in a camera which is characterized in that: a screw member is provided to the upper surface of the supporting unit; a central leg composed of a flexible member is provided to the downward surface of the supporting unit; and two side legs are symmetrically provided to both sides of the central leg, wherein the side legs can be opened to the stop position and the length of the side legs is shorter than that of the central leg.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 and FIG. 2 are drawings which show the appearance of the tripod of the present invention.
FIG. 3 is a sectional view of the main portion of the tripod of the present invention.
FIG. 4 is a drawing which shows the appearance of an automatic release camera.
FIG. 5 to FIG. 10 are plan views and sectional views of the main portions of the above-mentioned camera.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The tripod for use in a camera of the present invention, which will be explained in an example, combines the function of a tripod for use in a common compact camera and the function of a tripod for use in an automatic release camera provided with the panning function which will be explained later, so that panning photography can be taken using the tripod. At the outset, the function of a tripod for use in a common camera by which stationary photography is taken, will be explained as follows.
The tripod for use in a camera of the present invention is illustrated in FIG. 1, FIG. 2, and FIG. 3.
The above-described tripod is composed of: the supporting unit 10 on which a camera is positioned and fixed; the flexible central leg 20 which is fixed to the center of the underside of the supporting unit 10; and the side legs 21 which can be opened to the outside stop position symmetrically with regard to the central leg 20.
The above-described central leg 20 is formed in such a manner that a metal strip is wound spirally, so that the central leg 20 can be composed of the member having flexibility and adequate stiffness, and the upper end of the central leg 20 is fixed to the under side of the above-described supporting unit 10. On the other hand, the above-described side legs 21 are made from hard synthetic resin, and the upper ends of the side legs 21 are rotatably provided to the under side of the supporting unit 10 by a widely known pivotal mechanism so that the side legs and the above-described central leg 20 can form isosceles triangle. The upper end of the central leg 20 may not be fixed to the under side of the supporting unit 10, but it may be rotatably provide it to the under side of the supporting unit 10 by the widely known pivotal mechanism in the same way as the side legs 21.
The above-described tripod is used in such a manner that: a screw member to hold a camera, which will be described later, is screwed to a screw provided to the bottom portion of the camera so that the camera can be fixed to the supporting unit 10; then the above-described side legs 21 are symmetrically opened to the outside stop position as illustrated in FIG. 2 and by this mechanism the camera can be automatically held horizontally; on the other hand the camera angle in the vertical direction can be freely adjusted when the elevation angle of the camera is adjusted by bending the above-described central leg 20 adequately; and further the rubber cap 22 is provided to the lower end of each leg so that each leg can not slip from the setting position.
Consequently, according to the above-described tripod, the horizontal angle of a camera can be automatically determined only by opening a pair of side legs 21, and the elevation angle of the camera can be freely controlled by adjusting the bend of the central leg 20 without changing the horizontal state of the camera, so that the camera angle to an object can be very easily and quickly adjusted.
The figures illustrated in FIG. 1 show the size of each portion of an example of a tripod that is suitable for a light compact camera to which a 35 mm roll film is applied, for example. In order to adjust the camera position, it is preferable that the length of the side legs 21 is shorter by 10% than that of the central leg 20.
FIG. 3(A) is a sectional view of the above-described supporting unit 10 taken on line A--A of FIG. 1.
The above-described supporting unit 10 is integrally composed of the upper member 11 on which a camera is placed and of the lower member 12 to which the above-described central leg 20 and the side legs 21 are provided. The above-described upper member 11 is fixed to the above-described lower member 12, while the above-described screw member 13 is contained in the cut-out portion 12A located at the center of the lower member 12, and the screw member 13 can be raised and lowered in the cut-out portion 12A.
The engagement pin 14 is buried at a predetermined position on the upper surface of the upper member 11, the axial line of the engagement pin 14 is parallel to the axial line of the above-described screw member 13, and the top portion of the pin 14 is always protruded from the upper surface of the upper member 11 by the action of a built-in compression spring.
The side 10A of the supporting unit 10 to which the above-described engagement pin 14 is provided, is labeled "PAN" and the opposite side 10B is labeled "FIX".
The above-described screw member 13 is integrally composed of: the screw portion 13A which is engaged with the set screw of a camera; the body 13B; and the knob 13C for use in rotation. A common camera is set on the supporting unit 10 in such a manner that: the knob 13C is rotated while it is pushed upward so that the screw member 13A ca be engaged with the set screw of the camera placed on the supporting unit 10; and finally the camera is fixed to the supporting unit 10 when the upper member 11 of the knob 13C comes into contact with the bottom surface of the camera. In this case, the above-described engagement pin 14 is pressed by the bottom surface of the camera and is buried in the upper member 11 as illustrated in FIG. 3(B).
When an automatic release camera having a mechanism shown in FIG. 4 to FIG. 10 is provided to the tripod of the present invention, it is possible to conduct automatic panning photography, so that extensive and various photography can be realized.
FIG. 4 shows the appearance of the above-described automatic release camera, and this camera has the function of detecting the input voice and the function of conducting the release operation when the detected voice satisfies a predetermined condition.
In FIG. 4, the numeral 1 is a camera lens, the numeral 2 is a viewfinder, and the numeral 3 is a monitoring window to range a photographing object, wherein the monitoring window is installed in order to watch the object from the upper position when the camera is provided to the above-described tripod. The numeral 4 is a release button which is used in ordinary photography. The numeral 5 is an automatic release lever. A group of LEDs 6 to display the sound pressure level are provided on the front side. When the automatic release lever is slid upward or downward, the microphone hole 5a behind which a microphone is provided is opened and closed, and when the microphone hole 5a is exposed, the automatic release is changed over so that photographing can be automatically conducted by a voice.
FIG. 5 is a drawing which shows the arrangement of the panning mechanism and other units. In the drawing, like reference numbers designate corresponding parts throughout FIG. 4 and FIG. 5, and the explanations will be omitted.
In the drawing, the numeral 41 is a reel to wind a film. The numeral 42 is a reel chamber. The numeral 43 is a winding mechanism which is driven by the motor 27, and the reel 41 is rotated by the winding mechanism 43 in the winding direction. The numeral 45 is a panning mechanism which is driven by the motor 27. The numeral 46 is a screw for setting the camera on the tripod which is a camera supporting means. The numeral 48 is a lens holder which holds the camera lens 1. The numeral 49 is a film rewinding shaft which engages with the winding shaft of a film magazine. The numeral 50 is a film rewinding mechanism which rotates the rewinding shaft 49. The film rewinding mechanism 50 is driven by the motor 27. The numeral 51 is a film magazine chamber. The numeral 52 is a battery chamber.
FIG. 6 is a bottom plan view which shows the composition of the winding mechanism 43 and the rewinding mechanism 50.
In the drawing, the numeral 61 is a motor gear unit which reduces the rotation speed of the motor 27. The torque is transmitted through the motor gear unit 61 to the drive gear 62. The drive gear 62 is composed as illustrated in FIG. 7, and the winding planetary gear 63 is frictionally connected with the winding planetary shaft 65 under the function of the frictional spring 64. The winding planetary shaft 65 is provided to the winding planetary lever 65a, and the winding planetary lever 65a is rotatably provided to the drive shaft 62a which is the center shaft of the drive gear 62. When the drive gear 62 is rotated counterclockwise in the drawing, the winding planetary gear 63 engages with the reel 41 and gives torque to the reel 41, so that the reel 41 is rotated in the direction of film winding (counterclockwise).
On the other hand, when the drive gear 62 is rotated clockwise, the winding planetary gear 63 itself is rotated clockwise around the drive gear 62, and the gear 63 engages with the first rewinding gear 66 and transmits torque to the gear 66. The first rewinding gear 66 rotates the rewinding shaft gear 72 through the rewinding gear train 67 to 71. The rewinding shaft 49 is rotated clockwise in this way so that the film can be rewound.
FIG. 8 is a bottom plan view which shows the panning mechanism 45.
The drive gear 62 is engaged with the oscillating planetary gear 73 which has the same composition as the winding planetary gear 63. Namely, the oscillating planetary gear 73 is frictionally connected with the oscillating planetary shaft 75 under the function of the frictional spring 74 (Refer to FIG. 7.). When the drive gear 62 is rotated counterclockwise, the oscillating planetary gear 73 itself is rotated counterclockwise around the drive gear 62, and it engages with the first oscillating gear 76 and transmits torque.
The oscillating planetary gear 73 is provided to the oscillating planetary lever 77. When the oscillating planetary lever 77 is moved by the changeover lever 78 in the direction of an arrow in the drawing, the oscillating planetary gear 73 is disengaged from the first oscillating gear 76, so that the oscillation can be stopped. The changeover lever 78 is connected with the lens holder 48. When the automatic release lever 5 is slid downward (turned off), the lens holder 48 is rotated counterclockwise by the lever 5 and the oscillating planetary lever 77 is pushed by the changeover lever 78, so that oscillation can not be conducted. When the automatic release lever 5 is slid upward (turned on), the restriction by the changeover lever is released and oscillation can be conducted.
The first oscillating gear 76 is a two step gear and transmits torque to the second oscillating gear 79 which is also a two step gear so that the speed is further reduced, and the third oscillating gear 80 is rotated.
The third oscillating gear 80, the arm 81, and the oscillating lever 82 has a crank mechanism, and when the third oscillating gear 80 is rotated, the oscillating lever 82 conducts oscillating motions. As illustrated in FIG. 9, the oscillating lever 82 is frictionally connected with the tripod setting screw 46 under the function of the frictional spring 83. The tripod setting screw 46 is rotatably provided to the camera body 85 by the long screw 84. Accordingly, when the oscillating lever 82 is activated, the tripod setting screw 46 is oscillated.
FIG. 10 shows the bottom of a camera. The flange 46A is integrally provided to the edge portion of the above-described tripod setting screw 46, and the tripod screw 46 is oscillated in the space formed by the cut-out portion 90A of the camera bottom cover 90.
The edge surfaces of the above-described flange portion 46A and the cut-out portion 90A are provided with the cutout K1 and the cutout K2 which engage with the engagement pin 14 provided to the supporting unit 10 of the tripod.
The above-described cutout K1 and k2 are located on the line which is parallel with the optical axis of the camera lens 1 and which passes through the axial center of the tripod setting screw 46, wherein the cutout K1 and K2 are symmetrically located with regard to the tripod setting screw 46.
The relation between the above-described tripod setting screw 46 and the bottom cover 90 is illustrated in FIG. 9. The tripod setting screw 46 and the flange 46A which is provided to its edge portion, are protruded from the opening 91 of the bottom cover 90 and contained in the space of the above-described cut-out portion 90A.
When a camera is provided to the supporting unit 10 of the tripod, a small gap is formed between the upper surface of the supporting unit 10 and the above-described flange 46A, and between the upper surface and the bottom cover 90, so that the tripod setting screw 46 and the bottom cover 90 of the camera body, can be respectively rotated with regard to the tripod. However, the oscillating motion of either the tripod setting screw 46 or the camera body ca be restricted according to the engagement of the cutout K1 or the cutout K2 and the engagement pin 14 of the supporting unit 10.
Since the tripod setting screw 46 is engaged with the above-described screw member 13 of the tripod a illustrated in FIG. 9, the camera is rotatably connected with the tripod. When the engagement pin 14 is engaged with the cutout K1 which is provided to the flange 46A of the tripod setting screw 46, the rotation of the tripod setting screw 46 is restricted by the tripod, so that the camera itself is panned by the reaction force within a predetermined range of rotation angle. At this moment, the front side of the camera, which is the lens side of the camera, faces the side of the supporting unit 10 on which "PAN" is labeled, so that the state that the camera is panned can be indicated.
On the other hand, when the engagement pin 14 is inserted into the cutout K2 provided to the bottom cover 90 of the camera, the rotation of the camera body is restricted. As a result, the tripod setting screw 46 is oscillated integrally with the screw member 13 of the tripod. In this case, the front side of the camera faces the side of the supporting unit 10 on which "FIX" is labeled, so that the state that the camera is not panned can be indicated.
The reason why the panning lever 82 is frictionally connected with the tripod setting screw 46, is to protect the gear train from receiving a strong force. At the frictional portion, the stopper 86 is provided in order to prevent the tripod setting screw 46 from idle running when the tripod setting screw 46 is set at the tripod.
The output of a film feed detecting device, which is not illustrated in the drawing, is sent to the CPU, and when the CPU detects that a film is wound up one frame portion, the motor 27 is stopped. Accordingly, the camera panning is also stopped. As the diameter of the reel 41 as winding a film is increased, the rotation angle of the reel in each case the film is wound up one frame portion, is decreased gradually and the running time of the motor 27 is also decreased. Consequently, the panning angle of the camera is randomly varied according to the crank mechanism and the running time of the motor 27, wherein the crank mechanism is composed of the third oscillating gear 80, the arm 81, and the oscillating lever 82. When a drive means which is not used while exposure operation is conducted, such as the film winding motor, the AF lens controlling means, the lens focus changing means, and the like, is used for panning the camera, an electrical or mechanical particular means to prohibit camera panning is not needed, and further the start signal and the stop signal of the changing means are not particularly needed, and furthermore the circuit composition becomes simple.
The numeral 87 is a stopper having the function of a fail-safe which works in the case the friction mechanism of the panning lever 82 and the tripod setting screw 46 is out of order. The moving of the film while exposure is conducted can be prevented by the stopper 87, wherein the moving of the film position is caused as follows. When the tripod is set at the camera, the external force is transmitted to the rewinding mechanism through the gear train, so that the film is forced to move.
Namely, assuming that the frictional mechanism does not work, the external force to squeeze the tripod is directly transmitted to the third oscillating gear 80 and the third oscillating gear 80 is rotated clockwise or counterclockwise according to the positional relation between the gear 80 and the arm 81. Assuming that the third oscillating gear 80 is rotated clockwise, the first oscillating gear 76 is also rotated clockwise and the force is transmitted to the oscillating planetary gear 73 so that the drive gear 62 is also rotated clockwise. For that reason, the winding planetary lever 65a is rotated clockwise around the drive gear 62, and the winding planetary gear 63 is forced to move in the direction of the first rewinding gear 66. However, the rotation of the winding planetary lever 65a is stopped by the stopper 87, so that the winding planetary gear 63 is not engaged with the first rewinding gear 66. Therefore, even when the frictional mechanisms of the oscillating lever 82 and the tripod setting screw 46 are out of order, the film is not mistakenly rewound by the force given from the outside when the tripod is set.
When the third panning gear 80 is rotated counterclockwise by the external force, the first oscillating gear 76 is also rotated counterclockwise and the oscillating planetary gear 73 is departed from the first oscillating gear 76, so that the external force is never transmitted to the rewinding mechanism 50.
The tripod for use in a camera of the present invention can be used not only for an ordinary camera but also for a camera in which the release operation can be controlled by the signal sent from various kinds of sensors such as an infrared sensor, a heat sensor, and the like so that panning photography and other various photography can be conducted.
In this example, the leg length of the tripod is fixed, however the present invention can be applied to a tripod, the legs of which can be extended. In this case, the length of both legs must be the same, so that it is desirable that the legs are marked in order to prescribe the length of extended legs.
According to the present invention, a useful tripod for use in a camera which is widely used in various fields, can be provided, wherein the tripod is characterized in that: the camera position with regard to a photographic object can be easily adjusted; not only an ordinary camera but also a special camera having the panning function can be provided to the tripod; panning photography or stationary photography can be selected only by resetting the camera; and the camera can be held horizontally and panning photography can be performed while it is held horizontally. | The invention provides a tripod for use with a camera by which the camera can be set horizontally without any difficulty. The tripod includes a supporting base for supporting a camera thereon through screw mechanism. On the lower surface of the base is provided a central leg composed of a pliantly bendable rod like member. On both the sides of the central leg are symmetrically provided a pair of side legs, each of which is adapted to pivotally open in outwardly slanting direction to a stop position and is shorter than the central leg. | 5 |
CROSS-REFERENCE TO RELATED PATENT APPLICATIONS
The present application claims priority to Great Britain Application No. 0611249.4, filed Jun. 7, 2006, the specification, drawings, claims and abstract of which is incorporated herein by reference in its entirety.
FIELD OF THE INVENTION
This invention relates to the communication of data, and particularly to a method for communicating data over asymmetric channels.
BACKGROUND OF THE INVENTION
This section is intended to provide a background or context to the invention that is recited in the claims. The description herein may include concepts that could be pursued, but are not necessarily ones that have been previously conceived or pursued. Therefore, unless otherwise indicated herein, what is described in this section is not prior art to the description and claims in this application and is not admitted to be prior art by inclusion in this section.
A variety of protocols are available for the communication of a data message over a communications link. In numerous protocols the message is divided into packets at the transmitter end; the packets are conveyed individually over the communications link; and at the receiver end the packets are combined to re-form the message. Each packet normally comprises a payload, which represents the portion of the message that the packet carries, and control data, which is carried in the packet
One example of a packet protocol is TCP (transmission control protocol). This protocol is widely used as the transport layer protocol in internet communications. The performance of TCP is however significantly reduced in asymmetric data communication systems, wherein a forward channel carries information at much higher speed than a reverse channel.
One such asymmetric system is the DVB-H (Digital Video Broadcasting via Handheld Terminals) system. DVB-H is used to provide high quality video broadcasting services to hand held terminals. It has also been proposed to use DVB-H for downloading game data to hand held devices. DVB-H uses a downlink channel which can transport data from a server to a device at speeds high as 5-30 Mbit/s. When using TCP it is necessary to send acknowledgement packets (ACK) from the device to the server for every data packet received on the downlink channel. The server will only continue to send data upon receipt of ACK packets. The ACK packets are transmitted in the uplink direction on a low bandwidth in a cellular network such as the GPRS network with an average data rate of 10 Kbit/s.
The DVB-H downlink bandwidth is approximately 500˜3000 times greater than the uplink channel which results in a large bandwidth asymmetry. Typically the maximum length of a general TCP data packet sent on the downlink channel is about 1500 bytes, and the length of an ACK packet sent on the uplink channel is 40 bytes. Since the ratio of the packet length between TCP data packet and ACK packet (1500/40=37.5) is much less than the ratio of throughput between downlink channel and uplink channel (500˜3000), this means that the high speed data downloading will cause a large number of ACK packets to be buffered in the hand held device because the data rate of the uplink channel can not satisfy the generating rate of the ACK packets.
As a result of the large bandwidth asymmetry, the blocked ACK packets increase the round trip time (RTT) of the TCP connection and degrade the transmission throughput. Furthermore, the buffered ACK packets will also occupy a lot of resources of the hand held device which will impact on the device performance and other communication processes.
The document “Shekhar et al., Performance Optimisation of TCP/IP over Asymmetric Wired and Wireless links” describes a buffer management solution called SAD (Smart Ack Dropper) for performance optimization of TCP in asymmetric networks. The basic idea of the SAD solution is to monitor the Ack queue status and maintain an Ack sequence number table at the communication node in order to suppress the number of Ack packets belonging to the same flow.
It is an aim of embodiments of the present invention to overcome at least the problems identified above.
SUMMARY OF THE INVENTION
According to a first aspect of the invention there is provided a method of transmitting data in a communication system comprising transmitting data packets from a first node to a second node on a first channel and transmitting an acknowledgement packet from the second node to the first node on a second channel in response to receiving a number of packets on the first channel, wherein the number of data packets that the acknowledgment packet is sent in response to is adjustable.
According to a second aspect of the present invention there is provided a communication system for transmitting data between a first node and a second node comprising means for transmitting data packets from a first node to a second node on a first channel and means for transmitting an acknowledgement packet from the second node to the first node on a second channel in response to receiving a number of packets on the first channel, wherein the number of data packets that the acknowledgment packet is sent in response to is adjustable.
According to a third aspect of the present invention there is provided a device for transmitting data in a communication system comprising means for receiving data packets from a network node on a first channel and means for transmitting an acknowledgement packet from to the first network node on a second channel in response to receiving a number of packets on the first channel, wherein the number of data packets that the acknowledgment packet is sent in response to is adjustable.
According to a fourth aspect of the present invention there is provided a device for transmitting data in a communication system comprising a receiver arranged to receive data packets from a network node on a first channel and a transmitter arranged to transmit an acknowledgement packet from to the first network node on a second channel in response to receiving a number of packets on the first channel, wherein the number of data packets that the acknowledgment packet is sent in response to is adjustable.
These and other advantages and features of the invention, together with the organization and manner of operation thereof, will become apparent from the following detailed description when taken in conjunction with the accompanying drawings, wherein like elements have like numerals throughout the several drawings described below.
BRIEF DESCRIPTION OF THE DRAWINGS
In the following the present invention will be described with reference to the accompanying drawings in which:
FIG. 1 is a schematic representation of a DVB-H system;
FIG. 2 is a flowchart showing the steps of an algorithm used to adjust the ACK packet generation rate in accordance with an embodiment of the present invention; and
FIG. 3 is a flowchart showing the adaptive ACK generation process according to an embodiment of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Embodiments of the invention are described in relation to a broadcast network and a cellular network. However, the present invention is not restricted thereto, but any other bandwidth asynchronous systems such as some extremely asynchronous ad-hoc networks that can also be enhanced by applying the present invention.
Reference is first made to FIG. 1 which shows a schematic representation of a DVB-H system. Data such as digital video broadcasting data is downloaded from a data server 10 to a DVB-H supported hand held device 16 via a multiplexer 12 and DVB-H transmitter 14 belonging to a broadcast network 22 . The data is sent using TCP as data packets on a downlink wireless channel to hand held device 16 .
The hand held device is arranged to send ACK packets acknowledging the received TCP packets to the server 10 . ACK packets are sent on an uplink channel of the cellular network 24 via a base station 18 and the UMTS network 20 . The hand held device 16 includes a TCP sink in a TCP module 26 . The function of the TCP sink will be described hereinafter.
The device 16 is arranged to generate one ACK for receiving every K data packets. K is defined as the ACK generation rate. The ACK is sent as a cumulative acknowledgement relating to the receipt of the K data packets. In accordance with an embodiment of the invention the TCP sink is arranged to dynamically adjust the ACK packet generation rate K in accordance with the measured throughput ratio of the downlink DVB-H and the uplink cellular channel. The TCP sink is therefore arranged to monitor the TCP data packets arriving on the downlink DVB-H channel and the ACK packets sent on the uplink cellular channel.
FIG. 2 shows the steps of an algorithm used to adjust the ACK packet generation rate in accordance with an embodiment of the present invention.
At S 1 of the algorithm the TCP sink monitors an uplink buffer in the device 16 at the wireless interface and determines the number of ACK packets stored in the buffer. When the number of ACK packets exceeds a predefined threshold the algorithm continues to S 2 .
At S 2 the TCP sink enables the ACK generation algorithm.
At S 3 the TCP sink measures the number of ACK packets N sent on the uplink channel and the number of TCP data packets M arriving on the DVB-H downlink channel in a predetermined time period T.
Based on the measurement M and N, the optimal value of the ACK generation rate K is then obtained by:
K=M/N (1)
At S 4 the ACK generation rate K is set according to equation 1.
At S 5 the TCP sink then employs a K-delayed ACK process to generate one ACK packet for every K continuously received data packets. The K-delayed ACK generation process of S 5 is shown in FIG. 3 .
Referring to FIG. 3 , at 100 the TCP sink sets the ACK packet counter to C=0.
At 200 the TCP sink receives a new data packet and determines the sequence number of the data packet, herein referred to as l_seq. The sequence number is included in the header of the data packet.
As discussed previously, the data server 10 will only continue to send data packets if it receives ACK packets from the device 16 . It has been found that the maximum delay between the transmissions of subsequent ACK packets should not exceed 500 ms in order to achieve good TCP granularity. In accordance with an embodiment of the invention the maximum delay guarantee is set at 200 ms. Accordingly, at 300 the TCP sink determines if the interval after the most recently generated ACK packet exceeds 200 ms.
If the interval after the most recently generated ACK packet does exceed 200 ms, the process continues to S 400 .
At S 400 the TCP sink immediately generates an ACK packet for the arriving data packet with the sequence number l_seq. The process then returns to 200 .
If the interval after the most recently generated ACK packet does not exceed 200 ms, the process continues to S 500 .
At S 500 the TCP sink determines if the received data packet with the sequence number l_seq is the next packet in the sequence.
If it is detected that the received packet was not the next expected packet in the sequence after a previously received packet, this indicates that there is a gap in the current data sequence and the process continues to S 400 where the TCP sink immediately generates an ACK packet for the arriving data packet with the sequence number l_seq. The process then returns to S 200 .
If it is detected that the received packet was the next expected packet in the sequence, the process continues to S 600 .
At S 600 the TCP sink detects if the received packet has the largest packet sequence number received thus far. If so this indicates that the packet is the latest in the sequence and the process continues to S 700 . If not this indicates that an earlier packet has arrived late and that there is a gap in the sequence and the process continues to S 400 where a new ACK is generated immediately.
At 700 the TCP sink checks the counter and determines if the counter is at a value K−1. If the counter is at a value K−1, this indicates that the data packet received is the Kth data packet received since the last ACK packet was sent and the process continues to S 800 .
At S 800 the TCP sink immediately generates an ACK packet for the arriving data packet with the sequence number l_seq. The process then returns to S 100 where the counter is reset to C=0.
If the counter is not yet at a value K−1, this indicates that the data packet received is not the Kth data packet received since the last ACK packet was sent and the process continues to S 900 .
At 900 the TCP sink is arranged to increase the counter by one. The process then continues to 200 .
Returning to FIG. 2 , at S 6 the TCP sink checks the receiving status to predict if a timeout may occur. This may be achieved by timing the gaps between the receipt of data packets. According to an embodiment of the invention the TCP sink estimates the RTT (Round Trip Time) of the TCP connection in order to determine a RTO (Retransmission Time Out) value prediction. For example, the RTT estimation can be done just by simply letting the TCP sink send an echo ICMP (Internet Control Message Protocol) packet to the sender and measure the time interval before receiving the echo response from the TCP server. Based on measured RTT, the RTO value can be calculated according to a TCP standard specification. Various ways of predicting the RTO value are known in the art and will therefore not be described herein. The inventors of the present invention have found that the precision of RTO prediction does not have any key influence on the algorithm performance.
If at S 6 it is detected that new data packets have been received during the RTO period the algorithm continues to S 7 .
At S 7 the TCP sink checks if there are any blocked ACK packets in the uplink buffer. If there are no ACK packets blocked in the uplink buffer for a predefined period, this indicates that the ACK packet generation frequency is too low. The algorithm then continues to S 8 .
At S 8 the ACK generation rate K is halved. The process then continues to S 5 .
If there are some ACK packets in the uplink buffer the value of K does not need to be updated until a predetermined time when the value of K is reset by re-evaluating the uplink and downlink data rates. Thus if it is determined that there are ACK packets in the buffer, the algorithm continues to S 9 where the TCP sink maintains a K-updating timer. When the predetermined time for updating the value of K expires the algorithm continues to S 3 to update the value of downlink and uplink throughput ratio dynamically for optimal performance.
If at S 6 it is determined that no data packets have been received during the RTO period the algorithm continues to S 10 .
At S 10 the TCP sink sets K to a value of one thus generating an ACK packet to acknowledge the last data packet received since the last ACK packet was sent, and thereby cumulatively acknowledging all of the remaining previously unacknowledged data packets.
The adaptive ACK generation process will be disabled until the TCP congestion window is recovered. Accordingly, after S 10 the algorithm continues to S 1 whereby the adaptive ACK generation process is only restarted if the number of ACK packets in the uplink buffer reaches the threshold described previously.
According to an alternative embodiment of the present invention the value of K may be set using equation (1) as described in S 3 and then updated regularly by repeating the measurements of M and N at predetermined time intervals.
The required data processing functions may be provided via one or more data processor entities. All required processing may be provided in the TCP module 26 of FIG. 1 . An appropriately adapted computer program code product, embodied in a computer-readable medium, may be used for implementing the embodiments, when loaded to a processor, for example for computations required when determining the value of K. The program code product for providing the operation may be stored on and provided via a carrier medium such as a carrier disc, card or tape. A possibility is to download the program code product via a data network. Implementation may be provided with appropriate software in a server.
The present invention is described in the general context of method steps, which may be implemented in one embodiment by a program product including computer-executable instructions, such as program code, executed by computers in networked environments. Generally, program modules include routines, programs, objects, components, data structures, etc. that perform particular tasks or implement particular abstract data types. Computer-executable instructions, associated data structures, and program modules represent examples of program code for executing steps of the methods disclosed herein. The particular sequence of such executable instructions or associated data structures represents examples of corresponding acts for implementing the functions described in such steps.
Software and web implementations of the present invention could be accomplished with standard programming techniques with rule based logic and other logic to accomplish the various database searching steps, correlation steps, comparison steps and decision steps. It should also be noted that the words “component” and “module,” as used herein and in the claims, is intended to encompass implementations using one or more lines of software code, and/or hardware implementations, and/or equipment for receiving manual inputs.
The Applicant draws attention to the fact that the present invention may include any feature or combination of features disclosed herein either implicitly or explicitly or any generalisation thereof, without limitation to the scope of any of the present claims. The foregoing description of embodiments of the present invention have been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the present invention to the precise form disclosed, and modifications and variations are possible in light of the above teachings or may be acquired from practice of the present invention. The embodiments were chosen and described in order to explain the principles of the present invention and its practical application to enable one skilled in the art to utilize the present invention in various embodiments and with various modifications as are suited to the particular use contemplated. | A method of transmitting data in a communication system. Data packets are transmitted from a first node to a second node on a first channel. An acknowledgement packet is transmitted from the second node to the first node on a second channel in response to receiving a number of packets on the first channel. The number of data packets that the acknowledgment packet is sent in response to is adjustable. | 7 |
CROSS REFERENCE TO RELATED APPLICATIONS
This application claims the benefit of U.S. Provisional Application Ser. Nos. 60/035,958, filed on Jan. 21, 1997; and 60/038,066, filed on Feb. 18, 1997.
INTRODUCTION
The present invention is directed to fabric weaving devices, and, more particularly, to fabric weaving devices and methods for producing fabrics having predetermined air permeability.
BACKGROUND OF THE INVENTION
Conventional weaving reeds, rotors and functional equivalents having fixed dent spacing produce finished fabrics with variable warp end density across the entire width of the fabric excluding any possible special selvedge. Most fabrics have different variations in warp end density across the width of finished fabrics due to different yarns and processes. In the case of air bag fabrics, there may be less or more warp end density towards the fabric's edge. In the case of lesser density toward the fabric edge, this is caused by the weaving and finishing processes in which the fabric's edges will be stretched out more than the middle part of the fabric due to tension and heat. As a result of these factors, the density of the finished fabric varies across its width and, consequently, the center of the fabric is more dense. This difference in density can be viewed by studying the finished fabric. Such a finished fabric has a density curve, that is, warp end density as measured in ends/inch, with an inverted U shape as depicted in FIG. 2, where a greater density exists at the center of the finished fabric. The actual warp end density varies across the width of the fabric from the left (L), through the left center (LC), center (C), right center (RC), and to the right (R) portions of the fabric. Some fabrics, in particular, certain of those produced for paper making processes, are subject to different processing conditions which result in a density curve opposite to that of the typical fabric previously discussed. Typically, the edges of these finished paper making fabrics are more dense than the middle.
This variation in warp end density across the entire width of a fabric will affect the mechanical properties of the fabric, especially the air permeability. Air permeability is a function of fabric density (i.e. the denser the fabric, the lesser the air permeability). The fabric density is controlled by warp end density and filling yarn (weft yarn) density for chosen yarns, weave, loom, finishing processes and other weaving conditions. For instance, a typical air bag fabric produced with a conventional reed, which is either plain or profiled, may produce a fabric with a warp end density variation across the width of the fabric as depicted in FIG. 2 . There is virtually no filling yarn density variation under normal conditions. Therefore, the density variation across the width of a given fabric is caused by the variation of warp end density.
A typical prior art reed 2 is shown in FIGS. 1, 1 A, where a plurality of reed wires 4 are connected at their ends to a top baulk 6 and a bottom baulk 8 . The reed wires 4 are separated by spaces 10 . A dent 12 comprises a wire 4 and an adjacent space 10 . A conventional reed wire 4 is shown in FIG. 1B, while a profile reed wire 4 ′ is shown in FIG. 1 C.
Air permeability is a critical property of some industrial fabrics such as air bag and filtration fabrics. In the case of air bag fabrics, manufacturers have used many methods to control air permeability including the use of calendering, coatings, impregnation, special weave designs, special air bag constructions, envelopes and layers of differing air permeability, and other methods. These methods may result in: increased costs, limited recyclability in the case of coatings, increased waste, and complicated constructions. The venting of air bags through the fabric may not be possible due to variation in air permeability of the fabric and the resulting unpredictable mode of operation. An example of an air bag with vent holes is shown in U.S. Pat. No. 5,566,972 to Yoshida et al. Examples of air bags using several fabric sections with differing air permeability are seen in U.S. Pat. No. 5,375,878 to N. Ellerbrook, and U.S. Pat. No. 5,566,434 to A. W. Beasley. Another method for making air bag fabric is to utilize special yarns to weave a fabric of low air permeability obviating the need for coating or other processes, as seen in U.S. Pat. No. 5,474,836 to Nishimura et al., and U.S. Pat. No. 5,508,073 to Krummheuer et al. The present invention can improve such a fabric by providing virtually no variation of air permeability across the width of the fabric and may possibly reduce fabric waste in the process of making an air bag. The present invention can also offer an air bag fabric of variable density, which, after construction into an air bag, could result in more uniform air permeability at maximum deployment.
A non-uniform product may result, such as in the case of paper making fabrics, from variations in the fabric. Examples of paper making fabric are shown in U.S. Pat. No. 4,649,964 to R. W. Smith and U.S. Pat. No. 4,588,632 to Gisbourne et al. The present invention can provide a uniform fabric.
A fabric having a differential density is depicted in U.S. Pat. No. 4,698,276 to Duval et al., which is an example of a decorative fabric used to produce drapery. The present invention can produce a fabric which may be suitable for this usage while obviating the need for a complicated construction provided by the assemblage of strips of fabric with various fabric densities. Further, a fabric of variable densities may be suitable for an air bag fabric whereby these densities, when predetermined, could produce a controlled deflation of the air bag by, for example, utilizing a greater density where the fabric stretches more and a lesser density where the fabric stretches less to produce, in effect, less or possibly no variation in air permeability.
Reed type devices which do not perform strenuous beat-up functions are shown, for example, in U.S. Pat. No. 5,368,076 to F. H. Curzio. This reed is actually a warp guiding device but is designed to affect warp end density in net type, loosely woven type fabrics. These fabrics are intended to act as reinforced fabric for composite materials to cover three dimensional mandrels. This reed is of a different design peculiar to making net fabrics where consistent air permeability is not a factor. The reed is shaped to make fabrics for a three dimensional mandrel. Further, this reed design could not perform the functions of the present invention.
Other reed designs include reeds with adjustable or removable dents such as those depicted in U.S. Pat. No. 5,029,617 to Anderson et al. The reed of Anderson cannot correct the warp end density variation as can the present invention because of the spaced relationship of the dents. Regardless of how closely spaced the dents are made in the removable dent reed it could not offer the control of warp end variation available in the present invention. Each adjacent reed wire and removal of same in this removable dent reed would preclude providing the desired spacing needed to produce the fabrics thereby produced by the present invention. Reeds with adjustable or removable dents are utilized generally to insert a larger warp yarn, perhaps to effect a change in the appearance of a decorative fabric, provide a certain selvedge, or provide reinforcement in an industrial fabric. Further, these reeds are also employed to ease maintenance, as a damaged wire can be readily replaced. The adjustable reed may, for instance, be used to produce net shaped fabrics in a variety of shapes, as seen in U.S. Pat. No. 5,465,762 to G. L. Farley. Another type of reed is depicted in U.S. Pat. No. 5,158,116 to Kazuo et al., whereby the dent spacing varies to accommodate thick yarns to facilitate the weaving process.
BRIEF SUMMARY OF THE INVENTION
The present invention relates to weaving devices having weaving elements such as reeds, discs, and lamellae or similar functioning elements. These devices may include conventional reeds, rotary reeds, and weaving rotors such as those used on multiple shed looms. More particularly, the present invention relates to a weaving reed with a construction such that warp end density variation is controlled, or the warp end density can be changed, across the entire width of a fabric. Furthermore, the present invention will affect the mechanical properties of the fabric. One embodiment of this invention and a quality of such a fabric thereby produced includes virtually no variation of air permeability across the entire width of the finished fabric. Alternatively, other embodiments of this invention may produce changes in warp end density of a given fabric depending on reed dent spacing or dent group spacings chosen for a desired effect. The present invention, utilizing a reed of variably spaced dents, will be of use in any application requiring a fabric with virtually no variation, or to produce a desired predetermined change, in warp end density. A fabric produced by the present invention with this reed is suitable, in particular, for an uncoated air bag fabric. The present invention can also offer a new fabric which is comprised of different warp end densities in selected areas of the fabric which can alternatively be of service to, for example, air bag fabric assemblies.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic plan view of a conventional reed of the of prior art with fixed dent spacings.
FIG. 1A is a schematic enlarged plan view of a portion of the reed wires and spaces of the reed of FIG. 1 .
FIG. 1B is a schematic side elevation view of a plain reed wire of the reed of FIG. 1 .
FIG. 1C is a schematic side elevation view of a profile reed wire of the reed of FIG. 1 .
FIG. 2 is a schematic graphical representation of the warp end density variation across the width of a typical prior art woven air bag fabric.
FIG. 3 is a schematic graphical representation of the air permeability across the width of the prior art woven air bag fabric of FIG. 2 .
FIG. 4 is a schematic graphical representation of the dent spacing measured by reed gauge across a reed according to the present invention.
FIG. 5 is a schematic graphical representation of the air permeability across the width of a fabric woven using the reed having the dent spacing of FIG. 4 .
FIG. 6 is a schematic plan view of one embodiment of a reed according to the present invention.
FIG. 6A is a schematic enlarged plan view of a portion of the reed wires and spaces of the reed of FIG. 6 .
FIG. 7 is a schematic plan view of another embodiment of a reed according to the present invention.
FIG. 7A is a schematic enlarged plan view of a portion of the reed wires and spaces of the reed of FIG. 7 .
FIG. 8 is a schematic plan view of another embodiment of a reed according to the present invention.
FIG. 8A is a schematic enlarged plan view of a portion of the reed wires and spaces of the reed of FIG. 8 .
FIG. 9 is a schematic graphical representation of another embodiment of a reed according to the present invention showing the spacing of dent groups along the length of the reed as depicted in FIG. 4 .
FIG. 10 is a schematic graphical representation of another embodiment of a reed according to the present invention showing the spacing of dent groups along the length of the reed as depicted in FIG. 4 .
FIG. 11 is a schematic graphical representation of dent spacing for a reed according to one embodiment of the present invention which produces a non-uniform air permeability across the width of a fabric.
FIG. 12 is a schematic graphical representation of the air permeability across the width of a fabric using the dent spacing of FIG. 11 .
FIG. 13 is a schematic graphical representation of dent spacing for a reed according to another embodiment of the present invention which produces a non-uniform air permeability across the width of a fabric.
FIG. 14 is a schematic graphical representation of the air permeability across the width of a fabric using the dent spacing of FIG. 13 .
FIG. 15 is a schematic graphical representation of dent spacing for a reed according to another embodiment of the present invention which produces a non-uniform air permeability across the width of a fabric.
FIG. 16 is a schematic graphical representation of the air permeability across the width of a fabric using the dent spacing of FIG. 15 .
FIG. 17 is a schematic graphical representation of dent spacing for a reed according to another embodiment of the present invention which produces a non-uniform air permeability across the width of a fabric.
FIG. 18 is a schematic graphical representation of the air permeability across the width of a fabric using the dent spacing of FIG. 17 .
FIG. 19 is a schematic perspective view of another embodiment of the present invention having a rotary type reed.
FIG. 20 is a schematic representation of the embodiment of FIG. 19 .
FIG. 21 is a schematic plan view of another embodiment of the present invention having a weaving rotor.
FIG. 22 is a schematic front elevation view of the weaving rotor of FIG. 21 .
FIG. 23 is a schematic side elevation view of the weaving rotor of FIG. 21 .
DETAILED DESCRIPTION OF THE INVENTION
Accordingly, one embodiment of the present invention is to provide a weaving reed which can produce improved fabrics by controlling the variation of warp end density across the entire width of the finished fabric. However, a thorough study of the variation of warp end density across the width of the finished fabric produced by a conventional fixed dent reed of the prior art (see FIGS. 1-1C, 2 , 3 ), is vital to the successful implementation of this invention in a given fabric.
FIGS. 2 and 3 depict a typical prior art woven fabric, for example, an air bag fabric of 630 denier high-tenacity nylon yarn with a nominal density of 41×41 ends/inch. The actual warp end density across the width of the prior art fabric is shown by the curve depicted in FIG. 2 . In this example the warp end density of the fabric is about 42.7 ends/inch at the middle of the fabric while only about 37.5 ends/inch at the edges of the fabric. This warp end density will give this fabric the air permeability variation across the width of the fabric following the curve depicted in FIG. 3, showing the air-permeability at the middle of the fabric to be about 2.5 cfm (at 124 Pascals) while it is about 4 cfm (at 124 Pascals) towards the edges.
One preferred embodiment of this invention, while not limited to any particular beat-up type reed construction or gauge (also called pitch or count and measured in dents/inch), is a plain reed, or a reed having any profile or functional equivalents, for use on virtually any type of loom, which is comprised of reed elements having variable dent spacing where required, that can be accomplished by the following example constructions. The present invention can have reed elements such as fixed wires and variable spaces between the wires to achieve variably spaced dents, as seen in FIGS. 6, 6 A. Alternatively, the present invention can have fixed spaces between wires and variable wire thicknesses to achieve variably spaced dents, as seen in FIGS. 7, 7 A. Yet alternatively, the present invention may have a combination of variable spaces between wires and variable wire thicknesses to achieve variably spaced dents, as seen in FIGS. 8, 8 A. Functional equivalents such as rotary reeds and weaving rotors may have related parts that require adjustment to achieve the new spacings provided by the constructions described in this disclosure. The aforementioned constructions of the present invention, in certain preferred embodiments, produce a finished fabric with virtually consistent warp end density across the width of the fabric. In effect the variation of warp end density across the width of the finished fabric is adjusted for during weaving by the present invention.
To correct the variation of warp end density across the width of the prior art fabric shown in FIG. 2, the present invention is designed with variable dent spacing along the entire length of the reed. The reed gauge in dents per inch is depicted graphically in FIG. 4 . The reed gauge at both ends of the reed is about 42.5 dents/inch based on a dent spacing (which is the thickness of one wire plus the width of one adjacent space) of about 0.0235 inches. The middle of the reed has a dent spacing of about 0.0282 inch, producing a reed gauge of about 35.5 dents/inch. Such a reed will produce a fabric with consistent warp end density which will give this fabric a uniform air permeability across the width of the fabric following the curve depicted in FIG. 5 . Possible constructions to achieve this variable dent spacing are depicted in FIGS. 6-8.
FIG. 6A is an enlarged view showing the first 8 dents from the left selvedge of the reed 2 of FIG. 6 . The embodiment shown in FIGS. 6, 6 A shows variable dent spacings which are achieved by having wires 4 of fixed thickness (for this example wires 4 have a thickness of 0.0100 inch), and spaces 10 of a variable width. The space 10 in first dent 26 is 0.0135 inches wide which will provide a total dent spacing for dent 26 of 0.0235 inch. The space 10 between adjacent wires 4 is increased by 0.0001 inch increments progressively along reed 2 to a maximum amount at a desired point, from which spaces 10 begin to decrease by the same amount, which is illustrated more clearly in the graph of FIG. 4 showing the reed gauge resulting from this dent spacing. Space 10 between wires 4 at the eighth dent 27 is 0.0142 inch which will give a total dent spacing for eighth dent 27 of 0.0242 inch.
Another embodiment is depicted in FIGS. 7, 7 A, where a reed 2 of the present invention is shown with variable dent spacings achieved by having fixed spaces 10 (0.0135 inch in this example) between adjacent wires 4 which have varying wire thicknesses. In the illustrated embodiment, the thickness of wire 4 in the first dent 28 is about 0.0100 inch. This will give a total dent spacing for first dent 28 of 0.0235 inch. Similarly to FIGS. 6, 6 A, the thickness of wires 4 is increased by 0.0001 inch increments progressively along reed 2 to a maximum thickness at a desired point from which the thickness begins to decrease at the same rate. The actual wire thickness at the eighth dent 29 is 0.0107 inch which will give a total dent spacing for eighth dent 29 of 0.0242 inch.
FIGS. 8, 8 A depict another embodiment of a reed of the present invention with variable dent spacings achieved by combining variable wire 4 thicknesses and variable space 10 widths. The construction dimensions of the first eight dents are as follows: First dent 30 has a wire 4 thickness of 0.0103 inch, and a space 10 width of 0.0132 inch, for a total dent spacing for first dent 30 of 0.0235 inch. Second dent 31 has a wire 4 thickness of 0.0100 inch and a space 10 width of 0.0136 inch, for a total dent spacing for second dent 31 of 0.0236 inch. Third dent 32 has a wire 4 thickness of 0.0100 inch and a space 10 width of 0.0137 inch, for a total dent spacing for third dent 32 of 0.0237 inch. Fourth dent 33 has a wire 4 thickness of 0.0104 inch and a space 10 width of 0.0134 inch, for a total dent spacing for fourth dent 33 of 0.0238 inch. Fifth dent 34 has a wire 4 thickness of 0.0105 inch and a space 10 width of 0.0134 inch, for a total dent spacing for fifth dent 34 of 0.0239 inch. Sixth dent 35 has a wire 4 thickness of 0.0106 inch and a space 10 width of 0.0134 inch, for a total dent spacing for sixth dent 35 of 0.0240 inch. Seventh dent 36 has a wire 4 thickness of 0.0104 inch and a space 10 width of 0.0137 inch, for a total dent spacing for seventh dent 36 of 0.0241 inch. Eighth dent 37 has a wire 4 thickness of 0.0107 inch and a space 10 width of 0.0135 inch, for a total dent spacing for eighth dent 37 of 0.0242 inch. The aforementioned dimensions are shown purely for illustrating the workings of the present invention and must be adjusted according to the desired result in a given fabric. The aforementioned example reed dent dimensions almost perfectly correct the curve depicted in FIG. 2 .
The present invention can be simplified as depicted in FIG. 9, which graphically represents the reed gauge in dents/inch across the width of a fabric of a reed of another preferred embodiment of the present invention having dent groups. In this embodiment, the entire length of the reed is divided into 27 groups of dents, i.e. a wire 4 and a space 10 , where the dent spacing of each dent in a group is the same but different from the spacing of the dents of at least its adjacent groups. While the result will not be as perfect as what may be achieved with the reeds depicted in the embodiments of FIGS. 6, 6 A, 7 , 7 A, or 8 , 8 A, it will serve well for most practical purposes. The specific dent spacings of the groups of this embodiment are as follows: dent group 40 is 0.0240 inch, dent group 41 is 0.0242 inch, dent group 42 is 0.0245 inch, dent group 43 is 0.0248 inch, dent group 44 is 0.0252 inch, dent group 45 is 0.0255 inch, dent group 46 is 0.0258 inch, dent group 47 is 0.0261 inch, dent group 48 is 0.0265 inch, dent group 49 is 0.0268 inch, dent group 50 is 0.0272 inch, dent group 51 is 0.0276 inch, dent group 52 is 0.0280 inch, dent group 53 is 0.0276 inch, dent group 54 is 0.0272 inch, dent group 55 is 0.0268 inch, dent group 56 is 0.0265 inch, dent group 57 is 0.0261 inch, dent group 58 is 0.0258 inch, dent group 59 is 0.0255 inch, dent group 60 is 0.252 inch, dent group 61 is 0.0248 inch, dent group 62 is 0.0245 inch, dent group 63 is 0.0242 inch, dent group 64 is 0.240 inch, dent group 65 is 0.0237 inch, and dent group 66 is 0.0234 inch.
The present invention can be simplified yet further with other groupings of dents as depicted in the embodiment of FIG. 10 . In this embodiment the entire length of the reed is divided into 14 groups of dents. In a manner similar to the embodiment of FIG. 9, the spacing of the dents within each group is the same, but the spacing of each group is different from at least its adjacent groups: Dent group 70 is 0.0240 inch, dent group 71 is 0.0245 inch, dent group 72 is 0.0252 inch, dent group 73 is 0.0258 inch, dent group 74 is 0.0265 inch, dent group 75 is 0.0272 inch, dent group 76 is 0.0280 inch, dent group 77 is 0.0272 inch, dent group 78 is 0.0265 inch, dent group 79 is 0.0258 inch, dent group 80 is 0.0252 inch, dent group 81 is 0.0245 inch, dent group 82 is 0.0240 inch, and dent group 83 is 0.0234 inch.
Both of the simplified reeds depicted in FIGS. 9, 10 can be designed by varying the weaving element thickness, that is, the reed wire, rotary reed disc, or lamellae in a weaving rotor thickness, or varying space widths or a combination of these two. Such variable wire thicknesses and spacing widths need not necessarily be variable entirely across the length of the reed in order to provide a certain amount of warp end density variation correction. Rotary reeds and weaving rotors may have related parts used in conjunction with same which must be adjusted to match new spacings provided by the constructions described in this disclosure. To correct greater variation in warp end density of the finished fabric one may use smaller groupings of dents (i.e. fewer dents per group). To correct smaller variations in the warp end density of the finished fabric one may use larger groupings (i.e. more dents per group). Ideally, groupings of dents are adjusted such that the warp end density curve is matched closely enough for practical usage of the finished fabric. Matching the warp end density curve precisely is not necessary for most applications as a rough match to the curve will provide adequate correction.
As a rule, the simpler the design (fewer number of groupings), the less able the present invention will be able to correct the variation of warp end density across the width of the finished fabric. Therefore a thorough understanding of the actual variation of warp end density of any finished fabric and its end use application will determine the complexity of the present invention.
The present invention can also produce a fabric having a non-uniform air permeability. Another embodiment of the present invention is depicted in FIG. 11, which shows the reed gauge distribution for a reed which produces a fabric having a non-uniform air permeability distribution as shown in FIG. 12 . As can be seen, the distribution for this embodiment comprises three segments of uniform air permeability, with transition segments of non-uniform air permeability between adjacent segments. The two segments at the outer edges, that is, the left and right portions, of the fabric have an air permeability lower than the third segment, that is, the central portion, and substantially equal to one another. The central portion, of the fabric has a constant air permeability which is higher than the two segments at the outer edges. There are two transition segments, each having a sloped distribution of air permeability between an outer segment and the center portion segment.
The embodiment depicted in FIG. 13 shows the reed gauge distribution for a reed which produces a fabric having a non-uniform air permeability distribution as shown in FIG. 14 . As can be seen, this distribution comprises three major segments having curved, or substantially shallow U-shaped, distributions with sharp transitions, or breaks, between each segment. The outer segments have a generally lower air permeability than the central segment, with the lowest air permeability being at the center of the segments and the greatest air permeability at the outer edges of the segments. The central segment as well as its lowest air permeability at its center and its greatest air permeability at its outer edges.
The embodiment depicted in FIG. 15 shows the reed gauge distribution for a reed which produces a fabric having a non-uniform air permeability distribution as shown in FIG. 16 . The air permeability of this embodiment follows a step curve, with alternating segments of higher then lower air permeability.
The embodiment depicted in FIG. 17 shows the reed gauge distribution for a reed which produces a fabric having a non-uniform air permeability distribution as shown in FIG. 18 . The air permeability of this embodiment follows a sinuous curve, where the distribution of air permeability undulates from higher to lower to higher air permeability.
The specific dent spacings required for the embodiments of FIGS. 11-18 are not shown here as it would be impractical due to the number required. However, sufficient detail is shown here, in combination with the discussion above with respect to the reeds which produce a uniform air permeability, to enable one skilled in the art to construct reeds having these characteristics. The curves depicted in these graphs were derived from the curve shown in FIG. 3 . The dimensions utilized for these variable spaced reeds and their effect on the air permeability across the width of the fabric are shown purely for illustrating the workings of the present invention and must be adjusted according to the desired result in a given fabric.
Disc thickness and the space between two discs on a rotary reed and lamellae thicknesses of weaving rotors and related parts for multiple-shed weaving machines can be designed according to the teachings provided herein to produce fabrics with uniform warp end density—or for a desired effect, across the width of a finished fabric.
Another embodiment of the present invention having a rotary reed is shown in perspective view in FIG. 19 and in plan view in FIG. 20 . Reed 2 ′ has stationary reed wires 4 ″ separated by spaces 10 and a rotary reed 14 . Rotary reed 14 comprises shaft 16 supporting discs 18 which are separated by spaces 10 ′. Dents 12 are formed of a reed wire 4 ″ and a space 10 , while dents 12 ′ are formed of a disc 18 and a space 10 ′. Reed 2 ′ could, when modified in a similar manner described herein form a fabric having a desired warp end density. In a manner similar to that described above with respect to FIGS. 6-8, the dent spacing can be made non-uniform by varying the thickness of reed wires 4 ″ and discs 18 , the width of spaces 10 , 10 ′, or a combination of the two. A detailed example is not needed herein as the examples illustrated above with respect to FIGS. 6-8 are sufficient to demonstrate the principle with respect to this embodiment.
Another embodiment of the present invention having a weaving rotor is shown in FIGS. 21-23. Weaving rotor 19 has a plurality of lameliae 22 separated by spaces 10 and supported on rotor 23 . Dents 12 ″ are formed of a lamella 22 and a space 10 . Warp ends 24 , and filling yarn (weft yarn) 25 , as seen in FIG. 23, run through lamellae 22 . In a manner similar to that described above with respect to FIGS. 6-8, the dent spacing can be made non-uniform by varying the thickness of lamellae 22 , the width of spaces 10 or a combination of the two. A detailed example is not needed herein as the examples illustrated with respect to FIGS. 6-8 are sufficient to demonstrate the principle with respect to this embodiment.
It is an established practice in the art of weaving to draw different number of warp ends through a dent. For example, one end per dent, two ends per dent, three ends per dent, etc. Another practice is to skip every other dent, e.g. skip one dent in two, skip one dent in three, two dents in three, two dents in four, etc. Therefore, this practice, when applied to the present invention, will produce a uniform fabric, although warp end density will be different in accordance with how many warp ends are inserted through each of the dents. Regardless of this practice, it is still possible with the present invention to produce a uniform air permeability over a given area due to the uniformity of the finished fabric. The present invention with the reeds illustrated herein, or a rotary reed and its related parts, or a weaving rotor and its related parts for multiple shed looms, utilizing the principles of these constructions, with spacings and/or wire (or disc or lamellae) thicknesses appropriate for the given yarn and conditions, can be utilized to accommodate for this practice.
Any change in yarns, weaves, weaving conditions, finishing processes and conditions will affect the warp end density distribution across the entire width of the finished fabric. Therefore, any such change requires a thorough study on the warp end density distribution across the entire width of the finished fabric. The result of this study is required to design the appropriate variably spaced dent(s) reed by using variable wire (or disc and related parts as in the case of a rotary reed or lamellae and related parts for a weaving rotor) thickness and/or variable space between wires (or discs or lamellae, and related parts), to adjust for the change. Rotary reeds and weaving rotors may have related parts used in conjunction with the same which must be adjusted to match new spacings provided by the constructions described in this disclosure.
Clearly, many permutations of the present invention are made possible in the review 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. It is understood herein that the term wire used to describe the member used in conjunction with a space to comprise a dent, may be member(s) of other material or materials. These wires, if of sufficient strength to endure beat-up without support on both the top and bottom, may preclude the need for either a top or bottom baulk. Rotary reeds and weaving rotors may have related parts used in conjunction with same which must be adjusted to match new spacings provided by the constructions described in this disclosure. | A weaving reed spacing arrangement having a plurality of reed dents fixed in certain positions and which may be located in a reed baulk. The reeds may be plain reeds or reeds, with any profile, usable virtually on any loom. The dents are formed of wires and spaces and are variably spaced. The variable spaces are formed a number of techniques to produce fabrics with a desired warp density across the entire width of a given fabric. The reed may produce a consistent warp end density which improves the mechanical properties of a given fabric and also provides virtually consistent air permeability across the width of the finished fabrics. The reed can also produce changes in warp end density in a given fabric for certain desired effects. A rotary type reed and weaving rotor for multiple-shed looms are also disclosed. | 3 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is entitled to the benefit of and incorporates by reference subject matter disclosed in the International Patent Application No. PCT/CN2013/088503 filed on Dec. 4, 2013 and Chinese Patent Application 201210535175.3 filed Dec. 10, 2012.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a plate heat exchanger.
[0004] 2. Description of the Related Art
[0005] For a paralleled-channel heat exchanger (evaporator), especially, for a plate heat exchanger and a micro channel heat exchanger, mal-distribution of the refrigerant is a worldwide technical problem. Generally, the refrigerant entered into the heat exchanger is in a two-phase manner, since complicated application conditions and two-phase flows, it is hard to achieve uniform distribution of the refrigerant. In most cases, excess liquid refrigerant will flow into some of the channels while excess gaseous refrigerant will flow into some other of the channels, which may greatly impact integral performance of the evaporator.
[0006] The prior art solution for refrigerant distribution is achieved based on a distributor technology. There are common measures liking guide duct, guide ring, embedded distributor, etc. The main concept of the prior art solution is to dispose an inlet of each channel of the heat exchanger to have a small circulation cross section, such as a small hole and small slit, to control mass flow rate of the refrigerant into the channel, so as to uniform overall refrigerant distribution. Since aperture size of the distributor is generally about 0.5-2.0 mm, the technology faces great challenges in design and manufacturing.
SUMMARY
[0007] The present invention has been made to overcome or alleviate at least one aspect of the above mentioned disadvantages existing in the conventional technical solutions.
[0008] Accordingly, it is an object of the present invention to provide a plate heat exchanger, which, for example, may achieve uniform distribution of the refrigerant while being independent of the distributors.
[0009] According to one aspect of the present invention, there is provided a plate heat exchanger comprising:
[0010] heat exchange plates each forms one or more first fluid channels and one or more second fluid channels,
[0011] wherein a first fluid flows in the one or more first fluid channels, while a second fluid flows in the one or more second fluid channels, and
[0012] wherein the one or more first fluid channels each has a fluid channel upstream portion and a fluid channel downstream portion separated from the fluid channel upstream portion, wherein the fluid channel upstream portion is fluidly communicated via a fluid communication device with the fluid channel downstream portion.
[0013] According to one aspect of the present invention, the plate heat exchanger further comprises an outlet of the fluid channel upstream portion and an inlet of the fluid channel downstream portion, the outlet of the fluid channel upstream portion is fluidly communicated via the fluid communication device with the inlet of the fluid channel downstream portion.
[0014] According to one aspect of the present invention, the plate heat exchanger further comprises a divider which separates the fluid channel upstream portion from the fluid channel downstream portion.
[0015] According to one aspect of the present invention, the plate heat exchanger further comprises an outlet of the fluid channel upstream portion and an inlet of the fluid channel downstream portion, the outlet of the fluid channel upstream portion and the inlet of the fluid channel downstream portion are adjacent to the divider.
[0016] According to one aspect of the present invention, the fluid communication device comprises a channel or a chamber.
[0017] According to one aspect of the present invention, the plate heat exchanger further comprises: an end plate provided on an outer side of the heat exchange plate and having a recess which, together with a corresponding portion of the outer side of the heat exchange plate, forms a chamber as the fluid communication device; the outlet of the fluid channel upstream portion and the inlet of the fluid channel downstream portion are fluidly communicated with the chamber.
[0018] According to one aspect of the present invention, the plate heat exchanger further comprises: an end plate provided on an outer side of the heat exchange plate; and a chamber plate disposed on the outer side of the end plate and having a recess which, together with a corresponding portion of the outer side of the end plate, forms a chamber as the fluid communication device; the outlet of the fluid channel upstream portion and the inlet of the fluid channel downstream portion are fluidly communicated with the chamber.
[0019] According to one aspect of the present invention, the recess is adjacent to a separation between the fluid channel upstream portion and the fluid channel downstream portion.
[0020] According to one aspect of the present invention, the heat exchange plate is an integral heat exchange plate.
[0021] According to one aspect of the present invention, a distance between the divider and the inlet of the first fluid channels is about 50-80% of the length of the heat exchange plate.
[0022] According to one aspect of the present invention, the divider is at least one of line-shaped brazed or soldered joint and metal plate.
[0023] According to one aspect of the present invention, the fluid communication device comprises a fluid mixing chamber.
[0024] According to one aspect of the present invention, the one or more first fluid channels and the one or more second fluid channels are alternately disposed in a laminated direction of the heat exchange plates.
[0025] According to one aspect of the present invention, flow resistance of the fluid channel upstream portion is greater than that of the fluid channel downstream portion, or, flow resistance per unit length of the fluid channel upstream portion is greater than that of the fluid channel downstream portion.
[0026] According to one aspect of the present invention, the outlet of the fluid channel upstream portion constitutes an upstream port chamber, the inlet of the fluid channel downstream portion constitutes a downstream port chamber, and, the upstream port chamber and the downstream port chamber are directly communicated or connected with the fluid communication device.
[0027] The plate heat exchanger according to the embodiment of the present invention achieves distribution of the refrigerant while being independent of the distributors, and, optimizes effectively distribution of the refrigerant and heat transfer operation on the heat exchange plate, by means of corresponding reinforced heat transfer measures.
[0028] As apparent from the above, the plate heat exchanger according to the embodiment of the present invention at least has following advantages:
[0029] 1. uniform distribution of the refrigerant being independent of the distributors;
[0030] 2. provision of different heat exchange regions in the channels on the basis of heat-transfer mechanism correlated to refrigerant evaporation, to reinforce the heat transfer;
[0031] 3. reduction of difficulties on productions and manufacturing and widening of practical application scopes and conditions, by means of the heat exchanger without the distributors;
[0032] 4. more spaces for type selection of the expansion valve, as there is no distributor in the plate heat exchanger, and compared with other similar products, the refrigerant flow path has a lower total pressure drop; and
[0033] 5. realization of reinforcing the heat transfer during the condensation process of the refrigerant, for the cases where the evaporator works as the condenser (in a reverse operation of the system).
BRIEF DESCRIPTION OF THE DRAWINGS
[0034] These and/or other aspects and advantages of the invention will become apparent and more readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:
[0035] FIG. 1 is a schematic view of a plate heat exchanger according to a first embodiment of the present invention;
[0036] FIG. 2 is a schematic view of an end plate of the plate heat exchanger according to the first embodiment of the present invention;
[0037] FIG. 3 is a schematic view of another end plate of the plate heat exchanger according to the first embodiment of the present invention;
[0038] FIG. 4 a is a schematically front view of a chamber plate of the plate heat exchanger according to the first embodiment of the present invention, FIG. 4 b is a schematically sectional view taken along line A-A in FIG. 4 a , and, FIG. 4 c is a schematically sectional view taken along line B-B in FIG. 4 a;
[0039] FIG. 5 is a schematically perspective view of the chamber plate of the plate heat exchanger according to the first embodiment of the present invention;
[0040] FIG. 6 a is a schematically front view of the plate heat exchanger according to the first embodiment of the present invention;
[0041] FIG. 6 b is a schematically sectional view taken along line A-A in FIG. 6 a;
[0042] FIG. 7 is a schematic perspective view of the plate heat exchanger according to the first embodiment of the present invention;
[0043] FIG. 8 is a schematic view showing a fluid flow path in one first fluid channel of the plate heat exchanger according to the first embodiment of the present invention;
[0044] FIG. 9 is a schematic view of a heat exchange plate of a plate heat exchanger according to a second embodiment of the present invention;
[0045] FIG. 10 is a schematic view of another heat exchange plate of the plate heat exchanger according to the second embodiment of the present invention;
[0046] FIG. 11 is a schematic view of flowing of fluids in a dual circuit plate heat exchanger according to a third embodiment of the present invention; and
[0047] FIG. 12 is a schematic view of a heat exchange plate of the dual circuit plate heat exchanger according to the third embodiment of the present invention.
[0048] The scope of the present invention will in no way be limited to the simply schematic views of the drawings, the number of constituting components, the materials thereof, the shapes thereof, the relative arrangement thereof, etc., are disclosed simply as an example of an embodiment.
DETAILED DESCRIPTION
[0049] Exemplary embodiments of the present disclosure will be described hereinafter in detail with reference to the attached drawings, wherein the like reference numerals refer to the like elements. The present disclosure may, however, be embodied in many different forms and should not be construed as being limited to the embodiment set forth herein; rather, these embodiments are provided so that the present disclosure will be thorough and complete, and will fully convey the concept of the disclosure to those skilled in the art.
[0050] It will be appreciated that the orientation in the drawings does not denote practical use orientation for the plate heat exchanger. And, the drawings are only for demonstration purposes.
1 st Embodiment
[0051] Referring to FIGS. 1-8 , the plate heat exchanger 100 according to the embodiment of the present invention comprises heat exchange plates 10 each forms one or more first fluid channels 12 and one or more second fluid channels and end plates 11 and 13 . The ends plates 11 and 13 are provided on the outer side of the plate heat plate 10 .
[0052] As shown in FIGS. 2 and 3 , each of the ends plates 11 and 13 has the same through holes as the corresponding side surface of the heat exchange plate 10 . The heat exchange plate 10 may be integral. The plate heat exchanger 100 further comprises a first fluid inlet 1 , a first fluid outlet 7 , a second fluid outlet 2 (for a reverse-flow evaporator) and a second fluid inlet 6 (for a reverse-flow evaporator). First fluid, such as refrigerant, flows in one first fluid channel 12 , and, second fluid, such as water, flows in one second fluid channel. Aperture size of the first fluid inlet 1 may be less than that of the first fluid outlet 7 .
[0053] These heat exchange plates 10 are laminated one by one to form alternately the first fluid channels 12 and the second fluid channels in the lamination direction. For example, the heat exchange plates 10 shown in FIG. 1 are laminated alternately with heat exchange plates 10 that are in a mirror symmetry relationship to the one shown in FIG. 1 , or, with heat exchange plates 10 of another kind. That is, the first fluid channel, which is formed by mating of the heat exchange plate 10 shown in FIG. 1 to a heat exchange plate 10 of another kind, is separated into two regions, while, the second fluid channel is in a direct communication manner and owns seal effect at portions of the second fluid channel corresponding to outlet 3 of an upstream portion 12 U and inlet 5 of a downstream portion 12 D such that the second fluid is not in direct contact with the first fluid. Apparently, those skilled in the art may achieve the second fluid channel by various means, while the first fluid channel 12 may be formed by the heat exchange plates 10 shown in FIG. 1 .
[0054] As shown in FIGS. 1 and 6 a - 8 , the first fluid channel 12 has the fluid channel upstream portion 12 U and the fluid channel downstream portion 12 D which are separated from each other in a flow direction of the fluid by means of a divider 4 . The fluid channel upstream portion 12 U is fluidly communicated via a fluid communication device 15 with said fluid channel downstream portion 12 D. For example, at the middle of the first fluid channel 12 , in a length direction of the heat exchange plate 10 or substantially in a flow direction of the fluid (for example, the refrigerant) in the first fluid channel 12 , the first fluid channel 12 is separated into the fluid channel upstream portion 12 U and the fluid channel downstream portion 12 D.
[0055] As shown in FIG. 1 , the divider 4 may be ribbon formed of solder, line-shaped brazed or soldered joint, or, metal plate. For example, the first fluid channel 12 may be closed in a width direction thereof, by the divider 4 . Once a pair of heat exchange plates 10 is assembled, the divider 4 may be presented as a line-shaped brazed or soldered joint closing the first fluid channel 12 in the width direction of the heat exchange plates 10 . For example, the divider 4 may be a projection formed, by pressing, on the heat exchange plate 10 , and then, the divider 4 closes the first fluid channel 12 by welding, brazing, or soldering.
[0056] As shown in FIG. 1 , the plate heat exchanger 100 further comprises the outlet 3 of the fluid channel upstream portion 12 U and the inlet 5 of the fluid channel downstream portion 12 D. The outlet 3 of the fluid channel upstream portion 12 U is fluidly communicated via the fluid communication device 15 with the inlet 5 of the fluid channel downstream portion 12 D. A plurality of outlets 3 of the fluid channel upstream portions 12 U constitute an upstream port chamber, and, a plurality of the inlets 5 of the fluid channel downstream portions 12 D constitute a downstream port chamber. The upstream port chamber and the downstream port chamber are connected to or directly to, or are fluidly communicated with or directly with, the fluid communication device. The outlets 3 of the fluid channel upstream portion 12 U and the inlets 5 of the fluid channel downstream portion 12 D are adjacent to the divider 4 and are provided respectively at both sides of the divider 4 . For example, in the length direction (the left-right direction in FIG. 1 ) of the heat exchange plate 10 or substantially in a flow direction of the fluid in the first fluid channel 12 , the outlets 3 and inlets 5 are provided respectively at both sides of the divider 4 . The outlets 3 of the fluid channel upstream portion 12 U and the inlets 5 of the fluid channel downstream portion 12 D are provided at the side of the heat exchange plate 10 and the fluid communication device 15 is provided at the side of the heat exchange plate 10 or the end plate 11 or 13 . For example, one or more fluid communication devices 15 are provided, or, the fluid communication devices 15 are provided at one side or both sides. The upstream port chamber and downstream port chamber are connected to or directly to one fluid communication device 15 at one side, or connected to or directly to two fluid communication devices 15 at both sides.
[0057] As shown in FIG. 1 , distance between the divider 4 and said inlet 1 of the first fluid channel may be about 50-80% of the length of said heat exchange plate 10 . The fluid channel upstream portion 12 U and fluid channel downstream portion 12 D are configured such that flow resistance of said fluid channel upstream portion 12 U is greater than that of said fluid channel downstream portion 12 D, or, flow resistance per unit length of said fluid channel upstream portion 12 U is greater than that of said fluid channel downstream portion 12 D. For example, inner wall surface of the fluid channel upstream portion 12 U may be a coarse one, while the fluid channel downstream portion 12 D may have a smooth surface.
[0058] As shown in FIG. 8 , the fluid communication device 15 may be embodied as channel, chamber, or fluid mixing chamber.
[0059] According to one example of the present invention, as shown in FIGS. 4 a to 7 , the plate heat exchanger 100 further comprises chamber plates 16 . The chamber plates 16 are disposed on the outer sides of the end plates 11 and 13 and have recesses 161 which, together with the corresponding portions of the outer sides of the end plates 11 and 13 , form chambers as the fluid communication devices 15 . The outlets 3 of the fluid channel upstream portion 12 U and the inlets 5 of the fluid channel downstream portion 12 D are fluidly communicated with the chambers. For example, the outlets 3 and the inlets 5 are fluidly communicated with the chambers, through openings, which correspond to the outlets 3 and the inlets 5 , on the end plates 11 and 13 . The corresponding portions are adjacent to the separation of the fluid channel upstream portion 12 U and the fluid channel downstream portion 12 D, or, are adjacent to the divider 4 . According to one example of the present invention, in the length direction (the left-right direction in FIG. 1 ) of the heat exchange plate 10 or substantially in the flow direction of the fluid in the first fluid channel 12 , the corresponding portions are at the location of the divider 4 .
[0060] According to another example of the present invention, the end plates 11 and 13 have recesses which, together with the corresponding portions of the outer sides of the heat exchange plates 10 , form chambers as the fluid communication devices 15 . The outlets 3 of the fluid channel upstream portion 12 U and the inlets 5 of the fluid channel downstream portion 12 D are fluidly communicated with the chambers. For example, the corresponding portions are adjacent to the separation of the fluid channel upstream portion 12 U and the fluid channel downstream portion 12 D, or, are adjacent to the divider 4 . According to one example of the present invention, in the length direction (the left-right direction in FIG. 1 ) of the heat exchange plate 10 or substantially in the flow direction of the fluid in the first fluid channel 12 , the corresponding portions are at the location of the divider 4 .
[0061] Referring to FIGS. 1 , 6 a , 6 b , 7 , and 8 , according to one example of the present invention, the fluid communication devices 15 or the recesses are adjacent to the separation of the fluid channel upstream portion and the fluid channel downstream portion, or, the fluid communication devices 15 or the recesses are adjacent to the divider 4 . In the length direction of the heat exchange plate 10 or substantially in the flow direction of the fluid in the first fluid channel 12 , the fluid communication devices 15 or the recesses are at the location of the divider 4 . In the length direction of the heat exchange plate 10 or substantially in the flow direction of the fluid in the first fluid channel 12 , for example, the recesses or the fluid communication devices 15 , or, the corresponding portions, go across the divider 4 .
[0062] As an alternative, the outlets 3 of the fluid channel upstream portion 12 U and the inlets 5 of the fluid channel downstream portion 12 D may be disposed at other locations, instead of being adjacent to the divider 4 .
[0063] In addition, the heat exchange plate 10 shown in FIG. 1 is an integral one and is separated by the divider 4 into two portions. As an alternative, the heat exchange plates for the first fluid channel 12 may be consisted of two separated portions.
[0064] As shown in FIGS. 1 , 2 , and 11 , once a pair of heat exchange plates 10 shown in FIG. 1 are assembled, the first fluid channel 12 is separated into two heat-transfer regions (i.e., the fluid channel upstream portion 12 U and the fluid channel downstream portion 12 D) that are not communicated directly while the second fluid channel is a communicated groove. Moreover, the outlets 3 of the fluid channel upstream portion 12 U and the inlets 5 of the fluid channel downstream portion 12 D and the second fluid channel are separated such that the fluid in the first fluid channel 12 and that in the second fluid channel, for example refrigerant and water, are separated. In addition, the upstream region may adopt structure of the channel with a relative larger pressure drop, and the downstream region may adopt structure of the channel with a moderate pressure drop.
[0065] As shown in FIGS. 1-8 , once a plurality of pairs of heat exchange plates 10 are assembled, the two outermost sides of the heat exchange plates 10 are mated with the end plates 11 and 13 . The ends plates 11 and 13 have the corresponding through holes respectively formed at the regions corresponding to the outlets 3 of the fluid channel upstream portion 12 U and the inlets 5 of the fluid channel downstream portion 12 D. Based on the above configuration, the ends plates 11 and 13 are connected with the chamber plates 16 . And, the chamber plates 16 are sealedly mated with the ends plates 11 and 13 . In this way, a closed flow path is formed between the outlets 3 of the fluid channel upstream portion 12 U and the inlets 5 of the fluid channel downstream portion 12 D, excepting the inlet 1 and the outlet 7 . The connection tubes are assembled to these above-mentioned components, to achieve the plate heat exchanger 100 . The achieved plate heat exchanger 100 may be assembled by a copper brazing processing or a nickel brazing processing.
[0066] Next, with reference to the flowing and heat-transfer process of the refrigerant, explanations of operational principle of the plate heat exchanger are provided
[0067] FIG. 8 is a schematically flowing view of the refrigerant in the heat exchanger. Referring to FIGS. 1 , 7 , and 8 , specifically, the refrigerant, after the throttle procedure by the expansion valve, enters the heat exchanger 100 in a gas-liquid two-phase manner, and is dispensed in a relative high flow rate into these paralleled first fluid channels 12 , to perform the heat exchange. Then, the refrigerant leaves the fluid channel upstream portions 12 U from the outlets 3 of the upstream region and enters the flow path of the upstream outlet port chamber. After that, the refrigerant is further mixed within the mixing chamber 15 on the end plate, and goes to the downstream heat exchanger region, i.e., the fluid channel downstream portion 12 D, through the downstream inlet port chamber. Finally, the refrigerant completes heat exchange in the downstream heat exchanger region (i.e., the fluid channel downstream portion 12 D) and leaves the heat exchanger 100 .
[0068] As to distribution of the refrigerant, mal-distribution of the pressure exists in the outlet port chamber of the conventional plate heat exchanger, such that every channel has different pressure difference between the inlet and the outlet, that is, the driving forces are different, which results in mal-distribution of the refrigerant. According to the present invention, the refrigerant channel is divided into two heat exchange regions. During the flow from upstream to downstream, the pressure difference among different channels is uniformed by mean of bidirectional flow in the upstream port chamber. And, further mixing of the refrigerant in the mixing chamber on the end plate and distribution of the refrigerant within the downstream port chamber in an impinging stream manner ensure uniform distribution of the refrigerant in every channel. In this way, on the one hand, the different pressure drops are meliorated and, difficulty of the distribution is reduced by performing distribution of the refrigerant within two regions separated from one refrigerant channel; on the other hand, provision of the mixing chamber enables that the refrigerant is remixed after one stage of the heat exchange process, which improves two-phase flow characteristic of the refrigerant at flow pattern and gas-fluid uniformity, to bring conditions for further high efficient heat exchange.
[0069] As to reinforcement of the heat exchange, for an evaporation process, the refrigerant enters the heat exchange channel in a relative small dryness and leaves the heat exchanger in the form of overheat steam, in which different heat exchange mechanisms are utilized in the heat exchange process. For a heat exchange process under a relative small dryness, nuclear boiling plays a leading role in the refrigerant heat exchange process. For a heat exchange process under a relative large dryness, convection boiling plays a leading role in the refrigerant heat exchange process. Nowadays, in the market, most of the conventional plate heat exchangers adopt a single channel configuration, which is not match up with heat exchange characteristic of the refrigerant. In the present invention, the refrigerant channel is divided into two independent heat exchange regions, i.e., an upstream region and a downstream region. Accordingly, the present invention brings matching solutions for both the nuclear boiling heat exchange mechanism and the convection boiling heat exchange mechanism. On the one hand, in the upstream region, the liquid refrigerant is broken up by a channel configuration with a relative great pressure drop, to reduce thickness of the fluid film and strengthen heat exchange of the nuclear boiling. On the other hand, in the downstream region, utilization of a channel configuration with a moderated pressure drop is match up with the convection boiling and reduces flow rate of the gas, to avoid excessive speed of the gas flow which leads to entraining of liquid droplet by the gas flow, so as to affect stability of the system and whole heat exchange effect. In all, the plate heat exchanger according to the present invention may achieve a high-effective heat exchange effect.
2 nd Embodiment
[0070] As shown in FIGS. 9 and 10 , for a wide plate heat exchanger 100 of relative small length breadth ratio, a rectangular flow opening or a plurality of flow openings may be adopted, to achieve communication between the upstream region and the downstream region and mixture, as shown in FIGS. 9 and 10 . That is, the outlet 3 of the first fluid channel upstream portion 12 U and the inlet 5 of the first fluid channel downstream portion 12 D both have a generally rectangular shape, or, the plate heat exchanger 100 have a plurality of outlets 3 of the first fluid channel upstream portion 12 U and a plurality of inlets 5 of the first fluid channel downstream portion 12 D.
3 rd Embodiment
[0071] The present invention is also suitable for a dual circuit evaporator. FIG. 11 shows a schematic view of a dual circuit refrigerant plate heat exchanger 100 . The plate heat exchanger 100 has two refrigerant circulating circuits which are heated commonly by one water circulating system. In FIG. 11 , W indicates a water circuit, R 1 indicates a first refrigerant circuit, and, R 2 indicates a second refrigerant circuit. The present invention provides a solution for such application as shown in FIG. 12 . For a single side-flow channel, number 1 denotes an inlet for a first refrigerant (first fluid inlet), numbers 3 and 5 denote upstream and downstream communication ports (an outlet of the first fluid channel upstream portion 12 U and an inlet of the first fluid channel downstream portion 12 D), number 7 denotes an outlet for the first refrigerant (first fluid outlet); number 1 ′ denotes an inlet for a second refrigerant (first fluid inlet), number 7 ′ denotes an outlet for the second refrigerant (first fluid outlet), number 6 denotes a water side inlet (second fluid inlet), and, number 2 denotes a water side outlet (second fluid outlet).
[0072] For a diagonal-flow channel, number 1 denotes an inlet for a first refrigerant (first fluid inlet), numbers 3 and 5 denote upstream and downstream communication ports (an outlet of the first fluid channel upstream portion 12 U and an inlet of the first fluid channel downstream portion 12 D), number 7 ′ denotes an outlet for the first refrigerant (first fluid outlet); number 1 ′ denotes an inlet for a second refrigerant (first fluid inlet), number 7 denotes an outlet for the second refrigerant (first fluid outlet), number 6 denotes a water side inlet (second fluid inlet), and, number 2 denotes a water side outlet (second fluid outlet).
[0073] Due to restrictions of water side pressure drop, the heat exchange plate at the upstream region of the refrigerant channel should adopt asymmetric configuration as far as possible, that is, the refrigerant side has a relative greater pressure drop while the water side has a relative less pressure drop.
[0074] In the above embodiments, it is described that the outlet 3 of the first fluid channel upstream portion 12 U and the inlet 5 of the first fluid channel downstream portion 12 D are fluidly communicated with the fluid communication device 15 or the mixing chamber. As to a plurality of first fluid channels 12 , a plurality of outlets 3 of the first fluid channel upstream portions 12 U and a plurality of inlets 5 of the first fluid channel downstream portions 12 D, all the plurality of first fluid channel upstream portions 12 U are communicated with all the plurality of outlets 3 , or, some of the plurality of first fluid channel upstream portions 12 U are communicated with some of the plurality of outlets 3 while the rest of the plurality of first fluid channel upstream portions 12 U are communicated with the rest of the plurality of outlets 3 ; and, all the plurality of the first fluid channel downstream portions 12 D are communicated with all the plurality of inlets 5 , or, some of the plurality of first fluid channel downstream portions 12 D are communicated with some of the plurality of inlets 5 while the rest of the plurality of first fluid channel downstream portions 12 D are communicated with the rest of the plurality of inlets 5 . As to the fluid communication device 15 , the outlets 3 and the inlets 5 may be communicated with each other, respectively. All the plurality of outlets 3 are communicated with all the plurality of inlets 5 , or, some of the plurality of outlets 3 are communicated with some of the plurality of inlets 5 , respectively or some of the plurality of outlets 3 are communicated with some of the plurality of inlets 5 , while the rest of the plurality of outlets 3 are communicated with the rest of the plurality of inlets 5 , respectively, or the rest of the plurality of outlets 3 are communicated with the rest of the plurality of inlets 5 . Obviously, the outlets 3 of the first fluid channel upstream portions 12 U and the inlets 5 of the first fluid channel downstream portions 12 D and the fluid communication device 15 may be communicated in any suitable manner. As to a multiple circuit system, the outlets 3 of the first fluid channel upstream portions 12 U and the inlets 5 of the first fluid channel downstream portions 12 D and the fluid communication device 15 in each circuit are not communicated with those in another circuit.
[0075] Although several exemplary embodiments have been shown and described, the present invention is not limited to these embodiments. For example, part(s) of the technical features in those exemplary embodiments may be combined with each other to form new exemplary embodiment(s). Moreover, the heat exchange plate may adopt other suitable configuration in which the first fluid channel 12 is separated into the fluid channel upstream portion and the fluid channel downstream portion. In addition, although the fluid communication device 15 is provided on the outer side of the heat exchange plate 10 or the end plates 11 and 13 as shown in the drawings, the fluid communication device 15 may also be provided within the heat exchanger, for example, the fluid communication device 15 is provided within a channel.
[0076] Moreover, once the fluid communication device 15 uses fluid passageway or pipeline, the outlet 3 of the first fluid channel upstream portion 12 U and the inlet 5 of the first fluid channel downstream portion 12 D may be disposed away from the divider 4 .
[0077] In addition, the above-mentioned chamber or the fluid mixing chamber may be any sealed chamber that is only fluidly communicated with the outlet 3 of the first fluid channel upstream portion 12 U and the inlet 5 of the first fluid channel downstream portion 12 D.
[0078] Although several exemplary embodiments have been shown and described, it would be appreciated by those skilled in the art that various changes or modifications may be made in these embodiments without departing from the principles and spirit of the disclosure, the scope of which is defined in the claims and their equivalents. | The prevent invention provides a plate heat exchanger. The plate heat exchanger comprises heat exchange plates each forms one or more first fluid channels and one or more second fluid channels. The one or more first fluid channels each has a fluid channel upstream portion and a fluid channel downstream portion separated from the fluid channel upstream portion, wherein the fluid channel upstream portion is fluidly communicated via a fluid communication device with the fluid channel downstream portion. The plate heat exchanger according to the present invention achieves uniform distribution of the refrigerant while being independent of the distributors, and, provides different heat exchange regions in the channels on the basis of heat-transfer mechanism correlated to refrigerant evaporation, to reinforce the heat transfer. The plate heat exchanger, without the distributors, according to the present invention not only reduces difficulties on productions and processes, but also, widens practical application scopes and conditions. In addition, as there is no distributor in the plate heat exchanger, compared with other similar products, the refrigerant stream has a lower total pressure drop, which brings more spaces for type selection of the expansion valve. | 5 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation application of U.S. patent application Ser. No. 10/801,276, now U.S. Pat. No. 8,111,820, filed Mar. 16, 2003, which is in-turn a continuation of U.S. patent application Ser. No. 10/135,323, filed Apr. 30, 2002, now U.S. Pat. No. 6,721,411, which is a non-provisional filing of U.S. Provisional Application No. 60/287,441, filed Apr. 30, 2001. Priority is claimed to each of these applications and the entire contents of each are incorporated herein by reference in their entirety.
BACKGROUND
The present invention relates to telephony and in particular to an audio conferencing platform.
Audio conferencing platforms are known. For example, see U.S. Pat. Nos. 5,483,588 and 5,495,522. Audio conferencing platforms allow conference participants to easily schedule and conduct audio conferences with a large number of users. In addition, audio conference platforms are generally capable of simultaneously supporting many conferences.
A problem with existing audio conference platforms is that they employ a fixed threshold to determine whether a conference participant is speaking. Using such a fixed threshold may result in a conference participant being added to the summed conference audio, even though they are not speaking. Specifically, if the background audio noise is high (e.g., the user is on a factory floor), then the amount of digitized audio energy associated with that conference participant may be sufficient for the conference platform to falsely detect speech, and add the background noise to the conference sum under the mistaken belief that the energy is associated with speech.
Therefore, there is a need for a system that accounts for background noise in the detection of valid conference speakers.
SUMMARY OF THE INVENTION
One object of the present invention is to provide a method and system that advantageously accounts for background noise on lines participating in a conference call and prevents the background noise from being added to the conference sum because an erroneous determination has been made that the energy is associated with speech. Another object is to provide such an advantage dynamically, to account for changing conditions on participating lines.
A preferred embodiment of the invention comprises an audio conferencing platform that includes a time division multiplexing (TDM) data bus, a controller, and an interface circuit that receives audio signals from a plurality of conference participants and provides digitized audio signals in assigned time slots over the data bus. The audio conferencing platform also includes a plurality of digital signal processors (DSPs) adapted to communicate on the TDM bus with the interface circuit. At least one of the DSPs sums a plurality of the digitized audio signals associated with conference participants who are speaking to provide a summed conference signal. This DSP provides the summed conference signal to at least one of the other plurality of DSPs, which removes the digitized audio signal associated with a speaker whose voice is included in the summed conference signal, thus providing a customized conference audio signal to each of the speakers.
Each of the digitized audio signals are processed to determine whether the digitized audio signal includes speech. For each digitized audio signal, the amount of energy associated with the digitized audio signal is compared against a dynamic threshold value associated with the line over which the audio signal is received. The dynamic threshold value is set as a function of background noise within the digitized audio signal.
The audio conferencing platform preferably configures at least one of the DSPs as a centralized audio mixer and at least another one of the DSPs as an audio processor. The centralized audio mixer performs the step of summing a plurality of the digitized audio signals associated with conference participants who are speaking, to provide the summed conference signal. The centralized audio mixer provides the summed conference signal to the audio processor(s) for post processing and routing to the conference participants. The post processing includes removing the audio associated with a speaker from the conference signal to be sent to the speaker. For example, if there are forty conference participants and three of the participants are speaking, then the summed conference signal will include the audio from the three speakers. The summed conference signal is made available on the data bus to the thirty-seven non-speaking conference participants. However, the three speakers each receive an audio signal that is equal to the summed conference signal less the digitized audio signal associated with that speaker. Removing the speaker's own voice from the audio he hears reduces echoes.
The centralized audio mixer also preferably receives DTMF detect bits indicative of the digitized audio signals that include a DTMF tone. The DTMF detect bits may be provided by another of the DSPs that is programmed to detect DTMF tones. If the digitized audio signal is associated with a speaker, but the digitized audio signal includes a DTMF tone, the centralized conference mixer will not include the digitized audio signal in the summed conference signal while that DTMF detect bit signal is active. This ensures that conference participants do not hear annoying DTMF tones in the conference audio. When the DTMF tone is no longer present in the digitized audio signal, the centralized conference mixer may include the audio signal in the summed conference signal.
The audio conference platform is preferably capable of supporting a number of simultaneous conferences (e.g., 384). As a result, the audio conference mixer provides a summed conference signal for each of the conferences.
Each of the digitized audio signals may be preprocessed. The preprocessing steps include decompressing the signal (e.g., using the well-known .mu.-law or A-law compression schemes), and determining whether the magnitude of the decompressed audio signal is greater than a detection threshold. If it is, then a speech bit associated with the digitized audio signal is set. Otherwise, the speech bit is cleared.
The centralized conference mixer reduces repetitive tasks distributed between the plurality of DSPs. In addition, centralized conference mixing provides a system architecture that is scalable and thus easily expanded.
Advantageously, using a dynamic threshold value to determine whether there is speech on a line helps to ensure that background noise is not falsely detected as speech.
Thus, a method in accordance with a preferred embodiment of the present invention comprises receiving audio signals over a plurality of ports. For at least one port, the method comprises determining a dynamic threshold value based on one or more characteristics of signals received on the port; associating said dynamic threshold value with the port; and comparing one or more characteristics of signals subsequently received on the port to the dynamic threshold value. The method further comprises summing signals received over the plurality of ports, wherein signals received on the at least one port whose characteristics (such as energy level) have a specified relationship to the dynamic threshold value (for example, having an energy level less than the threshold value) are not contained in the sum. The method may further comprise preprocessing audio signals by decompressing them using either .mu.-law or A-law decompression.
In one aspect, the method comprises identifying which ports are receiving audio signals that contain speech; and, on each such identified port, transmitting a summed signal, wherein said summed signal does not contain signals received on that port.
In another aspect, the method comprises identifying which ports are receiving audio signals that contain DTMF tones; and, on each such identified port, transmitting a summed signal, wherein said summed signal does not contain signals received on that port. Preferably, the step of identifying comprises setting a DTMF detect bit for a signal. The method may also comprise the step of including signals from previously identified ports in the sum after those ports are no longer identified as receiving signals containing one or more DTMF tones.
The invention further comprises software and systems for implementing methods described herein.
These and other objects, features, and advantages of the present invention will become apparent in light of the following detailed description of preferred embodiments thereof, as illustrated in the accompanying drawings.
Although the invention has been described in connection with an audio conferencing platform, it is not limited to such a platform and may be used, for example, in a video conferencing system.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates a conferencing system in accordance with a preferred embodiment of the present invention;
FIG. 2 illustrates a functional block diagram of an audio conferencing platform of a preferred embodiment within the conferencing system of FIG. 1 ;
FIG. 3 is a block diagram illustration of a processor board of a preferred embodiment within the audio conferencing platform of FIG. 2 ;
FIG. 4 is a functional block diagram illustration of resources on the processor board of FIG. 3 ;
FIG. 5 is a flow chart illustrating the processing of signals received from network interface cards over a TDM bus;
FIG. 6 is a flow chart illustration of the DTMF tone detection processing;
FIGS. 7A-7B together provide a flow chart illustration of preferred conference mixer processing to create a summed conference signal; and
FIG. 8 is a flow chart illustrating the processing of signals to be output to the network interface cards via the TDM bus.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is a diagram of a conferencing system 20 in accordance with a preferred embodiment of the present invention. The system 20 connects a plurality of user sites 21 - 23 through a switching network 24 to an audio conferencing platform 26 . The plurality of user sites may be distributed worldwide, or at a company facility/campus. For example, each of the user sites 21 - 23 may be in different cities and connected to the audio platform 26 via the switching network 24 , which may include PSTN and PBX systems. The connections between the user sites and the switching network 24 may include T1, E1, T3, and ISDN lines.
Each user site 21 - 23 preferably includes one or more telephones 28 and one or more personal computers or servers 30 . However, a user site may only include either a telephone, such as user site 21 a , or a computer/server, such as user site 23 a . The computer/server 30 may be connected via an Internet/intranet backbone 32 to a server 34 . The audio conferencing platform 26 and the server 34 are connected via a data link 36 (e.g., a 10/100 Base T Ethernet link). The computer 30 allows the user to participate in a data conference simultaneous to the audio conference via the server 34 . In addition, the user can use the computer 30 to interface (e.g., via a browser) with the server 34 to perform functions such as conference control, administration (e.g., system configuration, billing, reports, . . . ), scheduling and account maintenance. The telephone 28 and the computer 30 may cooperate to provide voice over the Internet/intranet 32 to the audio conferencing platform 26 via the data link 36 .
FIG. 2 is a functional block diagram of an audio conferencing platform 26 in accordance with a preferred embodiment of the present invention. The audio conferencing platform 26 includes a plurality of network interface cards (NICs) 38 - 40 that receive audio information from the switching network 24 (see FIG. 1 ). Each NIC is preferably capable of handling a plurality of different trunk lines (e.g., eight). The data received by the NIC is generally an 8-bit .mu.-law or A-law sample. The NIC places the sample into a memory device (not shown), which is used to output the audio data onto a data bus. The data bus is preferably a TDM bus based, in one embodiment, upon the H.110 telephony standard.
The audio conferencing platform 26 also includes a plurality of processor boards 44 - 46 that receive and transmit data to the NICs 38 - 40 over the TDM bus 42 . The NICs and the processor boards 44 - 46 also communicate with a controller/CPU board 48 over a system bus 50 . The system bus 50 is preferably based upon the Compact Peripheral Component Interconnect (“cPCI”) standard. The CPU/controller communicates with the server 34 (see FIG. 1 ) via the data link 36 . The controller/CPU board may include a general purpose processor such as a 200 MHz Pentium™ CPU manufactured by Intel Corporation, a processor from AMD or any other similar processor (including an ASIC) having sufficient processor speed (MIPS) to support the present invention.
FIG. 3 is block diagram illustration of the processor board 44 . The board 44 includes a plurality of dynamically programmable digital signal processors 60 - 65 . Each digital signal processor (DSP) is an integrated circuit that communicates with the controller/CPU card 48 (see FIG. 2 ) over the system bus 50 . Specifically, the processor board 44 includes a bus interface 68 that interconnects the DSPs 60 - 65 to the system bus 50 . Each DSP also includes an associated dual port RAM (DPR) 70 - 75 that buffers commands and data for transmission between the system bus 50 and the associated DSP.
Each DSP 60 - 65 also transmits data over and receives data from the TDM bus 42 . The processor card 44 includes a TDM bus interface 78 that performs any necessary signal conditioning and transformation. For example, if the TDM bus is an H.110 bus, it includes thirty-two serial lines. As a result the TDM bus interface may include a serial-to-parallel and a parallel-to-serial interface.
Each DSP 60 - 65 also includes an associated TDM dual port RAM 80 - 85 that buffers data for transmission between the TDM bus 42 and the associated DSP.
Each of the DSPs is preferably a general purpose digital signal processor IC, such as the model number TMS320C6201 processor available from Texas Instruments. The number of DSPs resident on the processor board 44 is a function of the size of the integrated circuits, their power consumption, and the heat dissipation ability of the processor board. For example, in certain embodiments there may be between four and ten DSPs per processor board.
Executable software applications may be downloaded from the controller/CPU 48 (see FIG. 2 ) via the system bus 50 to a selected one(s) of the DSPs 60 - 65 . Each of the DSPs is preferably also connected to an adjacent DSP via a serial data link.
FIG. 4 is illustrates the DSP resources on the processor board 44 illustrated in FIG. 3 . Referring to FIGS. 3 and 4 , the controller/CPU 48 (see FIG. 2 ) downloads executable program instructions to a DSP based upon the function that the controller/CPU assigns to the DSP. For example, the controller/CPU may download executable program instructions for the DSP 3 62 to function as an audio conference mixer 90 , while the DSP 2 61 and the DSP 4 63 may be configured as audio processors 92 , 94 , respectively. Other DSPs 60 , 65 may be configured by the controller/CPU 48 (see FIG. 2 ) to provide services such as DTMF detection 96 , audio message generation 98 and music playback 100 .
Each audio processor 92 , 94 is capable of supporting a certain number of user ports (i.e., conference participants). This number is based upon the operational speed of the various components within the processor board and the over-all design of the system. Each audio processor 92 , 94 receives compressed audio data 102 from the conference participants over the TDM bus 42 .
The TDM bus 42 may, for example, support 4096 time slots, each having a bandwidth of 64 kbps. The timeslots are generally dynamically assigned by the controller/CPU 48 (see FIG. 2 ) as needed for the conferences that are currently occurring. However, one of ordinary skill in the art will recognize that in a static system the timeslots may be predetermined.
FIG. 5 is a flow chart illustrating the processing steps 500 performed by each audio processor on the digitized audio signals received over the TDM bus 42 from the NICs 38 - 40 (see FIG. 2 ). The executable program instructions associated with these processing steps 500 are typically downloaded to the audio processors 92 , 94 (see FIG. 4 ) by the controller/CPU 48 (see FIG. 2 ). The download may occur during system initialization or reconfiguration. These processing steps 500 preferably are executed at least once every 125 microseconds to provide audio of the requisite quality.
For each of the active/assigned ports for the audio processor, step 502 reads the audio data for that port from TDM dual port RAM associated with the audio processor. For example, if DSP 2 61 (see FIG. 3 ) is configured to perform the function of audio processor 92 (see FIG. 4 ), then the data is read from the read bank of the TDM dual port RAM 81 . If the audio processor 92 is responsible for, for example, 700 active/assigned ports, then step 502 reads the 700 bytes of associated audio data from the TDM dual port RAM 81 . Each audio processor includes a time slot allocation table (not shown) that specifies the address location in the TDM dual port RAM for the audio data from each port.
Since each of the audio signals is typically compressed (e.g., .mu.-law, A-law), step 504 decompresses each of the 8-bit signals to a 16-bit word. Step 506 computes the average magnitude (AVM) for each of the decompressed signals associated with the ports assigned to the audio processor. For additional details, see co-pending U.S. patent application Ser. No. 09/532,602, filed Mar. 22, 2000, entitled “Scalable Audio Conference Platform,” the entire contents of which are incorporated herein by reference for all purposes.
Step 508 is performed to determine which of the ports are speaking. This step compares the average magnitude for the port computed in step 506 against a predetermined magnitude value representative of speech (e.g., −35 dBm). If average magnitude for the port exceeds the predetermined magnitude value representative of speech, a speech bit associated with the port is set. Otherwise, the associated speech bit is cleared. Each port has an associated speech bit. Step 510 outputs all the speech bits (eight per timeslot) onto the TDM bus. Step 512 is performed to calculate an automatic gain correction (AGC) value for each port. To compute an AGC value for the port, the AVM value is converted to an index value associated with a table containing gain/attenuation factors. For example, there may be 256 index values, each uniquely associated with 256 gain/attenuation factors. The index value is used by the conference mixer 90 (see FIG. 4 ) to determine the gain/attenuation factor to be applied to an audio signal that will be summed to create the conference sum signal.
In a preferred embodiment, the threshold used in step 508 to determine whether speech is present is a dynamic speech detection threshold value, set as a function of the noise detected on the line. For example, if the magnitude for the energy for the line/port exceeds a noise detection threshold value for a predetermined amount of time (e.g., three seconds), then noise is detected and a higher threshold value may be used in step 510 to determine whether the user is speaking. Once noise has been detected, the dynamic threshold value may be set as a function of the magnitude of the energy on the line. For example, the dynamic threshold value may be set to a certain value greater than the value of the noise on the line (e.g., the average noise). Each line may employ a different speech detection threshold, since the background noise on each of the lines may be different.
The system may also set a noise bit for the line, and the noise bit may be provided to the controller/CPU 48 (see FIG. 2 ) to take the necessary action due to the background noise. The action may include not allowing this conference participant to be on the speech list (i.e., the list of lines summed to create the conference signal), or sending an audio message to the conference participant that the system detects high background noise and recommends that the conference participant try to take corrective action (e.g., move to a different area, close an office door, go off speaker phone, etc.).
Additional action may include sending an audio message to the conference participant that the system detects high background noise and instructing the participant to hit a key on the telephone keypad so the system does not consider the audio from the participant for the conference audio. The system would then detect the DTMF tone associated with the key being depressed and take the necessary action to prevent audio from this participant from being used in the conference sum, until such time that the user, for example, hits the same key again or another key instructing the system to consider audio from the participant for the conference sum.
FIG. 6 is a flow chart illustration of the DTMF tone detection processing 600 . These processing steps 600 are performed by the DTMF processor 96 (see FIG. 4 ), preferably at least once every 125 microseconds, to detect DTMF tones within digitized audio signals from the NICs 38 - 40 ( FIG. 2 ). One or more of the DSPs may be configured to operate as a DTMF tone detector. The executable program instructions associated with the processing steps 600 are typically downloaded by the controller/CPU 48 (see FIG. 2 ) to the DSP designated to perform the DTMF tone detection function. The download may occur during initialization or system reconfiguration.
For an assigned number of the active/assigned ports of the conferencing system, step 602 reads the audio data for the port from the TDM dual port RAM associated with the DSP(s) configured to perform the DTMF tone detection function. Step 604 then expands the 8-bit signal to a 16-bit word. Next, step 606 tests each of these decompressed audio signals to determine whether any of the signals includes a DTMF tone. For any signal that does include a DTMF tone, step 606 sets a DTMF detect bit associated with the port. Otherwise, the DTMF detect bit is cleared. Each port has an associated DTMF detect bit. Step 608 informs the controller/CPU 48 (see FIG. 3 ) through Dual Port Ram (DPR) which DTMF tone was detected, since the tone is representative of system commands and/or data from a conference participant. Step 610 outputs the DTMF detect bits onto the TDM bus.
FIGS. 7A-7B collectively provide a flow chart illustrating processing steps 700 performed by the audio conference mixer 90 (see FIG. 4 ), preferably at least once every 125 microseconds, to create a summed conference signal for each conference. The executable program instructions associated with the processing steps 700 are typically downloaded by the controller/CPU 48 (see FIG. 2 ) over the system bus 50 (see FIG. 2 ) to the DSP designated to perform the conference mixer function. The download may occur during initialization or system reconfiguration.
Referring to FIG. 7A , for each of the active/assigned ports of the audio conferencing system, step 702 reads the speech bit and the DTMF detect bit received over the TDM bus 42 (see FIG. 4 ). Alternatively, the speech bits may be provided over a dedicated serial link that interconnects the audio processor or processors and the conference mixer. Step 704 is then performed to determine whether the speech bit for the port is set (i.e., whether energy that may be speech is detected on that port). If the speech bit is set, then step 706 is performed to see whether the DTMF detect bit for the port is also set. If the DTMF detect bit is clear, then the audio received by the port is speech and the audio does not include DTMF tones. As a result, step 708 sets the conference bit for that port; otherwise, step 709 clears the conference bit associated with the port. Since the audio conferencing platform 26 (see FIG. 1 ) preferably can support many simultaneous conferences (e.g., 384), the controller/CPU 48 (see FIG. 2 ) keeps track of the conference that each port is assigned to and provides that information to the DSP performing the audio conference mixer function. Upon the completion of step 708 , the conference bit for each port has been updated to indicate the conference participants whose voice should be included in the conference sum.
Referring to FIG. 7B , for each of the conferences, step 710 is performed, if needed, to decompress each of the audio signals associated with conference bits that are set. Step 711 performs AGC and gain/TLP (Test Level Point) compensation on the expanded signals from step 710 . Step 712 is then performed to sum each of the compensated audio samples to provide a summed conference signal. Since many conference participants may be speaking at the same time, the system preferably limits the number of conference participants whose voice is summed to create the conference audio. For example, the system may sum the audio signals from a maximum of three speaking conference participants. Step 714 outputs the summed audio signal for the conference to the audio processors, as appropriate. In a preferred embodiment, the summed audio signal for each conference is output to the audio processor(s) over the TDM bus. Since the audio conferencing platform supports a number of simultaneous conferences, steps 710 - 714 are performed for each of the conferences.
FIG. 8 is a flow chart illustrating the processing steps 800 performed by each audio processor to output audio signals over the TDM bus to conference participants. The executable program instructions associated with these processing steps 800 are typically downloaded to each audio processor by the controller/CPU during system initialization or reconfiguration. These steps 800 are also preferably executed at least once every 125 microseconds.
For each active/assigned port, step 802 retrieves the summed conference signal for the conference that the port is assigned to. Step 804 reads the conference bit associated with the port, and step 806 tests the bit to determine whether audio from the port was used to create the summed conference signal. If it was, then step 808 removes the gain (e.g., AGC and gain/TLP) compensated audio signal associated with the port from the summed audio signal. This step removes the speaker's own voice from the conference audio. If step 806 determines that audio from the port was not used to create the summed conference signal, then step 808 is bypassed. To prepare the signal to be output, step 810 applies a gain, and step 812 compresses the gain corrected signal. Step 814 then outputs the compressed signal onto the TDM bus for routing to the conference participant associated with the port, via the NIC (see FIG. 2 ).
Preferably, the audio conferencing platform 26 (see FIG. 1 ) computes conference sums at a central location. This reduces the distributed summing that would otherwise need to be performed to ensure that the ports receive the proper conference audio. In addition, the conference platform is readily expandable by adding additional NICs and/or processor boards. That is, the centralized conference mixer architecture allows the audio conferencing platform to be scaled to the user's requirements.
One of ordinary skill will appreciate that the overall system design is a function of the processing ability of each DSP. For example, if a sufficiently fast DSP is available, then the functions of the audio conference mixer, the audio processor and the DTMF tone detection and the other DSP functions may be performed by a single DSP.
In addition, although the aspect of the dynamic threshold value has been discussed in the context of a system that employs a centralized summing architecture, one of ordinary skill in the art will recognize that dynamic thresholding is certainly not limited to systems with a centralized summing architecture. It is contemplated that all audio conferencing systems, and systems with similar audio capabilities, would enjoy the benefits associated with employing a dynamic threshold value for determining whether a line includes speech.
Although the present invention has been shown and described with respect to several preferred embodiments thereof, various changes, omissions and additions to the form and detail thereof, may be made therein, without departing from the spirit and scope of the invention. | The present invention comprises a method for audio/video conferencing. In a preferred embodiment, the method comprises using a dynamic threshold value to determine whether there is speech on a line. One aspect, the method comprises determining a dynamic threshold value based on one or more characteristics of signals received on a port, associating that dynamic threshold value with the port; and comparing one or more characteristics of signals subsequently received on the port to the dynamic threshold value. Signals received over a plurality of ports are summed, but for ports whose signal characteristics have a specified relationship to the dynamic threshold value associated with that port, signals are not contained in the sum. | 7 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to drain outlets for public streets and roadways. More particularly, the present invention relates to a curb and gutter frame and funnel drain structure that may be installed in conjunction with standard concrete curb and gutter forms and that can be adapted to accommodate a variety of underground drain pipe configurations.
2. Description of the Related Art
In the prior art representatively shown in FIGS. 1 and 2, standard cast iron grates 100 and frames 102 are installed with curbs and gutters in a two-step process. Prior to the pouring of the curb 104 , brick masons construct a masonry chimney 106 directly over the drain pipe 108 for each frame and grate. When the appropriate elevation of each masonry chimney 106 is reached, a cast iron frame 102 and grate 100 is mounted thereon. When this work is completed, the standard curb and gutter forms are set around the frame and grate. Because this work is done in two steps, it is difficult to match the elevations of the masonry work with the drain slopes.
Furthermore, when pouring the concrete in the curb form, a section of the form must be left open on either side of the frame and grate due to the fact that a standard curb and gutter paving machine cannot pave over the previously installed cast iron frame and grate. As a result, the sections 110 on either side of the frame 102 and grate 100 must be hand troweled in by a later process. This not only incurs additional labor and expense, but also creates an expansion joint 112 in the paving near the grate. This joint near the grate is often a weak area that may separate under heavy loads.
Representative prior art is shown in U.S. Pat. Nos. 329,404, 783,740, 1,473,551, 1,664,853, 2,537,654, 2,809,414, 4,610,566, and 4,986,693.
SUMMARY OF THE INVENTION
In view of the foregoing, it is an object of the present invention to provide a one-piece curb and gutter frame and funnel drain that can be installed directly in a standard concrete curb and gutter form with the frame having the same upper profile as the form, enabling a standard curb and gutter paving machine to pour the curb with the frame and funnel drain in place in the form, thus eliminating the need to hand trowel on either side of the curb and gutter frame.
Another object of the invention is a frame and grate that may be installed without prior concrete work or preparation, and which can be installed concurrently with pouring of the curb and gutter.
A further object of the invention is a curb and gutter funnel drain oriented in non-vertical alignment with the frame and grate, allowing future repair to the drain without disturbance to the adjacent street and curb.
A still further object of the invention is a frame and funnel drain structure that can be adapted to accommodate a variety of drain pipe connection configurations.
In accordance with the foregoing and other objects, the present invention comprises a metal frame and funnel drain fabricated into a single welded structure. The funnel drain can be constructed in a number of ways so as to accommodate any type or shape of curb and gutter funnel outlet. The funnel drain is compatible with a full line of bolt-on attachments, including elbows, funnel extensions and saddle fittings, which connect to each other with standard corrugated metal pipe hugger bands. Through selection and adjustment of these attachments, the funnel drain may be effectively connected to a variety of drain pipe configurations, including those offset so as to be out of vertical alignment with the frame.
In addition to the adaptability of the configuration of the one-piece frame and funnel drain to fit various pipe orientations, the one-piece frame and funnel drain of the present invention also offers advantages in installation. The one-piece frame and funnel drain may be installed within any standard curb and gutter form. When installed in a curb and gutter form of the same style as the frame, a standard curb and gutter paving machine can pave directly up to the side panels of the frame. Furthermore, no preparatory concrete work is required to install the frame and funnel drain unit. Instead, concrete is poured with the one-piece unit in the form, so that curb and gutter installation and drain pipe installation may be accomplished simultaneously, saving both time and money over prior art methods.
These together with other objects and advantages which will become subsequently apparent reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part hereof, wherein like numerals refer to like parts throughout.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a top view of a prior art cast iron grate and frame as installed in a curb;
FIG. 2 is a cross-sectional view along line 2 — 2 in FIG. 1 showing the prior art brick masonry base as built upon a drainage pipe to support the iron grate and frame;
FIG. 3 is a top view of a one-piece frame and funnel drain in accordance with the present invention, as installed in a standard curb with a grate in place;
FIG. 4 is a cutaway side view along line 4 — 4 in FIG. 3 showing the one-piece frame and funnel drain as installed, with a funnel extension connected to a drainage pipe with a saddle fitting;
FIG. 5 is a cutaway side view along line 4 — 4 in FIG. 3 showing the one-piece frame and funnel drain as installed, with an alternate funnel extension orientation;
FIG. 6A is a cutaway side view along line 4 — 4 in FIG. 3 showing another alternative construction of the one-piece frame and funnel drain as installed, the frame having an extendable rectangular sleeve fitting welded thereto which is connected to a drainage pipe with a saddle fitting;
FIG. 6B is a side view of the alternative construction of the one-piece frame and funnel drain of FIG. 6A;
FIG. 6C is a front view of the alternative construction of the one-piece frame and funnel drain of FIG. 6B;
FIG. 7A is a top view of a second alternative construction of the one-piece frame and funnel drain of the present invention, shown with a grate and mounted in a curb and gutter form;
FIG. 7B is a side elevational view along line 7 B— 7 B in FIG. 7A, showing a 900 circular funnel drain designed to fit in the lid of a pre-cast concrete junction box;
FIG. 8A is a top view of the one-piece frame and funnel drain shown in FIG. 7A, without the grate;
FIG. 8B is a cross-sectional view along line 8 B— 8 B in FIG. 8A, showing the steps on the inner surface of the circular funnel drain;
FIG. 9 is a front perspective exploded view of the one-piece frame and funnel drain of FIGS. 7A-7B, with the pre-cast concrete junction box and lid;
FIG. 10 is a front perspective view of the one-piece frame and funnel drain of the present invention shown in FIGS. 3-5 but without a grate;
FIG. 11A is a front perspective view of a 90° 2′6″ frame style in accordance with the present invention, shown without concrete;
FIG. 11B is a front perspective view of the 90° 2′6″ frame style of FIG. 11A, shown with concrete;
FIG. 12A is a front perspective view of a shoulder berm frame style in accordance with the present invention, shown without concrete;
FIG. 12B is a front perspective view of the shoulder berm frame style of FIG. 12A, shown with concrete;
FIG. 13A is a front perspective view of an “S” style transversible curb frame style in accordance with the present invention, shown without concrete;
FIG. 13B is a front perspective view of the “S” style transversible curb frame style of FIG. 13A, shown with concrete;
FIG. 14A is a side view of a standard 90° 2′6″ curb and gutter form;
FIG. 14B is a side view of a 36″ shoulder berm gutter form; and
FIG. 14C is a side view of an “S” style transversible curb form.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
In describing preferred embodiments of the invention illustrated in the drawings, specific terminology will be resorted to for the sake of clarity. However, the invention is not intended to be limited to the specific terms so selected, and it is to be understood that each specific term includes all technical equivalents which operate in a similar manner to accomplish a similar purpose.
Referring now more specifically to the drawings, FIGS. 3 and 4 illustrate a preferred embodiment of the one-piece curb and gutter frame and funnel drain of the present invention, generally designed by the reference numeral 10 . A frame, generally designated by the reference numeral 12 , is fixedly connected to a funnel drain, generally designated by the reference numeral 14 . In each of the preferred embodiments discussed herein, the frame 12 and funnel drain 14 are preferably constructed of welded steel with a galvanized coating to ensure long life. As used herein, “funnel drain” is intended to refer generally to any drain which may be welded to the frame in accordance with the present invention and thus is not limited to drains having a customary “funnel” shape.
The frame 12 has a front panel 16 , two side panels 18 and a rear panel 20 . The rear panel 20 is taller than the front panel 16 in order to form a curb. Each side panel 18 rises upwardly near the rear panel 20 ; the slope of the rise varies depending on the curb form being matched by the frame 12 . A curb hood 22 is formed between the uppermost rear surfaces of each side panel 18 and the top of the rear panel 20 , extending toward the front panel, and having a shape and curvature consistent with the style of curb within which the particular one-piece unit 10 is intended to be installed.
The front panel 16 abuts the road surface 24 and gravel base 26 being drained by the one-piece frame and funnel drain 10 . A connecting structure such as a plurality of reinforcement studs 28 extend outwardly from each side panel 18 of the frame 12 in order to secure the frame 12 to the concrete paving 30 . In the preferred embodiments, these studs 28 comprise welded rebar pegs; however, other connecting elements can be used in accordance with the present invention. While not shown in FIG. 4, the frame also preferably includes a plurality of dowels 32 extending outwardly from the front panel 16 and the rear panel 20 of the frame for securing the frame to a curb and gutter form when pouring the concrete. Other structures for securing the frame in the form could also be used.
A grate 34 may be installed on the upper side of the frame 12 . Alternatively, the upper side of the frame 12 may be contoured with concrete as described more fully hereinafter. In the embodiment shown in FIGS. 3 and 4, the bottom of the frame has a sloped drain surface 82 , to the rear of which is a frame drain opening 84 . The frame drain opening 84 is accessible to the funnel drain 14 below and is normally directly above the top of the funnel drain 14 . In this embodiment, no concrete contouring is necessary and the upper side of the frame supports the grate 34 .
The funnel drain 14 shown in FIG. 4 is a sloped and tapered funnel drain that extends downwardly and rearwardly from the underside of the frame 12 into the supporting earth 36 . The upper end of the funnel drain 14 is fixedly connected to the underside of the frame 12 . Points of connection with the underside of the frame 12 preferably include the lower edge of the rear panel 20 , lower edge portions of the side panels 18 , and/or the bottom surface 82 . The funnel drain 14 is connected to the underside of the frame preferably by welding, but other suitable techniques for joining metal objects can also be used. During manufacture, the funnel drain can be welded to the frame at any angle to accommodate particular construction needs. Alternatively, the frame 12 and funnel drain 14 can be manufactured separately and then bolted together prior to or during installation in the field. With such a bolting arrangement, variation in the angle between the frame and the funnel drain can be accommodated through alternative bolt positions.
A particular advantage to the sloped and tapered funnel drain 14 is that it allows the drain pipe to be out of vertical alignment with the frame and funnel drain 10 and associated concrete paving. By offsetting of the drain pipe, the funnel drain may be connected to the drain pipe after the curb has been poured. In addition, many future repairs to the drain system may be effected without disturbing the adjacent street and curb.
A funnel extension 38 is coupled to the lower end of the funnel drain 14 with a connector band 40 . The other end of the funnel extension 38 is connected to a drainage pipe 42 using a saddle fitting 44 . Variation in the positioning of the drainage pipe 42 , shown by dotted lines as drainage pipe 42 ′, may be accommodated by orienting the funnel drain 14 differently, relative to the frame 12 , when initially connecting the drain 14 to the frame 12 to construct the one-piece frame and funnel drain 10 . Drainage pipe 42 ′ may also be accommodated through the use of a variety of funnel extensions and attachments, such as shown in FIG. 5 .
Looking now to FIG. 5, an elbow fitting 46 may be connected between the lower end of the funnel drain 14 and the funnel extension 38 , and secured with hugger bands 48 . Other structures suitable for connecting the fitting and drain structures may also be used.
An alternative embodiment of the one-piece frame and funnel drain 10 is shown in FIGS. 6A-6C. An extendable rectangular sleeve fitting, generally designated by the reference numeral 50 , is welded to the frame 12 and acts as the funnel drain. The extendable rectangular sleeve 50 has an inner portion 52 and an outer portion 54 . The outer portion 54 is sized to receive the inner portion 52 and includes a slot 56 .
In this alternative embodiment, the inner portion 52 is welded to the underside of the frame 12 , preferably at an angle approximately perpendicular thereto. The outer portion 54 tapers at the bottom and is connected to the drainage pipe 42 with a saddle fitting 44 . The depth of insertion of the inner portion 52 within the outer portion 54 , and hence the distance between the underside of the frame 12 and the drainage pipe 42 , is adjustable. When the inner portion 52 is at the desired insertion depth, the bolt 58 that passes through the slot 56 is tightened to secure the inner portion 52 against the outer portion 54 .
A second alternative embodiment is shown in FIGS. 7A-7B. FIG. 7A shows a top view and FIG. 7B shows a side elevational view of the frame and funnel drain 10 with a circular drain 68 as installed in a curb and gutter form, generally designated by the reference numeral 60 . The curb and gutter form 60 includes front and rear longitudinal members 62 joined by cutter plates 64 . The cutter plates 64 are used to form expansion joints in the poured concrete. The shape of the cutter plates 64 determines the contour of the concrete when it is poured, as further illustrated in FIGS. 14A-C. Before the concrete is poured, the form 60 is anchored to the ground using metal rods or stakes (not shown) through anchor loops 66 .
The frame and funnel drain 10 is mounted in the form 60 using the dowels 32 which are inserted through holes in the longitudinal members 62 . After the concrete paving 30 sets, the cutter plates 64 are removed and the longitudinal members 62 are pulled outwardly off the dowels 32 . The frame is secured to the set concrete paving 30 on either side by the reinforcement studs 28 . A grate 34 is placed over the frame 12 to cover the top of the circular drain 68 . In this second alternative embodiment, the lower end of the circular drain 68 is designed to fit into a pre-cast concrete box lid 70 for a concrete junction box 72 , as shown in FIG. 9 .
In FIGS. 8A and 8B, top and cross-sectional views, respectively, of the frame and funnel drain of FIG. 7A are shown with the grate 34 removed. Mounted on the inner surface of the circular drain 68 are preferably a plurality of manhole steps 74 . When the grate is removed, these manhole steps 74 allow entrance into the concrete junction box 72 located beneath the drain 68 . Side support shelves 76 , located on the inner surface of each side panel 18 of the frame, as well as a front support shelf 78 on the inner surface of the front panel 16 , support the grate 34 when installed. In a preferred embodiment, each side support shelf 76 includes an upwardly extending rear stop 80 (see FIG. 10) that prevents the grate from moving too far rearward, ensuring that the front edge of the grate remains immediately adjacent the front panel 16 of the frame 12 and supported on shelf 78 .
FIG. 9 shows a front perspective view of the frame 12 with circular drain 68 , according to the second alternative embodiment. As shown, the circular drain 68 is sized to fit within the circular opening 73 of the pre-cast concrete box lid 70 and can be rotated within such lid. This rotational capability allows the present invention to accommodate a curb and gutter arrangement that is not parallel with the concrete junction box 72 , offering a significant advantage over the prior art bricked masonry chimney technique. A center area 71 of each of the four sides of the concrete junction box 72 can be punched out to access drain lines from four directions.
Looking now to FIG. 10, a front perspective view of the embodiment of the frame and funnel drain 10 shown in FIGS. 3-5, 10 as adapted for use with a grate, shows the sloped drain surface 82 of the frame 12 . When the frame and funnel drain 10 has been installed, the grate 34 is placed over the sloped drain surface 82 and supported on either side by side support shelves 76 . The grate is prevented from moving rearward by the upwardly extending rear stops 80 . Drainage water flows through the frame drain opening 84 , at the rear of the sloped drain surface 82 , in the bottom of the frame, where it is directed through the funnel drain 14 . The curb hood 22 prevents debris or other materials from falling directly into the frame drain opening 84 from above.
The embodiments depicted in FIGS. 4, 6 A- 6 C and 7 A- 7 B represent three preferred embodiments of the frame and funnel drain 10 of the present invention. In the figures illustrating each of these embodiments, the frame 12 is shown as a 90° 2′6″ frame, with the style of the funnel drain 14 varying and thus distinguishing the three embodiments. However, each of the funnel drain styles shown could be paired with an alternative frame style, according to particular need. For example, the sloped and tapered funnel drain 14 of FIG. 4 could be combined with a shoulder berm frame style or with an “S” frame style. Similarly, the extendable rectangular sleeve 50 of FIGS. 6A-6C could be combined with a shoulder berm frame or with an “S” style curb frame, and so on. A particular frame style is selected on the basis of the curb form within which the frame and funnel drain is to be installed, while the choice of drain style is dependent upon the drainage pipe configuration or other considerations. The present invention includes any combination of frame and drain styles, welded together to form a one-piece steel structure. The frame and funnel drain combinations shown herein are thus illustrative only and are intended to demonstrate some of the many constructions that are possible.
Looking in greater detail at particular frame styles, FIGS. 11A and 11B are front perspective views of a 90° 2′6″ frame 12 according to the present invention, as constructed for concrete contouring; the funnel drain 14 is not shown. As shown by the frame 12 without concrete in FIG. 11A, the bottom 86 of the frame includes an upwardly and rearwardly extending rear edge 88 . On the top of each side of the upwardly extending rear edge 88 , there preferably is an upwardly extending fin 90 that abuts the respective side panel 18 and slopes downwardly toward the center of the rear edge 88 . A plurality of reinforcement rods 92 extend laterally between the side panels 18 . Concrete is poured into the frame and contoured to be flush with the top edges of the front panel 16 and side panels 18 , sloping downward toward the middle of the rear edge 88 , as shown in FIG. 11B; preferably, the slope is approximately 2:1. The fins 90 ensure a downward slope is achieved from the top edge of either side panel 18 toward the middle of the rear edge 88 . The concrete, when set into the contoured concrete drain surface 94 , is strengthened by the reinforcement rods 92 . When installed, the top edges of the side panels 18 and front panel 16 are flush with the surrounding paving. This allows the water to flow directly into the contoured concrete drain surface 94 from three sides, and also allows wheeled vehicles, including bicycles, to ride over the depression created by the drain surface without losing control. Reinforcement studs 28 secure the frame 12 to the paving. The curb hood 22 matches the shape and curvature of the curb within which the one-piece frame and gutter drain is installed.
A second frame style in accordance with the present invention for use with a shoulder berm gutter form, as constructed for concrete contouring, is shown in FIGS. 12A and 12B. As shown by the frame without concrete in FIG. 12A, the bottom 96 of the frame is essentially perpendicular to the side panels 18 , and has a back rear edge 98 adjacent the frame drain opening 84 . On each side of the back rear edge 98 , there preferably is an upwardly extending fin 91 that abuts the respective side panel 18 and slopes downwardly toward the center of the rear edge 98 . The height of the side panels 18 where they abut the front panel is typically somewhat greater than the height of the side panels at the front edge of the curb hood 22 . A plurality of reinforcement rods 92 extend laterally between the side panels 18 . Concrete is poured into the frame and contoured to be level with the top edge of the front panel 16 , sloping downwardly toward the back rear edge 98 , as shown in FIG. 12B; preferably, the slope is approximately 2:1. The concrete, when set into the sloping concrete drain surface 100 , is strengthened by the reinforcement rods 92 . When installed, the top edges of the side panels 18 and front panel 16 are flush with the surrounding paving. This allows water to flow directly into the sloping concrete drain surface 100 from three sides, and also allows wheeled vehicles, including bicycles, to ride over the depression created by the drain surface without losing control. Reinforcement studs 28 secure the frame to the paving. The curb hood 22 matches the shape and curvature of the curb within which the one-piece frame and gutter drain is installed.
A third frame style in accordance with the present invention for use with an “S” style transversible curb and gutter form, as constructed for concrete contouring, is shown in FIGS. 13A and 13B. As shown by the frame 12 without concrete in FIG. 13A, the bottom 120 of the frame includes an upwardly extending rear edge 122 . Near the midpoint between the side panels 18 , the top of the rear edge 122 is approximately parallel to the bottom 120 of the frame and has relatively little vertical height. Moving outward from the midpoint toward each side panel 18 , the rear edge 122 slopes upwardly so that, when the rear edge 122 abuts the side panels 18 , the top of each side of the rear edge 122 is approximately flush with the top edge of the respective side panel 18 . A plurality of reinforcement rods 92 extend laterally between the side panels 18 . Concrete is poured into the frame and contoured to be flush with the top edges of the front panel 16 and side panels 18 , sloping downward toward the middle of the rear edge 122 , as shown in FIG. 13B; preferably, the slope is approximately 2:1. The upwardly sloping sides of the rear edge 122 ensure a downward slope is achieved from the top edge of either side panel 18 toward the middle of the rear edge 122 . The concrete, when set into the contoured concrete drain surface 124 , is strengthened by the reinforcement rods 92 . When installed, the top edges of the side panels 18 and front panel 16 are flush with the surrounding paving. This allows the water to flow directly into the contoured concrete drain surface 124 from three sides, and also allows wheeled vehicles, including bicycles, to ride over the depression created by the drain surface without losing control. Reinforcement studs 28 secure the frame 12 to the paving. The curb hood 22 matches the shape and curvature of the curb within which the onepiece frame and gutter drain is installed.
The three most common curb forms are shown in profile or side view in FIGS. 14A-C. The form in FIG. 14A is a standard 90° 2′6″ curb and gutter form and represents the style of curb within which the frame depicted in FIGS. 10 and 11 A- 11 B is intended to be installed. The form in FIG. 14B is a 36 ″ shoulder berm gutter form and represents the style of curb within which the frame shown in FIGS. 12A-12B is intended to be installed. The form in FIG. 14C is an “S” style transversible curb and gutter form and represents the style of curb within which the frame shown in FIGS. 13A-13B is intended to be installed. Other curb styles are also possible and may be easily accommodated through adjustment in frame construction.
To install the curb and gutter one-piece frame and funnel drain 10 , the desired curb form 60 is installed to the desired elevation. A hole must be dug into the supporting earth 36 at the desired drain location. Then the one-piece frame and funnel drain 10 is mounted directly in the curb form 60 using the dowels 32 , with the funnel drain 14 extending downwardly into the hole in the ground. Once the frame and funnel drain 10 is mounted in the form 60 , the concrete paving 30 can be poured by a standard slip form curb and gutter paver. The frame and funnel drain 10 can be mounted directly in the curb form 60 and “paved over” because the side panels of the frame 12 are the same shape as the cutter plates 64 within the curb form 60 . As a result, curb and gutter installation and drain pipe installation can be done simultaneously instead of in the two steps that are otherwise necessary to complete the open sections of paving in the portion of the curb that contains the frame.
Once the concrete paving sets, the cutter plates 64 are removed and the longitudinal members 62 are pulled outwardly off the dowels 32 . The frame 12 is secured to the set concrete paving 30 by the reinforcement studs 28 . Using funnel attachments, such as elbows 46 , funnel extensions 38 and saddle fittings 44 , the final connection between the funnel drain 14 and the drain pipe 42 can be made then or at a later time.
The foregoing descriptions and drawings should be considered as illustrative only of the principles of the invention. The invention may be constructed in a variety of configurations and is not limited to the configurations shown in the preferred embodiments. Therefore, it is not desired to limit the invention to the specific examples disclosed or the exact construction and operation shown and described. Rather, all suitable modifications and equivalents may be resorted to, falling within the scope of the invention. | A prefabricated one-piece metal frame and funnel drain is constructed for curb and gutter use. The frame may be constructed in a number of styles, with a particular style selected to match the desired curb form. The funnel drain also includes a variety of styles in order to accommodate different drain pipe orientations and configurations. When welded together, the frame and funnel drain may be mounted within any standard curb and gutter form such that curb and gutter installation and drain pipe installation may be accomplished simultaneously, without any preparatory concrete work required for placement of the frame and funnel drain. | 4 |
CROSS REFERENCE TO RELATED APPLICATION
This application is related to copending U.S. application Ser. No. 379,825, filed on even date herewith, which describes a bleaching and laundering composition comprising monoperoxyphthalic acid and/or a water-soluble salt thereof, a peroxygen compound, an activator comprising phthalic anhydride and a chelating agent.
BACKGROUND OF THE INVENTION
This invention relates, in general, to bleaching and laundering compositions and their application to laundering operations. More specifically, this invention relates to bleaching and laundering compositions containing monoperoxyphthalic acid and/or a water-soluble salt thereof in combination with a chelating agent capable of forming a water-soluble metal complex in aqueous solution.
Bleaching compositions which release active oxygen in the laundry solution are extensively described in the prior art and commonly used in laundering operations. In general, such bleaching compositions contain peroxygen compounds, such as, perborates, percarbonates, perphosphates and the like which promote the bleaching activity by forming hydrogen peroxide in aqueous solution. A major drawback attendant to the use of such peroxygen compounds is that they are optimally effective at the relatively low washing temperatures employed in most household washing machines in the United States, i.e., temperatures in the range of 80° to 130° F. By way of comparison, European wash temperatures are generally substantially higher extending over a range, typically, from 90° to 200° F. However, even in Europe and those other countries which generally presently employ near boiling washing temperatures, there is a trend towards lower temperature laundering.
In an effort to enhance the bleaching activity of peroxygen bleaches, the prior art has employed materials called activators in combination with the peroxygen compounds. It is generally believed that the interaction of the peroxygen compound and the activator results in the formation of a peroxyacid which is the active species for bleaching. Numerous compounds have been proposed in the art as activators for peroxygen bleaches among which are included carboxylic acid anhydrides such as those disclosed in U.S. Pat. Nos. 3,928,775; 3,338,839; and 3,352,634; carboxylic esters such as disclosed in U.S. Pat. No. 2,995,905; N-acyl compounds such as those described in U.S. Pat. Nos. 3,912,648 and 3,919,102; cyanomines such as described in U.S. Pat. No. 4,199,466; and acyl sulfoamides such as disclosed in U.S. Pat. No. 3,245,913.
Pre-formed peroxyacids have also been used to effect bleaching in laundry wash solutions. U.S. Pat. Nos. 3,770,816; 4,170,453; and 4,259,201 are illustrative of prior art disclosures relating to bleaching compositions comprising a peroxyacid compound.
It is generally recognized in the art that metal ions are capable of acting as decomposition catalysts for inorganic peroxygen compounds and organic peroxyacids. In an effort to stabilize such bleaching species in the wash solution, chelating agents have been incorporated into bleaching detergent compositions. U.S. Pat. No. 3,243,378 to Stoltz, for example, discloses a bleaching composition containing a peroxygen bleaching compound and a chelating agent to sequester metal cations. In general, the chelating agents which have been used for this purpose fall into one of two categories: (a) materials such as heterocyclics compounds and ketones, notably 8-hydroxyquinoline, which tie up metal cations in the laundry wash by precipitating them from solution; and (b) materials such as aminopolycarboxylates and aminopolyphosphonate compounds which form water-soluble metal complexes with the cations present in the wash solution. Accordingly, U.S. Pat. No. 4,005,029 discloses that selected aldehydes, ketones and compounds which yield aldehydes or ketones in aqueous solution (e.g., 8-hydroxyquinoline) can be used to activate aliphatic peroxyacids, such as, diperazelaic acid, diperadipic acid and aromatic peroxyacids (and water-soluble salts thereof) including monoperoxyphthalic acid and diperoxyterephthalic acid. In U.S. Pat. No. 4,170,453, a mixture of 8-hydroxyquinoline, phosphoric acid and sodium pyrophosphate is disclosed as a preferred chelating system to stabilize the active oxygen generated in wash solutions containing diperoxydodecandioic acid, U.S. Pat. No. 4,225,452 to Leigh discloses the combination of specified classes of chelating agents (among which are phosphonate compounds) with inorganic peroxygen compounds and an organic activator for the purpose of suppressing the decomposition of the peroxygen compound in the bleach composition. Specifically, the chelating agent is said to inhibit the unwanted side reaction of the peroxygen compound with the peroxyacid formed by the primary reaction of the peroxygen compound and the activator, the effect of the side reaction being to deplete the peroxyacid bleaching species from solution. The Leigh patent, however, discourages the use of such chelating agents in solutions wherein the peroxyacid has a double bond between the carbon atoms in the α,α' position to the carbonyl group. Specifically, at column 2 of the patent, beginning at line 63, the patentee excludes phthalic anhydride as an activator for the disclosed bleaching composition because of instability. Inasmuch as the peroxyacid formed by the reaction of phthalic anhydride and an inorganic peroxygen compound is monoperoxyphthalic acid, the Leigh patent apparently discourages the use of monoperoxyphthalic acid in the bleaching compositions of the patent.
European Patent Publication No. 0,027,693, published Apr. 29, 1981, discloses the use of magnesium monoperoxyphthalate as an effective bleaching agent. There is also disclosed the optional combination of a bleaching agent with an "aldehyde or ketone peroxyacid activator as described in U.S. Pat. No. 4,005,029, e.g., 8-hydroxyquinoline which is a known peroxygen stabilizer". The Publication also discloses organic phosphonate compounds, along with a wide variety of other compounds, as being useful detergent builders which optionally may be included in the described washing compositions. No disclosure is made, however, concerning the beneficial effects attendant to the use of a small amount of organic phosphonate compounds to serve as chelating agents in bleaching compositions and particularly, in compositions containing magnesium monoperoxyphthalate.
Thus, while the art has concerned itself with improving the stability of peroxygen and peroxyacid bleaching compounds with the use of chelating agents, it has heretofore failed to disclose or suggest the specific combination of peroxyacid compounds with chelating agents of the type which form substantially water-soluble compounds or complexes with metal cations in the aqueous wash solution, the use of such type chelating agents being solely disclosed in combination with peroxygen compounds used alone or in combination with activators. Moreover, the beneficial effect attendant to the combination of such chelating agents with monoperoxyphthalic acid and/or a water-soluble salt thereof, in particular, is unappreciated in the prior art.
SUMMARY OF THE INVENTION
The present invention provides a bleaching composition comprising monoperoxyphthalic acid (also referred to herein as "MPPA" for purposes of convenience) and/or a water-soluble salt thereof and a chelating agent capable of forming a substantially water-soluble compound or complex with metal ion in aqueous solution.
The bleaching detergent composition of the invention comprises the above-defined bleaching composition in combination with a surface active detergent and one or more detergent builder salts. In accordance with the process of the invention, bleaching of stained and/or soiled materials is effected by contacting such materials with an aqueous solution of the above-defined compositions.
The term "chelating agent" as used herein refers to organic compounds which, in small amounts, are capable of binding transition metal cations, (e.g., iron, nickel and cobalt) which are known to adversely affect the stability of peroxygen compounds and/or peroxyacids in aqueous bleaching solutions. The chelating agents employed herein therefore exclude inorganic compounds ordinarily used in detergent formulations as builder salts. The chelating agents useful for the present invention are of the type capable of forming a substantially water-soluble, rather than a precipitated, metal complex in aqueous solutions with metal ions, most notably, transition metal cations such as those referred to above. Suitable chelating agents therefore include ethylene diamine tetraacetic acid (EDTA); nitrilotriacetic acid (NTA); diethylene triamine pentaacetic acid; ethylene diamine tetramethylene phosphonic acid (EDITEMPA); amino trimethylene phosphonic acid (ATMP); diethylene triamine pentacetic acid (DETPA), all of the above-mentioned compounds being preferably employed in the form of the sodium salt. In contrast thereto, chelating agents, such as, 8-hydroxyquinoline, which form a precipitated metal complex in aqueous solution are excluded from the present invention.
A preferred class of chelating agents are the organic phosphonate compounds such as those disclosed in U.S. Pat. No. 4,225,452, the formulae of which are set forth in Equations I, II and III in columns 3 and 4 of the patent. Among this class of materials diethylene triamine pentamethylene phosphonic acid (referred to herein as "DTPMP"), and/or a water-soluble salt thereof is particularly preferred as a chelating agent for purposes of the present invention. Among the salts of DTPMP, the sodium, potassium and ammonium salts are generally preferred because of their relatively greater solubility and ease of preparation.
In general, the chelating agents employed in the bleaching compositions of the invention are present in a weight ratio relative to MPPA and/or its salts of from about 1:5 to about 1:50, and more preferably, from about 1:7 to about 1:20. In the built bleaching detergent compositions of the invention, the concentration of chelating agent is generally below about 5%, by weight, preferably below about 2%, by weight, and most preferably below about 1%, by weight, of such detergent compositions. The chelating agents may be utilized alone or in combination with one or more other chelating agents. Thus, for example, DTPMP may be advantageously employed in combination with EDTA in the compositions of the invention.
DETAILED DESCRIPTION OF THE INVENTION
Monoperoxyphthalic acid and/or one or more of its water-soluble salts are the primary bleaching agents in the bleaching compositions of the invention. Although MPPA provides acceptable bleaching activity, it has the disadvantage of relatively poor stability when stored in admixture with other components ordinarily present in household detergent compositions. Hence, for purposes of stability, the magnesium salt of MPPA is preferably employed in the compositions of the invention, namely, magnesium monoperoxyphthalate. A preferred bleaching composition thus comprises about 65 wt.% magnesium monoperoxyphthalate, about 11 wt.% magnesium phthalate, and the balance water and a sequestering agent. The active oxygen content of this bleaching composition is about 5 to 6%. The alkali metal, calcium or barium alkaline earth and/or ammonium salts of MPPA may also be employed in the bleaching and laundering compositions of the invention, although such salts are generally less preferred from the standpoint of stability than the aforementioned magnesium salt.
The production of MPPA is generally effected by the reaction of hydrogen peroxide and phthalic anhydride. The resultant MPPA can then be used to produce magnesium monoperoxyphthalate by reaction with a magnesium compound in the presence of an organic solvent. A detailed description of the product of MPPA and its magnesium salt is set forth on pages 7 to 10, inclusive, of European Patent Publication No. 0,027,693, published April 29, 1981, the aforementioned pages 7 to 10 being incorporated herein by reference.
The MPPA bleaching agent (or a salt thereof) may optionally be combined in the present bleaching compositions with a conventional peroxygen bleach compound and an activator therefor. Examples of suitable peroxygen compounds include alkali metal perborates, percarbonates, perphosphates and the like, sodium perborate being particularly preferred because of its commercial availability. Conventional activators such as those disclosed, for example, at column 4 of the U.S. Pat. No. 4,259,200 are suitable for use in conjunction with such peroxygen compound. The polyacylated amines are generally of special interest, TAED in particular being a preferred activator. Other suitable activators include anhydride compounds, such as, benzoic, maleic, succinic and phthalic; and acyl compounds such as N-acetyl and N-benzoyl-imidazoles. The use of MPPA in combination with a peroxygen compound activated with phthalic anhydride is a particularly preferred bleaching composition described in the aforementioned copending U.S. Application Ser. No. 379,825, filed on even date herewith. In general, the molar ratios of peroxygen compound to activator can vary widely depending upon the particular choice of peroxygen compound and activator. However, molar ratios of from about 0.5:1 to about 25:1 are generally suitable for providing satisfactory bleaching performance.
In accordance with another embodiment of the invention, the bleaching agent employed in the bleaching composition described herein is devoid of a peroxygen compound and is solely comprised of MPPA and/or its water-soluble salts. In general, such bleaching compositions are most effective at the relatively low washing temperatures employed in typical household washing machines in the United States.
The amount of bleaching composition added to the wash solution is generally selected to provide an amount of peroxyacid compound within the range corresponding to about 3 to 100 parts of active oxygen per million parts of the wash solution.
MPPA and/or its water-soluble salt in combination with a chelating agent may be formulated as a separate bleach product, or alternatively may be employed in a built detergent composition. Accordingly, the bleaching composition of the invention may include conventional additives used in the fabric washing art, such as, binders, fillers, builder salts, proteolytic enzymes, optical brighteners, perfumes, dyes, corrosion inhibitors, anti-redeposition agents, foam stabilizers and the like, all of which may be added in varying quantities depending on the desired properties of the bleaching composition and their compatability with such composition. Additionally, the bleaching compositions of the invention may be incorporated into laundering detergent compositions containing one or more surface active agents selected from the group consisting of anionic, cationic, nonionic, ampholytic and zwitterionic detergents.
When the instant bleaching compositions are incorporated into a conventional laundering composition and are thus provided as a fully formulated bleaching detergent composition, the latter compositions will comprise the following: from about 5 to 50%, by weight, of the instant bleaching composition; from about 5 to 50%, by weight, of a detergent surface active agent, preferably from about 5 to 30% by weight; and from about 5 to 80%, by weight, of a detergent builder salt which can also function as a buffer to provide the requisite pH range when the laundering composition is added to water. The aqueous wash solutions will have a pH range of from about 7 to 12, preferably from about 8 to 10, and most preferably from about 8.5 to 9. A preferred amount of the builder salt is from about 20% to about 65%, by weight of the composition. The balance of the composition will predominantly comprise water, filler salts, such as, sodium sulfate, and optionally, minor additives, such as, optical brighteners, perfumes, dyes, anti-redeposition agents and the like.
Among the anionic surface active agents useful in the present invention are those surface active or detergent compounds which contain an organic hydrophobic group containing generally from about 8 to 26 carbon atoms and preferably 10 to 18 carbon atoms in their molecular structure and at least one water-solubilizing group selected from the groups of sulfonate, sulfate, carboxylate, phosphonate and phosphate so as to form a water-soluble detergent.
Examples of suitable anionic detergents include soaps, such as, the water-soluble salts (e.g., the sodium, potassium, ammonium and alkanolammonium salts) of higher fatty acids or resin salts containing from about 8 to 20 carbon atoms and preferably 10 to 18 carbon atoms. Suitable fatty acids can be obtained from oils and waxes of animal or vegetable origin, for example, tallow, grease, coconut oil and mixtures thereof. Particularly useful are the sodium and potassium salts of the fatty acid mixtures derived from coconut oil and tallow, for example, sodium coconut soap and potassium tallow soap.
The anionic class of detergents also includes the water-soluble sulfated and sulfonated detergents having an alkyl radical containing from about 8 to 26, and preferably from about 12 to 22 carbon atoms. Examples of the sulfonated anionic detergents are the higher alkyl mononuclear aromatic sulfonates such as the higher alkyl benzene sulfonates containing from about 10 to 16 carbon atoms in the higher alkyl group in a straight or branched chain, such as, for example, the sodium, potassium and ammonium salts of higher alkyl benzene sulfonates, higher alkyl toluene sulfonates and higher alkyl phenol sulfonates.
Other suitable anionic detergents are the olefin sulfonates including long chain alkene sulfonates, long chain hydroxyalkane sulfonates or mixtures of alkene sulfonates and hydroxyalkane sulfonates. The olefin sulfonate detergents may be prepared in a conventional manner by the reaction of SO 3 with long chain olefins containing from about 8 to 25, and preferably from about 12 to 21 carbon atoms, such olefins having the formula RCH═CHR 1 wherein R is a higher alkyl group of 6 to 23 carbons and R 1 is an alkyl group containing from about 1 to 17 carbon atoms or hydrogen to form a mixture of sultones and alkene sulfonic acids which is then treated to convert the sultones to sulfonates. Other examples of sulfate or sulfonate detergents are paraffin sulfonates containing from about 10 to 20 carbon atoms, and preferably from about 15 to 20 carbon atoms. The primary paraffin sulfonates are made by reacting long chain alpha olefins and bisulfites. Paraffin sulfonates having the sulfonate group distributed along the paraffin chain are shown in U.S. Pat. Nos. 2,503,280; 2,507,088; 3,260,741; 3,372,188 and German Pat. No. 735,096. Other useful sulfate and sulfonate detergents include sodium and potassium sulfates of higher alcohols containing from about 8 to 18 carbon atoms, such as, for example, sodium lauryl sulfate and sodium tallow alcohol sulfate, sodium and potassium salts of alpha-sulfofatty acid esters containing about 10 to 20 carbon atoms in the acyl group, for example, methyl alpha-sulfomyristate and methyl alphasulfotallowate, ammonium sulfates of mono- or di-glycerides of higher (C 10 -C 18 ) fatty acids, for example, stearic monoglyceride monosulfate; sodium and alkylol ammonium salts of alkyl polyethenoxy ether sulfates produced by condensing 1 to 5 moles of ethylene oxide with 1 mole of higher (C 8 -C 18 ) alcohol; sodium higher alkyl (C 10 -C 18 ) glyceryl ether sulfonates; and sodium or potassium alkyl phenol polyethenoxy ether sulfates with about 1 to 6 oxyethylene groups per molecule and in which the alkyl radicals contain about 8 to 12 atoms.
The most highly preferred water-soluble anionic detergent compounds are the ammonium and substituted ammonium (such as mono, di and tri-ethanolamine), alkali metal (such as, sodium and potassium) and alkaline earth metal (such as, calcium and magnesium) salts of the higher alkyl benzene sulfonates, olefin sulfonates and higher alkyl sulfates. Among the above-listed anionics, the most preferred are the sodium linear alkyl benzene sulfonates (LABS).
The nonionic synthetic organic detergents are characterized by the presence of an organic hydrophobic group and an organic hydrophilic group and are typically produced by the condensation of an organic alphatic or alkyl aromatic hydrophobic compound with ethylene oxide (hydrophilic in nature). Practically any hydrophobic compound having a carboxy, hydroxy, amido or amino group with a free hydrogen attached to the nitrogen can be condensed with ethylene oxide or with the polyhydration product thereof, polyethylene glycol, to form a nonionic detergent. The length of the hydrophilic or polyoxyethylene chain can be readily adjusted to achieve the desired balance between the hydrophobic and hydrophilic groups.
The nonionic detergents include the polyethylene oxide condensate of 1 mole of alkyl phenol containing from about 6 to 12 carbon atoms in a straight or branched chain configuration with about 5 to 30 moles of ethylene oxide, for example, nonyl phenol condensed with 9 moles of ethylene oxide; dodecyl phenol condensed with 15 moles of ethylene oxide; and dinonyl phenol condensed with 15 moles of ethylene oxide. Condensation products of the corresponding alkyl thiophenols with 5 to 30 moles of ethylene oxide are also suitable.
Of the above-described types of nonionic surfactants, those of the ethoxylated alcohol type are preferred. Particularly preferred nonionic surfactants include the condensation product of coconut fatty alcohol with about 6 moles of ethylene oxide per mole of coconut fatty alcohol, the condensation product of tallow fatty alcohol with about 11 moles of ethylene oxide per mole of tallow fatty alcohol, the condensation product of a secondary fatty alcohol containing about 11-15 carbon atoms with about 9 moles of ethylene oxide per mole of fatty alcohol and condensation products of more or less branched primary alcohols, whose branching is predominantly 2-methyl, with from about 4 to 12 moles of ethylene oxide.
Zwitterionic detergents such as the betaines and sulfobetaines having the following formula are also useful: ##STR1## wherein R is an alkyl group containing from about 8 to 18 carbon atoms, R 2 and R 3 are each an alkylene or hydroxyalkylene group containing about 1 to 4 carbon atoms, R 4 is an alkylene or hydroxyalkylene group containing 1 to 4 carbon atoms, and X is C or S:O. The alkyl group can contain one or more intermediate linkages such as amido, ether, or polyether linkages or nonfunctional substituents such as hydroxyl or halogen which do not substantially affect the hydrophobic character of the group. When X is C, the detergent is called a betaine; and when X is S:O, the detergent is called a sulfobetaine or sultaine.
Cationic surface active agents may also be employed. They comprise surface active detergent compounds which contain an organic hydrophobic group which forms part of a cation when the compound is dissolved in water, and an anionic group. Typical cationic surface active agents are amine and quaternary ammonium compounds.
Examples of suitable synthetic cationic detergents include: normal primary amines of the formula RNH 2 wherein R is an alkyl group containing from about 12 to 15 atoms; diamines having the formula RNHC 2 H 4 NH 2 wherein R is an alkyl group containing from about 12 to 22 carbon atoms, such as N-2-aminoethyl-stearyl amine and N-2-aminoethyl myristyl amine; amide-linked amines, such as those having the formula R 1 CONHC 2 H 4 NH 2 wherein R 1 is an alkyl group containing about 8 to 20 carbon atoms, such as N-2-amino ethylstearyl amide and N-amino ethylmyristyl amide; quaternary ammonium compounds wherein typically one of the groups linked to the nitrogen atom is an alkyl group containing about 8 to 22 carbon atoms and three of the groups linked to the nitrogen atom are alkyl groups which contain 1 to 3 carbon atoms, including alkyl groups bearing inert substituents, such as phenyl groups, and there is present an anion such as halogen, acetate, methosulfate, etc. The alkyl group may contain intermediate linkages such as amide which do not substantially affect the hydrophobic character of the group, for example, stearyl amido propyl quaternary ammonium chloride. Typical quaternary ammonium detergents are ethyl-dimethyl-stearyl-ammonium chloride, benzyl-dimethyl-stearyl ammonium chloride, trimethyl-stearyl ammonium chloride, trimethyl-cetyl ammonium bromide, dimethylethyl-lauryl ammonium chloride, dimethyl-propyl-myristyl ammonium chloride, and the corresponding methosulfates and acetates.
Ampholytic detergents are also suitable for the invention. Ampholytic detergents are well known in the art and many operable detergents of this class are disclosed by A. M. Schwartz, J. W. Perry and J. Birch in "Surface Active Agents and Detergents," Interscience Publishers, New York, 1958, vol. 2. Examples of suitable amphoteric detergents include: alkyl betaiminodipropionates, RN(C 2 H 4 COOM) 2 ; alkyl beta-amino propionates, RN(H)C 2 H 4 COOM; and long chain imidazole derivatives having the general formula: ##STR2## wherein in each of the above formulae R is an acyclic hydrophobic group containing from about 8 to 18 carbon atoms and M is a cation to neutralize the charge of the anion. Specific operable amphoteric detergents include the disodium salt of undecylcycloimidiniumethoxyethionic acid-2-ethionic acid, dodecyl beta alanine, and the inner salt of 2-trimethylamino lauric acid.
The laundry detergent composition of the invention optionally contain a detergent builder of the type commonly used in detergent formulations. Useful builders include any of the conventional inorganic water-soluble builder salts, such as, for example, water-soluble salts of phosphates, pyrophosphates, orthophosphates, polyphosphates, silicates, carbonates, and the like. Organic builders include water-soluble phosphonates, polyphosphonates, polyhydroxysulfonates, polyacetates, carboxylates, polycarboxylates, succinates and the like.
Specific examples of inorganic phosphate builders include sodium and potassium tripolyphosphates, pyrophosphates and hexametaphosphates. The organic polyphosphonates specifically include, for example, the sodium and potassium salts of ethane 1-hydroxy-1, 1-diphosphonic acid and the sodium and potassium salts of ethane-1, 1, 2-triphosphonic acid. Examples of these and other phosphorous builder compounds are disclosed in U.S. Pat. Nos. 3,213,030; 3,422,021; 3,422,137 and 3,400,176. Pentasodium tripolyphosphate and tetrasodium pyrophosphate are especially preferred water-soluble inorganic builders.
Specific examples of non-phosphorous inorganic builders include water-soluble inorganic carbonate, bicarbonate and silicate salts. The alkali metal, for example, sodium and potassium, carbonates, bicarbonates and silicates are particularly useful herein.
Water-soluble organic builders are also useful. For example, the alkali metal, ammonium and substituted ammonium polyacetates, carboxylates, polycarboxylates and polyhydroxysulfonates are useful builders for the compositions and processes of the invention. Specific examples of polyacetate and polycarboxylate builders include sodium, potassium, lithium, ammonium and substituted ammonium salts of ethylene diaminetetracetic acid, nitrilotriacetic acid, benzene polycarboxylic (i.e. penta- and tetra-) acids, carboxymethoxysuccinic acid and citric acid.
Water-insoluble builders may also be used, particularly, the complex silicates and more particularly, the complex sodium alumino silicates such as, zeolites, e.g., zeolite 4 A, a type of zeolite molecule wherein the univalent cation is sodium and the pore size is about 4 Angstroms. The preparation of such type zeolite is described in U.S. Pat. No. 3,114,603. The zeolites may be amorphous or crystalline and have water of hydration as known in the art.
An inert, water-soluble filler salt is desirably included in the laundering compositions of the invention. A preferred filler salt is an alkali metal sulfate, such as, potassium or sodium sulfate, the latter being especially preferred.
Various adjuvants may be included in the bleaching detergent compositions of the invention. For example, colorants, e.g., pigments and dyes, anti-redeposition agents, such as, carboxymethylcellulose, optical brighteners, such as, anionic, cationic, or nonionic brighteners; foam stabilizers, such as, alkanolamides, proteolytic enzymes and the like are all well-known in the fabric washing art for use in detergent compositions.
The bleaching compositions of the invention are prepared by admixing the ingredients as hereinafter illustrated. When preparing laundering compositions containing the bleaching composition in combination with a surface active detergent compound and/or builder salts, MPPA and/or a salt thereof and the chelating agent of choice can be mixed either directly with the detergent compound, builder and the like, or the MPPA and/or its salt can be coated with a coating material to prevent premature activation of the bleaching agent. The coating process is conducted in accordance with procedures well known in the art. Suitable coating materials include compounds such as magnesium sulfate, polyvinyl alcohol, lauric acid or its salts and the like.
EXAMPLE 1
A preferred low temperature bleach product has the following composition:
______________________________________Component Weight Percent______________________________________Sodium linear C.sub.10 -C.sub.13 alkyl 5benzene sulfonate.Ethoxylated C.sub.11 -C.sub.18 alcohol 3(11 moles of EO per mole alcohol)Soap (sodium salt of C.sub.12 -C.sub.22 5carboxylic acids)Sodium silicate (1 Na.sub.2 O:2 SiO.sub.2) 3Pentasodium tripolyphosphate (TPP) 40Sodium salt of diethylene triamine 0.5pentamethylene phosphonic acid (DTPMP)Enzyme.sup.a 0.4Optical brighteners 0.2H-48.sup.b 7.0Perfume 0.18Sodium sulfate 22Water q.s.______________________________________ .sup.a A proteolytic enzyme purchased as Alcalase 2M (2 anson units/gram) or as Maxatase P. .sup.b A bleaching composition sold by Interox Chemicals Limited London, England, containing about 65 wt. % magnesium monoperoxyphthalate, 11 wt. magnesium phthalate, balance H.sub.2 O.
The foregoing product is produced by spray drying an aqueous slurry containing 60%, by weight of a mixture containing all of the above components except the enzyme, perfume and H-48 bleaching composition. The resultant spray dried product has a particle size in the range of 8 mesh to 150 mesh, (U.S. Sieve Series) and a moisture content of about 14%. 92.5 parts by weight of said spray dried product are mixed with 7 parts by weight of H-48 of similar mesh size, 0.3 parts by weight of enzyme and 0.18 parts by weight of perfume in a rotary drum to yield a particulate product of the foregoing composition having a moisture of approximately 13%, by weight.
The above described product is used to wash soiled fabrics in a washing machine, and good laundering and bleaching performance is obtained.
Other satisfactory products can be obtained by varying the concentrations of the following principal components in the above-described composition as follows:
______________________________________Component Weight Percent______________________________________Alkyl benzene sulfonate 4-12Ethoxylated alcohol 1-6Soap 1-10TPP or alternative builder 15-50Enzyme 0.1-2H-48 1-20DTPMP 0.1-5______________________________________
For highly concentrated heavy duty detergent powders, the alkyl benzene sulfonate and soap components in the above-described composition may be deleted, and the ethoxylated alcohol and TPP components may be increased to an upper limit of 20 and 75 weight percent, respectively.
EXAMPLE 2
Test Procedure
Bleaching tests were carried out on standard stained test swatches (described below) using the various bleaching and laundering compositions described in table 1 of this Example in a Tergotometer vessel manufactured by the U.S. Testing Company. The Tergotometer was maintained at a constant temperature of 120° F. and operated at 100 rpm.
Each of the test compositions described in Table 1 below was added to one liter of tap water at 120° F. having a water hardness of about 100 ppm, as calcium carbonate. The test compositions were agitated for about one minute and then a mixed fabric laod consisting of two swatches each (3"×4") of the stained fabrics described below was added to each wash receptacle. After a 15 minute wash at 120° F., the test fabrics were rinsed in 100° F. tap water and then dried. The percent stain removal was measured by taking a reflectance reading for each stained test swatch prior to and after the washing using a Gardner Color Difference Meter, and the percent stain removal (% S.R.) was calculated as follows: ##EQU1## wherein "Rd before washing" represents the Rd value after staining.
The value of percent stain removal calculated for all five cloths were averaged for each test laundering composition. A difference greater than 2% in the average of the five stained cloths tested is considered significant.
At the end of each wash, the active oxygen content of the wash solution was determined by acidification with dilute sulfuric acid followed by treatment of the wash solution with potassium iodide and a minor amount of ammonium molybdate, and thereafter titration with standardized sodium thiosulfate using starch as the indicator.
The respective stains and test swatches were as follows:
______________________________________Stain Test Cloth______________________________________1. Grape 65 Dacron - 35 Cotton2. Blueberry Cotton3. Sulfo Dye EMPA 115 (Cotton)4. Red Wine EMPA 114 (Cotton)5. Coffee/Tea Cotton______________________________________
Stained test cloths 1 and 2 are prepared by passing rolls of unsoiled fabric through a padding and drying apparatus (manufactured by Benz of Zurich, Switzerland) containing either grape or blueberry solutions at 90° F. After drying at 250° F., the fabric is cut into 3"×4" swatches. Eighty of these swatches, impregnated with the same stain, are rinsed in 17 gallons of 85° F. water in an automatic home washer. They are then dried by a passage through a Beseler Print Dryer at a machine temperature setting of 6 and a speed of 10.
Stained fabrics 3 and 4 are purchased from Testfabrics Incorporated of Middlesex, N.J., and cut into 3"×4" swatches.
Stained fabric 5 is prepared by agitating and soaking unsoiled cotton strips (18"×36") in a washing machine filled with a solution of coffee/tea (8:1 weight ratio) at 150° F. The machine is allowed to rinse-spin dry to remove the coffee/tea solution. The stained fabric is then machine washed twice with hot pyrophosphate-surfactant solution followed by two complete water wash cycles at 140° F. The strips are then dried by two passes through an Ironrite machine set at 10 and then cut into 3"×4" swatches.
A granular detergent composition (designated herein as "HDD") was prepared by conventional spray-drying and had the following approximate composition:
______________________________________Composition Weight Percent______________________________________Sodium tridecylbenzenesulfonate 15Ethoxylated C.sub.12 -C.sub.15 1primary alcohol (7 molesEO/mole alcohol)Sodium tripolyphosphate 33Sodium carbonate 5Sodium silicate 7Sodium carboxymethylcellulose 0.5Optical brighteners 0.2Perfume 0.2Water 11Sodium sulfate balance______________________________________
Detergent compositions A-E containing HDD were formulated as set forth in Table 1.
TABLE 1______________________________________ CompositionComponent A B C D E______________________________________Detergent, HDD 4.50 g 4.50 g 4.50 g 4.50 g 4.50 gH-48.sup.1 -- 0.49 0.49 0.49 0.49DTPMP.sup.2 -- -- 0.09 -- --EDTA.sup.3 -- -- -- 0.09 --NTA.sup.4 -- -- -- -- 0.18______________________________________ .sup.1 A bleaching composition containing monoperoxyphthalic acid (as magnesium salt) obtained from Interox Chemicals Houston, Texas and having an active oxygen content of 5.1%. .sup.2 Sodium diethylene triamine pentamethylene phosphonate obtained fro P. A. Hunt Chemical Corp., Lincoln, Rhode Island. .sup.3 Ethylene diamine tetraacetic acid, disodium salt. .sup.4 Nitrilotriacetic acid, trisodium salt.
Compositions A through E were tested in accordance with the procedure described above and the results of the bleaching tests are tabulated in Table 2 which sets forth the initial and final values of the active oxygen (A.O.) in the wash solution (expressed as "initial grams" and "residual grams", respectively) and the stain removal achieved for each of the 5 stains.
TABLE 2______________________________________Comparative Bleaching Performance Composition A B C D E______________________________________Initial grams -- 25.0 25.0 25.0 25.0(A.O. × 10.sup.3)Residual grams -- 15.9 18.6 18.5 15.6(A.O. × 10.sup.3)Grams consumed -- 9.1 6.4 6.5 9.4(A.O. × 10.sup.3)Stain removal: % % % % %______________________________________Grape 47 69 72 74 72Blueberry 44 65 68 66 67Sulfodye (EMPA 115) 3 3 3 3 4Red wine (EMPA 114) 38 49 51 44 45Coffee/Tea 17 43 39 38 41Avg. (%) 30 46 47 45 46______________________________________
The results of Table 2 indicate that compositions C and D (containing chelating agents DTPMP and EDTA respectively) consume less active oxygen while providing about an equivalent level of stain removal relative to composition E containing NTA or composition B which contains no chelating agent. | An improved bleaching and laundering composition is provided comprising monoperoxyphthalic acid and/or a water-soluble salt thereof and a chelating agent capable of forming a substantially water-soluble complex with metal ion in aqueous solution. A method of bleaching and laundering soiled and/or stained materials with the aforesaid bleaching composition is also described. A preferred chelating agent is diethylene triamine pentamethylene phosphonic acid (DTPMP) and/or a water-soluble salt thereof. | 2 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a needle thread control device for handling needle threads by taking up and supplying needle threads between thread guides, in a sewing machine, or particularly an overedge sewing machine used for forming stitches of stitch types 503, 504, 514, 516 specified in Federal Standard No. 751a.
2. Prior Art
In the type of overedge sewing machine discussed above, generally, a needle thread handling means is disposed on the path for leading the needle threads from the thread supply source to the sewing needles, and the looseness of the needle threads is absorbed when the needles go up, and the stitches are tightened and the needle threads are pulled off from the needle thread supply source, while the threads are tightened while the needles descend so as to compensate the threads necessary for forming needle thread loops.
However, in the case of, for example, double chain stitches (stitch type 401) which is a part of stitch type 516, when the needle falls into the triangle formed by the looper, the needle thread loop captured by the looper, and the looper thread, if the thread is too loose, the needle thread loop captured by the looper may be tilted or deviated, and the necessary triangle may not be formed. As a result, the needle may hook the needle thread loop or pass over the outside of the triangle to cause thread breakage or skipping of stitches. To solve these problems, it is proposed in Japanese Patent Publication No. 55-43797 to dispose clamp means between the needle thread handling means mounted on the needle bar and the thread guide mounted on the sewing machine main body, to prevent slackening of the needle threads by clamping the needle threads within the clamp means and varying the elevation of the needle thread handling means until the needles fall into the triangle. In Japanese laid-open Utility Model No. 60-188581 it is proposed to install a first thread control cam on the needle bar and the second thread control cam in the lever on which the cloth cutting knife is mounted, so as to absorb the looseness of the thread caused by the descending action of the needle and the action of both thread control cams on the needle threads until the needles fall into the triangle.
Nevertheless, since the needle thread handling means and the thread control cams cannot be placed into the sewing machine frame in an enclosed structure, such means cannot be placed on the needle bar mechanism of a high speed overedge sewing machine having an enclosed frame and lubricated needle bar mechanism in the frame.
Meanwhile, when the draw of the needle thread is short, the stitches are taut, and the soft touch is lost. Such problem occurs not only in the double chain stitches but also in overedge stitches. Therefore, in the overedge sewing machine, generally, the mounting position of the needle guide is adjustable and the position where stitches of soft touch are formed for typical cloth and thread is regarded as the reference position, and the mounting position is adjusted depending on the kind of cloth and thread, and the thread draw is adjusted by the needle thread handling means. When the mounting position is adjusted, the thread draw amount and the thread handling amount by the needle thread handling means will vary significantly, which makes it difficult to obtain stitches of desired touch and look. Furthermore, the reference position was conventionally based on the throat plate or front face of the sewing machine, and placed at the distance from that position to the eyelet of the thread guide, and accordingly, the placement was not easy, because the measurement of the distance was essential to the placement.
SUMMARY OF THE INVENTION
It is hence a primary object of the invention to present a needle thread feed regulating device to be utilized in a high speed industrial overedge sewing machine for forming safety stitches composed of double chain stitches and overedge stitch, which is designed to act on the needle threads so as to prevent them from loosening until the needle for double chain stitches falls into the triangle formed by the looper for double chain stitches, needle thread loop captured by the looper, and looper thread.
It is another object to present a needle thread control device having a simplified structure by forming plural acting parts on one thread control cam, in an overedge sewing machine for forming safety stitches or in an overedge sewing machine having a plurality of needles.
It is still another object of the invention to present a needle thread control device having a simple structure which is capable of easily adjusting the thread pull-off and take-up according to the kind of cloth and thread and is also easily placed in the reference position.
It is a further object to present a needle thread control device capable of producing stitches of fine touch and look and yet is small in the change of thread handling amount if the thread pull-off amount is varied.
It is still another object of the invention to present a needle thread control device equipped with a thread handling area capable of adjusting the thread draw amount without influencing the needle thread control.
In a preferred embodiment, the needle thread feed regulating device of this invention, of which the needle bar mechanism is lubricated in an enclosed chamber of the sewing machine frame, is installed between a thread tension device and the needles in a high speed overedge sewing machine for forming safety stitches composed of double chain stitches and overedge stitches. This needle thread feed regulating device comprises thread guide means having a pair of eyelets disposed at a proper distance in the arm or head part of the sewing machine, and oscillating thread guide means having a cam plate which engages with the needle thread applied between the eyelets and is capable of moving up and down as it is detachably fixed to a knife lever which oscillates in cooperation with the needle bar mechanism outside the enclosed compartment. The cam plate is composed of a first cam part which acts on the needle thread for double chain stitches and a second cam part which acts on the needle for edge looping stitches, and specifically the first cam part acts on the needle thread until the needle for double chain stitches falls into the triangle formed by the looper for double chain stitches the needle thread loop captured by the looper, and the looper thread, thereby absorbing the looseness of the needle thread loop caused by the descending motion of the needle. The structure is simplified because the thread handling of the needle thread for the double chain stitches and the thread handling for the needle thread for overedge stitches are conducted by a common cam plate.
The thread guide means can be adjusted in position so that the eyelet through which the needle thread is passed can move approximately along with the oscillation locus of the cam part formed in the plate of the oscillating thread guide means. The thread guide means and oscillating thread guide means respectively have their reference portions matched when placed at their reference positions. The reference portions are, for example, lines and steps formed in part of the contour of both thread guide means or in both thread guide the means, and these reference portions are preferably identified with a dot, circle mark, triangle mark, arrow or coloring as a guideline for matching so that the reference portions can be distinguished easily.
On the arm or head of the sewing machine, the first thread guide is provided so as to be adjustable in position in the vertical direction on the thread path from the needle thread control device to the needle, while the second thread guide is provided on the needle bar. By positioning the first thread guide so that the second thread guide may be positioned above the first guide area when the needle is at the top dead center, the needle thread is not pulled off by the descending motion of the needle until the level of the second thread guide is even with the first thread handling area, so that the pull-off amount becomes small. Therefore, by moving the first thread guide vertically, the thread pull-off amount can be adjusted without affecting the action of the needle thread feed regulating device.
In a different embodiment, the same needle thread feed regulating device may be similarly installed in an overedge sewing machine having needles.
Many other features, advantages and additional objects of the present invention will become manifest to those versed in the art upon making reference to the detailed description which follows and the accompanying sheets of drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side view of an overedge sewing machine of Federal Standard stitch type 516 for forming safety stitches composed of overedge stitches and double chain stitches;
FIG. 2 is a front view of essential part of the sewing machine shown in FIG. 1 provided with a needle thread feed regulating device;
FIG. 3 and FIG. 4 are magnified side views of the oscillating thread guide of the needle thread feed regulating device at the top dead center and at a position slightly lower than the top dead center;
FIG. 5 and FIG. 6 are drawings showing the placement of the thread guide for double chain stitches and the thread guide for overedge stitches at respective reference positions A, B and B, C.
FIG. 7 is a front view of an overedge sewing machine for forming overedge stitches of stitch type 514;
FIG. 8 is a magnified side view of the needle thread feed regulating device shown in FIG. 7, showing the positioning of the thread guide at the reference positions D and E.
FIG. 9 is a drawing showing the relation between the eyelet and the trajectory of the cam part of the oscillating thread guide when the thread guide is adjusted;
FIG. 10 is a magnified side view of a needle thread feed regulating device used in an overedge sewing machine of stitch type 503, showing the positioning of the thread guide at the reference position;
FIG. 11 is a drawing showing the relation between the eyelet and the locus of the cam part when the thread guide is adjusted in the position in the needle thread feed regulating device shown in FIG. 10; and
FIG. 12 is a magnified side view of the needle thread feed regulating device used in an overedge sewing machine of stitch type 503, 504, showing the positioning of the thread guide at the reference position.
FIG. 13 is an exploded perspective view of the needle thread feed regulating device shown in FIG. 2.
FIG. 14 is a drawing showing the triangle formed by the looper for double chain stitches, the needle thread for forming double chain stitches and the looper thread.
DESCRIPTION OF THE PREFERRED EMBODIMENT
In an overedge sewing machine shown in FIG. 1, an arm 11a of a sewing machine 11 is composed of a sealed chamber and a needle bar 12, projecting downward from the arm 11a and supported movably in the vertical direction, is coupled with a needle bar mechanism (not shown) within the arm 11a, and is designed to move vertically by cooperating with the main shaft while being lubricated, and, at its lower end, there is a needle 13 for overedge stitches and a needle 14 for double chain stiches and in collaboration with a looper for overedge stitches and a looper for double chain stitches (both not shown), overedge and double chain stitches are formed simultaneously.
The sewing machine 11, as does an ordinary overedge sewing machine, possesses a cutter device for cutting and aligning the cloth edges prior to formation of overedge stitches. The cutter device is composed of a lower knife (not shown) fixed beneath a cloth support plate 11b and an upper knife 16 mounted on an oscillating lever 15, and the oscillating lever 15 is affixed to the end of a shaft 19 which projects outwardly from an enclosed frame of the machine 11 and oscillates vertically in cooperation with the main shaft.
A needle thread feed regulating device 21 comprises, as shown in FIG. 2 to FIG. 6, upper thread guides 23 for guiding the needle thread 22 for overedge stitches supported on the arm 11a of the sewing machine, a u-shaped lower thread guide 24 for guiding the needle thread 25 for double chain stitches and an oscillating thread guide 26 connected to the middle part of the oscillating lever 15 by screws 66, and these components are sequentially described below.
A pair of upper thread guides 23 are affixed at a proper distance on a projecting portion of a pin 29 contained in a bracket 28 in a manner so as to both turn and be fixed, and by varying the mounting angle of the pin 29, secured by a screw 30 (see FIG. 2) to the bracket 28, the mounting position of the thread guides 23 can be adjusted, and a pair of spaced eyelets 31 for passing needle thread 22 are provided at the lower ends of each thread guide 23. The bracket 28 for supporting the thread guides 23 is fastened by a setscrew 34 to a bracket 33 which is affixed to the arm 11a by setscrews 32. Thus, the bracket 28 is supported on the arm 11a of the sewing machine through the bracket 33.
The U-shaped lower thread guide 24, like the thread guides 23, is mounted on the bracket 33 so, that the mounting position can be adjusted by screw 30a acting on pin 29a and there is a pair of spaced eyelets 36 for passing the needle thread 25 at each end of the U-bent portion at the end.
The oscillating thread guide 26 possesses a cam part 38 acting on the needle thread 22 for overedge stitches when forming short stitches with a stitching pitch of not less than 8 stitches per inch, an eyelet 39 through which the needle thread 22 is passed when forming long stitches of less than 8 stitches per inch, and a cam plate 26a forming a cam part 40 acting on the needle thread 25 for double chain stitches, and by oscillating around the shaft 19 and moving up and down between the thread guides 23 and 24, take-up and pull-off and compensation of thread supply of the needle threads 22 and 25 are individually carried out between the cam part 38 (or eyelet 39) and eyelets 31 and between the cam part 40 and eyelets 36. Either the cam part 38 or the eyelet 39 is used depending on the length of the stitches of the overedge stitches, while the other is not used. The cam part 40 is composed of two actuating portions 40a, 40b, and the actuating portion 40a draws out the needle thread 25 for double chain stitches first from the needle thread supply source as the oscillating thread guide 26 moves downward from the position shown in FIG. 3 to the position shown in FIG. 4 along with the descending motion of the needle bar 12, and then acts to absorb the looseness of the needle thread 25 caused by the descending motion of the needle 14 until the needle 14 falls into the triangle T formed by the looper for double chain stitches, the loop of the needle thread 25 hooked on this looper L, and the looper thread LT as shown in FIG. 14. Afterwards, the needle thread 25 is further held by the actuating portion until the oscillating thread guide 26 reaches the bottom dead center.
Both thread guides 23 and 24 can be adjusted in the mounting position as stated above, and when the mounting position is changed, the draw amount and thread handling amount of the needle threads 22 and 25 by the cam parts 38 and 40 of the oscillating thread guide 26 vary, but they can be adjusted by determining the position where the optimum stitch for the typical cloth and thread is formed as the reference position, and varying the mounting angle on the basis of this position according to the kind of the cloth and thread.
In order to determine the reference position, the both thread guides 23 and 24 and the cam plate 26a have their own reference contour parts, and when settling on a reference position, it can be fixed by matching these contour parts, and the complicated work of measuring the distance from the front face of the arm of the sewing machine by means of a measure may be omitted. That is, when forming short overedge looping stitches by one needle and two threads, at the bottom dead center of the oscillating thread guide 26, the thread guides 23 are turned around the pin 29 and fixed so that the contour of the upper thread guides 23 in part A shown in FIG. 5 and the contour of the cam plate 26a of the oscillating thread guide 26 may conform to each other.
In the case of overedge stitches of long stitches, as shown in FIG. 6, the contours of the thread guides 23 and the cam plate 26a are matched at the portion C. In this case, by loosening the setscrew 34 and moving the mounting position of the bracket 28 upward, the thread guides 23 are turned around the pin 29.
Concerning the double chain stitches, the thread guide 24 is mounted so that the contours of the lower thread guide 24 and the cam plate 26a are matched at the portion B.
In each thread guide, when the mounting position is changed by turning about the pin as mentioned above, the draw amount and thread handling amount of the needle thread may vary, but their adjustment is not limited to the amount mentioned above. For example, each thread guide may be slidably mounted on the arm of sewing machine to adjust the position along the chord of the arc locus of the oscillating thread guide 26, or it may be rotatably mounted on the shaft on which the oscillating lever is mounted. When the above-mentioned thread guide 24 is adjusted in position along the arc locus of the oscillating thread guide, or when the thread guide in adjusted in position along the chord of the arc locus of the oscillating thread guide, the deviation of the locus of the eyelet by the adjustment of thread guide and the locus of the cam part of the oscillating thread guide may be reduced, and in the latter case, in particular, the deviation of the two can be eliminated, so that the draw amount of the thread can be varied according to the kind of cloth and thread, without varying the thread handling action. This reason is explained in detail in the embodiments shown below.
When placing the thread guide at the reference position, too, aside from the method of matching the contours of both thread guides, for example, one thread guide may be provided with a line or step, and the contour of the other thread guide may be matched to it. Anyway, it is desired to mark the reference portions with a dot, circle, triangle, arrow, or color so as to be distinguished easily.
To the arm 11a of the sewing machine 11 also, as shown in FIG. 2, a thread guide 42 for overedge stitches and a thread guide 43 for double chain stitches are secured by means of setscrews 44 on the needle thread path leading from the needle thread feed regulating device 21 to the needles 13, 14, and the thread guide 43 is designed to be adjusted in position vertically within a range defined by slot 45. By adjusting the mounting position of the thread guide 43 vertically, the thread handling amount can be adjusted without affecting the needle thread feed regulating device 21. That is, when the mounting position of the thread guide 43 is adjusted so that the eyelet 47 of the thread guide 43 may be positioned beneath the top dead center of the thread guide 46, which is disposed on the needle bar right above the needle 14, in the descending stroke of the needle bar 12 from the top dead center, the needle thread 25 is not drawn out by the needle 14 until the thread guide 46 descends to the level of the eyelet 47, and the thread handling amount is small. Therefore, the thread handling amount may be decreased as the mounting position of the thread guide 43 is lowered.
FIG. 7 shows an overedge sewing machine for forming overedge stitches by two needles of stitch type 514, in which left needle 51a and right needle 51b are attached to the needle bar 12, and needle thread 52 for the left needle and needle thread 53 for the right needle are passed from the thread supply sources to the left needle 51a and right needle 51b through thread tensioners 54, needle thread feed regulating device 55 and thread guide 56.
The needle thread feed regulating device 55 is composed of U-shaped thread guide 58, and oscillating thread guide 59 mounted on oscillating lever 15 as shown in detail in FIGS. 8, 9. The thread guide 58 is affixed to a pin 61, which is supported in a manner so as to turn and be fixed to the bracket 60. The bracket 60 is fastened to the arm 11a of the sewing machine 11 through screws 60a and eyelets 62 for needle thread 52 and eyelets 63 for needle thread 53 are formed in the thread guide. On the other hand, on the cam plate 59a of the oscillating thread guide 59, a cam part 64 and a cam part 65 are formed, which act on the needle thread 52 and needle thread 53 to take up, pull off and compensate the thread supply.
The thread pull-off amount can be adjusted by turning the thread guide 58 pin 61 and varying its mounting position, and this adjustment is done the same as in the previous embodiment, on the basis of the reference position which is determined at the position where an optimum stitch for specific cloth and thread type can be formed. In the case of this embodiment, the reference position is determined when the oscillating thread guide 59 is at the bottom dead center position, by turning and fixing the thread guide 58 so that the contours of the thread guide 58 and the cam plate 59a may be matched at the portions D and E shown in FIG. 8.
The effect of the adjustment of mounting position of the thread guide 58 on the thread pull-off amount and thread handling amount by the cam part 65 is explained by referring to FIG. 9.
When the thread guide 58 is turned from the reference position indicated by double dot chain line in FIG. 9 to the position of the solid line and the position of the eyelets 63 are changed from point V to point W and fixed, the cam plate 59a, turning in the counterclockwise direction along with the raising of the oscillating lever 15, picks up the needle thread 53 between the eyelets 63 at the top dead center by means of the cam part 65, as indicated by the solid line, and draws out the thread from the thread supply source. The thread pull-off amount UW at this time is, as compared with the thread pull-off amount UV when the thread guide 58 is at the reference position, twice as much as (UW-UV).
When the cam plate 59a moves downward from its highest point the needle thread 53 is handled at the cam part 65, and the thread slack is compensated for, but since the movement from point V to W is effected in the direction of the locus of turning of the cam part 65, not in the lift L direction of the cam part 65, that is, not in the radial direction nor the direction for varying the distance from the shaft 19, the change in the thread handling amount due to movement from point V to W becomes small. In this way, the thread draw amount can be increased or decreased without affecting the stitch forming process.
The needle thread feed regulating devices shown in FIGS. 10 to 12 are applied to an overedge sewing machine for forming overedge stitches by one needle of stitch type 503. The device comprises a U-shaped thread guide 74 similar to the thread guide 5, and an oscillating thread guide 75. The device shown in FIG. 12 comprises a U-shaped thread guide 74' and an oscillating thread guide 75. The U-shaped thread guide 74 (74') is supported in a manner so as to turn and be fixed on a pin 72 in a bracket 71 mounted on the sewing machine arm 11a and has a pair of eyelets 73 provided on its U-shaped ends. The oscillating thread guide 75 is mounted on an oscillating lever 15. The oscillating thread guide 75. has a cam part 76 on a cam plate 75a used in forming a stitching pitch of 8 stitches or more per inch, and an eyelet 77 used for forming a slightly longer stitch pitch than 8 stitches per inch. This cam part 76 or the eyelet 77 acts on the needle thread passed through the eyelet 73, as in the previous embodiment, so as to take up, pull off, and compensate the needle thread.
In the embodiment of FIG. 10, the reference position is the portion F for using the cam part 76 and, in the FIG. 12, the portions G and, H for using the eyelets 77. In these cases the thread guides 74, 74' are turned and fixed so that the contours of the thread guide 74 and oscillating thread guide 75, positioned at the lowest point, may be matched with each other at their reference portions.
When varying the draw amount of thread, the thread guide 74 is turned about the pin 72 and fixed. For example, in FIG. 11, when the thread guide 74 is changed in mounting position from the position of the double dot chain line to the position of the solid line, the draw amount of the thread by the cam part 76 when the oscillating thread guide 75 reaches its lowest point becomes twice as large (YZ-XZ), but since the movement direction of the eyelet 73 is approximate to the oscillating direction of the cam plate 75a, the change in the thread handling amount by the cam part 76 is extremely small as in the previous embodiment. | A needle thread feed regulating device utilized in high speed overedge sewing machines which form safety stitches composed of overedge stitches and double chain stiches. The needle thread feed regulating device comprises a thread guide mounted on the sewing machine frame and an oscillating thread guide which moves in cooperation with the sewing machine main shaft. The oscillating thread guide has a cam plate which regulates the feed of both the thread for overedge stitches and the thread for double chain stitches. | 3 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a cerdip type of solid-state image sensing device, a structure and a method for gripping the cerdip type of solid-state image sensing device for using in the interior of an image reading apparatus such as a copying machine, an image scanner, a facsimile or the like.
[0003] 2. Description of the Prior Art
[0004] Generally, an image reading apparatus which is incorporated in an imaging apparatus and reads an image as an optical image by use of a solid-state image sensing device such as a CCD and so on is configured to read by focusing an object 53 on a solid-state image sensing device 61 through a focused lens 52 as shown in FIG. 10.
[0005] The used solid-state image sensing device 61 has a plurality of micro-photoelectric transfer devices (hereinafter, referred to as pixels each having normally a micro-size of several μm by several μm) in which a pixel line 31 is arranged in one straight line.
[0006] In such an image reading apparatus, a linear image focused by the focused lens 52 is positioned on the solid-state image sensing device 61 and the focused lens 52 or one linear pixel line 31 of the solid-state image sensing device 61 must be micro-motioned about X, Y and Z axes, in rotational directions of β and γ about Y and Z axes, respectively, (three axes and two rotational directions in five axes of X, Y, Z, β and γ axes) for adjusting a position thereof to read optical characteristic (focusing, magnification and so on) with a predetermined accuracy, as shown in FIG. 11.
[0007] Note that reference numeral 8 denotes an optical axis.
[0008] Here, a reason that adjustment is not effected with respect to an α axis about the X axis is as follows.
[0009] When the β and γ axes which are vertical with the pixel line is not adjusted, a distance between the focused lens 52 and solid-state image sensing device 61 is different every the pixel to deteriorate the accuracy of optical characteristic. On the contrary, since the X axis is parallel with the pixel line, the distance between the focused lens 52 and solid-state image sensing device 61 is not different every the pixel, and thus the optical characteristic is not subjected to an influence.
[0010] On the other hand, in recent, there may be used a solid-state image sensing device having three pixel lines 31 a, 31 b and 31 c linearly arranged in every pixels R, G and B which have a peak of spectral sensitivity in Red, Green and Blue to read color images as shown in FIG. 12.
[0011] Normally, a high precision is required to position adjustment of the solid-state image sensing device in 5 axis directions. There is required a technic to accomplish such requirement in which if the solid-state image sensing device is attached to a frame, after position of the solid-state image sensing device is adjusted as described above, the position of the solid-state image sensing device is not deviated from the frame.
[0012] A reason why such technic is required is because of requiring readjustment even though the high precision for the adjustment is performed when the position of the solid-state image sensing device deviates from the frame on attachment and requiring disposal of an attached part in a case of adopting an attaching method which is not separatable, thereby bringing to a long positioning adjustment and resulting in a high cost attaching method.
[0013] The solid-state image sensing device 61 is, also, mounted on a base 12 within the imaging apparatus. The base 12 drives the solid-state image sensing device 61 and acts to transmit an electrical output signal of the solid-state image sensing device 61 according to an optical image to a control section (not shown) of the image reading apparatus after the electrical output signal is electrically processed.
[0014] If an object to be read in the image reading apparatus is an image, a line type of solid-state image sensing device in which a plurality of micro photoelectric transfer devices are disposed in one line is almost used. In this case, the image is read as a linear image. In a color image reading apparatus for reading a color image, a color solid-state image sensing device having three lines 31 a, 31 b and 31 c in which pixels having a peak of spectral sensitivity in Red (hereinafter referred to as R), Green (hereinafter referred to as G) and Blue (hereinafter referred to as B) are arranged in three lines every R, G and B is used (see FIG. 12).
[0015] Furthermore, the solid-state image sensing device is classified in several kind by an outside structure (package structure). In recent, the cerdip type of solid-state image sensing devise is increasingly used even in an image reading apparatus for a low production cost.
[0016] [0016]FIG. 13 is a sectional view showing a basic structure of a conventional cerdip type of solid-state image sensing device (for color, herein).
[0017] The cerdip type of solid-state image sensing device has a construction as follows.
[0018] A CCD chip 63 which is a chip of the solid-state image sensing device is mounted on a base 62 of ceramic. Pixel lines 31 a, 31 b and 31 c are formed on the CCD chip 63 . A lead frame 65 is secured to the base 62 by means of sealed glass 64 and is electrically connected to the CCD chip 63 by wire-bonding between the lead frame 65 and CCD chip 63 with a lead wire 68 . A wind frame 66 is bonded with the sealed glass 64 . A transparent cover glass 67 is secured to the wind frame 66 to seal the CCD chip 63 .
[0019] As described above, in the image reading apparatus, the linear image focused by the focused lens 52 is positioned on the solid-state image sensing device 61 and the solid-state image sensing device 61 must be micro-motioned along or about the five axes of X, Y, Z, β and γ as shown in FIG. 11 for adjusting a position thereof to read the optical characteristic (focusing, magnification and so on) with a predetermined accuracy during a producing step of the image reading apparatus.
[0020] Then, normally, an accuracy of the positioning adjustment of the solid-state image sensing device is μm or 0.001° order in all the five axes.
[0021] Here, the optical axis 8 in FIGS. 11 and 13 corresponds to a direction of the Z axis in a coordinate.
[0022] Directions of the X and Y axes correspond to main and sub scanning directions, respectively in the image reading apparatus.
[0023] Further, α is about the X axis, β is about the Y axis and γ is about the Z axis.
[0024] It is necessary to grip the solid-state image sensing device 61 with a producing apparatus (not shown) on production to perform the position adjustment as described above.
[0025] It, then, is considered that the solid-state image sensing device is not directly gripped, the base on which the solid-state image sensing device is mounted is gripped as an object of gripping.
[0026] However, the base 12 has a problem in a point of stiffness since the base comprises a thin plate and normally, does not make of a material having a high stiffness.
[0027] Upon gripping of a base having a low stiffness, the gripping causes the base to deform resiliently to occur change of position of the solid-state image sensing device 61 . There is no problem on this fact if a product has a low adjusting accuracy, but, if the solid-state image sensing device is used for an image reading apparatus to which a high accuracy should be requested, this deformation of the base becomes a large problem.
[0028] Under the aforementioned circumstances, it is desirable that the solid-state image sensing device is directly gripped as an object of gripping on production.
[0029] In prior art, the cerdip type of solid-state image sensing device which is economically advantageous, as described above has no any part suitable to grip. Namely, since a side 62 a of the base 62 and a side 66 a of the wind frame 66 are closing as shown in FIG. 14, there is no plane of gripping by a chuck.
[0030] Note that in FIG. 14, only a positional relationship of the base 62 and wind frame 66 is magnifically shown and the sealed glass 64 and cover glass 64 and so on are omitted. A side 61 a may not be a gripped plane of a chuck for projection of the side of the sealed glass 64 as shown in FIG. 13.
[0031] As described above, there is no a cerdip type of solid-state image sensing device in which ability of gripping is considered in the prior art.
[0032] In a such condition, a gripping portion of the device must be provided on the base 12 .
[0033] This results in elimination of adjusting accuracy of the image reading apparatus or a high cost of the image reading apparatus by no using the cerdip type of solid-state image sensing device. As a result, it is not compatible with an image reading quality and economics.
SUMMARY OF THE INVENTION
[0034] From the above circumstances, it is an object of the present invention to provide a cerdip type of solid-state image sensing device and a structure and a method for gripping the solid-state image sensing device.
[0035] To accomplish the above object, a cerdip type of solid-state image sensing device according to one aspect of the present invention is characterized by comprising a base on which photoelectric transfer devices are arranged in line along a main scanning direction, a sealed glass disposed on said base for fixing a lead frame, a wind frame disposed on said sealed glass, a transparent cover glass disposed on said wind frame, and gripped surface means for gripping said cerdip type of solid-state image sensing device.
[0036] The gripped surface means is formed by grinding a portion of outer peripheral surfaces of said base, sealed glass, wind frame and cover glass after they are superposed.
[0037] A cerdip type of solid-state image sensing device according to the other aspect of the present invention is characterized by comprising a base on which photoelectric transfer devices are arranged in line along a main scanning direction, a sealed glass disposed on said base for fixing a lead frame, a wind frame disposed on said sealed glass, a transparent cover glass disposed on said wind frame, and gripped surface means provided on said cerdip type of solid-state image sensing device to grip it.
[0038] The gripped surface means is composed of side surfaces of one or more of said base, sealed glass, wind frame and cover glass.
[0039] The side surfaces which are gripped are parallel with a direction that said base, sealed glass, wind frame and cover glass are superposed and said main scanning direction, and most project over the side surfaces which are not gripped in a vertical direction to a plane including said superposed and main scanning directions.
[0040] One example, the gripped surface means may be composed of the side surfaces of said base, sealed glass and wind frame.
[0041] The gripped surface means may be composed of the side surfaces of said base and wind frame.
[0042] The gripped surface means may be comprised of the surfaces of said base and sealed glass.
[0043] The gripped surface means may be composed of the side faces of said sealed glass and wind frame. Gripped surface means is composed of the side surfaces of said base.
[0044] The gripped surface means may be composed of the side surfaces of said sealed glass.
[0045] The gripped surface means may be composed of the side surfaces of said wind frame.
[0046] According to the other aspect of the present invention, provided is a structure for gripping a cerdip type of solid-state image sensing device comprising a base on which photoelectric transfer devices are arranged in line along a main scanning direction, a scaled glass disposed on said base for fixing a lead frame, a wind frame disposed on said sealed glass, a transparent cover glass disposed on said wind frame and gripped surface means provided on one or more of said base, sealed glass, wind frame and cover glass for gripping said cerdip type of solid-state image sensing device.
[0047] According to the further other aspect of the present invention, provided is a method for gripping a cerdip type of solid-state image sensing device comprising preparing a base on which photoelectric transfer devices are arranged in line along a main scanning direction, disposing a sealed glass on said base for fixing a lead frame, disposing a wind frame on said sealed glass, disposing a transparent cover glass on said wind frame and providing gripped surface means on one or more of said base, sealed glass, wind frame and cover glass for gripping said cerdip type of solid-state image sensing device.
BRIEF DESCRIPTION OF THE DRAWINGS
[0048] [0048]FIG. 1 is a sectional view of a cerdip type of solid-state image sensing device in a first embodiment according to the present invention.
[0049] [0049]FIG. 2 is a view showing a state of gripping the cerdip type of solid-state image sensing device in FIG. 1 by a chuck of a producing apparatus in an image reading apparatus, (A) is a view as viewed from the same direction as the cerdip type of solid-state image sensing device in FIG. 1, (B) is a view showing a cover glass from a direction of a Z axis.
[0050] [0050]FIG. 3 is a view showing a modification of gripping the cerdip type of solid-state image sensing device in FIG. 1 by the chuck of the producing apparatus in the image reading apparatus and is a view showing the cover glass from the Z axis direction similarly to FIG. 2(B).
[0051] [0051]FIG. 4 is a view showing a cerdip type of solid-state image sensing device in a second embodiment according to the present invention and is a view as viewed from the same direction as the cerdip type of solid-state image sensing device in FIG. 1, similarly to FIG. 2(A).
[0052] [0052]FIG. 5 is a view showing a cerdip type of solid-state image sensing device in a third embodiment according to the present invention and is a view as viewed from the same direction as the cerdip type of solid-state image sensing device in FIG. 1, similarly to FIG. 2(A).
[0053] [0053]FIG. 6 is a view snowing a cerdip type of solid-state image sensing device in a fourth embodiment according to the present invention and is a view as viewed from the same direction as the cerdip type of solid-state image sensing device in FIG. 1, similarly to FIG. 2(A).
[0054] [0054]FIG. 7 is a view showing a cerdip type of solid-state image sensing device in a fifth embodiment according to the present invention and is a view as viewed from the same direction as the cerdip type of solid-state image sensing device in FIG. 1, similarly to FIG. 2(A).
[0055] [0055]FIG. 8 is a view showing a cerdip type of solid-state image sensing device in a sixth embodiment according to the present invention and is a view as viewed from the same direction as the cerdip type of solid-state image sensing device in FIG. 1, similarly to FIG. 2(A).
[0056] [0056]FIG. 9 is a view showing a cerdip type of solid-state image sensing device in a seventh embodiment according to the present invention and is a view as viewed from the same direction as the cerdip type of solid-state image sensing device in FIG. 1, similarly to FIG. 2(A).
[0057] [0057]FIG. 10 is a view showing an optical poisoning relationship of an object and a focus lens.
[0058] [0058]FIG. 11 is a view showing a coordinate of six axes in a solid-state image sensing device and the focus lens.
[0059] [0059]FIG. 12 is a font view showing a conventional solid-state image sensing device.
[0060] [0060]FIG. 13 is a sectional view showing a basic construction of the conventional cerdip type of solid-state image sensing device.
[0061] [0061]FIG. 14 is a perspective view showing side surfaces of the cerdip type of solid-state image sensing device.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0062] A first embodiment of a cerdip type of solid-state image sensing device 1 according to the present invention is shown in FIG. 1.
[0063] The cerdip type of solid-state image sensing device 1 is constructed to superpose a base 2 of ceramic, a CCD chip 3 mounted on the base 2 , a sealed glass 4 provided on an outer periphery of the CCD chip 3 on the base 2 , a wind frame 6 of ceramic attached through the sealed glass 4 to the base 2 and a cover glass 7 attached to the wind frame 6 to seal the CCD chip 3 .
[0064] The cerdip type of solid-state image sensing device 1 is provided with a gripped structure which comprises gripped surface means. The gripped surface means is formed from side surface means which is, for example, composed of upper and lower side surfaces 2 a of the base 2 , upper and lower side surfaces 4 a of the sealed glass 4 and/or upper and lower side surfaces 6 a of the wind frame 6 .
[0065] These side surfaces 2 a, 4 a and 6 a form the same plane.
[0066] The gripping surface means is parallel to a plane including a superposed direction, namely, an optical direction and a main scanning direction (direction of the pixel lines, namely, vertical direction to a surface of the drawing) and has a surface more projected in a direction vertical to a plane including the superposed and main scanning directions.
[0067] The gripping surface means (comprising the side surfaces 2 a, 4 a and 6 a ) can be engaged with an engaged surface 10 a of a chuck 10 for adjustment.
[0068] For example, the side surfaces 2 a, 4 a and 6 a are simultaneously ground by holding with a jig after the base 2 and wind frame 6 are bonded by the sealed glass 4 in order to form the side surfaces 2 a, 4 a and 6 a in a parallel condition with the plane including the optical and main scanning directions.
[0069] [0069]FIG. 2 is a view showing a gripped condition of the cerdip type of solid-state image sensing device in FIG. 1 by means of the chuck in an apparatus for producing the image reading apparatus, (A) is a view showing the cerdip type of solid-state image sensing as viewed from the same direction as FIG. 1 and (B) is a view showing the cover glass as viewed from the direction of the same Z axis as in FIG. 13 (see FIG. 1).
[0070] As shown in FIG. 2(A), upon production of the image reading apparatus, in order to adjust a position of one or more lenses and the cerdip type of solid-state image sensing device 1 , the chuck 10 in the producing apparatus grips the side surfaces 2 a, 4 a and 6 a from upward and downward.
[0071] Here, the engaged surface 10 a of the chuck 10 which engages with the cerdip type of solid-state image sensing device is, also, formed into a plain which is parallel with the plane including the directions of the optical axis and main scanning.
[0072] As shown in FIG. 2(B), the side surface means gripped by the chuck 10 is not provided with the same lead frames 5 as the lead frames 65 as described above in FIG. 13. The lead frames 5 are disposed on the longitudinal opposed ends of the solid-state imaging sensing device. As a result, the side surface means between the lead frames are selected as the gripped surface means gripped by the chuck. For this reason, the lead frames and lead lines are omitted in FIGS. 1 to 9 .
[0073] In FIG. 2(B), three chucks are used to grippe the cerdip type of solid-state image sensing device 1 in which the two chucks grip the upper side surfaces of the device 1 and one chuck grips the lower side surfaces of the device 1 . One chuck may be disposed on each of the upper and lower side surfaces, without being limited to the three chucks.
[0074] As described above, according to the aforementioned cerdip type of solid-state image sensing device of the first embodiment, because it has the gripped structure in which the gripped surface means parallel with the plane including the optical and main scanning directions is provided, and this gripped surface means can be directly gripped by the chuck 10 having the engaged surface 10 a which similarly is parallel with the plane including the optical and main scanning directions, it is able to provide an image reading apparatus having a very high accuracy of positioning adjustment by use of the cerdip type of solid-state image sensing device 1 having a lower cost. It is, also, able to maintain a enough contacting area which can be gripped although the cerdip type of solid-state image sensing device 1 is formed to thin, since the gripped surface means is composed of the side surfaces 2 a, 4 a and 6 a.
[0075] There is, also, an advantageous effect that adjustment of the direction of the α axis is not required, since the gripped surface means of the cerdip type of solid-state image sensing device 1 and engaged surface 10 a of the chuck 10 are parallel with the plane including the optical and main scanning directions.
[0076] [0076]FIG. 3 shows a modification of gripping the cerdip type of solid-state image sensing device as shown in FIG. 1 by a chuck 11 in a producing apparatus of an image reading apparatus. FIG. 3 is a view of the cover glass side viewed from the direction of the Z axis similarly to FIG. 2(B).
[0077] As shown in FIG. 3, the chuck 11 has a form of air-suction. The air-suction type of chuck 11 has an engaged surface 11 a formed to correspond to a plane for contacting with the gripped surface means of the cerdip type of solid-state image sensing device 1 . More specifically, the engaged surface 11 a contacts tightly with the gripped surface means and sucks to grip it.
[0078] The chuck 11 may be used in either the upper side surfaces or the lower side surfaces of the cerdip type of solid-state image sensing device 1 .
[0079] Alternatively, the two chucks 11 may be provided on both the upper and lower side surfaces of the cerdip type of solid-state image sensing device 1 . Also, a plurality of chucks may be disposed on one of the upper and lower side surfaces. The chuck 11 may be replaced by a chuck 10 used in embodiments which will be described hereinafter.
[0080] [0080]FIG. 4 shows a cerdip type of solid-stated image sensing device in a second embodiment according to the present invention and is a view showing the same state as the cerdip type of solid-state image sensing device of FIG. 1, similarly to FIG. 2(A).
[0081] Side surface means of the cerdip type of solid-state image sensing device 1 in the second embodiment is composed of upper and lower side surfaces 2 a of the base 2 and upper and lower side surfaces 6 a of the wind frame 6 . These side surfaces place in the same plane as gripped surface means gripped by any chuck 10 .
[0082] The side surfaces are parallel with the plane including optical and main scanning directions as described above and most project to a direction vertical to the plane including the optical and main scanning directions, namely from the other side surfaces of the device 1 .
[0083] These side surfaces 2 a and 6 a contact with an engaged surface 10 a of the chuck 10 for adjustment of position.
[0084] In order to form the side surfaces 2 a and 6 a in a parallel state with the plane including the optical and main scanning directions, for example, after the base 2 and wind frame 6 are bonded by the sealed glass 4 to project from the side surfaces 4 a of the sealed glass 4 in sideward, the side surfaces 2 a and 6 a are simultaneously ground with the cerdip type of solid-state image held by a jig.
[0085] Since the side surfaces 2 a and 6 a project over the side surface 4 a after grinding, the side surface 4 a may be any configuration, for example, a flat, convex, concave surface or the like.
[0086] In the cerdip type of solid-state image sensing device 1 in the second embodiment, since the side surface means is composed of the side surfaces 2 a and 6 a of the base 2 and wind frame 6 which are made of ceramic having a high stiffness, as compared with the first embodiment, even though a gripped area is less, the same gripped accuracy can be obtained. Also, the same material is ground and therefore a high ground performance is obtained. Further, a used amount of the sealed glass 4 is minimized.
[0087] [0087]FIG. 5 shows a cerdip type of solid-state image sensing device in a third embodiment according to the present invention and is a view as viewed from the same direction as the cerdip type of solid-state image sensing device in FIG. 1.
[0088] Side surface means of the cerdip type of solid-state image sensing device in the third embodiment is composed of the side surfaces 2 a and 4 a of the base 2 and sealed glass 4 .
[0089] The side surfaces 2 a and 4 a are the same plane and are parallel with the plane including the optical and main scanning directions, and further most project in the vertical direction to the plane including the optical and main scanning directions, as described above. These side surfaces contact with the aforementioned engaged surface 10 a of the chuck 10 for adjustment.
[0090] In order to form the side surfaces 2 a and 4 a in a parallel state with the plane including the optical and main scanning directions, for example, after the base 2 and wind frame 6 are bonded by the sealed glass 4 , the side surfaces 2 a and 6 a are simultaneously ground with the cerdip type of solid-state image held by a jig.
[0091] Since the side surfaces 2 a and 4 a project over the side surfaces 6 a after grinding, the side surfaces 6 a may be any configuration, for example, a flat, convex, concave surface or the like.
[0092] [0092]FIG. 6 shows a cerdip type of solid-state image sensing device in a fourth embodiment according to the present invention and is a view as viewed from the same direction as the cerdip type of solid-state image sensing device in FIG. 1.
[0093] Side surface means of the cerdip type of solid-state image sensing device in the fourth embodiment is composed of the side surfaces 4 a and 6 a of the sealed glass 4 and wind frame 6 .
[0094] The side surfaces 4 a and 6 a are the same plane and are parallel with the plane including the optical and main scanning directions, and further most project in the vertical direction to the plane including the optical and main scanning directions, as described above. These side surfaces contact with the aforementioned engaged surface 10 a of the chuck 10 for adjustment.
[0095] In order to form the side surfaces 4 a and 6 a in a parallel state with the plane including the optical and main scanning directions, for example, after the base 2 and wind frame 6 are bonded by the sealed glass 4 , the side surfaces 4 a and 6 a are simultaneously ground with the cerdip type of solid-state image held by a jig.
[0096] Since the side surfaces 4 a and 6 a project over the side surfaces 2 a after grinding, the side surfaces 2 a may be any configuration, for example, a flat, convex, concave surface or the like.
[0097] [0097]FIG. 7 shows a cerdip type of solid-state image sensing device in a fifth embodiment according to the present invention and is a view as viewed from the same direction as the cerdip type of solid-state image sensing device in FIG. 1.
[0098] Side surface means of the cerdip type of solid-state image sensing device in the fifth embodiment is composed of the side surfaces 2 a of the base 2 .
[0099] The side surfaces 2 a are the same plane and are parallel with the plane including the optical and main scanning directions, and further most project in the vertical direction to the plane including the optical and main scanning directions, as described above. The side surfaces 2 a contact with the aforementioned engaged surface 10 a of the chuck 10 for adjustment.
[0100] In order to form the side surfaces 2 a in a parallel state with the plane including the optical and main scanning directions, for example, after the base 2 and wind frame 6 are bonded by the sealed glass 4 , the side surfaces 2 a are ground with the cerdip type of solid-state image held by a jig.
[0101] Since the side surfaces 2 a project over the side surface 4 a and 6 a after grinding, the side surface 4 a and 6 a may be any configuration, for example, a flat, convex, concave surface or the like. Also, the thickness (length of the optical direction) of the side surfaces 2 a of the base 2 may be large depending on a necessary accuracy. For example, the thickness is preferably 2 to 3 mm.
[0102] [0102]FIG. 8 shows a cerdip type of solid-state image sensing device in a sixth embodiment according to the present invention and is a view as viewed from the same direction as the cerdip type of solid-state image sensing device in FIG. 1.
[0103] Side surface means of the cerdip type of solid-state image sensing device in the sixth embodiment is composed of the side surfaces 6 a of the wind frame 6 .
[0104] The side surfaces 6 a are the same plane and are parallel with the plane including the optical and main scanning directions, and further most project in the vertical direction to the plane including the optical and main scanning directions, as described above. The side surfaces 6 a contact with the aforementioned engaged surface 10 a of the chuck 10 for adjustment.
[0105] In order to form the side surfaces 6 a in a parallel state with the plane including the optical and main scanning directions, for example, after the base 2 and wind frame 6 are bonded by the sealed glass 4 , the side surfaces 6 a are ground with the cerdip type of solid-state image held by a jig.
[0106] Since the side surfaces 6 a project over the side surfaces 2 a and 4 a after grinding, the side surfaces 2 a and 4 a may be any configuration, for example, a flat, convex, concave surface or the like. Also, the thickness (length of the optical direction) of the side surfaces 6 a of the wind frame 6 may be large depending on a necessary accuracy. For example, the thickness is preferably 2 to 3 mm.
[0107] [0107]FIG. 9 shows a cerdip type of solid-state image sensing device in a seventh embodiment according to the present invention and is a view as viewed from the same direction as the cerdip type of solid-state image sensing device in FIG. 1.
[0108] Side surface means of the cerdip type of solid-state image sensing device in the seventh embodiment is composed of the side surfaces 4 a of the sealed glass 4 .
[0109] The side surfaces 4 a are the same plane and are parallel with the plane including the optical and main scanning directions, and further most project in the vertical direction to the plane including the optical and main scanning directions, as described above. The side surfaces 4 a contact with the aforementioned engaged surface 10 a of the chuck 10 for adjustment.
[0110] In order to form the side surfaces 4 a in a parallel state with the plane including the optical and main scanning directions, for example, after the base 2 and wind frame 6 are bonded by the sealed glass 4 , the side surfaces 4 a are ground with the cerdip type of solid-state image held by a jig.
[0111] Since the side surfaces 4 a project over the side surfaces 2 a and 4 a after grinding, the side surfaces 2 a and 6 a may be any configuration, for example, a flat, convex, concave surface or the like. Also, the thickness (length of the optical direction) of the side surfaces 4 a of the sealed glass 4 may be large depending on a necessary accuracy. For example, the thickness is preferably 2 to 3 mm.
[0112] As described above, according to the present invention, it is able to use the cerdip type of solid-state image sensing device having a low cost because the cerdip type of solid-state image sensing device has the gripped structure comprises a plurality of side surfaces which are parallel with the optical and main scanning directions and most project in the vertical direction to the plane including the optical and main scanning directions to be gripped effectively by the chuck, whereby enabling the high-accuracy adjustment of position of the cerdip type of solid-state image sensing device in a step of producing the image reading apparatus.
[0113] Although the some embodiments have been described, the present invention is not limited to these embodiments and various changes and modifications can be made without departing the gist of the present invention. | Disclosed is a cerdip type of solid-state image sensing device having a simple construction, capable of directly gripping and performing a positioning adjustment of a high accuracy. The cerdip type of solid-state image sensing device comprises a base on which photoelectric transfer devices are arranged in line along a main scanning direction, a sealed glass disposed on said base for fixing a lead frame, a wind frame disposed on said sealed glass, a transparent cover glass disposed on said wind frame, and gripped surface means for gripping said cerdip type of solid-state image sensing device. | 7 |
BACKGROUND OF THE INVENTION
The present invention relates to a new and improved transport system or installation for use in spinning preparation for transporting laps from a first machine to a second machine by means of carriers or supports which are movable along transport rails located above head height, the laps carried by the transport rails being located at a greater height above the ground than the laps deposited at the lap transfer locations of the machines, and a carrier rail movable in the vertical direction being provided for the carriers at each lap transfer location.
From German Published Pat. No. 1,288,490, published Jan. 30, 1969 a system is known in which lap carriers travel along an endless transport path at a predetermined mutual spacing from one another. The laps to be transferred to the lap carriers are lifted and grasped by the continually moving lap carriers. The laps can only be transferred individually and transported at the same mutual spacing. This system does not permit simultaneous delivery of a group of laps. Return of empty bobbin tubes by the transport system is also not possible. Rather, the empty bobbin tubes must be returned by a special transport system.
German Utility Model No. 7,424,750 relates to a device which also has an endless transport belt for automatic transport of laps. In this case, the lap carriers and empty package carriers which are separate from the lap carriers travel along the transport belt. In this device also a plurality of laps cannot be delivered simultaneously nor can a plurality of bobbin tubes be carried away simultaneously.
Japanese Patent Specification No. 47-46852 teaches a system in which a plurality of lap carriers are passed simultaneously to a transport rail by means of a carrier rail. This transport rail does not form a closed circulation path, so that the lap carriers must be returned along the same path on which they were delivered to a machine. Thus, freedom in transporting the carriers is reduced. Also, the carriers have no means or facility serving for return of empty bobbin tubes. Accordingly, with this transport system or installation also special means serving for the latter purpose must be provided.
SUMMARY OF THE INVENTION
Therefore, with the foregoing in mind it is a primary object of the present invention to provide an improved transport system for spinning preparation which is not afflicted with the aforementioned drawbacks and limitations of the prior art.
Still a further significant object of the present invention is to provide an improved transport system for spinning preparation which enables transport of both the lap and also the empty bobbin tube along an orderly and simple circulation path or track.
Another important object of the present invention is to provide an improved transport system of the character described which is relatively simple in construction and design, quite economical to manufacture, highly reliable and versatile in operation, not readily subject to breakdown and malfunction, and requires a minimum of maintenance and servicing.
Now in order to implement these and still further objects of the invention, which will become more readily apparent as the description proceeds, the inventive transport system for use in spinning preparation is manifested by the features that, the transport rails and the carrier rails brought to the height of the transport rails form components or parts of a closed, endless circulation path or track and each carrier has a holder for the lap and a holder for the empty bobbin tube. The invention thus permits transport of both the lap and also the empty bobbin tube along an ordered and simple circulation path or track.
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 where throughout the various figures of the drawings there have been conveniently used the same reference characters to denote the same or analogous components or parts and wherein:
FIG. 1 shows a schematic representation, viewed from above, of a transport system arranged between a sliver lap machine and a ribbon lap machine;
FIG. 2 shows a schematic side view taken substantially along the line II--II of FIG. 1; and
FIG. 3 shows a schematic representation, viewed from above, of a transport system located between a ribbon lap machine and a combing machine.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Describing now the drawings, it will be understood that it order to simplify the illustration thereof only enough of the details of the transport system and related structure have been shown as needed for those skilled in the art to readily understand the underlying principles and concepts of the present invention. In accordance with the showing of FIGS. 1 and 2 there is provided a sliver lap machine 11 to which non-illustrated fiber slivers are fed from sliver cans 12 or the like. In the sliver lap machine 11 the fiber slivers are combined to form a sheet or web and laps 13 are formed from the latter. One of the laps, such as the lap 13a, is shown located at a lap transfer location 43 at the sliver lap machine 11. Transport rails 14 are part of a closed, endless circulation path or track for carriers or supports 15 which are movable along this circulation path or track. The carriers 15 serve for carrying and transporting the laps 13 and empty or bare bobbin tubes 26. During such transport, they move in the direction indicated by the arrow 23.
A carrier or support rail 16 and carrier or support rails 17, 18, which are movable in a substantially vertical direction, also form components or parts of the circulation path or track. In this embodiment the latter is constituted by the transport rails 14 and the carrier rails 16, 17, 18. The carrier rail 16 is vertically movable up and down between a position which it adopts for grasping of a lap 13a located at the lap transfer location 43 and the height of the transport rails 14. In FIG. 2, the lap 13a is located at the lap transfer location 43 in a position in which it is grasped by the carrier or support 15, and the carrier rail 16 is located at its height or position appropriate for such grasping of the lap 13a. In FIG. 2, the carrier rail 18 is also located in its lowered position relative to the height of the transport rails 14, in which position three laps 13 deposited from the carrier rail 18 are laid upon the lap transfer location 80 of the ribbon lap machine 24. Vertical movements of the carrier rails 16, 17 and 18 are caused by the lifting or displacement devices 19, 20 and 21 illustrated schematically in FIG. 1. Each of the carrier rails 17, 18 is designed for taking-up, for instance, three laps 13. These laps 13 are deposited in groups of three from the carrier rails 17, 18 on corresponding lap transfer locations.
The laps 13 are wound-up on respective tubes 26a. Each carrier or support 15 comprises a holder or holder member 25 for a lap 13. Each such holder 25 comprises, in the illustrated exemplary embodiment, a clamp 25a with clamping elements 25b movable relative to each other and which extend into the wound tube 26a from both end faces thereof in order to grasp a lap 13. The carrier or support 15 also comprises a holder 28 for the empty tubes 26. This holder 28 comprises, in the illustrated exemplary embodiment, a bar or rod 28a which extends radially away from the position at which it is mounted or fastened and which is joined with a bar or rod portion 29 extending at an angle thereto. Bar portion 29 extends rearwardly with reference to the transport direction of the carrier 15 and its rearward end forms a free end. The empty tubes 26 to be transported are placed or pushed onto the bar or rod portions 29. A stop or abutment 30 fixed with reference to the transport system serves for taking off the tube 26 from bar portion 29. Each carrier 15 is supported by rollers 27 and is conveyable by means of these rollers 27 along the transport rails 14 and the carrier rails 16, 17, 18.
The transport rails 14 are mounted on a frame 31. They are located above head height. For clarity of illustration, the carriers or supports 15 with the holders or holder members 25 and 28 are not shown in FIG. 1. On the other hand, for the same reason, the lifting devices 19, 20 and 21 are not shown in FIG. 2.
In operation of the transport system or installation, a lap 13 or 13a at the lap transfer location 43 of the sliver lap machine 11 is brought to the circulation path or track upon each forward movement of the carriers 15 by one step. For this purpose, the carrier rail 16 together with the carrier 15 located thereon is lowered by means of the related lifting device 19, the lap 13a located at the lap transfer location 43 is grasped by means of the holder 25 of the carrier 15 and the carrier rail 16 is lifted again by means of the lifting device 19 to the height at which the carrier rail 16 is now aligned with the transport rail 14.
With the carrier or support rail 16 raised, the carrier or support 15 located thereon together with the lap 13 or 13a carried thereby is moved further stepwise by any suitable and therefore not particularly illustrated means along the transport rail 14 in the direction of the arrow 23.
By means of the lifting devices 20 and 21 respective groups of three laps 13 are deposited simultaneously at the ribbon lap machine 24. The lowering of these lap groups is carried out alternately. If three laps 13 are required at the lap transfer location 80 associated with the carrier rail 17, then three laps 13 are brought to the carrier rail 17. Then, the latter is lowered and thereafter three tubes 26 released at the ribbon lap machine 24 from delivered laps 13, are donned on the tube holders 28 or bar portions 29 of the three carriers 15 located on the carrier rail 17. Thereafter, the laps 13 are deposited upon the lap transfer location 80 and released. Finally, the carrier rail 17 is again lifted, so that it is aligned once again with the transport rail 14 and the carrier rail 18 to close the previously formed interruption or gap formed therebetween. Thus, the circulation path or track is again closed. When the three laps 13 located on the carrier rail 18 are required, delivery is effected in a procedure which corresponds to that just described with reference to the carrier rail 17. Accordingly, there would not appear to be any necessity for any further detailed description thereof.
After the six laps 13 located at the lap transfer location 80 of the ribbon lap machine 24 have been transferred, and after six empty tubes 26 have been donned and the carrier rails 17, 18 raised again, the carriers 15 are moved further through six steps and six new laps 13 are brought to the ribbon lap machine 24.
The tubes 26 donned onto the holders 28 or bar portions 29 and arriving at the sliver lap machine 11 strike or impact against the stop or abutment 30. They are thus pushed off the bar portions 29. These stripped tubes 26 pass into a receiver 22 and are thereafter ready for reuse for new laps 13.
It is clear that as a result of the closed circulation path or track formed by the transport rails 14 and carrier rails 16, 17 and 18 a simple and thus trouble-free transport of laps 13 and tubes 26 is obtained. This transport arrangement for the laps and tubes can be operated manually to any required extent as desired, or can be automated to a more or less high degree.
The carrier rail 16 is designed for lifting of individual laps 13. In a non-illustrated, modified embodiment a carrier rail serving for simultaneous lifting of a plurality of, for example three, laps is provided. According to a further, modified embodiment, the tube holder can comprise a trough in place of the illustrated bar-shaped embodiment; the empty tubes 26 can be laid in the trough. Also in this case, with the trough arranged essentially parallel to the direction of movement of the carriers, the tubes 26 are pushed out of the trough by a stop 30.
The sliver lap machine 11 delivers the fiber sheet in the form of an endless band. When the lap is full the band must be cut. In an especially advantageous embodiment, the carriers 15 are provided with a holder rod 32 which is biased towards the lap 13 (or 13a). The holder rod 32 is arranged at right angles to the plane of the drawing in FIG. 2. It is carried at each end by an arm 33. These arms 33 are pivotable about an axis or shaft 34 disposed at right angles to the plane of the drawing in FIG. 2. The bias or loading of the holder rod 33 can be produced for example by a non-illustrated spiral spring or the like wound about the axis or shaft 34.
Through the cutting of the band required for the transport of the lap 13 there arises an outer free end 35 on the sheet. The holder rod 32 engaging the lap 13 or 13a holds this end 35 of the sheet, so that the lap 13 can be transported in a trouble-free manner without a loose, dangling portion.
In the illustration of FIG. 2, during grasping of the lap 13a at the sliver lap machine 11, the attendant or operator is located to the left of the lap 13a and can, by pivoting the holder rod 32 about the axis 34, easily draw the end 35 of the sheet between the holder rod 32 and the lap 13a. When the laps 13 have arrived at the ribbon lap machine 24, then the ends 35 of the sheets are located in accordance with FIG. 2 on the left-hand side of the laps 13. This is the side on which the attendant or operator is located. Thus, at this machine the end 35 of the sheet is especially easily accessible and can be fed in a simple manner into the ribbon lap machine 24 for further processing. The lap 13 also comes to rest in such a manner that the sheet is drawn therefrom in the correct rotational sense. It is clear that the construction of the transport system is carried out in such a manner that the end 35 of the sheet and the holder rod 32 are located at both machines 11 and 24 on the side on which the end of the sheet is subjected to manipulation. The advantageous positioning of the lap 13 at both lap transfer locations 43 and 80 is effected by the change of the direction of the transport rail 14 through 180°, that is by virtue of the described construction of the transport system.
In FIG. 3 a further embodiment of a transport system or installation according to the invention is shown. This transport system relates to the transport of laps 36 from a ribbon lap machine 24 to combing machines 37. Once again there are provided transport rails 38a, 38b, generally indicated by 38, for the transport of laps 36 and of empty tubes. Further, at the ribbon lap machine 24 there is a carrier or support rail 41 movable vertically up and down, and at the combing machines 37 there are carrier or support rails 42 movable vertically up and down. The transport rails 38 do not have bend portions effecting the change of direction of the circulation path or track. Instead, rail portions 39a, 39b, 39c, 39d, generally indicated by 39 are provided, each of which is pivotable about its related vertical axis 40. By means of the rail portions 39 a closed, endless circulation path or track is once again provided.
Laps 36 are lifted for transport in groups of three by means of the carrier or support rail 41. A table 44 can be provided as a lap transfer location. The three laps 36 lifted by the carrier rail 41 are brought via the transport rail 38a onto the rail portion 39a, while the latter rests in its illustrated location with its one end on the transport rail 38a leading from the ribbon lap machine 24. Then, the rail portion 39a is rotated through 90°, so that it is aligned with the rail portion 39b. Now, the three laps 36 are moved onto the rail portion 39b. If these laps 36 are intended for the lowest combing machine 37 shown in FIG. 3, then they are transported to its lap transfer location and deposited thereon.
If, however, this group of laps 36 is intended, for example, for the second lowest combing machine 37, then the rail portion 39b is rotated through 90° and the laps 36 are passed via the transport rail 38b to the rail portion 39c. From the location of the latter, they are fed to the second lowest combing machine 42 and deposited on the lap transfer location thereof.
It is noted with reference to the embodiments concerning the end 35 of the sheet according to FIGS. 1 and 2, that also in the embodiment according to FIG. 3 carriers or supports 15 of the type shown in FIG. 2 are used. These carriers 15 are again provided with a holder rod 32 which rests against the outermost end 35 of a lap 36 during transport thereof. It is clear that in the embodiment according to FIG. 3 through rotation of the rail portions 39 about their axes or pivots 40 in the one direction or in the opposite direction, the ends 35 of the sheets always can be brought to the required side, that is to the side on which they are subjected to a manipulation. In this embodiment this result is thus obtained by appropriate choice of the pivoting range of the rail portions, that is also through an appropriate construction of the transport system.
The return of empty tubes is effected via the transport rails 38 and rail portions 39 illustrated on the left-hand side of FIG. 3.
In the embodiment of FIG. 3 the laps 36 are delivered to the combing machines 37 in groups of three laps 41. It is clear that instead of this arrangement, there could be provided lap groups of four which are normal in practice, or also other lap group sizes. In such case, the rail portions 39, the carrier rail 41, the table 44 and the carrier rails 42 are advantageously arranged to receive respectively four carriers or an appropriate number of such carriers.
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. | A transport system for transporting laps wound on tubes in spinning preparation. The laps are transported above head height by carriers or supports movable along transport rails and are raised and lowered by means of carrier rails. The transport rails and the carrier rails are components or parts of a closed, endless circulation path or track. Each carrier has a holder for the lap and a holder for the empty tube. The invention provides the advantages that no special transport system is required for return of the tubes. Moreover, transport of individual laps or of a group of such laps is possible and an ordered and simple circulation path is provided during transport of these elements or parts. Furthermore, the system can readily be automated. | 3 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to a process for the preparation of pure aqueous solutions of betaines of the formula 1 ##STR1## in which R 1 is an alkyl radical having 6 to 22 carbon atoms, preferably 8 to 18 carbon atoms, or a radical of the formula R'CONH(CH 2 ) z --, in which R' is an alkyl radical having 5 to 21 carbon atoms, preferably having 5 to 17 carbon atoms, and z is 2, 3 or 4,
R 2 is an alkyl radical having 1 to 4 carbon atoms or a radical of the formula --(CH 2 ) m --OH, in which m is 1, 2 or 3,
R 3 is an alkyl radical having 1 to 4 carbon atoms or a radical of the formula --(CH 2 ) m --OH mentioned and
y is 1, 2 or 3, by reaction of a tertiary amine of the formula 2
R.sup.1 --NR.sup.2 R.sup.3 ( 2)
in which R 1 , R 2 and R 3 have the meanings given, with an ω-halocarboxylic acid of the formula 3
X--(CH.sub.2).sub.y --COOH (3)
in which X is a halogen, preferably Cl, and y has the meaning given, and with an alkali metal hydroxide in the aqueous phase.
DESCRIPTION OF THE PRIOR ART
The preparation of aqueous solutions of betaines by reaction (quaternization) of tertiary amines with an ω-halocarboxylic acid and an alkali metal hydroxide in the aqueous phase has already been known for a long time, for example from the two U.S. Pat. Nos. 3,819,539 and 4,497,825. It is based on the following overall equation (the reaction components are dimethyllaurylamine, monochloroacetic acid and sodium hydroxide): ##STR2##
The resulting aqueous solutions essentially comprise the betaine required, the alkali metal halogen salt formed and the water employed and formed, and in general have an active compound content of 20 to 60% by weight, preferably 25 to 50% by weight. These aqueous betaine solutions are already valuable products as such (detergent bases), in particular in the field of body care. This is because, betaines have not only good cleansing properties but also a good skin tolerability.
In the preparation of the aqueous betaine solutions in question, it is a matter above all of obtaining the betaine in a high yield and high purity. In particular, the aqueous betaide solutions should be pure in respect of the starting amine and halocarboxylic acids (which is present as such and/or as the alkali metal salt), i.e. they should contain these compounds, if at all, only in a very small amount. Attempts have already often been made to achieve this aim by specific measures, thus, for example, by maintaining a particular pH during the quaternization, by bringing together the reaction components of tertiary amine, halocarboxylic acid and alkali metal hydroxide in a quite specific sequence, for example by initially introducing the tertiary amine and the halocarboxylic acid into the reaction vessel and slowly metering in the alkali metal hydroxide, or by initially introducing the halocarboxylic acid and the alkali metal hydroxide into the reaction vessel and metering in the tertiary amine, furthermore by using specific solvents and/or by maintaining a relatively low temperature during the reaction. All these attempts have not produced the desired success. The aqueous betaine solutions obtained by the known processes do not meet the purity requirements mentioned, which at the present time are becoming ever stricter.
SUMMARY OF THE INVENTION
The invention relates to a process for the preparation of pure aqueous solutions of betaines of the formula 1 ##STR3## in which R 1 is an alkyl radical having 6 to 22 carbon atoms, preferably 8 to 18 carbon atoms, or a radical of the formula R'CONH(CH 2 ) z --, in which R' is an alkyl radical having 5 to 21 carbon atoms, preferably having 5 to 17 carbon atoms, and z is 2, 3 or 4,
R 2 is an alkyl radical having 1 to 4 carbon atoms or a radical of the formula --(CH 2 ) m --OH, in which m is 1, 2 or 3,
R 3 is an alkyl radical having 1 to 4 carbon atoms or a radical of the formula --(CH 2 ) m --OH mentioned and
y is 1, 2or 3, by reaction of a tertiary amine of the formula 2
R.sup.1 --NR.sup.2 R.sup.3 ( 2)
in which R 1 , R 2 and R 3 have the meanings given, with an ω-halocarboxylic acid of the formula (3)
X--(CH.sub.2).sub.y --COOH (3)
in which X is a halogen, preferably Cl, and y has the meaning given, and with an alkali metal hydroxide in the aqueous phase.
The object of the invention accordingly comprises providing a process for the preparation of the above-mentioned aqueous betaine solutions which produces the betaines in a high yield and high purity, i.e. aqueous betaine solutions comprising less than 1.5% by weight of tertiary amine, preferably less than 0.5% by weight, and comprising less than 50 ppm of ω-monohalocarboxylic acid, preferably less than 10 ppm.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The invention relates to a process for the preparation of pure aqueous solutions of betaines of the formula 1 ##STR4## in which R 1 is an alkyl radical having 6 to 22 carbon atoms, preferably 8 to 18 carbon atoms, or a radical of the formula R'CONH(CH 2 ) z --, in which R' is an alkyl radical having 5 to 21 carbon atoms, preferably having 5 to 17 carbon atoms, and z is 2, 3 or 4,
R 2 is an alkyl radical having 1 to 4 carbon atoms or a radical of the formula --(CH 2 ) m OH, in which m is 1, 2 or 3,
R 3 is an alkyl radical having 1 to 4 carbon atoms or a radical of the formula --(CH 2 ) m OH mentioned and
y is 1, 2or 3, by reaction of a tertiary amine of the formula 2
R.sup.1 --NR.sup.2 R.sup.3 ( 2)
in which R 1 , R 2 and R 3 have the meanings given, with an ω-halocarboxylic acid of the formula (3)
X--(CH.sub.2).sub.y --COOH (3)
in which X is a halogen, preferably Cl, and y has the meaning given, and with an alkali metal hydroxide in the aqueous phase.
The process according to the invention comprises first reacting the tertiary amines, the ω-monohalocarboxylic acid and the alkali metal hydroxide in a molar ration of 1:1 to 1.5:1 to 1.8, preferably 1:1.03 to 1.3:1 to 1.5, at a temperature of 60° to 98° C., preferably 70° to 95° C., and then treating the resulting aqueous betaine solution with a sulfonating agent at a pH of 7.5 to 13, preferably 8 to 10, and a temperature of 60° to 98° C., preferably 70° to 95° C., in order to convert the ω-monohalocarboxylic acid present in the aqueous betaine solution into the ω-sulfocarboxylic acid.
The process according to the invention is thus based on the combination of two specific process steps. In the first process step, the starting components of tertiary amine, ω-monohalocarboxylic acid and alkali metal hydroxide are employed in a selected molar ratio and the reaction is in general carried out until the low content of starting amine mentioned is obtained, i.e. until less than 1.5% by weight of tertiary amine, preferably less than 0.5% by weight of tertiary amine, based on the tertiary amine employed, is present in the resulting aqueous betaine solution. The use according to the invention of equimolar or excess halocarboxylic acid, based on the tertiary amine, thus gives rise to a reaction product which comprises only very little tertiary starting amine, if any. The aqueous betaine solution obtained in the first reaction step is therefore pure in respect of tertiary amine. However, it comprises halocarboxylic acid, which is present as such and, in particular, in the form of an alkali metal salt (for simplicity, acid is referred to below). In order to free the aqueous betaine solution also from the halocarboxylic acid, it is treated according to the invention with a sulfonating agent. The ω-monohalocarboxylic acid is thereby converted into the corresponding sulfocarboxylic acid. The following equation is intended to illustrate this, the halocarboxylic acid being monochloroacetic acid and the sulfonating agent being sodium hydrogen sulfite (it is understood that the acids mentioned are present as alkali metal salts):
Cl--CH.sub.2 COOH+NaHSO.sub.3 →HSO.sub.3 --CH.sub.2 COOH+NaCl
In contrast to the ω-monohalocarboxylic acid (for example monochloroacetic acid), the sulfocarboxylic acid (sulfoacetic acid) is not a troublesome compound in the aqueous betaine solution, and in particular, in contrast to the ω-monohalocarboxylic acid, it is not toxic. After the sulfonation, an aqueous betaine solution is present which has the required purity both in respect of the tertiary amine and in respect of the halocarboxylic acid. It essentially comprises the betaine formed, the alkali metal halide and water and a greater or lesser amount of sulfocarboxylic acid in the form of an alkali metal salt, the betaine content (active compound content) being about 20 to 60% by weight, preferably about 25 to 50% by weight.
In the process according to the invention, the reaction between the tertiary amine and the ω-monohalocarboxylic acid in the presence of an alkali metal hydroxide and water is thus first carried out. The tertiary amine, the ω-monohalocarboxylic acid (which is in general employed in the form of a 60 to 80% strength by weight aqueous solution) and the alkali metal hydroxide (which is in general employed in the form of a 30 to 60% strength by weight aqueous solution, preferably 35 to 50% strength by weight aqueous solution) are employed in a molar ratio of 1:1.0 to 1.5:1.0 to 1.8, preferably in a molar ratio of 1:1.03 to 1.3:1.0 to 1.5. The amount of water (which is introduced as such and in the forte of the aqueous solutions of alkali metal hydroxide and halocarboxylic acid mentioned) is in general chosen such that the aqueous betaine solution obtained after the reaction has the abovementioned active compound content. The reaction temperature is 60° to 98° C., preferably 70° to 95° C. The reaction is in general maintained until no further tertiary starting amine is present in the aqueous betaine solution formed, or its content has fallen to the tolerated value. According to a preferred procedure, the tertiary amine and water in an amount such that a 15 to 55% strength by weight, preferably 20 to 45% strength by weight, aqueous solution of the tertiary amine in water is present are initially introduced into the reaction vessel. The mixture is heated to 60° to 98° C., preferably to 70° to 95° C. The ω-monohalocarboxylic acid and the alkali metal hydroxide are now added essentially simultaneously (continuously or in portions and separately from one another), in each case in the form of the aqueous solutions mentioned, while maintaining the temperature mentioned, after which the mixture is kept at this temperature for a further period until the required low amine content is reached. This reaction time is in general 5 to 30 hours. As regards the addition of halocarboxylic acid and alkali metal hydroxide, it has proved advantageous first to add the ω-halocarboxylic acid by itself and only to start addition of the alkali metal hydroxide when about 10 to 40 mol %, preferably about 15 to 30 mol %, of the ω-halocarboxylic acid has been added. Thus, after 10 to 40 mol %, preferably 15 to 30 mol %, of the total amount of ω-monohalocarboxylic acid to be employed has been introduced continuously or in portions into the amine/water mixture, which is heated to 60° to 98° C., preferably 70° to 95° C., the alkali metal hydroxide and the remaining halocarboxylic acid are added essentially simultaneously (continuously or in portions and separately from one another) at the temperature mentioned. After addition of the alkali metal hydroxide and halocarboxylic acid, the mixture is kept at 60° to 98° C., preferably 70° to 95° C. for an after-reaction, in general until the low values mentioned for the tertiary starting amine are reached. The aqueous betaine solution thus obtained is still contaminated to a greater or lesser degree with ω-monohalocarboxylic acid.
The betaine solution still contaminated with ω-monohalocarboxylic acid is now treated with a sulfonating agent at a pH of 7.5 to 13, preferably 8 to 11, in order to convert the ω-monohalocarboxylic acid present (which is present in the form of an alkali metal salt) into the corresponding sulfocarboxylic acid (sulfocarboxylic acid alkali metal salt). The pH mentioned, if it is not in any case already present, is established by addition of alkali metal hydroxide or acid (for example hydrochloric acid). For the sulfonation, the mixture is brought to a temperature of 60° to 98° C., preferably to 70° to 95° C. This temperature as a rule already exists at the conclusion of the first reaction step (the quaternization). The customary sulfonating agents can be employed for the sulfonation. Suitable sulfonating agents are thus gaseous SO 2 , H 2 SO 3 , alkali metal sulfite and alkali metal hydrogen sulfite, the alkali metal preferably being sodium or potassium. Of these sulfonating agents, the sulfites, pyrosulfites and bisulfites (hydrogen sulfites) are preferred and are in general employed in solid form or in the for of a 20 to 40% strength by weight aqueous solution. The amount of sulfonating agent, based on the amount of ω-monohalocarboxylic acid present, is as a rule 1 to 2.5 molar equivalents, preferably 1.3 to 2 molar equivalents. In detail, the sulfonation is preferably carried out such that the sulfonating agent is introduced all at once or continuously or in portions into the aqueous betaine solution, which is heated to 60° to 98° C., preferably 70° to 95° C., after which the solution is kept at the temperature mentioned until the desired low content of ω-monohalocarboxylic acid is reached. This reaction time is in general 1 to 4 hours. The product thus obtained is the aqueous betaine solution which is pure with respect to tertiary amine and monohalocarboxylic acid. If the sulfonating agent present as a result of an excess employed is undesirable, it can be oxidized, for example in the case of sulfite, with oxygen (air) or hydrogen peroxide to give the sulfate, and can thus be destroyed. After the oxidative treatment, an aqueous betaine solution which is also free from the sulfonating agent employed exists.
The following may also be noted in respect of the starting compounds of tertiary amine, ω-monohalocarboxylic acid and alkali metal hydroxide: the tertiary starting amines correspond to the abovementioned formula 2. The long alkyl radical R 1 can also contain double bonds, preferably 1 to 3. Preferred starting amines are those of the formula 2, if R 1 is an alkyl radical having 8 to 18 carbon atoms or a radical of the formula R'CONH(CH 2 ) z --, in which R' is an alkyl radical having 5 to 17 carbon atoms and z is 2, 3 or 4, and R 2 and R 3 are each methyl. Examples which may be mentioned are: dimethyloctylamine, dimethyllaurylaraine, dimethylstearylamine, dimethyl-coconut alkylamine, dimethyltallow alkylmine and the like, as well as lauroylaminopropyldimethylamine, stearoylaminopropyldimethylamine, coconut acylaminopropyldimethylamine and the like. The ω-halocarboxylic acid is preferably monochloroacetic acid. The alkali metal hydroxide is preferably sodium hydroxide or potassium hydroxide. The term "aqueous" betaine solution also comprises those solutions which also contain other solvents in addition to water, for example methanol, ethanol, propanol and/or isopropanol.
The process according to the invention has a number of advantages. It produces very pure aqueous betaine solutions. Betaine solutions which contain less than 0.5% by weight of tertiary amine (based on the amount of tertiary amine employed) and less than 50 ppm or even less than 10 ppm of ω-monohalocarboxylic acid can thus be obtained. The process according to the invention furthermore can also be carried out continuously, as well as discontinuously. The continuous procedure is preferably carried out in two to four stirred kettles arranged in cascade form.
The process according to the invention can thus be carried out discontinuously or continuously and produces betaine in a high yield and high purity.
The invention will now be illustrated in more detail by examples.
Example 1
188 g (0.587 mol) of coconut fatty acid amidopropyl-N,N-dimethylamine (based on hardened coconut fatty acid) and 345 g of water, i.e. 35% by weight of tertiary amine compound in water, are initially introduced into a 1 l glass flask fitted with a stirrer, thermometer, reflux condenser and dropping funnel. The mixture is heated to 82° C., while stirring. 72.8 g (0.616 mol) of an 80% strength by weight aqueous monochloroacetic acid (MCA) solution are slowly and continuously added dropwise to this suspension in the course of 5.5 hours. With a time delay of 30 minutes, after about 1/5 (20 mol %) of the total MCA solution has been added, 53.7 g (0.671 mol) of a 50% strength by weight aqueous NaOH solution are continuously added dropwise at the same time as the remaining MCA solution and separately therefrom (the molar ratio of tertiary amine compound, MCA and NaOH is 1:1.05:1.14). When the addition has ended, the mixture is allowed to after-react at 80° C. for 9 hours. The resulting 30% strength by weight aqueous betaine solution has a content of starting amidoamine of 0.14% by weight and of MCA of 0.13% by weight, i.e. 1300 ppm.
1.9 g (200 mol % or 2 molar equivalents, based on the residual MCA) of sodium bisulfite in the form of a 30% strength by weight aqueous solution are added to the resulting betaine solution, which has a pH of 10 to 11, at a temperature of 80° to 85° C., while stirring, after which the mixture is allowed to after-react at the temperature of 80° to 85° C. and at the pH of 10 to 11. After only 2 hours, an MCA content of less than only 5 ppm can be detected.
The aqueous betaine solution thus obtained, which is practically pure both in respect of starting amine and in respect of MCA, is brought to pH 5 with hydrochloric acid and stirred with 96 mol % of hydrogen peroxide (molar percentage based on the sodium bisulfite present) at 85° C. for 1 hour, in order to convert the excess sodium bisulfite into sodium sulfate. The desired pure aqueous 30% strength by weight betaine solution which is also free from sulfite is present.
Example 2
5.1 g (200 mol %, based on the MCA) of solid sodium sulfite (Na 2 SO 3 . 7H 2 O) are added to 800 g of a 30% strength by weight coconut amidopropyl-N,N-dimethylcarboxymethylammonium-betaine solution prepared analogously to Example 1 and having a starting amidoamine content of only 0.15% by weight and an MCA content of 0.12% by weight or 1200 ppm and a pH of 10 to 11, and the mixture is stirred at 90° to 95° C. for 2 hours. An aqueous 30% strength by weight betaine solution containing sodium sulfite but less than 5 ppm of MCA and 0.15% by weight of starting amidoamine is present.
Example 3
150 g (0.664 mol) of lauryldimethylamine (70% by weight of C 12 , 25% by weight of C 14 and 5% by weight of C 16 ) and 300 g of water, i.e. 33% by weight of tertiary amine compound in water, are initially introduced into a 1 l glass flask fitted with a stirrer, thermometer, reflux condenser and dropping funnel. The mixture is heated to 80° C., while stirring. 89.0 g (0.753 mol) of an 80% strength by weight aqueous monochloroacetic acid (MCA) solution are slowly and continuously added dropwise to this suspension in the course of 5.5 hours. With a time delay of 30 minutes, after about 1/5 (20 mol %) of the total MCA solution has been added, 66.0 g (0.825 mol) of a 50% strength by weight aqueous NaOH solution are continuously added dropwise at the same time as the remaining MCA solution and separately therefrom (the molar ratio of tertiary amine, MCA and NaOH is 1:1.13:1.24). When the addition has ended, the mixture is allowed to after-react at 80° C. for 10 hours. The resulting 30% strength by weight aqueous betaine solution has a content of starting amine (lauryldimethylamine) of 0.3% by weight, and of MCA of 0.2% by weight, i.e. 2000 ppm.
1.1 g (150 mol % or 1.5 molar equivalents, based on the residual MCA) of solid sodium pyrosulfite are added to the betaine solution obtained, which has a pH of 10 to 11, at a temperature of 80° to 85° C., while stirring, after which the mixture is allowed to after-react at the temperature of 80° to 85° C. and the pH of 10 to 11. After 4 hours, an MCA content of less than only 5 ppm is to be detected.
The aqueous betaine solution thus obtained, which is practically pure both in respect of the starting amine and in respect of MCA, is brought to pH 5 with hydrochloric acid and stirred with 96 mol % of hydrogen peroxide (molar percentages based on the sulfite present) for 1.5 hours at 85° C. in order to convert the excess sulfite into sulfate. The desired pure aqueous 30% strength by weight betaine solution which is also free from sulfite is present.
Examples 4 and 5
The corresponding betaine solutions are prepared analogously to Example 1 starting from octylamidopropyl-N,N-dimethylamine (Example 4) and laurylamidopropyl-N,N-dimethylamine (Example 5). The amount of residual MCA is brought to less than 5 ppm by reaction with sodium bisulfite as in Example 1.
Example 6
A 30% strength by weight betaine solution having a residual MCA content of 2000 ppm and a residual amine content of 0.3% by weight is prepared analogously to Example 3 starting from octyldimethylamine. A residual MCA content of less than 5 ppm is obtained by reaction with 2 molar equivalents of sodium sulfite, based on the residual MCA, as described in Example 3. | The process described relates to the preparation of aqueous betaine solutions by reaction of a tertiary amine with an ω-monohalocarboxylic acid, preferably monochloroacetic acid, and an alkali metal hydroxide in the presence of water, which solutions are said to be highly pure particularly in respect of the tertiary starting amine and ω-monohalocarboxylic acid. This is achieved by first reacting the three reaction components in a certain molar ratio with the aim of obtaining a betaine solution which comprises only a tolerated amount of starting amine. This aqueous betaine solution is then treated with a sulfonating agent, preferably with an alkali metal sulfite, alkali metal pyrosulfite or alkali metal bisulfite, for conversion of the ω-monohalocarboxylic acid present into the corresponding sulfocarboxylic acid, which is not troublesome. The process described is simple to carry out and leads to the highly pure aqueous betaine solutions mentioned. | 2 |
The present application is a Continuation Application of U.S. patent application Ser. No. 13/500,577, filed on Apr. 5, 2012, which is based on International Application No. PCT/JP2010/067277, filed on Oct. 1, 2010, which is based on the Japanese Patent Application No. 2009-233095, filed on Oct. 7, 2009, the entire contents of which are incorporated herein by reference.
TECHNICAL FIELD
The present invention is related to a computer system and a maintenance method of a computer system, and more particularly, to a computer system which it is possible to carry out maintain processing without stopping the operation of the system and a maintenance method.
BACKGROUND TECHNIQUE
In case to carry out maintenance processing to the components of a computer system, only a unit apparatus as a maintenance object must be separated from the system in order to prevent the stop of the function or the operation of the system. For example, by migrating the function of a server as the maintenance object to another server (e.g. the standby system server), the maintenance (for example, the update and repair of a file) of the server becomes possible without stopping a function.
In case of carrying out the maintenance of a unit, a method of separating the maintenance object from the system and a method of restoring the unit separated after the maintenance to the system are disclosed in JP 2007-304845 (Patent Literature 1), JP 2009-146106A (Patent Literature 2), JP 2006-285597A (Patent Literature 3), and JP 2008-118236A (Patent Literature 4).
Patent Literature 1 discloses a computer system which updates software on a standby system virtual hardware and after that, and reduces a service stopping time in the update of the software by taking over the processing of the operating system to the standby system.
Patent Literature 2 discloses a storage system which switches a physical port which is an addition destination of a virtual port to another physical port, updates a routing table of a switch unit based on identifier data of the physical port of the addition destination, and changes an access path to an identical storage unit. Thus, the change of an access path becomes possible without stopping a computer.
Patent Literature 3 discloses a storage system which sets an address to a storage which is added or exchanged based on address conversion data set in advance, to a switch.
Patent Literature 4 discloses a maintenance method which switches a reception destination of a packet for a virtual address to the software of a new version from the software of an old version by switching the address corresponding to the virtual address.
CITATION LIST
[Patent Literature 1] JP 2007-304845A
[Patent Literature 2] JP 2009-146106A
[Patent Literature 3] JP 2006-285597A
[Patent Literature 4] JP 2008-118236A
SUMMARY OF THE INVENTION
In the computer system described in Patent Literatures, management is separate carried out on the side of a network and the side of IT. Therefore, when maintaining a component (server and switch) in the system, the separation and restoration of a maintenance object unit and the setting for the maintenance are individually carried out on the side of the network and the side of the IT. However, because these processing has an influence on the operation of the system, it is desirable to integratedly manage both on the side of the network and the side of the IT to carry out the maintenance.
From the above, an object of the present invention is to provide a computer system which controls the side of network and the side of computer integratedly to make the maintenance possible without the stop of a function.
In order to solve the above-mentioned problem(s), the present invention uses the configuration described below.
A computer system of the present invention is provided with the switch to transfer a received packet data to a destination according to a flow set to itself, an integrated management apparatus which specifies a maintenance object unit and a controller. The controller separates the maintenance object unit from the computer system by controlling the setting or deletion of the flow to the switch.
The maintenance method of the present invention is executed by a computer system which is provided with a physical server connected through a switch which transfers the received packet data to the destination according to the flow set to itself. In the maintenance method of the present invention, an integrated management apparatus specifies a maintenance object unit and a controller separates the maintenance object unit from the computer system by controlling the setting or deletion of the flow to the switch.
According to the present invention, by controlling the side of the network and the side of the computer integratedly, the maintenance of the computer system can be executed without stopping the function.
BRIEF DESCRIPTION OF THE DRAWINGS
The object, effect, feature of the above invention and would become clearer from description of the following exemplary embodiments in cooperate with the attached drawing:
FIG. 1 is a diagram showing a configuration of a computer system according to exemplary embodiments of the present invention;
FIG. 2 is a diagram showing a configuration of a VM management equipment of the present invention;
FIG. 3 is a diagram showing a configuration of an open flow controller of the present invention;
FIG. 4 is a diagram showing an example of a configuration of a flow table retained by the open flow controller of the present invention;
FIG. 5 is a diagram showing an example of topology data retained by the open flow controller of the present invention;
FIG. 6 is a diagram showing an example of communication route data retained by the open flow controller of the present invention;
FIG. 7 is a diagram showing a configuration of an open flow switch according to the present invention;
FIG. 8 is a diagram showing an example of a flow table retained by a switch of the present invention;
FIG. 9 is a diagram to showing the open flow control according to the present invention;
FIG. 10 is a sequence diagram showing maintenance processing operation (maintenance to an operating system server) in a first exemplary embodiment;
FIG. 11 is a sequence diagram showing the maintenance processing operation (system switching after the maintenance to the operating system server) of the first exemplary embodiment;
FIG. 12 is a sequence diagram showing start processing operation (system switching) after the maintenance processing by a server according to the present invention;
FIG. 13 is a sequence diagram showing the start processing operation (system switched) after the maintenance processing by the server according to the present invention;
FIG. 14 is a sequence diagram showing the maintenance processing operation (maintenance to a standby system server) of the first exemplary embodiment;
FIG. 15 is a sequence diagram showing the maintenance processing operation (maintenance to a load distribution system server) of the first exemplary embodiment;
FIG. 16 is a sequence diagram showing the start processing operation after the maintenance processing by the load distribution system server according to the present invention;
FIG. 17 is a sequence diagram showing shutdown processing operation to an independent server (no VMM operation) of the first exemplary embodiment;
FIG. 18A is a sequence diagram showing the preparation processing operation of the maintenance processing to the independent server (VMM operation) of the first exemplary embodiment;
FIG. 18B is a sequence diagram showing the preparation processing operation of the maintenance processing to the independent server (VMM operation) of the first exemplary embodiment;
FIG. 19 is a sequence diagram showing the maintenance processing operation after migration of a virtual machine in the first exemplary embodiment;
FIG. 20 is a sequence diagram showing the maintenance processing operation to the switch of a second exemplary embodiment;
FIG. 21 is a flow chart showing detour verification processing operation in case of the maintenance processing in the second exemplary embodiment;
FIG. 22 is a sequence diagram showing the start processing operation of a switch in case of the maintenance processing in the second exemplary embodiment;
FIG. 23A is a sequence diagram showing the maintenance processing operation to the switch in a third exemplary embodiment;
FIG. 23B is a sequence diagram showing the maintenance processing operation to the switch in the third exemplary embodiment;
FIG. 24A are a flow chart showing endpoint change processing operation for the detour route generation in case of the maintenance processing to the switch;
FIG. 24B is a flow chart showing the endpoint change processing operation for the detour route generation in case of the maintenance processing to the switch;
FIG. 25A is a flow chart showing the endpoint restoration processing operation after the maintenance processing to the switch;
FIG. 25B is a flow chart showing the endpoint recovery processing operation after the maintenance processing to the switch;
FIG. 26A is a sequence diagram showing the maintenance processing operation (maintenance to the operating system server) of a fourth exemplary embodiment;
FIG. 26B is a sequence diagram showing the maintenance processing operation (maintenance to the operating system server) of the fourth exemplary embodiment;
FIG. 27A is a sequence diagram showing the start processing operation after the maintenance processing by the server according to the fourth exemplary embodiment;
FIG. 27B is a sequence diagram showing the start processing operation after the maintenance processing by the server according to the fourth exemplary embodiment;
FIG. 28 is a sequence diagram showing the migration preparation processing operation in the first exemplary embodiment in case of the migration processing by the virtual machine;
FIG. 29 is a sequence diagram showing the memory image transferring processing in the first and second implementation examples in case of the migration processing by the virtual machine;
FIG. 30 is a sequence diagram showing the access destination switching processing in the first implementation example in case of migration processing by the virtual machine;
FIG. 31 is a sequence diagram showing the migration preparation processing in the second implementation example in case of migration processing by the virtual machine; and
FIG. 32 is a sequence diagram showing the access destination switching processing in the second implementation example in case of migration processing by the virtual machine.
DESCRIPTION OF EXEMPLARY EMBODIMENTS
Hereinafter, exemplary embodiments of the present invention will be described with reference to the attached drawings. In the drawings, same reference numerals are assigned to same components.
(Configuration of the Computer System)
Referring to FIG. 1 to FIG. 9 , the configuration of a computer system of the present invention will be described. FIG. 1 is a diagram showing a configuration of the computer system of the present invention. The computer system of the present invention is provided with an integrated management apparatus 1 , a virtual machine management apparatus 2 (hereinafter, to be referred to as a VM management apparatus 2 ), an open flow controller 3 (hereinafter, to be referred to as an OFC 3 ), a server management apparatus 4 , switches 41 to 44 (hereinafter, to be referred to as open flow switches (OFSs) 41 to 44 ), physical servers 5 and 6 , and a storage unit 7 (ex. shared disk). Also, the computer system of the present invention may be provided with a load balancer 9 . The number of OFSs 41 to 44 is not limited to four in case of FIG. 1 . When the OFSs 41 to 44 are distinguished from each other, the OFSs 41 to 44 are totally referred to as an OFS 4 i.
The physical servers 5 and 6 are mutually connected through the OFS 4 i . Also, the physical servers 5 and 6 are connected with an external network exemplified by the Internet through the OFS 4 i . It should be noted that in the present exemplary embodiment, the two physical servers 5 and 6 are exemplified but the number of physical servers is not limited to this.
Each of the physical servers 5 and 6 is a computer unit which is provided with a CPU and a RAM. By executing a program which is stored commonly or separately in the storage unit 7 , at least one virtual machine is realized. In detail, the physical server 5 is provided with virtual machines 101 to 10 n (n is a natural number) which are realized by dividing a use region of a CPU (not shown) and the storage unit 7 in a logic division or physical division. Or, the virtual machines 101 to 10 n may be realized in a guest operating system (GOS) which is emulated on a host operating system (HOS) or in a software program which operates on the GOS. The virtual machines 101 to 10 n are managed by the virtual machine monitor 10 (hereinafter, to be referred to as a VMM 10 ) which is realized by executing a program stored in the storage unit 7 by the CPU (not shown). At least one of the virtual machines 201 to 20 m (m is a natural number) is implemented on the physical server 6 , and managed by a VMM 20 , like the physical server 5 .
It is desirable that disk images (memory images) which are used by the virtual machines 101 to 10 n and 201 to 20 m are stored in a shared disk. For example, the shared disk is exemplified by a disk array which is connected by FC (Fiber Channel) or Ether (registered trademark), and so on, NAS (Network Attached storage), a database server and so on.
A method of managing the virtual machines 101 to 10 n by the VMM 10 and a method of managing the virtual machines 201 to 20 m by the VMM 20 are same as in a conventional example. For example, the VMM 10 manages the memory images used by the virtual machines 101 to 10 n , and the VMM 20 manages the memory images used by the virtual machines 201 to 20 m.
The virtual machines 101 to 10 n transmit and receive to and from another unit (for example, a computer unit on an external network 8 or a virtual machine in another physical server 6 ) through a virtual switch 11 and a physical NIC (not shown) which are managed by the VMM 10 . In the present exemplary embodiment, the packet transmission based on TCP/IP (Transmission Control Protocol/Internet Protocol) is carried out as an example. In the same way, the virtual machines 201 to 20 m transmit and receive to and from another unit through a virtual switch 21 . Also, the communication between the virtual machines in the identical physical server is carried out through the virtual switch 11 or 21 .
It is supposed that in the virtual machines 101 to 10 n and 201 to 20 m according to the present invention, a MAC address does not change even if the virtual machine itself migrates to a VMM other than the VMM to which the virtual machine belongs or a physical server. Also, the virtual switches 11 and 21 may be controlled based on an open flow technique to be described later, and may carry out a switching operation as in the conventional layer 2 switch (L2 switch). However, the virtual switches 11 and 21 in the exemplary embodiments to be described below will be described as ones corresponding to the open flow. Moreover, a bridge connection is attained between the virtual machines 101 to 10 n and 201 to 20 m and the physical servers. That is, it is possible to carry out a direct communication from the outside by use of the MAC addresses and IP addresses of the virtual machines 101 to 10 n and 201 to 20 m.
It is desirable that a clustering mechanism 100 (not shown in FIG. 1 ) is installed into one of the physical servers 5 and 6 . The clustering mechanism 100 may operate as a common virtual machine on the physical servers 5 and 6 . The clustering mechanism 100 sets a cluster (use condition) of each of the physical servers 5 and 6 provided for the computer system to either of a HA (High Availability) cluster, a load distribution cluster, or an independent server. Also, the physical server set as the HA cluster is set to one of the operating system and the standby system. The physical server set as the HA cluster (operating system) functions as a physical server which operates in the computer system, and the physical server set as the HA cluster (standby system) becomes a standby state. Also, when being set as the load distribution cluster, a load is distributed to the physical servers by the load balancer 9 .
The VM management apparatus 2 manages the virtual machines 101 to 10 n and 201 to 20 m which operate on the physical servers 5 and 6 . FIG. 2 is a diagram showing the configuration of the VM management apparatus 2 of the present invention. It is desirable that the VM management apparatus 2 is realized by a computer which is provided with a CPU and a storage unit. In the VM management apparatus 2 , by executing a program stored in the storage unit by the CPU (not shown), functions of a VM migration control section 321 , a VMM managing section 322 , and a maintenance control unit 326 shown in FIG. 2 are realized.
The VM migration control section 321 controls the migration of a virtual machine. In detail, the VM migration control section 321 specifies a migration object virtual machine and a migration destination virtual machine monitor based on VMM management data 323 which is stored in the storage unit, and instructs the virtual machine monitors of a migration source and a migration destination to carry out the migration of the virtual machine. Thus, the migration of the virtual machine is executed between the instructed virtual machine monitors.
The VMM managing section 322 manages data (VMM management data 323 ) of the virtual machine monitor and the virtual switch under the management. The VMM management data 323 is provided with data (VMM data 324 ) of the virtual machines managed by the virtual machine monitor and an identifier of the virtual machine monitor, and data (VSW data 325 ) of an identifier of the virtual switch, and virtual machines connected with the virtual switch. It is desirable that the VMM data 324 and the VSW data 325 can be related and stored every virtual machine monitor which manages the virtual switches.
The VMM management data 323 may be stored in the storage unit in advance and may be acquired at an optional time or periodically from the VMMs 10 and 20 . When acquiring the VMM management data 323 from the VMM 10 or 20 , it is desirable that the VMM management data 323 is acquired from the VMM 10 or 20 in response to an instruction from the VMM managing section 322 , and the VMM management data 323 in the storage unit is updated based on the acquired data. Thus, it becomes possible to monitor the migration destination of the virtual machine and the connection destination of the virtual switch which are changed after the migration of the virtual machine.
The maintenance control section 326 controls maintenance processing to the physical servers 5 and 6 in response to a maintenance instruction from the server management apparatus 4 . In detail, the maintenance control section 326 controls the start and stop (shutdown) of the physical servers 5 and 6 in response to the maintenance instruction from the server management apparatus 4 , and transfers an update file and a patch of software (e.g. a guest OS) and OS transmitted from the server management apparatus 4 to the physical server of the maintenance object. The physical servers 5 and 6 update (version up and repair) the virtual machine (guest OS) and a host OS based on the update file transmitted from the maintenance control section 326 .
The OFC 3 controls communication in the system by the open flow technique. The open flow technique is a technique that a controller (OFC 3 in this example) sets route data in units of flows and data of multi-layer to the switches based on routing policy (flow: rule+action) and carries out a routing control and a node control. Thus, a routing control function is separated from routers and the switches, and the selection of optimal routing and the traffic management become possible through the centralized control by the controller. The switches (OFS 4 i ) to which the open flow technique is applied handle a communication not in units of packets or frames but as a flow of END2END, unlike the conventional router and switch.
In detail, the OFC 3 controls the operations (for example, a relay operation of packet data) of the switch or node by setting a flow (rule+action) every switch or node. In this case, the switch which is controlled by the OFC 3 is exemplified by the OFS 4 i , the virtual switches 11 and 21 and so on. The node which is controlled by the OFC 3 is exemplified by the virtual machines 101 to 10 n and 201 to 20 m , the VMMs 10 and 20 , the physical servers 5 and 6 , the storage unit 7 and so on.
FIG. 3 is a diagram showing the configuration of the OFC 3 of the present invention. It is desirable that the OFC 3 is realized by a computer which is provided with a CPU and a storage unit. By executing the program stored in the storage unit by the CPU (not shown) in the OFC 3 , each function of a switch control section 331 , a flow managing section 332 , a flow generating section 333 which are shown in FIG. 3 is realized.
Therefore, the switch control section 331 carries out the setting or deletion of a flow (rule+action) every switch and node according to a flow table 334 . The switch and the node according to the present invention refer to the set flow and execute an action (for example, relay or discard of packet data) corresponding to a rule according to header data of a reception packet. The rule and the action will be described in detail later.
FIG. 4 is a diagram showing an example of the configuration of the flow table 334 retained by the OFC 3 of the present invention. Referring to FIG. 4 , a flow identifier 441 for specifying a flow, an identifier (object unit 442 ), route data 443 , a rule 444 , action data 445 , and setting data 446 for identifying the set object (switch and node) of the flow are related to each other and set in the flow table 334 . A flow (rule 444 +action data 445 ) to all the switches and nodes which become the control objects of the OFC 3 is set to the flow table 334 . The method of handling communication such as QoS every flow and the data of the coding may be defined by the flow table 334 .
In the rule 444 , for example, a combination of an address for the layer 1 to layer 4 and an identifier in the OSI (Open Systems Interconnection) reference model which are contained in the header data of the packet data of TCP/IP are prescribed. For example, a combination of a physical port of the layer 1 shown in FIG. 9 , a MAC address of layer 2, an IP address of layer 3, a port number of layer 4, a VLAN tag is set as the rule 444 . A predetermined range of the identifiers and addresses such as the port number set to the rule 444 may be set. Also, it is desirable to distinguish the addresses of the destination and source and to be set as the rule 444 . For example, a range of the MAC destination address, a range of an address port number which specifies an application of a connection destination, a range of a source port number which specifies an application of a connection source are set as the rule 444 . Moreover, an identifier which specifies a data transfer protocol may be set as the rule 444 .
For example, a method of processing packet data of TCP/IP is prescribed in the action data 445 . For example, the data showing whether or not to relay reception packet data, and a transmission destination when to be relayed, are set. Also, a replica of the packet data and data which instructs to discard may be set to the action data 445 .
The route data 443 is data which specifies a route which applies a flow (rule 444 +action data 445 ). This is an identifier which is related to communication route data 336 to be described later.
The setting data 446 is data showing whether or not a flow (rule 444 +action data 445 ) has been set currently. Because the setting data 446 is related to the object unit 442 and the route data 443 , it is possible to confirm whether or not a flow has been set to the communication route, and it is possible to confirm whether a flow has been set every switch and node on the communication route. Also, the setting data 446 contains data showing whether a generated flow is in a usable (valid) condition or in non-usable (invalid) condition. The OFC 3 refers to the setting data 446 , sets only a valid flow to the OFS and does not set an invalid flow.
The flow managing section 332 refers to the flow table 334 to extract a flow (rule 444 +action data 445 ) corresponding to the header data of the first packet notified from the switch and node, and notifies to the switch control section 331 . Also, the flow managing section 332 adds a flow identifier 441 to the flow (rule 444 +action data 445 ) which is generated by the flow generating section 333 and stores in the storage unit. At this time, an identifier (route data 443 ) of a communication route to which a flow is applied, and an identifier (object unit 442 ) of the switch and node to which a flow is applied are assigned and added to the flow (rule 444 +action data 445 ) and are stored.
The flow generating section 333 calculates a communication route by using the topology data 335 , stores the calculation result as the communication route data 336 in the storage unit. Here, nodes as endpoints of a communication route (transmission source and destination of a packet), and switches and nodes on the communication route are set. For example, the flow generating section 333 specifies the nodes as the endpoints in the topology, extracts the shortest route between the endpoints by the Dijkstra method and outputs it as a communication route. Also, the flow generating section 333 sets a flow (rule 444 +action data 445 ) to set to the switches and the nodes on the communication route based on the communication route data 336 .
The topology data 335 contains data of a connection situation of the switch (for example, OFS 4 i , virtual switches 11 and 21 , and so on), the node (for example, virtual machines 101 to 10 n and 201 to 20 m , VMMs 10 and 20 , physical servers 5 and 6 , storage unit 7 , and so on), and an external network 8 (e.g. the Internet). Specifically, a port count 452 of a unit and port connection data 453 are related to a unit identifier 451 which specifies a switch and a node (unit) and are stored in the storage unit as the topology data 335 . The port connection data 453 contains a connection type which specifies a connection end (switch, node/external network) and data which specifies a connection destination (a switch ID in case of the switch, MAC address in case of the node, an external network ID in case of the external network).
The communication route data 336 is data for specifying a communication route. In detail, as the communication route data 336 , a node group (e.g. the virtual machines 101 to 10 n , and 201 to 20 m , the VMMs 10 and 20 , the physical servers 5 and 6 , the storage unit 7 and so on), endpoint data 461 which specifies an external network interface as an endpoint, passage switch data 462 which specifies a pair group of a passage switch (for example, the OFS 4 i , the virtual switches 11 and 21 and so on) and the port, and accompaniment data 463 are related to each other and stored in the storage unit. For example, when the communication route is a route connecting an external network and a node, an external network ID and a MAC address of the node are stored as endpoint data 461 . Or, when the communication route is a route connecting between nodes, a pair of MAC addresses of the nodes as both endpoints is stored as the endpoint data 461 . The passage switch data 462 contains an identifier of a switch (open flow switch and the virtual switch) which is provided on the communication route between the endpoints shown by the endpoint data 461 . Also, the passage switch data 462 may contain data for relating a flow (rule 444 +action data 445 ) set to a switch and the switch. The accompaniment data 463 contains data of a switch (passage switch) on the route after the endpoint is changed.
The flow managing section 332 of the present invention controls the flow generating section 333 in response to a migration instruction (migration preparation instruction) of the virtual machine to generate a flow (memory image transfer flow) for transferring the memory images and controls the switch control section 331 to set the memory image transfer flow to OFSs and nodes on a memory image transfer route. Also, the flow managing section 332 of the present invention controls the flow generating section 333 in response to the migration instruction (migration preparation instruction) of the virtual machines to generate an access flow (communication flow for migration destination VM) to a virtual machine after the migration, and controls the switch control section 331 to set the communication flow for the migration destination VM to the OFSs and the nodes on the communication route for the migration destination VM.
FIG. 7 is a diagram showing a configuration of the OFS 4 i according to the present invention. The OFS 4 i determines a method (action) of processing a reception packet according to the flow table 343 set by the OFC 3 . The OFS 4 i is provided with a transferring section 341 and a flow managing section 342 . The transferring section 341 and the flow managing section 342 may be configured in hardware and may be realized in software which is executed by a CPU.
The flow table 343 as shown in FIG. 8 is set in a storage unit of the OFS 4 i . The flow managing section 342 sets a flow (rule 444 +action data 445 ) which is acquired from the OFC 3 , to the flow table 343 . Also, when the header data of a reception packet received by transferring section 341 matches (coincides) with the rule 444 which is stored in the flow table 343 , the flow managing section 342 notifies the action data 445 corresponding to the rule 444 to the transferring section 341 . On the other hand, when the header data of the reception packet which is received by the transferring section 341 does not match (coincide) with the rule 444 which is stored in the flow table 343 , the flow managing section 342 notifies the reception of the first packet to the OFC 3 and transmits the header data to the OFC 3 .
The transferring section 341 carries out transfer processing according to the header data of the reception packet. In detail, the transferring section 341 extracts header data from the reception packet data and notifies to the flow managing section 342 . When receiving the action data 445 from the flow managing section 342 , the transferring section 341 carries out processing according to the action data 445 . For example, the transferring section 341 transfers the reception packet data to a destination node shown in the action data 445 . Also, when packet data which does not match the rule 444 which is prescribed in the flow table 343 is received, the transferring section 341 retains the packet data for a predetermined period and waits until a flow is set (flow table 343 is updated) from the OFC 3 .
Specifically, n operation of the OFS 4 i to which a flow is set in which the rule 444 : a MAC source address (L2) is “A 1 to A 3 ”, IP destination address (L3) is “B 1 to B 3 ”, protocol is “TCP”, and destination port number (L4) is “C 1 to C 3 ”, and the action data 445 : “relay to the virtual machine 101 of the physical server 5 ” are related to each other will be described. When receiving the packet data of the MAC source address (L2) of “A 1 ”, the IP destination address (L3) of “B 2 ”, the protocol of “TCP”, and the destination port number (L4) of “C 3 ”, the OFS 4 i determines that the header data matches to the rule 444 , and transfers the reception packet data to the virtual machine 101 . On the other hand, when receiving the packet data of the MAC source address (L2) of “A 5 ”, the IP destination address (L3) of “B 2 ”, the protocol of “TCP”, and the destination port number (L4) of “C 4 ”, the OFS 4 i determines that the header data does not matches to the rule 444 , notifies reception of the first packet to the OFC 3 , and transmits the header data to the OFC 3 . The OFC 3 extracts the flow (rule 444 +action data 445 ) corresponding to the received header data from the flow table 334 and transmits it to the OFS 4 i . It should be noted that when there is not an appropriate flow in the flow table 334 , the flow may be generated newly. The OFS 4 i sets the transmitted flow to its own flow table 343 and carries out relay processing of the reception packet according to this.
Generally, the OFS 4 i using the open flow technique issues a flow setting request to the OFC 3 when receiving the packet data (first packet) which does not correspond to the rule 444 set to its own flow table 343 . The OFC 3 sets a new flow to the OFS 4 i in response to this. When receiving the packet data according to the rule 444 , the OFS 4 i carries out the processing according to the set flow.
As described above, the open flow technique (also called programmable flow technique) is applied to a computer system of the present invention. It should be noted that in addition to the OFS 4 i , the virtual switches 11 and 21 , may be provided with the flow table in which a flow is set by the OFC 3 like the OFS 4 i . In this case, the OFC 3 can control the operations of the virtual switches 11 and 21 , like the OFS 4 i.
The server management apparatus 4 controls the clustering of the physical servers 5 and 6 by controlling the clustering mechanism 100 . It is desirable that the server management apparatus 4 is realized by a computer which is provided with a CPU and a storage unit. The server management apparatus 4 has a function of carrying out the maintenance processing to the physical servers 5 and 6 . In detail, the server management apparatus 4 has a function of controlling the start and shutdown of the physical servers 5 and 6 and has the update file and a patch of an OS and software operating on the physical servers 5 and 6 . The physical servers 5 and 6 update (version up and repair) the OS and software by the update file transmitted from the server management apparatus 4 .
The load balancer 9 is provided between the external network 8 and the OFS 4 i and carries out load distribution to the VMs 101 to 10 n and 201 to 20 m , and the physical servers 5 and 6 . Also, the load balancer 9 carries out the load distribution to the physical server (host OS) set to each virtual machine (guest OS) or the load distribution cluster in response to the instruction from the server management apparatus 4 . At this time, the assignment of processing (load) is carried out to each of physical servers and so on.
The computer system of the present invention is provided with the integrated management apparatus 1 which integratedly controls the VM management apparatus 2 , the OFC 3 , and the server management apparatus 4 . It is desirable that the integrated management apparatus 1 is realized by a computer system which is provided with a CPU and a storage unit. It is desirable that the integrated management apparatus 1 is provided with an input unit (e.g. a keyboard, a mouse), and a display (e.g. a monitor, a printer) which visibly displays various kinds of data transmitted from the VM management apparatus 2 , the OFC 3 or the server management apparatus 4 . The user (manager) controls the VM management apparatus 2 , the OFC 3 and the server management apparatus 4 by using the integrated management apparatus 1 , and executes the maintenance processing of the computer system.
The integrated management apparatus 1 , the VM management apparatus 2 , the OFC 3 and the server management apparatus 4 may be configured from a same computer system or different computer systems.
Hereinafter, the details of the operation of the maintenance processing which is executed by the above computer system will be described. The maintenance processing to the physical server or the virtual server in the first exemplary embodiment and the maintenance processing to switch (OFS) in the second to fourth exemplary embodiments will be described. Also, as the maintenance processing, the update of the file and an operation stop (maintenance processing such as the hardware exchange after shutdown) will be described as an example.
First Exemplary Embodiment
Referring to FIG. 10 to FIG. 19 , the maintenance processing operation to the physical server or the virtual server of the present invention will be described. In the present invention, after isolating (separating) the server and the virtual machine as the maintenance object from the system, the maintenance processing is carried out to the server. At this time, a method of isolating from the system according to whether the cluster and the maintenance object set to the server is the physical server or the virtual server, and a method of restoring after the maintenance processing are different. The maintenance processing will be described in the following four cases: when the maintenance object server is (1) HA cluster (operating system), (2) HA cluster (standby system), (3) a part of a load distribution cluster, and (4) an independent server. It should be noted that because a method of carrying out the maintenance processing to the virtual server (guest OS) is same as in (4) the independent server, the detailed description is omitted.
(1) Maintenance Processing to Server of HA Cluster
(Operating System)
Referring to FIG. 10 to FIG. 13 , the maintenance processing to the server set to the HA cluster (operating system) will be described. A case where the physical server 5 as the maintenance object is set to be the HA cluster (operating system) will be described.
FIG. 10 is a sequence diagram showing the maintenance processing (maintenance processing to the operating system server) of the first exemplary embodiment. Referring to FIG. 10 , the update (e.g. upgrade of OS) of a file to the physical server 5 of the HA cluster (operating system) will be described. First, the manager operates the integrated management apparatus 1 , specifies the server as a maintenance object (file updating object in this example) and instructs the separation of the maintenance object server. The integrated management apparatus 1 specifies the server as the maintenance object, and requests situation data (cluster configuration) of the server which is specified by the manager, to the server management apparatus 4 (Step S 601 ). Here, the physical server 5 is supposed to be specified as the maintenance object. Hereinafter, the specified server is referred to as a maintenance object server 5 .
The server management apparatus 4 searches configuration data (not shown) which contains the clustering and the operation situation of the server and which is retained by itself, extracts data (clustering data) which specifies the cluster which has been set to the maintenance object server 5 , and transmits the extracted data to the integrated management apparatus 1 (Steps S 602 and S 603 ). Here, the clustering data showing that the maintenance object server 5 has been set to the HA cluster (operating system) is transmitted.
When detecting that the maintenance object server 5 is the HA cluster (operating system), the integrated management apparatus 1 shifts to system switching processing. In detail, when detecting that the maintenance object server 5 is the HA cluster (operating system), the integrated management apparatus 1 instructs the server management apparatus 4 to switch the system of the HA cluster (Step S 604 ). The server management apparatus 4 instructs the switching of the operating system to the clustering mechanism 100 of the maintenance object server 5 (Step S 605 ). The clustering mechanism 100 of the maintenance object server 5 upgrades the server of the standby system to the operating system and the server of the operating system (maintenance object server 5 in this example) is downgraded to the standby system (Step S 606 ). The clustering mechanism 100 transmits a system switching completion report to the integrated management apparatus 1 through the server management apparatus 4 (Steps S 607 and S 608 ).
When the system switching is completed, the control procedure shifts to the maintenance processing (file update in this example). The integrated management apparatus 1 specifies the physical server 5 as the maintenance object server and instructs the server management apparatus 4 to carry out the maintenance processing (file update in this example) (Step S 609 ). The server management apparatus 4 transmits the update file to the maintenance object server 5 and issues a file update instruction (Step S 610 ). The physical server 5 updates its own software based on the update file which is received in response to the file update instruction (Step S 611 ). The server management apparatus 4 transmits the software update completion report of the physical server 5 to the integrated management apparatus 1 when confirming the file update completion in the physical server 5 . The integrated management apparatus 1 displays the file update completion to the maintenance object server 5 . Thus, the manager can confirm a normal end of the file update to the specified server. It should be noted that the system switched at the step S 606 may be automatically returned to the original condition (clustering configuration) after the file update processing is completed at the step S 611 .
The integrated management apparatus 1 stores the maintenance condition every physical server when receiving a maintenance completion report from the server management apparatus 4 or after a maintenance processing instruction is issued (Step S 612 ). Here, as the maintenance condition, the data showing that the physical server 5 is during the file update, and data (for example, the version data of the software and OS) of the file update completion and the updated file are stored. It should be noted that when the maintenance processing is the file update, the processing of the step S 612 may be omitted.
FIG. 11 is a sequence diagram showing the operation of the maintenance processing (system switching after the maintenance processing to the operating system server) in the first exemplary embodiment. Referring to FIG. 11 , when confirming the file update of the physical server 5 , the server management apparatus 4 instructs the switching of the operating system to the clustering mechanism 100 of the maintenance object server 5 (Step S 621 ). The clustering mechanism 100 of the maintenance object server 5 upgrades the standby system server (maintenance object server 5 in this example) to the operating system and the operating system server is downgraded to the standby system (Step S 622 ). The clustering mechanism 100 notifies the system switching completion to the integrated management apparatus 1 through the server management apparatus 4 (Steps S 623 and S 624 ).
Next, referring to FIG. 10 , the shutdown processing of the physical server 5 which is carried out to maintain the hardware or software of the physical server 5 of the HA cluster (operating system) will be described. Because the maintenance object server 5 is the HA cluster (operating system), the processing of the steps S 601 to S 608 shown in FIG. 10 is carried out and the switching between the operating system and the standby system is carried out, like the above-mentioned file update processing.
When the system switching is completed, the control flow shifts to the maintenance processing (operation shutdown processing in this example). The integrated management apparatus 1 specifies the physical server 5 as the maintenance object server and instructs the maintenance processing (operation shutdown processing in this example) (Step S 609 ). The server management apparatus 4 issues an operation shutdown instruction to the maintenance object server (Step S 610 ). The physical server 5 stops the operation (carries out the operation shutdown) in response to the operation shutdown instruction (Step S 611 ). The server management apparatus 4 transmits the operation shutdown completion report to the integrated management apparatus 1 when confirming the operation shutdown of the physical server 5 . The integrated management apparatus 1 displays that the maintenance object server 5 carried out the operation shutdown. Thus, the manager can confirm the operation shutdown of the specified server.
After issuing the maintenance processing instruction or when receiving a maintenance processing completion report from the server management apparatus 4 , the integrated management apparatus 1 stores the condition every physical server (Step S 612 ). In this case, it is desirable that the data showing the operation condition of the maintenance object server 5 (e.g. operation shutdown), the data showing whether or not the maintenance object server 5 is during the maintenance processing, and the data of the clustering set to the maintenance object server 5 are stored. For example, to be the HA cluster (standby system) which the physical server 5 maintains (operation shutdown) is stored. Also, the data of the clustering may contain the data showing the current condition (standby system) after being switched at the step S 606 and the condition (operating system) before the switching.
A serviceman carries out the maintenance processing (ex. exchange and addition of the hardware, replacement of software, and so on) of the physical server 5 which carried out the operation shutdown. When the maintenance processing to the physical server 5 is completed, the manager inputs a maintenance completion instruction to the integrated management apparatus 1 . At this time, the server that maintenance processing is completed is specified by the integrated management apparatus 1 . The integrated management apparatus 1 starts the physical server 5 which carried out the operation shutdown for the maintenance processing in response to the maintenance completion instruction.
FIG. 12 is a sequence diagram showing the operation of the start processing (system switching) after the maintenance processing of the server according to the present invention. Referring to FIG. 12 , the details of the start processing of the server after the maintenance processing will be described. In response to the maintenance completion instruction (server specification) by the manager, the integrated management apparatus 1 acquires the condition of the server which is specified by the manager from a list of maintaining servers (Step S 631 ). Here, the condition showing that the physical server 5 is the HA cluster (standby system) during operation shutdown (maintaining) is acquired. The integrated management apparatus 1 instructs the start of the specified server (physical server 5 in which maintenance processing is completed) (Step S 632 ). The server management apparatus 4 starts the specified physical server 5 (Steps S 633 and S 634 ). For example, here, the start of the server is carried out by using IPMI (Intelligent Platform Management Interface) and so on. The physical server 5 which completed the start processing transmits a start completion report to the integrated management apparatus 1 through the server management apparatus 4 (Steps S 635 and S 636 ). The integrated management apparatus 1 stores the data showing that the maintenance processing of the physical server 5 is completed and the server 5 is started. This data can be displayed visibly to the manager.
When starting a server, the condition of the server may be returned to the condition (HA cluster (operating system)) before the maintenance processing. FIG. 13 is a sequence diagram showing the operation of the start processing (system switched) after the maintenance processing by the server according to the present invention. Referring to FIG. 13 , the integrated management apparatus 1 controls the specified physical server 5 to start through the processing of the steps S 631 to S 634 as mentioned above. However, in case of a start instruction at the step S 632 , the integrated management apparatus 1 issues a system switching instruction. The server management apparatus 4 instructs switching of the operating system to the clustering mechanism 100 of the physical server 5 when detecting the start completion from the physical server 5 (Step S 636 ). The clustering mechanism 100 of the maintenance object server 5 upgrades the server (physical server 5 that maintenance processing is completed in this example) of the standby system to the operating system and downgrades the server of the operating system to the standby system (Step S 637 ). The clustering mechanism 100 notifies the system switching completion to the integrated management apparatus 1 through the server management apparatus 4 (Steps S 638 and S 639 ).
As above mentioned, by the integrated control of the integrated management apparatus 1 , the server of the HA cluster (operating system) is separated, and the maintenance processing (file update, the operation shutdown, and start processing) to the server is carried out. The original condition can be recovered through the system switching.
(2) Maintenance Processing to Server of HA Cluster
(Standby System)
Referring to FIG. 12 and FIG. 14 , the maintenance processing to the server set as the HA cluster (standby system) will be described. The description will be made, supposing that the physical server 5 as the maintenance object is set to the HA cluster (standby system).
FIG. 14 is a sequence diagram showing the operation of the maintenance processing (maintenance processing to the standby system server) in the first exemplary embodiment. Referring to FIG. 14 , the file update (e.g. the upgrade of the OS) to the physical server 5 of the HA cluster (standby system) will be described. Like the maintenance processing to the server of the HA cluster (operating system), through the processing of the steps S 601 to S 603 , the integrated management apparatus 1 detects that the maintenance object server 5 is the HA cluster (standby system).
When detecting that the maintenance object server 5 is the HA cluster (standby system), the integrated management apparatus 1 does not carry out the system switching and carries out the maintenance processing (file update in this example). The integrated management apparatus 1 specifies the physical server 5 as the maintenance object server and instructs the server management apparatus 4 to carry out the maintenance processing (file update in this example) (Step S 609 ). The server management apparatus 4 transmits the update file to the maintenance object server 5 and issues the file update instruction (Step S 610 ). The physical server 5 updates its own software with the received update file in response to the file update instruction (Step S 611 ). The server management apparatus 4 transmits the software update completion report of the physical server 5 to the integrated management apparatus 1 when confirming the file update completion to the physical server 5 . The integrated management apparatus 1 displays the file update completion in the maintenance object server 5 . Thus, the manager can confirm the normal end of the file update of the specified server.
The integrated management apparatus 1 stores the maintenance condition every physical server when receiving the maintenance completion report from the server management apparatus 4 or after the maintenance processing instruction (Step S 612 ). Here, the data showing that the physical server 5 is during file update, as the maintenance condition and data (for example, the version data of the software and OS) of the file update completion and the update file are stored. It should be noted that when the maintenance processing is the file update, the processing of the step S 612 may be omitted.
Next, referring to FIG. 14 , the processing which stops the operation (carries out the operation shutdown) of the physical server 5 , in order to maintain the hardware or software of the physical server 5 of the HA cluster (standby system) will be described. When detecting that the maintenance object server 5 is the HA cluster (standby system), the integrated management apparatus 1 does not carry out the system switching and carries out the maintenance processing (operation stop in this example).
In detail, the integrated management apparatus 1 specifies the physical server 5 as the maintenance object server and instructs maintenance processing (operation shutdown processing in this example) (Step S 609 ). The server management apparatus 4 issues an operation shutdown instruction to the maintenance object server 5 (Step S 610 ). The physical server 5 stops the operation (carries out the operation shutdown) in response to the operation shutdown instruction (Step S 611 ). The server management apparatus 4 transmits the operation shutdown completion report to the integrated management apparatus 1 when confirming the operation shutdown of the physical server 5 . The integrated management apparatus 1 displays that the maintenance object server 5 carries out the operation shutdown. Thus, the serviceman can confirm the operation shutdown of the specified server.
When receiving a maintenance completion report from the server management apparatus 4 or after the maintenance processing instruction, the integrated management apparatus 1 stores the condition every physical server (Step S 612 ). In this case, it is desirable that the data showing the operation condition of the maintenance object server 5 (e.g. operation shutdown), the data showing whether or not the maintenance object server 5 is during the maintenance processing, and the data of the clustering set to the maintenance object server 5 are stored. For example, it is stored that the physical server is the HA cluster (standby system) during the maintenance processing (operation shutdown). Also, the data of the clustering may contain data showing the current condition (standby system) after being switched at the step S 606 and the condition (operating system) before the switching.
The serviceman carries out the maintenance processing (e.g. the exchange and addition of the hardware, the replacement of the software, and so on) of the physical server 5 in which the operation shutdown is carried out. When the maintenance processing to the physical server 5 is completed, the manager inputs the maintenance completion instruction to the integrated management apparatus 1 . At this time, the server that the maintenance processing is completed is specified by the integrated management apparatus 1 . The integrated management apparatus 1 starts the physical server 5 , which carries out the operation shutdown for the maintenance processing, in response to the maintenance completion instruction. Because a method of start is same as the method shown in FIG. 12 , the description is omitted.
As above mentioned, after separating the server of the HA cluster (standby system) through the integrated control by the integrated management apparatus 1 , the maintenance processing (file update, the operation shutdown and the start processing) to the server can be executed.
(3) Maintenance Processing to Server Set as Part of Load Distribution Cluster
Referring FIG. 15 to FIG. 16 , the maintenance processing to a server (hereinafter, to be referred to as the load distribution system server) set as a part of the load distribution cluster will be described. A case where the physical server 5 as the maintenance object is set to the part of the load distribution cluster will be described.
FIG. 15 is a sequence diagram showing the operation of the maintenance processing (maintenance processing to the load distribution system server) of the first exemplary embodiment. Referring to FIG. 15 , the update (e.g. the upgrade of the OS) of the file to the physical server 5 set to the part of the load distribution cluster will be described. Like the maintenance processing to the server of the HA cluster (operating system), through the processing of the steps S 601 to S 603 , the integrated management apparatus 1 detects that the maintenance object server 5 is set to the part of the load distribution cluster. The clustering data which is transmitted from the server management apparatus 4 at the step S 603 contains data which specifies the load balancer 9 along with data showing that the maintenance object server 5 is the load distribution system server.
When detecting that the maintenance object server 5 is the load distribution system server, the integrated management apparatus 1 issues a change instruction of the assignment of load (processing) to the maintenance object server 5 to the specified load balancer 9 (Step S 641 ). The load balancer 9 stops the assignment of the processing to the maintenance object server 5 which is specified by the integrated management apparatus 1 in response to the load assignment change instruction (Step S 642 ). The load balancer 9 which changed the assignment of the processing assigns a load and transmits a change completion report to the integrated management apparatus 1 (Step S 643 ).
Also, the integrated management apparatus 1 waits until a flow according to the data transfer to the maintenance object server 5 becomes a non-set condition (non-set condition to all the OFS), and instructs the maintenance processing after confirming the non-set condition. In detail, when detecting that the maintenance object server 5 is the load distribution system server, the integrated management apparatus 1 specifies the MAC address of the maintenance object server 5 , and issues a confirmation request of whether or not the flow according to the data transfer to the maintenance object server 5 is set, to the OFC 3 (Step S 644 ). At this time, the MAC address of the physical server 5 is specified for the purpose to specify the maintenance object server. The OFC 3 specifies a flow as the confirmation object based on the specified MAC address, and refers to the setting data 446 of the flow table 334 to confirm whether or not a flow according to the data transfer to the physical server 5 is set to the switch (OFS) on a communication route to the physical server 5 (Step S 645 ). When the flow has been set, the OFC 3 waits for a predetermined time and confirms once again. In this case, the flow set to the OFS 4 i is set to be deleted when the predetermined time lapses (time until deletion is set to the OFS together with the flow by the OFC 3 ). Therefore, when the predetermined time passes, the flow of the confirmation object becomes the non-set condition. In the OFS 4 i , it is desirable to delete the flow in the period when there is not reception of the packet which controls processing by using the flow. Generally, the time until the flow is deleted is set as a sufficiently long time until the communication according to the flow is not carried out.
The OFC 3 repeats the confirmation processing and the wait processing at the step S 645 until the flow according to the data transfer to the physical server 5 becomes a non-set condition to all the OFSs, and transmits the confirmation result data showing the non-set condition to the integrated management apparatus 1 when confirming the non-set condition (Step S 646 ). It should be noted that an order of the load assignment change processing and the confirmation processing of a flow set may be the order and an opposite order shown in FIG. 15 and these may be carried out in parallel.
The integrated management apparatus 1 can confirm the stop of the data transfer to the maintenance object server 5 by confirming that a flow to the maintenance object server 5 is not set.
The control procedure shifts to the maintenance processing (file update in this example) when the non-set of the flow to the maintenance object server 5 is confirmed. The integrated management apparatus 1 specifies the physical server 5 as the maintenance object server and instructs the server management apparatus 4 to carry out maintenance processing (file update in this example) (Step S 647 ). The server management apparatus 4 transmits the update file to the maintenance object server 5 and issues the file update instruction (Step S 648 ). The physical server 5 updates its own software with the update file which is received in response to the file update instruction (Step S 649 ). The server management apparatus 4 transmits the software update completion report of the physical server 5 to the integrated management apparatus 1 when confirming the file update completion of the physical server 5 (Steps S 652 and S 653 ). The integrated management apparatus 1 displays the completion of the file update in the maintenance object server 5 . Thus, the manager can confirm the normal end of the file update of the specified server.
When receiving the maintenance completion report from the server management apparatus 4 or after the maintenance processing instruction, the integrated management apparatus 1 stores the maintenance condition every physical server (Step S 651 ). In this case, as the maintenance condition, data showing that the physical server 5 is during file update, and data of the file update completion and the update file (for example, the version data of the software and OS) are stored. It should be noted that when the maintenance processing is the file update, the processing of the step S 651 may be omitted.
When completing the maintenance processing (file update), the assignment of the load (processing) changed at the step S 642 is returned to the original condition. In detail, when confirming the file update of the physical server 5 , the integrated management apparatus 1 issues the change instruction of the assignment of the load (processing) to the maintenance object server 5 , to the load balancer 9 (Step S 654 ). The load balancer 9 starts the assignment of the processing to the maintenance object server 5 specified by the integrated management apparatus 1 in response to the change instruction (Step S 655 ). Which having changed the assignment of the processing, the load balancer 9 transmits a load assignment change completion report to the integrated management apparatus 1 (Step S 656 ). The integrated management apparatus 1 displays the load assignment change completion. Thus, the manager can confirm the normal end of the whole of processing according to the file update of the specified server.
Next, referring to FIG. 15 , the processing which stops the operation (carries out the operation shutdown) of the physical server 5 , in order to maintain the hardware or software of the load distribution system server (physical server 5 in this example) will be described. Because the maintenance object server 5 is the load distribution system server, the processing of the steps S 601 to S 646 shown in FIG. 15 is carried out like the above-mentioned file update processing, and the assignment of the processing to the maintenance object server 5 is stopped and it is confirmed that the flow according to the data transfer to the maintenance object server 5 is not set.
When completing the change of the load assignment and the non-set flow confirmation, the control procedure shifts to the maintenance processing (operation shutdown processing in this example). The integrated management apparatus 1 specifies the physical server 5 as the maintenance object server and instructs the maintenance processing (operation shutdown processing in this example) (Step S 647 ). The server management apparatus 4 issues the operation shutdown instruction to the maintenance object server (Step S 648 ). The physical server 5 stops the operation (carries out the operation shutdown) in response to the operation shutdown instruction (Step S 649 ). The server management apparatus 4 transmits the operation shutdown completion report to the integrated management apparatus 1 when confirming the operation shutdown of the physical server 5 (Steps S 652 and S 653 ). The integrated management apparatus 1 displays that the maintenance object server 5 carried out the operation shutdown. Thus, the manager can confirm the operation shutdown of the specified server.
When receiving the maintenance completion report from the server management apparatus 4 or after the maintenance processing instruction, the integrated management apparatus 1 stores the condition every physical server (Step S 612 ). In this case, it is desirable that the data showing the operation condition of the maintenance object server 5 (e.g. operation shutdown), the data showing whether or not the maintenance object server 5 is in the maintenance processing, and the data of the clustering set to the maintenance object server 5 are stored. For example, it is stored that the physical server 5 is the load distribution system server which in the maintenance processing (operation shutdown).
The serviceman carries out the maintenance processing (e.g. the exchange and addition of the hardware, the replacement of software, and so on) of the physical server 5 which carried out the operation shutdown. When the maintenance processing to the physical server 5 is completed, the manager inputs the maintenance completion instruction to the integrated management apparatus 1 . At this time, the server in which maintenance processing is completed is specified by the integrated management apparatus 1 . The integrated management apparatus 1 starts the physical server 5 , in which the operation shutdown is carried out for the maintenance processing, in response to the maintenance completion instruction.
FIG. 16 is a sequence diagram showing a start processing operation after the maintenance processing by the load distribution system server according to the present invention. Referring to FIG. 16 , the details of the start processing operation of the server after the maintenance processing to the load distribution system server will be described. In response to the maintenance completion instruction (server specification) from the serviceman, the integrated management apparatus 1 acquires the condition of the server which is specified by the serviceman, from a list of servers in the maintenance processing (Step S 631 ). Here, the condition showing that the physical server 5 is the load distribution system server in the operation shutdown (maintenance processing) is acquired. The integrated management apparatus 1 instructs the start of the specified server (physical server 5 that maintenance processing is completed) (Step S 632 ). The server management apparatus 4 start the specified physical server 5 (Steps S 633 and S 634 ). For example, here, the start of the server is carried out by using IPMI and so on.
The physical server 5 which has been started transmits the start completion report to the integrated management apparatus 1 through the server management apparatus 4 (Steps S 635 and S 636 ). When the start of the maintenance object server 5 is completed, the assignment of the load (processing) changed at the step S 642 is returned to the original condition. In detail, when confirming the file update of the physical server 5 , the integrated management apparatus 1 issues the change instruction of the assignment of the load (processing) to the maintenance object server 5 , to the load balancer 9 (Step S 661 ). The load balancer 9 starts the assignment of the processing to the maintenance object server 5 specified by the integrated management apparatus 1 in response to the change instruction (Step S 662 ). When changing the assignment of the processing, the load balancer 9 assigns a load and transmits the change completion report to the integrated management apparatus 1 (Step S 663 ). The integrated management apparatus 1 displays the load assignment change completion. Thus, the manager can confirm the normal end of the whole processing according to the file update of the specified server.
As above mentioned, through the integrated control by the integrated management apparatus 1 , the load assignment is controlled to separate the load distribution system server and the maintenance processing (file update, the operation shutdown and the start processing) to the load distribution system server can be carried out. At this time, by the flow monitoring function by the OFC 3 , it is possible to wait the maintenance processing until a flow of the transfer data to the maintenance object server becomes non-set.
(4) Maintenance Processing to Independent Server
Referring to FIG. 17 to FIG. 19 , the maintenance processing to the independently operated server (hereinafter, to be referred to as an independent server) will be described. The description will be made, supposing that the physical server 5 as the maintenance object is the independent server.
When maintaining the independent server, a method of processing is different depending on whether or not the VMM (virtual machine monitor) is operating on the server. The update and exchange of the hardware or software is carried out after stopping the operation. FIG. 17 is a sequence diagram showing the shutdown operation to the independent server (the VMM does not operate) of the first exemplary embodiment. Referring to FIG. 17 , like the maintenance processing to the server of the HA cluster (operating system), through the processing of the steps S 601 to S 603 , the integrated management apparatus 1 detects that the maintenance object server 5 is the independent server.
When detecting that the maintenance object server 5 is the independent server, the integrated management apparatus 1 specifies the maintenance object server to the VM management apparatus 2 and issues an operation confirmation request of the VMM (Step S 671 ). The VM management apparatus 2 transmits operation situation data showing whether or not the VMM is operating on the physical server 5 which is specified as the maintenance object server, to the integrated management apparatus 1 (Step S 672 ). The integrated management apparatus 1 displays the operation situation of the VMM in the maintenance object server 5 (Step S 673 ). The serviceman can set whether or not the maintenance object server 5 should be stopped by confirming the operation situation. Generally, when the VMM is not operating on the maintenance object server 5 , the serviceman issues an instruction to stop the maintenance object server 5 by using the integrated management apparatus 1 .
The integrated management apparatus 1 specifies the physical server 5 as the maintenance object server and instructs operation shutdown processing (Step S 674 ). The server management apparatus 4 issues the operation shutdown instruction to the maintenance object server 5 (Step S 675 ). The physical server 5 carries out the operation shutdown in response to the operation shutdown instruction (Step S 676 ). The server management apparatus 4 waits for a predetermined time, and transmits the operation shutdown completion report to the integrated management apparatus 1 when confirming that the operation shutdown of the physical server 5 (Steps S 677 and S 678 ). The integrated management apparatus 1 displays that the maintenance object server 5 stopped in the operation. Thus, the serviceman can confirm the operation shutdown of the specified server.
On the other hand, when the VMM is operating on the maintenance object server 5 , the migration processing of the virtual machine (VM) is carried out by the operation shown in FIG. 18A and FIG. 18B . For example, when the maintenance object unit is the host OS of the physical server 5 and hardware, the VM 101 to the VM 10 n are migrated to the other physical server.
FIG. 18A and FIG. 18B are a sequence diagram showing the operation of the preparation processing of the maintenance processing to the independent server (the VMM operates) in the first exemplary embodiment. Referring to FIG. 18A , like the maintenance processing to the server of the HA cluster (operating system), the integrated management apparatus 1 detects that the maintenance object server 5 is the independent server, through the processing of the steps S 601 to S 603 .
When detecting that the maintenance object server 5 is the independent server, the integrated management apparatus 1 specifies the maintenance object server to the VM management apparatus 2 and issues the operation confirmation request of the VMM (Step S 671 ). The VM management apparatus 2 transmits operation situation data showing whether or not the VMM is operating on the physical server 5 which is specified as the maintenance object server, to the integrated management apparatus 1 (Step S 672 ). The integrated management apparatus 1 displays the operation situation of the VMM at the maintenance object server 5 (Step S 673 ). The serviceman can set whether or not the maintenance object server 5 is stopped, by confirming an operation situation. Here, the VMM is operating is shown.
When detecting the operation of the VMM, the integrated management apparatus 1 specifies the VMM and requires data (VMM data 324 ) of the VM which is operating on the maintenance object server 5 for the VM management apparatus 2 (Step S 681 ). The VM management apparatus 2 transmits a list (VMM data 324 ) of the VMs which are operating on the specified VMM to the integrated management apparatus 1 (Step S 682 ). The integrated management apparatus 1 sets a migration destination of each VM shown in the acquired VMM data 324 (Step S 683 ).
It is desirable that the migration destination of the VM is the VMM which is accessible to the same storage unit as a migration object VM. This is because the processing which access limitation to the storage unit is changed is sometimes added at the time of the migration of the virtual machine. Also, when the virtual switch is not a switch controlled by a flow set by the OFC 3 (in case of the layer 2 switch to which the open flow technique is not applied), a migration destination of the VM is necessary to belong to a subnet which is identical to that before the migration. When the virtual switch functions as the OFS, the VMM which belongs to a different subnet may be set as the migration destination of the VM.
Also, when there are a plurality of VMMs which meet the above-mentioned condition, it is desirable that the VMM which meets the following conditions (a) to (c) is primarily set as the migration destination. That is, it is desirable to primarily set:
(a) a VMM that itself is directly connected to the last stage switch (OFS 4 i ) which is directly connected to a migration source VMM,
(b) a VMM that the number of the OFS 4 i is less which is used for communication with the migration source VMM in the transfer of memory images which accompanies the migration, and
(c) a VMM which is connected with the OFS on the communication route used by the migration source VMM.
By primarily setting the VMM which meets the above condition (a) as the migration destination, a switch which resetting a flow with route change becomes only the last stage switch. Also, the switch which undergoes influence of the transfer of the memory image which accompanies the migration of the VM becomes only the last stage switch.
By primarily setting the VMM which meets the above condition (b) as a migration destination, the number of the switches which undergo influence of the transfer of the memory image which accompanies the migration of the VM can be minimized. Also, the VMM can be selected in which the used resource and load minimum.
By primarily setting the VMM which meets the above condition (c) as a migration destination, the number of the switches in which a flow is reset with route change can be made little.
Moreover, it is desirable that the VMM is determined which becomes the migration destination according to a lower rule (e.g. selected based on the random number), when there are a plurality of VMMs which meet either of the above conditions (a) to (c).
When the migration destination of the VM is determined, the control procedure shifts to the migration processing of the VM. First, the integrated management apparatus 1 issues the VM migration preparation instruction to the OFC 3 (Step S 684 ). The OFC 3 executes the preparation processing of the VM migration in response to the migration preparation instruction (Step S 685 ). The VM migration preparation processing will be described later in detail. However, the OFC 3 calculates a data transfer route to the migration destination VM and the setting of the transfer route of the memory image for the VM migration and carries out the generation and setting of a flow using the route. When the VM migration preparation processing is completed, the OFC 3 notifies the migration destination set every VM to the VM management apparatus 2 , and the integrated management apparatus 1 instructs the migration of the VM (Step S 686 ). The integrated management apparatus 1 waits for completion of the migration of all the instructed VMs.
The VM management apparatus 2 executes the migration processing of the VM which operates on the maintenance object server 5 in response to the migration instruction from the integrated management apparatus 1 (Step S 687 ). The migration processing of the VM can be realized by flow setting to the OFS 4 i and the virtual switches 11 and 21 . The details of the migration processing of the VM will be described later.
Referring to FIG. 19 , when receiving a VM migration completion report from the VM management apparatus 2 , the integrated management apparatus 1 specifies the physical server 5 as the maintenance object server and instructs the server management apparatus 4 to carry out the maintenance processing (file update in this example) (Steps S 691 and S 692 ). The server management apparatus 4 transmits the update file to the maintenance object server 5 and issues the file update instruction (Step S 693 ). The physical server 5 updates its own software (e.g. host OS) with the update file which is received in response to the file update instruction (Step S 694 ). The server management apparatus 4 transmits the software update completion report of the physical server 5 to the integrated management apparatus 1 , when confirming the file update completion in the physical server 5 . The integrated management apparatus 1 displays the file update completion in the maintenance object server 5 . Thus, the manager can confirm the normal end of the file update of the specified server.
When receiving the maintenance completion report from the server management apparatus 4 or after the maintenance processing instruction, the integrated management apparatus 1 stores the maintenance condition every physical server (Step S 695 ). In this case, as the maintenance condition, the data showing that the physical server 5 is in the file update state, and the data of the file update completion and update file (for example, the version data of the software and OS) are stored. It should be noted that when the maintenance processing is the file update, the processing of the step S 695 may be omitted.
When maintaining the hardware or software of the maintenance object server which is the independent server, the operation shutdown processing of the maintenance object server is carried out as the maintenance processing shown in FIG. 19 . In detail, referring to FIG. 19 , after the VM completes the migration, the physical server 5 is specified as the maintenance object server and maintenance processing (operation shutdown processing in this example) is instructed (Step S 692 ). The server management apparatus 4 issues the operation shutdown instruction to the maintenance object server 5 (Step S 693 ). The physical server 5 carries out the operation shutdown in response to the operation shutdown instruction (Step S 694 ). The server management apparatus 4 transmits the operation shutdown completion report to the integrated management apparatus 1 , when confirming the operation shutdown of the physical server 5 . The integrated management apparatus 1 displays that the maintenance object server 5 carries out the operation shutdown. Thus, the manager can confirm the operation shutdown of the specified server.
When receiving the maintenance completion report from the server management apparatus 4 or after the maintenance processing instruction, the integrated management apparatus 1 stores the condition every physical server (Step S 695 ). In this case, it is desirable that the data showing the operation condition of the maintenance object server 5 (e.g. operation shutdown), the data showing whether or not the maintenance object server 5 is in the maintenance state, and the data of the clustering set to the maintenance object server 5 are stored. For example, it is stored that the physical server 5 is the independent server in the maintenance state (operation shutdown).
The serviceman carries out the maintenance processing (e.g. the exchange and addition of the hardware, the replacement of the software, and so on) of the physical server 5 which carried out the operation shutdown. When the maintenance processing to the physical server 5 is completed, the manager inputs the maintenance completion instruction to the integrated management apparatus 1 . At this time, the server in which maintenance processing is completed is specified by the integrated management apparatus 1 . The integrated management apparatus 1 starts the physical server 5 , which carried out the operation shutdown for the maintenance processing, in response to the maintenance completion instruction. Because a method of starting is same as the method shown in FIG. 12 , the description is omitted.
As mentioned above, through the integrated control by the integrated management apparatus 1 , the independent server on which the VMM operates is separated from the system and the maintenance processing (file update, the operation shutdown and the start processing) to the server is executed. According to the present invention, when carrying out the maintenance processing to the server on which the VMM is operating, through the set change of the flow by the OFC 3 , the VM which operates on the maintenance object server is migrated to another server (VMM). Thus, without stopping the operation of the VM, the maintenance processing of the hardware of the physical server and the host OS (e.g. update and exchange of a file, and repair) can be carried out. Also, because the VM can be migrated only by the setting of the flow to the OFS 4 i , the setting on the side of IT becomes unnecessary.
Second Exemplary Embodiment
Referring to FIG. 20 to FIG. 25B , the maintenance processing to switch (OFS 4 i ) of the present invention will be described. In the present invention, after separating the OFS 4 i as the maintenance object by the setting change of the flow by the OFC 3 from the system (communication route), the maintenance processing to the OFS 4 i is carried out.
FIG. 20 is a sequence diagram showing the operation of the maintenance processing to the switch in the second exemplary embodiment. First, referring to FIG. 20 and FIG. 21 , the file update processing to the OFS 4 i will be described. The manager operates the integrated management apparatus 1 and specifies the OFS 4 i as the maintenance object (file update object in this example) and instructs the file update. The integrated management apparatus 1 specifies the OFS 4 i as the maintenance object to the OFC 3 and instructs a route detour (Step S 701 ). Here, the OFS 42 is supposed to be specified as the maintenance object, and to be referred to as the maintenance object switch 42 .
The OFC 3 verifies whether or not the detour is possible by using the specified switch, in response to the route detour instruction from the statistic management apparatus 1 (Step S 702 ). FIG. 21 is a flow chart showing the details of the detour verification processing at the step S 702 . Referring to FIG. 21 , the OFC 3 generates the topology where the maintenance object switch 42 which is specified in case of the route detour instruction does not exist (Step S 721 ). Next, the OFC 3 verifies whether or not the communication routes to all the endpoints can calculate from the topology generated at the step S 721 . In detail, the communication route is calculated from the topology generated at the step S 721 to all the combination of the endpoints as the external network 8 and the nodes (physical servers 5 and 6 ) (Step S 722 ).
When the communication route can be calculated from the topology generated at the step S 721 to all the combinations of the endpoints, the OFC 3 verifies whether or not alternate route has an influence on the valid communication route. In detail, the OFC 3 calculates the communication route from the topology generated at the step S 721 by using each endpoint of the valid communication route (Steps S 723 No and S 725 ). At this time, the communication route between the endpoints which do not have an influence on the valid communication route can be calculated by using, for example, the Dijkstra method. Here, the valid communication route is a communication route corresponding to a flow possible to set to the OFS 4 i of the flows set to the flow table 334 and shows a usable communication route at present. When there is not a combination of the endpoints which can not be calculate the communication route at the step S 725 , the control procedure shifts to the invalidation processing (Step S 703 ) of the maintenance object switch 42 shown in FIG. 20 .
On the other hand, when the combinations of the endpoints exists in which the communication route can not be calculated at the step S 722 and the step S 725 , the OFC 3 notifies the combinations (sets) of the endpoints in which the communication route can not be calculated, to the integrated management apparatus (Steps S 723 Yes and S 726 Yes and S 724 ). In this case, the integrated management apparatus 1 displays that the endpoints exist in which the communication route can not exist, and the sets of such endpoints. When there are the combinations of the endpoints in which the communication route can not be calculated at the step S 725 , the OFC 3 notifies to the integrated management apparatus 1 , that a current session can not be sustained by setting a detour. Thus, the integrated management apparatus 1 displays that there is the session which can not be sustained for communication by setting the detour, and the endpoint of the session.
The manager confirms an influence on the current communication due to the detour setting which is displayed in the integrated management apparatus 1 and permission or non-permission of the detour setting, and determines a method for the maintenance processing to the OFS 42 . The method for the maintenance processing when the detour route can not be set will be described later.
Referring to FIG. 20 , in the detour verification processing at the step S 702 , the detour route of the maintenance object switch 42 can be calculated. When determining that there is not the influence on the current communication route due to the detour route, the OFC 3 deletes or invalidates the maintenance object switch 42 in the topology data 335 (Step S 703 ). A switch invalidated in the topology data 335 is not used for the calculation of the communication route since then.
The OFC 3 generates a flow corresponding to a new the communication route (detour route) which detours the maintenance object switch (Step S 704 ). In detail, the OFC 3 calculates the communication route (hereinafter, to be referred to as a detour route) from the topology data generated at the step S 702 by using the endpoints of a valid communication route (hereinafter, to be referred to as a route before detour). Next, the OFC 3 generates a flow set to each switch on the calculated detour route. The detour route is calculated to the combinations of the endpoints of all the routes before detour, and the flow set to each switch on each detour route is generated. These flows are all set as the flows (valid flows), which can be set to the switch. According to the flows which are generated here, the OFS 4 i is controlled to transfer a reception packet through the detour route.
The OFC 3 sets the flow generated at the step S 704 to each of the OFSs on the detour route (Steps S 705 and S 706 ). Also, the OFC 3 deletes the flow corresponding to the route before the detour from each OFS on the route before detour (Steps S 707 and S 708 ). In an example shown in FIG. 20 , the setting and deletion processing of a flow is shown to the OFS 41 which is on both of the communication routes and the route before detour.
The OFC 3 deletes (or invalidates) the flow corresponding to the route before detour set to the flow table 334 , and registers (validates) the flow group generated at the step S 704 as the usable flows (Step S 709 ). As mentioned above, through the setting of the flow corresponding to the detour route, the communication route is changed, and the communication route which goes around the maintenance object switch 42 is established. When the flow registration is completed, the OFC 3 transmits the detour completion report to the integrated management apparatus 1 (Step S 710 ).
When the detour processing of the communication route is completed, the control procedure shifts to the maintenance processing (file update in this example). The integrated management apparatus 1 specifies the OFS 42 as the maintenance object switch and instructs the OFC 3 to carry out the maintenance processing (file update in this example) (Step S 711 ). The OFC 3 transmits the update file to the maintenance object switch 42 and issues the file update instruction (Step S 712 ). The OFS 42 updates its own software with the update file which is received in response to the file update instruction (Step S 713 ). The OFC 3 transmits the software update completion report of the maintenance object switch 42 to the integrated management apparatus 1 when confirming the file update completion in the OFS 42 . The OFC 3 validates or adds the maintenance object switch which completed the file update in the topology data 335 after the file update instruction or after receiving file update completion. The integrated management apparatus 1 displays the file update completion in the maintenance object switch 42 . Thus, the manager can confirm the normal end of the file update of the specified server.
In this case, after the file update of the maintenance object switch 42 , the changed communication route may be returned to the original condition by the setting of the flow. However, it is desirable not to carry out the re-change of the communication route by considering the processing load necessary for the resetting of the flow and an influence on another communication due to the resetting.
Next, referring to FIG. 20 , the processing which stops the operation (carries out the operation shutdown) of the OFS in order to maintain the hardware or software of switch (OFS) will be described. Because the maintenance object switch 42 is bypassed or detoured, the processing at the steps S 701 to S 710 shown in FIG. 20 is carried out like the above-mentioned file update processing and the change of the communication route to the detour route is carried out.
When the setting of the detour route of the communication route is completed, the control procedure shifts to the maintenance processing (operation shutdown processing in this example). The integrated management apparatus 1 specifies the OFS 42 as the maintenance object switch and instructs the maintenance processing (operation shutdown processing in this example) (Step S 711 ). The OFC 3 issues the operation shutdown instruction to the maintenance object switch 42 (Step S 712 ). The OFS 42 carries out the operation shutdown processing in response to the operation shutdown instruction (Step S 713 ). The OFC 3 transmits the operation shutdown completion report to the integrated management apparatus 1 when confirming the operation shutdown of the OFS 42 . The integrated management apparatus 1 displays that the maintenance object switch 42 stopped in the operation. Thus, the manager can confirm the operation shutdown of the specified switch.
The serviceman carries out the maintenance processing (e.g. the exchange and addition of the hardware, the replacement of the software, and so on) of the OFS 42 which stopped the operation. When the maintenance processing to the OFS 42 is completed, the manager inputs the maintenance completion instruction to the integrated management apparatus 1 . At this time, the switch that the maintenance processing is completed is specified by the integrated management apparatus 1 . The integrated management apparatus 1 starts the switch, which stopped the operation for the maintenance processing, in response to the maintenance completion instruction.
FIG. 22 is a sequence diagram showing the start processing operation of a switch after the maintenance processing of the server according to the present invention. Referring to FIG. 22 , the details of the start processing operation of the switch after the maintenance processing will be described. In response to the maintenance completion instruction (switch specification) by the manager, the integrated management apparatus 1 instructs the OFC 3 to start the specified switch (OFS 42 in which the maintenance processing is completed) (Step S 731 ). The OFC 3 starts the specified OFS 42 (Steps S 732 and S 733 ). The OFS 42 which completed the start processing transmits a start completion report to the OFC 3 (Step S 734 ). When confirming that the OFS 42 is started, the OFC 3 carries out the validation or addition of the maintenance object switch (OFS 42 in this example) in the topology data 335 (Step S 735 ). Thus, the communication route which passes the OFS 42 can be generated in case of the communication route generation processing since then. Although not shown, the OFC 3 may transmit the start completion report of the OFS 42 to the integrated management apparatus 1 . In this case, it is desirable that the integrated management apparatus 1 stores the data showing that the OFS 42 is started after the maintenance processing. This data can be displayed visibly to the manager.
As mentioned above, through the integrated control by the integrated management apparatus 1 , a switch is separated from the system and the maintenance processing (file update and the operation shutdown and the start processing) is executed to the switch. Also, the restoration processing to the original condition due to the system switching can be controlled integratedly by the integrated management apparatus 1 .
When carrying out the operation shutdown processing as at the time of the file update of the server, the changed communication route may be returned to the original condition by the setting of the flow after the maintenance object switch 42 re-starts. However, it is desirable not to carry out the re-change of the communication route by considering the processing load necessary for the resetting of the flow and the influence on another communication due to the resetting.
Third Exemplary Embodiment (Modification of Second Exemplary Embodiment)
When the communication route is changed in the maintenance processing of the switch, it is required to reduce a packet loss. In the maintenance processing of the third exemplary embodiment, a data transfer is carried out during a predetermined period before the change of the communication route, by using both of the detour route and a route before detour. Thus, the packet loss which accompanies the flow change can be made little. Hereinafter, referring to FIG. 23A and FIG. 23B , the details of the maintenance processing operation in the third exemplary embodiment will be described. The description will be made supposing that the maintenance object switch is the OFS 42 , a switch different from the endpoint on the detour route is the OFS 41 , and the switch of the endpoint is the OFS 43 .
FIGS. 23A and 23B are a sequence diagram showing the maintenance processing operation to the switch in the third exemplary embodiment. Referring to FIG. 23A , by the method of maintenance processing in the third exemplary embodiment, the detour verification and the invalidation of the maintenance object switch 42 in the topology data 335 are carried out though the processing at the steps S 701 to S 703 , like the second exemplary embodiment.
The OFC 3 generates the flow corresponding to a new communication route (detour route) which goes around the maintenance object switch (Step S 741 ). At this time, the OFC 3 generates a flow to transfer data only to the detour route, like the second exemplary embodiment, and also generates a flow to transmit packet data to both of the detour route and the route before detour by copying the packet data.
The OFC 3 sets the flow for transferring data only through the detour route, of the flows generated at the step S 741 , to a corresponding OFS (OFS 41 ) other than the endpoints on the detour route (Steps S 742 and S 743 ). Next, the OFC 3 sets the flow for copying the packet data and for transmitting it to both of the detour route and the route before detour, to the switch (OFS 43 ) of the endpoint on the detour route (Steps S 744 and S 745 ). After waiting for a predetermined tie, the OFC 3 which set the flow to the OFS on the detour route instructs the switch (OFS 43 ) of the endpoint on the detour route to change the flow set at the step S 745 into the flow for transferring data only to the detour route generated at the step S 741 (Steps S 746 and S 747 ). Subsequently, the OFC 3 deletes the flow corresponding to the route before detour from each OFS on the route before detour (Steps S 748 and S 749 ).
Since then, like the second exemplary embodiment, the registration (validation) processing of the flow into the OFC 3 and the maintenance processing (update of the file or the operation shutdown processing) are carried out through the processing of the steps S 709 to S 713 .
According to the maintenance method in the present exemplary embodiment, because the data transfer is carried out through two routes of the detour route and the route before detour by the switch (OFS 4 i ) of the endpoint for a predetermined time, the packet loss in change of the communication route can be decreased.
In the second or third exemplary embodiment, when there is a set of the endpoints to which the detour route can not be calculated, the calculation of the detour route can be made possible by changing a condition (system configuration) of the endpoint (server) by the control by the integrated management apparatus 1 . A method of changing an endpoint (server) is different according to the endpoint being either of the HA cluster (operating system) server, the HA cluster (standby system) server, the load distribution system server, and the single server on which the VMM operates.
FIG. 24A and FIG. 24B are a flow chart showing the endpoint change processing operation for the detour route generation in case of the maintenance processing to the switch. Referring to FIG. 24A , in case of the maintenance processing to the switch, the details of the endpoint change processing when the detour route can not be calculated will be described. When the endpoint exists to which the detour route can not be calculated in case of detour route verification processing at the above-mentioned step S 702 (Step S 726 ), the OFC 3 notifies the setting of the endpoint to which the communication route can not be calculated, to the integrated management apparatus 1 . The integrated management apparatus 1 confirms a situation (cluster configuration) of the endpoint (server) other than the external network 8 being notified from the OFC 3 (Step S 801 ). In detail, like the above-mentioned steps S 601 to 603 , the integrated management apparatus 1 specifies the endpoint (server) which is notified from the OFC 3 and acquires each clustering data from the server management apparatus 4 . The acquired clustering data is stored in the storage unit.
When there is a single server in the endpoint (server) which is notified from the OFC 3 , the integrated management apparatus 1 confirms whether or not the VMM is operating on the single server, to the VM management apparatus 2 , like the above-mentioned steps S 671 to S 672 (Steps S 802 and S 803 ). At this time, when the single server on which the VMM is not operating is contained in the notified endpoint (server), the integrated management apparatus 1 displays a session in which communication can not be sustained and a set which contains the endpoint (single server) of the session, and ends the detour route generation processing (Steps S 803 Yes and S 804 ).
On the other hand, when the single server is not contained in the endpoint which is notified from the OFC 3 (Step S 802 No), or, when the single server on which the VMM is not operating is not contained (Step S 803 No), the integrated management apparatus 1 carries out the endpoint change processing by a method according to the condition (clustering configuration) set to the endpoint (server).
First, the integrated management apparatus 1 extracts an endpoint (server) as a change object from the endpoint which is notified from the OFC 3 (Steps S 805 and S 806 ). When the extracted change object endpoint is the HA cluster (operating system) server, the integrated management apparatus 1 issues an instruction to the server management apparatus 4 so as to upgrade the server of the HA cluster (standby system) to the HA cluster (operating system) (Steps S 807 Yes and S 808 ). Next, the integrated management apparatus 1 issues a downgrade instruction to the server management apparatus 4 so as to downgrade the server of the HA cluster (operating system) to the HA cluster (standby system) (Step S 809 ). Then, the integrated management apparatus 1 issues an instruction to the server management apparatus 4 so as to stop the downgraded server of the HA cluster (standby system) (Step S 810 ). The server management apparatus 4 carries out the switching processing between the operating system and the standby system and the operation shutdown processing of the HA cluster (standby system) in response to each instruction from the integrated management apparatus 1 . When the switching processing between the operating system and the standby system and the operation shutdown of the endpoint (server) are completed, the control procedure shifts to the step S 805 .
When the change object endpoint extracted at the step S 806 is the HA cluster (standby system) server, the integrated management apparatus 1 issues an instruction to the server management apparatus 4 so as to stop the endpoint (HA cluster (standby system) server) (Steps S 811 Yes and S 810 ). The server management apparatus 4 carries out the operation shutdown processing of the HA cluster (standby system) in response to the instruction from the integrated management apparatus 1 . When the operation shutdown of the endpoint (server) is completed, the control procedure shifts to the step S 805 .
When the change object endpoint extracted at the step S 806 is the load distribution system server, the integrated management apparatus 1 issues an instruction to the load balancer 9 so as to stop a load assignment to the endpoint (server) (Steps S 812 Yes and S 813 ). The load balancer 9 stops the load assignment to the change object endpoint (server) in response to the instruction from the integrated management apparatus 1 , like the above-mentioned step S 642 . Next, the integrated management apparatus 1 issues a flow stop confirmation request to the change object endpoint to the OFC 3 (Step S 814 ). The OFC 3 confirms that the flow for controlling the data transfer to the change object endpoint is deleted from each switch, like the above-mentioned step S 645 , and reports it to the integrated management apparatus 1 . When confirming the stop of the data transfer to the change object endpoint, the integrated management apparatus 1 issues an instruction to the server management equipment so as to stop the endpoint (Step S 815 ). The server management apparatus 4 carries out the operation shutdown processing of the endpoint (server) in response to the instruction from the integrated management apparatus 1 . When the operation shutdown of the endpoint (server) is completed, the control procedure shifts to the step S 805 .
When the change object endpoint extracted at the step S 806 is a single server, the integrated management apparatus 1 requests the data (VMM data 324 ) of the VM which is operating in the endpoint (VMM), to the VM management apparatus 2 (Steps S 816 Yes and S 817 ). The VM management apparatus 2 returns the list (VMM data 324 ) of the VMs of the specified endpoints (VMM), to the integrated management apparatus 1 , like the above-mentioned step S 681 . Next, the integrated management apparatus 1 determines the migration destination of each VM shown in the VM list (VMM data 324 ) which is acquired like the above-mentioned step S 683 and issues the migration instruction of the VM to the VM management apparatus 2 (Step S 818 ). The VM management apparatus 2 migrates the VM by using the OFC 3 , like the step S 687 . When confirming the VM migration, the integrated management apparatus 1 issues an instruction to the server management apparatus 4 so as to stop the endpoint (Step S 819 ). The server management apparatus 4 carries out the operation shutdown processing of the endpoint (server) in response to the instruction from the integrated management apparatus 1 . When the operation shutdown of the endpoint (server) is completed, the control procedure shifts to the step S 805 .
The processing of the above-mentioned steps S 805 to S 819 is repeated until it is carried out to all the endpoints notified from the OFC 3 . When all the endpoints are changed, the control procedure shifts to the above-mentioned step S 703 , the invalidation of the maintenance object, the calculation of the detour route, the setting of the flow and the maintenance processing (the file update, exchange of hardware and so on) are carried out, as shown in the first and second exemplary embodiments. At this time, the maintenance object switch to be detoured may stop in the operation. Also, the condition (clustering configuration, the operation situation and so on) of the changed endpoint may be stored in the storage unit.
Next, the operation after the maintenance processing will be described. When knowing the maintenance processing completion by the report from the OFC 3 or an input by the manager, the integrated management apparatus 1 restores a condition of the changed endpoint according to the condition of each endpoint (server) which is stored in the above-mentioned endpoint change processing (Step S 801 ). FIG. 25A and FIG. 25B are a flow chart showing the endpoint recovery processing operation after the maintenance processing to the switch. In case of confirming a condition of the stored endpoint and existence of an un-restored endpoint (server), the integrated management apparatus 1 extracts a restoration object endpoint and carries out the restoration processing of the server condition (Steps S 831 and S 832 Yes and S 833 ).
At first, when the extracted restoration object endpoint (server) is the HA cluster (operating system) server, the integrated management apparatus 1 instructs the start of the server of the HA cluster (standby system) to the server management apparatus 4 (Steps S 834 Yes and S 835 ). Next, the integrated management apparatus 1 issues an instruction to the server management apparatus 4 so as to upgrade the server of the HA cluster (standby system) to the HA cluster (operating system) (Step S 836 ). Then, the integrated management apparatus 1 issues an instruction to the server management apparatus 4 so as to downgrade the server of the HA cluster (operating system) to the HA cluster (standby system) (Step S 809 ). The server management apparatus 4 carries out the start processing of the HA cluster (standby system) and the switching processing between the operating system and the standby system in response to each instruction from the integrated management apparatus 1 . When the start of the endpoint (server) and the restoration to the operating system are completed, the control procedure shifts to the step S 832 .
When the restoration object endpoint extracted at the step S 833 is the HA cluster (standby system) server, the integrated management apparatus 1 issues the instruction to the server management apparatus 4 so as to start the endpoint (HA cluster (standby system) server) (Steps S 838 Yes and S 839 ). The server management apparatus 4 carries out the start processing of the HA cluster (standby system) in response to the instruction from the integrated management apparatus 1 . When the start of the endpoint (server) is completed, the control procedure shifts to the step S 832 .
When the restoration object endpoint extracted at the step S 833 is the load distribution system server, the integrated management apparatus 1 issues the start instruction of the restoration object endpoint to the server management apparatus 4 (Steps S 840 Yes and S 841 ). The server management apparatus 4 carries out the start processing to the endpoint (server) in response to the instruction from the integrated management apparatus 1 . Next, the integrated management apparatus 1 issues an instruction to the load balancer 9 so as to stop the load assignment to the endpoint (server) (Step S 842 ). The load balancer 9 resumes the load assignment to the change object endpoint (server) in response to the instruction from the integrated management apparatus 1 , like the above-mentioned step S 662 . When the start of the endpoint (server) and the load assignment are resumed, the control procedure shifts to the step S 832 .
When the restoration object endpoint extracted at the step S 833 is a single server, the integrated management apparatus 1 issues the start instruction of the restoration object endpoint to the server management apparatus 4 (Steps S 843 Yes and S 844 ). The server management apparatus 4 carries out the start processing of the endpoint (server) in response to the instruction from the integrated management apparatus 1 . Next, the integrated management apparatus 1 issues the migration instruction (restoration instruction) of the VM to the VM management apparatus 2 (Step S 845 ). When the start processing of the endpoint (server) and the migration processing of the VM are completed, the control procedure shifts to the step S 832 .
The processing of the above-mentioned steps S 832 to S 845 is repeated until it is carried out to all the stored restoration object endpoints. When all the endpoints are restored, the integrated management apparatus 1 displays the effect that the maintenance processing is completed.
As mentioned above, through the integrated control by the integrated management apparatus 1 , the switch which does not have any detour route is separated from the system, and the maintenance processing (file update, operation shutdown processing and the start processing) is executed to the switch.
Fourth Exemplary Embodiment (Modification of First Exemplary Embodiment)
In the fourth exemplary embodiment, when switched between the operating system and the standby system in case of the maintenance processing to the server of the HA cluster (operating system), the communication route is changed based on the open flow technique. Thus, the shortening of the setup time in case of the communication route when switched between the operating system and the standby system and the decrease of the packet loss an be made possible. Hereinafter, referring to FIG. 26A to FIG. 27B , the details of the maintenance processing to the HA cluster (operating system) server in the fourth exemplary embodiment will be described.
FIG. 26A and FIG. 26B are a sequence diagram showing the maintenance processing (maintenance processing to the operating system server) operation in the fourth exemplary embodiment. In the present exemplary embodiment, the setting of the flow corresponding to the communication route used after the system switching is carried out before the switching (Step S 604 to S 608 ) between the operating system and the standby system in the first exemplary embodiment.
Hereinafter, the details of the setting processing of the flow will be described. Like the first exemplary embodiment, the integrated management apparatus 1 detects that the maintenance object server 5 is a cluster (operating system), through the processing of the steps S 601 to S 603 , specifies the maintenance object server 5 to the OFC 3 , and instructs the setting of the flow (Step S 901 ). The OFC 3 generates the flow corresponding to the communication route which has the HA cluster (standby system) as the endpoint in response to the flow setting instruction (Step S 902 ). In detail, the communication route having as the endpoints, another endpoint of the communication route having the maintenance object server 5 which is the HA cluster (operating system) as an endpoint and the server of the HA cluster (standby system) is calculated newly by using the topology data 335 . The OFC 3 generates the flow set to the OFS 4 i on the communication route. The OFC 3 sets the flow generated at the step S 902 to each OFS 4 i on the new communication route (Steps S 903 and S 904 ).
The OFS 4 i to which the new flow is set carries out the transfer processing of packet data to both of the HA cluster (operating system) server and the HA cluster (standby system) server. Thus, the packet loss occurrence during the system switching processing to be described later can be prevented.
The OFC 3 issues a flow setting completion report to the integrated management apparatus 1 when setting the flow (Step S 905 ). The integrated management apparatus 1 instructs the server management apparatus 4 to switch the system of the maintenance object server of the operating system and the server of the standby system according to this (Step S 604 ). Like the first exemplary embodiment, the server management apparatus 4 controls the clustering mechanism 100 to downgrade the maintenance object server 5 of the operating system into the standby system, and upgrades the server of the specified standby system to the operating system (Steps S 605 and S 607 ).
When receiving the system switching completion report, the integrated management apparatus 1 issues the deletion instruction of the flow to the OFC 3 (Steps S 608 and S 906 ). The OFC 3 instructs the OFS 4 i to delete the flow corresponding to the communication route having the maintenance object server 5 as the endpoint from the OFS 4 i on the communication route (Step S 907 ). When receiving the deletion instruction, the OFS 4 i deletes the flow (Step S 908 ). Thus, the packet data for the maintenance object server 5 is transferred to the server only by using the communication route having the server which is switched to the operating system at the step S 606 as the endpoint.
When the deletion of the flow corresponding to the communication route to the maintenance object server 5 is completed, a flow deletion completion report is notified to the integrated management apparatus 1 from the server management apparatus 4 . Thus, the integrated management apparatus 1 instructs the server management apparatus 4 to carry out the maintenance processing and shifts to the maintenance processing, like the first exemplary embodiment (Step S 609 to S 612 ).
As mentioned above, because the setting of the flow used after system switching is carried out before system switching, the change time of the communication route after the system switching is reduced.
FIG. 27A and FIG. 27B are a sequence diagram showing the start processing operation after the maintenance processing of the server in the fourth exemplary embodiment. In the fourth exemplary embodiment, when starting the physical server 5 which stopped operation for the maintenance processing, the system switching and the switching of the communication route are carried out. In the present exemplary embodiment, the setting of the flow corresponding to the communication route used after the system switching is carried out before the system switching (Steps S 636 to S 639 ) between the operating system and the standby system in the first exemplary embodiment.
In detail, like the first exemplary embodiment, the physical server 5 after the maintenance processing is started by the integrated management apparatus 1 (Step S 631 to S 635 ). When confirming the start completion of the physical server 5 based on the report from the server management apparatus 4 , the integrated management apparatus 1 specifies the server to operate as the operating system and instructs the setting of the flow (Steps S 911 and S 912 ). Thus, the physical server 5 of the HA cluster (standby system) in which maintenance processing is completed is specified. The OFC 3 generates the flow corresponding to the communication route having the physical server 5 of the HA cluster (standby system) as the endpoint in response to the flow setting instruction (Step S 913 ). In detail, the communication route having another endpoint of the communication route having the HA cluster (operating system) server as the endpoint and the endpoint as the physical server 5 of the HA cluster (standby system) is calculated by using the topology data 335 . The OFC 3 generates the flow to be set to the OFS 4 i on the communication route. The OFC 3 sets the flow which is generated at the step S 913 to each OFS 4 i on the new communication route (Steps S 914 and S 915 ). It should be noted that in the deletion processing of the flow shown in FIG. 26A and FIG. 26B , when the flow to the maintenance object server 5 is not deleted and is retained in the flow table 334 of the OFC 3 , the flow generation processing at the step S 913 is omitted.
The OFS 4 i to which a new flow is set carries out the transfer processing of packet data to both of the HA cluster (operating system) server and the HA cluster (standby system) server. Thus, packet loss occurrence during the system switching processing to be described later can be prevented.
The OFC 3 issues the flow setting completion report to the integrated management apparatus 1 when setting a flow (Step S 916 ). The integrated management apparatus 1 instructs the server management apparatus 4 to carry out the system switching of the maintenance object server of the operating system and the server of the standby system (Step S 917 ). Like the first exemplary embodiment, the server management apparatus 4 controls the clustering mechanism 100 to downgrade the physical server of the operating system into the standby system, and upgrade the physical server 5 of the standby system in which the maintenance processing is completed to the operating system (Step S 636 to S 639 ).
When receiving the system switching completion report, the integrated management apparatus 1 issues the deletion instruction of the flow to the OFC 3 (Steps S 939 and S 918 ). The OFC 3 instructs the OFS 4 i to delete the flow corresponding to the communication route having the server switched from the operating system to the standby system as the endpoint from the OFS 4 i on the communication route, (Step S 919 ). When receiving the deletion instructions, the OFS 4 i deletes the flow (Step S 920 ). Thus, the packet data for the maintenance object server 5 is transferred to the server by using only the communication route having the physical server 5 switched to the operating system at the step S 606 as the endpoint.
As mentioned above, because the setting of the flow used after the system switching is carried out before the system switching in case of the start processing of the physical server after the maintenance processing, the change time of the communication route after the system switching is reduced. It should be noted that the system switching after the maintenance processing and the changing of the communication route can be omitted.
(Virtual Machine Migration Operation)
Next, the virtual machine migration operation at the steps S 684 to S 687 shown in FIG. 18B will be described.
(1) First Implementation Example
Referring to FIG. 28 to FIG. 30 , the first implementation example of the virtual machine migration operation will be described. FIG. 28 is a sequence diagram showing the first implementation example of the migration preparation processing in case of the migration processing of the virtual machine. First, referring to FIG. 28 , the first implementation example of the migration preparation processing at the step S 685 shown in FIG. 18B will be described.
When the migration destination of the VM is determined at the step S 683 , the integrated management apparatus 1 issues the VM migration preparation instruction to the OFC 3 (Step S 684 ). At this time, the integrated management apparatus 1 specifies the migration source VMM, the migration object VM, the migration destination VMM, and the migration destination VSW to the OFC 3 based on the VMM management data 323 .
When receiving the migration preparation instructions, the OFC 3 first sets the communication route and a flow for the transfer of the memory image. The OFC 3 calculates the communication route (memory image transfer route) for transferring the memory image of the migration object VM between the migration source VMM and the migration destination VMM based on the topology data 335 (Step S 104 ). Here, the area in which the memory image of the migration object VM before the migration is stored and the area in which the memory image of the migration object VM after the migration is stored are set as both endpoints, and are calculated as the memory image transfer route. The data of the calculated memory image transfer route is stored as the communication route data 336 .
The OFC 3 generates the flow (memory image transfer flow) to be set to each OFS 4 i on the memory image transfer route calculated at the step S 104 (Step S 105 ). The flow (rule 444 +action data 445 ) for the memory image transfer processing generated every OFS 4 i is related to each OFS 4 i and is registered on the flow table 334 . At this time, the setting data 446 of the memory image transfer flow is set as a “non-set” or “invalid” state.
The OFC 3 sets the memory image transfer flow to each OFS 4 i and node (Step S 106 to S 108 ). In detail, the OFC 3 instructs the OFS 4 i on the communication route to set the memory image transfer flow (Step S 106 ). The OFS 4 i instructed to set the flow sets the set flow (rule 444 +action data 445 ) to its own flow table 343 (Step S 107 ). When completing the setting of the flow, the OFS 4 i transmits the flow setting completion report to the OFC 3 (Step S 108 ). Here, the memory image transfer flow is set to the nodes on the memory image transfer route other than the OFS 4 i . Also, when the virtual switch has the configuration corresponding to the open flow technique, the memory image transfer flow is set to the virtual switch on the memory image transfer route. The setting data 446 of the memory image transfer flow set to the OFS 4 i and the virtual switch is set to an “already set” or “valid” state.
Next, the OFC 3 sets the communication route and the flow for access to the migration object VM (hereinafter, to be referred to as migration destination VM) after the VM migration. First, the OFC 3 calculates the communication route (communication route for the migration destination VM) to the migration destination VM (Step S 109 ). In detail, the OFC 3 selects the communication route data 336 in the communication route of the migration object VM from the valid communication route data 336 retained in advance. Here, the valid communication route (valid communication route data 336 ) shows the communication route where the flow exists which can be set to the OFS 4 i . The OFC 3 uses the topology data 335 to correct the communication route by changing one endpoint of the selected communication route from the migration object VM to a virtual switch connected with the migration destination VM, and calculates as the communication route for the migration destination VM. The data of the calculated communication route for the migration destination VM is stored as the communication route data 336 .
The OFC 3 generates the flow (communication flow for the migration destination VM) to be set to each OFS 4 i on the communication route for the migration destination VM which is calculated at the step S 109 (Step S 110 ). The communication flow (rule 444 +action data 445 ) for the migration destination VM generated every OFS 4 i is related to each OFS 4 i and is registered on the flow table 334 . At this time, the setting data 446 of the communication flow for the migration destination VM is set to a “non-set” or “invalid” state.
The OFC 3 reports that the migration preparation is completed, to the integrated management apparatus 1 , when generating the communication flow for the migration destination VM (Step S 111 ).
As mentioned above, in the migration preparation processing in the first implementation example, the calculation of the transfer route of the memory image of the migration object VM and the migration and the setting of the flow to control the migration, and the calculation of the communication route for access to the migration destination VM and the generation of the flow to control the communication are carried out. In the first implementation example, at the step that the setting of the memory image transfer flow to the OFS 4 i and the generation of the communication flow for the migration destination VM are completed, the migration preparation ends.
The migration processing at the step S 687 shown in FIG. 18B contains the memory image transfer processing shown in FIG. 29 and the access destination switching processing shown in FIG. 30 .
FIG. 29 is a sequence diagram showing the memory image transfer processing in the first implementation example in case of migration processing of the virtual machine. Referring to FIG. 29 , when receiving the migration ready report, the integrated management apparatus 1 issues the migration instruction to the VM management apparatus 2 (Step S 686 ). The VM management apparatus 2 issues the migration instruction to the migration source VMM (VMM 10 here as an example) and the migration destination VMM (VMM 20 here as an example) which are specified in case of the migration preparation processing (Steps S 202 and S 203 ). At this time, the VM management apparatus 2 notifies the migration object VM to the VMMs 10 and 20 . It should be noted that in case of the migration instruction at the step S 201 , the migration source VMM and the migration destination VMM may be specified.
The memory image transfer processing of the virtual machine is carried out between the VMMs 10 and 20 in response to the migration instruction from the VM management apparatus 2 (Steps S 204 to S 212 ). In detail, the VM which is specified by the VM management apparatus 2 in the migration destination VMM (hereinafter, to be referred to as a migration destination VMM 20 ) is generated (Step S 204 ). The migration source VMM (hereinafter, to be referred to as a migration source VMM 10 ) transfers the memory image of the migration object VM in response to the VM generation completion report notified from the migration destination VMM 20 (Step S 205 to S 207 ). The memory image is transferred for the VM which is generated at the step S 204 . The memory image is transferred through the memory image transfer route set at the steps S 104 to S 107 . At this time, the OFS 4 i on the memory image transfer route transfers the memory image according to the flow transferring for the memory image set at the step S 107 .
When the access to another virtual machine other than the migration object VM (e.g. data transfer) occurs during the transfer of the memory image, the OFS 4 i according to access executes the action (for example, the relay processing of data) corresponding to the header data of the reception packet according to the flow set to its own flow table 343 . In this case, by setting the memory image transfer route to the route which does not hinder access to another virtual machine that does not have relation with the migration, the migration object VM can be migrated without hindering communication with the other virtual machine.
On the other hand, when the access for the migration object VM occurs during the transfer of the memory image (for example, when data for the migration object VM is transferred), the OFS 4 i on the communication route to the migration object VM executes the action (for example, the relay processing of data) corresponding to the header data of the reception packet according to the flow set to its own flow table 343 . Here, because the flow is set, supposing that the migration object VM is operating on the VMM 10 , the data for the migration object VM is transferred to the migration object VM on the physical server 5 . The migration source VMM 10 stores the data of transferred migration object VM in the memory page of the migration object VM.
During the transfer of the memory image, there are cases that the process processing of the migration object VM and the memory page based on the data transferred for the migration object VM are changed. The changed memory page is stored in the changed page record area of the storage unit as a copy object (Step S 208 ). It is desirable that the record processing of the changed page is carried out until the migration destination VM starts the operation.
When the transfer of all the memory images related to the migration object VM is ended, the migration source VMM 10 transfers the changed page to the migration destination VMM 20 through the memory image transfer route set at the steps S 104 to S 107 (Step S 209 ). However, it is desirable that the number of the changed pages which have been stored when the transfer of all the memory images related to the migration object VM is ended is equal to or less than a predetermined number, the transfer processing of the changed page at the step S 209 is omitted. Also, during the transfer processing of the changed page at the step S 209 , the memory page is sometimes changed. Therefore, at the step S 209 , the migration source VMM 10 stores a further changed page in the changed page record area to another area, and transfers the further changed page to the migration destination VMM 20 after clearing the changed page record area.
When the transfer of all the memory images (containing the transfer of the changed page) related to the migration object VM is completed, the operation of the migration object VM (hereinafter, to be referred to as the migration source VM) which operates on the migration source VMM 10 stops (Step S 210 ). At this time, the network interface of the virtual migration source VM also stops. It should be noted that it is desirable that the migration source VMM 10 repeats the transfer of the changed pages and the record of the changed pages at the step S 209 and stop the migration source VM when the number of changed pages becomes equal to or less than a predetermined number. After the migration source VM stops, the migration source VMM 10 transfers the changed pages to the migration destination VMM 20 through the memory image transfer route set at the steps S 104 to S 107 (Step S 211 ). Thus, the transfer of the memory image from the migration source VMM 10 to the migration destination VMM is completed. Here, the VM (hereinafter, to be referred to as the migration destination VM) which is generated on the migration destination VMM 20 may start to operate, but it is desirable that the matching determination of the memory images between the migration source VM and the migration destination VM is carried out. In detail, the migration source VMM 10 confirms that the migration source VM stopped, and issues the transfer confirmation instruction to the migration destination VMM 20 (Step S 212 ). The migration destination VMM 20 transfers the memory image of the migration destination VM to the migration source VMM 10 through the memory image transfer route set at the steps S 104 to S 107 in response to the transfer confirmation instruction (Step S 213 ). The migration source VMM 10 determines whether the memory image which is transferred from the migration destination VMM 20 and the memory image of the migration source VM are coincident with each other (Step S 214 ).
At the step S 214 , when the matching of the memory images of the migration destination VM and the migration source VM is confirmed, a matching confirmation completion report is transmitted to the migration destination VMM 20 from the migration source VMM 10 (Step S 215 ). When receiving the matching confirmation completion report. The migration destination VMM 20 operates the migration destination VM (Step S 216 ). At this time, the virtual network interface in the migration destination VM becomes an operating condition.
On the other hand, when the memory image of the migration destination VM and the migration source VM does not agree of the step S 216 , the transfer processing of the memory page which does not agree is carried out (It is not in the illustration).
As mentioned above, the transfer of the memory image of the VM is carried out by using the route (memory image transfer route) which is specified by the integrated management apparatus 1 . At this time, access to the migration source VM is carried out according to the flow set to the OFS group 4 before the migration processing. Therefore, the memory image of the VM can be transferred without stopping the communication to the migration source VM. Also, because the memory image transfer route can be optionally set by the integrated management apparatus 1 , a route which does not obstruct communication to the other virtual machines can be selected. Thus, the transfer of the memory image becomes possible without influence on communication to the other virtual machines.
Generally, when the physical servers belong to an identical subnet, the data transfer between the physical servers is carried out through the switch of layer 2. However, when the physical servers belong to different subnets, the layer 3 switch must be provided between the physical servers. On the other hand, in the present invention, the transfer of the memory image is carried out by using the open flow technique in which the action (e.g. the relay operation) is determined according to a combination of the addresses of layer 1 to layer 4 and identifiers. Therefore, even when the physical servers 5 and 6 belong to the different subnets, the data transfer between the physical servers becomes possible only by changing the setting of the flow.
FIG. 30 is a sequence diagram showing the access destination switching processing operation in the migration processing of the virtual machine in the first implementation example. Here, supposing that the migration destination VM started at the step S 218 is the VM 20 m , the access destination switching processing from the migration source VM to the migration destination VM 20 m will be described. Referring to FIG. 30 , the VM 20 m generated on the migration destination VMM 20 first transmits RARP (Reverse Address Resolution Protocol) when become an operating condition (Step S 301 ). RARP is detected by the virtual switch 21 and is transferred to the OFS 4 i . When detecting the RARP, the OFS 4 i notifies the detected RARP to the OFC 3 (Step S 302 ). In detail, the OFS 4 i receives the packet data in the RARP transmission from the migration destination VM in the operating condition, and notifies the reception of the first packet to the OFC 3 , because the flow (rule) adapted for the packet data is not set. At this time, the OFS 4 i notifies the packet data or a MAC address contained in the packet data to the OFC 3 . The OFC 3 selects the communication route corresponding to the notified MAC address as the communication route for the migration destination VM and generates a communication flow for the migration destination VM. Here, the packet data in the RARP communication is transferred from the OFS 4 i and the OFC 3 acquires the MAC address of the VM 20 m in the RARP transmission.
The OFC 3 selects the communication route (communication route data 336 ) corresponding to RARP (MAC address) which is notified at the step S 302 of the valid communication route data 336 (S 303 ). Here, the communication route which passes RARP (MAC address) is selected from the communication route for the migration destination VM which is calculated at the step S 109 . Next, the OFC 3 sets the communication flow for the migration destination VM which is generated at the step S 110 to the OFS 4 i and nodes on the selected communication route (Step S 304 to S 307 ). In detail, the OFC 3 extracts the OFS 4 i and nodes on the selected communication route for the migration destination VM from the communication route data 336 and the topology data 335 and selects the communication flow for the migration destination VM corresponding to each of the extracted OFS 4 i and nodes (Step S 304 ). The OFC 3 issues the setting instruction of the communication flow for the migration destination VM which is selected every OFS 4 i (Step S 305 ). The OFS 4 i sets the transmitted communication flow for the migration destination VM in response to the setting instruction of the communication flow for the migration destination VM to its own flow table 343 (Step S 306 ). When the setting of the flow is completed, the OFS 4 i notifies a flow setting completion report to the OFC 3 (Step S 307 ). The setting data 446 of the communication flow for the migration destination VM set to the OFS 4 i is set to an “already set” and “valid” state.
The OFC 3 sets the communication flow for the migration destination VM to the OFS 4 i and nodes on the communication route for the migration destination VM, and generates the flow to connect between the migration destination VM and the virtual switch 21 by using the topology data 335 , when confirming the setting completion (Step S 308 ). The OFC 3 sets the generated flow to the virtual switch 21 (Steps S 309 and S 310 ). In detail, the OFC 3 issues the setting instruction of the flow generated at the step S 308 to the virtual switch 21 (Step S 309 ). The virtual switch 21 sets the flow transmitted from the OFC 3 to its own flow table 343 in response to the setting instruction of the flow (Step S 310 ). When the setting of the flow is completed, the virtual switch 21 notifies the flow setting completion report to the OFC 3 (Step S 311 ). The setting data 446 of the communication flow for the migration destination VM set to the virtual switch 21 is set to an “already set” or “valid” state.
When confirming the setting completion of the flow which connects the migration destination VM 20 m and the virtual switch 21 , the OFC 3 selects the flow for the migration source VM and issues the deletion instruction of the flow (Steps S 312 and S 313 ). The OFS 4 i and nodes set the flow for the migration source VM to a deletion or use impossible state (Step S 314 ). The OFS 4 i and nodes in which the deletion of the flow is ended notify a flow deletion completion report to the OFC 3 (Step S 315 ). When confirming the deletion of the flow for the migration source VM in the OFS 4 i and nodes on the communication route for the migration source VM, the OFC 3 sets the communication flow for the migration destination VM as the current use flow and sets the communication flow for the migration source VM as a non-use flow (Step S 316 ). Here, the data showing the use or non-use (valid or invalid) is set in the setting data 446 corresponding to each flow (rule 444 +action data 445 ). At this time, the unused communication flow for the migration source VM may be deleted from the flow table 334 . However, by setting the use or non-use (validation or invalidation) of the flow by the change of the setting data 446 without deleting the unused flow, the setting of the flow becomes possible without generating a flow once again when returning the migrated virtual machine to the original physical server or VMM.
Since then, the communication for the migration destination VM 20 m is executed to the VMM 20 which operates on the physical server 6 (VMM 20 ) according to the communication flow for the migration destination VM set to each OFS 4 i.
As mentioned above, according to the migration method of the present invention, the migration of the virtual machine becomes possible without stopping the communication with the virtual machine. In the present exemplary embodiment, the migration between the different physical servers has been described as an example, but the migration in the identical physical server can be realized by the similar method.
Also, according to the present invention, the setting for the transfer of the memory image and the setting for the communication with the migration destination VM can be carried out integratedly by the integrated management apparatus 1 . That is, the migration of the virtual machine can be controlled by one management apparatus. Therefore, according to the present invention, the computer system which is separately managed conventionally by the network manager and the IT manager can be managed by one management apparatus.
It should be noted that when the virtual switch 21 is a virtual switch which carries out a usual switching operation (layer 2), the processing of the steps S 308 to S 311 is omitted.
(2) Second Implementation Example
Next, referring to FIG. 29 , FIG. 31 and FIG. 32 , the migration method of the virtual machine in the computer system according to the second implementation example of the present invention will be described.
In the migration method of the virtual machine of the second implementation example, the communication flow for the migration destination VM is set to the OFS 4 i at the step of the migration preparation processing. Thus, the packet data for the migration object VM is duplicated and is transferred to both of the migration source VM and the migration destination VM. In the first implementation example, because the communication flow for the migration destination VM is set after the memory image transfer processing of the migration object VM, the packet loss would sometimes occur in the period from the stop of the migration destination VM to the setting of the communication flow for the migration object VM (switching of the access destination to the migration object VM). However, in the second implementation example, because both of the flow for the migration source VM and the flow for the migration destination VM are set in the step of the migration preparation, the occurrence of the packet loss when switching the access destination to the migration destination VM can be prevented.
FIG. 31 is a sequence diagram showing the migration preparation processing in the migration processing by the virtual machine at the step S 685 shown in FIG. 18B in the second implementation example. Referring to FIG. 31 , in the migration preparation processing of the second implementation example, the processing of the step S 684 and S 104 to S 110 is first carried out, like the first implementation example. In the second exemplary embodiment, the OFC 3 sets a communication flow for the migration destination VM to each OFS 4 i in the migration preparation processing (Step S 401 to S 403 ). In detail, the OFC 3 extracts the OFS 4 i and nodes on the communication route for the migration destination VM which is selected based on the communication route data 336 and the topology data 335 and selects the communication flow for the migration destination VM corresponding to each of the communication flows. Then, the OFC 3 issues the setting instruction of the communication flow for the migration destination VM which is selected every OFS 4 i (Step S 401 ). The OFS 4 i sets the transmitted communication flow for the migration destination VM to its own flow table 343 in response to the setting instruction of the communication flow for the migration destination VM (Step S 402 ). When the setting of the flow is completed, the OFS 4 i notifies the flow setting completion report to the OFC 3 (Step S 403 ). The setting data 446 of the communication flow for the migration destination VM set to the OFS 4 i is set to the “already set” or “valid” state.
When the setting of the communication flow for the migration destination VM is completed, the OFC 3 reports that the migration preparation processing is completed, to the integrated management apparatus 1 (Step S 405 ).
As mentioned above, in the migration preparation processing of the second exemplary embodiment, the transfer route of the memory image of the migration object VM and the setting of the flow for controlling the migration, and the setting of the communication route for the access to the migration destination VM and the setting of the flow for controlling the communication are carried out. In the second exemplary embodiment, when the setting of the memory image transfer flow and the communication flow for the migration destination VM to the OFS 4 i are completed, the migration preparation processing is completed.
Referring to FIG. 29 , in the image transfer processing of the second implementation example, the processing (memory image transfer processing) at the step S 686 and the steps S 202 to S 207 is first carried out, like the first exemplary embodiment. When the access to another virtual machine other than the migration object VM (e.g. the data transfer) occurs during the memory image transfer processing, the OFS 4 i according to the access executes the action (for example, the relay processing of data) corresponding to the header data of the reception packet according to the flow set to its own flow table 343 . In this case, by setting the memory image transfer route so as not to hinder the access to the other virtual machine not related to the migration, the migration object VM can be migrated without hindering communication with the other virtual machine.
On the other hand, when the access to the migration object VM occurs during the memory image transfer processing (for example, when data for the migration object VM is transferred), the OFS 4 i on the communication route to the migration object VM executes the action (for example, are the relay processing of data) corresponding to the header data of the reception packet according to the flow set to its own flow table 343 . In the present exemplary embodiment, because the flow is set, supposing that the migration object VM is operating on the VMM 10 and the VMM 20 , the data for the migration object VM is copied and is transferred to both of the migration object VM (migration source VM) on the physical server 5 and the migration destination VM generated on the physical server 6 . The migration source VMM 10 stores the memory page of the migration object VM in the data for transferred migration object VM. At this time, the transferred data for migration object VM is stored in the memory page of the migration destination VM, in the migration destination VMM 20 , too.
During the memory image transfer processing, the memory page is sometimes changed due to the process processing by the migration object VM and the data which is transferred for the migration object VM. The changed memory page is stored in the changed page record area of the storage unit as a copy object (Step S 208 ). It is desirable that the record processing of a changed page is carried out until the migration destination VM starts the operation.
Since then, the same processing as in the first implementation example is carried out from the record (Step S 208 ) of the changed page to the operation (Step S 216 ) of the migration destination VM.
As mentioned above, in the migration method of the second implementation example, the transfer of the memory image of the VM is carried out by using the route (memory image transfer route) which is specified by the integrated management apparatus 1 , like the first implementation example. At this time, because the access to the migration source VM is carried out according to the flow set to the OFS group 4 before the migration processing, the memory image of the VM can be transferred without stopping the communication with the migration source VM. Also, because the memory image transfer route can be optionally set by the integrated management apparatus 1 , the route can be selected so as not to obstruct the communication with the other virtual machine. Thus, the transfer of the memory image which does not influence the communication with the other virtual machine becomes possible.
FIG. 32 is a sequence diagram showing the access destination switching processing in the second implementation example in case of the migration processing of the virtual machine. Referring to FIG. 32 , in the access destination switching processing of the second implementation example, the channel selection processing at steps S 301 to S 301 is first carried out, like the first implementation example. Next, because the setting processing (Steps S 304 to S 307 ) of the communication flow for the migration destination VM to the OFS 4 i which is carried out in the first implementation example is executed in case of the migration preparation processing, the description is omitted in the second implementation example.
Since then, the processing is carried out from the generation processing (Step S 308 ) of the flow to connect between the migration destination VM and the virtual switch 21 to the flow setting processing (Step S 316 ), like the first implementation example.
As mentioned above, in the second exemplary embodiment, when in the migration preparation processing, both of the flow for the migration source VM and the flow for the migration destination VM are set. Therefore, the data transferred for the migration object VM reaches the migration destination VM without being discarded in the period from the stop of the migration source VM at the step S 213 to the flow setting at the step S 316 . In this way, in the computer system of the present exemplary example, the packet loss in the migration of the virtual machine can be prevented. Also, it is never conscious of the migration of the virtual machine from the external network 8 .
Moreover, in the second implementation example, the flow (communication flow for the migration destination VM) corresponding to a new communication route (communication route for the migration destination VM) after the migration of the VM is set in the migration preparation processing. Therefore, the time for establishing the new communication route in the second implementation example can be reduced, compared with the first implementation example in which the new communication route is established after detecting the migration of the VM.
The load balancer 9 may change the load assignment such that the processing (access) to the migration source VM is not generated during the migration processing. Thus, because a processing quantity of the record and transfer of the changed page is reduced, the time of the VM migration is reduced. Also, during the transfer of the memory page of the migration object VM, the load to the migration source VM decreases.
In the above, the exemplary embodiments of the present invention are described in detail. Specific configuration is not limited to the above exemplary embodiments. The configuration is contained in the present invention even if there is a change of a range which does not deviate from the point of the present invention. A method of maintenance processing in the first to fourth exemplary embodiments and a method for the VM migration processing in the first to second implementation examples can be applied by technically combining them in a range where there is not contradiction.
In case of the VM migration processing, the OFC 3 carries out the “selection of the communication route for the migration destination VM” and the “confirmation of the change of the migration destination of the VM” by using the MAC address which is notified in the RARP transmission. However, the present invention is not limited to this. When receiving the packet data transmitted by the migration destination VM which is in the operating condition after the migration processing, for example, the OFS 4 i notifies the reception of the first packet to the OFC 3 because the flow (rule) matching to the packet data is not set. At this time, the OFS 4 i notifies the MAC address of the packet data to the OFC 3 . The OFC 3 selects the communication route corresponding to the notified MAC address as the communication route for the migration destination VM and generates the communication flow for the migration destination VM. Or, in the same way, the OFC 3 may extract the communication route having the MAC address acquired from the report of the first packet as the endpoint, and confirm the change of the connection destination of the reception, by detecting that the connection destination of the VM as an endpoint on the communication route and the switch by which the packet data is received are different.
Also, the migration preparation processing of the VM migration processing may be carried out according to a first packet receipt report (RARP detection report) from the OFS 4 i . In this case, the preparation instruction at the steps S 684 and S 685 and the migration preparation processing are omitted.
It should be noted that this patent application claims a priority based on Japanese Patent Application No. 2009-233095, and the disclosure thereof is incorporated herein by reference. | A communication system includes a control device configured to calculate a packet forwarding path and set a flow based on the packet forwarding path in a node, and a plurality of nodes configured to forward a received packet based on a flow set by the control device. The control device, when receiving a detour instruction, calculates a new packet forwarding path which detours a detour target node and sets a flow based on the new packet forwarding path in the plurality of nodes on the new packet forwarding path. | 6 |
The present invention relates to bicycle suspension systems and more particularly to a suspension fork assembly.
BACKGROUND OF THE INVENTION
Various forms of suspension systems have been proposed and developed for bicycles. The most common form of fork suspension system for bicycles is similar to that used on motorcycles and comprises a pair of telescoping assemblies between which the front wheel is mounted. Each telescoping assembly comprises an outer tube, and inner tube which is free to move in and out of the outer tube and is cushioned in some manner, as by springs and/or a hydraulic system. Generally, the outer tubes are connected at the lower ends to the axle of the front wheel of the bicycle, and the upper ends of the inner tubes are connected together in a fashion similar to the usual upper end of a bicycle fork and extend into the head tube of the bicycle frame. A number of examples of suspension forks for bicycles are shown in the February 1991 issue of Mountain Bike Action, particularly beginning at page 32 thereof. Other bicycle suspension arrangements comprise a single telescoping assembly coupled between the front wheel fork and the head tube of the bicycle frame. In either form of suspension, bushings usually are provided between the telescoping tubes to reduce friction.
Riders have found that suspension front forks can benefit handling and improve control, and a front suspension helps the front wheel follow the ground. A front suspension system is desirable for absorbing bumps, and can enable the bicycle to handle better at higher speeds and be more controllable under rough conditions. Although the front suspension systems of many motorcycles provide these features for motorcycles, they are bulky and heavy, and the designs thereof are not readily adaptable to bicycle use.
Several prior art examples of front suspension systems for bicycles are shown in Horack U.S. Pat. No. 689,970 and Moulton U.S. Pat. No. 3,208,767. The Horack system provides a spring suspension, and includes a ball bearing system for allowing both an axial telescoping action and a rotary steering action. The Moulton patent discloses a spline-type spring suspension. Other suspension systems of interest are shown in Thoms U.S. Pat. No. 723,075, Hutchins U.S. Pat. No. 2,477,748, Ryan U.S. Pat. No. 3,301,575, Hornsby U.S. Pat. No. 3,459,441, Zenser U.S. Pat. No. 3,964,765, Hartman U.S. Pat. No. 4,815,763, British Specification U.S. Pat. No. 295316 of Nov. 1928, and Italian Patent No. 416,260 of Nov. 1946.
As is known to those skilled in the art, any form of system using anti-friction bushings and the like have undesirable static friction called "stiction." Because of this, suspension systems using such bushings tend to stick and then suddenly release or move, and the point at which they release gets higher with higher loads (e.g., a higher radial load caused by a braking load). The dual telescoping assembly presently used on some bicycles is essentially an adaptation of motorcycle front suspension technology; however, in addition to the weight and bulkyness problems, the two telescoping assemblies also have to be fixed together in some manner, as through a "U " shaped yoke at the upper ends of the tubes to eliminate the attendant twisting problem that occurs with each telescoping assembly. This generally is not a problem with motorcycles because the suspension fork assembly can be large and bulky so as to overcome this twisting problem. Additionally, there are linkage type systems, such as the aircraft landing gear scissors link, but this involves an additional coupling with its attendant weight, size and complexity.
It is desirable to provide a front suspension system or suspension fork for bicycles, and particularly for light weight bicycles, which can bear a combination of loads comprising very high radial loads (e.g., from front to back) occasioned by braking, bumps and the like, while at the same time providing stable and tight rotational motion in steering of the front wheel through the suspension system from the handlebars.
SUMMARY
The present invention provides an improved form of suspension system in the form of a suspension fork assembly for bicycles. The assembly comprises first and second steer tubes, one fitting and telescoping within the other, with one being coupled at an upper end to a handlebar stem of the bicycle, and the lower end of the other being coupled to the bicycle fork which receives the front wheel of the bicycle. These tubes are mounted in the head tube of the frame of the bicycle, and include a shock absorbing system within these tubes such as an oil-filled spring dampened internal shock absorbing element or system.
Of particular importance are axially extending longitudinal flat sections or "flats" which are provided on opposing surfaces between the two tubes, along with a plurality of free floating needle bearings disposed on these flat sections to all but eliminate stiction. For example, the upper tube is an outer steer tube coupled to the handlebar stem, and the inside surface of this tube has a plurality, preferably four, of longitudinal flat sections provided therein. The lower tube has a like plurality of similar flat sections, and a plurality of needle bearings are arranged normal to the longitudinal axis of these tubes and suitably supported, so that the lower, inner tube can freely telescope in and out of the upper tube to provide the shock absorbing action. In addition to providing minimum friction between the two tubes, the flats and plurality of needle bearings serve to maintain the fixed relationship between the two tubes, and thus between the handlebars, fork and wheel, and function to transmit the torsional or rotary steering action from the handle bars to the fork and front wheel. While some arrangements have been proposed in the past using a plurality of ball bearings between inner and outer members of a suspension system, it has been found that the use of races with ball bearings is not satisfactory for carrying the various radial and torsional loads that occur.
Accordingly, it is a principal object of the present invention to provide a new form of telescoping suspension assembly for a fork.
Another object of this invention is to provide a new form of suspension assembly for bicycles.
A further object of this invention is to provide a bicycle fork suspension assembly which uses a plurality of needle bearings disposed between flat surfaces of mating telescoping tubes.
These and other objects and features of the present invention will become better understood through a consideration of the following description taken in conjunction with the drawings in which:
FIG. 1A is a simplified exploded perspective view illustrating a preferred form of suspension fork according to the present invention and FIG. 1B is a detailed view of a portion of the suspension fork of FIG. 1A;
FIG. 2 is a detailed assembly drawing of an embodiment of the present invention, illustrating inner and outer steer tubes and sets of needle bearings arranged therebetween;
FIG. 3a is a view of the inner steer tube of the assembly of FIG. 2, and FIGS. 3b and 3c are respective end views thereof;
FIG. 4a illustrates the outer steer tube of the assembly of FIG. 2, FIG. 4b is an end view and FIGS. 4c-4d are cross-sectional views taken along respective lines 4c-4c and 4d-4d thereof, and these views illustrate an adjustable race arrangement;
FIG. 5a is a view of a bearing cage of the assembly of FIG. 2, and FIGS. 5b-5d are cross-sectional views taken along respective lines 5b-5b, 5c-5c and 5d-5d thereof;
FIGS. 6a and 6b illustrate views of a fixed race used in the assembly of FIG. 2;
FIGS. 7a and 7b are similar views of an adjustable race used in the assembly shown in FIG. 2;
FIG. 8 is a perspective view of an alternative manner for providing an adjustable race for a suspension fork according to the present invention;
FIG. 9 is a view, similar to FIG. 2, of an alternative suspension assembly which can incorporate an air spring; and
FIG. 10a is a view of a suspension fork race retainer, and FIG. 10b is an end view thereof, for use in the assembly of FIG. 9.
DETAILED DESCRIPTION
Turning now to the drawings, and first to FIGS. 1A and 1B, a bicycle frame 10 is shown (partial) along with a head tube 11. A fork 12 has an inner steer tube 13 affixed thereto and which extends upwardly through the head tube 11 into an upper outer steer tube 14. The upper end of the outer steer tube 14 is connected to a handlebar stem 15 to which handlebars (not shown) are attached. Upper and lower bearings 16 and 17 can be provided to journal the tube assembly 13-14 within the head tube 11 for steering rotation. The assembly of the tubes 13 and 14 is suitably connected together and retained within the head tube 11, and a suitable hydraulic or air shock system is mounted within these tubes 13-14, all as will become apparent subsequently.
The outer wall 20 of the lower or inner steer tube 13 has a plurality of axially extending longitudinal flat surfaces or "flats" 22-25. Preferably four such flats are provided, although three will suffice and a greater number than four can be used. The inner wall 28 of the upper or outer tube 14 has a like set of opposing flats 32-35. These flats on both tubes extend in the axial directions of the tubes. Four sets of needle bearings 36-39 are disposed between the respective flats of the inner and outer tubes 13-14, as generally illustrated in FIGS. 1A and 1B, and these needle bearings are disposed normal or perpendicular to the axial direction of the tubes 13 and 14, or consequently normal to a radial line extending from the center of the tubes. These needle bearings, which are disposed from the top to the bottom of each flat, are retained in a suitable cage (not shown in FIG. 1B) which will be described later.
It will be apparent to those skilled in the art that the needle bearings 36-39 allow the inner tube 13 to freely slide axially or telescope with respect to the outer tube 14. Additionally, the needle bearings, in conjunction with the associated flats on the tubes 13 and 14, enable the steering torsional or rotary action to be imparted from handlebars connected to the handlebar stem 15 via the telescoping tubes 13 and 14 to the fork 12 and consequently to the front wheel (not shown) supported by the fork. The respective flats and needle bearings bear a combination of loads including very high radial loads from the fork 12 during movement over rough terrain and during braking and the like, while still stabilizing a rotational and torsional connection from the handlebars to the fork. No external coupling or linkage is needed to enable transmission of the rotational and torsional forces for steering, and the present suspension assembly can be made sufficiently strong, light and compact such that a single telescoping assembly can be provided for a bicycle fork without requiring a pair of telescoping assemblies. Sufficient longitudinal or axial travel can be provided, such as several inches. The length of the flats establishes the extent of telescoping action of the tubes. This assembly absorbs bumps, facilitates handling the bicycle while riding, is more controllable over rough conditions, and provides a tight positive steering action.
Turning now to an detailed discussion of an exemplary embodiment of a suspension fork according to the present invention, FIGS. 2 through 7 illustrate the details of a preferred construction. FIG. 2 is a cross-sectional view of the entire assembly, and FIGS. 3 through 7 illustrate major components thereof in further detail. FIG. 2 illustrates the inner steer tube 13 disposed coaxially within the outer steer tube 14, and shows two sets 36 and 38 of the four sets (36-39) of needle bearings disposed between these tubes. The upper and lower bearings 16 and 17 also are shown coupled to the tube 14 in FIG. 2, and these bearings support the suspension fork assembly within the head tube 11 of FIG. 1A in a conventional manner. FIGS. 3A-3C illustrates the inner steer tube 13 in detail and FIGS. 4A-4D illustrates the outer tube 14 in detail. FIGS. 5A-5D illustrates a bearing cage 42, four of which are used for holding the respective four sets of needle bearings 36-39 between the tubes 13 and 14. FIGS. 6 and 7 illustrate respective fixed and adjustable bearing races which are mounted Within the outer steer tube 14 as will be discussed in more detail subsequently.
FIG. 2 also illustrates diagrammatically a hydraulic assembly 44 having a shock carriage assembly 45 and associated coil spring 46 and spring sleeve 47. The hydraulic assembly 44 includes a typical piston and valving arrangement (not shown) to provide an adjustable hydraulic shock action between the tubes 13 and 14.
The upper end at the top end as viewed in FIG. 2) of the outer steer tube 14 is threaded as illustrated for receiving an outer tube cap 50 which in turn receives a jack screw 51 held therein by a retainer screw 52. The lower end (to the left in FIG. 2) of the jack screw 51 has a collar 53 threaded thereon and engages an end of the spring 46. The upper end of the shock carriage 45 is threaded into the jack screw 51 and is secured by a nut 54. Although not shown in FIG. 2, the handlebars stem 15 of FIG. 1A is clamped around the upper end 56 of the outer steer tube 14. The jack screw 51 and associated components are adjustable so as to allow the preload of the hydraulic shock assembly to be adjusted, such as to adjust the same for the rider's weight.
The needle bearing cages 42 and needle bearings 36-39 can be retained between the tubes 13 and 14 in any suitable manner. In the exemplary embodiment illustrated in FIG. 2, the upper end of the spring sleeve 47 includes a shoulder 57 against which the upper end of the bearing cages 42 abut, and the lower ends thereof are retained by a lower collar 58 which is threaded onto the lower end 59 of the outer tube 14. A boot 60 may be attached to the collar 58, and a bottom-out bumper 61 can be provided on the inner tube 13, as shown. The boot minimizes collection of dirt and moisture on the lower exposed portion 64 of the tube 13. The lower end 65 of the inner tube 13 is secured to the fork 12 of FIG. 1A in any suitable manner as will be apparent to those skilled in the art.
FIGS. 3A-3C illustrates in detail the configuration of the inner tube 13 and FIGS. 4A-4D illustrates in detail the configuration of the outer tube 14. The inner tube 13 is essentially a hollow cylinder as illustrated in FIGS. 2 and 3, but has formed on its outer wall 20 four axially extending longitudinal flat surfaces, or flats, 22 through 25 as previously discussed with reference to FIGS. 1A and 1B. An exemplary outer diameter of the tube 13 is 1.125 inches and an exemplary length of the tube 13 is 8.17 inches, with the flats being 5.67 inches long and one-half inch wide, and the cylindrical end 62 2.5 inches long. The tube 13 is formed of steel, and can be formed from Nitriloy or equivalent, and with the flats 22-25 being hardened through the use of copper masking techniques as used in the automotive industry. Since this tube 13 is the most highly stressed part of the assembly, it is important that it be formed of a material and in a manner such that it will bend rather than break under high stresses.
The outer tube 14 as shown in FIGS. 4A-4D comprises a hollow cylinder for mounting in the bearings 16 and 17 within the head tube 11 as previously discussed. The inner wall 28 of this tube has formed therein four longitudinally disposed channels 72- 75 as seen in FIGS. 4b-4d. These channels are formed to receive therein the bearing races 80 and 84 shown in FIGS. 6a-6b and 7. The channels 72-25 also have outer walls 72a-b-75a-b (note FIG. 4b) to receive the bearing cages 42. The race 80 shown in FIG. 6 is termed herein a "fixed" race and has a consistent rectangular cross section with parallel sides or faces 81 and 82 as seen in FIG. 6b. Two of these races 80 are disposed in respective channels 73 and 74. On the other hand, each of the longitudinal channels 72 and 75 receives the race 84 of FIGS. 7A-7B which is termed an "adjustable" race. These adjustable races facilitate assembly and provide a way to adjust bearing clearance after assembly as is explained below. An exemplary length for the tube 14 is 7.66 inches and outer diameter of the central portion is 1.5 inches.
It can be seen in FIGS. 4b-4d that the channels 73 and 74 for the fixed race 80 are not only parallel to the axis of the tube 14 but are perpendicular to a radial line extending through the center of the tube 14.
On the other hand, the channels 72 and 75 are disposed at a slight angle (e.g., approximately 4°) with respect to a normal to a radial line. Furthermore, the adjustable races 84 of FIGS. 7A-7B have a similar inclined side or face 85 which mates with the surfaces of the channels 72 and 75 so that the two inclined surfaces (i.e., 72 and 85 and 75 and 85) mate and cooperate to allow radial adjustment of bearing clearance. Note FIGS. 4c and 4d which are cross-sectional views along the lines 4c-4c and 4d-4d of FIG. 4a and illustrate threaded holes 88-91 for receiving set screws (not shown) to allow a small adjustment of the adjustable races 84 in the direction of the arrows 92 and 93 which, as will be apparent to those skilled in the art, causes the inclined surfaces (i.e., 72 and 85 and 75 and 85) to move along one another thereby causing the normal surfaces 86 of the adjustable races to move radially in and out with respect to the axis of the tube 14 so as to take up bearing clearance. The bearing cages 42 and needle bearings are disposed on the races 80 and 84 (one bearing cage 42 and one needle bearing 36 is shown in FIG. 4D for illustration).
FIGS. 5A-5D and particularly FIG. 5A illustrates the bearing cage 42 that can be used to hold each of the sets of the needle bearings 36-39 between the flats 22-25 of the inner steer tube 13 and the flats provided by the normal surfaces 82 and 86 of the respective races 82 and 84. The bearing cage 42 shown in FIGS. 5A-5D may be molded from a suitable thermalplastic material, and has slots 100 for receiving the needle bearings. The cage includes an outer frame structure 101 and 102 and a plurality of cross-members 104 extending therebetween and forming the needle bearing slots or spaces 100. The cross members 104 are configured as best seen in FIG. 5b-5d, and have inwardly curved upper members 106 (FIG. 5c) and inwardly curved lower members 108 (FIG. 5d) for partially encircling the needle bearings and retaining them within the slots 100. In the present exemplary embodiment, each bearing cage 42 supports sixty-six needle bearings in the slots 100.
ALTERNATIVE BEARING ADJUSTMENT
Turning now to an alternative embodiment for adjusting bearing clearance, FIG. 8 shows an upper end of an outer steer tube 14a having four axially extending longitudinal channels 112 through 115. Four adjustable races 118 are secured to an upper collar 119 which in turn can be adjustably connected to a cap 120. The cap 120 can be similar to the outer tube cap 50 of FIG. 2, and the handlebar stem (not shown) can be attached to the upper end of the tube 14a.
The races 118 shown in FIG. 8 have inwardly facing flat faces 118a which are disposed normal to a radial line from the center axis of the tube 14a. An inner tube (not shown) is disposed within the outer tube 14a, with mating flats, along with suitable needle bearings and bearing cages similar to the structures previously described.
The opposite outer surfaces 118b of at least two of the races 118 are inclined from top to bottom wherein the upper end is thicker than the lower end as shown. Two or more of the channels 112-115 can have a similar mating relationship wherein these channels are inclined outwardly from the bottom to the top of the tube 14a. With this construction, movement of the set of races 118 downwardly into the tube 14a against the inclined channels 112-115 causes the inner normal surfaces 118a of the inclined races to move radially inward to thereby accommodate and adjust for bearing clearance. This arrangement provides another way for adjusting or compensating for bearing clearance and thus involves movement of some or all of races 118 in an axial direction for bearing compensation.
ALTERNATIVE EMBODIMENT
FIGS. 9 and 10A-10B illustrate an alternative embodiment which is almost the same as that shown in FIG. 2 but which is designed to accommodate an internal air spring system (not shown). In this embodiment, the inner tube 13 and outer tube 14 are like those shown in FIG. 2. Likewise, the assembly is mounted in bearings 16 and 17, and the assembly contains the same four sets of needle bearings 36-39, only two of which 36 and 38 are seen in this Figure. Like bearing cages 42 also are used, but the upper or right hand ends as seen in FIG. 9 are retained by a cylindrical race retainer 126 and which is shown in greater detail in FIG. 10. This race retainer 126 fits within the upper end of the outer steer tube 14, and has a lower end forming a shoulder 127 against which the upper ends of the bearing cages 42 are retained. The race retainer is retained in the upper end 56 of the tube 14 by a tube cap (not shown) and related components similar to the tube cap 50 of FIG. 2. The lower ends of the bearing cages 42 are retained by a collar 130 similar to the collar 58 of FIG. 2. A boot 132 is provided and is retained by cable ties 133-134.
While embodiments of the present invention have been shown and described, various modifications may be made without departing from the scope of the present invention, and all such modifications and equivalents are intended to be covered. | There is disclosed herein a suspension fork assembly particularly for use with bicycles. The assembly comprises an outer steer tube which is adapted to be mounted in and extend through the head tube of the bicycle frame, and an inner steer tube telescopes within the outer steer tube. A shock absorbing system is provided within the tubes. The inner surface of the outer steer tube and the outer surface of the inner steer tube each have a plurality of axially arranged opposing longitudinal flat sections, such as four on each tube. A plurality of needle bearings are disposed between the tubes on these flat sections. This arrangement, with the needle bearings arranged on the flat sections between the inner and outer tubes, allows the two tubes to freely telescope in and out with respect to one another without any significant static friction, and also serves to transmit the torsional steering force from the outer tube to the inner tube. The needle bearings thus bear radial loads as well as maintain the in line relationship of the outer and inner tubes for rotational forces while allowing the two tubes to freely telescope. | 1 |
This application is a continuation of application Ser. No. 07/798,773, filed Nov. 29, 1991, now abandoned.
BACKGROUND OF THE INVENTION
This invention relates to an operating control device for a winding type induction machine. In particular, it relates to an operating control device for a winding type induction machine wherein a winding type induction machine is operated with secondary excitation control of the secondary current performed using a PWM-controlled inverter.
For example in the most modern hydro-electric power stations, the need for a so-called variable-speed power generating system, wherein the induction machine is operated at the rotational speed at which the turbine efficiency is a maximum with respect to head changes or load changes has increased. In a hydro-electric generator plant with such a variable speed power generation system, a winding type induction machine is operated with variable speed. Such an operating control device for a winding type induction machine is disclosed in the literature: for example the system disclosed in paragraph 96, FIG. 3.2.11 of Collected Research Theses BMFT-FB-T84-154 (1) of the West German Bundesministerium fuer Forschung und Technologie. The system disclosed in this reference is known as a secondary excitation type variable speed power generating system, in which the primary side frequency is controlled to a constant irrespective of changes in rotational speed, by controlling the secondary current of the winding type induction machine using a frequency converter such as a cyclo converter or PWM controlled inverter. This system has the characteristic advantage that the capacity of the converter can be made small, so it can be applied in particular to large-capacity generating plants.
A generating plant is operated as part of a complex transmission system. In this transmission system, the transmission line has inductance, resistance and stray capacitance distributed along it. Shunt reactors and phase-advance capacitors are provided to improve the power factor. The impedance when the transmission system side is seen from the generating plant therefore has a frequency characteristic. Furthermore, when the transmission system is employed it is switched in a complex manner in response to power flow conditions, so this impedance characteristic is not fixed, but varies.
FIG. 1 is a view showing an example of how harmonic components, if such are present in the primary voltage of the induction machine, are transmitted to the output side of the generating plant, i.e. to the transmission system, when the generating plant is being switched into the transmission system.
FIG. 1 shows an example characteristic in which, due to the impedance characteristic of the transmission system, harmonic components present in the primary voltage of the induction machine are amplified with a peak as indicated by point a. This point is called the "antiresonance point" possessed by the transmission system. In a transmission system having such a characteristic, if the primary voltage of the induction machine were to contain even a slight harmonic component coinciding with point a, because of the antiresonance point, this component would be amplified, producing extreme distortion at the output voltage end of the generating plant. It is undesirable to operate the induction machine in such a condition of large voltage distortion, so this situation must be avoided.
The harmonic components contained in the primary voltage of the induction machine are practically proportional to the harmonic components contained in the secondary excitation voltage of the induction machine. If a PWM controlled inverter is used in the frequency converter for secondary excitation, the output voltage waveform of this inverter contains harmonic components, so these harmonic components have an effect on the harmonic components of the primary voltage of the induction machine.
FIG. 2 is a characteristic showing an example of a typical output voltage waveform of a three phase PWM controlled inverter for secondary excitation. In FIG. 2, v2u*, v2v*, and v2w* are voltage commands to the inverter, whose output frequency is f 0 . e s is a modulation triangular wave for PWM control, whose repetition frequency i.e. modulation frequency is f s . Switching elements constituting the inverter are controlled by comparing these voltage commands v2u*, v2v* and v2w* with modulation triangular wave e s , whereupon the fundamental frequency of the output voltage of the inverter is determined by the frequency f 0 of the voltage commands and a typical PWM controlled inverter output voltage is obtained in which the repetition frequency of a pulse train that changes in square-wave fashion is determined by the frequency f s of the modulation triangular wave.
The harmonic components contained in this PWM controlled inverter output voltage vuv are expressed by the following equations, taking the frequency of the modulation triangular wave e s as f s and the frequency of the voltage commands v2u*, v2v* and v2w* as f 0 :
f.sub.H =nf.sub.s ±kf.sub.0
where
n is an integer, 0 to ∞
and k is an integer, 0 to ∞
As is clear for the above equation, the harmonic components contained in this PWM controlled inverter output voltage change depending on both the frequency f 0 of the voltage commands and the frequency f s of the modulation triangular wave. In operation of an ordinary PWM controlled inverter, the frequency f s of the modulation triangular wave is fixed at a constant value, but the output frequency f 0 changes over a wide range, so the harmonic components of the output voltage of the inverter change in a complex manner. Consequently, even in a variable speed generating system, the harmonic components contained in the output voltage change in a complex manner because the frequency of the PWM controlled inverter, which constitutes the secondary excitation power source, is controlled in a manner matching the rotational speed of the induction machine.
Accordingly, in the variable speed generating system employing a PWM controlled inverter, in the variable speed range, the modulation frequency f s of the secondary excitation voltage is determined such that no harmonic component corresponding to antiresonance point a of FIG. 1 is contained in the primary voltage of the induction machine. However, due to demands imposed in use of the transmission system, when operation is performed with the transmission system being switched over, the impedance characteristic of the transmission system changes, causing the antiresonance point to be displaced. This may result in harmonics contained in the primary voltage of the induction machine coinciding with the antiresonance point. In such cases, the distortion of the primary voltage of the induction machine is enormously increased. This may make it impossible to continue operation.
In this respect, in the system disclosed in the literature reference described above, voltage distortion of the primary voltage of the induction machine is not discussed, and, even when the transmission system is being switched over because of power system requirements, no measures are taken to ensure a stable induction machine primary voltage with little distortion. Development of an operating control device for a winding type induction machine wherein control is performed to make the primary voltage of the induction machine stable with little distortion even when the transmission system is being switched over because of power transmission requirements is now therefore being urgently called for.
SUMMARY OF THE INVENTION
The object of this invention is therefore to provide an operating control device and method for a winding type induction machine of extremely high reliability wherein operation can be conducted such as to give a stable voltage with little distortion even when the impedance characteristic of the transmission line is changing in a complex manner due to the transmission system being switched over etc.
The object of this invention as described above is achieved by the means and steps described below.
An operating control device according to this invention for a winding type induction machine wherein operation is performed by secondary excitation control, using a PWM controlled inverter, of the secondary current of a winding type induction machine connected to a transmission system, comprises:
voltage distortion detection means that detects the voltage distortion of the primary voltage of the winding type induction machine;
primary voltage phase detection means that detects the phase of the primary voltage of the winding type induction machine;
rotor phase detection means that detects the rotational phase of a rotor of the winding type induction machine;
secondary voltage phase calculation means that calculates the phase of the secondary voltage of the winding type induction machine based on the primary voltage phase detected by the voltage phase detection means and on the rotor phase detected by the rotor phase detection means;
secondary current control means that calculates a voltage command signal for the PWM controlled inverter based on the secondary current of the winding type induction machine, the current command value, and the secondary voltage phase obtained by the secondary voltage phase calculation means; and
gate control means that outputs to the PWM controlled inverter a gate control signal for performing PWM control by modulating the voltage command signal with a triangular wave of modulation frequency responsive to the magnitude of the voltage distortion signal, by inputting a voltage command signal from the secondary current control means and a voltage distortion signal from the voltage distortion detection means.
An operating control method according to this invention for a winding type induction machine wherein operation is performed by secondary excitation control, using a PWM controlled inverter, of the secondary current of a winding type induction machine connected to a transmission system, comprises:
a step wherein the voltage distortion of the primary voltage of the winding type induction machine is detected;
a step wherein the rotational phase of a rotor of the winding type induction machine is detected;
a step wherein the phase of the secondary voltage of the winding type induction machine is calculated based on the detected primary voltage phase and on the detected rotor phase;
a step wherein a voltage command signal for the PWM controlled inverter is calculated based on the secondary current of the winding type induction machine, the current command value, and the calculated secondary voltage phase; and
a step wherein there is output to the PWM controlled inverter a gate control signal for performing PWM control by modulating the voltage command signal with a triangular wave of modulation frequency responsive to the magnitude of the voltage distortion signal, by inputting the calculated voltage command signal and the detected voltage distortion signal.
An operating control device for a winding type induction machine wherein operation is performed by secondary excitation control, using a PWM controlled inverter, of the secondary current of a winding type induction machine connected to a transmission system, comprises:
primary voltage phase detection means that detects the phase of the primary voltage of the winding type induction machine;
rotor phase detection means that detects the rotational phase of a rotor of the winding type induction machine;
secondary voltage phase calculation means that calculates the phase of the secondary voltage phase calculation means that calculates the phase of the secondary voltage of the winding type induction machine based on the primary voltage phase detected by the voltage phase detection means and on the rotor phase detected by the rotor phase detection means;
secondary current control means that calculates a voltage command signal for the PWM controlled inverter based on the secondary current of the winding type induction machine, the current command value, and the secondary voltage phase obtained by the secondary voltage phase calculation means; and
gate control means that outputs to the PWM controlled inverter a gate control signal for performing PWM control by inputting a voltage command signal form the secondary current control means and a transmission system changeover signal from a power command center and modulating the voltage command signal with a triangular wave of modulation frequency predetermined in accordance with the transmission system changeover signal.
An operating control method according to this invention for a winding type induction machine wherein operation is performed by secondary excitation control, using a PWM controlled inverter, of the secondary current of a winding type induction machine connected to a transmission system, comprises:
a step in which the phase of the primary voltage of the winding type induction machine is detected;
a step in which the rotational phase of a rotor of the winding type induction machine is detected;
a step in which the phase of the secondary voltage of the winding type induction machine is calculated based on the detected primary voltage phase and on the detected rotor phase;
a step in which a voltage command signal for the PWM controlled inverter is calculated based on the secondary current of the winding type induction machine, the current command value, and the calculated secondary voltage phase; and
a step of inputting the detected voltage command signal and a transmission system changeover signal from a power command center, modulating the voltage command signal with a triangular wave of modulation frequency that is predetermined in accordance with the transmission system changeover signal, and outputting a gate control signal for performing PWM control to the PWM controlled inverter.
BRIEF DESCRIPTION OF THE DRAWINGS
In the accompanying drawings:
FIG. 1 is a characteristic given in explanation of the frequency characteristic possessed by a transmission system.
FIG. 2 is a diagram given in explanation of the operation of a PWM controlled inverter.
FIG. 3 is a block diagram showing an embodiment of an operating control device for a winding type induction machine according to this invention.
FIG. 4 is a block diagram showing an example basic layout of gate control means of this invention.
FIG. 4A is a graph showing the characteristics of the function generator.
FIG. 5 is a block diagram showing another example basic layout of gate control means of this invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 3 shows an embodiment of an operating control device for a winding type induction machine according to this invention. In FIG. 3, a winding type induction machine 10 is connected to a transmission system by a main transformer 9. Inductance 2 and stray capacitance 3 are distributed on power system 1 and the system layout is altered by opening and closing a circuit breaker 4.
An operation control device 11 of this invention controls operation of this winding type induction machine 10. In more detail, conversion of the D.C. voltage of a D.C. power source 38 to a prescribed secondary voltage is performed by gate control of a PWM controlled inverter 37. This controls the magnitude and frequency of the primary voltage of induction machine 10 to a constant.
The phase θ 1 of the primary voltage of winding type induction machine 10 is detected by a primary voltage phase detection means 31 of operation control device 11. The rotational phase θ r of the rotor of winding type induction machine 10 is detected by a rotational phase detection means 32.
The deviation between primary voltage phase θ 1 detected by voltage phase detection means 31 and rotational phase θ r detected by rotational phase detection means 32 i.e. secondary voltage phase θ 2 is obtained by a secondary voltage phase calculating means 33. This secondary voltage phase θ 2 indicates the frequency of the secondary voltage of winding type induction machine 10.
Secondary voltage phase θ 2 obtained by this secondary voltage phase calculating means 33 is input into a three-phase to two-phase converter means 351 and a voltage command generating means 354 of a secondary current control means 35.
Three-phase to two-phase converter means 351 converts the three-phase secondary current of the induction machine detected by a current detection means 34 to a two-phase secondary current consisting of active component I2d and reactive component I2q. Secondary voltage phase θ 2 obtained by secondary voltage phase calculating means 33 is used as a calculation parameter in this conversion.
This active component I2d and reactive component I2q of the secondary current calculated by three phase to two phase converter means 351 are input to comparison means 352, where they are compared with predetermined current command values I*2d and I*dq. The active component deviation DELTA I2d and reactive component deviation DELTA I2q respectively are then calculated.
Active component deviation DELTA I2d and reactive component deviation DELTA I2q of the secondary current calculated by comparison means 352 are then input to a calculation means 353 which converts them into the corresponding active component deviation DELTA V2d and reactive component deviation DELTA V2q of the secondary voltage.
Active component deviation DELTA V2d and reactive component deviation DELTA V2q of the secondary voltage calculated by calculation means 353 are then input to voltage command generating means 354. Voltage command generating means 354 converts active component deviation DELTA V2d and reactive component deviation DELTA V2q of the secondary voltage into three phase voltage commands V*2U, V*2V, and V*2W. The frequency of voltage commands V*2U, V*2V, and V*2W is determined using secondary voltage phase θ 2 calculated by secondary voltage phase calculating means 33 as a calculation parameter in the conversion.
Voltage commands V*2U, V*2V, and V*2W from voltage command generating means 354 are input to a gate control means 36. Gate control means 36 also inputs a signal e d indicating the degree of voltage distortion from a primary voltage distortion detection means 30 of induction machine 10.
The voltage distortion e d is mainly effected by the higher harmonic components at the antiresonant frequency of the transmission line (shown in FIG. 1). Other higher harmonic components may be contained but have only slight effect on voltage distortion e d . The value e d is derived as follows: ##EQU1## where: V=V 1 sinωt+V 2 sin2ωt+. . . +Vn sin nωt (with V 2 . . . V n terms being harmonic components)
V 1 =V 1 sin ωt
|V| 2 =|V 1 | 2 +|V 2 | 2 + . . . +|Vn| 2
|V 1 | 2 =|V 1 | 2
e d : Voltage distortion
V: transmission line voltage
V 1 : fundamental wave component of transmission line voltage
The detector 30, for example, can be implemented using the Hewlett Packard HP4195A.
When gate control means 36 inputs voltage commands v2u*, v2v* and v2w* from the voltage command generating means of current control means 35 and voltage distortion signal e d from voltage distortion detection means 30, if the magnitude of voltage distortion signal e d is within a range less than a prescribed value (e d 2), it carries out PWM control with the modulation triangular wave of preset modulation frequency f s . If voltage distortion signal e d is greater than the prescribed value e d 1, it carries out PWM control with modulation frequency f s changed from its pre-set value by an amount responsive to the magnitude of voltage distortion signal e d . An example of the detailed layout of this gate control means 36 is shown in the block diagram of FIG. 4.
Gate control means 36 consists of a modulation frequency setting means 361 that sets modulation frequency f s of PWM controlled inverter 37, a function generating means 362 that inputs the output signal e d from voltage distortion detection means 30, a calculating means 363 that adds the output signal from modulation frequency setting means 361 and the output signal from function generating means 362, a triangular wave generating means 364 that outputs triangular wave e s of prescribed modulation frequency f s based on the output signal from this calculating means 363, and comparison means 120U, 120V, and 120W that output gate signals 121U, 121V, and 121W to PWM controlled inverter 37 by comparing voltage e commands V*2U, V*2V and V*2W from voltage command generating means 354 with triangular wave e s from this triangular generating means 364.
The characteristic of function generator 362 is shown in FIG. 4A. V F , output to calculation means 363, is θ until the e d threshold e, is reached. This is where the magnitude of the distortion e d is greater than the prescribed value.
Triangular wave generating means 364 consists of a pulse generator 111 that generates pulses corresponding to the magnitude of the output signal from calculation means 363, a counter 113 that counts the number of pulses from this pulse generator 11 and a triangular wave generator 115 that changes the modulation frequency f s in accordance with the number of pulses counted by counter 113.
Let us now assume that the distortion of the primary voltage of induction machine 10 is detected by voltage distortion detection means 30. When this happens, a voltage distortion signal e d proportional to this voltage distortion is input to function generating means 362 of gate control means 36.
Modulation frequency f s0 for PWM control of the fixed frequency with which PWM controlled inverter 37 ought to be operated is set in modulation frequency setting means 361 of gate control means 36. However, the function which is set in function generating means 362 is as follows. Specifically, if voltage distortion signal e d is less than the prescribed value, its output signal is set to zero. If voltage distortion signal e d is greater than the prescribed value, its output signal is set to a value proportional to voltage distortion signal e d . Therefore, if voltage distortion signal e d is greater than the prescribed value, triangular wave generating means 364 outputs a modulation triangular wave e s of modulation frequency f s proportional to the output signal of calculation means 363.
The gate signals for PWM control are produced by comparison of this modulation triangular wave e s with voltage command signals V*2U, V*2V, and V*2W performed by comparison means 120U, 120V, and 120W.
Thus, the content of harmonic components in the primary voltage having an antiresonance characteristic of the transmission system can be reduced by changing the gate signal in accordance with the voltage distortion.
In the operating control device of this embodiment, when the magnitude of the voltage distortion of the primary voltage of induction machine 10 exceeds a prescribed value, the frequency f s of modulation triangular wave e s is adjusted in accordance with the magnitude of this voltage distortion. The voltage distortion of the primary voltage of winding type induction machine 10 can therefore be reduced by changing the harmonic frequency components contained in the output voltage of PWM controlled inverter 37. That is, even when the generating plant is switched into a power system wherein a transmission system having an antiresonance characteristic is being switched over in a complex way, operation with small distortion can always be achieved.
FIG. 5 is a block diagram showing another embodiment of gate control means 36. Parts which are the same as in FIG. 4 are given the same reference numerals.
In general, stable operation of a power system is sought to be achieved by suitable switching over of the transmission system performed by monitoring the power flow on the transmission system at a power command center. Thus, the power command center always has under control how the power system is being switched and operated. The switching condition of the transmission system can therefore be advised to every generating plant that is being switched into the power system.
FIG. 5 shows an example layout of gate control means 36 when a generating plant having a winding type induction machine is employed in such a power system. In FIG. 5, reference numeral 130 indicates a transmission system switching signal that is supplied from the power command center; 361A indicates a first modulation frequency setting means; 361B indicates a second modulation frequency setting means; and 365 indicates a switching means that appropriately changes over between the outputs of first and second modulation frequency setting means 361A and 361B in response to transmission line switching signal 130 and delivers the selected output as input to triangular wave generating means 364.
In a gate control means 36 constructed as above, before the transmission line is changed over, changeover switch 365 is changed over to the A side. Power distortion can then be reduced by ensuring that no harmonic component of the primary voltage of induction machine 10 coincides with the antiresonance point of the transmission system, by controlling PWM controlled inverter 37 with modulation frequency f s1 that is set by first modulation frequency setting means 361A. Next, if the transmission system is changed over, transmission line switching signal 130 is input and changeover means 365 is actuated, causing changeover means 365 to be changed over to side B. PWM controlled inverter 37 is then controlled with modulation frequency f s2 that is set by second modulation frequency f s2 of second modulation frequency setting means 361B is set such that no harmonic component of the primary voltage of induction machine 10 coincides with the antiresonance point of the power system, taking into account the transmission system characteristics after the previous switching over of the transmission line. Operation can therefore be continued with little voltage distortion even after switching over of the transmission system. It is also possible to reduce device costs since the voltage distortion detection means 30 of FIG. 3 can be eliminated by using the gate control means 36 of FIG. 5.
As described above, with this invention, the voltage distortion of the primary voltage of a winding type induction machine can be reduced by changing the content of harmonic components of the output voltage of the PWM controlled inverter. This is done by adjusting the modulation frequency that determines the ON/OFF periods of the switching elements of the PWM controlled inverter in response to the magnitude of the voltage distortion, if the detected value of such voltage distortion in the primary voltage of the winding type induction machine exceeds a prescribed value. A stable primary voltage with little voltage distortion can therefore be achieved even when the impedance characteristic of the transmission line is changing in a complex manner due to changeover of the transmission system etc. Hence an operating control device for a winding type induction machine can be provided which is of very high reliability. | This invention proposes an operating control device and method for a winding type induction machine that ensures that the harmonic components naturally present in the primary voltage of a winding type induction machine, do not correspond to the antiresonance point of the impedance characteristic of the transmission system to which the winding type induction machine is connected. Those corresponding harmonic components are eliminated from the primary winding of the winding type induction machine by applying appropriate voltage command values to a PWM controlled inverter if there is distortion of the primary voltage or if the transmission system is being changed over. | 7 |
BACKGROUND OF THE INVENTION
The present invention relates to a tool for machining operations such as grinding, polishing, milling, cutting-off or honing workpieces, particularly for machining workpieces made of metal, where the tool features at least one machining die and where at least the working area of said die consists of a composite material that contains a hard material.
A tool for machining of the aforementioned type is known from the German Patent No. DE-A1 41 06 005. Such tools are used in various applications that basically include the areas of milling, cutting, honing and grinding by means of material removal. Very important in such processes is a precise removal of the material. In addition, such tools should achieve a long service life, that is, it should be possible to use them over a long period with appropriate reproducible and controllable material removal in regard to the desired precision as well. The service life of such tools is basically determined by the hard materials that are present in the working area of the tool. Such hard materials exhibit sharp-edges structures due to the fact that they are crystalline components. Over the duration of machining, this sharp-edged crystalline structure is destroyed such that the abrasive effect of the tool is reduced. Depending on the type of materials being machined with such a tool and, additionally, depending on the machining speed, that is, the speed that the tool exerts on the surface to be machined, and the high temperatures that the tool must withstand, will occur especially in the working area.
The grinding and cutting tool as described in the above referenced German Patent No. DE-A1 41 06 005, includes a substrate body with a synthetic material matrix where the substrate body is carbon fiber enforced. A coating that contains hard materials in the form of diamond or boron nitride abrasive grains in the binding agent is applied to the substrate body itself. An electroplated or electroless deposited metal coating is situated on the substrate body as interim coating between the substrate body and the coating to obtain a better bond of the abrasive coating on the substrate body. The problem with such abrasion tools is that the temperature resistance is limited by that of the synthetic material. The synthetic material tends to become soft or to lose its bonding capacity, especially at high temperature influences, such that, especially at such conditions the inherent stability of the tool can no longer be ensured for precision work. This also results in complicated tool structures, for example, those to manufacture toothings, not being able to be manufactured such that they keep their stability, and thus, their shape, over an extended service life.
The U.S. Pat. No. 4,504,284 discloses a tool with a cubic carrier, where at least one of its edges is built as a cutting edge. The core body or carrier includes a filler material, carbon fibers and carbon black. The at least one cutting edge is located at one edge of the body and consists of diamond or cubic boron nitride crystals and is connected to said carrier body by an interim layer consisting of α- or β-silicon carbide, or mixtures thereof.
The Japanese Patent No. JP-A-06091541 discloses a grinding wheel whose deformation size is to be reduced when it is rotated under high speed (in relation to the centrifugal forces affecting the grinding wheel). For this purpose, the grinding wheel is made by hardening laminated material through epoxy resins and such, after carbon fibers are wound and laminated in the direction of the circumference. Such coiling strengthens the direction of the circumference of the grinding wheel. Due to the use of epoxy resins as a binding agent to harden the carbon structure, this grinding wheel is not designed for, or cannot be used at high temperatures, because an organic binding agent, such as epoxy resin, softens already at relatively low temperatures and thus loses the strength aimed for.
Finally, the U.S. Pat. No. 4,353,953 relates to an integral composite of polycrystalline diamond and/or cubic boron nitride fibers integrally bonded to a substrate supporting phase. The crystals in the phase of the polycrystalline diamond and/or cubic boron nitride are bonded to the phase of the carrier structure by a medium containing silicon carbide and elemental silicon. Thus, the material is present as a two-layer system, namely the crystals, such as diamonds that are bonded to a carrier body using Si and SiC.
SUMMARY OF THE INVENTION
Based on the aforementioned state-of-the-art and the problems associated with it, it is the objective of the current invention to manufacture a tool for machining that exhibits a high temperature stability, thermal shock resistance and damage tolerance and that can be manufactured with the required precision in any shape and dimension for the desired application.
For a tool with the features stated above, the aforementioned objected is achieved in that the composite material is formed of a fiber structure, which is made of generally continuous carbon and/or ceramic material fibers and is formed of a matrix that contains carbon and hard materials, and in that at least the working area, such as the cutting surfaces of a cutting or milling tool, is made of this composite material.
It is preferred that the fiber structure is made in the form of a web, a weave or a knit.
It is additionally preferred that the hard material is basically made using liquid infiltration of metals in situ.
The basic content of the tool is that at least the working area, for example the cutting edge, is made of fiber structure of continuous fibers comprising the basic structure for binding a matrix that contains the abrasive hard material as a significant component. Preferably, these hard materials are made in situ using liquid infiltration of a metal, that is, liquid metal is infiltrated into a defined open pore structure of the carbon-bound fiber structure. Instead of liquid infiltration, the metal can also be infiltrated in gaseous form, for example, by using the gas phase separation method.
Using this procedure, it is then no longer necessary to use, for example, synthetic materials for embedding the hard materials required for the abrasive effect of the tool surface. The fiber structure made of carbon and/or ceramic material has on the one hand the advantage of withstanding the high temperatures that occur during infiltration of the liquid metal into the porous structure, where said temperatures can be in above 1400° C. with the hard materials under consideration, and on the other hand a preform can made of this fiber structure that prior to liquid infiltration of the metal resembles closely the final contours of the tool to be manufactured, even when said tool has complicated surface structures. This structure of the preform made of carbon-bound carbon fibers and/or ceramic fibers forms an extremely stable basic structure that withstands the operating conditions of a machining tool and that permits sufficient free space, in the area of the working surface, such that the hard materials deposited in the matrix are exposed with their sharp-edged, crystalline structures to carry out the removal of material on the workpiece to be machined, yet are still firmly embedded in the matrix. While this fiber structure forms the stabilizing component during manufacturing, during the material removal, that is, the removal on the material to be machined, the stability of said fiber structure is overshadowed when compared to the embedded hard materials. Still, the fiber structure shows its positive quality and effect in that on the one hand the material strength, material rigidity and thermal shock resistance of the material are increased, and on the other hand, the fiber structures exposed on the work surface, that is, the continuous fibers that end in the surface area of the working area, exhibit a brush-type effect caused by the fiber ends passing over the machined surface and by doing so contribute to a certain degree to the removal of the material. The main reason for this defined arrangement of the fiber structure with the aforementioned effect is that the continuous fibers can be oriented in a defined manner in the fiber's structure.
Regarding the aforementioned brush-effect of the fiber structure, the fibers of the tool ending in the surface area of the working area are with their axes preferably oriented such that they exhibit a larger direction component in the direction of the area normal in the surface area of the working area than perpendicular to it. This means that the fibers end bristle-like in relation to the surface, in contrast to a parallel orientation to the surface, with the result that in addition to the brush-type effect the free area between the fibers accounts for a large portion that is filled with the crystalline hard materials.
With regard to the fiber structure it is advantageous if a significant portion of the fibers of said fiber structure is made of carbon; preferred is a portion of 50% to 100% with a fiber structure consisting of pure carbon fibers in many cases offering particular advantages, as will be shown subsequently. The preferred use of a carbon fiber structure is, on the on hand, due to the fact that carbon fibers, in an unprocessed condition, can be easily formed into a fiber structure, for example in the form of webs, weaves or knits, and on the other hand, due to the fact that such a carbon fiber structure after impregnating with a carbon-containing polymer using temperature treatment, can be solidified to an inherently stable prebody. In addition, the carbon fibers can also be partially used to form carbides with the infiltrated, liquid metal. Such metal carbides are the preferred hard materials for achieving the abrasive material removal.
A portion of the hard material should be present in the form of crystalline carbide. Crystalline carbide exhibits very sharp-edged crystal structures such as is conductive to an optimal removal of the material to be machined. The grain size of the crystalline carbide should be between 5 and 100 μm, preferably greater than 10 μm. It has been found that the removal performance in high performance machining is relatively low if the grain size is set too low, while with a grain size above 10 μm, an effect is achieved where the cutting edges continually renew themselves through breaking off of grains resulting in a significant increase in the cutting performance.
The crystalline carbide should be selected from the group silicon, titanium, zirconium, chromium or vanadium carbide. The respective metals, that is, silicon, titanium, zirconium, chromium and vanadium are particularly well suited for the aforementioned liquid infiltration because their melting point is below 2000° C., that is, the melting point of silicon is 1410° C., titanium 1683° C., zirconium 1852° C., chromium 1875° C. and vanadium 1919° C. It has been found that from the aforementioned group, silicon is preferred not only because of its low melting point, but also from the viewpoint that especially when carbon fibers are used for the fiber structure, portions of the silicon form silicon carbide with the carbon fibers such that a high ratio of hard materials can be achieved in the composite body.
Composites of off-grade metals can be used to lower the melting point even further, that is in regard to the liquid infiltration of the liquid metal into the porous structure around the fiber structure during the manufacture of the composite material body, such that eutectic mixtures are formed that do not cause excessive thermal stress to the fibers due to their low melting temperatures and additionally shorten the duration of the entire metal infiltration process. It is preferable to add boron to the metal melts, such as the silicon melt, where the portion of boron should be less than 10% of the entire metal that is deposited in the matrix. With a portion of boron of 3% of the entire metal, the melting point of silicon, for example, can be lowered to below 1385° C. In addition, borides and silicides are created that have a great abrasive effect and the grain growth of the silicon carbide is increased, which means that the removal performance and/or the service life of the tool can be increased.
The fibers of the fiber structure can also be made of non-oxidic, ceramic fibers, such as silicon carbide and/or silicon nitride or of fiber systems that contain silicon, boron, carbon and nitrogen. In the preferred embodiment with silicon carbide and/or silicon nitride fibers, the portion of silicon carbide and/or silicon nitride is between 50% and 100% with regard to the entire fiber structure. The result of using such silicon carbide fibers or silicon nitride fibers in contrast to using carbon fibers is that the potion of hard materials in the composite material is increased just before it is already present in the fibrous form.
The fiber volume content in relation to the unit of volume of the composite material is set to 20 to 70%, preferably to greater than 50%. A high fiber content per unit of volume, preferably in the range of 50% to 70% has the advantage that the result is a dense material with good embedding of the hard materials leading to a high grain-strength limit.
A defined setting of the abrasive properties of the composite material can be achieved by depositing filler materials in the form of powdery hard materials and/or powdery carbon in the matrix of the composite material. It is preferably if each filler component is present in an amount of less than 10 percent in weight of the composite material. Carbon, in powder form, should be deposited in the matrix in a defined portion if metal carbides are to be created, that is, carbon is made available in an amount sufficient to react with the metal deposited by liquid infiltration, for example, silicon to form silicon carbide. However, it is also possible to deposit hard materials in powder form in a specified grain size with a defined distribution in the matrix. By doing so, the hard material content, for example, the silicon carbide content of the composite material can be increased selectively resulting in an increase in the machining performance of the tool. Filler materials that are deposited in the matrix in such a manner should have a grain size in a range of 1 to 100 μm; good abrasive properties are achieved in this grain size range.
If carbon is deposited in the matrix as filler material, the carbon should be present in the form of amorphous carbon. Amorphous carbon is preferred because it has a greater abrasive effect when compared to graphite carbon; in addition, it is conducive to the carbide formation with the metallic materials.
As already stated above, the preferred metal carbide to be used is one that is created by liquid infiltration of the respective metal into the porous structure around the fiber structure under reaction with carbon. The volume portion of the filled fiber structure should be in a range between 5% and 50%, preferably in a range of 15% to 30% in regard to the volume of the composite material. The range between 15% and 30% is preferred because the residual amount of free metal is then limited, a high capillary effect resulting in quick infiltration is achieved, and the reaction with the fibers is also acceptably low.
All types of fibers and modifications, such as high-strength or high-modulus fibers can be used for the fiber structure made of carbon fibers, however, fibers characterized by a tensile modulus of elasticity of 200 GPa to 300 GPa are preferred. Such fibers exhibit a sufficiently high thermal stability both during the manufacture of the composite material under thermal influence and during the use of the tool for machining applications. In addition, the highest fiber strengths of the composite materials were achieved for these carbon fibers. Orientation of the continuous fibers can be in any spatial axis, however, a semi-isotropic design in at least one plane is preferred.
For a full understanding of the present invention, reference should now be made to the following detailed description of the preferred embodiments of the invention as illustrated in the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1A is an over-head view of a one-part milling disc;
FIG. 1B is a section along the cutting line I—I in FIG. 1A;
FIG. 2A is an over-head view of a milling head with a carrier; device and inserted milling cutter;
FIG. 2B is a section along the cutting line II—II in FIG. 2A;
FIG. 3 is a grinding wheel with an outer abrasion ring and an inner carrier disk;
FIGS. 4A, B, and C show cross sections of the abrasion ring of FIG. 3 with various abrasive contours;
FIGS. 5A and 5B show a tapered and a cylindrical grinding stone;
FIG. 6 shows a cutting shaft with several cutting surfaces distributed around the circumference and running in axial direction of the shaft. and
FIGS. 7A and 7B each show a scanning electron microscope image of the composite material subject to the invention in two planes perpendicular to one another, where the cross section in FIG. 7A corresponds to the emphasized areas designated with the letter X in FIGS. 3 and 6, while the image in FIG. 7B corresponds to the areas designated with the letter Y in FIGS. 3 and 6 .
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present invention will now be described with reference to FIGS. 1-7B of the drawings. Identical elements in the various figures are identified by the same reference numerals.
The following processing steps are to used to manufacture tools subject to the invention for machining workpieces as presented in FIGS. 1 to 7 .
To manufacture an abrasion ring 1 , such as is shown in FIG. 3, that after manufacturing, is placed on a carrier disk 2 , that has a hole 3 for inserting a drive shaft, where a mold corresponding to the shape of the abrasion ring 1 is manufactured. A fiber structure, preferably one of carbon, but if required, also of ceramic fibers is formed in this mold. This structure should have a defined two or three-dimensional structure, for example in the form of weaves, knits or webs, where it should be observed that continuous fibers are to be used. Individual layers of fibers are stacked onto each other in an orthotropic manner such that the individual fibers are oriented in a defined manner in relation to the abrasive surface. This means that a high portion of fibers should end in a plane perpendicular to the abrasion surface such that they are positioned in a brush-like manner to the later abrasive surface. In another processing step, this fiber structure is then soaked with carbon-rich polymers, also called precursors. Such soaking of the individual fibers may also occur prior to building the fiber structure, by either soaking the individual fibers or the individual fiber layers in the form of webs, knits and/or weaves. This soaking can be carried out through resin injections, coiling or prepreg technology. Preferably, the carbon content of the polymer should be >30% in regard to the mass after the pyrolysis, which will be referred to again below; this high carbon content will be used to form the required carbides, as will become apparent later. Additional filler materials can be added to this polymer which is used for coating, soaking and embedding (matrix) of the fibers, where said filler materials shall basically consist of hard materials in addition to carbon. These hard materials should be coordinated with those that cause the machining effect. It should be noted that the grain size of these filler materials, in powder form, should be a suitable grain size which should be in the range of 1 to 100 μm. These filler materials can be added to the polymer prior to soaking of the fiber structure, such that a polymer suspension for soaking is provided. With regard to the volume of this suspension, the filler material portion should be <30 percent in volume. The polymer suspension can be injected into the fiber body with a suitable injection pressure of 5 bar and temperature of about 200° C.
After curing, the body created in this manner is subjected to a pyrolysis, preferably under addition of a protective gas, such as nitrogen, without pressure at a temperature of about 800° C. As a result of the pyrolysis, the polymer matrix is converted into amorphous carbon. At the same time, due to the loss of volume, a micro crack structure is formed around the fiber structure with an open porosity that can be adjusted in a suitable manner by the amount and type of injected polymer suspension. The now present preform with the defined micro crack structure has a basic inherent stability and corresponds to the outer dimensions of the abrasion ring 1 to be manufactured, as shown in FIG. 3 .
In an additional processing step, a liquid metal, for example, liquid silicon is infiltrated into this preform. If liquid silicon is used for this infiltration, a temperature of about 1650° C. is set, that is, the infiltration temperature is above the melting point of silicon, which is 1410° C. The infiltration can be controlled if a suitable vacuum is applied during the infiltration such that a very rapid filling of the pores becomes possible. The liquid, infiltrated silicon reacts with the carbon that is present due to the pyrolized resin or through addition, as a filler material in the resin or polymer, to become silicon carbide, which is a suitable hard material to achieve the desired abrasive properties of the tool. The silicon carbide formed in situ exhibits a distinctive crystalline structure. The temperature increase to 1650° C., that is, a temperature above the melting point of silicon, during infiltration is conducive from the aspect of grain growth, because it has been found that the hard material grain should not be too small in order to ensure a defined breaking out, in order to renew the abrasive surface during the operation of the tool through breaking out of hard material grains.
After a holding time of 2 hours at a temperature of 1650° C. a composite material is obtained that exhibits about 60 percent in weight fibers and in the matrix 5 percent in weight carbon, 30 percent in weight silicon carbide and 5 percent in weight silicon. The grain size of the silicon carbide is in a range of 5 to 20 μm and can be increased to about 50 μm by a post heat treatment at about 2000° C.
The silicon melt can be enriched with other suitable additives to form suitable hard materials. A preferred additive is boron especially in an amount of <10% relative to the mass of the silicon. The addition of boron not only reduces the melting point of silicon, which is conducive to a gentle treatment of the fiber structure (low thermal stress), but boron also forms borides with the infiltrated metals, that is, in the case of the infiltration of silicon as the metal, silicon boride and boron carbide are created as hard materials in addition to silicon carbide.
If 3 percent in weight of boron is added to the silicon melt, the melting temperature is reduced to 1385° C. and, as previously stated, a larger silicon carbide grain is created that is larger by a factor of about 10; in addition, the creation of silicon boride and boron carbide has been observed.
The abrasion ring 1 as has been described above in its manufacturing is then clamped, bolted, or in some other manner bonded to the carrier disk 2 as shown in FIG. 3 . For example, a connective coating can be applied between the carrier disk and the carrier ring where the composition of said coating is dependent on the material of the carrier disk 2 . Preferred as a carrier disk is a carbon fiber body that is structured similar to the abrasion ring 1 and that distinguishes itself for instance by its low weight, which is advantageous especially considering the rotating mass of an abrasion disk, and furthermore by its resistance to high temperature conditions that the abrasion ring 1 subject to the invention may be exposed to. Finally, an additional advantage of a carrier disk 2 made of a carbon fiber structure is that the abrasion ring 1 is connected to the carrier disk via an interim coating of silicon, which together with the free carbon of the carrier disk 2 is converted to silicon carbide under heat, such that a strong connection is attained between carrier disk 2 and abrasion ring 1 .
FIGS. 1A and 1B show a milling disk 4 with a take-up hole 3 , where said milling disk has several blades 5 distributed over the circumference. This milling disk 4 is manufactured according to a method as explained above using the example of the abrasion ring 1 .
FIGS. 2A and 2B show a milling head 5 exhibiting a carrier body 7 , where individual machining tool parts 8 , each provided with a cutting edge 9 are inserted in said tool parts 8 . The carrier body 7 can be made of a carbon fiber structure corresponding to the carrier disk 2 of the embodiment of FIG. 3, where the individual tool parts 8 are in turn connected to the carbon fiber structure 6 by the described connection technology through, for example, a silicon coating. This connection technology offers the additional advantage that the tool pats 8 can be separated from the carrier body 7 through the application of an appropriate temperature to replace them with new ones in case of wear.
As FIGS. 4A, 4 B and 4 C show, the described method can be used to manufacture very differently profiled working areas of the tool in a defined manner, for example, rounded or tapered, as the FIGS. 4B and 4C clearly indicate. To achieve such a contour of the working area, there is no need to subject the tool manufactured using the method described above to finishing work, because the final contour can already be achieved with very close tolerances through shaping the prebody or the preform. For profiling tools, a precise geometry may be achieved through, for example, diamond tools.
FIGS. 5A and 5B show a tapered and a cylindrical grinding stone 10 that are each attached to a carrier pin 11 . The preferred material for this carrier pin is a ceramic composite material or metal, for example elastic steel. Positive locking and force locking can be accomplished as described above, for example, through a silicon coating or through soldering, where the carrier pin is formed square-like, for example, and inserted into a corresponding hole in the grinding stone 10 .
FIG. 6, which shows a cutting shaft, clearly indicates that also machining tools with large dimensions can be manufactured. This cutting shaft 12 has groove-like indentations 14 running parallel to the rotating axis 13 , where the outer edge of said indentations 14 protrude radially further towards the outside than the other one (comparable to the presentation in FIG. 1 A), where the protruding edge forms a cutting edge. This cutting shaft is also manufactured according to the manufacturing method described above.
FIGS. 7A and 7B show a scanning electron microscope image (SEM image) of the area segments designated in FIGS. 3 and 6 with X and Y, that is, area segments that show the structure of the tool in planes perpendicular to one another.
As the cross-section of FIG. 7A shows, two-dimensional carbon web layers are running along and perpendicular to the sectional plane, where the perpendicular fibers cause the brush-type effect described above. While in the image, the carbon fibers are rendered by the black areas, the white areas represent silicon carbide and residual silicon. The course of the fibers is clearly recognizable from the silicon carbide are embedded in the matrix around the fibers. The images in FIGS. 7A and 7B have a 15× magnification. The layer-like structure of the material formed by the individual layers of the web can be recognized in FIG. 7 A. As already stated, the carbon fiber rovings are oriented in 0° and 90° in relation to the plane of the blade. The material consists of about two thirds carbon and about one third SiC, which depends on the set fiber volume content in the polymer condition, that is the condition where the fibers are embedded into the polymer or precursor or soaked therein.
In contrast, in FIG. 7B, showing the section perpendicular to the cross-section of FIG. 7A, nodes, the web type of the fiber and the close connection between fiber and matrix can be recognized. In the node areas of the fiber rovings, clusters of residual matrix materials may occur, which can be recognized by the larger interconnected white areas. In addition, the web with weft and warp threads, oriented perpendicular to one another, can be seen in FIG. 7 B.
There has been shown and described a novel method and device for manufacturing workpieces or blocks from meltable materials which fulfills all the objects and advantages sought therefor. Many changes, modifications, variations and other uses and applications of the subject invention will, however, become apparent to those skilled in the art after considering this specification and the accompanying drawings which disclose the preferred embodiments thereof. All such changes, modifications, variations and other uses and applications which do not depart form the spirit and scope of the invention are deemed to be covered by the invention which is to be limited only by the claims which follow. | A tool for machining workpieces, specially metal workpieces, by cutting, e.g., grinding, polishing, milling, separating or honing, comprising at least one stock-removing tool portion and whose machining range consists of a composite material containing a hard material. Said tool is characterized in that the composite material is formed by a fiber structure consisting of substantially continuous fibers made of carbon and/or a ceramic material and by a matrix containing carbon and hard material, and is also characterized in that at least the machining range, like the cutting or milling tool, is made of said composite material. | 8 |
PRIORITY
[0001] This application claims priority under 35 U.S.C. § 119 to an application entitled “Uplink Scheduling Method In VoIP” filed in the Korean Intellectual Property Office on Aug. 17, 2004 and assigned Serial No. 2004-64854, the contents of which are incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates generally to an uplink scheduling method in a wireless system, and in particular, to a method of scheduling uplink resources for VoIP (Voice over Internet Protocol).
[0004] 2. Description of the Related Art
[0005] A pressing need exists for a scheduling scheme to efficiently use resources in a wireless system that provides a variety of services with limited resources. It is ideal that unnecessarily allocated resources are quickly returned and re-allocated by scheduling. In addition, a technique for utilizing residual resource saved by reducing the data amount, for other purposes, can be considered.
[0006] There are many conventional uplink scheduling types for VoIP service.
[0007] Major examples are UGS (Unsolicited Grant Service) and rtPS (realtime Polling Service).
[0008] The UGS allocates uplink resources of a fixed size upon user request. The user then sends transmission data to a base station (BS) using the uplink resources. The rtPS allocates required resources in response to a periodic uplink resource allocation request from the user. Thus, the user sends transmission data using resources allocated corresponding to the amount of the transmission data.
[0009] FIG. 1 is a graph illustrating a conventional UGS-based uplink scheduling procedure.
[0010] Referring to FIG. 1 , mobile status is divided largely into a talk-spurt period (ON) and a silence period (OFF) on a time axis. Transmission data packets exist in the talk-spurt period, whereas no transmission data packets exist in the silence period. In the illustrated case of FIG. 1 , resources supporting a maximum rate (Rate 1) are fixedly allocated.
[0011] However, a subscriber station (SS) does not send data using all the allocated resources. Only minimum required resources (e.g. Rate ⅛) are used to maintain the service in silence periods 110 and 118 .
[0012] Even in a talk-spurt period, only part of the allocated resources may be used. That is, the SS sends data packets using the allocated resources fully or partially in the talk-spurt period. For example, data packets are sent at Rate 1 using all the allocated resources in a talk-spurt period 112 . On the other hand, data packets are sent at Rate ½ in a talk-spurt period 114 due to a decrease in the amount of transmission data. In a talk-spurt period 116 , data packets are sent using no more than a quarter of the allocated resources. Then the SS uses the minimum resources in the silence period 118 . The minimum resources are those supporting the minimum rate, Rate ⅛.
[0013] As described above, part of the fixedly allocated resources become residual resource in the periods 114 , 116 and 118 using rates other than the maximum rate. This implies inefficient uplink scheduling. As a result, uplink resources are dissipated in the talk-spurt periods as well as in the silence periods.
[0014] FIG. 2 is a graph illustrating a conventional rtPS-based uplink scheduling procedure.
[0015] Referring to FIG. 2 , the SS sends a resource allocation request to the BS in the rtPS, as indicated by reference numerals 212 to 236 . The BS allocates requested uplink resources to the SS. The SS then sends data packets using the allocated resources, as indicated by reference numerals 210 , 220 and 230 .
[0016] There are three talk-spurt periods 210 , 220 and 230 according to the data rates used. Data packets are sent at Rate 1 in the first talk-spurt period 210 , at Rate ½ in the second talk-spurt period 220 , and at Rate ¼ in the third talk-spurt period 230 . Accordingly, the SS requests different amounts of resources in the talk-spurt periods 210 , 220 and 230 . Transitions from the talk-spurt period 210 to the talk-spurt period 220 and from the talk-spurt period 220 to the talk-spurt period 230 occur due to the decrease of data rate in the MS.
[0017] To be more specific, upon generation of data packets in a silence period, the SS requests resource allocation in step 212 . The BS allocates maximum resources to support a maximum data rate (e.g. Rate 1). The SS sends data packets at Rate 1 using the allocated resources. The data transmission at Rate 1 is repeated in the talk-spurt period 210 .
[0018] As the data rate changes due to the decrease in the amount of transmission data in the talk-spurt period 210 , the SS requests resource allocation supporting a decreased data rate, Rate ½ in step 222 . Then, the SS sends data packets using resources allocated by the BS. The data transmission at Rate ½ is repeated in the talk-spurt period 220 .
[0019] If the data rate is to be further reduced in the talk-spurt period 220 , the SS requests resource allocation supporting a decreased data rate, Rate ¼ in step 232 . Then, the SS sends data packets at Rate ¼. The data transmission at Rate ¼ is repeated in the talk-spurt period 230 .
[0020] After the data transmission is completed, the SS operates using minimum resources (e.g. Rate ⅛) in a silence period 240 .
[0021] As noted from the above description, a periodic polling from the SS (i.e. uplink resource requests 212 to 218 , 222 to 226 , and 232 to 236 ) is required in the rtPS. Thus, even in the case where data packets are to be sent using the same resources as indicated by reference numerals 210 , 220 and 230 , the periodic polling 214 to 218 , 224 to 226 , and 234 to 236 is performed. The unnecessary polling leads to dissipation of uplink resources.
[0022] As described above, the UGS and rtPS allocate uplink resources periodically according to their scheduling types irrespective of real-time mobile status. That is, the time-variant mobile status is not reflected in real time in the uplink scheduling. Accordingly, a need exists for developing an efficient uplink scheduling scheme for reflecting mobile status in real time.
SUMMARY OF THE INVENTION
[0023] An object of the present invention is to substantially solve at least the above problems and/or disadvantages and to provide at least the advantages below. Accordingly, an object of the present invention is to provide an efficient uplink scheduling method for VoIP service.
[0024] Another object of the present invention is to provide an uplink scheduling method for minimizing unnecessary resource consumption in allocating uplink resources.
[0025] A further object of the present invention is to provide an uplink scheduling method for preventing an SS from unnecessarily requesting resource allocation to a BS.
[0026] Still another object of the present invention is to provide an uplink scheduling method for allocating optimum resource to support a data rate requested by an SS.
[0027] Yet another object of the present invention is to provide a method of performing uplink scheduling according to a rate-change notification from an SS.
[0028] The above objects are achieved by providing a method of scheduling uplink resources in a wireless communication system supporting VoIP service.
[0029] According to one aspect of the present invention, in a method of scheduling uplink resources in an SS in a wireless communication system supporting VoIP, the SS requests allocation of resources by which to send VoIP data to a BS and is allocated the resources supporting a maximum data rate periodically from the BS. The SS sends the VoIP data at the maximum data rate.
[0030] When requesting the resource allocation, the SS also sends to the BS bandwidth request information requesting continuous allocation of the same resources until the maximum data rate is changed. In response to the resource allocation request, the first resources are allocated before the first resource allocation period comes after reception of the resource allocation request, irrespective of the period.
[0031] According to another aspect of the present invention, in a method of scheduling uplink resources in a BS in a wireless communication system supporting VoIP, the BS receives a resource allocation request for transmission of VoIP data from an SS. In response to the resource allocation request, the BS periodically allocates resources required for data transmission at a maximum data rate from the SS. Along with the resource allocation request, the BS also receives from the SS bandwidth request information requesting continuous allocation of the same resources until the maximum data rate is changed. The first resources in response to the resource allocation request are allocated before the first resource allocation period comes after reception of the resource allocation request, irrespective of the period.
[0032] According to a further aspect of the present invention, in a method of scheduling uplink resources in an SS in a wireless communication system supporting VoIP, the SS requests allocation of resources by which to send VoIP data to a BS. The SS sends the VoIP data at a maximum data rate using resources allocated by the BS. When the data rate is changed, the SS sends to the BS data at the changed data rate, and sends to the BS notification information indicating the rate change using remaining resources. When requesting resource allocation, the SS also sends bandwidth request information requesting continuous allocation of the same resources until the data rate is changed.
BRIEF DESCRIPTION OF THE DRAWINGS
[0033] The above and other objects, features and advantages of the present invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings in which:
[0034] FIG. 1 is a graph illustrating a conventional UGS-based uplink scheduling procedure;
[0035] FIG. 2 is a graph illustrating a conventional rtPS-based uplink scheduling procedure;
[0036] FIG. 3 is a graph illustrating an uplink scheduling procedure according to an embodiment of the present invention;
[0037] FIG. 4 is a diagram illustrating signaling between an SS and a BS for the uplink scheduling according to the embodiment of the present invention;
[0038] FIG. 5 is a flowchart illustrating an operation of the SS for the uplink scheduling according to the embodiment of the present invention; and
[0039] FIG. 6 is a flowchart illustrating an operation of the BS for the uplink scheduling according to the embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0040] A preferred embodiment of the present invention will be described herein below with reference to the accompanying drawings. In the following description, well-known functions or constructions are not described in detail since they would obscure the invention in unnecessary detail.
[0041] In accordance with the present invention as described below, resources are allocated upon receipt of a resource allocation request from an SS. The SS sends data packets using the allocated resources without polling until it changes the resources. Meanwhile, the SS requests continuous allocation of the same resources from a BS without polling. For this purpose, a predetermined pattern is set in the Bandwidth Request field of a Bandwidth Request Header, prior to transmission. In the predetermined pattern, all bits of the Bandwidth Request field are set to 1 s.
[0042] If a data rate-down is required, the SS sends data packets at a decreased data rate and notifies the BS that the resources used are changed due to the rate-down. Thus, the BS can use residual resource saved from the SS for another purpose.
[0043] The SS can notify the BS of a rate change in two ways in the present invention.
[0044] One of them is to add an STI (StaTus Indicator) field to an existing Grant Management subheader format. To apply this method, a bit value indicating a rate change must be defined for the STI field. For example, the bit is set to 1 if the data rate is changed and to 0 if the data rate is kept the same. The STI field is formed by borrowing one bit from a 16-bit PBR (Piggy Back Request) field in the conventional Grant Management subheader. The addition of the STI field results in a 15-bit PBR field. Thus, the following Grant Management subheader format can be proposed as shown in Table 1 below.
TABLE 1 Syntax Size Notes Grant Management subheader ( ) { if (scheduling service type=UGS) { SI 1 bit PM 1 bit Reserved 14 bit Shall be set to zero } Else if (Extended rtPS support && scheduling service type=rtPS) { StaTus Indicator 1 bit PiggyBack Request 15 bit } Else{ PiggyBack Request 16 bit } }
[0045] Table 2 below defines fields used for the embodiment of the present invention among the fields listed in Table 1.
TABLE 2 PBR 15 or PiggyBack Request 16 The number of bytes of uplink bandwidth requested by the SS. The bandwidth request is for the CID. The request shall not include any PHY overhead. The request shall incremental. 15 = Used by the Extended rtPS enabled SS 16 = default PM 1 Poll-Me 0 = No action 1 = Used by the SS to request a bandwidth poll. SI 1 Slip Indicator 0 = No action 1 = Used by the SS to indicate a slip of uplink grants relative to the uplink queue depth STI 1 StaTus Indicator 0 = No action 1 = Used by the SS to indicate a status of data rate decrement.
[0046] In Table 2, the number of the bits in the PBR field is determined according to whether the 1-bit STI field is used or not. When the STI bit is used, the PBR field has 15 bits. In the absence of the STI bit, the PBR field has 16 bits. The STI bit indicates that the data rate is changed. If the STI bit is 0, no action is indicated in relation to a rate change. If the STI bit is 1, a rate change is indicated.
[0047] The other way for the SS to notify the BS of a rate change is to use the PBR field of the existing Grant Management subheader format. For this method, a specific bit pattern must be defined for the PBR field, which indicates a rate change. This bit pattern is different from existing bit patterns used for other purposes. For example, the 16-bit PBR field is set to all Os to indicate a rate change. Table 3 below defines each field in the Grant Management subheader format to implement this PBR-based rate-change notification method.
TABLE 3 Length Name (bits) Description PBR 16 PiggyBack Request The number of bytes of uplink bandwidth requested by the SS. The bandwidth request is for the CID. The request shall not include any PHY overhead. The request shall incremental. 0000000000000000 = In case of the Extended rtPS used by SS to indicate a status of data rate decrement PM 1 Poll-Me 0 = No action 1 = Used by the SS to request a bandwidth poll. SI 1 Slip Indicator 0 = No action 1 = Used by the SS to indicate a slip of uplink grants relative to the uplink queue depth
[0048] A. Scheduling Procedure
[0049] An uplink scheduling procedure proposed by the present invention will be described in detail below.
[0050] FIG. 3 is a graph illustrating an uplink scheduling procedure according to an embodiment of the present invention. Referring to FIG. 3 , mobile status is divided largely into a talk-spurt period (ON) and a silence period (OFF) on a time axis. Transmission data packets exist in the talk-spurt period, whereas no transmission data packets exist in the silence period.
[0051] An SS requests resource allocation from a BS when it transitions from the silence period to the talk-spurt period, as indicated by reference numeral 310 . The resource allocation request is sent using pre-allocated minimum resources. For instance, the SS uses a Bandwidth Request Header to request resource allocation. The Bandwidth Request Header carries bandwidth request information requesting continuous allocation of the same resources even though the SS does not perform polling.
[0052] Table 4 below lists fields in the Bandwidth Request Header and the lengths and characteristics of the fields.
TABLE 4 Length Name (bits) Description BR 19 Bandwidth Request The number of bytes of uplink bandwidth requested by the SS. The bandwidth request is for the COD. The request shall not include any PHY overhead. 1111111111111111111 = In case of the Extended rtPS used by SS to indicate a status of data rate increment CID 16 Connection Identifier EX 1 Always set to zero HCS 8 Header Check Sequence Same usage as HCS entry in Table 5 HT 1 Header Type = 1 Type 3 Indicates the type of bandwidth request header
[0053] The bandwidth request information is delivered in the Bandwidth Request (BR) field. In Table 4, the bandwidth request information is defined as a bit stream of 19 bits being set to all 1 s.
[0054] Upon receipt of the Bandwidth Request Header, the BS periodically allocates resources required for data transmission at a maximum data rate to the SS. The SS sends data using the allocated resources, as indicated by reference numeral 312 . The data transmission is carried out at the maximum data rate, Rate 1 .
[0055] However, the data transmission using the initially allocated resources for the resource allocation request is not periodical. That is, the data transmission using the initially allocated resources occurs between the resource allocation requested time and the first one of periodic data transmissions.
[0056] If a rate change is required while periodically sending data at the maximum rate, the SS sends data at a changed rate in the next transmission interval. The changed rate is lower than the previous rate. In the illustrated case of FIG. 3 , the SS changes its rate from Rate 1 to Rate ½. Meanwhile, the SS sends to the BS notification information indicating the rate change using residual resource saved from the rate-down. The specific methods of sending the notification message using the Grant Management subheader to the BS have been described before. The SS then periodically sends data at the changed rate, as indicated by reference numeral 314 .
[0057] Upon receipt of the notification information in the Grant Management subheader, the BS allocates minimum required resources to support Rate ½ to the SS. The resource allocation accompanying the rate change is performed when needed. That is, if current available resources are sufficient, the BS does not need return allocated resources from the SS in real time.
[0058] If a rate change is required while periodically sending data at Rate ½, the SS sends data at a changed rate, Rate ¼, in the next transmission interval and notifies the BS of the rate change. The SS then periodically sends data at Rate ¼, as indicated by reference numeral 316 . Upon receipt of the notification information in the Grant Management subheader, the BS allocates minimum required resources to support Rate ¼ to the MS.
[0059] If a rate change is required or transmission data does not exist while periodically sending data at Rate ¼, the SS changes the rate to Rate ⅛ for the next transmission interval. Rate ⅛ is assumed to be the lowest rate available to the SS and notifies the BS of the rate change. Then the SS operates normally in a silence period 318 .
[0060] B. Signaling
[0061] Signaling between the SS and the BS in the uplink scheduling of the present invention will be described in detail with reference to the diagram of FIG. 4 . Referring to FIG. 4 , the BS allocates minimum required resources for transmission of a resource allocation request from the SS in step 410 . Typically, resources supporting transmission of 16-byte information suffice for transmission of the resource allocation request from the SS. Because it is assumed herein that the resource allocation request is sent at Rate ⅛, the minimum required resources for the resource allocation request support Rate ⅛.
[0062] In the presence of transmission data, the SS sends to the BS a Bandwidth Request Header requesting resource allocation using the allocated minimum resources in step 412 . A talk-spurt period starts with sending the Bandwidth Request Header. Application of the uplink scheduling according to the present invention needs to be notified by the Bandwidth Request Header. That is, the Bandwidth Request Header carries information indicating that an additional resource allocation request will not be sent until the data rate is changed. For example, the BR field of the Bandwidth Request Header is set to all 1 s.
[0063] Upon receipt of the Bandwidth Request Header, the BS allocates resources by which the SS can send data packets at the maximum data rate, Rate 1 in step 414 . The SS sends data packets at Rate 1 using the allocated resources in step 416 . The resource allocation step 414 and the data transmission step 416 are repeated until the data rate is changed.
[0064] In step 418 , the SS is allocated resources supporting the current rate, Rate 1 by the BS. If the data rate is changed to Rate ½, the SS sends data packets at Rate ½ in step 420 . The SS also sends a Grant Management subheader indicating the rate change from Rate 1 to Rate ½ to the BS. The changed rate is not always indicated by the Grant Management subheader. In other words, the SS notifies the BS of only the rate change by the Grant Management subheader and the BS finds out from the Grant Management subheader that the uplink rate has been changed to a one level-lower rate. The rate change can be indicated by the Grant Management subheader in various ways. The present invention has proposed two main techniques: adding the STI field to the Grant Management subheader, and using the PBR field of the Grant Management subheader. These techniques have been described earlier and their description will not be repeated at this time.
[0065] The BS determines from the Grant Management subheader that the uplink rate has been changed. In step 422 , the BS allocates resources supporting the changed rate, Rate ½. The resulting residual resource supporting up to Rate ½ can be used for other purposes. On the other hand, the resource allocation in step 422 may not be performed immediately after reception of the Grant Management subheader. If the BS has sufficient available resources, it allows the SS to maintain the previous allocated resources. When the residual resource are needed, the BS then re-allocates resources to the SS. Therefore, between steps 420 and 422 , the SS continues sending data packets to the BS using the existing allocated resources. Notably, some resources are saved as residual resource in the SS's data transmission in steps 420 and 422 . However, after the BS allocates resources supporting Rate ½, there are no residual resource produced from data transmission in step 424 .
[0066] If the uplink rate is changed to Rate ¼ with the resources supporting Rate ½ in step 426 , the SS sends data packets at the changed rate, Rate ¼ in step 428 . The SS also sends the Grant Management subheader to the BS, indicating the rate change from Rate ½ to Rate ¼.
[0067] The BS determines from the Grant Management subheader that the uplink rate has been changed. In step 430 , the BS allocates required resources supporting Rate ¼. The resulting residual resource supporting up to Rate ¼ can be used for other purposes. However, the resource allocation in step 430 may not be performed immediately after the Grant Management subheader is received. If the BS has sufficient available resources, it allows the SS to maintain the previous allocated resources. When the residual resource are needed, the BS then re-allocates resources to the SS. Therefore, the SS continues sending data packets to the BS using the existing resources until just before step 430 . In this case, residual resources are produced. However, as the SS sends data packets using resources re-allocated by the BS in step 432 , there are no residual resources produced from the data transmission.
[0068] The BS allocates resources supporting Rate ¼ in step 434 . At the time, the uplink rate is changed to Rate ⅛. Rate ⅛ is the minimum rate that the SS can support. In the present invention, Rate ⅛ is used in a silence period. Therefore, the silence period starts with the rate change to Rate ⅛. The SS can send data using allocated resources or request resource allocation in the silence period. In the illustrated case of FIG. 4 , the SS sends data at Rate ⅛ until just before the SS requests resource allocation in step 444 .
[0069] In step 436 , the SS sends data packets at Rate ⅛ and a Grant Management subheader indicating the rate change from Rate ¼ to Rate ⅛. In the absence of data packets in step 436 , no data transmission is carried out.
[0070] The BS determines from the Grant Management subheader that the uplink rate has been changed. In step 438 , the BS allocates required resources supporting Rate ⅛. The SS sends data packets at Rate ⅛ in steps 440 and 442 .
[0071] The BS allocates required resources supporting Rate ⅛ in step 434 . It is assumed at this moment that transmission data to be sent at an increased rate has been generated in the SS. Therefore, this time becomes the start of a talk-spurt period.
[0072] In step 444 , the SS sends a Bandwidth Request Header to the BS using the allocated minimum resources required to support Rate ⅛. The Bandwidth Request Header carries information indicating that an additional resource allocation request will not be sent until the data rate is changed.
[0073] Upon receipt of the Bandwidth Request Header, the BS allocates resources by which the SS can send data packets at the maximum data rate, Rate 1 in step 446 . The SS then sends data packets at Rate 1 using the allocated resources in step 448 .
[0074] C. Operation in the SS
[0075] FIG. 5 is a flowchart illustrating an operation of the SS for the uplink scheduling according to the embodiment of the present invention. Referring to FIG. 5 , the SS determines the presence or absence of data to be transmitted by VoIP in step 510 . In the presence of transmission data, the SS requests resource allocation to the BS by a Bandwidth Request Header in step 512 . The Bandwidth Request Header carries information indicating that an additional resource allocation request will not be sent until the data rate is changed. For this purpose, the SS can set the 19-bit BR field of the Bandwidth Request Header to all 1 s, for example. Meanwhile, the SS can be allocated resources required for transmission of the Bandwidth Request Header beforehand from the BS.
[0076] After the BS allocates resources, the SS sends data using the allocated resources in step 514 . The allocated resources usually support the maximum data rate available for the SS (e.g. Rate 1).
[0077] The SS continuously monitors the presence of data packets to be sent in step 516 . In the presence of data packets, the SS determines whether the currently allocated resource amount exceeds the amount for transmitting the data, that is, whether the current rate is likely to be decreased in step 518 . If a rate decrement is required, the SS sends the data with in the decreased resource amount, that is, at a changed rate (Rate ½) in step 522 . At the same time, the SS notifies the BS of the resource decrement, that is, the rate change. As stated before, the decrement of resources is indicated by the PBR field or the new STI bit of the Grant Management subheader. The SS then sends data packets at the changed rate in step 514 .
[0078] If the current rate is not determined to be decreased at step 518 , then in step 520 , the SS determines whether are source increase is required. If resource increase is required, the SS requests resource allocation in step 512 . The SS then sends data packets at the maximum rate, Rate 1.
[0079] While not shown in FIG. 5 , even though the SS does not request resource allocation for each data frame transmission, the BS allocates resources to the SS in the previous amount.
[0080] D. Operation in the BS
[0081] FIG. 6 is a flowchart illustrating an operation of the BS for the uplink scheduling according to the embodiment of the present invention. Referring to FIG. 6 , the BS monitors reception of a resource allocation request from the SS in step 610 . For example, the resource allocation request is received by a Bandwidth Request Header. Upon receipt of the Bandwidth Request Header, the BS checks the BR field value of the Bandwidth Request Header. If the BR field value indicates the request of the uplink scheduling proposed by the present invention, for example if the BR field value is set to all 1 s, the BS allocates uplink resources according to the uplink scheduling scheme of the present invention. Otherwise, a typical uplink scheduling method applies, which will not be described herein.
[0082] After allocating resources required to support the maximum allowed rate for the SS in step 612 , the BS receives data transmitted using the allocated resources from the SS in step 614 . In step 616 , the BS monitors reception of a resource decrement request from the SS. If the BS receives the resource decrement request, the BS allocates the resource in an amount indicated by the resource decrement request at step 620 . If the BS does not receive the resource decrement request, the BS determines whether the resource allocation request is received at step 618 . If the resource allocation request is received, the BS allocates the maximum amount of resource available for the SS.
[0083] Upon receipt of the resource decrement request in step 616 , the BS allocates a reduced amount of resources, that is, resources required to support a lower data rate to the SS in step 620 and returns to step 614 where the BS receives data by the SS in the changed amount of resources by the SS.
[0084] On the other hand, if the BS receives the resource allocation request, the BS allocates the resources capable of supporting the maximum data rate in step 612 . While not shown in FIG. 6 , the BS allocates required resources for every data frame.
[0085] In accordance with the present invention as described above, uplink resources are allocated taking into account the uplink rate varying in real time. Therefore, optimum uplink scheduling is carried out. As a result, the following effects are achieved.
[0086] Data transmission efficiency is maximized and the overhead of an SS is reduced. Thus, resource dissipation is prevented.
[0087] Since resources are allocated taking into account the change of the uplink rate of the SS in real time, the resulting saved resources can be utilized for other purposes.
[0088] The SS notifies a BS of a rate change using residual resources saved by reducing the uplink rate. Hence, additional overhead is not produced.
[0089] The number of periodic resource allocation requests transmitted by the SS can be decreased. Therefore, unnecessary consumption of uplink resources for VoIP service can be reduced.
[0090] While the invention has been shown and described with reference to a certain preferred embodiment thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims. | A method of scheduling uplink resources in a wireless communication system supporting VoIP service is provided. A BS allocates an identical amount of the resource continuously until an uplink data rate is changed by an SS's request for a data rate change. When the data rate is changed, the SS reports this event to the BS so that the BS allocates an amount of resource corresponding to the requested data rate. | 7 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention generally relates to agricultural seed planting implements and to the depth-setting mechanism on furrow opening assemblies of such implements, and more particularly to an assembly for adjusting the depth-setting mechanism.
2. Description of the Related Art
Farmers utilize a wide variety of seed planting implements, including seed drills and planters. In a known type of planting implement, seed planting or row units are attached to a toolbar extending transverse to the direction of planting. The toolbar is coupled to a tractor or other work vehicle suitable for pulling the planting implement along a field that is to be seeded to a crop. Each planting unit includes a ground penetrating assembly, often including one or more discs, for opening a seed trench or furrow in the ground as the planting implement is pulled across a field. Components of the ground penetrating assembly shape the bottom and sides of the seed trench, and a seed metering device provides individual seeds at a controlled rate for deposit in the seed trench. Furrow closing components of each row unit close the seed trench in a controlled manner.
It is a desirable and perhaps even primary agronomic principle that seeds should be planted at precisely controlled and consistent depths both within a row and from row to row. Since a single planting implement may be used to plant several different types of crops and/or the same crop in different planting locations under different planting and growing conditions, it is necessary that the planting depth is adjustable so that the seeds are placed at a depth that has been determined to be the best for seed germination and plant growth of the particular crop under the existing and anticipated conditions.
To control planting depth, it is known to provide gauge wheels that travel on the surface of the field to control the depth to which the ground penetrating assembly can run, the positions of the gauge wheels being adjustable so that the depth of the seed trench can be controlled within fractions of an inch. Adjustment linkages are provided for changing the relative positioning of the gauge wheels with respect to the ground penetrating assembly. It is known to move the adjustment linkage by a handle connected thereto, the handle engaging a register having multiple positions for securing the handle to maintain the position to which the handle is adjusted.
As growers have gained greater understanding about seed germination and plant growth, and as soil preparation procedures have changed and improved, crop growers have demanded more precise control over seed placement both in the spacing between seeds and in the depth at which the seeds are placed below the soil surface. Accordingly, there is both a demand and a need for even more precise control over the depth of the seed trench that is formed during planting operations. While depth-setting mechanisms have been designed for ever more precise settings, the linkages and other structures forming the depth setting mechanisms have multiple components and connections which can lead to setting errors due to the variable effects of tolerance stack-up, wear and the like. In planting implements having multiple seed planting or row units, it is necessary that all units be similarly calibrated so that all units plant to the same planting depths when set to the same settings. The multiple components and linkages present in depth-setting mechanisms can acquire unacceptably large variations from one row unit to another in the accumulated stack of tolerances in the component parts even when new, and after wear has occurred and/or if parts have been replaced, planting depths can vary significantly between row units that have been adjusted to the same planting depth settings.
What is needed in the art is a structure for zeroing the depth setting mechanisms in a seed planting implement to adjust out the varying effects of tolerance stack-up and wear between different seed planting units of the implement.
SUMMARY OF THE INVENTION
The present invention provides a seed planting implement with consistent depth setting control for ground penetrating components of the implement by providing an adjustable link in the adjustment mechanism to compensate for the variable effects of tolerance stack-up and wear.
In one form thereof, the invention is directed to an agricultural seed planting implement with a ground penetrating assembly, a depth setting linkage assembly including a control assembly and a depth control linkage arm associated with the ground penetrating assembly and having adjustable positions for changing a depth to which the ground penetrating assembly can operate. The depth control linkage arm is selectively variable in length.
In another form, the invention is an agricultural seed planting implement with a toolbar and a plurality of individual seed planting units connected to the toolbar. Each seed planting unit of the plurality of seed planting units includes a ground penetrating assembly and a depth control assembly for changing a depth to which the ground penetrating assembly can operate. Each depth control assembly is adjustable to a common setting from which depth settings are made for the ground penetrating assemblies.
In a further form thereof, the invention is an agricultural seed planting implement with a ground penetrating assembly, an adjustable gauge wheel supporting said ground penetrating assembly at controlled penetration depths; and a depth control linkage arm adjustably positioning said gauge wheel, said depth control linkage arm having a selectively variable length.
An advantage of the zeroing adjustment for depth control systems disclosed herein is that the penetration depth for seed planting equipment can be more accurately and consistently set across multiple planting units of an agricultural seed planting implement.
Another advantage of the zeroing adjustment for depth control systems disclosed herein is that it compensates for the variable effects of tolerance stack-up and wear.
BRIEF DESCRIPTION OF THE DRAWINGS
The above-mentioned and other features and advantages of this invention, and the manner of attaining them, will become more apparent and the invention will be better understood by reference to the following description of an embodiment of the invention taken in conjunction with the accompanying drawings, wherein:
FIG. 1 is a perspective view of an agricultural seed planting implement;
FIG. 2 is a perspective view of one of the seed planting units of the seed planting implement;
FIG. 3 is a side view of the seed planting unit;
FIG. 4 is another perspective view of the seed planting unit, showing the unit from an angle different from the angle shown in the perspective view of FIG. 2 ;
FIG. 5 is a fragmentary side view of the seed planting unit illustrating inner components used for depth setting;
FIG. 6 is a perspective view a depth setting linkage assembly in the seed planting unit;
FIG. 7 is a side view of the depth linkage assembly;
FIG. 8 is a fragmentary elevation view of the seed planting unit;
FIG. 9 is a cross-sectional view of the seed planting unit; and
FIG. 10 is another perspective view of the linkage assembly as installed and adjusted.
Corresponding reference characters indicate corresponding parts throughout the several views. The exemplification set out herein illustrates one embodiment of the invention and such exemplification is not to be construed as limiting the scope of the invention in any manner.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to the drawings more specifically and to FIG. 1 in particular, a seed planting implement 10 is shown. Seed planting implement 10 has a frame that includes a tow bar assembly 12 having a tow bar 14 and a connection assembly 16 at the longitudinally forward end thereof configured for mating with a corresponding hitch of a tractor or other work vehicle (not shown) for pulling seed planting implement 10 through a field. A laterally extending toolbar 18 is generally transverse to tow bar 14 and thereby generally transverse to the direction implement 10 is towed during planting operations. A plurality of seed planting units (or row units) 20 are connected to toolbar 18 in a side by side relationship, each of the seed planting units (row units) being substantially identical to the others. In the exemplary embodiment shown, seed planting implement 10 includes sixteen seed planting units 20 , only some of which are identified with reference numbers; however, it should be understood that more or fewer seed planting units can be provided on a particular seed planting implement.
Referring now primarily to FIG. 2 through FIG. 5 , each seed planting unit 20 includes a frame 22 that is connected to toolbar 18 by upper arms 24 and lower arms 26 , each arm 24 , 26 being connected to frame 22 and to toolbar 18 . Accordingly, each seed planting unit 20 extends rearward from toolbar 18 to plant a row of seeds as seed planting implement 10 is towed across a field. The individual planting units 20 are spaced along toolbar 18 to provide planted seed rows of a desired spacing. During a planting operation, forward movement of seed planting implement 10 causes each seed planting unit 20 to form a seed trench, deposit equally spaced seeds in the seed trench and close the seed trench over the seeds deposited in the seed trench.
Each seed planting unit 20 includes a ground penetrating or seed trench opening assembly 30 ( FIG. 3 ) having a pair of forwardly and downwardly angled opening discs 32 that converge forwardly and downwardly to open a furrow or seed trench as seed planting implement 10 moves forward. A seed metering system 34 receives seeds from a seed hopper 36 and provides individual seeds at a controlled rate to a seed tube 38 for deposit in the bottom of the seed trench formed. A vacuum system 40 ( FIG. 1 ), which includes a fan 42 and air lines 44 , provides vacuum to seed metering system 34 for the operation of the seed metering system in supplying seeds to seed tube 38 .
A seed trench closing mechanism 50 ( FIG. 1 ) at the trailing end of each seed planting unit 20 closes the seed trench after the seeds have been deposited in the seed trench. Seed trench closing mechanism 50 includes a pair of closing wheels 52 ( FIG. 2 ) that operate on opposite sides of the seed trench to move soil back into the seed trench and over the seeds deposited in the bottom of the seed trench. A trailing press wheel 54 ( FIG. 1 ) travels along the top of the seed trench and firms the soil replaced in the seed trench to eliminate air pockets.
The depth to which opening discs 32 are allowed to penetrate the ground is controlled by a depth control assembly 60 ( FIG. 5 ) that includes a pair of gauge wheels 62 , gauge wheel arms 64 and a depth setting and linkage assembly 80 . One of the gauge wheels 62 is provided adjacent each opening disc 32 . Each gauge wheel 62 is rotatably mounted on one of the gauge wheel arms 64 that are pivotally connected at a pivotal attachment 66 to seed planting unit frame 22 . Each gauge wheel arm 64 has a wheel retention segment 68 extending generally rearward from pivotal attachment 66 and a control segment 70 extending generally upward from pivotal attachment 66 . Pivotal movement of gauge wheel arm 64 about pivotal attachment 66 to frame 22 changes the relative height position of gauge wheel 62 .
A pivoted position to which each gauge wheel arm 64 is placed is controlled by depth setting and linkage assembly 80 having a depth setting control assembly 82 , a depth control linkage arm 84 and a wobble bracket 86 connected to linkage arm 84 by a pivotal connection 88 . Control assembly 82 adjusts an axial position for linkage arm 84 and thereby the position of wobble bracket 86 , with wobble bracket 86 engaging control segments 70 of gauge wheel arms 64 . Raising gauge wheels 62 allows opening discs 32 to penetrate deeper into the ground, and lowering gauge wheels 62 limits the depth to which discs 32 can penetrate into the ground.
Referring now primarily to FIG. 4 through FIG. 6 , control assembly 82 includes a pivot arm 90 of general V-shape, with a pivotal connection 92 at the base thereof to seed planting unit frame 22 . An inner arm 94 of pivot arm 90 has a pivotal connection 96 to depth control linkage arm 84 . An outer arm 98 of pivot arm 90 extends through a depth setting register 100 . Depth setting register 100 defines a slot 102 with a first row of notches 104 along one side of slot 102 and a second row of notches 106 along an opposite side of slot 102 . Opposed pairs of notches including one of the notches 104 and one of the notches 106 define securing locations for securing the position of pivot arm 90 after adjustment thereof.
A handle 108 is provided on the distal end of outer arm 98 and includes laterally projecting position holding pegs 110 , 112 for engaging notches 104 , 106 of register 100 . The pairs of notches including one of the notches 104 and one of the notches 106 secure the position of pivot arm 90 by receiving and engaging pegs 110 , 112 . Handle 108 is mounted on a spring 114 , and can be depressed relative to outer arm 98 such that pegs 110 , 112 disengage notches 104 , 106 by sliding inwardly through the notches so that handle 108 can be moved fore and aft in slot 102 to align pegs 110 , 112 with different pairs of notches 104 , 106 . As handle 108 rebounds outwardly, pegs 110 , 112 slide into the pair of notches 104 , 106 with which the pegs are aligned. Movement of handle 108 fore and aft pivots pivot arm 90 about its pivotal connection 92 , and thereby extends or withdraws depth control linkage arm 84 , to alter the position of wobble bracket 86 , which in turn controls the positions of control segments 70 and thereby the allowable height of gauge wheels 62 .
Depth control linkage arm 84 includes a rearward portion 130 that is connected to pivot arm 90 by pivotal connection 96 , and a forward portion 132 that is connected to wobble bracket 86 by pivotal connection 88 . An intra-link connection 134 between rearward portion 130 and forward portion 132 is axially adjustably so that the overall length of linkage arm 84 is selectively variable. Rearward portion 130 and forward portion 132 are telescopically engaged with one another to accommodate the overall axial adjustability of connection 134 to change the overall length of linkage arm 84 .
Referring now more particularly to FIG. 7 , connection 134 includes a bolt 136 extending through one or more fixed block 138 , 140 fixed between side plates 142 , 144 of forward portion 132 and received by threaded engagement in a threaded block 146 affixed to rearward portion 130 . Bolt 136 includes a shank 150 that is threaded along at least a portion of an end thereof, and a head 152 having a drive configuration 154 ( FIGS. 9 & 10 ) formed therein for engagement by an appropriate tool for rotating bolt 136 . In the exemplary embodiment shown, drive configuration 154 is a hexagonal depression for receiving a hex key (Allen wrench) in rotational drive engagement. It should be understood that drive configuration 154 can be of other shaped depressions in head 152 to engage other internally received drive tools, or drive configuration 154 can be an external shape of head 152 to receive a wrench, drive socket or the like. Head 152 includes opposed external flats 156 , 158 ( FIG. 10 ) that also can receive a wrench, drive socket or the like. Advancing the threaded engagement of bolt 136 into threaded block 146 decreases the overall length of depth control linkage arm 84 , and retracting the threaded engagement of bolt 136 from threaded block 146 increases the overall length of depth control linkage arm 84 .
Referring now particularly to FIG. 10 , a lock mechanism in the form of a bracket or cage 160 is provided to secure the position to which bolt 138 has been adjusted. Cage 160 has sides 162 , 164 and an end 166 . End 166 has a shaped hole 168 therein including opposed flats 170 , 172 to receive and engage head 152 , with flats 156 , 158 of head 152 received against flats 170 , 172 of shaped hole 168 to prevent further rotation of bolt 138 . Sides 162 , 164 of cage 160 are received against side plates 142 , 144 , and together side plates 142 , 144 and sides 162 , 164 form aligned holes 174 , 176 for receiving a pin forming pivotal connection 88 . It should be understood that other structures can be used for preventing the unintended rotation of bolt 136 after the adjustment thereof.
Zero adjustment or calibration of depth control assembly 60 is performed upon initial assembly and can be performed again from time to time as a maintenance procedure. For example, it may be desirable to zero adjust the system after significant wear and/or when replacement parts have been installed. Zero adjustment is performed with wobble bracket 86 , pivotal connection 88 and cage 160 not yet installed (during initial assembly) or removed (when performed as a maintenance step). Seed planting implement 10 is adjusted so that toolbar 18 is elevated, lifting all seed planting units 20 off the ground. As illustrated in FIG. 8 , each gauge wheel 62 drops, pivoting its respective gauge wheel arm 64 about the pivotal attachment 66 thereof until adjustable control segment 70 contacts a frame stop 178 . This allows removal of wobble bracket 86 , pivotal connection 88 and cage 160 when performed as a maintenance operation or the insertion of depth control linkage arm 84 during assembly.
With seed planting implement 10 thus prepared, toolbar 18 is lowered until opening discs 32 barely contact a flat level surface upon which implement 10 is positioned. Opening discs 32 thereby rest at a zero penetration setting, and depth control assembly 60 can be adjusted for proper registration of handle 108 at the zero penetration setting. Control assembly 82 is adjusted such that handle 108 is engaged with the appropriate notches 104 , 106 for a zero penetration setting. Bolt 136 is then adjusted relative to threaded block 146 to advance further into or to withdraw further from threaded block 146 , while at all times remaining threadedly engaged there with. In this way, the overall length of depth control linkage arm 84 is adjusted so that when wobble bracket 86 is re-attached thereto it will properly engage control segments 70 of gauge wheel arms 64 and without unacceptable looseness. It should be understood that the appropriate length for control linkage arm 84 can be determined in numerous ways, including measurement between the end thereof and a fixed point such as, for example, depth setting register 100 or another fixed point of reference. A convenient way for determining the proper overall length of linkage arm 84 is by the use of a gauge 180 . As illustrated in FIG. 9 , gauge 180 includes wings 182 , 184 to be received in wobble bracket slots 186 of control segments 70 . Bolt 136 is rotated so as to advance further into, or withdraw further from threaded block 146 and thereby change the overall length of depth control linkage arm 84 until the outer end of control linkage arm 84 is received at a designated position relative to gauge 180 and wings 182 , 184 are properly received in wobble bracket slots 186 . Bolt head 152 is adjusted as necessary so that flats 156 , 158 thereof are properly positioned such that cage 160 can be installed with shaped hole 168 thereof engaging bolt head 152 , with flats 156 , 158 of bolt head 152 disposed against flats 170 , 172 in shaped hole 168 of cage 160 . Gauge 180 is removed, and cage 160 is installed. Wobble bracket 86 and pivotal connection 88 are installed, thereby securing cage 160 in position and locking bolt 136 against unintended rotation.
When all row units 20 of seed planting implement 10 are adjusted in this manner to a common zero penetration setting, each will have a common elevation relative to the zero setting to which it was adjusted. Each can then be set so that the opening discs 32 thereof will penetrate a same depth into the ground if the control assemblies 82 thereof are adjusted to similar settings in registers 100 . In that way, all row units that are set to the same settings will deposit seeds at the same depths below the surface of the ground.
While this invention has been described with respect to at least one embodiment, the present invention can be further modified within the spirit and scope of this disclosure. This application is therefore intended to cover any variations, uses, or adaptations of the invention using its general principles. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which this invention pertains and which fall within the limits of the appended claims. | A zeroing adjustment for a depth control system of an agricultural seed planting implement has an adjustable link to compensate for the variable effects of tolerance stack-up and wear, so that all planting units of the implement can be adjusted to a common zero ground penetration setting from which depth settings can be made. | 0 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] This invention relates to a system for clearing the reflective surface of an external driving mirror of a vehicle. More particularly, the invention relates to a system and method for blowing compressed air onto side mirrors of a truck in order to clear debris and rain from the mirrors.
[0003] 2. Description of the Related Art
[0004] The accumulation of dirt, precipitation, and/or any other substance on the reflective surface of a motor vehicle's external driving mirror is a common problem for operators of motor vehicles. This accumulation prevents and obstructs the operator's visibility to the rear and side of the vehicle. For example, such accumulation could inhibit the operator's ability to see any traffic approaching in an adjoining lane or any vehicles or other obstructions as the vehicle is traveling in reverse. Moisture will collect on the viewing surface of exterior rearview mirrors in heavy fog or rain. This condition has the ability to distort the reflective properties of the mirror and can be dangerous for a driver. This situation is further compounded during periods of darkness when the reflection of headlights upon the moisture covered rearview mirror creates additional visual distortion to images reflected by the mirror. The situation is most dangerous when the external driving mirrors are the only mirrors on the vehicle that provide the operator with visibility to the rear of the vehicle. Such is the case with many large trucks.
[0005] A number of solutions have been proposed in the prior art to solve the problem of clearing the rear view mirrors of dirt, water, and/or other substances. These solutions include both passive air deflectors and active air blowers. The first group consists of a variety of devices aimed at collecting the incoming air during the movement of a vehicle and projecting it onto the surface of the rear view mirror. Examples of such solutions can be found in U.S. Pat. Nos. 3,598,469; 4,869,581; 4,898,458; 4,903,581; 4,963,011; 4,979,809; 5,179,470; 5,343,328; 5,760,956; 5,815,315; and 5,868,867. These devices may have some use during a high speed movement of a vehicle; however, at low speeds or when the vehicle is not moving, these devices do not provide adequate air flow to clear the mirrors. Also, they are inherently incapable of conditioning the air flow such as to increase its temperature or reduce humidity, all of which may be helpful in extreme weather conditions.
[0006] The use of various active air blowers has also been described. However, many of these systems are overly complex and hence vehicle-specific. They assume incorporation of unique design elements with the on-board air-system of the vehicle and are not easily adapted to be used for a variety of different vehicles. In addition, in many cases the air blowers are underpowered and blow the air at an acute angle towards the surface of the mirror so that the incoming moist and cold air flow simply overwhelms their function. Examples of such devices can be found in the following U.S. Pat. Nos. 3,859,899; 3,877,780; 4,350,084; 4,439,013; 4,462,303; 4,561,732; 4,981,072; 5,383,054; 5,903,389; 5,953,158; and 6,012,817; as well as in a PCT application No. WO 88/00142 and a UK application No. 2,262,441 A.
[0007] Therefore, the need exists for a system for cleaning an external driving mirror of a vehicle that can safely utilize a vehicle's existing air compressing device.
SUMMARY OF THE INVENTION
[0008] Accordingly, it is an object of this invention to provide a system for clearing an external driving mirror of a vehicle that uses the compressed air system of a vehicle.
[0009] It is another object of this invention to provide a system that uses a vehicle's existing compressed air system for the pressure source in conjunction with relatively simple add-on components that do not require extensive retrofitting.
[0010] It is another object of this invention to provide safety mechanisms and features to a system for clearing an external driving mirror of a vehicle that uses the compressed air system of a vehicle.
[0011] In some embodiments, this invention comprises a system for clearing an external driving mirror of a vehicle, wherein said system comprises: an air compressor configured to provide pressurized air to a braking system of said vehicle; an air distribution unit configured to direct compressed air from the air compressor onto a reflective surface of said external driving mirror, and a pressure protection valve disposed between the air compressor and the air distribution unit, wherein said pressure protection valve only provides compressed air to said air distribution unit when the pressure of the pressurized air within the compressor is above a predetermined threshold. Preferably, the vehicle is a truck having an air brake system. Preferably, the system clears both the driving-side and passenger-side external driving mirrors of said vehicle. Preferably, the air distribution unit is a nozzle providing a single stream of compressed air. Preferably, the air distribution unit is disposed on the top of said external driving mirror. Preferably, the air distribution unit directs said compressed air onto the surface of said external driving mirror at an angle of about 60 to about 75 degrees to the reflective surface of the external driving mirror. Preferably, the predetermined threshold is the pressure at which the vehicle's braking system automatically engages the vehicle's brakes. More preferably, the predetermined threshold is about 50 to about 70 PSI.
[0012] In some embodiments, this invention comprises a system for clearing an external driving mirror of a vehicle, wherein said system comprises: a means for supplying compressed air, wherein said means for supplying compressed air also supplies compressed air to a braking system of said vehicle; means for directing said compressed air onto a reflective surface of said external driving mirror; and means for regulating the air flow to the system, wherein said means for regulating ensures that said means for supplying compressed air provides a level of compressed air sufficient to maintain at least a minimum pressure in said vehicle's braking system. Preferably, the vehicle is a truck having an air braking system. Preferably, the system clears both the driving-side and passenger-side external driving mirrors of said vehicle. Preferably, the means for directing said compressed air is a nozzle providing a single stream of compressed air. Preferably, the means for directing said compressed air is disposed on the top of said external driving mirror. Preferably, the means for directing said compressed air directs said compressed air onto the surface of said external driving mirror at an angle of about 60 to about 75 degrees to the reflective surface of the external driving mirror. Preferably, the predetermined threshold is a pressure sufficient to maintain at least a minimum pressure in said vehicle's braking system. More preferably, the predetermined threshold is about 50 to about 70 PSI.
[0013] In some embodiments, this invention comprises an air system for clearing an external driving mirror of a vehicle, wherein said air system comprises: an air compressor; an air distribution unit configured to direct compressed air from the air compressor onto a reflective surface of said external driving mirror, and an activation switch comprising an always-on setting, wherein when said switch is placed in an always-on setting by a user, air from the compressor flows continuously to the air distribution unit until the user places the activation switch in an off position. Preferably, the vehicle is a truck having an air brake system. Preferably, the system clears both the driving-side and passenger-side external driving mirrors of said vehicle. Preferably, the air distribution unit is a nozzle providing a single stream of compressed air. Preferably, the air distribution unit is disposed on the top of said external driving mirror. Preferably, the air distribution unit directs said compressed air onto the surface of said external driving mirror at an angle of about 60 to about 75 degrees to the reflective surface of the external driving mirror. Preferably, the system comprises a pressure protection valve disposed between the air compressor and the air distribution unit, wherein said pressure protection valve only provides compressed air to said air distribution unit when the pressure of the pressurized air within the compressor is above a predetermined threshold.
[0014] In some embodiments, this invention comprises a method of clearing an external driving mirror of a vehicle, said method comprising: providing a flow of compressed air from an air compressor to a reflective surface of said external driving mirror, wherein the air compressor also supplies a pressure of compressed air to a braking system on the vehicle; and stopping the flow of compressed air to the reflective surface when the pressure of air provided to the braking system falls below a predetermined minimum. Preferably, the vehicle is a truck having an air brake system. Preferably, the predetermined threshold is a pressure sufficient to maintain at least a minimum pressure in said vehicle's braking system. More preferably, the predetermined threshold is about 50 to about 70 PSI.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] FIG. 1 is a side view of an embodiment of the present invention as used in a tractor-trailer.
[0016] FIG. 2 is a schematic of an embodiment of the invention connected to a vehicle's air compression system.
[0017] FIG. 3 is a side view of an embodiment of the invention present on an external driving mirror.
DETAILED DESCRIPTION
[0018] Embodiments of the invention relate to a mirror clearing system configured to remove dirt, precipitation, and/or any other substance from a vehicular mirror. Although the present invention can be used in any vehicle having an air compressor or other sufficient source of compressed air, in one embodiment it is used in commercial transport trucks (i.e. trucks having more than two axles), for example tractor-trailers. These larger vehicles typically utilize pressurized air braking systems, which can be configured as part of the mirror clearing system.
[0019] Many vehicles, typically heavy-duty or larger vehicles, use air brake systems. Air brake systems use high pressure air—typically about 100 pounds per square inch (psi)—to apply the brakes. Air is generally supplied by an engine driven air compressor and stored in tanks on the tractor and trailer. When the brakes are applied the air usually comes from the compressed air tanks, which are subsequently recharged by the compressor.
[0020] Generally speaking, in such a system, when the driver depresses the brake pedal to activate the brakes, compressed air is driven through the air lines to a brake chamber. In typical systems the compressed air forces a pushrod out, which through a series of linkages results in the brake linings being forced outward to make contact with the brake drum. This contact with the brake drum is what causes friction that slows the vehicle. In most systems, the vehicle has an application pressure gauge that is viewable by the operator and which shows how much air pressure is being applied.
[0021] An important aspect of most air brake systems is the emergency brake. When the vehicle is driven, the system creates an area of highly pressurized air within an emergency brake chamber. This highly compressed air generally restrains a spring housed inside, which prevents the emergency brakes from engaging. If the pressurized air within the emergency brake chamber falls below a given level, the spring moves outward and causes the emergency brake to automatically engage. Thus, in most systems, if the air pressure within the system falls below a predetermined level, normally about 25-40 pounds per square inch (PSI), the emergency brakes on the vehicle automatically activate and stop the truck from moving.
[0022] One embodiment of the invention is a mirror clearing system for removing water, dirt, leaves and other debris from a vehicle mirror. In use, the system provides a stream of pressurized air to the outer reflective surface of the mirror in order to remove any debris. The mirror clearing system can be activated by a switch located within the cab so that the driver does not need to open a window to activate the system. Additionally, the switch may be an “always on” or “always off” type switch so that once toggled into a position, it stays within that position until actively moved by the driver. In one embodiment, the driver can switch the mirror clearing system on and leave it on while the driver performs a particular activity, such as backing up. This allows the driver to see to the back of the truck, even if it is raining or snowing heavily outside. The stream of air from the system will continually keep the mirror cleared of any water or snow that would fall onto the mirror.
[0023] In one embodiment, the system uses the internal compressed air system that is part of the truck's braking system as its source of compressed air. In one embodiment, a pressure protection valve is provided within the system so that if the air pressure within the braking system falls below a predetermined point, the mirror clearing system will not function. This would prevent the mirror clearing system from reducing the available compressed air even further in instances wherein there may not be enough compressed air to allow the air brakes to properly function.
[0024] FIG. 1 illustrates a perspective view of an embodiment of a mirror clearing system 20 as used in a tractor-trailer 50 . FIG. 1 depicts the tractor-trailer 50 having a compressor 100 providing compressed air to a braking system 200 . The depicted embodiment of the present invention is attached to tractor trailer's existing compressed air system. A pressure protection valve 105 is disposed between the compressor 100 and an air distribution unit 112 which is mounted onto an external driving mirror 114 . The pressure protection valve 105 regulates the amount of air pressure that can pass through the line from the compressor 100 to the air distribution unit 112 . As indicated, the distribution unit 112 communicates compressed air onto a reflective surface 115 of the external driving mirror 114 .
[0025] FIG. 2 provides a more detailed schematic of one embodiment of the present invention. As shown, an air compressor 100 connects to at least one air tank 102 through an air line 101 . The air line 101 also connects the air tank 102 to the vehicle's air brake system 200 . Typically, the compressor 100 maintains a system pressure of about 100 to 125 pounds per square inch (PSI) while in operation within the truck. The compressor 100 delivers pressurized air through line 101 into the air tank 102 so that the air tank 102 maintains a storage of compressed air for use within the braking system 200 and mirror clearing system 20 , as described below. Air line 101 can be made of any material that is adapted to withstand pressures of about 100 to 200 PSI. More preferably, line 101 is made of a plastic resin, such as polyethylene. The air tank 102 supplies compressed air to the rest of the system and is replenished when needed by the compressor 100 .
[0026] It should be realized that it is not necessary for the brake system 200 to connect directly to the air tank 102 . For example, in an alternate embodiment, the brake system 200 and the mirror clearing system 20 each have their own air tank. In this alternate embodiment, each air tank may be filled by the same, or a separate air compressor.
[0027] Optionally, the system may include a filter device 107 or other structure for removing water, oil, and/or other materials from the air provided by the compressor 100 to the air tank 102 . This optional device or structure may be a filter that is installed between the compressor 100 and the air tank 102 . Such a filter 107 may contain a desiccant to aid the removal of water from the system.
[0028] The mirror clearing system 20 can be attached to the vehicle's existing air braking system in any manner so long as the connection retains sufficient air pressure for the brake system to function properly. In one embodiment, the air braking system connects to the mirror clearing system through a “T” push fitting 103 , through, for example part number AQ6. The push fitting connects to the brake system 200 and also to an air pressure protection valve 105 through the line 101 . The line 101 may be made of polyethylene, for example ¼×0.25000×0.170 IDX with a 0.04 inch wall thickness at 200 psi working pressure at 75 degrees Fahrenheit. The line connects to the pressure protection valve 105 via a pressure protection valve input fitting 104 . This pressure protection valve input fitting can be any fitting that is sealingly attachable to the pressure protection valve. In one embodiment, the pressure protection valve input fitting 104 is a fitting having part number AQ92P4XR4.
[0029] Pressure protection valve 105 can be any device or part that is capable of detecting the pressure of air flowing through it and terminating such air flow if the pressure drops below a given threshold. Preferably, pressure protection valve 105 is preset to cut-off air flow at a given threshold. In one embodiment, the pressure protection valve 105 is manufactured by Williams Manufacturing (part number WM778100), Bendix Corp. (part number 227147BXW), or Midland Corp. (part number KN31000). The pressure protection valve is connected to the rest of the system by a pressure protection valve output fitting 106 . This pressure protection valve output fitting can be any fitting that is sealingly attachable to the pressure protection valve. In one embodiment, the pressure protection valve output fitting 104 is a fitting manufactured by Tectran and having part number PL1368-4A. Preferably, pressure protection valve 105 provides a pressurized air flow to the mirror clearing system 20 for clearing one or more external driving mirrors. In one embodiment, the pressure protection valve 105 provides pressurized air until the pressure of the air drops to about 25 to 65 psi. In another embodiment, the pressure protection valve 105 provides pressurized air until the pressure of the air drops to about 50-70 psi. In yet another embodiment, the pressure protection valve 105 provides pressurized air until the pressure of the air drops to about 65 psi. Pressure protection valve output fitting 104 is preferably connected to a toggle switch a 107 line 101 .
[0030] Toggle switch 107 is typically mounted in the cab of a truck to provide convenient access for the driver. The driver can change the toggle switch 107 from an “on” to an “off” position. In one embodiment, the toggle switch 107 provides multiple “on” settings, wherein each setting provides a different level of air flow through the system in order to clear the external driving mirrors. For example, in a first position the switch would provide approximately 50 PSI of air pressure to the external driving mirrors whereas in a second position the switch would provide approximately 75 PSI of air pressure to the external driving mirrors. Of course, the embodiments of the invention are not limited to any particular air pressure level being applied to the external driving mirrors. In one embodiment, the toggle switch 107 has an always-on setting, wherein when said switch is placed in the always-on setting by a user, air from the compressor flows continuously to the air distribution unit until user places the activation switch in an off position. The toggle switch 107 may be part number BA1450 made by Red Dot Manufacturing.
[0031] As described above, toggle switch 107 may be mounted in the interior of the vehicle in such a manner so as to allow the operator of the vehicle to use the switch to turn the mirror clearing system on and off. The toggle switch 107 may be mounted on the dashboard or console on the interior of the vehicle. The mounting of toggle switch 107 may be done using a toggle switch mount bracket 109 . Toggle switch mount bracket 109 can be any bracket capable of mounting a switch in the interior of the vehicle.
[0032] Toggle switch 107 can be connected to the air distribution unit 112 on an external mirror via any method that ensures maintenance of the pressure in the system. If it is desired to apply the system to multiple external driving mirrors, a “T” fitting 110 may be utilized to split the pressurized air from the toggle switch 107 to a plurality of mirrors. Thus, the single system can provide pressurized air to both the driver's side mirror and the passenger side mirror at the same time. In one embodiment, the system provides a toggle switch for each mirror so that the driver can select which mirror to clear without using excess air pressure on a mirror that does not need to be cleared.
[0033] In the embodiment shown in FIG. 2 , The “T” fitting 110 is connected, directly or indirectly, through a pressurized air line to a 90 degree push fitting 111 . In one embodiment, the push fitting 111 is a black plastic elbow fitting having part number 141239. As shown, the push fitting 111 thereafter connects to the air distribution unit 112 in order to provide a stream of compressed air to the mirror 115 . Air distribution unit 112 can be any device or structure capable of directing air onto a surface and air distribution unit 112 can be made from any suitable substance. For example, air distribution unit 112 can be a nozzle providing a single stream of air, a nozzle providing multiple streams of air, multiple nozzles, an open-ended tube, an aperture or slit, or any structure having an opening that permits air to flow through it.
[0034] In one embodiment, the air distribution unit 112 is a nozzle providing a single stream of air. The air distribution unit 112 may be a brass nozzle having part number AQ34-B2. Generally, air distribution unit 112 will distribute air at about 75 to 125 psi to the reflective surface 115 of the mirror 114 . The air distribution unit 112 and 90 degree push fitting 111 are attached to fitting mount bracket 113 , which is mounted to external driving mirror 114 , which has at least one reflective surface 115 . Fitting mount bracket 113 can be mounted to external driving mirror 114 or any other structure that is positioned such that air distribution unit 112 can provide a flow of air to reflective surface 115 . In one embodiment, fitting mount bracket 113 is mounted to the top of external driving mirror 114 . It should be realized that fitting mount bracket 113 is mounted to the top of external driving mirror 114 in such a manner that air distribution unit 112 is aimed at the reflective surface 115 of external driving mirror 114 at an angle θ of about 5 to about 85 degrees. The air distribution unit 112 may, for example, be mounted so as to provide a stream of pressurized air to the reflective surface 115 at angles of about 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, or 85 degrees in some embodiments. It should be realized that the air distribution unit 112 is mounted in one embodiment of the invention so as to provide a stream of pressurized air to the reflective surface 115 at angles of about 60 to about 75 degrees. In another embodiment, the system may provide a pulsatile air flow through the distribution unit 112 .
[0035] FIG. 3 provides a side view of an external driving mirror 114 with an embodiment of the mirror clearing system installed. As indicated, fitting mount bracket 113 is reversibly mounted to the top of external driving mirror 114 in such a manner that air distribution unit 112 is aimed at the reflective surface 115 of external driving mirror 114 at an angle θ. Air distribution unit 112 , in this embodiment comprising a brass nozzle, directs a single stream of air onto the reflective surface 115 of the external driving mirror 114 . As would be expected, the stream of air flows down the reflective surface and removes any type of water, dirt, dust or other debris that may fall onto the reflective surface 115 .
[0036] While plural embodiments of the present invention have been shown and described, it will be apparent to those skilled in the art that many changes and modifications may be made without departing from the invention in its broader aspects. The appended claims are therefore intended to cover all such changes and modifications as fall within the true spirit and scope of the invention. | The present invention comprises a system and method for clearing an external driving mirror on a vehicle. The system and method comprise providing a stream of compressed air to clear water, dirt, and/or other substances from the reflective surface of an external driving mirror. This system uses the air source of the vehicle in conjunction with a safety pressure protection valve. This pressure protection valve will shut down the mirror clearing system in the event that the vehicle's primary air system cannot provide a certain minimum amount of air pressure. | 1 |
This is a continuation of application Ser. No. 017,718 filed on Mar. 5, 1978 now abandoned, which is a continuation of prior filed application Ser. No. 836,270 (now abandoned) filed Sept. 26, 1977 which is a continuation of U.S. Ser. No. 538,674 filed Jan. 6, 1975 and now abandoned, which is a divisional of U.S. Ser. No. 463,956 filed Apr. 5, 1974, which has issued to U.S. Pat. No. 3,908,585.
BACKGROUND OF THE INVENTION
The invention is particularly well suited for use in treating tire cord fabric, especially fabric having warp cords composed of nylon, polyester, or metal. It is desirable coating such tire cords with a substance or agent which promotes the bond between the cords and rubber material used in the production of tires. One such method advantageously employs a liquid solvent as a carrier for bringing the bonding agent into contact with the warp cords. This particular method has never been used to a great extent in the past, because of the high cost of the solvent and the inability to recapture the solvent after deposition of the agent on the warp cords. In some known processes, the tire cord fabric is dipped in a liquid mixture of solvent and agent and then passed into a chamber, filled with solvent vapor, where the fabric contacts hot cans or heated rollers for vaporizing the solvent, carried by the fabric, to dry the fabric. The vaporized solvent is then removed and reconditioned for reuse in the process. Impurities in the solvent mixture react unfavorably when the fabric contacts the hot cans, causing undesirable deposits on the hot cans, necessitating frequent stoppage of the process to clean or replace the contaminated hot cans.
Other methods, more suitable for treating tire cord fabric on a production basis, employ super-heated solvent vapor, rather than hot cans, for contacting the fabric to heat and evaporate the solvent. It has been found that using the latter method increases the rate at which the fabric can be processed which, from an economical standpoint, is very important. Although the use of super-heated solvent vapor produces beneficial results, a highly efficient apparatus for treating the fabric and recovering solvent vapor has not been found. The invention is directed to providing such an apparatus.
Briefly stated, the invention is in an apparatus for treating tire cord fabric. Means are provided for coating the tire cord fabric with a liquid coating comprising a mixture of an agent which promotes the bond between the warp cords of the fabric and rubber material used in the production of tires, and a vaporizable solvent which is a carrier of the agent. A drying chamber is supplied adjacent the fabric coating means and is sealed from the ambient atmosphere and said means. The drying chamber has inlet and outlet openings through which the tire cord fabric passes as it moves into and out of the drying chamber. A condenser is disposed adjacent each of the openings for condensing excess solvent vapor in the drying chamber. Means are provided for filling the drying chamber with a vapor of a solvent similar to the solvent of the mixture. A plurality of vertically elongated plenums are disposed side-by-side in the drying chamber, and a number of vertically spaced nozzles extend from each of the plenums for directing superheated vapor of a solvent, similar to the solvent of the mixture, against tire cord fabric guided past the nozzles. Means are provided for continually removing solvent as a vapor from the drying chamber, and superheating the removed solvent vapor for subsequent passage through the nozzles. Also provided are means for removing the condensed solvent vapor from the drying chamber for reconditioning and reuse in the process, such reconditioning including separating condensed solvent from impurities, such as water, and reusing the purified solvent in a new mixture.
DESCRIPTION OF THE DRAWING
The following description of the invention will be better understood by having reference to the annexed drawing, wherein:
FIG. 1 is a cross-section of an apparatus made in accordance with the invention; and
FIG. 2 is a section of the apparatus viewed from the line 2--2 of FIG. 1.
DESCRIPTION OF THE INVENTION
Referring generally to the drawing, there is shown an apparatus 5 for treating tire cord fabric 6 with a material or agent for increasing or promoting the bond between the warp cords of the fabric 6 and rubber material used in the production of tires. The tire cord fabric 6 is taken from the ambient atmosphere and moved downwardly through an inlet 7 into a long narrow entry compartment 8. The fabric 6 passes through an appropriate flap seal 9 which is provided in the inlet 7 for sealing the entry compartment 8 from the ambient atmosphere.
The tire cord fabric 6 continues downwardly into an enclosed chamber 10 which contains a dip tank 11 filled with a liquid coating 12 composed of a mixture of the agent and any suitable, chemically compatible solvent which, when vaporized, is preferably heavier than air. The dip chamber 10 abuts the entry compartment 8 and is provided with an entrance opening 13 through which the fabric 6 moves from the entry compartment 8 into the adjacent dip chamber 10. An exit opening 14 is disposed in the dip chamber 10 in spaced relation from the entrance opening 13. The entrance and exit openings 13 and 14 are also provided with suitable seals 15 for sealing the dip chamber 10 from the ambient atmosphere and adjacent compartments.
A scraper blade assembly 16, including a pair of similar wiper blades 17 for compressibly engaging the fabric 6, is provided between the dip tank 11 and exit opening 14 for removing excess liquid coating 12 from the fabric 6 shortly after it leaves the dip tank 11. An applicator roll 18 is rotatably mounted in the dip tank 11 and directs the fabric 6 into the liquid coating 12.
The liquid-coated fabric 6 moves from the chamber 10 upwardly through a secondary compartment 19 which is also isolated or sealed from the ambient atmosphere or adjacent processing chambers. The secondary compartment 19 is sufficiently long, giving the liquid coating 12 time to set up on the fabric 6. The fabric 6 passes over a pair of head pulleys or rollers 20 into the main processing chamber 23 where the fabric 6 is heated and dried.
The drying chamber 23, as best seen in FIG. 1, has a greater height measured vertically than a width measured horizontally. Moreover, the upper portion of the drying chamber 23 is generally U-shaped, having a pair of upstanding chimneys which form elongated, restricted throat sections 24 and 25. The throat sections 24 and 25 are provided with inlet and outlet openings 26 and 27 through which the fabric 6 passes as it moves into and out of the drying chamber 23. A seal 28 is provided in each of the openings 26 and 27 for sealing the drying chamber 23 from the ambient atmosphere and adjacent compartments. The seals 28 have a two-fold purpose; namely, to keep air out of the drying chamber 23 and prevent the passage of solvent vapor from the drying chamber 23.
A condenser 29 is mounted in each of the chimneys 24 and 25 for condensing solvent vapor accumulating near the openings 26 and 27 to prevent the escape of solvent vapor from the drying chamber 23. Each of the condensers 29 comprises two sets A and B of plate coils C, between which the fabric 6 is guided. Each of the sets A and B includes, in this embodiment, three separate plate coils C which are vertically mounted in parallel relation such that they laterally fill the chimneys 24 and 25 to more effectively remove excess solvent vapor. A discharge pipe assembly 30 is associated with each set A and B of condensers 29 for receiving condensed solvent vapor and carrying it from the drying chamber 23 to a remote point for reconditioning and recycling. A number of strategically located baffles b are positioned below each of the condensers 29 to reduce the rate at which solvent vapor flows through the condensers 29 to eliminate possible turbulence in the flow of solvent vapor, such that the vapor will contact the condensers 29 more intimately, producing more effective condensation of the vapor in the chimneys 24 and 25.
A boiling sump 31, filled with liquid solvent 32 is provided adjacent the bottom 33 of the drying chamber 23 in spaced relation from the inlet and outlet openings 26 and 27 which are located in the top 34 of the drying chamber 23. The liquid solvent 32 in the boiling sump 31 is the same as that used in the liquid coating 12. Any suitable means are used for heating the liquid solvent 32 in the boiling sump 31 to a temperature sufficient to vaporize the solvent 32 and fill the drying chamber 23 with solvent vapor to eliminate any non-condensable gas, such as air, in the drying chamber 23.
A plurality of vertically elongated heat plenums 35-39 are disposed side-by-side in the drying chamber 23. Each of the plenums 35-39 are preferably wider than the corresponding width of the fabric 6. The adjacent opposing faces 30 and 41 of plenums 35 and 36, faces 42 and 43 of plenums 36 and 37, faces 44 and 45 of plenums 37 and 38, and faces 46 and 47 of plenums 38 and 39, are each provided with a number of nozzles 48 for directing superheated solvent vapor against the fabric 6 moving between the plenums 35-39 and past the nozzles 48. The fabric 6 is directed past the nozzles and between adjacent plenums 35-39 by a number of strategically located rollers 49.
The oppositely faced nozzles 48 of adjacent plenums, as best seen in FIG. 1, are vertically staggered and not directly across from each other. The nozzles 48 are preferably similar in design and formed by horizontally disposed slots or openings 50 which are at least coextensive with the width of the fabric 6 being treated. Deflectors 51 extend from opposing sides of each of the nozzle openings 50 and channel the streams of superheated solvent vapor against the fabric 6 moving between the plenums 35-39.
A portion of the solvent vapor in the drying chamber 23, is forced by strategically located high-powered fans through heat exchangers 52 and 53 (FIG. 2) which are located adjacent the drying chamber 23 and coupled to the plenums 35-39. The heat exchangers 52 and 53 are each provided with steam coils 54 for superheating the vaporized solvent to about 250° F. for circulation to the plenums 35-39. Thus, solvent is continually removed from the drying chamber 23 as a vapor which is immediately superheated and recirculated to the drying chamber 23 for contacting fabric 6 moving through the drying chamber 23. This produces a well-balanced system in which the processing conditions within the drying chamber 23 are easily maintained, since all superheated solvent vapor used in the treatment of the fabric 6 is formed from solvent vapor already in the drying chamber 23.
The superheated solvent vapor impinges against the fabric 6 and flashes off or evaporates solvent carrier on the fabric 6, whereby the fabric is dried and the bonding agent deposited on the fabric. The dried fabric 6 then moves from the drying chamber 23 through the fabric outlet 27 into an adjacent discharge compartment 55 which is also sealed from the ambient atmosphere and drying chamber 23. The discharge compartment 55 is provided with a discharge opening 56 and seal 57 through which the fabric 6 passes as it moves into the ambient atmosphere for winding on a standard take-up device, or into other chambers for further treatment.
The solvent vapor, condensed by the condensers 29, is removed from the drying chamber 23 through the discharge pipe assemblies 30 to a conventional separator where the solvent is separated from impurities, such as water. The purified solvent is then piped to a storage tank for future use in a new mixture of liquid coating, or in the boiling sump 31.
Thus, there is provided an apparatus which is especially suitable for using a solvent in a process for treating the warp cords of tire cord fabric with a bonding agent. The nozzles of the different plenums are in close proximity to the moving fabric, such that the streams of superheated solvent vapor pouring from the nozzles, rapidly flash off the solvent to dry the fabric. The apparatus employs a number of heating plenums in which different processing conditions can be created to vary the treatment of the fabric as it passes adjacent the openings of the nozzles extending from the plenums. Moreover, the drying chamber of the apparatus is designed such that the highly pressurized superheated solvent vapor pouring from the nozzles, is allowed to expand freely in the enlarged upper portion 58 of the drying chamber 23. This has a muffling or baffling effect on the streams of vapor which can cause unwanted currents. These unwanted currents can sweep solvent vapor past the condensers 29 without being condensed. The movement of solvent vapor through the condensers is also slowed appreciably as the solvent vapor contacts the baffles in the chimneys or throat sections 24 and 25 which are small in relation to the enlarged drying or expansion chamber 23 and remove the condensers 29 out of the general flow pattern of the solvent vapor in the drying chamber 23. The configuration of the drying chamber and the particular location of the condensers 29 help in recovering a greater amount of solvent which, because of its cost, is of prime importance. | An apparatus for drying tire cord fabric dipped in a liquid coating containing a vaporizable solvent. The drying chamber of the apparatus includes a boiling sump for filling the chamber with solvent vapor, and a plurality of vertically elongated plenums mounted in side-by-side relation, each plenum having a number of horizontally elongated nozzles in vertically spaced relation. The tire cord fabric is passed adjacent the nozzles and super-heated solvent vapor is forced through the nozzles against the moving fabric to flash off or vaporize the solvent carried by the fabric, thereby drying the fabric. | 3 |
FEDERAL RESEARCH STATEMENT
[0001] This invention was made with Government support under Agreement No. F33615-98-C-2893 awarded by the U.S. Department of the Air Force. The Government has certain rights in the invention.
BACKGROUND OF INVENTION
[0002] 1. Field of the Invention
[0003] The present invention generally relates to protective coating systems for components exposed to high temperatures, such as the hostile thermal environment of a gas turbine engine. More particularly, this invention relates to a combination of a superalloy substrate composition and coating system that exhibits improved spallation resistance of the coating system.
[0004] 2. Description of the Related Art
[0005] Higher operating temperatures for gas turbine engines are continuously sought in order to increase their efficiency. Though significant advances in high temperature capabilities have been achieved through the formulation of nickel and cobalt-base superalloys, certain components of the turbine, combustor and augmentor sections that are susceptible to damage by oxidation and hot corrosion attack are typically protected by an environmental coating and optionally thermal barrier coating (TBC), in which case the environmental coating is termed a bond coat that in combination with the TBC forms what may be termed a TBC system.
[0006] Environmental coatings and TBC bond coats are often formed of an oxidation-resistant aluminum-containing alloy or intermetallic. An example of the former is MCrAlX (where M is iron, cobalt and/or nickel, and X is yttrium or another rare earth element), which is deposited as an overlay coating. An example of the latter includes diffusion coatings, particular diffusion aluminides and platinum-aluminides (PtAl) that contain aluminum intermetallics (e.g., NiAl and PtAl). Other types of environmental coatings and bond coats that have been proposed include beta-phase nickel aluminide (NiAl) overlay coatings. In contrast to the aforementioned MCrAlX overlay coatings, which are metallic solid solutions containing intermetallic phases, the NiAl beta phase is an intermetallic compound that exists for nickel-aluminum compositions containing about 30 to about 60 atomic percent aluminum. Notable examples of beta-phase NiAl coating materials are disclosed in commonly-assigned U.S. Pat. No. 5,975,852 to Nagaraj et al., U.S. Pat. No. 6,153,313 to Rigney et al., U.S. Pat. No. 6,255,001 to Darolia, and U.S. Pat. No. 6,291,084 to Darolia et al. These NiAl compositions, which preferably contain a reactive element (such as zirconium and/or hafnium) and/or other alloying constituents (such as chromium), have been shown to improve the adhesion of a ceramic TBC, thereby increasing the spallation resistance of the TBC. These same compositions can also be used alone as environmental coatings for superalloy components that do not require the thermal protection of a TBC.
[0007] TBC systems and environmental coatings are being used in an increasing number of turbine applications (e.g., combustors, augmentors, turbine blades, turbine vanes, etc.). The material systems used for most turbine airfoil applications comprise a nickel-base superalloy as the substrate material, a diffusion platinum aluminide (PtAl) as the bond coat, and a zirconia-based ceramic as the thermally-insulating TBC material. Notable substrate materials include directionally-solidified (DS) alloys such as René 142 and single-crystal (SX) alloys such as René N5. A notable example of a PtAl bond coat composition is disclosed in U.S. Pat. No. 6,066,405 to Schaeffer. Finally, a preferred TBC material is yttria-stabilized zirconia (YSZ), with a suitable composition being about 3 to about 20 weight percent yttria. Improved spallation resistance can be achieved by depositing the TBC by electron-beam physical vapor deposition (EB-PVD) to have a columnar grain structure.
[0008] Approaches proposed for further improving the spallation resistance of TBC's are complicated in part by the compositions of the underlying superalloy and interdiffusion that occurs between the superalloy and the bond coat. For example, the above-noted bond coat materials contain relatively high amounts of aluminum relative to the superalloys they protect, while superalloys contain various elements that are not present or are present in relatively small amounts in these coatings. During bond coat deposition, a primary diffusion zone of chemical mixing occurs to some degree between the coating and the superalloy substrate as a result of the concentration gradients of the constituents. At elevated temperatures, further interdiffusion occurs as a result of solid-state diffusion across the substrate/coating interface. The migration of elements across this interface alters the chemical composition and microstructure of both the bond coat and the substrate in the vicinity of the interface, generally with deleterious results. For example, migration of aluminum out of the bond coat reduces its oxidation resistance, while the accumulation of aluminum in the substrate beneath the bond coat can result in the formation of topologically close-packed (TCP) phases that, if present at sufficiently high levels, can drastically reduce the load-carrying capability of the alloy.
[0009] Certain high strength superalloys contain significant amounts of refractory elements, such as rhenium, tungsten, tantalum, hafnium, molybdenum, niobium, and zirconium. If present in sufficient amounts or combinations, these elements can reduce the intrinsic oxidation resistance of a superalloy and, following deposition of a diffusion aluminide coating, promote the formation of a secondary reaction zone (SRZ) that contains deleterious TCP phases. A notable example of such a superalloy is commercially known as MX4, a fourth generation single-crystal superalloy disclosed in commonly-assigned U.S. Pat. No. 5,482,789. There has been an ongoing effort to develop coating systems that substantially reduce or eliminate the formation of SRZ in high-refractory alloys coated with diffusion aluminide and overlay coatings. For example, ruthenium-containing diffusion barrier layers are disclosed in commonly-assigned U.S. Pat. No. 6,306,524 to Spitsberg et al. and commonly-assigned and copending U.S. patent application Ser. Nos. 09/681,821, 09/683,700, and 10/605,860 to Zhao et al.
[0010] In addition to issues attributable to the superalloy composition, all TBC systems exhibit a temperature-thermal-cycle-time capability that limits the useful life of the TBC system. More particularly, all TBC coating systems are limited by the occurrence of oxide spallation, which results in the loss of a portion of TBC followed by thermal degradation of the bond coat and environmental and thermal degradation of the underlying substrate. Coating system performance has been determined to be dependent on a number of factors, including stresses arising from the growth of a thermally-grown oxide (TGO) that develops at the interface between the TBC and bond coat, stresses due to the thermal expansion mismatch between the ceramic TBC and the metallic bond coat, the fracture resistance of the TGO interface (affected by segregation of impurities, roughness, oxide type and others), and time-dependent and time-independent plastic deformation of the bond coat that leads to rumpling of the bond coat/TGO interface. Therefore, advancements in TBC coating system are concerned with delaying the first instance of oxide spallation, affected by the above factors.
SUMMARY OF INVENTION
[0011] The present invention provides an article and TBC coating system thereon that in combination exhibit significantly improved spallation resistance. Surprisingly, improved spallation resistance can be achieved with bond coats applied to certain substrate materials that are known to exhibit relatively poor intrinsic oxidation resistance as a result of their high refractory element content.
[0012] More particularly, the article comprises a substrate formed of a metal alloy containing ruthenium, i.e., more than 0.0 weight percent and above any amount that might be unintentionally present as an impurity, and optionally one or more refractory elements (e.g., tantalum, tungsten, molybdenum, and/or rhenium). The substrate is protected by a coating system comprising an aluminum-containing bond coat on the surface of the substrate and a ceramic coating bonded to the substrate by the bond coat. The bond coat is deposited so as to be substantially free of ruthenium, which is nonetheless present in the bond coat as a result of diffusion from the substrate into the bond coat in view of the absence of a diffusion barrier between the substrate and bond coat. As a result of the permitted diffusion mechanism, the bond coat initially has a higher ruthenium content adjacent the substrate than adjacent the ceramic coating.
[0013] A significant and unexpected advantage of this invention is that, though the superalloy substrate may have a high refractory element content, spallation resistance of the ceramic coating (TBC) on the substrate is somehow improved by the ruthenium content of the substrate. For example, the present invention has been demonstrated with diffusion PtAl bond coats and beta-phase NiAl overlay bond coats deposited on the MX4 alloy, whose tantalum, tungsten, molybdenum, and rhenium contents are similar to or slightly higher than other high-refractory superalloys, but which further contains about 0.4 to about 6.5 wt. % ruthenium. Notably, the spallation resistance exhibited with the MX4 superalloy was unexpected in view of its poor intrinsic oxidation resistance. Furthermore, the level of TBC spallation resistance exhibited with MX4 was not observed with other high-refractory superalloys that do not contain ruthenium.
[0014] Other objects and advantages of this invention will be better appreciated from the following detailed description.
BRIEF DESCRIPTION OF DRAWINGS
[0015] FIG. 1 is a perspective view of a high pressure turbine blade.
[0016] FIG. 2 is a cross-sectional representation of a TBC system on a surface region of the blade of FIG. 1 in accordance with an embodiment of this invention.
[0017] FIG. 3 is a chart evidencing differences in TBC spallation resistance between TBC systems deposited on a ruthenium-free superalloy and a ruthenium-containing superalloy.
[0018] FIG. 4 is a graph evidencing a difference in bond coat rumpling between PtAl diffusion bond coats deposited on a ruthenium-free superalloy and a ruthenium-containing superalloy.
DETAILED DESCRIPTION
[0019] The present invention is generally applicable to components that employ a thermal barrier coating (TBC) system for protection from their operating environment. Notable examples of such components include the high and low pressure turbine nozzles and blades, shrouds, combustor liners and augmentor hardware of gas turbine engines. An example of a high pressure turbine blade 10 is shown in FIG. 1 . The blade 10 generally includes an airfoil 12 against which hot combustion gases are directed during operation of the gas turbine engine, and whose surface is therefore subjected to severe attack by oxidation, corrosion and erosion. The airfoil 12 is anchored to a turbine disk (not shown) with a dovetail 14 formed on a root section 16 of the blade 10 . While the advantages of this invention will be described with reference to components of a gas turbine engine, such as the high pressure turbine blade 10 shown in FIG. 1 , the teachings of this invention are generally applicable to other components that benefit from a TBC system.
[0020] Represented in FIG. 2 is a surface region of the blade 10 that is protected by a TBC system 20 in accordance with an embodiment of the present invention. As shown, the TBC system 20 includes a bond coat 24 overlying a superalloy substrate 22 , which is typically the base material of the blade 10 . The bond coat 24 is shown as adhering a thermal-insulating ceramic layer 26 , or TBC, to the substrate 22 . As will be discussed in greater detail below, the bond coat 24 is an aluminum-containing composition, and consequently is depicted in FIG. 2 as having a thermally grown oxide (TGO) 28 , generally aluminum oxide (alumina), that promotes adhesion of the TBC 26 to the bond coat 24 . As shown, the TBC 26 has a strain-tolerant columnar grain structure obtained by depositing the TBC 26 using a physical vapor deposition (PVD) technique known in the art (e.g., EB-PVD), though a plasma spray technique could be used to deposit a noncolumnar ceramic layer. A preferred material for the TBC 26 is an yttria-stabilized zirconia (YSZ), a preferred composition being about 6 to about 8 weight percent yttria, optionally with up to about 20 weight percent of an oxide of a lanthanide-series element to reduce thermal conductivity. Other ceramic materials could be used for the TBC 26 , such as yttria, nonstabilized zirconia, or zirconia stabilized by magnesia, ceria, scandia, and/or other oxides. The TBC 26 is deposited to a thickness that is sufficient to provide the required thermal protection for the underlying substrate 22 and blade 10 , generally on the order of about 75 to about 300 micrometers.
[0021] A feature of the present invention is the ability to achieve greater spallation resistance for the TBC 26 through a combination of an aluminide bond coat 24 and a ruthenium-containing metal alloy substrate 22 . It is believed that the diffusion of ruthenium from such an alloy has a potent solid-solution strengthening effect on an aluminide coating when introduced into the coating by diffusion during high-temperature exposure or service. The result of this interdiffusion is an increase in the spallation resistance of the TBC 26 deposited on the aluminide bond coat 24 , apparently as a result of increased yield or creep strength of the bond coat 24 that reduces the amount of bond coat rumpling that occurs.
[0022] Reduced levels of rumpling and greater TBC spallation lives have been demonstrated for TBC deposited on PtAl diffusion aluminide and beta-phase NiAl overlay bond coats applied to substrates formed of the high-refractory nickel-based superalloy commercially known as MX4, which has a minimum ruthenium content of about 0.4 weight percent. It is believed that other suitable materials for use in this invention include other alloys that contain an appreciable amount of ruthenium, i.e., above any amount that might be unintentionally present as an impurity. On the basis of results obtained with the MX4 alloy, the benefits of the present invention are believed to be especially evident for single-crystal nickel-based superalloys that contain at least 0.4 weight percent ruthenium and at least one additional refractory metal, e.g., about 6.5 weight percent or more of tantalum, about 5 weight percent or more of tungsten, about 2 weight percent or more of molybdenum, about 3 weight percent or more of rhenium, about 0.1 weight percent or more of hafnium, etc. As disclosed in U.S. Pat. No. 5,482,789, the MX4 superalloy may contain, by weight, about 0.4% to about 6.5% ruthenium, about 5.8% to about 10.7% tantalum, about 3.0% to about 7.5% tungsten, about 0.9% to about 2.0% molybdenum, about 4.5% to about 5.75% rhenium, up to about 0.15% hafnium, about 4.25% to about 17.0% cobalt, about 1.25% to about 6.0% chromium, about 5.0% to about 6.6% aluminum, up to about 0.06% carbon, up to about 0.01% boron, up to about 0.02% yttrium, up to about 1.0% niobium, up to about 1.0% titanium, a molybdenum+chromium+niobium content of about 2.15% to about 9.0%, an aluminum+titanium+tungsten of about 8.0% to about 15.1%, and the balance nickel and incidental impurities. Other notable examples of high-refractory superalloys that may include ruthenium as an optional constituent are single-crystal superalloys commercially known under the names René 162 (U.S. Pat. No. 5,151,249) and René N6 (U.S. Pat. Nos. 5,270,123 and 5,455,120). However, commercially used compositions of these alloys do not contain ruthenium, and therefore the benefits attributed by this invention to the diffusion of ruthenium into an aluminide coating on these alloys were not previously obtained.
[0023] As noted above, the bond coat 24 employed by this invention is preferably a diffusion aluminide or beta-phase NiAl intermetallic overlay coating. A preferred diffusion aluminide bond coat is a platinum aluminide (containing nickel aluminide and platinum aluminide intermetallics) disclosed in U.S. Pat. No. 6,066,405 to Schaeffer, and can be deposited by such known aluminizing processes as pack cementation, vapor phase deposition (VPA), and chemical vapor deposition (CVD) techniques. Suitable beta-phase NiAl intermetallic overlay coatings are disclosed in U.S. Pat. Nos. 6,153,313, 6,255,001, and 6,291,084, with preferred coatings containing, in atomic percent, about 30% to about 60% aluminum, optionally up to about 10% chromium, about 0.1% to about 1.2% of a reactive element such as zirconium and/or hafnium, optional additions of silicon and/or titanium, the balance essentially nickel. A beta-phase NiAl overlay bond coat 24 can be deposited by various physical vapor deposition processes, including EB-PVD, cathodic arc physical vapor deposition, ion plasma deposition (IPD), and thermal spray.
[0024] FIG. 2 represents a diffusion zone 30 as being present beneath the bond coat 24 . The depth and composition of the diffusion zone 30 will depend on the coating type, deposition technique used to deposit the bond coat 24 , and thermal history of the blade 10 . The diffusion zone 30 contains various intermetallic and metastable phases that form as a result of diffusional gradients and changes in elemental solubility in the local region of the substrate 22 . Over time at elevated temperatures, the diffusion zone 30 grows and, if the refractory content of the substrate 22 is sufficiently high (e.g., MX4, René 162 and N6), form the aforementioned SRZ containing detrimental TCP phases. Because these deleterious phases reduce rupture strength, ductility and fatigue resistance of the substrate alloy, previous efforts have been directed to developing diffusion barriers between high-refractory superalloy substrates (e.g., MX4, René 162 and N6) and aluminum-containing coatings, such as the substrate 22 and aluminide bond coat 24 depicted in FIG. 2 .
[0025] In an investigation leading to the present invention, substantially identical commercial PtAl diffusion coatings were applied to one-inch (about 25 mm) diameter button coupons of two different single-crystal substrate materials: René N5 and the MX4. The N5 alloy (U.S. Pat. No. 6,074,602) is a ruthenium-free alloy having a nominal composition of, by weight, about 7.5% Co, 7.0% Cr, 6.5% Ta, 6.2% Al, 5.0% W, 3.0% Re, 1.5% Mo, 0.15% Hf, 0.05% C, 0.004% B, 0.01% Y, the balance nickel and incidental impurities. The PtAl coatings were nominally 0.0020 to 0.0025 inch (about 0.051 to 0.064 mm) in thickness. A 5 mil (about 125 micrometer) topcoat of zirconia stabilized by about 7 weight percent yttria (7% YSZ) was deposited by EB-PVD as a TBC on the PtAl coatings. These samples underwent a furnace cycle test (FCT) in which the temperature was cycled between about 400° F. (about 200° C.) and about 2125° F. (about 1160° C.), with an approximate 45-minute hold at the elevated temperature and 15 minutes for cooling to the lower temperature. Cycling continued for each button until about 20% of the TBC had spalled from the button.
[0026] FIG. 3 is a chart showing that the MX4/PtAl specimens had an average FCT life of about 416 cycles, or about 1.75 times the 236-cycle life exhibited by the N5/PtAl specimens. An analysis of variance demonstrated that the two sample populations were different to greater than 95% confidence level. FIG. 4 is a graph that plots the amount of surface roughness, or rumpling, that ocurred in specimens taken from each of the two specimen groups. From FIG. 4 , it can be seen that the PtAl/MX4 specimen incurred much less bond coat deformation than the PtAl/N5 specimen, which suggested that a beneficial strengthening effect occurred when a PtAl bond coat was deposited on an MX4 substrate.
[0027] In a second investigation, beta-phase NiAlCrZr overlay bond coats were applied by EB-PVD to additional N5 and MX-4 button specimens, which were then coated with 7% YSZ TBC such that, aside from the bond coats, the specimens were essentially identical to the specimens of the first investigation. The NiAl coatings were nominally about 0.0016 to 0.0020 (about 0.041 to about 0.051 mm) in thickness. All specimens underwent the same 2125° F. FCT test conducted in the first investigation. The results of this investigation are also represented in FIG. 3 , which shows that the MX4/NiAl specimens had an average FCT life of about 1015 cycles, which was more than twice the 423-cycle life exhibited by the N5/NiAl specimens. An analysis of variance performed on the data demonstrated that the two sample populations were different to greater than 95% confidence level. Notably, this test also demonstrated the superiority of the NiAlCrZr bond coats over the PtAl diffusion bond coats in terms of TBC spallation resistance.
[0028] In a third investigation, beta-phase NiAlCrZr overlay bond coats were applied by EB-PVD to René N6 button specimens. The N6 alloy has a nominal composition, by weight, about 12.5% Co, 4.2% Cr, 7.2% Ta, 5.75% Al, 5.75% W, 5.4% Re, 1.4% Mo, 0.15% Hf, 0.05% C, 0.004% B, 0.01% Y, the balance nickel. The specimens were coated with 7% YSZ TBC such that, aside from the substrate material, the specimens were essentially identical to the specimens of the first and second investigations. These specimens then underwent the same 2125° F. FCT test carried out in the first and second investigations. The results of this test were that the N6/NiAlCrZr specimens had an average FCT life of about 479 cycles, which was only about 10% higher than the N5/NiAlCrZr specimens of the second investigation. An analysis of variance performed on the data demonstrated that the sample populations from the N6/NiAlCrZr specimens of this investigation and the MX4/NiAlCrZr specimens of the second investigation were different to greater than 95% confidence level. Accordingly, while the N6/NiAlCrZr specimens exhibited some improvement (about 10% higher) in FCT life over the N5/NiAlCrZr specimens, the MX4/NiAlCrZr specimens unexpectedly exhibited a far more pronounced improvement in FCT life (about 140% higher).
[0029] In that the MX4 and N6 alloys both contain relatively high levels of tantalum, tungsten, molybdenum, and rhenium, but differ by the presence of ruthenium in the MX4 alloy, it was theorized that the ruthenium content of MX4 was primarily responsible for the drastic improvement in the FCT lives of the TBC deposited on their aluminide bond coats. Such results were obtained even though MX4 is known to exhibit poorer intrinsic oxidation resistance than N6. However it was theorized that, during FCT cycling, sufficient ruthenium had diffused into the aluminide bond coats from the MX4 substrates, resulting in a ruthenium concentration gradient through the bond coats (higher adjacent the substrates) that had a beneficial effect on the spallation lives of the TBC″s deposited on the bond coats.
[0030] While the invention has been described in terms of particular embodiments, it is apparent that other forms could be adopted by one skilled in the art. Therefore, the scope of the invention is to be limited only by the following claims. | An article and TBC coating system thereon that in combination exhibit significantly improved spallation resistance. The article comprises a substrate formed of a metal alloy containing ruthenium and one or more refractory elements (e.g., tantalum, tungsten, molybdenum, rhenium, hafnium, etc.). The substrate is protected by a coating system comprising an aluminum-containing bond coat on the surface of the substrate and a ceramic coating bonded to the substrate by the bond coat. The bond coat, preferably an aluminide, is deposited so as to be substantially free of ruthenium, though ruthenium is present in the bond coat as a result of diffusion from the substrate into the bond coat. | 8 |
BACKGROUND OF THE INVENTION
The Wacker-type oxidation of ethylene to acetaldehyde using a palladium chloride/cupric chloride/hydrochloric acid catalyst in an aqueous solution has been modified and applied to the synthesis of methyl ketones from terminal olefins. However, major problems have been encountered in using the Wacker-type oxidation in the oxidation of higher olefins and internal olefins. One problem is that of reduced rates of reaction due to the low solubility of the olefin in the aqueous medium. Another major problem is the concomitant secondary oxidation of the ketone product which leads to poor selectivities and poor yield of desired product.
The solubility problems encountered in the Wacker-type oxidation of higher olefins have been at least partially solved by resorting to "phase transfer" techniques and the addition of a suitable surfactant. Thus, the prior art teaches that the reaction of the olefinic hydrocarbon reactant to be oxidized in the presence of free oxygen is preferably carried out in a multi-phase diluent system, preferably a two-phase system with one phase aqueous and the other organic. The catalysts known for this multi-phase process are Pd/Cu/alkali metal or alkaline earth metal chloride catalyst or Pd/Cu/boric acid catalyst with the palladium being either free palladium or a palladium compound and the copper component being either a cuprous or a cupric compound. It should also be noted that the HCl used in conventional Wacker oxidation reactions to maintain adequate conversion levels of the olefinic reactant has been eliminated as a component of the multi-phase process. An additional component of this multi-phase prior art reaction system is a suitable surfactant.
Corrosion of metallic process equipment is an additional problem when a catalyst containing halide ions such as the conventional Wacker or modified Wacker-type catalysts are utilized in the oxidation process, and a low-corrosion catalyst can be desirable at times.
THE INVENTION
In accordance with the present invention, an oxidation process described wherein a catalyst with greatly reduced halide content is utilized in a multi-phase diluent system in presence of a boric acid component and with the optional additional of a suitable surfactant. In one embodiment of the invention, a catalyst system containing PdCl 2 , a heteropolyacid H 9 [PMo 6 V 6 O 40 ], H 3 BO 3 , water and decane as a two-phase diluent system, and cetyltrimethylammonium bromide as an optical phase transfer catalyst, show good results in the oxidation of 2-butene to methyl ethyl ketone.
ADVANTAGES
The catalyst system of the invention is an inexpensive alternative to the use of phase transfer agents in the two-phase oxidation of olefins with PdCl 2 and heteropolyacids.
In addition to improvments in selectivity to ketone products, use of the catalysts of the invention means that reactor cleanup is minimal because no scum or deposits are formed when boric acid is used.
Furthermore, the palladium/heteropolyacid/boric acid system is amenable to recycle while improving catalyst handling.
OBJECTS OF THE INVENTION
It is one object of the invention to produce a catalyst useful for the oxidation of olefins to ketones.
It is another object of the invention to produce a process whereby ketones can be efficiently produced via the oxidation of olefins.
DESCRIPTION OF THE INVENTION
I. Catalyst System
The catalyst utilized according to the instant invention for the oxidation of olefinic hydrocarbons to carbonyl compounds is made up of three components: (1) a palladium component, (2) a heteropolyacid component, and (3) boric acid component. The use of another component, (4) a surfactant, is optional.
(1) Palladium Component
The palladium component of the catalyst system of the instant invention can be any palladium-containing material whose properties render it suitable for use in Wacker or Wacker-type reactions. The palladium component of the invention can be palladium metal, e.g., finely divided palladium powder, or a palladium compound. Examples of suitable palladium compounds include allyl palladium chloride dimer [C 3 H 5 PdCl] 2 , dichlorobis(triphenylphosphine)palladium(II), palladium (II) acetate, palladium(II) acetylacetonate, tetrakis(triphenylphosphine)palladium(O), palladium(II) chloride, palladium(II) iodide, palladium(II) nitrate, palladium(II) sulfate, and the like. Mixtures of the above palladium compounds can also be utilized as the palladium component of the instant catalyst system if so desired, thus providing a means to minimize the halide content of the catalyst system.
(2) Heteropolyacid Component
The heteropolyacid component of the catalyst system of the instant invention should have a redox potential in excess of 0.5 volt and contain at least two metallic species. It is preferred that it contain molybdenum and vanadium. Such preferred heteropolyacids are defined herein as iso-polymolybdates in which one or more of the molybdenum atoms are replaced by vanadium or an iso-polyvanadate in which one or more of the vanadium atoms are replaced by molybdenum.
The polyacid used contains vanadium atoms, for example from 1 to 8, more preferably 6 atoms, in a molecule, and molybdenum. Typical polyacids for use in the present invention are represented by the following general formula:
H.sub.m [X.sub.x Mo.sub.a V.sub.b M.sub.y O.sub.z ]
in which
X is B, Si, Ge, P, As, Se, Te or I;
M is W, Nb, Ta or Re;
m, a, b and z are integers;
x is zero (for mixed isopolyacids) or an integer (for hetero-polyacids);
and y is zero or an integer such that ##EQU1##
and m+Nx+6a+5b+N'y≦2z
in which each of N and N' is the number of the group of the periodic table to which X and M respectively belong. Examples of typical heteropolyacids are as follows:
______________________________________Heteropolyacid Redox potential, V______________________________________H.sub.9 [TeMo.sub.3 V.sub.3 O.sub.24 ] +0.80H.sub.4 [As.sub.2 Mo.sub.12 V.sub.6 O.sub.61 ] +0.65H.sub.3 [AsMo.sub.6 V.sub.6 O.sub.40 ] +0.72H.sub.6 [SiMo.sub.10 V.sub.2 O.sub.40 ]H.sub.6 [GeMo.sub.10 V.sub.2 O.sub.40 ]H.sub.n [PMo.sub.p V.sub.q O.sub.40 ]*, for example:H.sub.4 [PMo.sub.11 VO.sub.40 ] +0.65H.sub.5 [PMo.sub.10 V.sub.2 O.sub.40 ] +0.70H.sub.6 [PMo.sub.9 V.sub.3 O.sub.40 ] +0.72H.sub.7 [PMo.sub.8 V.sub.4 O.sub.40 ] +0.75H.sub.8 [PMo.sub.7 V.sub.5 O.sub.40 ] +0.76H.sub.9 [PMo.sub.6 V.sub.6 O.sub.40 ] +0.77H.sub.10 [PMo.sub.5 V.sub.7 O.sub.40 ] +0.79H.sub.11 [PMo.sub.4 V.sub.8 O.sub.40 ] +0.80H.sub.5 [Mo.sub.r W.sub.m V.sub.2 O.sub.40 ]**H.sub.9 [PMo.sub.3 W.sub.3 V.sub.6 O.sub.40 ] +0.70______________________________________ *in which n = 3 + q, p = 12 - q, q = 1 to 10 **in which m = 2, 4, 6, or 8 and r = 10 - m.
The ratios of the various catalyst components can be expressed in terms of a molar ratio of heteropolyacid to palladium. The molar ratio of heteropolyacid component to palladium component in the instant catalyst system is broadly from 1/1 to 50/1.
The amount of catalyst employed according to the instant invention can be expressed in terms of the molar ratio of olefinic hydrocarbon reactant to palladium component of the catalyst system. Broadly, the molar ratio of olefinic reactant to palladium component is from about 5/1 up to 1000/1 and preferably from about 10/1 up to 250/1.
(3) Boric Acid Component
The boric acid component of the catalyst system of this invention can be any boron-containing material that provides a catalytically active boric acid under the conditions of the oxidation reaction of this invention. Suitable boron-containing materials include boric acids, boron oxides, and boric acid esters. Specific examples of suitable boron components include orthoboric acid (H 3 BO 3 ), metaboric acid (HBO 2 ), tetraboric acid, (H 2 B 4 O 7 ), boron oxide (B 2 O 3 ), triethyl borate, tributyl borate, and triphenyl borate. Orthoboric acid (H 3 BO 3 ), is the currently preferred boric acid component of this invention.
The amount of boric acid used in the oxidation reaction of this invention can be varied widely. Generally, any amount which assures effective interaction with the other catalyst components and produces the results disclosed herein can be employed. Typically, the molar ratio of boric acid or precursor thereof to palladium component will be from about 0.2/1 up to about 100/1 and preferably from about 5/1 up to about 25/1.
(4) Surfactant Component
Generally, the surfactant component of the reaction system according to the instant invention comprises one or more compounds which exhibit surface-active properties--i.e., surfactants. However, the term "surfactant" encompasses a very broad class of compounds, and it has been discovered that not all surfactants are suitable for use in the instant invention. Nevertheless, for convenience and simplicity, the suitable compounds that can be employed according to the instant invention and described more fully below will be termed surfactants herein. At the present time, it is not known whether, in the catalyst and process of the invention, these compounds functions as phase-transfer catalysts, such as is taught in the art, or whether they function as micellar catalysts, a feature also disclosed in the prior art. Because of this uncertainty in the mode of action of these compounds in the instant invention, and for convenience, the following compounds will merely be described herein as surfactants.
A preferred surfactant for use in the reaction system of the instant invention is selected from one of the five following groups: (A) Quaternary ammonium salts of the general formula (R"') 4 N + X - wherein R"' is an alkyl radical of from 1 to 20 carbon atoms and wherein the total number of carbon atoms in said quaternary ammonium salt is from 8 to 30 carbon atoms broadly and preferably from 16 to 22 carbon atoms; and wherein X is selected from the group consisting of Br - , Cl - , I - , F - , R"', CO 2 - , QSO 3 - , BF 4 - , and HSO 4 - , wherein Q is an aryl, alkaryl or arylalkyl radical of 6 to 10 carbon atoms. It will be noted that a variety of anions are suitable as the X - component of the quaternary ammonium salts.
Useful quaternary ammonium salts according to the general formula given above include cetyltrimethylammonium bromide,
hexadecyltrimethylammonium bromide,
tetraheptylammonium bromide, cetyltrimethylammonium stearate,
benzyltributylammonium chloride, benzyltriethylammonium bromide,
benzyltrimethylammonium bromide, phenyltrimethylammonium bromide,
phenyltrimethylammonium iodide, tetrabutylammonium bromide,
tetrabutylammonium chloride, tetrabutylammonium hydrogen sulfate, tetrabutylammonium iodide, tetraethylammonium bromide, tetrabutyl ammonium fluoride, and tetrabutylammonium tetrafluoroborate.
(B) Akali metal alkyl sulfates of the general formula R' v OSO 3 M, wherein R' v is an alkyl radical having from 10 to about 20 carbon atoms and wherein M is an alkali metal. Examples of suitable compounds according to the general formula for the alkali metal alkyl sulfates include lithium decylsulfate, potassium dodecylsulfate, sodium dodecylsulfate, sodium hexadecylsulfate, potassium hexadecylsulfate, rubidium dodecylsulfate, cesium dodecylsulfate, sodium octadecylsulfate, potassium octadecylsulfate, potassium eicosylsulfate, sodium eicosylsulfate and the like.
(C) Akali metal salts of alkanoic acids of the general formula R' v CO 2 M, wherein R' v and M have the same meaning as given above for the compounds of (B). Examples of suitable alkali metal salts of alkanoic acids include lithium deconoate, sodium dodecanoate, potassium dodecanoate, rubidium dodecanoate, cesium dodecanoate, sodium hexadecanoate, potassium hexadecanoate, sodium octadecanoate, potassium octadecanoate, sodium eicosanoate, potassium eicosanoate, and the like.
(D) Alkali metal salts of alkaryl sulfonic acids of the general formula ##STR1## wherein R' v and M have the same meaning as given and wherein R v is an alkyl radical of 1 to 4 carbon atoms and wherein n is 0 or an integer of from 1 to 4. Typical compounds within the (D) group include sodium dodecylbenzenesulfonate, potassium dodecylbenzenesulfonate, lithium dodecylbenzenesulfonate, sodium tetradecylbenzenesulfonate, potassium hexadecylbenzenesulfonate, rubidium dodecylbenzenesulfonate, cesium dodecylbenzenesulfonate, sodium octadecylbenzenesulfonate, potassium octadecylbenzenesulfonate, sodium eicosylbenzenesulfonate, potassium dodecyltoluenesulfonate, sodium dodecylxylenesulfonate and the like.
(E) 1-Alkyl pyridinium salts of the general formula ##STR2## wherein R' v and X - have the same meanings as described above. Examples of suitable 1-alkyl pyridinium salts are 1-dodecylpyridinium para-toluenesulfonate, 1-dodecylpyridinium chloride, 1-hexadecylpyridinium chloride, 1-hexadecylpyridinium para-toluenesulfonate, 1-decylpyridinium chloride, 1-hexadecylpyridinium bromide, 1-tetradecylpyridinium chloride, 1-octadecylpyridinium chloride, 1-eicosylpyridinium chloride, 1-octadecylpyridinium benzenesulfonate, and the like.
The amount of surfactant compound selected from groups (A) through (E) which is utilized according to the instant invention can be expressed in terms of a mole ratio based on the pallidium component of the catalyst system. Broadly, the mole ratio of surfactant to palladium compound will be from 0.01/1 to 10/1. Preferably, it will be from 0.1/1 to 3/1.
II. Diluent System
As indicated above, the oxidation of the olefinic hydrocarbon according to the instant invention is carried out in the presence of a diluent comprised of at least two liquid pahses, preferably only two, at least one of which is an aqueous phase.
The nonaqueous phase will hereinafter be termed the organic phase. Said organic phase should be relatively inert to the oxidation conditions, of course, and also relatively inert to hydrolysis-type reactions. Furthermore, it is apparent that if at least two phases are present, at least one of which is an aqueous phase, that the organic diluent utilized must have somewhat limited solubility in the aqueous phase. In addition, the choice of the organic diluent(s) may be often determined based on the difference in boiling points expected between the product of the oxidation reaction and the organic diluent so as to facilitate separation of the components of the reaction mixture. Within these general requirements, a rather broad range of organic compounds can be utilized to form the organic phase according to the instant invention.
Generally speaking, suitable compounds can be found in the classes of compounds described as aliphatic hydrocarbons, aromatic hydrocarbons or alkylsubstituted aromatic hydrocarbons, halogenated aromatic compounds, and esters of aromatic carboxylic acids although the latter may be less preferred because of a tendency toward hydrolysis of the ester group in certain instances. In addition, it has been found that compounds such as nitrobenzene and benzonitrile, commonly utilized as solvents for many organic reactions, show a definite inhibitory effect on the reaction of the instant invention presumably by complexing of one or more catalyst components.
Suitable organic diluents include cyclohexane, hexane, octane, decane, dodecane, tetradecane, hexadecane, benzene, toluene, chlorobenzene, methylbenzoate, bromobenzene, 1,2,4-trichlorobenzene, ortho-dichlorobenzene, ortho-xylene, para-xylene, meta-xylene, methylcyclopentane, dimethyl ortho-phthalate, and the like. Mixtures of organic diluents may be utilized in some cases desired.
The amounts of the aqueous phase and organic diluent phase based on the starting olefinic reactant can vary over a wide range, and a suitable range includes from about 20 to 0.2 volumes of organic diluent per volume of olefinic hydrocarbon reactant, preferably from about 5 to 1 volumes of organic diluent per volume of olefinic hydrocarbon reactant. Similarly, the broad range for the amount of aqueous phase is from 20 to 0.2 volumes per volume of olefinic hydrocarbon reactant and preferably from 5 to 1 volumes per volume of olefinic hydrocarbon reactant.
It is worth pointing out some predictions relating to the expected effects of the volume of aqueous phase on the oxidation reaction of the instant invention. First, if the aqueous phase volume becomes too small, the concentration of the catalyst components in the aqueous phase can cause a decrease in the solubility of the olefinic hydrocarbon reactant in the aqueous phase, thus greatly slowing down the reaction rate wherein the olefinic hydrocarbon reactant is oxidized to the desired carbonyl compound. Secondly, if the aqueous phase becomes too large, the concentration of catalyst components can be so dilute that the reaction with the olefinic hydrocarbon can also be greatly slowed. However, it can be seen that a judicious choice of the optimum amount of the aqueous phase for high conversion levels of the olefinic hydrocarbon reactant can readily be determined by a few well-chosen experiments.
At present, it is believed that the primary function of the organic phase in the reaction system of the instant invention is to greatly increase the selectivity to the desired carbonyl compound by effectively removing the carbonyl compound product from the locus of the oxidation reaction thereby preventing side reactions such as isomerization and/or further oxidation of the carbonyl compound. However, this explanation is to be treated merely as one possible theory of the mode of action of the organic phase in the reaction and applicants should not be bound to same.
III. Oxygen
As indicated previously, the reaction of the instant invention is an oxidation reaction whereby an olefinic reactant is converted to a carbonyl compound in the presence of a catalyst and diluent system described above. Thus, the reaction of the instant invention is carried out in the presence of free oxygen. The oxygen may be supplied to the reaction mixture essentially as pure oxygen or in admixture with other gases which are essentially inert to the reaction conditions. Air can be utilized as a source of oxygen for the oxidation reaction of this invention.
As is generally true for most oxidation reactions, the reaction of the instant invention can be exothermic and thus some care should be exercised in controlling the amount of oxygen present in the reaction system. For this reason, and also to improve control of the temperature of the reaction, it is preferred to add oxygen or the gaseous mixture containing oxygen to the reaction zone incrementally so that explosive oxygen concentrations do not develop. The pressure of oxygen utilized for the instant invention can be from about 2 up to 250 psig and, preferably, from about 10 to 100 psig above the autogenous pressure at the temperature utilized.
IV. Olefinic Hydrocarbon Reactant
The olefinic hydrocarbon reactant which is oxidized according to the process of the instant invention can be selected from the groups consisting of acyclic olefinic compounds containing from 2-20 carbon atoms per molecule and having 1, 2, or 3 olefinic carbon-carbon double bonds per molecule and cyclic olefinic compounds containing from 5-20 carbon atoms per molecule and having 1, 2, or 3 olefinic carbon-carbon double bonds per molecule. Within the limitations described above, suitable olefinic hydrocarbon reactants can be represented by the general formula RCH═CHR' wherein R and R' are selected from the group consisting of hydrogen, alkyl, alkenyl, alkadienyl, cycloalkyl, cycloalkenyl, and cycloalkadienyl radicals and wherein R can be the same or different from R' and wherein R and R' taken together can form an alkylene or alkenylene or alkadienylene radical thus forming a cyclic system. The term "olefinic carbon-carbon double bond" as used herein is not meant to include those carbon-carbon double bonds which are part of an aromatic carbocyclic system of alternating single and double bonds.
Examples of suitable monoolefinic compounds are ethylene, propylene, 1-butene, 2-butene, 1-pentene, 2-pentene, 1-hexene, 2-hexene, 1-octene, 1-decene, 1-dodecene, 1-hexadecene, 1-octadecene, 1-eicosene, vinyl cyclohexane, cyclopentene, cyclohexene, cycloheptene, cyclooctene, cyclododecene, 3,3-dimethyl-1-butene, and the like.
Examples of suitable diolefinic compounds are 1,3-butadiene, 1,3-pentadiene, 1,5-hexadiene, 4-vinylcyclohexene, 1,5-cyclooctadiene, 1,9-decadiene, 1,7-octadiene, 1,3-cycloheptadiene, and the like.
Suitable triolefinic compounds include 1,5,9-cyclododecatriene, cycloheptatriene, 1,6-diphenyl-1,3,5-hexatriene, and the like.
While the double bond unsaturation can be internal or non-terminal, it is preferred that at least one olefinic carbon-carbon double bond be in the terminal position. That is, the preferred olefinic reactant has at least one terminal olefinic or vinyl group. Mixtures of olefinic reactants can be employed.
V. Reaction Conditions
The particular temperature employed may be dependent somewhat on the olefinic hydrocarbon reactant. For example, at relatively high temperatures, a lower molecular weight olefinic hydrocarbon reactant may tend to be very insoluble in the aqueous phase of the two-phase system of the instant invention, thus causing a reduced conversion of the olefinic hydrocarbon reactant. On the other hand, a higher molecular weight olefinic reactant may be able to tolerate a higher reaction temperature and still maintain a reasonable degree of solubility in the aqueous phase and thus achieve a good degree of conversion at the higher temperature. The temperature utilized in the instant invention is broadly from about 20° to 200° C. and preferably from about 60° to 150° C. Most preferably it lies between about 70° and 100° C.
The time employed for the reaction according to the instant invention can vary over a wide range and will, to some extent, depend on the desired degreee of conversion of the olefinic hydrocarbon reactant. Generally, a time period such as from 30 minutes to 8 hours will be employed in the instant invention, preferably 1 to 3 hours.
Because the oxidation reaction according to the instant invention is carried out in the presence of a diluent system comprising at least two liquid phases, it is expected that good stirring will be beneficial. Conventional means of achieving good agitation and contact between the liquid phases can be employed.
The charge order of the reaction components and catalyst components is not critical in the process of the instant invention. However, the presence of oxygen in the reaction mixture prior to heating of the mixture to the desired reaction temperature appears to promote higher selectivity to the desired carbonyl compound.
The process of the instant invention can be carried out in either a batch or continuous process.
Reaction vessels and conduits utilized in the process of the instant invention should, of course, be able to withstand the oxidizing conditions which are present. For this reason, glass-lined, tantalum, titanium or Hastelloy C-clad vessels and conduits are recommended for use in the process of this invention.
VI. Reaction Mixture Workup
A variety of methods can be utilized to recover the products, unreacted olefinic hydrocarbon starting materials, and the catalyst in the aqueous phase in the instant invention. For example, the entire reaction mixture can be subjected to a fractional distillation to separate the components into various fractions or portions. The bottoms from said distillation can be recycled to the reaction zone as that portion contains essentially all of the catalyst system for the reaction.
Another method of treating the reaction mixture is to contact the entire mixture with a lower alkane such as n-pentane, then separate the aqueous phase from the organic phase, with subsequent fractional distillation of the organic phase to recover the products and any unreacted olefinic hydrocarbon reactants. The aqueous phase can be recycled to the reaction zone as described above, since it contains essentially all of the catalyst components.
Another method of reaction mixture workup involves admixture of the reaction mixture with a saturated aqueous sodium chloride solution followed by extraction of the mixture into diethyl ether. The ether extract can then be distilled or treated in such a manner as to remove the ether leaving the organic residue containing the product and any unreacted olefinic hydrocarbon reactant. Said residue can then be subjected to fractional distillation procedures to recover the various components.
VII. Product Utility
As indicated earlier, the reaction of the instant invention provides a process for the conversion of olefinic hydrocarbon reactants to carbonyl compounds. Said carbonyl compounds are ketones, except for the case of ethylene oxidation which yields acetaldehyde. If the olefinic hydrocarbon reactant contains two carbon-carbon double bonds, the product can be an unsaturated monoketone or diketone. Furthermore, the unsaturated monoketone can be recycled to the reaction zone for conversion to the diketone. Similarly a triolefinic reactant can be converted to intermediates such as unsaturated mono- or diketones and ultimately to a triketone. Ketones from the olefinic hydrocarbon reactants described in part IV above have generally well-known utilities. For example, they can be utilized as solvents (methyl ethyl ketone) or as intermediates in the synthesis of other chemical compounds (pinacolone).
VIII. Examples
In all of the runs that are described in the following examples, the reaction vessels utilized were a 300 cc Hastelloy C magnedrive stirred tank reactor sold by Autoclave Engineers or a 500 mL Fischer-Porter compatability aerosol bottle. The autoclave was heated by an electric heater and controlled by a Thermoelectric 400 temperature controller. The Fisher-Porter bottles were fitted with pressure gauges, vent and chargelines through which oxygen could be added continuously or incrementally. The oxygen line to the reaction vessel was fitted with the appropriate check valves and flame arrestor. The bottle was heated in an ethylene glycol bath, and monitored on an Acromag by a thermocouple placed in the glycol bath. The bottle contents were stirred by a magnetic stirrer.
For autoclave runs, the reactor was charged with the catalyst system, the diluents, and then sealed. Thirty psig oxygen pressure was introduced to pressure test the reactor, then vented. The olefinic reactant was then charged, while autoclave stirring was begun to aid olefin dissolution in the organic diluent. Thirty psig oxygen pressure was again introduced and the autoclave heated to the desired reaction temperature before the oxygen pressure was adjusted to the desired operating pressure. The reaction was allowed to take-up oxygen on demand for the duration of the reaction in order to maintain the desired pressure. For runs carried out in the Fischer-Porter bottles, the catalyst, diluents, and olefinic reactant were charged. The bottle was assembled with the proper fittings, placed in the ethylene glycol bath, and stirring begun. An initial pressure of 30 psig oxygen was introduced, the reaction mixture heated to the desired reaction value. As above, the system is allowed to take-up oxygen on demand to maintain the desired operating pressure throughout the reaction.
After the desired reaction time had elapsed the reaction was cooled to room temperature before excess oxygen was vented. The combined organic and aqueous phases were subjected to conventional fractional distillation to recover volatile materials (starting material, products and by-products). After distillation, the residual materials were phase separated, decane solvent was recycled to the reactor while the aqueous phase was evaporated to dryness, the residue redissolved in deionized water, H 2 SO 4 added to adjust pH to 1.9 and the resulting solution was then recycled to the reactor. All samples were analyzed by gas-liquid phase chromatography.
EXAMPLE I
Preparation of the Phospho-6-molybdo-6-vanadic acid
45.5 g Na 3 PO 4 .12H 2 O (0.12 mol), 103.6 g MoO 3 (0.72 mol), 42.0 g V 2 O 5 (0.23 mol) and 22.4 Na 2 CO 3 .10H 2 O (0.09 mol) were dissolved in 600 mL H 2 O. The solution was heated to boiling and stirred vigorously for 40 minutes. The solution gradually turned an intense brownish-red. The solution volume was reduced to 150 mL by evaporation, then allowed to cool to room temperature. The pH of the solution was adjusted to 1.00 with concentrated sulfuric acid, the solution was then filtered and set aside for use as a component in the inventive oxidation process.
EXAMPLE II
Two control runs were carried out in which 2-butene was oxidized to methyl ethyl ketone (MEK) in the absence of organic diluent and surfactant component. The same heteropolyacid charge was used in each run, with boric acid added to the second run. Both runs were carried out in 300 cc Hastelloy C autoclaves following the general procedure set forth above. One hundred mL of water and reagents in the amounts specified in Table I were treated for 2 hours at 80° C. and 100 psig.
TABLE I__________________________________________________________________________ Butene Butene Selectivity Heteropolyacid, H.sub.3 BO.sub.3, Charged, Conversion, to MEK,Run# PdCl.sub.2, mol mol mol mol mol % mol %__________________________________________________________________________1 .01 .05 -- 0.48 17.7 77.52 .01 .05 0.25 0.45 10.0 98.4__________________________________________________________________________
The results of these experiments demonstrate the poor performance of the palladium/heteropolyacid catalyst system at 80° and 100 psig when carried out in aqueous phase only, with or without added boric acid.
EXAMPLE III
A control run was carried out in which 2-butene was oxidized to MEK utilizing the palladium chloride-heteropolyacid catalyst system in a two-phase medium in the absence of boric acid or a surfactant component. The reaction was carried out in a 500 mL Fischer-Porter bottle according to the general procedure set forth above. One hundred mL water and 100 g (137 mL) decane containing 0.01 mol PdCl 2 , 0.05 mol heteropolyacid, 0.46 mol 2-butene were reacted for 2 hours at 80° C. and 100 psig. Analysis of the final product revealed a 2-butene conversion of only 2.9% with a selectivity to MEK of 99.6%.
The results of this experiment demonstrate the poor performance of the palladium/heteropolyacid catalyst system in two-phase medium in the absence of surfactant or boric acid component.
EXAMPLE IV
A control run was carried out in which 1-butene was oxidized to methyl ethyl keton utilizing the palladium chloride-heteropolyacid catalyst system in a two-phase medium in the absence of boric acid or a surfactant component. The reaction was carried out in a 500 mL Fischer-Porter bottle according to the general procedure set forth above. One hundred mL water and 100 g (137 mL) decane containing 0.01 mol PdCl 2 , 0.05 mol heteropolyacid, 0.45 mol 1-butene were reacted for 2 hrs. at 80° and 100 psig. Analysis of the final product revealed a 1-butene conversion of only 3.3% with a selectivity to MEK of 90.5%.
The results of this experiment demonstrate the poor performance of the palladium/heteropolyacid catalyst system in two-phase medium in the absence of surfactant or boric acid component.
EXAMPLE V
A control run was carried out in which 2-butene was oxidized to methyl ethyl ketone utilizing the palladium chloride-heteropolyacid catalyst system in a two-phasee medium with cetyltrimethylammonium bromide (CTMAB) surfactant added. The reaction was carried out in a 500 mL Fischer-Porter bottle according to the general procedure set forth above. One hundred mL water and 100 g (137 mL) decane containing 0.01 mol PdCl 2 , 0.05 mol heteropolyacid, 0.004 mol CTMAB, and 0.47 mol 2-butene were reacted for 2 hrs. at 80° and 100 psig. Analysis of the final product revealed a 2-butene conversion of 64.2% with selectivity of 84.5% to MEK.
The results of this experiment demonstrate the operability of the palladium chloride-heteropolyacid catalyst for the oxidation of 2-butene to methyl ethyl ketone in the presence of a surfactant such as CTMAB.
EXAMPLE VI
A series of 1-butene oxidations were carried out utilizing the same catalyst charge for numerous recycles, occasionally recharging palladium (as noted in Table II below) to compensate for handling losses. All reactions were carried out using a 500 mL Fischer-Porter bottle containing 100 mL water, 100 g (137 mL) decane, 0.05 mol heteropolyacid, 0.25 mol H 3 BO 3 , and palladium in the amounts tabulated in Table II. Reactions were carried out for 2 hrs. at 80° and 100 psig according to the general procedure set forth above.
TABLE II______________________________________ Butene Butene Selectivity Charged, Conversion, to MEK,Run# PdCl.sub.2, mol mol mol % mol %______________________________________1 0.01 0.45 66.7 92.02 " 0.44 65.7 97.53 +.0001 0.45 82.0 97.04 " 0.45 59.3 99.15 +.0001 0.46 54.7 99.16 " 0.45 30.6 97.4______________________________________
These experiments demonstrate the operability of the process of this invention for the oxidation of 1-butene to methyl ethyl ketone in the presence of a palladium compound, a heteropolyacid and boric acid in two-phase medium. High butene conversions with excellent selectivity to MEK are obtained. These excellent results are maintained through several recycles of the catalyst.
EXAMPLE VII
A series of 2-butene oxidations were carried out utilizing the same catalyst charge for numerous recycles, occasionally recharging palladium (as noted in Table III below) to compensate for handling losses. All reactions were carried out using a 500 mL Fischer-Porter bottle containing 100 mL water, 100 g (137 mL) decane, 0.05 mol heteropolyacid, 0.25 mol H 3 BO 3 , and palladium in the amounts tabulated in Table III. Reactions were carried out for 2 hrs. at 80° and 100 psig according to the general procedure set forth above.
TABLE III______________________________________ Butene Butene Selectivity Charged, Conversion, to MEK,Run# PdCl.sub.2, mol mol mol % mol %______________________________________1 .01 0.47 87.5 86.82 " 0.44 79.3 88.73 +0.0001 0.45 73.0 92.94 " 0.45 63.8 95.35 +0.0001 0.45 44.1 97.46 " 0.45 40.8 96.3______________________________________
These experiments demonstrate the operability of the process of this invention for the oxidation of 2-butene to methyl ethyl ketone in the presence of a palladium compound, a heteropolyacid and boric acid in two-phase medium. High butene conversions with excellent selectivity to MEK are obtained. These excellent results are maintained through several recycles of the catalyst.
EXAMPLE VIII
A series of 2-butene oxidations were carried out utilizing the same catalyst charge for numerous recycles, occasionally recharging catalyst components (as not in Table IV below) to compensate for handling losses. All reactions were carried out using a 500 mL Fischer-Porter bottle containing 100 mL water, 100 g (137 mL) decane, 0.05 mol heteropolyacid, 0.25 mol H 3 BO 3 , and palladium and surfactant in the amounts tabulated in Table IV. Reactions were carried out for 2 hours at 80° and 100 psig according to the general procedure set forth above.
TABLE IV______________________________________ Butene Butene Con- Selectivity CTMAB, Charged, version, to MEK,Run# PdCl.sub.2, mol mol mol mol % mol %______________________________________1 0.01 0.004 0.52 51.9 91.32 " " 0.42 59.8 90.43 +0.0001 +0.00003 0.52 51.4 87.74 " " 0.47 58.9 91.15 +0.0001 +0.00003 0.44 77.3 89.36 " " 0.45 69.0 90.3______________________________________
These experiments demonstrate the operability of the process of this invention for the oxidation of 2-butene to methyl ethyl ketone in the presence of a palladium compound, a heteropolyacid, boric acid and a surfactant in two-phase medium. Excellent butene conversions with high selectivity to MEK are obtained through several recycles of the catalyst.
Reasonable variations, such as those which would occur to a skilled artisan may be made herein without departing from the scope of the invention. | A Pd/heteropolyacid/boric acid catalyst system, when used with proper diluents, improves the oxidation of olefins to ketones, while reducing scum and deposits on reactor surfaces. | 2 |
BACKGROUND AND SUMMARY OF THE INVENTION
The present invention relates generally to supporting devices for garments and more specifically to a supporting device for trousers which transfers the weight of the trousers to the small of the back and the hips of the wearer.
The cut of many trousers, for both males and females, results in a waistband which is positioned approximately at the waist of the wearer, i.e., above the wearer's hips. Whether or not a belt is worn, the full weight of the trousers must be supported from the waistband. The waistband must be tightened against the stomach sufficiently to support the trousers, or the trousers will have a tendency to slip down so that the waistband rests on the wearer's hips. These trousers often have an unfashionable look if they are worn other than where intended, and can be unsightly and uncomfortable when a belt is tightly cinched around the waist.
Both problems are especially acute for many overweight persons, especially those with protruding stomachs. In order to support the trousers in approximately the desired position, the waistband must be belted quite tightly, or the front portion of the trousers raised to where they will rest on the upper side of the stomach bulge. Otherwise, the waistband of the trousers tends to slip down in front to a position generally below the stomach bulge. This results in the trousers hanging improperly throughout their length, with the waistband being lower in front than in back.
Attempts have been made to overcome this problem in the past. Perhaps the best known example is the development of suspenders, which transfer the weight of the trousers to the shoulders while holding the waistband relatively level. The use of suspenders has a number of obvious drawbacks, including the fact that the suspenders are visible unless covered by a coat or other garment. Further drawbacks include the fact that the elastic material which generally must be used for suspenders can stretch or can be pulled out of shape, and the trousers may "ride up" in back when the wearer bends over. Additionally, many people are uncomfortable with the fact that the weight is being supported from the shoulders rather than at the waist/hip region of the body.
Various attempts have been made to provide a supporting device in which the weight of the trousers is supported on the hips while the waistband remains at the wearer's waist level. These attempts have included, for example, the use of long flexible rods which wrap around the wearer's hips and attach to the waistband at various points. Other attempted solutions to this problem include the use of a lower belt worn around the hips. Such an apparatus employs a plurality of stiff vertical members coupled to a second belt, which is in turn attached to the waistband of the trousers.
The solutions proposed by the prior art have several important drawbacks. Such previous solutions are difficult to adjust to various sizes. Devices presently known in the art are difficult and cumbersome to use, and are complicated in construction. This complexity deters the use of such devices, and makes them expensive to produce. Present devices are generally uncomfortable to wear, and some have relatively large mechanical parts which show through the trousers.
It is therefore an object of the present invention to provide a trouser support device which causes the weight of the trousers to rest partially on the wearer's hips and partially in the small of the back. It is a further object that such a trouser support device be simple to put on, comfortable to wear and inexpensive to manufacture. It is another object that such a support device not be visible when used.
In order to obtain these and other objects, a device constructed in accordance with the present invention has a flexible belt which is suitable for wearing about a person's hips. Two stiff support arms are pivotally coupled to either side of such belt, and are also pivotally coupled respectively a plastic strip on each side enclosed within to the waistband of the trousers. The weight of the trousers is transferred in part through the support arms and support belt to the hips of the wearer, and in part to the small of the wearer's back through the waistband of the trousers.
The novel features which characterize the present invention are defined by the appended claims. The foregoing and other objects and advantages of the invention will hereinafter appear, and for purposes of illustration but not of limitation, a preferred embodiment is shown in the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an exploded view of trouser support device constructed according to the present invention; and
FIG. 2 is a partially cutaway view of the device of FIG. 1 when assembled and worn with a pair of trousers.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The preferred embodiment of a device 10 constructed according to the present invention is shown in FIG. 1. A flexible belt 12, preferably made of leather or a similar material, has a plurality of, and preferably five (5) holes 14 on either side. These holes 14 are spaced about two inches apart, and preferably have metal reinforcing rings 16 inserted therein to prevent excessive wear of the belt 12 material. The belt 12 may be fastened in front by any means, but is preferably fastened by a nylon hook and eye fastener 18. An example of such a fastener 18 is the product Velcro, a nylon hook and eye fasterner, which allows the belt 12 to be quickly and easily fastened and unfastened but will stay firmly in place when desired.
Two support arms 20 are made of material which is stiff enough not to flex or bend appreciably from the weight of trousers 22, such as a stiffened plastic. These support arms 20 each have a hole 24 in the lower end, into which a bolt 26 can be inserted. For more adjustability, the support arms 20 may have a plurality of spaced holes 24 at various positions in their lengths. Each bolt 26 is fastened on the inside of the belt 12 by a nut 28, preferably of a type having a capped end and an internally threaded sleeve as shown. This sleeve projects through the belt hole 14 and support arm hole 24, and acts as an axle about which the support arm 20 can rotate.
A male engaging member 30 of a conventional snap fastener is attached to the upper end of each support arm 20. The female portions 32 of the snap fasteners are attached to the middle of waistband stiffeners 34. These waistband stiffeners 34 are attached to the waistband 36 of the trousers 22. These stiffeners 34 may be attached to the trousers 22 by any conventional means, such as insertion into slots in the waistband 36, or being relatively permanently affixed thereto such as by being sewn into the waistband 36. The prop fasteners provide for rotatably coupling the support arms 20 to the stiffeners 34 that are made of material stiff enough not to flex or bend appreciably from the weight of trousers 22, such as a stiffened plastic, and as such the stiffeners keep waistband the waistband 36 from peaking at the points of attachment. These waistband stiffeners 34 eliminate modifying (other than by opposite side three quarter inch vertical access slits inside of the waistband) the trousers to be supported and insures maintainance of a straight waistband line.
As shown more clearly in FIG. 2, the embodiment of FIG. 1 is used by strapping the belt 12 in place about the wearer's hips. The belt 12 is preferably located so that the front portion is below the stomach, and the middle portion rests slightly above the hips. The support arms 20 are positioned at the holes 14 desired by the wearer, but should preferably be selected at positions concentric with the hip joints of the wearer so as to provide greater mobility in bending, sitting and stooping. As will be described below, positioning the support arm 20 at a hole toward the front causes a greater portion of the weight of the trousers 22 to rest on the wearer's hips, while positioning such arms 20 toward the rear causes a greater portion of the weight of the trousers 22 to be borne at the small of the back. The waistband stiffeners 34, having been attached to the trousers 22, are snapped in place against the support arms 20.
Each support arm 20 is pivotally coupled at both ends, so that all weight borne by the support arm 20 is directly along its length. If the lower end of the support arm 20 is positioned more forwardly than the position shown in FIG. 2, it will be essentially vertical and virtually the entire weight of the trousers 22 will be transferred through the support arm 20 and the support belt 12 to the hips. When the lower end of the support arm 20 is preferably positioned as shown in FIG. 2, the weight of the trousers 22 is not supported vertically by the support arm 20, and there exists a moment about the lower axle of the support arm 20 in a forward direction (counterclockwise as shown in FIG. 2). A portion of the weight of the trousers 22 is transferred to the hips in a rearward direction through the support arm 20 and belt 12, while the remainder of the weight is transferred through the waistband and presses against the small of the back in a horizontal direction. Locating the lower end of the support arm 20 further to the rear results in a greater proportion of the trouser weight being suspended from the small of the back.
Positioning the support arms 20 approximately as shown in FIG. 2 is preferred, as experience has shown that such position results in a very comfortable distribution of weight and a good "hang" to the trousers 12. Of course, the plurality of holes 14 in the belt 12 allows the support arm 20 to be positioned to each wearer's personal taste, and in addition allows a relatively small number of standard sized devices 10 to fit persons of various sizes. As will be noted from the above description, the support device 10 is extremely simple and inexpensive to manufacture, as well as being simple to use and non-cumbersome. A single belt 12 can be used for all of a person's trousers, with snap fasteners 32 being permanently affixed to waistband stiffeners 34 within the inside of all trouser waistbands, or other mounting means can be temporairly or permanently attached to the inside of the waistband so that upper pivot connection of each support arm 20 is approximately two inches forward of the side seam of the trousers on each side of the trousers. The stiffeners 34, support arms 20, and bolts 26 and nuts 28 are identical on the left and right sides, and are easily obtained materials so that productions costs for the support device 10 are extremely low. The plasticstiffners 34 are inserted into each side of the waistband through a vertical slit approximately three quarters of an inch long approximately two inches in front of the side seam on each side of the trousers so that with the snap fastener 32 pivotal snapped engagement with male engagement member 30 through the vertical slit in the waistband on each side. This locates the pivot connection at the top of the support arms 20 forward of the pivot connection at the bottom of the support arms 20 as related to the user's body when the pivot axis at the bottom is positioned with pivot hole 14 properly in alignment substantially concentric with the transverse axis of the wearer's hip joints. Thus the advantageous "Z" like configuration is attained as shown in FIG. 2.
Because a device constructed as described above has minimal projection in a radial direction, the support device 10 does not show when worn. The belt 12, support arms 20 and stiffeners 34 all press closely to the wearer's body. Thus, the appearance of the trousers is greatly improved because they are worn as the designer intended, with no obvious extra support.
Although a preferred embodiment has been described in detail, it should be understood that various substitutions, alterations, and modifications may become apparent to those skilled in the art. These changes may be made without departing from the spirit and scope of the invention as defined by the appended claims. | A belt for supporting trousers has a lower adjustable supporting strap. Stiff members are attached to the waistband of the trousers. Supporting arms are rotatably coupled to the stiffened members and the supporting strap. When the trousers are worn, the weight is partially supported in the small of the wearer's back and partially on the wearer's hips by force transmitted through the support members. | 8 |
BACKGROUND OF THE INVENTION
[0001] This invention relates to a decorative paper which contains a pigment mixture of titanium dioxide and talc and the decorative coating materials obtained therefrom.
[0002] Decorative coating materials, so-called decorative sheets or decorative paper [paper impregnated with synthetic resin] is preferably used for surface coating in production of furniture and in completion of interiors. Decorative sheets are understood to be printed or unprinted sheets of paper impregnated with a synthetic resin and optionally treated at the surface. Decorative sheets are glued or bonded to a backing board.
[0003] Depending on the type of impregnation process, a distinction is made between decorative sheets with a thoroughly impregnated paper core and decorative sheets based on a preimpregnate, in which the paper is impregnated only partially online in the papermaking machine. Molded laminated materials (high-pressure laminates) are laminates produced by pressing several impregnated layered papers. The structure of these molded laminated materials consists in general of a transparent layer (overlay) which produces an extremely high surface stability, a decorative paper impregnated with a synthetic resin and one or more kraft papers impregnated with a phenolic resin. Molded fiber board and particle board as well as plywood can be used as the substrate for this.
[0004] In the laminates (low-pressure laminates) produced by the short-cycle method, the decorative paper impregnated with synthetic resin is pressed directly with a substrate, e.g., a particle board using a low pressure. The decorative paper used in the coating materials mentioned above is white or colored and may be with or without an additional imprint.
[0005] Special requirements are made of so-called decorative base paper such as high opacity for a better coverage of the substrate, uniform formation and grammage of the sheet for uniform resin uptake, high light stability, high purity and uniformity of the color for good reproducibility of the pattern to be printed, high wet strength for a smooth impregnation operation, suitable absorbency to achieve the required degree of resin saturation and dry strength which are important in re-rolling operations in the papermaking machine and in printing in the printing machine.
[0006] Decorative base paper is generally made of high-white sulfate pulp, mainly from hardwood pulp, up to 45% pigments and fillers and wet strength, retention agents and fixing agents. Decorative base paper differs from the usual paper in that it has a much higher filler content and there is none of the internal sizing or surface sizing which is usual in paper with the known sizing agents such as alkyl ketene dimers.
[0007] Opacity is one of the most important properties of decorative base paper. This characterizes the coverage with respect to the substrate.
[0008] A high opacity of the decorative base paper is also achieved by adding white pigments. Titanium dioxide is usually used as the white pigment. This pigment guarantees a high opacity and a good brightness and whiteness of the decorative base paper. However, the high price of titanium dioxide is a disadvantage.
[0009] Replacing some or all of the titanium dioxide with other white pigments has a negative effect on these properties. Matching of opacity can be achieved only by increasing the pigment content. However, the pigment content cannot be increased to an unlimited extent, because in this case, negative effects on the physical properties such as retention of the pulp suspension, strength, light-fastness and resin uptake can be expected.
SUMMARY OF THE INVENTION
[0010] The object of this invention is to make available an inexpensive decorative paper with a high opacity while at the same time having a reduced titanium dioxide content.
[0011] This object is achieved by a decorative base paper for decorative coating materials, wherein said decorative base paper contains a pigment mixture of a titanium dioxide and talc. The talc used according to this invention has a very narrow particle size distribution with a D50 of less than about 3 μm. This means that 50 wt % of the talc particles have a diameter of less than about 3 μm. Talc with a particle size distribution D50 of less than about 2 μm is especially preferred.
[0012] According to a further embodiment a decorative paper or decorative sheet is provided that includes the aforementioned decorative base paper.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0013] The specific surface area of the talc used according to this invention is greater than about 30,000 m 2 /kg, or according to an especially preferred embodiment it is greater than about 40,000 m 2 /kg. On the other hand, the specific surface area of traditional types of talc is in the range of 8,000 to 16,000 m 2 /kg. The specific surface area was determined according to DIN 66,126.
[0014] The amount of talc in the pigment mixture is preferably 0.1 to 25 wt %, based on the total pigment content.
[0015] The titanium dioxide preset in the pigment mixture used in the decorative base paper according to this invention may be a titanium dioxide conventionally used in decorative paper. Such titanium dioxides are available commercially and may be used in the rutile or anatase modification. Such titanium dioxides of the rutile type are especially preferred.
[0016] Other fillers such as zinc sulfide, calcium carbonate, kaolin or mixtures thereof may be used.
[0017] The amount of filler in the decorative base paper may be up to 55 wt %, in particular 11 to 50 wt % or 20 to 45 wt %, based on the weight of the paper. The weight of the decorative base paper according to this invention may be in the range of 30 to 300 g/m 2 and is usually 40 to 200 g/m 2 . The weight is selected as a function of the specific application.
[0018] Softwood pulp (long-fiber pulp) or hardwood pulp (short-fiber pulp) may be used as the cellulose pulp for producing the decorative bulk paper according to this invention. It is also possible to use cotton fibers or mixtures of the types of cellulose mentioned above. For example, a mixture of softwood pulp and hardwood pulp in a ratio of 10:90 to 90:10 or mixtures of softwood pulp and hardwood pulp in a ratio of 30:70 to 70:30 are especially preferred. The pulp may have a degree of beating of 20 to 60 SR according to Schopper-Riegler.
[0019] The cellulose pulp mixture preferably has a cationically modified cellulose fiber content of at least 5 wt %, based on the weight of the cellulose mixture. A content of 10 to 50 wt %, in particular 10 to 20 wt % of the cationically modified cellulose in the cellulose pulp mixture has proven to be especially advantageous.
[0020] Cationically modified cellulose pulps are known from the journal Das Papier , volume 12 (1980), pp. 575-579, for example.
[0021] In a special embodiment of this invention, the cationically modified cellulose contained in the paper pulp has an effective cationic charge of 20 to 300 mmol/kg pulp, determined according to the internal method no. 4 of the Technical University of Darmstadt. Cellulose pulp fibers with a charge density of 30 to 100 mmol/kg are preferred. The term “effective cationic charge” is understood to refer to a charge density which has been balanced with the charge density of the non-cationized cellulose pulp. The charge density of the cellulose pulp depends on the amount of cationic agent to be used. The amount of cationizing agent may be 0.005 to 200 g/kg cellulose pulp.
[0022] The cationic modification of the cellulose pulp fibers may be accomplished through reaction of the fibers with epichlorohydrin resin and a tertiary amine or by reaction with quaternary ammonium chlorides such as chlorohydroxypropyl-trimethyl-ammonium chloride or glycidyltrimethyl-ammonium chloride.
[0023] In a preferred embodiment of this invention, cellulose pulp fibers that have been cationically modified by an addition reaction of quaternary ammonium compounds having glycidyl functional groups with hydroxyl groups of cellulose are used.
[0024] The decorative bulk paper according to this invention may contain wet strength agents such as polyamide/polyamine-epichlorohydrin resin, other polyamine derivatives or polyamide derivatives, cationic polyacrylates, modified melamine-formaldehyde resin or cationized starches. These are added to the pulp suspension. Likewise, it is also possible to add retention aids and other substances such as organic and inorganic colored pigments, dyes, optical brighteners and dispersants.
[0025] The decorative bulk paper according to this invention can be produced on a Fourdrinier papermaking machine or a Yankee papermaking machine. To do so, the cellulose pulp mixture may be pulped to a degree of beating of 30 to 45 SR at a pulp density of 2 to 4 wt %. In a mixing vat, fillers such as titanium dioxide and talc, and wet strength agents are added and mixed well with the cellulose pulp mixture. The resulting thick pulp is diluted to a pulp density of approximately 1 wt %, and other additives such as retention aids, foam suppressant, aluminum sulfate and other additives as listed above are added as needed. This thin pulp is passed through the headbox of the papermaking machine and sent to the wire section. A fiber nonwoven is formed, yielding after drainage the decorative base paper which is then dried.
[0026] To produce decorative paper, the decorative base paper is impregnated with the conventional synthetic resin dispersions for this purpose. The conventional synthetic resin dispersions for this purpose include, for example, those based on polyacryl or polyacrylmethyl esters polyvinyl acetate, polyvinyl chloride or synthetic resin solutions based on phenol-formaldehyde precondensates, urea-formaldehyde precondensates or melamine-formaldehyde precondensates or their compatible mixtures.
[0027] The impregnation may also be accomplished in the size press of the papermaking machine. The decorative base paper can be impregnated in such a way that the paper is not completely impregnated. Such decorative paper is also known as a preimpregnate. The amount of resin introduced into the decorative base paper by impregnation in this case amounts to 25 to 30 wt %, based on the weight of the paper.
[0028] After drying, the impregnated paper can also be coated and printed and then applied to a substrate such as a wooden board. The coated and optionally printed products are generally known as decorative sheets.
[0029] The following examples are presented to further illustrate this invention. Amounts given in percent by weight are based on the weight of the cellulose pulp, unless otherwise indicated.
EXAMPLE 1
[0030] A cellulose pulp mixture consisting of 70 wt % eucalyptus pulp and 30 wt % softwood sulfate pulp was mixed with 0.6 wt % epichlorohydrin resin as the wet strength agent, 0.11 wt % of a retention aid and 0.03 wt % of a foam suppressant as the basic mixture. The latter three percentages are based on the weight of the pulp. The pH of this mixture was adjusted to 6.5 with aluminum sulfate. This mixture was then mixed with a pigment mixture of 55.8 wt % titanium dioxide and 5.2 wt % talc. Using a Fourdrinier papermaking machine, a decorative paper with a grammage of 105 g/m 2 was produced. The titanium dioxide content was 33.5 g/m 2 (31.9 wt %) and the talc content was 3.1 g/m 2 (2.95 wt %). The talc had a particle size distribution D50 of 1.9 μm and a specific surface area of 44,300 m 2 /kg.
EXAMPLE 2
[0031] A pigment mixture of 50.3 wt % titanium dioxide and 14.7 wt % talc was added to the basic mixture from Example 1. A decorative paper with a grammage of 105 g/m 2 was produced with a Fourdrinier papermaking machine. The titanium dioxide content was 30.2 g/m 2 (28.8 wt %) and the talc content was 8.8 g/m 2 (8.4 wt %). The talc had a particle size distribution D50 of 1.9 μm and a specific surface area of 44,300 m 2 /kg.
EXAMPLE 3
[0032] A pigment mixture of 64.5 wt % titanium dioxide and 3.3 wt % talc was added to the basic mixture from Example 1. A decorative paper with a weight of 105 g/m 2 was produced on a Fourdrinier papermaking machine. The titanium dioxide content was 38.7 g/m 2 (36.5 wt %) and the talc content was 2.0 g/m 2 (1.9 wt %). The talc had a particle size distribution D50 of 1.9 μm and a specific surface area of 44,300 m 2 /kg.
EXAMPLE 4
[0033] A pigment mixture of 53.9 wt % titanium dioxide and 11.3 wt % talc was added to the basic mixture from Example 1. A decorative paper with a weight of 105 g/m 2 was produced on a Fourdrinier papermaking machine. The titanium dioxide content was 32.3 g/m 2 (30.8 wt %) and the talc content was 6.8 g/m 2 (6.5 wt %). The talc had a particle size distribution D50 of 1.5 μm and a specific surface area of 47,100 m 2 /kg.
Comparative Example 1
[0034] As Comparative Example 1, only a 62 wt % titanium dioxide dispersion was added to the basic mixture from Example 1. A decorative paper with a weight of 120 g/m 2 and a titanium dioxide content of 37.2 g/m 2 (31 wt %) was produced using a Fourdrinier papermaking machine.
Comparative Example 2
[0035] A pigment mixture of 50.8 wt % titanium dioxide and 14.4 wt % talc was added to the basic mixture from Example 1. A decorative paper with a weight of 105 g/m 2 was produced on a Fourdrinier papermaking machine. The titanium dioxide content was 30.5 g/m 2 (29 wt %) and the talc content was 8.7 g/m 2 (8.3 wt %). The talc had a particle size distribution D50 of 3.7 μm and a specific surface area of 8,600 m 2 /kg.
[0036] The opacity of paper samples from Examples B1 through B4 and Comparative Examples V1 and V2 was determined according to DIN 53,146 by using an ACE color measuring instrument from Data Color. The titanium dioxide content of the decorative base paper was determined according to DIN 54,370. The results are summarized in the following table.
Talc content, based on Opacity total pigment Talc content Sample (%) (%) (g/m 2 ) B1 92.68 8.5 3.1 B2 92.55 22.6 8.8 B3 92.61 4.9 2.0 B4 92.62 17.3 6.8 V1 92.71 0.0 0.0 V2 90.28 22.2 8.7
[0037] The results of the opacity measurements show that a high opacity can be achieved with the talc used according to this invention even with a greatly reduced titanium dioxide content. | A decorative base paper for decorative coating materials contains a pigment mixture of titanium dioxide and talc, wherein the talc has a particle size distribution D50 of less than approximately 3.0 μm, and both the decorative base paper and the decorative paper have a high capacity. | 3 |
RELATED APPLICATIONS
This application is related to copending U.S. patent applications (1) Ser. No. 08/749,688 entitled "STATELESS DATA TRANSFER PROTOCOL WITH CLIENT CONTROLLED TRANSFER UNIT SIZE", and (2) Ser. No. 08/749,689, entitled "STATELESS RATE-CONTROLLED DATA TRANSFER PROTOCOL", which were filed concurrently herewith and are incorporated herein by reference.
FIELD OF THE INVENTION
The present invention relates generally to data transfer protocols and, in particular, to a binary large asset stateless transfer (BLAST) protocol for transferring data files in a client-server environment.
BACKGROUND OF THE INVENTION
Referring to FIG. 1, as is well known, computer systems attached to data networks 10 are often connected in a client-server fashion, with a single server 12 servicing requests from multiple clients 14. The number of clients 14 that can be serviced by a single server 12, and thus the cost-effectiveness of the system, is dependent on how efficiently each transaction can be processed.
There are two chief costs to be considered in the design of such a system. One is the computational efficiency of the transfer protocol itself, and the other is the effective utilization of the network 10 between the client 14 and the server 12.
The computational efficiency of the protocol is a measure of the amount of work to be performed by the endpoints, namely the client 14 and server 12, in order to reliably transfer a given amount of information. The focus of attention is on the work required by the server 12, since it is processing requests from a potentially very large number of clients 14. The less work that needs to be performed by the server 12, the lower the cost to the system for providing the service.
From the point of view of the server 12, there are two components to the computational cost of a data transfer protocol. The first is the cost of actually transferring the desired data, and the second is the protocol overhead, which includes every CPU cycle executed which is not directly involved with transmitting the data. This may include connection setup, acknowledgement processing, retransmission, and connection teardown. It also includes the cost of processing (e.g., interrupts and protocol stack overhead) each unique incoming and outgoing PDU (protocol data unit) and any associated header.
While there is a minimum cost of the data transfer itself that cannot be avoided, the protocol overhead associated with the transfer can be reduced.
An independent problem from computational efficiency is network efficiency, which is a measure of how much useful data is carried through the network 10 to the destination as compared to how much was offered to it. Data loss, typically caused by network congestion, is a factor in any network 10 with shared components, where it is possible for instantaneous network load to exceed capacity. In a reasonably engineered network 10, congestion is typically bursty, corresponding to burstiness in the offered data traffic.
There are several approaches to increasing protocol efficiency, particularly be decreasing the protocol overhead. One way to decrease protocol overhead is to increase the size of outgoing PDUs. This amortizes the per-PDU cost over a larger amount of data and requires fewer PDUs to complete the transfer, reducing the total cost of the transfer. Trivial File Transfer Protocol (TFTP), which is based on the well known User Datagram Protocol over the Internet Protocol or UDP/IP, is an example of a protocol that allows an increase in its PDU size to gain efficiency.
Another way to decrease protocol overhead is to reduce the number of incoming PDUs. For example, a TFTP file transfer requires one incoming acknowledgement PDU for each outgoing data PDU. This results in a high transfer cost to the server. In contrast, the TCP-based FTP uses a windowing scheme, where multiple outgoing PDUs may be acknowledged by a single incoming PDU.
Yet another way involves selective retransmission. Windowed protocols that use a go-back-n retransmission scheme can cause successfully received data to be discarded and retransmitted. By causing only the lost data to be retransmitted, unnecessary work at the server can be avoided. Protocols such as XTP implement selective retransmission.
Some transport mechanisms, such as a connectionless transport mechanism, are inherently simpler and more efficient than others. A connectionless, non-guaranteed service like UDP/IP, (as used by TFTP) may be considerably more efficient than reliable, connection-oriented TCP or ISO TP4 for data movement. However, since UDP does not provide the same traffic integrity guarantees as TCP, the responsibility for ensuring reliable transfer lies with the file transfer mechanism itself rather than the underlying system.
All else being equal, increasing either the PDU size or the acknowledgement window increases the chance of network congestion. More data is being sent in each burst to the network. Unless there is some sort of way to limit this traffic, network congestion will increase, leading to data loss and more retransmission, leading back to more work for the server. Unfortunately, most solutions which increase network efficiency tend to increase the computational cost of moving data.
Though designed as an end-to-end mechanism to prevent message loss due to buffer depletion, modified flow control mechanisms can be used to aid network stability. TCP takes an approach that dynamically varies the acknowledgement window based on end-to-end message loss. This can detect and recover from network congestion, but at the cost of considerable overhead on the part of the sender, and at the cost of needing to induce network congestion before it can be detected.
Another solution to network congestion is explicit peer-to-peer rate/flow control, as exemplified in the ATM ABR (available bit rate) scheme. In this scheme, the instantaneously available network bandwidth is advertised to the endpoints, which are expected to limit output accordingly. Unfortunately, this capability is not widely available and is computationally expensive both for the server and the network.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a new and improved data transfer protocol and, in particular, a data transfer server implementing the protocol.
The invention, therefore, according to a first broad aspect provides a method of operating a data transfer server, comprising the steps of: defining a circular ordering of individual scheduling timeslots having zero or more download records, each of which includes information of remaining data to transfer from identified data, a transfer rate and a destination address; selecting in sequence, at a predetermined rate, the individual scheduling timeslots; and servicing, responsive to the selected timeslot having at least one download record, each record therein by: (i) sending, to the destination address, a download message which includes a block of data extracted from the identified data, based on the remaining data information; (ii) updating the remaining data information to reflect the block of data that was sent; and (iii) resheduling, based on the transfer rate and the predetermined rate, the download record into an appropriate one of the scheduling timeslots; whereby, in the servicing of each download record, successive download messages having respective blocks of data extracted from the identified data are sent at a rate less than or substantially equal to the transfer rate in that record.
In accordance with a second broad aspect of the invention, there is provided a data transfer server, comprising: means for defining a circular ordering of individual scheduling timeslots having zero or more download records, each of which includes information of remaining data to transfer from identified data, a transfer rate and a destination address; means for selecting in sequence, at a predetermined rate, the individual scheduling timeslots; and means for servicing, responsive to the selected timeslot having at least one download record, each record therein, the means for servicing including: (i) means for sending, to the destination address, a download message which includes a block of data extracted from the identified data, based on the remaining data information; (ii) means for updating the remaining data information to reflect the block of data that was sent; and (iii) means for resheduling, based on the transfer rate and the predetermined rate, the download record into an appropriate one of the scheduling timeslots; whereby, in the servicing of each download record, successive download messages having respective blocks of data extracted from the identified data are sent at a rate less than or substantially equal to the transfer rate in that record.
A binary large asset stateless transfer (BLAST) data communications protocol, embodying the present invention, provides a simple, reliable and highly scaleable data transfer facility in a digital data network, interconnecting a file server and a client. A connectionless, unacknowledged data transfer protocol minimizes resource utilization at the data server and is combined with source rate control to reduce congestion in the intervening network.
The BLAST protocol is focused on making the function of the file server as simple as possible. To that end, a system was designed with the following features.
A connectionless transport mechanism is used, to eliminate any overhead in connection establishment and maintenance.
PDU traffic to the server is reduced by using an unacknowledged transfer protocol requiring, in most cases, only a single request to initiate the transfer of all of the data. Transfer time is made largely independent of network end-to-end delay.
Network congestion is limited by regulating the data transfer based on a rate-control parameter. In order to accommodate widely varying capabilities of clients, the requesting client specifies the maximum PDU size and PDU rate in the data request. The server may further reduce these maximums according to its own requirements.
The loss of data is detected by the client and selectively re-requested by the client. The re-requests are completely unique data requests to the server, eliminating any need for client state information to be kept or correlated at the server.
The client has the responsibility to correlate re-requested segments with the original request, and verifying the data is still current.
Client heuristics may be applied to adjust PDU size and rate for requests if patterns of message loss indicate there is network congestion.
The basic rate-control scheme of BLAST is applicable to any data transfer, not just reliable file transfer. This includes the area of streaming video or voice protocols.
BLAST combines an unacknowledged, stateless protocol to increase server scalability; rate control to minimize potential of network congestion; and responsibility for reliable transfer residing in the client.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be better understood from the following description of a binary large asset stateless transfer (BLAST) protocol, together with reference to the accompanying drawings in which:
FIG. 1 is a schematic representation of a prior art client-server environment;
FIG. 2 is a structural representation of a message header in the BLAST protocol;
FIG. 3 is a structural representation of a GetFilesize message in the BLAST protocol;
FIG. 4 is a structural representation of a FilesizeData message in the BLAST protocol;
FIG. 5 is a structural representation of a DownloadStart message in the BLAST protocol;
FIG. 6 is a structural representation of a DownloadData message in the BLAST protocol;
FIG. 7 is a timing graph illustrating protocol behaviour during successful transfer;
FIG. 8 is a timing graph illustrating protocol behaviour during errored transfer;
FIGS. 9A, 9B, 9C, 9D, and 9E, illustrate client processing of downloaded data PDUs;
FIG. 10 is a schematic representation of an implementation of the BLAST server;
FIG. 11 illustrates exemplary pseudocode whereby a Request Handler task may be implemented in the BLAST server; and
FIG. 12 illustrates exemplary pseudocode whereby a PDU Scheduler task may be implemented in the BLAST server.
DETAILED DESCRIPTION
Having regard to FIG. 1, a binary large asset stateless transfer (BLAST) protocol, in accordance with the invention, provides a mechanism for transferring data files from a server 12 to any of a plurality of clients 14 which communicate through signalling carried by a data network 10. The server 12 and clients 14 are representative of typical data processing platforms suitable for the stated purposes. The data network 10 may be any conventional data communications technology, examples for which include frame relay or asynchronous transfer mode packet switched networks, and an Ethernet local area network running over which is the Internet protocol (IP). The BLAST protocol may be stacked on the network particular protocol(s) to effect the signalling exchanges between the server 12 and each client 14.
The BLAST protocol characterizes a stateless, rate-controlled request/response file transfer protocol. A request for one or many files, in whole or in part, is sent from a particular client 14 to the server 12. The request is identified by a client-unique transaction ID.
The request specifies not only the file(s) to be downloaded, but also includes information that tells the server 12 how the file is to be delivered. This includes the maximum size of an individual data packet and the maximum rate at which the packets can be processed. This is to accommodate a wide range of client configurations. The server 12, upon receiving a request, may further reduce the size and rate of data packets that will be used for the transfer, depending on the current loads of both the server 12 and the network 10. The server 12 then schedules the request and begins transmitting sequential data packets, containing the client-unique transaction ID, at the appropriate rate.
The regular stream of data packets arrives at the client 14 and are assembled into the original file. Each packet identifies its position in the file, and so can be handled independently of any other. There are no acknowledgements of any kind. The server 12 does not know or care whether the individual packets arrive at the client 14. Since the server 12 may be responsible for servicing requests from a very large number of clients 14, the reduction in message load greatly improves the scalability of the protocol. When the data specified in the original request has been sent, the transaction is completed from the server's point of view.
Data integrity is managed by the client 14. The client 14 must examine the received data and decide how to proceed. If there are `gaps` in the received data, as will be the case where there is message loss, the client 14 must initiate a new request for the missing data. There are many possible heuristic algorithms that can be used by the client 14 to get the missing data. It may wait until the original request is completed before rerequesting the data, or it may rerequest as soon as it notices a gap in the file. It might do a request for each gap, it might group gaps together, or it might simply rerequest the whole file. If the missing data exceeds a certain threshold, then network congestion can be assumed, and the rerequests can be made with a lower rate and/or a smaller data size specified. At the server 12, each rerequest by the client 14 is seen as a completely new request. There is no relationship known at the server 12 between any two past, present, or future requests. This further reduces the complexity, and improves the scalability of the server 12.
Signalling between the server 12 and each client 14 to effect the BLAST protocol is implemented by various messages which are transmitted therebetween, via the network 10. Particular embodiments of these BLAST protocol messages are described below and illustrated in FIGS. 2 to 6. Though the messages described pertain to a specific UDP/IP-based implementation of the BLAST protocol, it should be understood that nothing restricts this from being implemented over any other protocol stack, or in other operating environments. Similarly, PDU data field sizes are shown as present in this implementation, but are not necessarily restricted to the indicated size which may be adapted to satisfy requirements of the particular application.
Referring to FIG. 2, every BLAST protocol message shares a common header, identified herein as messageHeader, to simplify message interpretation. The messageHeader defines a set of parameters at the start of each message sent between the BLAST server and client. Fields forming part of the messageHeader include:
version--Parameter identifies a protocol version number which is used to ensure compatibility of messages.
messageID--A message type identifier parameter.
messageLength--Parameter indicates the total length of the entire message in bytes, including the message header 20.
transactionID--An arbitrary client assigned parameter used to associate data blocks with their respective requests.
Referring to FIG. 3, a GetFilesize message is illustrated. This message requests that the server reply with the size of the requested file, so that the client can ensure sufficient resources are available and allocated to receive it. Fields forming part of the GetFilesize message include:
messageHeader--Contains parameters as described above in connection with FIG. 2. In particular, the messageID parameter, for example, equals 00F5 Hex by which value the GetFilesize message is identified.
destinationAddress--Parameter identifies the IP address of the client.
destinationport--Parameter identifies the UDP port of the client.
fileDescriptorLength--Parameter indicates the length of the fileDescriptor in bytes.
fileDescriptor--Parameter identifies the requested file by providing a null-terminated full pathname of the file to be transferred.
Referring to FIG. 4, a FilesizeData message is illustrated. This message is a reply sent from the server to the client to satisfy the GetFileSize request message. Fields forming part of the FilesizeData message include:
messageHeader--Includes parameters as described above in connection with FIG. 2. In particular, the messageID parameter, for example, equals 00F6 Hex by which value the FilesizeData message is identified.
filesize--The size of the file, specified in the GetFilesize message, in bytes. If the file could not be found in the BLAST filesystem, the filesize will be 0 .
Referring to FIG. 5, a DownloadStart message is illustrated. This message is sent from the client to the server to initiate the data transfer for a requested file. Fields forming part of the DownloadStart message include:
messageHeader--Contains parameters as described above in connection with FIG. 2. In particular, the messageID parameter, for example, equals 00F3 Hex by which value the DownloadStart message is identified.
blockSize--Parameter indicates a maximum PDU (i.e., data block or packet) size for the server to use.
startByte--Parameter provides an offset within the file at which byte of data transfer is to begin (i.e., the first byte to send). The beginning of the file has an offset value of 0.
numBytes--Parameter indicates the total number of bytes of the file to send. A value of 0 indicates the entire file, or remainder of the file starting from the offset byte position when the offset parameter is greater than 0.
destinationAddress--Parameter identifies the IP address of the download client.
destinationport--Parameter identifies the UDP port of the download client.
delay--Parameter indicates a minimum delay in micro-seconds between sending successive data PDUs.
fileDescriptorLength--Parameter indicates the length of the fileDescriptor in bytes.
fileDescriptor--Parameter identifies the requested file by providing a null-terminated full pathname of the file to be transferred.
Referring to FIG. 6, a DownloadData message is illustrated. This message contains the actual data for the file transfer. The blocks of data are divided into the blocksize bytes of data, as specified in the DownloadStart message, and sent in order to the client. Fields forming part of the DownloadData message include:
messageHeader--Contains parameters as described above in connection with FIG. 2. In particular, the messageID parameter, for example, equals 00F4 Hex by which value the DownloadData message is identified.
firstByte--Parameter provides an offset into the file for the first byte of this data block. An offset value of 0 corresponds to the first byte in the file.
numBytes--Parameter indicates the number of data bytes in this block.
edition--Parameter identifies a version number of the file being downloaded. This allows the client to ensure that rerequests are being made from the same file as an initial request.
data--This parameter is the block of data payload being carried by this message.
Operation of the BLAST protocol will now be described with reference to FIG. 7 which illustrates protocol behaviour during a successful transfer.
The BLAST client is invoked when a data transfer from the server is required. At any time, but typically before a transfer request, the client may optionally make a request to the BLAST server for data file size information. An appropriate GetFilesize message is constructed and sent. In reply, the server sends a FilesizeData message providing the size information in respect of the file identified in the GetFilesize message. Depending on the implementation environment, this size information may be required for buffer allocation in order to ensure sufficient memory is available before a transfer or to return the information directly to the ultimate user.
To initiate a data transfer, the client sends a request, specifically the DownloadStart message, to the server containing the desired file name, the bytes of the file that are to be transferred, and the maximum PDU size and rate that are to be used in the transmission. A timer is then set by the client to await the arrival of the first incoming data PDU, specifically a first DownloadData message. The value of the timer should be relatively large, on the order of seconds, in order to avoid prematurely giving up on the request. If the timer times out, there are three possibilities. Either the original request was lost in the network, the request was discarded by the server due to overload, or the data PDUs are in transit. In the first two cases, the behaviour of the client will be to retry the request anyway, increasing the timeout with each retry. The consequences of waiting too little outweigh the cost of waiting too long.
If the request was successful, data PDUs will begin arriving in successive DownloadData messages which the server sends periodically until the transfer is finished. Each DownloadData message identifies its position in the file, and the respective data blocks may be placed directly into a buffer by the client. A record of the data PDUs received is maintained by the client. The mechanism for detection of the end of the transfer is left to the client. This can be detected by the arrival of the last requested byte of the file, or by the failure to receive data for a certain interval.
With reference to FIG. 8, detection of any data loss and a re-request strategy is up to the client. An implementation might have the client watching for gaps in the received data, and re-requesting the missing data either before the initial transfer is even complete or wait until the initial transfer is finished. The cumulative transfer rates of running initial requests and re-requests concurrently must of course be within the bounds of the clients PDU processing capabilities and the capacity of the intervening network. The re-request involves the client sending another DownloadStart message which requests the same data file as in the initial request but indicates that the server only transfer the data starting at an offset from the first byte of that file, corresponding to the missing block of data. In the exemplary scenario depicted by FIG. 8, the DownloadStart message requests the remainder of the file (beginning with the missing block), responsive to which the server sends two successive DownloadData messages, the first of which containing the data block that was previously missing.
When re-requested data is received, the client must examine the edition code of the file. This is used to ensure that the file did not change between the original request and the re-request. If the edition code has changed, the client assumes that the entire transfer has been invalidated and must begin anew.
Detection of data loss by the client will be explained in more detail, with reference to FIG. 9. In FIG. 9A, three successive data PDUs (i.e., DownloadData messages) have been successfully received, which contained the first to N bytes of the data file being transferred. As described above, each data PDU, for the block of data therein, specifies the offset into the data file of the first byte of that data block and also the size of that data block. The client can then determine whether the next received data PDU is contiguous based on the offset and size parameters from the prior (last received) PDU. For example, such may simply involve calculating from the start byte offset and the size parameters, an offset value for the end byte of the received data block, in terms of the end byte position within the data file, and comparing the calculated end byte offset with the offset parameter for the start byte taken from the next received data PDU. If the new start byte is contiguous with the previous end byte, the two ranges are coalesced. As illustrated in FIG. 9B, the next PDU (N+1..M) having N+1 to M bytes of data payload arrives and, its payload is inserted into the correct position of the buffer. If the new start byte is not contiguous with the previous end byte, we have identified a missing range of bytes. In FIG. 9C, data PDU (P..Q) arrives. Missing data (M+1..P-1) is detected. If desired, a new download request can be generated immediately for the missing range, or the client can wait until all frames have arrived and decide what needs to be re-requested. In the simplest case, the whole file could be requested again. For example, in FIG. 9D, three more data PDUs arrive, including the last byte of the requested transfer. The missing data is re-requested, and in FIG. 9E, data PDU (M+1..P-1) is received. The transfer is now complete.
With regard to FIG. 10, a particular implementation for the functionality of the BLAST server 12 is illustrated. The BLAST server 12 may be implemented by a conventional data processing platform, having a configuration that includes a primary storage 20 on which data files are maintained and a secondary storage as a file cache 22 which provides faster access to files during transfer. A Protocol Stack 24 provides both a physical network interface and stacked on which may be various levels of communications protocols to effectively communicate through the network (10 in FIG. 1), whereby the various BLAST protocol messages, in accordance with this invention, are exchanged with clients of the server 12. A Request Handler 26 is responsible for processing any received client requests, and may be implemented as a software task for which exemplary pseudocode is illustrated in FIG. 11. A PDU Scheduler 28 functions to effect delivery of the processed requests, and includes a timer 30 and scheduling queue 32. The PDU Scheduler 28 may also be implemented as a software task for which exemplary pseudocode is illustrated in FIG. 12.
In operation, the BLAST server 12 is idle until either a filesize request or download request, respectively embodied by a GetFilesize message and a StartDownload message, is received via the Protocol Stack 24, by the Request Handler 26. If the server 12 is overloaded, the determination of which is left to the Request Handler 26, then the request is silently discarded.
If the request is for a filesize, the available filesystem on the primary storage 20 is searched for the file. If the file is found, a filesize response is constructed by the Request Handler 26 and sent, containing the size of the file. If the file is not found, a filesize response is still constructed and sent, but contains a filesize of zero. It is noted that a file of size zero is not downloadable.
If the request is for a file download, and the file exists, then the Request Handler 26 begins preparation for download. The server 12 must have ready access to the download data during the transfer, and therefore, files are first loaded into the cache 22 to ensure such. The file cache 22 is not required, but is consistent with the overall goal of minimizing server workload and the preferred implementation encompasses a cache. If the most recent version of the file is not already present in the cache 22, it is preloaded into the cache 22 before the transfer begins. If an older version of the file is in the cache 22 and it is not in use, it will be replaced. If an older version of the file is in the cache 22 and is in use, that file will be tagged for discard as soon as the current download is completed.
If the cache 22 is full, and there are cache entries not currently being used, determination of the file to replace is done using a least-recently used algorithm. The size of the cache 22 may also be varied to accommodate more files. However, if the cache 22 is full, incoming requests for files not in the cache must be discarded. If an application environment consists of large numbers of homogeneous clients which tend to request the same set of files, cache replacement should be infrequent even with a fairly small cache 22.
The Request Handler 26 of the BLAST server 12 generates a unique edition number every time a file is loaded into the cache 22 and stores this edition number with the cached file, so that it is consistent for the lifetime of that cached file. During the transfer, this edition number is placed by the PDU Scheduler 28 into each data PDU, embodied by a DownloadData message, to allow the client to ensure that original requests and re-requests were serviced from the same underlying data. If a cache system is not used, then some other value must be provided for an edition number, such as, a file timestamp to ensure that the client can differentiate between different vintages of files with the same name.
The download request contains a client-specified maximum PDU size and minimum inter-PDU arrival time. These values are examined by the BLAST server 12, and may be adjusted downwards, based on server or network capabilities or conditions. The maximum PDU size may be adjusted downwards, and the minimum inter-PDU arrival time may be adjusted upwards. The PDU inter-arrival time is adjusted to an appropriate value for the configuration of the server platform. For instance, if the server 12 cannot reliably schedule PDUs at the requested intervals, then the value may be adjusted accordingly. These values may also be subject to some server-defined valid range of values, for example, multiple predetermined rates from which a particular rate may be selected by a client.
In the preferred implementation, the server 12 also has some knowledge of the capabilities and current condition of the server platform and of the capability and topology of the intervening network, and can further discard requests based on these. For example, servicing a large number of concurrent requests from one region of the network could overload that part of the network, even if each individual download is rate controlled, and cause the network congestion that the rate control scheme tries to prevent. Ideally, situations like this may be predicted by the server 12 and requests can be discarded appropriately. It is noted that filtering download requests or even maintaining a count of concurrent transfers requires some internal server state information to be maintained. However, the BLAST transfer protocol is still stateless with respect to individual clients and individual requests.
When the file is prepared for transmission, a record containing the particulars of the requested download is created and placed into the PDU scheduling queue 32 by the Request Handler 26. Individual download record entries in the PDU scheduling queue 32 are identified by reference 36.
The PDU scheduling queue 32 may be constructed as a circular queue of scheduling timeslots 34, each of which is a data structure formatted as a list of download records 36. However, a timeslot 34 may have a list which is empty when there are no download records to process. The download records 36 represents downloads in progress and each record 36 contains the file identifier, the PDU size and interval, the destination client address and port, the client unique transaction ID, and the remaining bytes to be sent for that download.
The minimum size of the PDU scheduling queue 32 is determined by granularity of the timer 30 (i.e., interval between timer ticks) and a maximum inter-PDU delay allowed by the server 12. There must be more scheduling timeslots 34 than results from dividing the maximum inter-PDU delay by the slot granularity, in order to ensure that rescheduling a download record 36 for the maximum inter-PDU delay does not result in it wrapping around the circular queue 32.
At periodic intervals, according to the minimum granularity of the timer 30 used by the PDU Scheduler 28, each timeslot 34 in the PDU scheduling queue 32 is checked, in sequence, for any download records 36 to be serviced. If there are no download records 36 present in a particular timeslot 34, there is no work to be done and the PDU scheduler 28 sleeps until the next timer tick, responsive to which the following timeslot 34 is checked.
If there are download records 36 present, each download record 36 in turn is retrieved and serviced. Servicing each download record 36 consists of taking a block of data, according to the PDU size and remaining bytes information in that record 36, from the identified file and sending the data block as the next data PDU for that download. If the last PDU for a download has been sent (i.e., transfer of all data in the identified file has been completed), the download record 36 is discarded. If the download is not complete, the download record 36 is updated and rescheduled into the next appropriate timeslot 34 in the PDU scheduling queue 32, determined from the PDU rate contained in the download record 36.
Depending on the number of downloads allowed to proceed at once and the granularity of the timer 30 (i.e., time interval between successive ticks), it may be possible that processing all the download records 36 attached to a particular PDU scheduler timeslot 34 takes longer than the time available. For example, the server 12 is still processing download records 36 at timeslot N when the timer 30 ticks whereby it is time to process slot N+1. This can be considered an instantaneous overload of the server 12, and repeated occurrances of this condition may be used to adjust the request discard policy for future requests. When this occurs, the server 12 should finish processing slot N and move immediately to slot N+1, until it has caught up.
Even though the server rate controls individual downloads, since multiple download records 36 can be processed in each iteration, it may still be presenting extremely bursty traffic to the underlying protocol stack and to the attached network, which may cause a local failure. If this is detectable to the server 12, for example by a return code from a message sending primitive, then the server 12 should defer further work in that scheduling timeslot 34 and reschedule all remaining download requests 36 until the next available timeslot 34.
The preferred implementation of the PDU Scheduler 28 should have a tick granularity for the timer 30 (corresponding to timeslot granularity for the PDU scheduling queue 32) that is considerably smaller than the minimum inter-PDU delay. As long as download requests arrive relatively randomly, distribution of outstanding requests within the scheduler timeslots 34 will be improved, and the chance of server overloads will be reduced.
It is acceptable for the server 12 to service a download at a lower rate than requested, and this may occur during periods of overload, but care must be taken that the inter-PDU delay for a particular download is never less than the client specified time.
Those skilled in the art will recognize that various modifications and changes could be made to the invention without departing from the spirit and scope thereof. It should therefore be understood that the claims are not to be considered as being limited to the precise embodiments of the BLAST protocol and server set forth above, in the absence of specific limitations directed to each embodiment. | This invention relates to a method and protocol to enable a simple, reliable and highly scaleable data transfer facility in a digital data network. A connectionless, unacknowledged data transfer protocol minimizes resource utilization at a data server and is combined with source rate control to reduce congestion in the intervening network. The data transfer server implementing the protocol, operates by defining a circular ordering of individual scheduling timeslots having zero or more download records. The server selects in sequence, at a predetermined rate, the individual scheduling timeslots, and services, responsive to the selected timeslot having at least one download record, each record therein according to parameters in that record. Servicing includes (I) sending, to the destination address, a download message which includes a block of data extracted from the identified data, based on the remaining data information; (ii) updating the remaining data information to reflect the block of data that was sent; and (iii) resheduling, based on the transfer rate and the predetermined rate, the download record into an appropriate one of the scheduling timeslots. | 7 |
BACKGROUND OF THE INVENTION
The invention relates to a fuel injection nozzle for an internal combustion engine. In a known fuel injection nozzle of this kind, the pressure chambers are supplied with fuel either by two pumps or from two independent work chambers, and it is possible to bring the second chamber into play via the slide valve only while the first chamber is supplying fuel. In other words, this is a specialized fuel injection system which is relatively expensive because of the requirement for two work chambers and furthermore has only a limited application.
OBJECT AND SUMMARY OF THE INVENTION
The fuel injection pump according to the invention and having the characteristics set forth herein has the advantage over the prior art that the fuel injection nozzle can be supplied with fuel even with a conventional injection pump, such as a distributor pump, having only one pump work chamber. In addition, there is the possibility of the switching alternatively or switching over from one to the other, as well as of bringing the injection nozzles into play in common. Additional important embodiments of the invention are shown in the drawing and described below.
The invention will be better understood and further objects and advantages thereof will become more apparent from the ensuing detailed description of preferred embodiments taken in conjunction with the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a cross-sectional view of the first exemplary embodiment in simplified form;
FIG. 2 is a cross-sectional detailed view of the exemplary embodiment shown in FIG. 1; and
FIGS. 3, 4 and 5 also show further cross-sectional views of the second exemplary embodiment of this invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
In FIG. 1, a fuel injection nozzle is shown having the conventional structure as follows: nozzle holder 1, intermediate plate 2, nozzle body 3, sleeve nut 4 and nozzle needles 5. The nozzle needles 5 are urged in the closing direction by closing springs 7 via spring supporting plates 6. The chamber 8 which encloses the springs 7 is relieved of pressure via a channel 9. The invention pertains to an injection nozzle having two nozzle needles 5 and, correspondingly, two closing springs 7, but only one spring chamber 8. Between the nozzle needles 5 and the nozzle body 3 there are pressure chambers 11 in the area of the pressure shoulder 10 of the nozzle needle 5. The pressure chambers 11 communicate with inlet channels 12 and 13 in the nozzle holder 1, the channels 12 and 13 being connectable via a slide valve 14 with an inlet line 15, by way of which the fuel, under high pressure, is delivered to the injection nozzle.
In FIG. 1, the upper portion of the nozzle holder 1 has been shown rotated by 90° relative to the lower portion, in order to be able to show one each of the pressure chambers 11 in the nozzle body 3 and the closing spring 7 in section and also to be able to show the inlet channels 12 and 13 in the upper portion. The slide valve 14 is provided with a slide 16, which is displaceable counter to the force of a restoring spring 17 by pressure fluid located in a chamber 18. The particular fluid is controlled in accordance with engine characteristics by means which are not shown (for instance, a magnetic valve) and is delivered to the chamber 18 via a nipple 19. Depending upon the pressure of this particular fluid, the slide 16 is displaced to a greater or lesser extent counter to the spring 17 and thus provides various connections between the inlet line 15 and the inlet channels 12 and 13. In the switching position shown, there is a connection from line 15 to channel 12. The fuel thus flows along an annular groove 20 of the slide 16 inside the bore 21 enclosing the slide 16, from an annular groove 22 of this bore 21 communicating with the inlet line 15 to an annular groove 23 communicating with the inlet channel 12. A relief channel 24 is disposed in the slide 16, which in the illustrated position is arranged to connect the inlet channel 13 with the pressure-relieved chamber 25 that encloses the spring 17. The relief line 9 of the spring chamber 8 also discharges into this chamber 25. The chamber 25 communicates with a leakage line, not shown, by means of a connector nipple 26.
As soon as the slide 16, as a result of increasing pressure in the pressure chamber 18, is displaced toward the right against the force of the spring 17, the annular grooves 22 and 23 communicate via the annular groove 20 with an annular groove 27, from which the inlet channel 13 branches off. After this distance has been covered, i.e., the slide 16 has moved to the right, as viewed in the drawing, the relief channel 24 can no longer communicate with the annular groove 27. This connection is effected in an intermediate position of the slide 16 and the precondition for it is that the annular groove 20 be longer than the distance from the annular groove 23 to the annular groove 27. In this position, both pressure chambers 11 are supplied with fuel, if such a supply is desired and if a pressure step is provided, such as that shown in FIG. 3. In the illustrated example, the slide 16 moves beyond this position until it is displaced against the nipple 26, which here acts as a stop. In this terminal position, the annular groove 20 is separated from the annular groove 23, so that only the connection between annular groove 22 and annular groove 27 remains. The fuel thus moves only into the inlet channel 13. The inlet channel 12 is blocked, and in this position it is relieved of pressure via the relief channel 24 in the slide 16.
In some internal combustion engines, there is only a small space for receiving the fuel injection nozzle, this being a bore of small diameter. When fuel injection nozzles having two parallel nozzle needles are used, it is accordingly necessary to dispose these needles are close as possible to one another, as indicated in FIG. 2. However, when there are parallel closing springs, this minimum distance is determined by the diameter of these springs, which cannot be further reduced as required. In the variant of the first exemplary embodiment shown in FIG. 2, in which the corresponding reference numerals are simply given a prime, the first spring 7' is shifted relative to the other, so that only one lengthened pressure rod 29 of one nozzle needle 5' extends beside the remaining spring 7'. The spring chamber 8' is accordingly embodied in a stepped fashion.
In the second exemplary embodiment shown in FIGS. 3-5, the reference numerals of elements corresponding to those of FIGS. 1 and 2 are given a double prime. As shown in FIG. 3, the two nozzle needles in this exemplary embodiment are disposed coaxially relative to one another, the first nozzle needle 31 being enclosed by a hollow needle 32. The nozzle needle 31 has a pressure chamber 33 disposed between the two needles, and the hollow needle 32 has a pressure chamber 34 disposed between the hollow needle 32 and the nozzle body 3". While the pressure chamber 34 communicates directly with the inlet channel 12", the connection between the inlet channel 13" and the pressure chamber 33 is provided by an annular groove 35 disposed in the nozzle body 3" and by radial bores 36 disposed in the hollow needle 32, which connect the annular groove 35 with the pressure chamber 33. The pressure springs acting upon the nozzle needles 31 and 32 are switched in parallel, as in the first exemplary embodiment. The closing spring 37 of the hollow needle 32 has a substantially larger diameter than does the closing spring 38 of the inner needle 31, because the face of the hollow needle 32 which moves in the opening direction under the impact of the delivered fuel is by its structure necessarily substantially greater in area than that of the inner needle 31. The pressure chambers 33 and 34 are hydraulically completely separated from the inlet channels 12" and 13" respectively. The slide-valve 14" functions in principle and is similar to that shown in the first exemplary embodiment. In contrast thereto, however, the slide 16" is disposed coaxially with the axis of the injection nozzle, because the fuel pressure connection with the fuel inlet line 15" is effected transversely to the nozzle axis. Not only is there the advantage of the small diameter of this exemplary embodiment, but also fewer channels are necessary for preventing leakage, because the chamber 25" enclosing the spring 17" of the slide 16" communicates directly with the spring chamber 8" via a bore 39. In contrast to the first exemplary embodiment, the slide 16", after covering a first stroke distance, strikes against a stop 42 which is subject to the force of a spring 41. Only when there is a further pressure increase (pressure step) in chamber 18" is the force of the spring 41 overcome and the slide 16" now displaced into its terminal position counter to the force of both springs 17" and 41.
In the outset position of the slide 16" shown in FIG. 3, the slide 16" connects the inlet line 15" with the inlet channel 13" via the annular groove 20". As soon as the slide 16" is then displaced downward, counter to the force of the spring 17", a connection is provided between the line 15" and the channel 12" after the distance to the stop 42 has been covered, so that fuel can be injected only via the hollow needle 32. The channel 13" is then separated from the line 15", as shown in FIG. 4. In FIG. 5, the slide 16" is then shown in its terminal position, after the force of the spring 41 has been overcome. In this position, the line 15" communicates with both channels 12" and 13". The connection with channel 13" is effected by way of a bore 43 extending within the slide 16". As a result, it is possible subsequently to open in sequence first one of the channels, then the other in alternation, and finally both at the same time.
The foregoing relates to preferred exemplary embodiments of the invention, it being understood that other embodiments and variants thereof are possible within the spirit and scope of the invention, the latter being defined by the appended claims. | A fuel injection nozzle is proposed having two nozzle needles in which the control of the fuel delivered via an inflow line is effected by means of a slide valve embodied as a 3-way valve, which in a preferred embodiment of the invention is simultaneously embodied as a 3-position valve and permits not only the alternative exertion of the fuel pressure upon one of the nozzle needles but also a common pressure exertion of both nozzle needles. | 5 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of and is a national phase filing of the PCT patent application entitled “Cementitious Board Manufacture” having International Application No. PCT/GB2006/050332, filed Oct. 17, 2006, which claims the benefit of the Great Britain patent application having application no. 0521238.6, filed Oct. 19, 2006, both of which are hereby incorporated by reference in their entirety as if fully set forth herein.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] This invention relates to the manufacture of cementitious board in which a slurry of cementitious material, commonly gypsum plaster, is deposited between two facing lining sheets and formed to a desired width and thickness prior to setting and drying. The process is normally carried out continuously and at high linear speed.
[0004] 2. Description of the Relevant Art
[0005] To manufacture gypsum board, an aqueous slurry of calcined gypsum (calcium sulphate hemihydrate) is continuously spread between upper and lower paper sheets. The product formed is then continuously conveyed on a moving belt until the slurry has set. The strip or sheet is then dried until the excess water in the gypsum board has evaporated. In the production of gypsum wallboard, it is known to add various substances to the slurry to enhance the production process or the board itself. For example, it is usual to lighten the weight of the slurry by incorporating foaming agents to provide a degree of aeration which lowers the density of the final wallboard.
[0006] It is also known to decrease the setting time of the calcined gypsum slurry by incorporating gypsum set accelerators. Freshly ground gypsum (also known as a gypsum set accelerator) has a relatively short shelf life. The loss of acceleration efficiency of conventional accelerator materials is also exacerbated when the accelerator is exposed to heat and/or moisture.
[0007] To combat this loss of efficiency, it is known to coat the accelerator particles with, for example, sugar or a surfactant.
[0008] Accordingly, there is a need for a gypsum set accelerator or method of accelerating the set time of the gypsum slurry which alleviates the aforementioned problems.
BRIEF SUMMARY OF THE INVENTION
[0009] According to the present invention, there is provided a method for accelerating the setting reaction of calcium sulphate hemihydrate and water comprising mixing water and calcium sulphate hemihydrate to product a slurry, adding an accelerator to said mixture, and applying ultrasonic energy to said mixture.
[0010] The ultrasonic energy may be applied for a time of less than 10 seconds.
[0011] The accelerator may be hydrated calcium sulphate.
[0012] The accelerator may be a chemical accelerator.
[0013] The chemical accelerator may be potassium sulphate (K 2 SO 4 ).
[0014] The slurry may be formed within a mixer and deposited via a mixer outlet onto paper so as to form gypsum plasterboard, said paper being located on a conveyor.
[0015] The ultrasonic energy may be applied to the slurry when the slurry is located in the mixer outlet.
[0016] The ultrasonic energy may be applied to the slurry once it is deposited on the paper conveyor.
[0017] The ultrasonic energy may be applied using a radial shaped ultrasonic horn positioned at the exit mouth of the mixer outlet.
[0018] The ultrasonic energy may be applied directly to the slurry in the mixer.
[0019] The ultrasonic energy may be applied directly to the slurry in the mixer via probes inserted into the slurry contained within the mixer.
[0020] The ultrasonic energy may also be applied via the rotor in the mixer.
[0021] Also according to the present invention there is provided apparatus for manufacturing gypsum wall board comprising a mixer for combining calcium sulphate hemihydrate and water, a mixer outlet for depositing the gypsum slurry onto paper mounted onto a conveyor, wherein said mixer outlet comprises means for supplying ultrasonic energy to the slurry as it passes through said mixer outlet.
[0022] Said mixer outlet may comprise a tubular shaped ultrasonic horn.
[0023] Advantageously, the application of ultrasonic energy together with a known accelerator provided a decreased setting time and therefore a more efficient plasterboard manufacturing process. The application of ultrasonic accelerator in to the mixer has also surprisingly alleviated material build up in the mixer. This is caused by the vibration produced by the application of ultrasonic energy to the mixer. In particular, the combination of the use of ultrasonic energy in combination with a known gypsum accelerator has provided surprisingly goods results with the amount of particulate or chemical accelerators needed being reduced.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0024] Embodiments of the invention will now be described with reference to the accompanying drawings in which:
[0025] FIG. 1 is a fragmentary diagrammatical view of a longitudinal section of a gypsum board manufacturing line.
[0026] FIG. 2 is an example of a shape of a mixer outlet according to an embodiment of the present invention.
[0027] FIG. 3 is a diagrammatic view of a mixer outlet in the shape of a radial horn according to a further embodiment of the present invention.
[0028] FIG. 4 is a diagrammatical section of a mixer with ultrasonic probes.
[0029] FIG. 5 is a diagrammatical section of a mixer with an ultrasonic rotor according to a further embodiment of the invention.
DETAILED DESCRIPTION OF THE INVENTION
[0030] Referring to FIG. 1 , a first layer of paper 12 is fed from a roll 14 onto a conveyor or belt 16 . A storage mixer 18 contains a slurry of calcium sulphate hemihydrate and water. This storage mixer 18 is provided with an outlet 20 connected to a conduit 22 . A meter is connected to said conduit 22 for measuring and controlling the amount of stucco fed through the conduit 22 .
[0031] Additives are added to the storage mixer 18 . Such additives may comprise retarders (e.g., proteins, organic acids), visocity modifying agents (e.g., superplasticisers), anti-burning agents, boric acid, water-resisting chemicals (e.g., polysiloxanes, wax emulsions), glass fibers, fire-resistance enhancers (e.g., vermiculite, clays and/or fumed silica), polymeric compounds (e.g., PVA, PVOH) and other conventional additives imparted in known quantities to facilitate manufacturing such as starch.
[0032] The storage mixer 18 is provided with an outlet 20 to deliver its combined contents in the form of slurry onto the paper 12 .
[0033] This slurry mixture is then delivered through an outlet pipe 22 onto the paper 12 provided on the moving belt 16 .
[0034] An additive such as starch is added to the slurry stream 24 in the mixer and a further layer of paper 26 is provided over its upper surface from a roll 28 . The slurry is therefore sandwiched between two sheets of paper or cardboard 12 and 26 . These two sheets become the facing of the resultant gypsum board.
[0035] The thickness of the resultant board is controlled by a forming station 30 , and the board is subsequently prepared by employing appropriate mechanical devices to cut or score, fold, and glue the overlapping edges of the paper cover sheets 12 and 26 . Additional guides maintain board thickness and width as the setting slurry travels on the moving conveyor belt. The board panels are cut and delivered to dryers to dry the plasterboard.
[0036] In the current embodiment of this invention, the conduit 22 may be replaced by a ring shaped radial horn through which the slurry may be fed to the slurry stream 24 and, during transit through the conduit, the ultrasonic energy may be delivered.
[0037] Referring to FIG. 2 , the conduit 22 may be constructed in the form of a metallic ultrasonic radial horn with outer metallic tubing 40 and inner bore 42 . The slurry 24 passes through the conduit 22 where ultrasonic energy is imparted as it forms the slurry stream on the paper 12 .
[0038] Advantageously, the use of ultrasonic energy applied to the gypsum slurry accelerates the setting time of the gypsum by causing accelerated crystallization.
[0039] It is understood that when the amount of ultrasonic energy applied to the gypsum slurry exceeds the natural forces holding together the molecules, cavitation occurs.
[0040] The implosion of the cavitation bubbles produces short lived hot spots within the slurry. The collapse of some of the bubbles within the slurry enable nucleation sites to occur thus allowing accelerated crystallization.
[0041] This has the added advantage of making the slurry outlet nozzle a self cleaning delivery unit due the vibration produced by the ultrasonic energy. The vibrations at the mixer outlet also allow the slurry to be spread evenly across the moving conveyor.
[0042] In one embodiment of this invention, the conduit 22 may be replaced by a wide mouthed tubular ultrasonic horn through which the slurry may be fed to the slurry stream 24 and, during transit through the conduit, the ultrasonic energy may be delivered.
[0043] Referring to FIG. 3 , the conduit 22 may be constructed in the form of a metallic ultrasonic radial horn with tubular outer metallic tubing 50 connected by some means to a conical section 52 , thereby forming a wide mouthed slurry output bore 54 . The slurry 24 passes through the conduit 22 where ultrasonic energy is imparted as it forms the slurry stream on the paper 12 . Also, advantageously, by using a wide mouthed design of ultrasonic horn as the mixer outlet, the slurry stream on the paper 12 may be more uniformly distributed and less reliant on the use of additional mechanical vibration apparatus.
[0044] Referring now to FIG. 4 , a pair of ultrasonic probes 52 , 54 could alternatively be inserted into the mixer chamber 18 itself. The probes 52 and 54 advantageously act as a method for preventing mixer blockage by providing vibration to the slurry mixture.
[0045] Referring to FIG. 5 , the rotor 53 of the mixer is itself provided with ultrasonic energy via a generator 57 . The rotor is essentially a conventional rotor but additionally provided with ultrasonic energy which it can impart to the gypsum slurry mixture fed into the mixer chamber 18 .
[0046] The following example results further illustrate the present invention but should not be construed as limiting its scope.
[0047] With reference to the examples:
The slurry was made using stucco of different water gauges including 70, 80 and 90 wt % of stucco (no additives) to obtain different viscosities. The different slurries with the different water gauges were insonated with an ultrasonic probe (at a fixed frequency of 20 kHz) for different intervals, including 2, 3, 5, 10, 15 and 20 seconds. The set time for each insonation was measured using a Vicat set test. To determine the effect of foam on the insonation, different slurries with different addition levels of foam were tested in the same manner as explained above for the unfoamed slurries. In this case, the water gauges were kept constant and the foam addition level altered. Both sets of examples (using unfoamed and foamed slurries) were repeated using different ultrasonic probes with different power outputs (1 kW and 1.5 kw). The examples were repeated with the use of ultrasound in combination with particulate accelerator, Ground Mineral Nansa (GMN) and a chemical accelerator, potassium sulphate.
EXAMPLE 1
[0054] Prisms were made using 1000 g of stucco at three different water gauges of 70, 80, and 90 wt % of stucco. Ultrasonic energy was applied to the slurry for 3, 5 and 10 seconds using an ultrasonic probe with a power output of 1 kW. A large high-speed blender was used to mix the stucco and water for a dispersion time of 5 seconds. The water used remained at a constant temperature of 40° C. No foam was added to the slurry in this case.
[0000]
TABLE 1
Difference
Average
Water
Initial Set
Final Set
in Set
Average
Compressive
Insonation Time
Gauge
Times
Times
Time
Density
Strength
(seconds)
(wt %)
(minutes)
(minutes)
(minutes)
(kg/m3)
(MPa)
0
70
8.10
9.45
1080
12.7
10
70
4.50
7.00
−2.45
1078
14.6
0
80
8.00
9.20
1004
10.4
3
80
6.56
7.57
−2.03
994
10.9
0
80
8.35
10.10
995
9.9
5
80
6.20
8.20
−2.30
990
10.3
0
80
8.15
9.45
986
9.6
10
80
5.50
7.13
−2.32
969
10.9
0
90
8.00
9.50
913
8.2
3
90
6.57
8.00
−1.50
921
8.6
0
90
8.30
9.30
959
8.0
5
90
6.38
7.40
−2.30
927
9.5
0
90
8.30
10.15
912
8.4
10
90
6.37
8.00
−2.15
917
8.8
EXAMPLE 2
[0055] Tests were carried out to determine the effect of ultrasonic acceleration on foamed slurries. Prisms were made using 1000 g of stucco with a water gauge of 90 wt % of stucco. A foam generator was used to produce the foam to be added to the stucco blend. The foam generator was set to have an airflow rate of 2.5 I/min, foam flow rate of 0.25 l/min, and a foam concentration of 0.3%. To produce the slurry mix, a large blender was used on low speed for a total dispersion time of 10 seconds. The 1 kW ultrasonic probe was used at insonation times of 3, 5 and 10 seconds to accelerate the set of the gypsum slurry.
[0056] The stucco and water was mixed in a large batch mixer for 3 seconds before the foam was added to the blend and mixed for a further 7 seconds to produce samples 1 and 2. In the case of samples 3 and 4, stucco was mixed with water for 3 seconds before the foam was added and mixed for a further 4 seconds.
[0000]
RESULT TABLE 2
Difference
Average
Insonation
Initial Set
Final Set
in Set
Average
Compressive
Time
Times
Times
Time
Density
Strength
(seconds)
(minutes)
(minutes)
(minutes)
(kg/m3)
(MPa)
0
11.00
13.00
828
5.19
3
9.27
10.20
−3.20
812
4.20
0
11.45
13.15
723
2.99
3
10.58
11.50
−2.05
607
2.17
0
8.30
10.30
776
4.62
5
6.15
7.15
−3.15
755
2.35
0
10.15
12.00
781
4.88
5
7.20
8.20
−4.20
715
3.82
0
12.15
13.00
735
3.88
10
8.36
9.30
−4.10
714
2.65
0
10.15
12.00
807
4.71
10
7.16
7.50
−4.50
753
2.72
EXAMPLE 3
[0057] To compare the set times obtained with particulate accelerator as opposed to solely ultrasonic energy, prisms were made to test the effect of ultrasound on particulate accelerator (GMN). In this case, no foam was added and a water gauge of 90 wt % of stucco with a water temperature of 40° C. was used. A large high-speed blender was used to mix the stucco and the GMN with water for a 5 second dispersion time. GMN was hand mixed into dry stucco powder for 30 seconds before making the slurry in the blender.
[0000]
RESULT TABLE 3
Difference
Average
Insonation
Initial Set
Final Set
in Set
Average
Compressive
Time
% GMN
Time
Time
Time
Density
Strength
(seconds)
(wt %)
(minutes)
(minutes)
(min)
(kg/m3)
(MPa)
control
0
0.5
3.00
3.45
905.89
8.33
3
0.5
2.12
3.00
−0.45
852.52
4.23
5
0.5
2.24
3.00
−0.45
815.20
5.65
10
0.5
1.50
2.48
−1.37
829.94
4.66
control
0
0.1
5.30
6.15
904.24
8.63
3
0.1
4.30
5.30
−1.25
880.61
8.55
5
0.1
3.45
4.40
−2.15
876.04
7.32
10
0.1
3.50
4.54
−2.01
892.16
7.37
control
0
0
8.50
11.00
903.85
6.92
10
0
4.30
5.20
−6.20
921.21
11.00
EXAMPLE 4
[0058] Non-foamed slurry was insonated using a higher power probe that could draw 1.5 kW compared with the 1 kW power (that the previous probe was capable of).
[0059] 1000 g of stucco with a water gauge of 90 wt % (water temperature of 40° C.) was again mixed in a high-speed blender for 5 seconds to produce the samples.
[0000]
TABLE 4
Difference in Set
Insonation Time
Initial Set Time
Final Set Time
Times
(seconds)
(minutes)
(minutes)
(minutes)
0
10.30
−0.30
2
7.30
10.00
0
7.45
9.25
−3.05
15
4.30
6.20
0
8.00
9.15
−4.25
20
4.15
5.30
EXAMPLE 5
[0060] Non-foamed samples with two addition levels (0.06 and 0.1 wt %) of potassium sulphate (chemical accelerator) were insonated using a higher powered probe (1.5 kw) for different intervals to determine whether ultrasonic cavitation could be used in conjunction with potassium sulphate to further accelerate the set time of gypsum slurry.
[0000]
TABLE 5
Initial
Final
Difference
Insonation
Potassium
Set
Set
in Set
Compressive
Time
Sulphate
Time
Time
Time
Density
Strength
(seconds)
(wt %)
(minutes)
(minutes)
(minutes)
(kg/m 3 )
(MPa)
0
0
7.56
10.56
−1.41
927.06
8.68
2
0
7.00
9.15
919.40
8.38
0
0.06
7.12
8.12
−1.53
914.61
8.31
2
0.06
4.40
6.59
909.86
8.72
0
0.06
5.47
7.38
−1.39
910.10
8.03
3
0.06
4.06
6.39
908.97
8.18
0
0.06
5.59
8.20
−2.00
910.81
8.42
10
0.06
5.25
6.20
916.53
9.08
0
0.1
6.18
7.56
−1.19
922.73
8.42
2
0.1
5.25
6.37
914.02
8.53
0
0.1
4.58
7.06
−1.56
917.63
8.22
3
0.1
4.58
5.50
921.49
8.67
0
0.1
5.57
7.39
−2.09
902.00
8.32
10
0.1
4.35
5.30
900.25
8.72
[0061] As seen in table 5, the application of ultrasound energy in combination with a chemical accelerator (potassium sulphate) produces a substantial increase in set time. This particular combination of ultrasound energy and chemical accelerator has been found to be more effective in reducing the setting time of the gypsum slurry than either method on its own.
[0062] Table 6 is a list of results obtained from ‘on plant’ trials using ultrasound according to the present invention to accelerate the setting of gypsum.
[0000]
Table Of Results For Plant Trials Using Ultrasound To Accelerate The Setting Of
Gypsum Products
Final
Avg
Difference
Date
Description
Trial
set
final set
(minutes)
Notes
Oct. 05, 2005
Control
1
3.20
3.15
−1.10
Control
3.20
Control
3.20
Control
3.10
Control
3.00
Control
3.20
Oct. 05, 2005
Uls on line radial horn
2
2.50
2.45
circumference only
Uls on line radial horn
2.40
circumference only
Oct. 05, 2005
Control
2a
3.20
3.30
−0.20
Control
3.40
Uls on line radial horn
3.10
3.10
circumference only (Natural
Gypsum)
Oct. 05, 2005
Control
4
3.50
3.42
Control
3.20
Control
3.55
Uls through centre of radial horn
3.00
2.78
−1.04
into skip
Uls through centre of radial horn
2.55
into skip
Uls 90 degree to flow underneath
3.15
3.15
−0.27
into skip
Nov. 05, 2005
Control
5
3.10
2.87
Control
2.50
Control
3.00
Nov. 05, 2005
Control
6
3.50
3.50
0.28
Uls with centre blocked same
4.00
3.78
NB. Too much
direction as flow into skip
foam present
Uls with centre blocked same
3.55
NB. Too much
direction as flow into skip
foam present
Control
3.35
3.45
−1.28
Control
3.55
uls with centre blocked same
3.05
2.58
Half stream
direction as flow into skip
sonicated
uls with centre blocked same
2.30
Full stream
direction as flow into skip
sonicated
uls with centre blocked same
2.50
direction as flow into skip
uls with centre blocked same
2.45
direction as flow into skip
Nov. 05, 2005
Control
7
4.30
4.25
−1.37
Control
4.20
Uls through horn (added water)
4.20
ignore
Too much water
into skip
Uls through horn
3.25
3.28
Uls through horn into skip
3.20
Uls through horn into skip
3.40
Nov. 05, 2005
Control - Normal recipe into skip
8
3.25
3.18
Control - Normal recipe into skip
3.10
Control - Normal recipe into skip
3.20
Control - no GMN or retarder
3.55
3.55
−0.50
Suspect some
GMN still present
Uls under the horn same direction
3.10
3.05
as flow (no GMN or retarder)
Nov. 05, 2005
Uls under the horn same direction
3.00
as flow into skip (no GMN or
retarder)
Control - Flushed out all GMN and
3.40
3.40
−1.13
no retarder
Uls under the horn same direction
2.25
2.28
as flow into skip (no GMN or
retarder)
Uls under the horn same direction
2.30
as flow into skip (no GMN or
retarder)
Control - no GMN but with retarder
3.50
3.50
−0.50
Uls under the horn same direction
3.50
3.00
as flow (no GMN with retarder)
Uls under the horn same direction
2.50
as flow into skip (no GMN but with
retarder)
Nov. 05, 2005
Control - No GMN or retarder
9
3.40
3.67
−1.11
Control - No GMN or retarder
3.10
Control - No GMN or retarder
2.45
Control - No GMN or retarder
4.45
Control - No GMN or retarder
4.45
Control - No GMN or retarder
4.10
Control - No GMN or retarder
4.15
Control - No GMN or retarder
3.25
Uls underneath the horn 90
3.25
2.96
degree to flow (no GMN or
retarder)
Uls underneath the horn 90
2.45
degree to flow (no GMN or
retarder) into skip
Uls underneath the horn 90
3.15
degree to flow (no GMN or
retarder) into skip
Uls underneath the horn 90
3.00
degree to flow (no GMN or
retarder) into skip
Nov. 05, 2005
Control - No GMN or retarder
10
4.10
4.10
−1.33
Uls flat head horn (no GMN or
3.25
3.18
Slurry bouncing off
retarder) 50% of power Amp.
working face.
Uls flat head horn into skip (no
3.10
GMN or retarder) 50% of power
Amp.
[0063] Table 7 is a summary table of results of set time achieved during the plant trials.
[0000]
Difference in
Set Time
Date
Control
Treatment
(minutes)
Oct. 05, 2005
Normal recipe
Ultrasound on-line radial horn,
−0.41
circumference only.
Nov. 05, 2005
Normal recipe
Ultrasound on-line radial horn,
−0.18
circumference only.
Nov. 05, 2005
Normal recipe
Ultrasound through the centre of the
−1.37
radial horn.
Nov. 05, 2005
No
Ultrasound on-line radial horn,
−1.18
accelerator no
circumference only.
retarder.
Nov. 05, 2005
No
Ultrasound on-line radial horn,
−0.50
accelerator
circumference only.
but with
retarder.
Nov. 05, 2005
No
Ultrasound flat head horn, 50% of
−1.33
accelerator no
power.
retarder.
Summary Plot Of Difference in Set Times Achieved with the Use of Ultrasound on Plant Trials
[0000]
Data Regarding Density Reduction with the Use of Ultrasound
[0064] The plots below emphasize the density reduction properties of using ultrasound.
[0065] Comparing all the controls with the ultrasonically treated samples shows that all of them have a lower density than the controls. The treated samples had a corresponding strength with regard to density. The ultrasound did not have a detrimental effect on strength but simply reduced the density. The treated samples present the same proportional change in strength with density as seen from the control samples.
[0066] The density reducing property of ultrasound is another beneficial effect.
[0067] Ultrasound could therefore also be used to aerate the slurry, allowing a reduction in water gauge or foam usage. The reduction in water gauge is of greater economic benefit, since it would mean a reduction on the energy usage. The use of ultrasound would mean the benefit of mechanically aerating the slurry and achieving the same product densities with reduced quantity of water or foam.
[0068] 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 method of accelerating the setting reaction of calcium sulphate hemihydrate and water comprises the steps of mixing water and calcium sulphate hemihydrate to produce a slurry, adding an accelerator to said mixture, and applying ultrasonic energy to said mixture. Application of ultrasound to the plaster slurry accelerates crystallization and thus reduces the setting time. A further benefit is reduced density of the wall boards. | 2 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] The application relates to and claims priority from provisional patent application Ser. No. 60/683,673, titled “CB BLOW-OFF CAP”, filed May 23, 2005, the complete subject matter of which is expressly hereby incorporated herein in its entirety.
BACKGROUND OF THE INVENTION
[0002] This invention relates generally to fire suppression systems used in buildings, restaurants and other commercial kitchens, and more particularly, to blow-off caps used on nozzles within the fire suppression systems.
[0003] Fire suppression systems provide an integral service to commercial kitchens, which use multiple cooking appliances (e.g. chain broilers, deep fryers, broilers, cook tops, and the like) to cook large quantities of food. The cooking appliances are often operated at high temperatures for extended periods of time, creating a large amount of grease and other effluent.
[0004] Fire suppression components are located over the top of the cooking appliances, aimed inside partially enclosed cooking appliances, and are within hoods and ducts associated with the exhaust system. When a hazardous condition is detected, a fire suppression agent is discharged through a nozzle to eliminate the hazardous condition. The fire suppression agent may be, for example, a chemical agent, water, or a combination of the two.
[0005] Due to the large amount of effluent present in the location of the nozzles, clogging of the orifice or orifices through which the fire suppression agent is discharged needs to be prevented so that the system activates correctly when needed. A cap is therefore affixed to the nozzle. The cap is to be blown or pushed off the nozzle, or broken or burst, by the pressure created when fire suppression agent is discharged.
[0006] A silicone rubber cap has been used to cover the end of the nozzle. However, the rubber cap deteriorates due to effluent build up and the high temperature experienced in the exhaust area over broilers and other cooking units. A brass cap held onto the nozzle with a retaining clip has also been used. The retaining clip weakens over time due to, for example, the extreme temperature gradients, allowing the cap to fall off the nozzle. Also, grease accumulates inside the cap and nozzle, effectively freezing the cap onto the nozzle and/or clogging the orifice.
[0007] Therefore, a need exists for a blow-off cap and nozzle assembly capable of withstanding the extreme conditions experienced in commercial kitchen applications, while still allowing the blow-off cap to be pushed off the nozzle during a fire discharge situation. Certain embodiments of the present invention are intended to meet these needs and other objectives that will become apparent from the description and drawings set forth_below.
BRIEF DESCRIPTION OF THE INVENTION
[0008] In one embodiment, a discharge assembly for use with a fire suppression delivery system comprises a nozzle having an outer nozzle surface. The nozzle also has an inlet end configured to receive a fire suppression agent and a discharge end with an orifice therein to dispense the fire suppression agent in a desired manner. A blow-off cap has an open-ended cavity shaped to receive the discharge end of the nozzle and to cover the orifice. The cavity includes an interior cap surface that is located in close proximity to the outer nozzle surface of the nozzle when the blow-off cap is mounted on the discharge end of the nozzle. A receptacle is formed in at least one of the outer nozzle surface of the nozzle and the interior cap surface of the blow-off cap. A retention element is fit within the receptacle and engages the outer nozzle surface and the interior cap surface to provide a predetermined amount of retention resistance to retain the blow-off cap on the nozzle.
[0009] In another embodiment, a blow-off cap for use on a nozzle in a fire suppression system comprises a cover and an O-ring. The nozzle has an outer nozzle surface and inlet and discharge ends. The inlet end is configured to receive a fire suppression agent and the discharge end has an orifice therein to dispense the fire suppression agent in a desired manner. The cover of the blow-off cap comprises a cavity configured to receive the discharge end of the nozzle. The O-ring is fixed within the cavity and is snappingly received over the outer nozzle surface. The O-ring and nozzle provide resistance to retain the blow-off cap on the nozzle until a system pressure builds up sufficient to push the blow-off cap off the nozzle.
[0010] In another embodiment, a fire suppression system comprises a fire suppression delivery system for delivering fire suppression agent. A nozzle has an outer nozzle surface and inlet and discharge ends. The inlet end is configured to receive the fire suppression agent and the discharge end has an orifice therein to dispense the fire suppression agent in a desired manner. A blow-off cap has an open-ended cavity shaped to receive the discharge end of the nozzle and to cover the orifice. The cavity includes an interior cap surface that is located in close proximity to the outer nozzle surface of the nozzle when the blow-off cap is mounted on the discharge end of the nozzle. A receptacle is formed in at least one of the outer nozzle surface of the nozzle and the interior cap surface of the blow-off cap. A retention element is fit within the receptacle and engages the outer nozzle surface and the interior cap surface to provide a predetermined amount of retention resistance to retain the blow-off cap on the nozzle.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 illustrates a fire suppression delivery system and a chain broiler needing overhead broiler protection.
[0012] FIG. 2 illustrates an alternative fire suppression delivery system and an appliance line.
[0013] FIG. 3 illustrates a cross-section of a cover of the blow-off cap in accordance with an embodiment of the present invention.
[0014] FIG. 4 illustrates a view of the blow-off cap with a retention element installed within the cover in accordance with an embodiment of the present invention.
[0015] FIG. 5 illustrates a side view of the nozzle in accordance with an embodiment of the present invention.
[0016] FIG. 6 illustrates the discharge end of the nozzle in accordance with an embodiment of the present invention.
[0017] FIG. 7 illustrates a side view of the cap receiving portion of the nozzle in accordance with an embodiment of the present invention.
[0018] FIG. 8 illustrates a cross-section of the blow-off cap having an interconnected lanyard in accordance with an embodiment of the present invention.
[0019] FIG. 9 illustrates a cross-section of an assembly of the blow-off cap and the nozzle in accordance with an embodiment of the present invention.
[0020] FIG. 10 illustrates the nozzle and the blow-off cap in accordance with an embodiment of the present invention.
[0021] The foregoing summary, as well as the following detailed description of certain embodiments of the present invention, will be better understood when read in conjunction with the appended drawings. It should be understood that the present invention is not limited to the arrangements and instrumentality shown in the attached drawings.
DETAILED DESCRIPTION OF THE INVENTION
[0022] FIG. 1 illustrates a fire suppression delivery system 101 and a chain broiler 100 needing overhead broiler protection. The chain broiler 100 has a chain 102 or other moving belt with a surface 108 which is moved laterally between a top broiler unit 104 and a bottom broiler unit 106 . The surface 108 of the chain 102 may be accessed through an access window 110 on a first end 112 of the chain broiler 100 . The chain 102 moves a food item placed on the surface 108 , such as a hamburger or piece of chicken, from the first end 112 to a second end 114 of the chain broiler 100 , cooking the food item with the top and bottom broiler units 104 and 106 . The food item is removed at the second end 114 through a second access window 116 . The chain broiler 100 has an outer cover 118 which retains heat, protects users from burns, grease spatters and effluent, and provides a barrier between the environment and the components of the chain broiler 100 .
[0023] The chain broiler 100 has an open or substantially open top end 120 to exhaust effluent. The open top end 120 is placed beneath an exhaust hood 122 , which is connected to an exhaust duct within an exhaust system. The exhaust system may provide ventilation for multiple areas within a kitchen, such as additional hoods, chain broilers, upright broilers, ovens and the like.
[0024] The fire suppression delivery system 101 uses a number of interconnected controls, panels, pipes, tanks, bottles, nozzles, blow-off caps, detectors and the like. The fire suppression delivery system 101 may be designed based on the cooking appliances it will be used with. A hazard zone, such as a flat, level and/or rectangular surface including all of the cooking hazards of the protected appliances under the hood or hoods, may be defined when designing the number, flow, location and aiming of the nozzles. Fire suppression is provided to the hazard zone as well as to the hood 122 and other locations within the exhaust system.
[0025] A control unit 124 is located near the hood 122 and provides a control panel 126 to allow operation of the fire suppression delivery system 101 . The control panel 126 may be accessible from the outside of the control unit 124 , or may be behind a door or window. The control panel 126 provides controls to a user, such as an on/off switch 154 and a manual activation switch 156 for manually activating fire suppression. Alternatively, emergency control of the fire suppression delivery system 101 may be provided simply through a manual pull station and a fuel shut off.
[0026] One or more bottles 128 of fire suppression agent may be installed within the control unit 124 , a separate enclosure, or affixed to a wall or other location. A water source 129 may also be supplied to the fire suppression delivery system 101 . The bottle 128 is connected to a pipe 130 , hose or other conduit suitable for carrying the fire suppression agent and able to withstand hot and fluctuating temperatures. An actuator 168 may be connected to the bottle 128 or between the bottle 128 and the pipe 130 . The pipe 130 extends out of the control unit 124 . The pipe 130 is bent in one or more locations, if necessary, such as at elbow 132 , and extends into the hood 122 . The water source 129 may also be connected to the actuator 168 and allowed to flow through pipe 130 , or may be connected to a second actuator and pipe (not shown)
[0027] One or more nozzles 134 , 136 and 138 are interconnected to the pipe 130 and may be positioned uniformly under the hood 122 from the first end 112 of the chain broiler 100 to the second end 114 . The nozzles 134 - 138 are configured to dispense the fire suppression agent through one or more orifices. Each of the nozzles 134 - 138 has a flow rating, angle of coverage, and/or spray pattern, and the type and configuration of nozzles 134 - 138 may vary. For example, both nozzles 134 and 136 may provide a wide angle of coverage while the nozzle 134 has a flow rating of 1 and the nozzle 136 has a flow rating of 2.
[0028] A blow-off cap 140 , 142 and 144 is installed on each of the nozzles 134 , 136 , and 138 , respectively. The blow-off caps 140 - 144 cover the orifice(s) on the nozzles 134 - 138 , each forming a discharge assembly which prevents the nozzles 134 - 138 from clogging with grease and/or other effluent. It should be understood that additional nozzles 134 - 138 and blow-off caps 140 - 144 may be installed to provide protection to other ventilation equipment such as ducts, plenums and filters.
[0029] One or more detectors 146 , 148 and 150 may be connected to the control unit 124 by way of one or more wires 152 . The detectors 146 - 150 detect a condition that needs to be suppressed, such as a fire, excess smoke, or heat beyond an acceptable limit, and report the condition to the control unit 124 . Other methods of detection may be used.
[0030] When the detectors 146 - 150 detect a condition or the manual activation switch 156 is activated, the control unit 124 opens the connection between the bottle 128 and the pipe 130 , such as by energizing the actuator 168 . The fire suppression agent discharges into the pipe 130 at a minimum pressure. The fire suppression agent enters each of the nozzles 134 - 138 and applies a system pressure to each blow-off cap 140 - 144 through the orifice. When the system pressure builds up to a sufficient level, the blow-off cap 140 - 144 is pushed off the nozzle 134 - 138 . The fire suppression agent is discharged out of the orifices of the nozzles 134 - 138 , into the hood 122 and the top end 120 of the chain broiler 100 . By way of example only, the blow-off caps 140 - 144 may be designed to blow off the nozzles 134 - 138 when experiencing system pressure within a range or predetermined limit or limits, such as above a minimum preset pressure. The blow-off caps 140 - 144 stay connected to the respective nozzles 134 - 138 through a lanyard 158 , 160 and 162 , chain or other device after a fire discharge situation.
[0031] One or more fire suppression agents may be used. For example, a fixed amount of wet chemical agent from the bottle 128 may be discharged through the nozzles 134 - 138 . Alternatively, following the discharge of a wet chemical agent, water from the water source 129 may be discharged through the nozzles 134 - 138 , such as in a hybrid system. Alternatively, a clean extinguishing agent may be used instead of a wet chemical agent. A clean extinguishing agent, such as a liquefied gas product, is discharged out of the nozzle 134 - 138 as a liquid and then vaporizes. Optionally, a foam based agent may be used. One or more nozzles may be used to supply the fire suppression agent while the remaining nozzles are used to supply water. Optionally, a dry chemical agent may by applied using a first set of nozzles while a second set of nozzles apply water.
[0032] FIG. 2 illustrates an alternative fire suppression delivery system 250 and an appliance line 252 . The appliance line 252 may be formed of cooking appliances such as a deep fryer 308 , broiler or oven 310 and cook top 312 . The fire suppression delivery system 250 is provided with three tanks, sources or bottles 254 , 256 and 258 of fire suppression agent. As discussed previously, the same or different fire suppression agents may be used. Each of the bottles 254 , 256 and 258 is connected to a pipe 260 , 262 and 264 , respectively. Arrows indicate possible placement and discharge direction for assemblies of nozzles and blow-off caps. Discharge assemblies 266 , 268 , 270 , 272 and 274 are connected to pipe 260 and discharge into exhaust ducts 276 , 278 and 280 . Discharge assemblies 282 , 284 , 286 , 288 and 290 may be connected to pipe 262 and discharge into hoods 292 , 294 and 296 . Discharge assemblies 298 , 300 , 302 , 304 and 306 may be connected to pipe 264 and discharge over the appliance line 252 into the hazard zone. The discharge assemblies may be positioned uniformly or non-uniformly from one end of the appliance line 252 to the other. Each discharge assembly in FIG. 2 includes a nozzle and a blow-off cap.
[0033] FIG. 3 illustrates a cross-section of a cover 170 for a blow-off cap (such as blow-off cap 140 , 142 , 144 ) in accordance with an embodiment of the present invention. The cover 170 is made of metal or other material able to withstand the temperature gradients produced by the chain broiler 100 or appliance line 252 . The cover 170 has a circular wall portion 184 , a closed end portion 186 , a height H 2 and an outer diameter D 2 . A stem 166 extends from the closed end portion 186 and is discussed further below. The circular wall portion 184 and closed end portion 186 have outer and interior cap surfaces 172 and 174 , and form an open-ended cavity 176 for accepting the nozzle 134 ( FIG. 1 ). The cavity 176 has a height H 4 , a first diameter D 3 , a second diameter D 4 , and a closed end 177 .
[0034] The wall portion 184 has a thickness T 1 at a first end 182 and a thickness T 2 at a second end 183 . The wall portion 184 may have a beveled inner edge 188 along the first end 182 . A receptacle 178 with a depth D 1 and a height H 1 is formed in the cavity 176 , starting at a height H 3 from the interior cap surface 174 of the closed end 177 . The receptacle 178 forms a first angle 180 with the interior cap surface 174 and a second angle 181 with a protrusion 164 . First and second angles 180 and 181 may be approximately 90 degrees. The receptacle 178 may be a groove which retains a retention element, such as an O-ring. The depth D 1 and the height H 1 may vary depending upon the size of the retention element or O-ring, operating pressures of the fire suppression delivery system 101 , and the like. It should be understood that the details illustrated and discussed in FIG. 3 are optional, and that a cover 170 may be formed having details different from those shown. Additionally, the diameters, height and width relationships may vary and are not limited to the relationships illustrated. Furthermore, the overall shape of the cover may vary.
[0035] FIG. 4 illustrates a view of the blow-off cap 140 with a retention element installed within the cover 170 in accordance with an embodiment of the present invention. The retention element may constitute an O-ring 190 , which is inserted into the cavity 176 of the cover 170 and securely retained by the receptacle 178 .
[0036] FIG. 5 illustrates a side view of the nozzle 134 in accordance with an embodiment of the present invention. The nozzle 134 has a discharge end 192 and an inlet end 194 . The inlet end 194 is interconnected with the pipe 130 ( FIG. 1 ) such as with a nut 198 , press fitting, or other connector. Towards the discharge end 192 , the nozzle 134 has a cap receiving portion 200 with an outer nozzle surface 216 . The cap receiving portion 200 is inserted into the cavity 176 of the cover 170 . The nozzle 134 is made of metal and has a channel (not shown) formed within for conveying fire suppression agent received from the pipe 130 at the inlet end 194 to an orifice at the discharge end 192 .
[0037] FIG. 6 illustrates the discharge end 192 of the nozzle 134 in accordance with an embodiment of the present invention. The discharge end 192 has one or more orifices 196 in communication with the channel. The suppression agent is released through the orifice 196 .
[0038] FIG. 7 illustrates a side view of the cap receiving portion 200 of the nozzle 134 in accordance with an embodiment of the present invention. The cap receiving portion 200 may be formed of a single piece of material and has a first portion 202 , a receptacle 204 , second and third portions 206 and 210 , and a recess 212 . The first portion 202 has a diameter D 10 and a height H 10 . Referring also to FIG. 3 , the diameter D 10 is substantially equal to or slightly less than the diameter D 4 of the cavity 176 , and the height H 10 is substantially equal to, or slightly less than, the height H 3 .
[0039] The receptacle 204 may be formed adjacent the first portion 202 as a groove having a diameter D 11 and a height H 11 . The receptacle 204 is configured to snappingly receive the O-ring 190 ( FIG. 4 ) when the nozzle 134 is inserted into the cavity 176 of the cover 170 . The second portion 206 is formed adjacent the receptacle 204 , and has a diameter D 12 and a height H 12 . The diameter D 12 is substantially equal to or slightly less than the diameter D 4 of the cavity 176 and the diameter D 10 of the first portion 202 . The diameter D 11 of the receptacle 204 is less than each of the diameters D 10 and D 12 by a depth 208 . The depth 208 is determined by at least one of the size, width or thickness of the O-ring 190 and the amount of pressure required to push the blow-off cap 140 off the nozzle 134 during a fire discharge situation.
[0040] The third portion 210 is formed adjacent the second portion 206 and has a diameter D 13 and a height H 13 . The diameter D 13 is substantially equal to or slightly less than the diameter D 3 . A surface 214 of the third portion 210 is configured to rest against a surface 165 of the protrusion 164 . The recess 212 has a diameter D 14 and a height H 14 which may be varied depending upon the height H 4 of the cavity 176 . Therefore, a total height H 15 of the cap receiving portion 200 is substantially equal to, or slightly greater than, the height H 4 . The recess 212 may be configured to receive an interconnecting member attached to the blow-off cap 140 . As stated previously with FIG. 3 , the details and dimensions of the cap receiving portion 200 of the nozzle 135 illustrated in FIG. 7 are exemplary, and thus may vary and are not limited to the relationships shown.
[0041] FIG. 8 illustrates a cross-section of the blow-off cap 140 having an interconnected lanyard 220 in accordance with an embodiment of the present invention. The lanyard 220 may be formed of a wire 222 , metal mesh, chain, or other material capable of withstanding the extreme heat experienced within the chain broiler 100 and the appliance line 252 . A small loop 236 is formed in a first end 224 of the wire 222 and held by a crimp 226 . The loop 236 is then preened or pressed over the stem 166 . The stem 166 may be formed with a cavity 167 or hole therein. The outer edge of the stem 166 may be rolled outward and down in the direction of arrows 234 , retaining the loop 236 on the stem 166 . Alternatively, a clip (not shown) may be attached to stem 166 and the wire by the crimp 226 . The loop 236 or clip attached to or pressed over the stem 166 may be free to swivel. A second, larger loop 228 is formed in a second end 232 of the wire 222 . The loop 228 interconnects with the nozzle 134 , such as along recess 212 , so that the blow-off cap 140 is retained by the nozzle 134 after the fire suppression delivery system 101 has activated.
[0042] FIG. 9 illustrates a cross-section of a discharge assembly 240 of the blow-off cap 140 and the nozzle 134 in accordance with an embodiment of the present invention. The O-ring 190 is installed in the receptacle 178 in the cavity 176 of the blow-off cap 140 . The blow-off cap 140 is pushed onto the nozzle 134 in the direction of arrow A, inserting the cap receiving portion 200 of the nozzle 134 into the cavity 176 until the O-ring 190 is snappingly received by the receptacle 204 in the nozzle 134 . Thus, the interior cap surface 174 ( FIG. 3 ) is in close communication with the outer nozzle surface 216 ( FIG. 5 ). The O-ring 190 and receptacles 178 and 204 create a seal within the discharge assembly 240 , preventing grease and effluent from building up inside the blow-off cap 140 , freezing the blow-off cap 140 to the nozzle 134 , and/or clogging the orifice 196 ( FIG. 6 ).
[0043] A puff test may be conducted to ensure that the blow-off cap 140 is pushed off the nozzle 134 at the appropriate system or discharge pressure, and may be measured in pressure per square inch (psi). Therefore, the receptacles 178 and 204 and retention element or O-ring 190 provide a predetermined amount of retention resistance to retain the blow-off cap 140 on the nozzle 134 . The discharge pressure range may be based on the normal operation of the fire suppression delivery system 101 . For example, the fire suppression delivery system 101 may be set to operate normally between 45 and 65 psi, that is, the pressure range experienced at the nozzle 134 during a fire discharge situation will be between 45 and 65 psi. The discharge assembly 240 may be designed to separate at, by way of example only, 50 psi. Thus, when the system pressure builds up to the sufficient level of 50 psi, the blow-off cap 140 is pushed off the nozzle 134 .
[0044] The receptacle 204 retains the blow-off cap 140 on the nozzle 134 under the defined system conditions. The discharge pressure needed to push the blow-off cap 140 off the nozzle 134 may be refined by adjusting the size of one or both of the receptacles 178 and 204 . For example, by increasing the depth 208 ( FIG. 7 ) and/or the height H 11 of the receptacle 204 , more pressure is needed to push the blow-off cap 140 off the nozzle 134 . Alternatively, an O-ring 190 or other retention element having a different diameter, thickness or physical properties may be used.
[0045] In addition, a minimum operating limit or range may be established, ensuring that the discharge assembly 240 withstands a predetermined level of vibration. By way of example only, a vibration test using 0.06 inches of displacement at 10 hertz for 8 hours may be conducted during which it is verified that the blow-off cap 140 stays on the nozzle 134 . The discharge assembly 240 is also designed to withstand hot and cold temperature gradients experienced during cooking operations, such as fluctuations between 70 degrees and 200 degrees. Optionally, a single receptacle may be formed in either the blow-off cap 140 or nozzle 134 to retain the O-ring 190 . The receptacle may be adjusted in height, width, and/or diameter to adjust the retention resistance of the discharge assembly.
[0046] FIG. 10 illustrates the nozzle 134 and the blow-off cap 140 in accordance with an embodiment of the present invention. The lanyard 220 is connected to the blow-off cap 140 , and the O-ring 190 is installed in the receptacle 178 inside the cavity 176 . The receptacle 204 on the nozzle 134 accepts the O-ring 190 , and retains the blow-off cap 140 in place. When the fire suppression delivery system 101 is activated, the discharge pressure created at the orifice 196 is great enough to overcome the retention resistance and push the blow-off cap 140 off the nozzle 134 . Fire suppression agent is discharged through the orifice 196 .
[0047] While the invention has been described in terms of various specific embodiments, those skilled in the art will recognize that the invention can be practiced with modification within the spirit and scope of the claims. | A discharge assembly used with a fire suppression delivery system comprises a nozzle having an outer nozzle surface and inlet and discharge ends. The inlet end receives fire suppression agent and the discharge end dispenses fire suppression agent through an orifice. A blow-off cap has an open-ended cavity shaped to receive the discharge end of the nozzle and cover the orifice. The cavity includes an interior cap surface located in close proximity to the outer nozzle surface of the nozzle when the blow-off cap is mounted on the discharge end of the nozzle. A receptacle is formed in at least one of the outer nozzle surface of the nozzle and the interior cap surface of the blow-off cap. A retention element fits within the receptacle and engages the outer nozzle surface and interior cap surface, providing a predetermined amount of retention resistance to retain the blow-off cap on the nozzle. | 8 |
FIELD OF THE INVENTION
[0001] The present invention relates generally to controlling heating, ventilation and air conditioning (HVAC) systems in buildings, and more particularly to maximizing comfort for building occupants.
BACKGROUND OF THE INVENTION
[0002] The comfort of building occupants must be maximized while minimizing energy costs. Most conventional strategies for operating HVAC systems:
[0000] (i) Do not consider the entire system. For instance, the control over multiple rooms in the building is usually decoupled to yield smaller loops over which the control actions are independently solved. This approach fails to consider the full coupling between the subsystems and can lead to poor performance.
(ii) Do not consider thermal and humidity dynamics of the building that predict the evolution of temperature humidity over time.
(iii) Do not consider occupant comfort metrics, such as a predicted mean vote (PMV), or thermal comfort zones during the determination of the operational strategies, and instead employ set-point based strategies. This can lead to increased energy consumption and discomfort for the occupants.
[0003] Most model based optimization approaches for determining the HVAC operational strategies:
[0000] (i) Employ linear programming for the optimization, which can fail to fully model the complete dynamics of the system.
(ii) Do not include constraints on thermal comfort, such as the PMV, and instead rely on set-points for temperature. This can result in increased energy costs.
(iii) When the PMV is used, the model is simplified by linearizing the system equation, which leads to inaccuracies in estimating the true comfort of the occupants. This can result in increased discomfort for the occupants.
[0004] Thus, there is a need to optimize a building HVAC system, and to consider accurate models of occupant comfort and building thermal and humidity dynamics.
SUMMARY OF THE INVENTION
[0005] The embodiments of the invention provide a method for determining an optimal operation of a HVAC system by minimizing energy consumption, while maximizing occupant comfort. The building dynamics are modeled using differential equations that control an evolution of temperatures and humidity in rooms. An energy consumption of the HVAC system is modeled using steady state equations, or differential equations. The occupant comfort is measured using comfort indices such as a predicted mean vote (PMV).
[0006] The PMV determinations involve conditional statements, which result in nonsmooth behavior. Several embodiments for reformulating the conditional statements to computationally tractable forms that are suitable for optimization are provided. A nonlinear program incorporating sparse linear algebra is used to ensure computational efficiency of the method.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] FIG. 1 is floor plan of a building with indoor air conditioners installed in each room and connected with an outdoor unit;
[0008] FIG. 2A is the floor plan with numbered rooms;
[0009] FIG. 2B is a graphical representation of the rooms with nodes representing rooms, and edges representing rooms that share a common wall;
[0010] FIG. 3A is a resistor-capacitor representation of the thermal dynamics of room air;
[0011] FIG. 3B is a resistor-capacitor representation of the thermal dynamics of the wall in the room;
[0012] FIG. 3C is a resistor-capacitor representation of the humidity dynamics of room air;
[0013] FIG. 4 is a flowchart of a method for determining optimal operation of an HVAC system; and
[0014] FIG. 5 is a block diagram of a procedure for minimizing electric power consumption of the outdoor unit according to embodiments of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0015] Building Representation
[0016] FIG. 1 shows a floor plan for a building that can be used by embodiments of our invention. The building includes rooms 10 and doors 12 . Each room is equipped with an indoor air conditioning unit 20 . The indoor units are connected to an outdoor unit 26 . A refrigerant is used for cooling or heating room air flows 22 to the indoor units from the outdoor unit. The refrigerant flows (dashed lines) 24 from the indoor unit to the outdoor unit where the heat is dissipated and the refrigerant is recycled back to the indoor unit 22 .
[0017] FIG. 2A shows a numbering of nine rooms 30 in the building, i.e., 1 to 9. The graph network representation in FIG. 2B based on this numbering. Nodes 40 represent the rooms in the building, and edges 42 represent the rooms that share a wall.
[0018] FIG. 3A provides a resistive capacitive network representation of the building model for thermal and humidity dynamics. The variables used in this figure and other similar figures are described in detail below.
[0019] Input
[0020] As shown in FIG. 4 , input to the optimization method 410 includes the following for a time period:
[0021] Forecast 401 of hourly weather pattern.
[0022] Equipment heat load forecast 402 for each room.
[0023] Prediction 403 of the occupant heat loads.
[0024] Comfort requirements 404 for the occupants.
[0025] Objectives 405 of the optimization.
[0000] The method uses objectives for the optimization 405 and a model 406 .
[0026] The steps of the method as described herein can be performed in a processor connected to a memory, and input and output interfaces as known in the art.
[0027] Output
[0028] Output 420 of the method includes a time profile of control variables in the model which can include: compressor frequency, air flow rate from each room through the conditioner, and the evolution of the temperatures of the room, temperatures of the walls and humidity in the rooms as a result of choice of prescribed control actions. All temperatures are in degrees centigrade.
[0029] Room Dynamics Model
[0030] In the preferred embodiment, the dynamics of the room are modeled as a set of differential equations. A linear resistive capacity circuit modeling the room temperature dynamics is shown in FIG. 3A . The thermal dynamics of the room is modeled as
[0000]
T
z
t
=
T
w
-
T
z
C
z
R
zw
+
m
.
vent
C
p
(
T
oa
-
T
z
)
C
z
+
Q
.
sen
C
z
+
Q
.
sen
,
hvac
C
z
,
(
1
)
[0000] where T z is the temperature of the room in degrees centigrade, T w is the temperature of wall in the room, C z is the heat capacity of the room air in Joules (J) per kilogram (kg), R zw is the resistance for heat transfer between the zone air and the walls of the zone, T oo is the ambient air temperature, C p is the specific heat capacity of air in (J/kg/K), {dot over (m)} vent is the flow rate of ventilation air in (kg/s), {dot over (Q)} sen is a rate of sensible heat generated by equipment, occupants in the room and solar radiation through windows, {dot over (Q)} sen,hvac is a rate of sensible heat transferred to the room air from the indoor air conditioning unit. The dot above the variables indicates the first derivative with respect to time.
[0031] The linear resistive capacity circuit modeling the temperature dynamics of the room wall is shown in FIG. 3B . The thermal dynamics of the wall in the room is modeled as
[0000]
T
w
t
=
T
z
-
T
w
C
w
R
zw
+
T
oa
-
T
w
C
w
R
woa
+
Q
.
ins
C
w
,
(
2
)
[0000] where C w is the heat capacity of the wall in (J/k), R woa is the resistance for heat transfer between the wall and ambient air and {dot over (Q)} inv is the rate of heat transfer from solar radiation to the wall in (W).
[0032] The linear resistive capacity circuit modeling the room humidity dynamics is shown in FIG. 3C . The humidity dynamics of the room air is modeled as
[0000]
h
z
t
=
m
.
vent
(
h
oa
-
h
z
)
ρ
V
a
+
Q
.
lat
ρ
V
a
L
v
+
Q
.
lat
,
hvac
ρ
V
a
L
v
,
(
3
)
[0000] where h z is the specific humidity of zone air in (kg/kg), ρ is the density of air, V a is the volume of air in the room, L is the latent heat of evaporation of water in (J/kg), {dot over (Q)} lat is the rate of latent heat generated by equipment and occupants in the room in (W) and {dot over (Q)} lat,hvac is the rate of latent heat added to the room air by the indoor air conditioning unit.
[0033] Predicted Mean Vote
[0034] In the preferred embodiment, a predicted mean vote (PMV) is used to measure the occupant comfort, see ANSI/ASHRAE Standard 55-2010, Thermal Environmental Conditions for Human Occupancy. The PMV includes parameters that influence comfort: temperature, relative humidity, air velocity, metabolic rate, mean radiant temperature, and clothing insulation. The PMV measures the thermal comfort of the occupants on a scale of −3 to +−3 with: −3: very cold, −2: cold, −1: slightly cool, 0: neutral, +1: slightly warm, +2: warm, +3: hot. The typical range for different building types is prescribed in the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) standard ISO 7730:2005.
[0035] The PMV is determined by the following equations:
[0000]
PMV
=
(
0.303
-
0.036
M
+
0.028
)
[
(
M
-
W
)
-
3.05
×
10
-
3
(
5733
-
6.999
(
M
-
W
)
-
p
a
)
-
0.42
(
(
M
-
W
)
-
58.15
)
-
1.7
×
10
-
5
M
(
5867
-
p
a
)
-
0.0014
M
(
34
-
T
z
)
-
3.96
×
10
-
8
f
cl
(
(
T
cl
+
273.15
)
4
-
(
T
_
r
+
273.15
)
4
)
-
f
cl
h
c
(
T
cl
-
T
z
)
]
,
(
4
)
T
cl
=
35.7
-
0.028
(
M
-
W
)
-
3.96
×
10
-
8
I
cl
f
cl
(
(
T
cl
+
273.15
)
4
-
(
T
_
r
+
273.15
)
4
)
+
I
cl
f
cl
h
c
(
T
cl
-
T
z
)
,
(
5
)
h
c
=
{
2.38
T
cl
-
T
z
0.25
,
if
2.38
T
cl
-
T
z
0.25
>
12.1
v
ar
12.1
v
ar
,
if
2.38
T
cl
-
T
z
0.25
<
12.1
v
ar
,
(
6
)
f
cl
=
{
1.00
+
1.29
I
cl
,
if
I
cl
≤
0.078
1.05
+
0.645
I
cl
,
if
I
cl
>
0.078
,
(
7
)
p
a
=
h
z
0.622
+
h
z
p
atm
,
(
8
)
[0000] where T z is the temperature of the room, h z is the absolute specific humidity in the room, M is the metabolic rate in (W/m 2 ), W is the effective mechanical power in (W/m 2 ), I cl is the clothing insulation in (m 2 k/W), f cl is the clothing area factor, T r is the mean radiant temperature, v ar is the relative air velocity in the room in (m/s), h c is the convective heat transfer coefficient in (W/m 2 /K), p a is the water vapor partial pressure in atmospheres (atm), T cl is the clothing surface temperature, and p atm is the atmospheric pressure in (atm).
[0036] In the PMV model equations, M, W, I cl , f cl are parameters that are specified by the type of activity, e.g., sedentary office work, vigorous workout, that occurs in the room and clothing insulation material that is worn by the occupants in the room. These are not decision variables in the optimization problem. Although Eq. (7) has conditional statement, the value of f cl can be determined a priori for the entire period over which the optimization is performed.
[0037] However, Eq. (6) involves conditional statements involving the decision variables in the optimization problem T z , T cl . One approach to handle this is to add binary variables to the optimization problem and express the conditional statement as
[0000] zε{ 0,1}
[0000] 2.38| T cl −T z | 0.25 ≧(12.1√{square root over ( v ar )}) z
[0000] h c =(2.38| T cl −T z | 0.25 ) z+ 12.1√{square root over ( v ar )}(1− z ). (9)
[0038] If z=1 in Eq. (9), then the first condition in Eq. (6) is enforced and consequently, h c =2.38|T cl −T z | 0.25 . If z=0, then the second conditional in Eq. (6) is enforced and consequently, h c =12.1√{square root over (v ar )}. With this modification, the optimization problem using PMV indices and Eq. (9) will fall in the class of mixed integer nonlinear programs (MINLPs), which are typically computationally complex.
[0039] To address the computational intractability of binary variable based modeling, while still retaining the original PMV formulation, we pose the conditional statement as
[0000] h c =max(2.38| T cl −T z | 0.25 ,12.1√{square root over ( v ar )}). (10)
[0040] This expresses the conditional statement in Eq. (6) but does not allow continuous optimization because Eq. (10) is not smooth. To address this concern, we first consider the following exact reformulation:
[0000]
h
c
=
1
2
(
2.38
T
cl
-
T
z
0.25
+
12.1
v
ar
+
(
2.38
T
cl
-
T
z
0.25
-
12.1
v
ar
)
2
)
.
(
11
)
[0041] It can be verified in Eq. (11) that if the first conditional in Eq. (6) holds, then h c =2.38|T cl −T z | 0.25 . On the other hand, if the second conditional in Eq. (6) holds, then h c =12.1√{square root over (v ar )}. Eq. (11) is differentiable everywhere except at 2.38|T cl −T z | 0.25 =12.1√{square root over (v ar )} because the square root function is not differentiable at 0. This point of non-differentiability is problematic for continuous optimization. To address this concern, the smoothing procedure is applied to Eq. (11) as
[0000]
h
c
=
1
2
(
2.38
T
cl
-
T
z
0.25
+
12.1
v
ar
+
(
2.38
T
cl
-
T
z
0.25
-
12.1
v
ar
)
2
+
τ
2
)
,
(
12
)
[0000] where τ>0 is the smoothing parameter. For all τ>0. Eq. (12) is differentiable everywhere and the continuous optimization algorithms can be readily applied. Because the smoothing parameter τ>0 has to be driven to zero to recover Eq. (6), the method solves a sequence of optimization problem where the value of the smoothing parameter is monotonically decreased. This provides an accurate method for handling the nonsmooth conditional in Eq. (6) and uses continuous optimization algorithms, which are computationally efficient.
[0042] A third approach handles the nonsmooth conditionals in Eq. (10) by writing the max operator as
[0000]
z
=
arg
min
0
≤
y
≤
1
(
-
2.38
T
cl
-
T
z
⌉
0.25
+
12.1
v
ar
)
y
h
c
=
(
2.38
T
cl
-
T
z
0.25
)
z
+
12.1
v
ar
(
1
-
z
)
.
(
13
)
[0043] In Eq. (13), if the first conditional of Eq. (6) is satisfied, then
[0000] z= 1 and h c =2.38| T cl −T z | 0.25
[0000] holds. If the second conditional in Eq. (6) is satisfied, then
[0000] z= 0 and h c =12.1√{square root over ( v ar )},
[0044] This formulation is still not convenient for optimization. Therefore, we replace the minimization in Eq. (13) with the first order stationary conditions as
[0000] −2.38| T cl −T z | 0.25 +12.1√{square root over ( v ar )}−λ+ v= 0
[0000] λ≧0⊥ z≧ 0
[0000] v≧ 0⊥ z≦ 1
[0000] h c =(2.38| T cl −T z | 0.25 ) z+ 12.1√{square root over ( v ar )}(1− z ). (14)
[0045] In Eq. (14), λ≧0⊥z≧0 is a complementarity constraint equivalent to λ, z≧0, λz=0, In other words, λ=0 or z=0. Similarly, the other complementarity condition v≧0⊥z≦1 implies that v=0 or z=1. When these two conditions are taken together it can be seen that λ, v>0 cannot occur since the complementarity conditions will imply that z=0 and z=1. If the first conditional in Eq. (6) holds, then v=12.1√{square root over (v ar )}−2.38|T cl −T z | 0.25 and λ=0, which implies that z=1 and h c =2.38|T cl −T z | 0.25 holds. The case of the second conditional in Eq. (6) holding can be similarly verified.
[0046] Complementarity conditions are difficult to handle within optimization problems. A conventional approach relaxes the conditional statements
[0000] −2.38| T cl −T z | 0.25 +12.1√{square root over ( v ar )}−λ+ v= 0
[0000] λ, z≧ 0,λ z≦τ
[0000] v≧ 0, z≦ 1, v (1− z )≦τ
[0000] h c =(2.38| T cl −T z | 0.25 ) z+ 12.1√{square root over ( v ar )}(1− z ) (15)
[0000] where τ>0 is a relaxation parameter. For all τ>0, Eq. (15) provides a strictly feasible interior to the optimization problems and continuous optimization can be readily applied. Because the smoothing parameter τ>0 has to be driven to zero to recover Eq. (6), the method solves a sequence of optimization problem where the value of the smoothing parameter is monotonically decreased. This provides an accurate method for handling the nonsmooth conditional in Eq. (6) and uses continuous optimization, which is computationally efficient.
[0047] A fourth approach to handle the conditionals in Eq. (6) is to simplify the equations. Typically, the temperature difference between the zone air and clothing in the room |T z −T cl | is less than 5 degrees C. Further, in air conditioned rooms, the relative velocity of the air v ar is typically 0.1 m/s. For these conditions, it can be assumed that the second conditional is satisfied and consequently, we simplify the conditionals in Eq. (6) as
[0000] h c =12.1√{square root over ( v ar )}. (16)
[0048] Building Dynamics and Occupant Comfort Model
[0049] In the preferred embodiment, the dynamical model for a building includes N: rooms and N, walls represented as
[0000]
T
z
,
i
t
=
∑
j
:
j
~
i
T
w
,
j
-
T
z
,
i
C
z
,
i
R
zw
,
ij
+
m
.
vent
,
i
C
p
(
T
oa
-
T
z
,
i
)
C
z
,
i
+
Q
.
sen
,
i
C
z
,
i
+
Q
.
sen
,
hvac
,
i
C
z
,
i
∀
i
=
1
,
…
,
N
z
,
(
17
)
[0000] where the differential variables the subscript i denotes a quantity associated with a room, subscript j denotes a quantity associated with a wall, subscript ij denotes a quantity associated with room i and wall j and notation j:i˜j denotes the set of (i,j) that such that room i has wall j. In the above, T z,i represent the air temperature in room i, T w,j represents the temperature of wall j, {dot over (Q)} sen,i represents the rate of sensible heat generation from equipment, occupants and solar radiation through windows, {dot over (Q)} sen,hvac represent the rate of sensible heating delivered by the air conditioner in room i, {dot over (m)} vent,i is the ventilation air flow rate from room i, C z,i is the heat capacity of air in room i and R zw,ij is the resistance for heat transfer between air in room i and wall j.
[0050] The thermal dynamics of the wall in the building are represented as
[0000]
T
w
,
j
t
=
∑
i
:
j
~
i
T
z
,
i
-
T
w
,
j
C
w
,
j
R
zw
,
ij
+
T
oa
-
T
w
,
j
C
w
,
j
R
woa
,
j
+
Q
.
ins
,
j
C
w
,
j
∀
j
=
1
,
…
,
N
w
,
(
18
)
[0000] where C w,j represents the heat capacity of wall j, R woa,j represents the resistance for heat transfer between the wall j and the outside air, {dot over (Q)}inv,i is the rate of heat gain on wall j from solar radiation, and notation i:i˜j denotes the set of (i,j) that such that room i has wall j.
[0051] The humidity dynamics of the rooms in the building are represented as
[0000]
T
z
,
i
t
=
m
.
vent
,
i
(
h
oa
-
h
z
,
i
)
ρ
V
a
,
i
+
Q
.
lat
,
i
ρ
V
a
,
i
L
v
+
Q
.
lat
,
hvac
,
i
ρ
V
a
,
i
L
v
∀
i
=
1
,
…
,
N
z
,
(
19
)
[0000] where h z,i is the humidity of the air in room i, V a,i is the volume of air in room i, {dot over (Q)} lat,i is the rate of heat generated by equipment, occupants in room i, and {dot over (Q)} lat,hvac,i is the rate of latent heat delivered by the air conditioner in room i.
[0052] The occupant comfort model for all rooms in the building is represented as
[0000]
PMV
i
=
(
0.303
-
0.036
M
i
+
0.028
)
[
(
M
i
-
W
i
)
-
3.05
×
10
-
3
(
5733
-
6.999
(
M
i
-
W
i
)
-
p
a
,
i
)
-
0.42
(
(
M
i
-
W
i
)
-
58.15
)
-
1.7
×
10
-
5
M
i
(
5867
-
p
a
,
i
)
-
0.0014
M
i
(
34
-
T
z
,
i
)
-
3.96
×
10
-
8
f
cl
,
i
(
(
T
cl
,
i
+
273.15
)
4
-
(
T
_
r
,
i
+
273.15
)
4
)
-
f
cl
,
i
h
c
,
i
(
T
cl
,
i
-
T
z
,
i
)
]
(
20
)
∀
i
=
1
,
…
,
N
z
,
T
cl
,
i
=
35.7
-
0028
(
M
i
-
W
i
)
-
3.96
×
10
-
8
I
cl
,
i
f
cl
,
i
(
(
T
cl
,
i
+
273.15
)
4
-
(
T
_
r
,
i
+
273.15
)
4
)
+
I
cl
,
i
f
cl
,
i
h
c
,
i
(
T
cl
,
i
-
T
z
,
i
)
∀
i
=
1
,
…
,
N
z
,
(
21
)
h
c
,
i
=
{
2.38
T
cl
,
i
-
T
z
,
i
0.25
,
if
2.38
T
cl
,
i
-
T
z
,
i
0.25
>
12.1
v
ar
,
i
12.1
v
ar
,
i
,
if
2.38
T
cl
,
i
-
T
z
,
i
0.25
<
12.1
v
ar
,
i
,
(
22
)
f
cl
,
i
=
{
1.00
+
1.29
I
cl
,
i
,
if
I
cl
,
i
≤
0.078
1.05
+
0.645
I
cl
,
i
,
if
I
cl
,
i
>
0.078
∀
i
=
1
,
…
,
N
z
,
(
23
)
p
a
,
i
=
h
z
,
i
0.622
+
h
z
,
i
p
atm
∀
i
=
1
,
…
,
N
z
,
(
24
)
[0000] where for room i, PMV i is the predicted mean vote index for occupants in the room, M i is the metabolic rate in (W/m 2 ) for occupants in the room, W i is the effective mechanical power in (W/m 2 ) in the room, I cl,i is the clothing insulation in (m 2 K/W) in the room, f cl,i is the clothing area factor in the room, T r,i is the mean radiant temperature in the room, v ar,i is the relative air velocity in the room in (m/s), h c,i is the convective heat transfer coefficient in (W/m 2 /K), p a,i is the water vapor partial pressure in (atm) in the room, T cl,i is the clothing surface temperature in the room.
[0053] HVAC Outdoor and Indoor Unit
[0054] In the preferred embodiment, the outdoor and indoor units are modeled as
[0000]
P
hvac
=
a
0
+
a
1
*
T
oa
+
a
2
*
Cf
Q
.
all
,
hvac
=
b
0
+
b
1
*
T
oa
+
b
2
*
C
f
X
cond
=
Δ
X
Δ
H
Q
.
all
,
hvac
Δ
X
=
∑
i
=
1
N
z
m
.
hvac
,
i
h
z
,
i
-
∑
i
=
1
N
z
m
.
hvac
,
i
h
out
∑
i
=
1
N
z
m
.
hvac
,
i
RH
out
=
h
out
0.622
+
h
out
Δ
H
=
∑
i
=
1
N
z
m
.
hvac
,
i
H
z
,
i
-
∑
i
=
1
N
z
m
.
hvac
,
i
H
z
,
out
H
z
,
i
=
C
p
T
z
,
i
+
h
z
,
i
(
C
pw
T
z
,
i
+
L
v
)
H
z
,
out
=
C
p
T
z
,
i
+
h
z
,
out
(
C
pw
T
out
+
L
v
)
T
out
=
(
1
-
BPF
)
*
T
cond
+
∑
i
=
1
N
z
m
.
hvac
,
i
T
z
,
i
∑
i
=
1
N
z
m
.
hvac
,
i
Q
.
sen
,
hvac
,
i
=
m
.
hvac
,
i
C
p
T
out
∀
i
=
1
,
…
,
N
z
Q
.
lat
,
hvac
,
i
=
m
.
hvac
,
i
h
out
(
C
p
T
out
+
L
v
)
∀
i
=
1
,
…
,
N
z
,
(
25
)
[0000] where, P hvac is the amount of electric power consumed by the HVAC outdoor unit, {dot over (Q)} all,hvac is the total heating delivered by the HVAC unit, Cf is the compressor frequency of the HVAC unit, a 0 , a 1 , a 2 , b 0 , b 1 , b 2 are constants, X cond is the amount of condensation in the outdoor unit, ΔX is the difference in specific humidity between the inlet and outlet of the outdoor unit, {dot over (m)} hvac,i is the mass flow rate of air from the room air conditioners, h out is the specific humidity of air at outlet of outdoor unit, RH out is the relative humidity of air at outlet of outdoor unit, ΔH is the difference in specific enthalpy between the inlet and outlet of the outdoor unit, H z,i is the specific enthalpy of the return air from the air conditioner in room i, H out is the specific enthalpy of the air supplied by the outdoor unit to the rooms, BPF is the bypass factor of the outdoor unit, T cond is the condensation temperature at the outdoor unit.
[0055] Typically, RH out is selected to 95%, BPF is selected to 0.2 and T cond is selected to 5 deg C.
[0056] The model in Eq. (25) applies for a single outdoor unit, and can be extended to the case of multiple outdoor units.
[0057] Comfort Optimization Formulation
[0058] In the preferred embodiment, the optimization minimizes the electric power consumption of the outdoor unit as,
[0000]
min
∫
0
T
P
hvac
t
(
26
)
Eq
.
(
17
)
-
(
19
)
,
Eq
.
(
20
)
-
(
21
)
,
(
23
)
,
(
24
)
,
(
25
)
s
.
t
.
h
c
,
i
=
1
2
(
2.38
T
cl
,
i
-
T
z
,
i
0.25
+
12.1
v
ar
,
i
+
(
2.38
T
cl
,
i
-
T
z
,
i
0.25
-
12.1
v
ar
,
i
)
2
+
τ
2
)
∀
i
=
1
,
…
,
N
z
such
that
}
∀
t
∈
[
0
,
T
]
Initial
condition
for
room
temperatu
res
,
humidity
and
wall
temperatu
res
Bounds
on
PMV
i
∀
i
=
1
,
…
,
N
z
Bounds
on
Cf
,
m
.
hvac
,
i
Physical
bounds
on
variabl
es
}
∀
t
∈
[
0
,
T
]
.
[0059] In Eq. (26), a smoothing formulation is used to model the conditional statements in the PMV calculation. The comfort requirement is formulated as upper and lower limits on the PMV for each room. The values of +0.5 and −0.5 are typically used when the building is occupied. The compressor frequency is limited to be within 10 Hz˜80 Hz, and the mass flow rates are also limited based on the capacity of the fans in the individual air conditioning units. In addition, limits such as non-negativity of temperatures, humidity and other quantities from physical considerations are included in the optimization formulation.
[0060] There are a number of parameters whose values for the period of the optimization are provided. These parameters are:
(Q ins,1 , . . . , Q ins,N w , T oa , h oa , M 1 , W 1 , I cl,1 , v ar,1 , {dot over (Q)} sen,occ,1 , {dot over (Q)} lat,occ,1 , . . . , M N z , W N z , I cl,N z , V ar,N z , {dot over (Q)} sen,occ,N z , {dot over (Q)} lat,occ,N z ).
[0062] As described above, the minimization problem in Eq. (26), based on smoothing formulation, is well behaved for τ>0, but the smoothing parameter has to be decreased to 0 to recover a solution to the original problem. The procedure for solving this problem is shown in FIG. 5 .
[0063] For simplicity of this description, the building dynamics model is represented as
[0000]
x
t
=
f
diff
(
x
(
t
)
,
y
(
t
)
,
u
(
t
)
,
(
t
)
)
f
a
lg
(
x
(
t
)
,
y
(
t
)
,
u
(
t
)
,
(
t
)
)
=
0
}
∀
t
∈
[
0
,
T
]
(
x
(
0
)
,
y
(
0
)
)
=
(
x
^
,
y
^
)
,
(
27
)
[0000] where x the set of differential variables corresponds to
(T z,1 , h z,1 , . . . , T z,N z , h z,N z , T w,1 , . . . , T w,N w ), y
the set of algebraic variables corresponds to
(PMV 1 , T cl,1 , T r,1 , h c,1 , p a,1 , {dot over (Q)} sen,hvac,1 , {dot over (Q)} lat,hvac,1 , . . . , PMV 1 , T cl,N z , T r,N z , h c,N z , p a,N z , {dot over (Q)} sen,hvac,N z , {dot over (Q)} lac,hvac,N z ),
u the set of control variables corresponds to
(Cf, {dot over (m)} hvac,1 , . . . , {dot over (m)} hvac,N z ),
and d the set of time dependent parameters
(Q ins,1 , . . . , Q ins,N w , T oa , h oa , M 1 , W 1 , I cl,1 , v ar,1 , . . . , M N z , W N z , I cl,N z , v).
[0068] The differential equations correspond to Equations (17)-(19). The algebraic equations correspond to Equations (20)-(21), (23)-(25) and the smoothing formulation (26). With this representation, the optimization problem in Eq. (26) can be recast as
[0000]
min
∫
0
T
c
(
x
,
y
,
u
)
t
(
28
)
s
.
t
.
x
t
=
f
diff
(
x
(
t
)
,
y
(
t
)
,
u
(
t
)
,
(
t
)
)
f
a
1
g
(
x
(
t
)
,
y
(
t
)
,
u
(
t
)
,
(
t
)
)
=
0
}
∀
t
∈
[
0
,
T
]
(
x
(
0
)
,
y
(
0
)
)
=
(
x
^
,
y
^
)
x
_
(
t
)
≤
x
(
t
)
≤
x
_
(
t
)
y
_
(
t
)
≤
y
(
t
)
≤
y
_
(
t
)
u
_
(
t
)
≤
u
(
t
)
≤
u
_
(
t
)
}
∀
t
∈
[
0
,
T
]
,
[0000] where x , x are lower and upper limits on differential variables, y , y are lower and upper limits on algebraic variables and u , ū Tare lower and upper limits on the controls.
[0069] The limits are assumed to be function of time because different bounds can be specified based on the occupancy conditions. The optimization problem in Eq. (28) is an instance of optimal control problem. These problems are generally solved by discretizing the differential and algebraic equations, which are now imposed at a finite set of time instances instead of all time instants in [0, T].
[0070] Discretization schemes, such as the explicit Euler, implicit Euler, Runge-Kutta methods, or collocation schemes can be used. With such a discretization, the problem in Eq. (28) is reduced to a nonlinear program with finite number of variables and constraints.
[0071] In the preferred embodiment, the optimal control problem is Eq. (28) is discretized using an implicit Euler scheme as
[0000]
min
Δ
t
∑
k
=
1
N
T
c
(
x
k
,
y
k
,
u
k
)
s
.
t
.
x
k
-
x
k
-
1
Δ
t
=
f
diff
(
x
k
,
y
k
,
u
k
,
d
k
)
∀
k
=
1
,
…
,
N
T
0
=
f
a
1
g
(
x
k
,
y
k
,
u
k
,
d
k
)
∀
k
=
1
,
…
,
N
T
(
x
0
,
y
0
)
=
(
x
^
,
y
^
)
x
_
k
≤
x
k
≤
x
_
k
y
_
k
≤
y
k
≤
y
_
k
u
_
k
≤
u
k
≤
u
_
k
}
∀
k
=
1
,
…
,
N
T
,
(
29
)
[0000] where Δt is the time step of the discretization and N T =T/Δt are the number of discretization steps in the optimization. The optimization problem in Eq. (29) is very sparse and appropriate use of spare linear algebra can reduce the computational complexity.
[0072] In the preferred embodiment, the optimization problem in (29) is solved using nonlinear programming algorithms that use sparse linear algebra techniques.
[0073] In another embodiment the conditional equations in PMV calculation is formulated using complementarity constraints
[0000]
min
∫
0
T
P
hvac
t
Eq
.
(
17
)
-
(
19
)
,
Eq
.
(
20
)
-
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[0076] Although the invention has been described by way of examples of preferred embodiments, it is to be understood that various other adaptations and modifications can be made within the spirit and scope of the invention. Therefore, it is the object of the appended claims to cover all such variations and modifications as come within the true spirit and scope of the invention. | A heating, ventilation and air-conditioning (HVAC) system for a building is optimized while maximizing a comfort of occupants and minimizing energy consumption. The building is modeled as a network of nodes and edges, wherein the nodes represent rooms, and the edges represent walls. Dynamics of temperatures and humidity in the rooms and the temperature of the walls and the building are modeled using differential equations and the network. The comfort of the occupants is modeled by a predicted mean vote (PMV). The minimizing is formulated as an optimal control problem, which is discretized using an integration technique to obtain a finite dimensional optimization problem. Then, the finite dimensional optimization problem is solved using sparse linear algebra until convergence. | 5 |
CROSS-REFERENCE TO RELATED UNITED STATES APPLICATIONS
This application is a continuation patent application of our commonly assigned U.S. application Ser. No. 801,421, filed May 27, 1977, entitled "DISPENSER DEVICE WITH VALVE PISTON PUMP" now abandoned, which, in turn, is a continuation-in-part application of commonly assigned, U.S. application Ser. No. 704,939, filed July 13, 1976, and entitled "FOUNTAIN TOOTHBRUSH HAVING BRISTOL CARRIER EASILY PRODUCIBLE BY INJECTION MOLDING", now U.S. Pat. No. 4,068,974, the disclosure of which is incorporated herein by reference.
BACKGROUND OF THE INVENTION
The present invention relates to a new and improved construction of dispenser device of the type comprising a reservoir for a fluent or flowable filled material i.e. a material which is to be dispensed as well as containing a piston pump equipped with a valve arrangement.
Dispenser devices of this type are known to the art in numerous constructional embodiments. They are typically quite complicated in construction and accordingly expensive. Furthermore, they simultaneously markedly inhibit the free construction or design of the apparatus with which such dispenser devices are employed. Thus, it is for instance difficult to construct the reservoir as a cartridge, since for the purpose of connecting the same with the pump there is required a detachable conduit connection. Moreover, the valve arrangement of the state-of-the-art dispenser devices employ automatically activated or even better stated pressure-activated valves, since the positive actuation of the valves requires a complicated valve mechanism which cannot readily be employed for spatial, cost or also functional reasons.
SUMMARY OF THE INVENTION
Hence, it is a primary object of the present invention to provide a new and improved construction of dispenser device which is not associated with the aforementioned drawbacks and limitations of the prior art proposals.
Another significant object of the present invention aims at the provision of a new and improved construction of dispenser device which aims at minimizing the problems associated with the prior art dispenser devices.
Yet a further important object of the present invention is to devise a dispenser device with is relatively simple in construction and design, economical to manufacture, easy to use, not readily subject to malfunction or breakdown, and provides for a positive dispensing action of a fluent material which is to be dispensed.
Now in order to implement these and still further objects of the invention, which will become more readily apparent as the description proceeds, the dispenser device of this development is manifested by the features that the valve arrangement is coaxially disposed with respect to the piston pump which comprises a piston and cylinder arrangement and such valve arrangement has parts connected with the piston as well as parts connected with the cylinder.
With such construction the fabrication of the dispenser devices is particularly simple, since the aforementioned parts of the valve arrangement can be already formed by appropriate construction of the pump parts or components.
Furthermore, the relative movement of the pump parts can be designed such that they can be accomplished practically without any additional complications concerning the positive valve actuation. In addition to the functional reliability which is obtained there is also increased the dosing accuracy and the dispensing action can be rendered substantially independent of the viscosity of the filled material. Furthermore, the reservoir can be readily constructed as a cartridge, since with the previously discussed construction the piston pump and the pump cylinder can form a detachable conduit connection which is situated between the inlet and the outlet of the valve arrangement. This allows installing the cartridge in the handle of the related device and to use such as the actual actuation element both for the pump as well as also for the valve arrangement.
The foregoing design provides a dispenser device which is constructed exceedingly simply, but however, exhibits maximum functional integrity or reliability, and this is so even to the extent that there is prevented in any event any undesired flowing out of the material to be dispensed, but the dispensing thereof however is insured in a reliable manner and with the desired dosage. In particular, the one pump part or component can be equipped with a valve body which can be displaced against spring force. At the end of the pumping stroke this valve body closes off an opening connecting the cylinder chamber or space with the reservoir and again frees such opening during the return stroke of the pump, so that even relatively viscous filled material can easily be delivered into the cylinder compartment. The relevant pump part or component which is equipped with the valve body furthermore can support the one part or component of the outlet valve, for instance, the seat of such outlet valve, against which there sealingly comes to bear an associated valve head during the return stroke of the piston. During the forward stroke of the relevant pump part the valve head is lifted from its seat by the valve body and the outlet from the cylinder compartment is completely freed.
The fields of application of such dispensing device are numerous. In order to more fully explain the different details thereof there will be considered hereinafter, only by way of illustration and not limitation, a toothbrush equipped with the previously described dispenser device of the invention and an appropriately constructed spray can.
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:
FIG. 1 is a longitudinal sectional view of a preferred embodiment of fountain toothbrush equipped with a bristle carrier having a handle and a replaceable cartridge not integral therewith and serving as a reservoir;
FIG. 2 is a cross-sectional view through the cartridge and the guide sleeve surrounding it shown in FIG. 1, taken substantially along the line II--II thereof;
FIG. 3 is a perspective view of the cartridge shown in FIG. 1;
FIG. 4 is an enlarged longitudinal sectional view of the zone of the toothbrush in which the bristle carrier and the cartridge engage one another, wherein the cartridge is in a position in which it protrudes from the open end of the handle part of the bristle carrier;
FIG. 5 illustrates a similar longitudinal sectional view as shown in FIG. 4, but with the cartridge urged into the handle part of the bristle carrier;
FIG. 6 is a perspective partial view of another exemplary embodiment of the conduit member provided in the bristle carrier;
FIG. 7 is a longitudinal sectional view of a part of the piston having inserted therein a part of the embodiment of a conduit element as shown in FIG. 6;
FIG. 8 is a longitudinal sectional view of a spray can employing the teachings of the invention; and
FIG. 9 is a modified version of spray can utilizing the inventive teachings.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Describing now the drawings, the exemplary embodiment of dispenser device shown by way of example as a fountain toothbrush in FIGS. 1 and 2 will be seen to comprise as its main parts or components a bristle carrier 3 which carries at its one forward end a set of bristles 4. This bristle carrier or support 3 possesses about the face or end surface 3a which faces away from the end carrying the bristles 4 an extension in the form of a rigid-walled sleeve 5 which simultaneously serves as a handgrip or handle and is open at its rear end 5a. A cartridge 10 containing the filled material i.e. the material which is to be dispensed, in this case a liquid or pasty dentifrice is inserted through the open handle end 5a. A duct or passageway 2 extends through the bristle carrier 3 from its rear end face 3a up to the region of the bristle-carrying end of such bristle carrier 3 and opens by means of a lateral outlet channel or duct 2a between the bristles 4. Moreover, the cross-section or diameter of the duct or passageway 2 is structured at one location preferably in such a manner that it exerts a capillary action on the dentifrice flowing therethrough depending upon the viscosity of the latter. By virtue of these measures there is extensively avoided unintentional flow of dentifrice out of the outlet opening of the outlet duct or channel 2a when the dispenser device, in this case the fountain toothbrush, is in its non-actuating position, even when the fountain toothbrush is held with the bristles 4 pointing downwards and is shaken or jarred or flung about.
A piston 7 having an axial passage or passageway 17 is pressed with a tight fit into the widened end region or throughflow end 2b of the duct or passageway 2. The dentifrice-containing cartridge 10 is inserted in the sleeve 5 forming the handle and possesses at its end wall 10b directed towards the interior of the sleeve 5 a throughflow chamber or a cylinder sleeve part or connection 8. The cylinder sleeve part or connection 8 has an internal chamber or passage 9 which flow communicates with the internal space or chamber 10a of the cartridge 10 by means of an opening 11. The cylinder sleeve part 8 is arranged in the inner end wall 10b of the cartridge 10 in such a manner, and its diameter is designed such, that upon insertion of the cartridge 10 the piston 7 enters the cylinder sleeve part 8 and can sealingly slide therein. The cylinder sleeve part or connection 8 thus forms a pump cylinder which is associated with the piston 7. Prior to its insertion into the sleeve 5, a new, dentifrice-filled cartridge 10 is sealed by a membrane-like closure 11 b across the opening 11, as best seen by referring to FIG. 3. The path of insertion of the cartridge 10 is limited by a nose or nose member 10c provided on the outer cartridge wall, this nose member being snapped into a groove or recess 5b of the wall of this sleeve 5, and also is limited by impact of the nose 10c against the end wall of the groove 5b which is displaced forwards in axial direction, i.e. towards the bristles 4.
A recess 13 provided in a part of the rear end wall 3a of the bristle carrier 3 and located internally of the sleeve 5 defining the handle and another recess 14 provided at an oppositely situated front end wall 10b of the cartridge 10 facing towards the bristles 4 are aligned with one another and receive therein, respectively, the opposite ends of a compression spring 15 which serves as a return spring for urging the bristle carrier 3 and the cartridge 10 apart. The displacement of the cartridge 10, due to the action of the compression spring 15, outwardly of the open rear end of the sleeve 5 is limited by the abutment of nose 10c of the cartridge 10 against the transverse rear end wall of the groove 5b. Consequently, cartridge 10 is prevented from dropping out of the handle formed by the sleeve 5. On the other hand, when pulling more intensely on the rear end of the cartridge 10 protruding from the open end of the sleeve 5, the somewhat flexible nose 10c can be forced to slip out of the groove 5b, and thus for instance it is possible to remove an empty cartridge from the sleeve 5 and to replace the same by a new, full cartridge. Instead of constructing the nose 10c to be flexible or resilient, it is equally possible to also design the wall of the cartridge 10 to be somewhat flexible or resilient, especially in the vicinity of the nose 10c in order to serve the same purpose.
Now if instead of the groove 5b there is provided a window as shown in FIG. 1, then the nose 10c can be pressed slightly inwardly e.g. with a fingertip and at the same time can be disengaged or dislodged from the groove 5b by simply pushing it outwardly, whereupon the cartridge 10 can be easily pulled out of the sleeve 5. For this purpose, the window 5b also can be located near the other end of the sleeve 5 e.g. towards its central or middle region. A pin or mandrel pin means 19 which projects outward of the end face or side 7a of the piston 7 which is located opposite the cartridge 10 serves to rupture the previously discussed cartridge membrane 11a when the cartridge 10 is inserted far enough into the sleeve 5. Preferably this occurs at the same time as the nose 10c snaps into the groove or window 5b, or however shortly beforehand.
During the manufacture of the bristle carrier 3 together with the sleeve 5 of the previously described fountain toothbrush, difficulties are associated with the manufacture of the narrow, long duct or passageway 2, because the required long, thin core needle used during injection molding can easily break or become bent. Hence, the passageway or duct 2 is manufactured of a larger diameter than is desirable for a controlled outflow of the material to be dispensed, here the dentifrice. Thus, in the wide passageway or duct 2 there can be fixedly inserted a conduit element 32, preferably in the form of a hollow needle having a narrow axial channel 33 therethrough. In the widened region or zone 2b of the passageway or duct 2 which is situated towards the bristle carrier-end wall 3a there is fixedly seated or otherwise fixedly connected, upon the end 32a (FIG. 4) of the conduit element 32 which protrudes out of the region 2b of such duct 2, the open end 7c of the piston 7 which confronts the bristle carrier 3.
At end surface or face 7a confronting the cartridge 10 the piston 7 is equipped with a circumferential elastic sealing rim or edge 7b. This sealing rim or edge 7b sealingly bears against and is guided at the inner wall 8a of the cylinder chamber 9 of the cylinder sleeve part or connection 8.
The axial piston passage 17 which extends through the piston 7 opens at one end at the center of the piston end or frontal face 7a and is provided at the middle or central zone of the piston 7 with a conically bevelled ring or annular shoulder 16. This annular shoulder 16 serves as a valve seat and merges with the throughpassage region or passage zone 17b of wider diameter, and which zone extends from the ring shoulder 16 to the passage opening or throughpassage opening 17a facing towards the bristles 4.
In the throughpassage 17 there is housed a valve body 18 possessing a sealing portion 18a of larger diameter and a sealing disc or gasket 20. The latter can sealingly bear at the inner surface of the transverse wall 11a separating the interior of the cylinder chamber 9 from the interior 10a of the reservoir in the cartridge 10, thereby closing the opening 11 located in such transverse wall 11a. At the abutting or sealing disc 20 there is provided pin 19 which protrudes into the opening 11 and by means of the latter into the interior or inner space 10a of the cartridge 10. The diameter of the pin 19 is slightly smaller than that of the opening 11.
The upperside 18b of the sealing ring portion 18a, which side confronts the bristles 4, can be brought into abutting contact with the end face or wall 7a of the piston 7 and carries a valve stem 21 which protrudes into the piston passage 17 past the valve seat 16 in the direction of the bristles 4. The wall 7a and upperside 18b of the sealing ring 18a form stop means for limiting the movement of the valve body 18. The valve stem 21 is enlarged at its one end in the form of a head 22 defining a closure member and possesses at the side of the head which faces away from its end a preferably conically bevelled valve sealing surface or face 22a. The latter is constructed such that it can sealingly bear upon the valve seat 16. At least one of the valve seat 16 or closure members 22 is elastically deformable so that the closure member can be inserted through the valve seat.
The spacing between the contact surface of the abutting sealing disc 20 at the opening 11 and the valve sealing surface 22a of the head 22 of the valve body 18, on the one hand, and the spacing between the end surface 7a and the valve seat 16, on the other hand, are dimensioned such that when the piston 7 sealingly bears with its end wall or face 7a at the upperside 18b of the sealing ring portion or part 18a and, when the outer face or surface of the abutting sealing disc 20 sealingly bears at the transverse wall 11a of the cylinder sleeve part or cylinder chamber 8, and which transverse wall 11a contains the opening 11, the valve head 22 is lifted from the valve seat 16. This occurs against the force of a valve resetting spring 23 which is arranged between the upperside of the abutting sealing disc 20 directed towards the piston 7 and the end wall 7a of the piston 7 and strives to sealingly press the valve head 22 against the valve seat 16.
In lieu of a single central throughflow channel 33 there can be provided in the outer wall of the conduit element 32 also two or more, for instance four longitudinal grooves 33a, as best seen by referring to FIGS. 6 and 7. In the end region 32a of the conduit element 32 these longitudinal grooves 33a are covered by the inner wall of the passage 17 in the open end region 7c of the piston 7 and downstream thereof are covered by the inner wall of the duct or passageway 2 in the bristle carrier 3 and, thus, form a multiplicity of throughflow channels, the individual cross-sectional areas of which can be held so small by providing correspondingly flatter or narrower cross-sections of the grooves 33a that they strive to carry out a desired capillary effect on the liquid dentifrice.
Having now had the benefit of the foregoing description of the exemplary embodiment of dispensing or dispenser unit in the form of a fountain toothbrush the same is used in practice in the following manner:
Initially during introduction of the cartridge 10 into the handle formed by the sleeve 5, while piercing the membrane 11b closing the opening 11 by means of the pin 19 which is held in position relative to the cartridge 10 owing to the abutment of the sealing part 18a at the base portion 7a of the piston 7, the bristle carrier 3 and the cartridge 10 assume the position depicted in FIG. 5. In this position the abutting gasket disc 20 closes the opening 11 against which it has already been pressed approximately prior to reaching the position of FIG. 5 by means of the compressed valve compression spring 23. Now if under the action of the stronger return or restoring spring 15 the cartridge 10 is moved within the sleeve 5 away from the end surface or face 3a of the bristle carrier 3, then such cartridge also moves relative to the piston 7 which thus sealingly bears in contact with the sealing rim 7b at the inner wall 8a of the cylinder chamber 9 until it has reached the position shown in FIG. 4. During this movement the abutting gasket disc 20 initially still retains the opening 11 closed in that the spring 23 is not completely untensioned, even when the valve head 22 has already reached the valve seat 16.
During further displacement of the cartridge 10 by the compression spring 15 the valve body 18 is fixedly held by means of the valve sealing surface 22a at the valve seat 16 and the sealing disc 20 frees the opening 11. Consequently, when the toothbrush is held with the bristles 4 directed downward even a viscous dentifrice or other material to be dispensed will be suctioned into the pumping space defined by the cylinder chamber 9. Any air which is present in the pumping space of the cylinder chamber 9 ascends in the form of bubbles to the outer, upper end 10b of the cartridge 10 (FIG. 4).
Now if during application of pressure upon the protruding end 10d of the cartridge 10 the piston 7 is again shifted in the cylinder chamber 9 into the position shown in FIG. 5, then initially the opening 11 is closed due to abutment of the abutting disc 20 and then during the further course of the cartridge- and piston movement, respectively, the spring 23 is compressed and thus the valve seat 16 is moved away from the valve head 22. During progressive penetration of the piston 7 into the pumping or cylinder chamber 9 liquid is forced between the valve seat 16 and the valve head 22 and pressed into the throughflow channel 33 until the end face or wall 7a abuts against the upperside or stepped portion 18b of the ring-shaped or annular part 18a.
Upon release of the cartridge the cylinder chamber forming sleeve part 8 and the piston 7 again return from the position shown in FIG. 5 back into the position shown in FIG. 4 and the fountain toothbrush is again ready for dispensing a new dose of liquid dentifrice to the bristles 4.
A fountain toothbrush having a piston part introducible into a rigid-walled rearwardly closed reservoir and a valve mounted in the frontal wall of the piston part has been descrived in U.S. Pat. No. 3,227,165 to Constanza. However, with this prior art fountain toothbrush, the valve consists of a slotted rubber valve which does not allow for any dosed dispensing of the liquid dentifrice to the bristles.
Good closure of the opening 11 of the cartridge 10 is of decisive importance for the positive functioning, especially also for the exact dosed delivery of liquid for the fountain toothbrush of the present invention. To this end there is required a sufficiently strong spring 23 and a sufficiently narrow intermediate space between the valve stem 21 and the inner wall 17b of the axial piston passage 17.
In order to demonstrate the manifold possible fields of application of the described dispenser device, there will hereinafter be considered a number of other applications. The handle of the illustrated fountain toothbrush with the valve arrangement housed therein and the cartridge can be used, for instance, directly as the bristle carrier for a hand brush or the like. Such handle or handgrip furthermore could possess a particular aesthetic construction, wherein the cartridge can contain cosmetics or the like. In the same manner it is however also possible to use the dispenser device for the dispensing of medication, by virtue of the dosage accuracy. The particular characteristics or aspects of the invention come fully into play especially when using the same in the environment of a fountain toothbrush, since such device often is carried in a pocket book or the pocket of a jacket or the like, so that there must be present both positive operation reliability in conjunction with absolute lack of leakage of the material to be dispensed. It has been found in practice that in the case of a fountain toothbrush, as previously described, these requirements are totally fulfilled.
What has been explained heretofore is analogously applicable with regard to the embodiments of spray cans shown in FIGS. 8 and 9. As a matter of simplicity the same or slightly modified reference characters have been conveniently employed for the same components, so that further detailed explanations are not believed to be necessary beyond what is stated hereinafter. The pump is accommodated in a container cap or closure 50 which is attached at the reservoir or cartridge, possibly so as to be exchangeable. The piston 7 engages by means of its piston rod 60 into an actuation part or component 51. A hose 53 merges with the opening 11.
With the embodiment of FIG. 9 the closure 50 is provided at the end of the cartridge or reservoir 10 which faces away from the actuation part 51. Instead of using the hose 53, in this case there are provided the connection channels 53a. The piston 7 is connected with the actuation part by means of a tube 54.
The narrow passage moreover forms an especially effective throttle location or throttle means, also upon release of the cartridge, and which prevents sucking-up of undesirable amounts of air. The negative pressure which prevails in the cylinder compartment due to the throttling action can bring about lifting of the valve plate or sealing disc 20 from its seat before the valve head 22 will be seated upon its seat 16.
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 with the scope of the following claims. ACCORDINGLY, | A dispenser device comprising a reservoir for a flowable or fluent filled material as well as a piston pump equipped with a valve arrangement. The valve arrangement is coaxially dispositioned with regard to the pump and possesses parts connected with the piston and parts connected with the cylinder of the piston pump. | 5 |
This application is a continuation of application Ser. No. 07/384,707 filed July 25, 1989 now abandoned.
FIELD OF THE INVENTION
This invention relates to a moving beltway for use by pedestrians or for the movement of goods and is particularly applicable, but not restricted, to moving beltways which have sections running at different speeds.
BACKGROUND OF THE INVENTION
Previous moving beltways have suffered certain disadvantages.
If they are to be a constant speed beltway the surface has either been very heavy belting or metal treads located on a carrier frame and each of these are inherently expensive and also provide mechanical problems in siting, in that when they are to return they need a substantial diameter roller, as the radius about which they can turn is large. This may involve the building of a pit or the like at each end of the beltway to receive the rollers.
A further major problem with moving beltways, quite generally but particularly if they are to be of variable speed or are long has been the translation of the user between a stationary position and the beltway and between adjacent parts of a beltway. This latter aspect has been considered most serious for two reasons. Firstly such transistions are normally required to be effected where the beltway is one which has a variable speed and thus the transition is occurring at a higher absolute speed than is the case with moving onto or off a standard beltway moving at a slow speed.
This means that whilst the relative speed between the two adjacent sections of beltway are relatively small, the belts or the like comprising the surfaces of the beltway are both travelling at relatively high speeds adjacent to the surrounding ground or wall defining the sides of the beltway.
Thus, should, for example, a user fall or an article attached to a person, such as part of a shoe a trailing portion of a garment or the like be caught between the belt or the plate or comb at the transition then the likelihood of injury is substantially greater than would be the case if the same accident occured on a slower speed beltway section.
There have been proposed ways in which to attempt to overcome these problems, but they have not been satisfactory and have not been commercially adopted.
They include the use of transfer plate sections which are movable in a plane normal to the beltways and the concept of short lengths of narrow belts which overlap in the direction of movement thereof, and belts which are at different levels so that a user has to physically step from one belt upwardly or downwardly to the next adjacent belt. Also where the belts are ribbed, which has normally been the case, the transfer area must include combs, and where the belts are heavy and are passing over relatively large diameter rollers, it has been practically, extremely difficult if not impossible to maintain accurate narrow spacings between the combs and the belt when the belt is travelling at a high speed.
SUMMARY OF THE INVENTION
The first object of the present invention is to provide a beltway arrangement which can minimise the problems and which can be used either as a constant speed or variable speed beltway.
A second object of this aspect of the invention is to provide in a moving beltway transitions between two beltway portions or a stationary end and a beltway portion which effectively prevent any part of a passenger or his or her clothing or accoutrements on the beltway being caught on or by part of the beltway or its components. The invention includes, in its broadest sense, a beltway comprised of at least one beltway section which has two spaced small diameter rollers which define the ends of the section, drive means and a thin flexible continuous slider belt which is adapted to pass over the rollers defining the ends of the section and to be driven by the drive means.
At each end of a horizontal length of belt there can be a plate having an inner edge formed to closely abut the belt as it passes around the roller at the beginning or end of its run, the upper surface of the plate being smooth to facilitate easy transition thereacross and the spacing between the edge of the plate and the upper surface of the belt being small, generally less than 1.0 mm, to prevent articles passing therebetween.
The beltway can comprise a number of adjacent belt sections each of which closely abut the next adjacent section and this is essential where the beltway is to be one on which the speed varies along the length.
In such an arrangement the beltway can also have a long "central" section which operates at a constant speed and which has shorter beltway sections adjacent each end thereof.
In one aspect of this, the invention includes a junction between two beltway sections wherein there is a transfer plate between the two sections characterized in that at least part of the upper surface of the transfer plate is located at a level below the level of the upper surface of the preceding belt.
In a specific arrangement the surface of the transfer plate is curved downwardly so that the edge of the transfer plate which is adjacent the end of the delivery belt section is at a lower level than the central portion of the transfer plate.
The arrangement is specifically useful for a beltway travelling at relatively high speeds.
In an alternative aspect which is suitable for relatively low speed beltways we use ribbed belts for at least some portions of the beltway and the combs used with these belts are so formed as to have longitudinal members which are narrower than and shallower than the spacing between the ribs of the belt running the length of the belt between two transfer plates.
This arrangement means that a person wearing a normal shoe or any reasonable sized body is supported by the ribs of the belt but any narrower body such as, for example a woman's spike heel which can fit between the belt ribs can rest on the longitudinal member between adjacent ribs but will slide along this member. As a person's shoe is transferred from one belt to the next the heel will be automatically carried onto the transfer plate and subsequently onto the next belt section.
The longitudinal member may be rods or bars.
Such an arrangement is preferably only used on the lower speed portions of the beltway as they are not necessary for the higher speed portions.
BRIEF DESCRIPTION OF THE DRAWINGS
In order that the invention may be more readily understood, reference will be made to the accompanying drawings in which:
FIG. 1 is a schematic view of part of a beltway of the invention;
FIG. 2 is a side sectional elevation of one of the modules of the beltway;
FIG. 3 is an enlarged view showing the arrangement at the junction between two modules;
FIG. 4 is a view similar to FIG. 3 but showing a modified form of transfer;
FIG. 5 is a schematic view showing the relationship between a ribbed belt having rods in the ribs and a higher speed belt using a transfer plate similar to that of FIG. 4; and
FIG. 6 is a sectional view along line 6--6 of FIG. 5.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The specifically illustrated embodiment shows an arrangement which is for a beltway having variations in speed along its length but, as will be described hereinafter, the invention also relates to a constant speed beltway.
The beltway can be deemed to be made up of a number of independent modules 2 and these modules may be individually replaceable so that should there be a fault in any particular module it can readily be removed and replaced thus limiting the down time of the beltway.
Referring specifically to FIG. 1, there are a number of modules 2 each of which has a roller 15 at each end thereof and a belt 20 passing thereover.
For convenience, where required, and when referring to adjacent beltway sections, we shall use the term delivery and receiving to indicate the appropriate section.
The belt 20 passes beneath a pair of idler rollers 25 and is driven by a driver roller 31a. One or more of the idler rollers 25 may be adjustable to enable the belt 20 to be tensioned.
It will be seen from the schematic in FIG. 1, that the top runs of the belts 20 normally lie in the same plane and can as better be seen from FIGS. 2 and 3 because the overall spacing between the belts 20 is only minimal.
If changes in grade are required, the planes of the top runs of the belts can be at angles to each other.
The first or last sequence of belts in a system would be relatively short, the upper run could be of the order of 300 to 1000 mm. The belts 20 can be relatively thin and this permits the belts to pass over pulleys of a very small diameter. For example the diameter of the pulleys 15 could be of the order of 30 to 70 mm.
This means that the effective space between the adjacent portions of the upper run is only of the order of 20 to 40 mm which is substantially less than the length of a user's shoe, even if the user has only a very small foot, such as a child. The under-surface of the upper run of the belt is supported on a slider plate 26.
Located between each pair of modules there is a plate 10 which has an upper surface 11, which may be polished which provides a low friction surface for the footwear of a user of the beltway so that if the user is standing on the beltway with his or her feet substantially parallel to the direction of movement of the beltway then they will be transferred from one module to the other with no difficulty whatsoever.
As can be seen specifically from FIG. 3 the edge 14 of the plate 10 is adapted to closely approach the thin belt 20 as it passes over the small diameter roller 15.
The tolerance of the thickness of the belt is controlled so that the spacing between the periphery of the roller 15 and the edge 14 of the plate 10 defines a passage which is only slightly greater in width than the thickness of the belt so that as the belt passes under or leaves from the outer edge of the plate 10 the spacing between that edge and the belt 20 is very small so articles can not be drawn therein.
It is preferred that the tolerance is such that a flowing piece of material, such as a belt or the hem of a coat or a dress cannot readily pass therebetween.
It is also preferred that there is a sensor associated with the junction so that if anything should enter the spacing, the belts are stopped.
Adjacent to the terminal or downstream end of the highest speed module 2 there is a long belt 27 which can provide the central part of the beltway.
Although not fully illustrated, it is preferred that the drive rollers 31a are all driven from the same power source or that the power sources be centrally controlled so that if there is any failure in the drive this effects all of the modules equally and at the same time, so that there can be no inherent difficulty which could occur if a person is moved from a moving module to a stationary module.
The pulleys or gearing between the modules and the drives can be different diameters so that there can, over the length of the beltway, be a gradual increase in speed from an initial speed which is acceptable to a passenger entering a beltway, for example between 0.4 to 0.9 meters per second up to a speed which could be as high as 3.5 meters per second, and then a reduction in speed through a number of modules to an exit speed of, again, 0.4 to 0.9 meters per second.
The sequence of short belts operate so that each belt travels somewhat faster or slower than its neighbours. In this way the passengers on the beltway are speeded up on the acceleration section at the start of an installation, and slowed down at the end of it. By the time the passengers reach the long central section of constant speed belting, the spacing between the passengers is increased above the entrance spacing by the ratio of the speed of the constant speed belt to the speed of the first belt. The belt is therefore subjected to a lesser loading than it would have had if it was the only belt in the installation, and it does not have to contend with the acceleration forces of the smaller belts. In these circumstances it is possible to use a thin slider belt for the constant speed section which is capable of being returned about a 30 to 70 mm diameter roller, as are the short belts and can therefore be brought within 20 to 40 mm of the last accelerating or the first decelerating belt from which it will be separated by the plate 10 which is tha same as the plates between the modules.
The length of run of the constant speed belt will be determined by its vertical profile, its relative speed and the space available for the drive motor.
Longer passenger runs can be achieved by providing adjacent slider belts separated by plates 10 and which run at the same speed.
Changes of grade may be effected by introducing one or more sections of short belt, providing belts tangential to the theoretical sag curve between a horizontal belt, and a belt with a positive incline, each belt passing around smaller rollers 15 and separated by plates 10. Over summit changes of grade the vertical profile of the slider plate can guide the long thin belt.
In the foregoing we describe arrangements, basically by using thin belts that can pass over narrow rollers, whereby the spacing between two adjacent belt sections in a moving beltway can be limited and, in these arrangements, we have described relatively narrow transfer plates which have a smooth upper surface over which portions of the shoes or other articles associated with a user and in contact with the belt can pass as there is transition from belt to belt.
It will be appreciated that there are practical difficulties in providing tolerances between the belt and the transfer plates which are so fine that it is not possible for an article, say such as a thin piece of dress material to pass between these if the flexible material is pressed against the opening by a solid object which by its weight eliminates the irregularities in the material which is abutting the opening and, of course, if such can occur then injury could be caused to the user. One method of avoiding or minimizing this difficulty is the provision of sensors as previously described.
We have calculated that this problem can be greatly reduced by locating the transfer plate below the level of the belts and by forming the upper surface of the transfer plate.
The transfer plates have a width of the order of 30 mm and on almost all occasions a user will transfer across the plate with the heel of the shoe, or even part of the sole of the shoe remaining on the delivery belt until after the leading edge of the shoe is received on the receiving belt and thus there will only be minimal contact, if any, with the transfer plate.
In accordance with this aspect of the invention and as illustrated in FIG. 4, which contains dimension solely for exemplification, we physically locate the surface of the transfer plate 50 below the level of the belts 20, which can have a thickness of approximately 3 mm and we have found by calculation that provided that this spacing is of the order of 3 mm if the belts are moving at a speed of even 0.6 m/sec then it is effectively impossible for any part of the user or any solid article carried by the user to contact the gap beteen the transfer plate and the belt.
As can be seen from FIG. 4 the horizontal distance from the tangent point of the belt to the point at which the belt comes into close abutment to the edge 14 of the transfer plate 50 is 12 mm. At a belt speed of 0.6 metres/sec it will take a body some 15 mm in forward movement before it will drop 3 mm in vertical movement and thus any body leaving the belt will not strike the transfer plate 50 until it passes the gap.
This however is very much at the lower end of the speed to which the invention relates.
If the belt is travelling at 0.9 meters/sec then the distance travelled before dropping 3 mm is 23 mm and if at 1.2 meters/sec, which is the lower order of speed we would anticipate from the fastest belt then the distance travelled would be 30 mm. These distances are derived using a vertical acceleration of 1 g which would usually be the downward acceleration of a solid body and some consideration must be given to the situation as far as an elastic body is concerned.
At the somewhat higher speeds it can be shown that for a body to approach the gap between the edge 14 of the transfer plate and the belt there would need to be a downward acceleration of approximately 3 gs.
An elastic body, such as a balled up or compressed piece of fabric could accelerate at more than one g but normally this would tend to expand to a rest position with the overall acceleration in any direction being substantially less than 3 gs.
Also it will be appreciated that any article which is so accelerating will tend to be folded or bunched so it is unlikely that there would be a clean edge portion which would pass between the belt and the edge 14 of the transfer plate, unless the article was pressed upon by a solid object.
Whilst in the foregoing embodiment we have not described the actual surface of the transfer plate it would be possible to provide a profiled transfer plate of the type illustrated in FIG. 4 which would operate in the same way as described but which would, minimize, apparent change in level for a person passing thereover.
In a variation of the profile the edge of the plate abutting the preceding belt may be shaped to further lower the position of the belt/transfer plate edge abutment so that there is additional room for elastic material to unfold. Solid object will bridge the gap and contact the central portion of the transfer plate which is higher than the edge portions.
We could also provide an additional means which would act to prevent any entrance of material into the gap between the belt and the transfer plate.
This would be by providing a relatively powerful air draft passing upwardly from beneath the upper run of the belt and through the spaces between the belts and the edges of the transfer plates.
This air blast would of course act to prevent any light elastic object from approaching the gap whilst it would have no effect on solid objects.
Where the belt way is operating at a high speed, and depending upon the spacing between the belts it would be possible to omit the transfer plate completely.
A solid object would travel across the gap without making any contact and an elastic object would be unlikely to make contact, for reasons set out hereinbefore.
Even if an elastic object closely approached the belt surfaces it is most unlikely that it could be ingested as at the junction the two belts are moving in opposite directions and as the object is carried forwardly across the gap it would contact the belt which was moving in a direction away from the gap.
These, apparently, minor modifications greatly increase the safety of a moving beltway which separates individual belts by stationary plates, as it makes the transfer safe and effectively removes any likelihood of injury due to parts of a person's clothing or any other thing from entering the gap between the edge of the transfer plate and the belt.
These aspects of the invention are less applicable at lower speeds where a solid object such as a childs body or a shoe could, falling under 1 g of acceleration, so closely follow the elastic material that it could press the material aginst the slot and result in ingestion of the material. This prospect is increased at the end of the system where a body may come to rest over the transfer plate.
While we believe that such an occurrence will be so infrequent that the sensor triggered system shut-down will prevent more than slight scuffing some National Codes may require an alternative solution using ribs and combs.
At such junctions, therefore, different means may be required to ensure that articles are not gathered between the edges of the transfer plate. One particular way of ensuring safety at lower speeds is to use a modification of ribbed belts, which are often used in beltways.
Ribbed belts are, at each end, normally associated with combs which enter the recesses between the ribs and, hopefully, deflect any article which is resting on the belt over their top surface onto the transfer plate, or to the stationary area adjacent the end of the belt.
These are generally satisfactory but there have been many occasions where articles attached to persons have been caught on the comb or between the belt and the comb and persons can be injured in this way. Broken combs are common and when broken present a greater entrapment potential.
In a further aspect of the invention, which is described illustratively in FIG. 5 we effectively extend the teeth of the combs along the whole length of the belt between two adjacent combs.
These extensions can be in the form of rods or bars 60 which have a width less than the spacing between adjacent ribs 61 and a height less than the height of the ribs so that they actually lie below the surface of the belt 62.
It will be appreciated that these rods 60 have a certain degree of flexibility but provided they are made of such material as chrome plated steel or the like they will not provide a stong frictional resistance where contacted by the belt and, also where there is an article resting on them they will act as a slider plate.
Under normal circumstances if there is a user standing on the belt then there will be no contact with the rods as the width of any part of a normal shoe is wider than the spacing between a pair of ribs.
There may however be circumstances where there are narrower articles which can fit between two adjacent ribs and one of these would be the heel of a spike heeled shoe or possibily something such as the edge of an article such as a brief case.
In such a case the article could rest on the upper surface of the rod and slide therealong but when it reaches a transfer plate it will automatically be moved directly onto the transfer plate and cannot pass between the transfer plate and the belt.
It will be seen that possibly the most desirable arrangement for a high speed beltway would be to have the initial or, say the first two or three belts with ribs having rods located between the ribs, the central portions of the beltway using flat belts with transfer plates between belts and below the level of the belt and the terminal portion or portions being ribbed and having rods located between the ribs, generally as illustrated in FIG. 4.
In an extreme case the highest speed transfers could be effected without transfer plates.
This would ensure safety both at the low speed portion of the beltway as well as at the high speed portions.
Where belts which can pass around a very small radius are used it may be that the ends of the sections can be defined by a radiused end of a slider plate and the belts can pass over these radiused ends.
Normally the belt would pass through slightly more than the angle necessary to be normal to the upper run, so that the belts of adjacent sections diverge slightly then normally pass around a roller which may define the commencement of the lower run.
Various modifications can be made in the described form of the invention without departing from the spirit and scope thereof. | A beltway comprised of at least one beltway section which has two spaced small diameter rollers which define the ends of the section, a drive unit and a thin flexible continuous slider belt which is adapted to pass over the rollers defining the ends of the section and to be driven by the drive unit. At junctions between two beltway sections a transfer plate is located. The transfer plate is formed to terminate close to the belt on either side thereof so that there is a smooth transition from the belt to the transfer plate and is of a width, in the direction of movement of the beltways, such that a user is in contact with the receiving beltway before losing contact with the delivery beltway. | 1 |
BACKGROUND OF THE INVENTION
This invention was made in the course of a contract with the United States Department of Energy.
The invention relates generally to an extension and improvement of the utility of a centrifugal fast analyzer for blood serum analysis. More specifically, it relates to a capillary disc and rotor arrangement which prepares and simultaneously delivers each of a series of prepared and precisely measured serum sample aliquots to individual cuvettes in an analytical rotor.
Centrifugal fast analyzers (CFA), along with modifications and improvements, have been previously described in various disclosures and patents. See, for example, U.S. Pat. Nos. 3,555,284 and 3,798,459. A multiple-sample centrifugal rotor for blood fraction preparation has been described in U.S. Pat. No. 3,864,089. As taught therein, liquid or cell suspension products are removed by means of some type of withdrawal probe or pipet for analytical purposes. An improvement in that device is disclosed in U.S. Pat. No. 3,890,101 in which blood fractions are collected in removable containers or vials from which measured analytical samples are taken.
Ancillary equipment required for routine operation of these systems includes a sample and pipetting device, as described in U.S. Pat. No. 3,854,508, for loading aliquots of sample and reagents into chambers in the CFA rotor. Such loading devices are expensive, mechanically complicated and require considerable preventive maintenance. In clinical work, it would be of considerable advantage to eliminate the manual manipulations required of these devices by direct transfer of prepared, accurately measured blood serum samples to the cuvettes of an analytical rotor.
SUMMARY OF THE INVENTION
It is accordingly an object of the invention to provide a method and apparatus for preparing serum samples from whole blood.
It is another object of the invention to provide a method and apparatus, as above, in which precise aliquots of serum are loaded automatically into serum capillaries.
It is still another object of the invention to provide a method and apparatus, as above, which eliminates manual manipulations of serum samples during transfer to an analytical rotor.
It is yet another object of the invention to provide a method and apparatus, as above, which eliminates the need for ancillary equipment in serum sample preparation and transfer to an analytical rotor.
These objects and others are achieved by an apparatus for preparing blood samples for analysis, comprising a whole blood sample disc having a plurality of first radial passageways arranged therein in spoked array, each first passageway removably receiving a capillary tube for a whole blood sample; a serum sample disc secured to the whole blood sample disc and having a plurality of second radial passageways arranged therein in spoked array, each second passageway removably receiving a capillary tube; a sample preparation rotor having a center cavity for receiving and holding the whole blood and serum sample discs, the rotor including a plurality of separate cavities at the outer periphery thereof, the first and second radial passageways of the discs being oriented such that each of the whole blood sample capillary tubes is aligned with a single serum sample capillary tube to define a pair, each pair of capillary tubes being in fluid communication with a separate cavity; and means for rotating the sample preparation rotor to separate the whole blood samples into serum and solids in the separate cavities; wherein the serum migrates by capillary action from the cavities into the serum sample capillaries after rotation of the sample preparation rotor is halted.
The apparatus can further include an analytical rotor having a center cavity for removably receiving the serum sample disc and capillaries, and having a plurality of cuvettes and means for dispensing a measured amount of analytical reagent to each of the cuvettes; each of the serum sample capillaries being in fluid communication with a separate cuvette; and means for rotating the analytical rotor to effect transfer of the serum from the serum sample capillaries to the separate cuvettes for mixing with the dispensed analytical reagent.
The objects of the invention are further achieved by a method for preparing blood samples for analysis, comprising the steps of obtaining whole blood samples in a plurality of capillary tubes, placing each capillary tube in a separate radial passageway of a whole blood sample disc; placing the whole blood sample disc in a sample preparation rotor; disposing a serum sample disc above the whole blood sample disc, the serum sample disc having a plurality of empty serum capillary tubes received within radial passageways; aligning each empty capillary tube with a separate whole blood sample capillary tube to form a pair; aligning each pair of capillary tubes with a separate cavity along the periphery of the sample preparation rotor; rotating the sample preparation rotor to effect transfer of the whole blood samples from the capillaries to the cavities by means of the centrifugal force generated by rotation of the rotor; centrifugally separating the whole blood samples in the cavities into serum and solids by continued rotation of the rotor; stopping rotation and allowing the serum to migrate by capillary action into the serum capillary tubes; removing the serum sample disc from the sample preparation rotor and placing it in an analytical rotor containing a plurality of cuvettes and a means for dispensing analytical reagent into the cuvettes, each serum capillary tube being aligned with a separate cuvette and in fluid communication therewith; rotating the analytical rotor to effect transfer of the serum samples from the capillaries to the cuvettes by means of the centrifugal force generated by rotation of the rotor; transferring analytical reagent to each cuvette, the serum samples being mixed with the analytical reagent by continued rotation of the analytical rotor; and analyzing the serum samples.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a top view of a whole blood sample disc constructed in accordance with this invention;
FIG. 2 is a top view of a serum sample disc;
FIG. 3 is a top view of a sample preparation rotor;
FIG. 4 is a cross-sectional elevation of the sample preparation rotor with blood sample disc and serum sample disc inserted; and
FIG. 5 is a top view of an analytical rotor.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present invention is a CFA-based disc and rotor system providing a means for processing measured whole blood samples into serum and solids (red cells and platelets), followed by aliquoting and transferring measured samples of the serum into the cuvettes of an analytical rotor. The system utilizes precision bore capillary tubes for volume measurement and comprises (1) a whole blood sample collection disc, (2) a sample preparation rotor, (3) a serum sample collection disc, and (4) an analytical rotor. The whole blood and serum sample collection discs are each equipped with a plurality of precision bore calibrated capillary tubes into which samples are loaded by capillary action. The samples are centrifugally discharged from the capillaries by high speed rotation of the rotors. Thus, a number of whole blood samples individually loaded into the capillaries of the whole blood sample disc are simultaneously transferred to cavities in the sample preparation rotor where they are centrifugally separated into serum and solids. The serum samples are individually and automatically loaded into empty capillaries of the serum sample disc by capillary action after the rotor is stopped. The filled serum capillaries are subsequently deposited into cuvettes of the analytical rotor, by centrifugation, for analysis by conventional photometric methods. This operation is accomplished withou the need for a special pipetting station such as that mentioned hereinbefore, or manual manipulation of the samples.
As shown in FIG. 1, a whole blood sample disc is indicated generally by the number 1. A plurality of precision bore capillary tubes 3 (four shown) are removably inserted into equally spaced radial passageways 5 arranged in spoked array in the disc 1. Each tube is atmospherically vented by way of a smaller passageway 7 connecting the radially inward end of the tube to an opening 9 through a raised, preferably circular center section 11 defining a hub. The tubes are held in place by suitable means such as an o-ring 13 positioned within a circular groove 15 that passes transversely across the tube-holding passageways. When the tubes are inserted, they are frictionally engaged by passing over and compressing the o-ring.
Referring to FIG. 2, a serum sample disc, indicated generally by the number 17, comprises a plurality of precision bore capillary tubes 19 (four shown) removably inserted into equally spaced, radially arranged passageways 21 in disc 17. Each serum tube extends from the disc 17 in a spoked array and is atmospherically vented at the inner end by way of a vent groove 23 near the center opening 25. As in the whole blood sample disc, the tubes 19 are held in place by, for example, an o-ring 27 positioned within a circular groove 28 passing transversely across the tube-holding passageways 21. The o-ring is compressed as the tubes are inserted into the passageways. The center opening 25 in the center of the disc 17 accepts the raised circular section 11 at the center of the whole blood sample disc 1 to facilitate a precise mating of the two discs.
A sample preparation rotor is shown in FIGS. 3 and 4 and is indicated generally by the number 29. The rotor 29 has a circular rotor body 31 with a center cavity 33 for receiving and holding the whole blood and serum sample discs. A multiplicity of radial slots 35 (four shown) are preferably provided in the outer raised portion of the rotor body to accommodate the capillaries 3 and 19 of the discs. The outer end of each slot communicates with a cavity 37 near the outer periphery of the rotor body by way of a passageway 39. The cavities and passageways are enclosed by a fixed top plate 41. Optionally, the top plate 41 can be configured to also cover the radial slots 35, the sample discs 1 and 17, or portions thereof.
As shown in FIG. 4, the whole blood sample disc 1, with capillaries 3 in place, is inserted into the hollow center 33 of the rotor, with each capillary 3 extending into a slot of the raised portion of the outer rotor body. The outer end of each capillary tube 3 is in direct communication with a passageway 39 leading to a cavity 37. The serum sample disc 17 with capillary tubes 19 in place is positioned directly above and mated to the whole blood sample disc by means of the center section 11 of the whole blood sample disc. As with the whole blood capillary tubes 3, the outer end of each capillary tube 19 is in direct communication with a separate passageway 39 leading to a cavity 37 at the outer periphery of the rotor body. The radial slots 35 ensure that each of the capillary tubes 3 are aligned with a capillary tube 19, each pair of tubes aligned with one of the passageways 39 and cavities 37. Alternative means for alignment can be provided, in which case the radial slots 35 can be eliminated.
Upon securement of both discs in the sample preparation rotor 29, the latter is rotated. Through centrifugal force the samples in the whole blood capillaries are drawn to the separate passageways 39 and into the cavities 37. The generated centrifugal force produces separation of the blood into serum and blood solids in the known manner, the solids in each blood sample migrating to the outermost peripheral portion of each cavity 37, resulting in a layer. The serum collects radially inward in the cavity. Upon effecting the desired separation, the rotor 29 is stopped with the top layers of serum being in contact with the capillary tubes 19 of the serum sample disc, and accordingly are drawn into the tubes by capillary action. The serum sample disc, complete with filled serum tubes, is then transferred to an analytical rotor.
An analytical rotor is shown in FIG. 5, and is indicated generally by the number 43. A circular rotor body 45 is fixed to a bottom cover (not shown). The rotor body is designed with a circular opening 47 at the center to accommodate the serum sample disc 17 (not shown). The rotor body 45 contains a plurality of equally spaced sample cuvettes 49 (four shown) located around the outer periphery 51 of the body. A cavity 53 for analyical reagents is located radially inward from each cuvette 49 and communicates with the cuvette by way of a small passageway 55. The cuvettes, cavities and reagent passageways are enclosed by a fixed top cover 57. A plurality of radial slots 59 are provided in the top cover and rotor body to accommodate the capillary tubes 19 (not shown) of the serum sample disc 17 (not shown). An opening 61 through the top cover is provided at each reagent cavity for filling of the reagent cavities 53. The outer terminus 63 of each slot 59 communicates with a separate cuvette 49 by way of a connecting passageway 65 in the rotor body.
In an alternative embodiment, reagent can be dispensed to the cuvettes via dynamic loading from a central location in the analytical rotor, rather than from individual reagent cavities. In dynamic loading, reagent is dispensed to the rotor while it is spinning and is distributed to each cuvette by centrifugal force. Generally, dynamic loading can be employed when only a single reagent is used for performing the same analysis on all the samples in the cuvettes. Where different analyses using different reagents on the samples are performed, static loading using separate reagent cavities as described above is preferred.
The analytical rotor is rotated at sufficient speed to cause the serum samples to be transferred by centrifugal force from the capillaries 19 through the connecting passageways 65 and into the cuvettes 49. Simultaneously, reagent from the reagent cavities 53 enters the cuvettes via passageways 55 and mixes with the samples. The cuvettes containing the individual samples and reagent can then be analyzed by conventional means.
The rotational speed required to produce the necessary centrifugal force in the sample preparation and analytical rotors is in part dependent on the diameter of the rotors, and those skilled in the art can readily ascertain the correct rotational speed for a given rotor diameter. Generally, rotational speeds can be varied from about 1000 to about 4000 rpm. Rotor diameters can vary upwards from a few centimeters. In a preferred embodiment, the rotors are about 8.7 cm in diameter. The capillary tubes can also vary in size depending on the rotor diameter. Whole blood capillaries of about 1 inch in length and with a capacity of from about 100 μl to about 200 μl are preferred. Serum capillaries are generally of a smaller diameter than whole blood capillaries. For example, a 1.000±0.002-in. length of precision bore tubing having an internal diameter of 0.0279±0.0005 in. can be used and will contain a volume of 10.0±0.4 μl of liquid. By using tubes of different internal diameters, various volumes of liquid may be obtained. Thus, the appropriate volume of serum sample required by a specific chemical assay may be obtained by selection and use of a 1-in. length of capillary of the appropriate internal diameter.
The invention is illustrated by the following example:
A whole blood sample (˜200 μl) was loaded by capillary action into each capillary of a whole blood sample disc. Sample identification was accomplished by omitting one capillary tube from the disc to form a blank site, and numbering the remaining tubes in numerical order beginning with No. 2. The experimental system contained 16 active sample sites. A loaded whole blood sample disc was positioned in the sample preparation rotor with the blank site thereof located at a blank site in the rotor, and with each loaded capillary tube located in a rotor slot in communication with a passageway leading to a sample cavity in the rotor. The empty serum sample disc with one capillary tube omitted was positioned on top of the sample preparation rotor. Using the blank sites as a guide, the serum sample disc was placed in the rotor resting on and mated with the whole blood sample disc with the outer ends of the empty capillary tubes in contact with the inner openings of the passageways leading to the sample cavities in the rotor. The rotor, with two discs in place, was then rotated at high speed (˜4000 rpm), the centrifugal force moving the whole blood sample from each capillary tube of the whole blood sample disc to the corresponding sample cavity in the rotor. High speed rotation was continued until the serum separated from the solids (red cells, platelets, etc.). The solids were contained in the outer portion of the cavity while the serum occupied the inner portion of the cavity and the passageway. The roor was then stopped and the serum from each active site on the rotor filled the corresponding capillary tube of the serum sample disc by capillary action. Thus, a known volume of serum from each blood sample was contained in a capillary tube of serum sample disc. Volumes of blood and serum samples could be varied by the use of capillary tubes with differing bore diameters.
The loaded serum sample disc was removed from the sample preparation rotor and placed in an analytical rotor which had the prescribed analytical reagents in the reagent cavities. The vacant site on the serum sample disc was situated in accord with a vacant site on the analytical rotor, and each loaded capillary tube was positioned into its respective slot with the outer end in direct communication with the passageway leading to a sample cuvette. The rotor was then rotated at 4000 rpm. The serum samples were moved by the centrifugal force from the capillary tubes through the passageways into the sample cuvettes. Simultaneously, the analytical reagents were moved from the reagent cavities through the connecting passageways to the sample cuvettes, where they mixed and reacted with the serum samples in preparation for analysis by conventional photometric methods.
The invention can be used in clinical laboratory blood analysis to extend and improve the capability of the some 40,000 centrifugal fast analyzers now in use. This system also has a potential for use in a zero-gravity environment. In addition, the system can be incorporated into a low-cost analytical system suitable for use in doctors' offices and other areas where high performance, economy and ease of operation are required.
The foregoing description of preferred embodiments has been set forth merely to illustrate the invention and is not intended to be limiting. Since modifications of the described embodiments incorporating the spirit and substance of the invention may occur to persons skilled in the art, the scope of the invention should be limited solely with respect to the appended claims and equivalents. | A rotor and disc assembly for use in a centrifugal fast analyzer. The assembly is designed to process multiple samples of whole blood followed by aliquoting of the resultant serum into precisely measured samples for subsequent chemical analysis. The assembly requires minimal operator involvement with no mechanical pipetting. The system comprises (1) a whole blood sample disc, (2) a serum sample disc, (3) a sample preparation rotor, and (4) an analytical rotor. The blood sample disc and serum sample disc are designed with a plurality of precision bore capillary tubes arranged in a spoked array. Samples of blood are loaded into the blood sample disc in capillary tubes filled by capillary action and centrifugally discharged into cavities of the sample preparation rotor where separation of serum and solids is accomplished. The serum is loaded into the capillaries of the serum sample disc by capillary action and subsequently centrifugally expelled into cuvettes of the analytical rotor for analysis by conventional methods. | 8 |
BACKGROUND OF THE INVENTION
[0001] The invention relates to a connector system with a connector, a fastening screw and an anchoring screw according to the precharacterizing clause of claim 1 and to a profile assembly.
[0002] DE 198 25 426 B4 and DE 199 25 993 A1 each disclose a fastening element for a proximity switch, which fastening element can be inserted into a T groove and can be brought into a clamping position with respect to the flanks of the T groove, but is not suitable as a fastening screw for a connector system of the type mentioned at the beginning. A connector as can customarily be used in profile assemblies is disclosed in U.S. Pat. No. 6,582,149 B1. Examples of profile assemblies are described, for example, in DE 202 03 283 U1 and U.S. Pat. No. 7,004,667 B2.
[0003] A connector system in which a connector is designed as a tensile connector is disclosed in DE 4127284 C1. A corresponding profile construction made of profile rods has at least in each case one longitudinal groove which is provided with at least one undercut, with at least some of the profile rods having at least one longitudinal bore which, at least at one of the ends thereof, has a thread which is provided for engagement with an anchoring screw. By means of the anchoring screw, a connector which is penetrated by the anchoring screw and has at least one limb can be fixed on the associated first profile rod which engages in such a manner in the longitudinal groove of the second profile rod to be connected that it engages by means of a limb behind at least one undercut. The connector can be fixed on the first profile rod with predefinable play and engages in the longitudinal groove of the second profile rod with at least partial compensation for said play. A fastening screw is received in a bore, which reaches completely through the connector and has an internal thread, and is supported with its one end against an anchoring screw such that the connector is pressed by means of at least one limb against a profile web of an undercut in such a manner that, by this means, the profile rods are connected fixedly to one another via the connector. The above-mentioned connector therefore imparts a pressing pressure which the fastening screw exerts on the head of the anchoring screw.
[0004] A tilting connector is disclosed in DE 20 2005 013 097.4 U1. Said tilting connector is suitable for fixing in a groove of a first profile, which groove is provided with an undercut, and is in the form of a connector body stretched along a longitudinal extent. The connector body has: a base and a web, which protrudes from the base and extends along the longitudinal extent, for laterally fixing the tilting connector in the groove, with a base region protruding from the web forming a stop surface for engagement behind the undercut, and a first hole being provided for an anchoring screw for introduction thereof into a second profile, and a second hole being provided for a fastening screw designed as a lever screw. The stop surface has a first stop region and a second stop region which are arranged at a releasing angle with respect to each other, thus forming a tilting edge which is located between them and which is provided for the contact and formation of a lever arrangement on a rear side of the undercut.
[0005] A connector system of the type mentioned at the beginning is disclosed in German utility model G 94 14 884.8.
[0006] Both connectors according to the prior art have a substantially angular three-dimensional shaping and generally have to be formed as comparatively costly precision castings.
[0007] It would be desirable to design a connection in a manner such that it can be produced at a comparatively more advantageous cost and nevertheless to ensure a secure connection in a profile assembly.
SUMMARY OF THE INVENTION
[0008] The object of the invention is to specify a connector system with a fastening screw and a connector which can be produced at a comparatively advantageous cost and nevertheless can provide a secure connection for a profile assembly. It is a further object to specify a corresponding profile assembly. The object is achieved by a connector system with the features of claim 1 and a profile assembly with the features of claim 25 .
[0009] In the case of the connector, the connector body extends according to the invention substantially flat along a connector body plane. The maximum thickness of the connector body preferably amounts to no more than 20% of a longitudinal extent of the connector body, i.e. the latter is a preferred, substantially flat connector body. In particular, the thickness is taken on over a substantial and in particular substantially planar region.
[0010] The invention has recognized that it is possible with the connector system according to the concept of the invention to produce the connector body at a comparatively advantageous cost in the form of a sheet-metal part and/or a punched part and/or a bent part. The substantial advantage is that a comparatively costly production of a connector body by precision casting can be omitted.
[0011] According to the invention, a flange which extends radially outward from a screw head is integrally formed on the fastening screw.
[0012] The invention has recognized that it is possible with a fastening screw designed in such a manner to support the flange on the undercut of the groove, which is formed by the profile web. When the fastening screw is tightened, the effect achieved owing to the external thread of the stem, which external thread is in engagement with the internal thread of the second opening of the connector body, is that the above-mentioned supporting effect is obtained on the flange bearing on that side of the undercut which faces the interior of the groove, and therefore the connector is moved further with respect to the interior of the groove in the direction of the groove base.
[0013] According to the invention, the connector system of the type mentioned at the beginning furthermore has an anchoring screw, with, according to the concept of the invention, the anchoring screw being provided for arrangement in the first opening of the connector, and at least one fastening screw being provided for arrangement in at least one second opening.
[0014] A movement of the connector guided toward the interior of the groove results in a tensile effect on the anchoring screw which is provided with a stem for fixing in a receiving opening, preferably in a central receiving opening of a second profile of a profile assembly. According to the concept of the invention, the effect thereby achieved is that the second profile, which generally stands perpendicularly on the first profile, is pulled onto the profile and, as a result, is fixed to the first profile.
[0015] Accordingly, the concept of the invention results in a profile assembly of the type mentioned at the beginning with a first profile having a groove provided with an undercut formed by a profile web, and with a second profile having a receiving opening and a connector system according to the concept of the invention. In this case, the first profile and the second profile can be of substantially identical design.
[0016] Advantageous developments of the invention can be gathered from the dependent claims and specify in detail advantageous possibilities of realizing the above-explained concept within the context of the object set and with regard to further advantages.
[0017] According to a particularly preferred development of the invention, the connector body has precisely one second opening provided with an internal thread and intended for a fastening screw. This is advantageously a low-weight connector body which can be formed in a particularly simple manner. With regard to the connector system, it is provided, according to this development, that precisely one fastening screw acts in the functional position as a lever screw, and the connector acts in the functional position as a tilting connector with a tilting edge on the far side of the first opening. In this development of the invention, upon rotation of the fastening screw, the connector body is pushed on the side opposite the tilting edge into the interior of the groove while the tilting edge bears against that surface of the undercut which faces the interior of the groove. It has proven particularly advantageous with regard to this development that an advantageous design of a lever arm such that it is matched to its use can be achieved by changing the length of the connector body or changing the hole spacing in the connector body. The lever effect is greater the further away the tilting edge is from the axis of the fastening screw. In practice, this enables one lever design which is suitable for any tightening torque to be provided.
[0018] The position of the fastening screw can also bring about a fixing of the perpendicular profile by the head diameter of the fastening screw and the width of the groove being matched to each other in such a manner that the head has comparatively little play in the groove. This has the advantage that the perpendicular profile is prevented from rotating, and the two profiles are arranged in a correct position with respect to each other, in particular without profile corners protruding.
[0019] According to a particularly preferred first variant of this development of the invention, the first opening for the anchoring screw is in the form of a thread-free screw hole—i.e. the hole edge completely surrounds the anchoring screw. The anchoring screw, for example additionally provided with a sleeve, can be fixed in a central receiving opening of the second profile by means of a threaded connection and can furthermore be held by means of its screw head in the first opening. As an alternative to the sleeve, the upper side of the connector body can have a collar on the first opening for the anchoring screw.
[0020] According to a second particularly preferred variant of this development, the first opening is in the form of a slot of the connector body, which slot runs in the longitudinal direction of the connector body and is delimited by fork-like arms. This has the advantage that the anchoring screw does not inevitably have to be placed into the first opening, but rather the second variant of this development makes it possible for the connector body, with the slot under a screw head of the anchoring screw, to be able to be pushed over the stem of the anchoring screw such that the head of the anchoring screw strikes behind the fork-like arms of the slot when the connector system is tightened. For this purpose, the head of the anchoring screw is preferably countersunk, in particular narrowed, toward the stem. By means of the latter measure, the slot can be pushed at a predefined position along the screw axis over the narrowing of the anchoring screw. The second variant of this development is very particularly suitable for use when placing a second profile into an existing profile assembly without profile connections which already exist having to be released, since, owing to its laterally open slot, the connector body can easily be pushed over the stem of the anchoring screw. The slot preferably has an indentation on its side facing the head of the anchoring screw. This has the advantage that the head is fixed particularly readily and at an early point to the connector body, in particular during the tightening of the fastening screw. For this purpose, the slot could also have, at its closed end, an expanded portion matched to the head of the anchoring screw.
[0021] According to a particularly preferred third variant of the invention, precisely two fastening screws are provided for arrangement in the precisely second openings, the two fastening screws each acting in the functional position as a tension screw, and the connector acting in the functional position as a tensile connector. The third variant of the invention permits particularly stable fixing of a second profile to a first profile by a respective fastening screw preferably on both sides of the central anchoring screw being tightened. As a result, the associated connector of the connector system is pushed forward at a parallel spacing from the profile web into the interior of the groove, and therefore the second profile, which stands perpendicularly on the first profile, is pulled toward the latter and fixed as a result.
[0022] Exemplary embodiments of the invention are now described below with reference to the drawing in comparison to the prior art, part of which is likewise illustrated. The drawing is not necessarily intended to illustrate the exemplary embodiments to scale; rather, the drawing is in schematized and/or slightly distorted form where this serves for explanation purposes. With regard to additions to the teaching which can be directly seen in the drawing, reference is made to the relevant prior art. In doing so, it should be taken into consideration that diverse modifications and changes relating to the shape and the detail of an embodiment can be undertaken without departing from the general concept of the invention. The features of the invention that are disclosed in the description, in the drawing and in the claims may be essential both individually and in any combination for the development of the invention. In addition, all combinations of at least two of the features disclosed in the description, the drawing and/or the claims are included in the scope of the invention. The general concept of the invention is not restricted to the exact form or the detail of the preferred embodiment shown and described below, or limited to a subject matter which would be restricted in comparison to the subject matter claimed in the claims. In the case of the stated dimensional ranges, values which lie within the above-mentioned limits are also intended to be disclosed as limit values and to be usable and claimable as desired.
BRIEF DESCRIPTION OF THE DRAWINGS
[0023] In the figures of the drawing, in detail:
[0024] FIG. 1 shows a sectional illustration of a profile assembly with a connector system as an embodiment according to the first variant of the invention;
[0025] FIG. 1A , FIG. 1B show a perspective illustration ( 1 A) and exploded illustration ( 1 B) of the preferred embodiment of the connector system from FIG. 1 ;
[0026] FIG. 2 shows a sectional illustration of a profile assembly with a connector system according to an embodiment according to the third variant of the invention;
[0027] FIG. 3A , FIG. 3B show a perspective illustration ( 3 A) and exploded illustration ( 3 B) of a connector system according to an embodiment according to the second variant of the invention, which connector system can furthermore be used—in a manner similar to that illustrated in FIG. 1 , FIG. 1A , FIG. 1 B—to assemble a profile assembly, but the connector system of this embodiment can also be pushed laterally over an anchoring screw.
DETAILED DESCRIPTION
[0028] FIG. 1 shows a profile assembly 10 with a connector 11 in an embodiment according to the first variant of the invention. The present profile assembly 10 has a first profile 1 and a second profile 2 which are of substantially identical design. In the case of the first profile 1 , the undercut 5 formed by a profile web 3 is shown, a groove 7 running between said undercut 5 and the groove base 9 , said groove having a narrow point between two opposite profile webs 3 (not shown specifically) and expanding toward the groove base 9 . The respective axes of symmetry of the profiles 1 and 2 are denoted by 4 and 6 .
[0029] The connector 11 has a connector body 13 which extends substantially flat along a connector body plane 15 indicated by dashed lines. In the present case, the maximum thickness D of the connector body 13 amounts to no more than 20% of a longitudinal extent L of the connector body 13 .
[0030] The connector system 12 , which is reproduced perspectively once again in FIG. 1A and FIG. 1B and comprises a connector 11 , fastening screw 17 and anchoring screw 19 , provides that, as illustrated in FIG. 1 , the anchoring screw 19 is provided for arrangement in the first opening 21 of the connector 11 , and precisely one fastening screw 17 is provided for arrangement in the second opening 23 of the connector 11 . At one end, the fastening screw 17 has a stem 27 bearing an external thread 25 , and a flange 29 which extends radially outward from a screw head 31 , in the present case in the form of a hexagon socket insert cup 33 . As a modification, other insert cups may be realized, for example a hexalobular internal insert cup.
[0031] The anchoring screw 19 is screwed into a central receiving opening 35 of the second profile 2 , which receiving opening runs along the axis 6 . Said anchoring screw is held by its countersunk head 37 , which in turn has a hexagon socket cup 39 , in a form-fitting manner without a thread in the precisely one second opening 21 of the connector body 13 . By contrast, the precisely one second opening 23 bears an internal thread 41 in which the external thread 25 of the stem 27 of the fastening screw 17 engages.
[0032] In the embodiment of a connector 11 that is illustrated in FIG. 1 , FIG. 1A and FIG. 1B , the connector body 13 is reinforced in the region of the first opening 21 and in the region of the second opening 23 by it in each case taking on a somewhat larger thickness over a substantial region. In the present case, this is realized in particular by the second opening 23 having a threaded collar 43 which, in this case, faces the groove base 9 . Similarly, the first opening 21 is reinforced in its side 45 facing the undercut 5 by means of a step-like thickened portion. In a modification thereto, a collar could also be integrally formed on the first opening 21 on the connector body 13 in addition to or as an alternative to the step.
[0033] Further reinforcements (not shown here) can be provided in embodiments in which the thickness D of the connector 11 could prove too little to withstand stressing during the formation of the profile assembly 10 . Thus, in other embodiments (not shown), in addition or as an alternative, one or more stiffening ribs running in particular along an elongate extent, and/or one or more, in particular lateral, webs running in particular along an elongate extent, can be provided. In the case of a punched and/or bent part in the form of sheet metal—as in the case of the present connector body 13 —such webs can preferably be formed as bent-up webs. As an addition or as an alternative, one or more beads or elongate knobs may be pressed into the connector body 13 .
[0034] In the case of further variants (not shown here) of the embodiment according to FIG. 1 , FIG. 1A and FIG. 1B , the thread axis 47 in the second opening 23 can also run obliquely with respect to a perpendicular to the connector body plane 15 . This increases the handling comfort when tightening the fastening screw 17 , since a hexagon key web in the hexagon key pin can more easily be inserted into the hexagon socket cup 33 . An obliquely positioned thread axis for the fastening screw 17 would advantageously also increase the fixing region of the fastening screw 17 in the groove of the perpendicular profile 2 . In addition, such a tilting connector would be more universally usable.
[0035] In the case of the embodiment illustrated in FIG. 1 , FIG. 1A and FIG. 1B , the fastening screw can be rotated in the normal direction of rotation by fitting a hexagon key in the hexagon socket cup 33 . For this purpose, in the present case, the internal thread 41 of the connector body 13 is designed as a left-handed thread with the external thread 25 of the stem 27 . In the embodiment illustrated in FIG. 1 , FIG. 1A and FIG. 1B , the threads 41 , 25 are designed as fine pitch threads with a pitch of 0.75 mm per turn, instead of normally with a pitch of 1.25 mm per turn. As a result, the fastening screw 17 can be tightened in a particularly smooth-running manner, with the connector body 11 being pressed by means of its side 53 opposite a tilting edge 51 away from the undercut 5 toward the interior 9 of the groove in accordance with the arrow depiction 49 in FIG. 1 . By means of the tilting 49 , tension is exerted on the anchoring screw 19 which—owing to being fixed in the receiving opening 35 of the upright second profile 2 —pulls the second profile 2 onto that surface of the first profile 1 which is formed by the profile web 3 , and fixes it there.
[0036] The tilting connector shown in FIG. 1 is part of a connector system shown in FIG. 1A and FIG. 1B , which part can be produced particularly easily and nevertheless ensures a secure profile assembly 10 . In order to place the connector 11 into the groove 7 , there is a slight degree of play between the connector body 13 and the profile web 3 so that the connector 11 can be pushed in and the described lever effect between the tilting edge 51 and that part 53 of the connector body 13 which executes the tilting movement 49 can come into action.
[0037] FIG. 2 shows a further preferred embodiment of a connector system in a profile assembly 20 in comparison to FIG. 1 . In the present case, the connector system has a connector 61 which has precisely two second openings 59 A, 59 B provided with an internal thread 57 A, 57 B. A respective fastening screw 17 , as has already been described with respect to FIG. 1 , engages in said openings. The same reference numbers are accordingly provided. In the present case, the first opening 63 is arranged centrally between the second openings 59 A, 59 B and in turn receives an anchoring screw 19 which has already been described with respect to FIG. 1 —and, in turn, the same reference numbers are provided for the anchoring screw 19 . In the present case, the connector body 65 of the connector 61 has, in the region of the first opening 63 , a means for securing against rotation—in the present case in the form of an angular elevation which forms the opening delimitation of the first opening 63 and via which the connector 61 can be fixed in the mutually facing end sides of the profile webs 3 at the narrowing of the groove. In addition, it is advantageous that, if the connector is preinstalled over the opening delimitation, a distance of the flat regions from the perpendicular profile 2 and therefore from an inner side of an undercut of the horizontal profile 1 is predefined.
[0038] When the two fastening screws 17 are tightened, the anchoring screw 19 is subjected on both sides to a tensile load via the connector 61 in the form of a tensile connector. The anchoring screw 19 is pulled into the groove 7 and, as a result, the perpendicular, second profile 2 is fixed to the first profile 1 .
[0039] FIG. 3A and FIG. 3B show a further embodiment of a connector system 72 in which the fastening screw 18 acts as a lever screw and the connector 61 acts as a tilting connector with a tilting edge 51 ′ on the far side of the first opening 21 ′—in a very similar manner to that shown in FIG. 1 . Accordingly, the same reference numbers have been provided for mutually corresponding parts of the figure.
[0040] In contrast to the connector 11 shown in FIG. 1 , the connector 71 of FIG. 3A , FIG. 3B is provided with a first opening 21 ′, which is in the form of a slot of the connector body 73 , which slot runs in the longitudinal direction of the connector body 73 and is delimited by fork-like arms 75 . In the present case, the fork-like arms 75 have an end-side widened portion 77 which runs transversely with respect to the longitudinal direction of the connector body and serves to extend a tilting edge 51 ′ and therefore to improve the tilting behavior of the connector 71 . As a result, the tilting connector is also stabilized in its position. The widened portion 77 may, if appropriate, also be designed in such a manner that it counteracts an expansion of the fork-like arms 75 by bearing on an outer side against an inner side of the groove.
[0041] The fastening screw 18 provided for this purpose again has a flange 28 which, in the present case, has two opposite interruptions 26 along its circumference, with, in the region of said interruption, the screw head being the same size as the hexagon socket insert cup. In a particularly preferred manner, the flange 28 in the present case has a ramp 24 provided with a slope. The ramp 24 can be provided on its upper side with a structure, for example with a ribbing or with latching teeth, which counteracts a release of the screw. In the present case, the slope of the ramp 24 is such that, upon a quarter turn of the fastening screw 18 , a profile assembly is closed such that the present case involves a ramp 24 with a quarter turn slope. This measure advantageously ensures that, above a quarter turn, over-rotation of the fastening screw 18 and therefore slipping of the fastening screw 18 out of a groove 7 are avoided. For this purpose, a ramp can advantageously have, at its upper end, an additional raised portion acting as a stop. In principle, a fastening screw with a ramp, for example the fastening screw 18 or a modification thereof, for example modified in relation to the interruptions 26 or the slope of the ramp 24 , can be used in all of the above-mentioned embodiments of a connector 11 , 61 , 71 .
[0042] The connector 71 according to FIG. 3A , FIG. 3B can be used in a particularly simple manner in order to connect a second profile 2 retrospectively to a first profile 1 —i.e. between two perpendicular profiles which are already present. For this purpose, the second profile 2 is placed onto the first profile 1 by means of an anchoring screw 19 such that the anchoring screw projects into the groove 7 of the first profile 1 . The connector 71 is subsequently pushed laterally into the groove and such that it engages with its fork-like arms in the narrowing and around the anchoring screw 19 between the countersunk screw head 37 and the thread M 8 . The connector system can subsequently be tightened, as already described with reference to FIG. 1 , FIG. 1A and FIG. 1B in order to connect the first profile 1 and the second profile 2 to each other.
[0043] In summary, a connector 11 , 61 , 71 is provided for fixing in a groove 7 of a first profile 1 , which groove is provided with an undercut 5 formed by a profile web 3 , with a connector body 13 , 65 , 75 which has: a first opening 21 , 63 , 21 ′ for an anchoring screw 19 and at least one second opening 23 , 23 ′, 59 A, 59 B provided with an internal thread 41 , 57 A, 57 B and intended for a fastening screw 17 , 18 . According to the concept of the invention, the connector body 13 , 65 , 75 extends substantially flat along a connector body plane 15 . The maximum thickness D of the connector body 13 , 65 , 75 , taken on in particular over a substantial region, preferably amounts to no more than 20% of a longitudinal extent L of the connector body 13 , 65 , 75 . This has the advantage that the connector body 13 , 65 , 75 can be in the form of a sheet-metal part and/or a punched and/or bent part. A fastening screw 17 , 18 provided for forming a connector system at one end has a stem 27 bearing an external thread 25 . According to the invention, a flange 29 is integrally formed, said flange extending radially outward from a screw head 31 . The flange 29 is supported against the profile web 3 of the first profile 1 upon rotation of the fastening screw 17 , 18 in the internal thread 41 of the connector 11 , 61 , 71 . According to the concept of the invention, the connector system 11 , 61 , 71 additionally provides an anchoring screw 19 . According to a first variant of the invention, the connector 11 is designed as a tilting connector, with the first opening being in the form of a thread-free screw hole. According to a second variant of the invention, the connector 71 is formed as a tilting connector, with the first opening 21 being in the form of a slot of the connector body 73 , which slot runs in the longitudinal direction of the connector body and is delimited by fork-like arms 75 . According to a third variant of the invention, the connector 61 is designed as a tensile connector. | A connector system ( 12,72 ) with a connector ( 11,61,71 ) of a fastening screw ( 17,18 ) and an anchor screw ( 19 ), wherein the connector ( 11, 61, 71 ) is designed for immobilization in a groove ( 7 ) of a first profile ( 1 ) which is provided with an undercut ( 5 ) formed by a profile bridge ( 3 ) and has a connector body ( 13, 65, 75 ) which has a first opening ( 21, 63, 31′ ) for an anchor screw ( 19 ) and at least one second opening ( 23, 23′, 59 A, 59 B) which is provided with an internal thread ( 41 ) and intended for a fastening screw ( 17, 18 ). The connector body ( 13, 65, 75 ) extends substantially flat along a connector body plane ( 15 ), and the fastening screw ( 17, 18 ) at one end has a shaft ( 27 ) carrying an external thread ( 25 ) and an integrally molded flange ( 28, 29 ) which extends radially to the outside from a screw head ( 31 ), wherein the anchor screw ( 19 ) is provided for placement in the first opening ( 21, 21′, 63 ) of the connector ( 11, 61, 71 ), and at least one fastening screw ( 17, 18 ) is provided for placement in the at least one second opening ( 23, 59 A, 59 B). | 8 |
BACKGROUND OF THE INVENTION
Inhibitors of 11β-Hydroxysteroid Dehydrogenase Type 1 (11β-HSD1) are promising drugs for the treatment of a number of diseases and disorders as described in detail in U.S. Provisional Patent Application No. 60/962,058, filed Jul. 26, 2007; U.S. Provisional Patent Application No. 61/001,253, filed Oct. 31, 2007; U.S. Provisional Patent Application No. 61/049,650, filed May 1, 2008; and International Application No. PCT/US2008/009017 all of which are herein incorporated by reference in their entirety.
For example, 11β-HSD1 inhibitors are promising for the treatment of diabetes, metabolic syndrome, obesity, glucose intolerance, insulin resistance, hyperglycemia, hypertension, hypertension-related cardiovascular disorders, hyperlipidemia, deleterious gluco-corticoid effects on neuronal function (e.g. cognitive impairment, dementia, and/or depression), elevated intra-ocular pressure, various forms of bone disease (e.g., osteoporosis), tuberculosis, leprosy (Hansen's disease), psoriasis, and impaired wound healing (e.g., in patients that exhibit impaired glucose tolerance and/or type 2 diabetes).
There is a need for better, for example, more economical and more efficient methods for synthesis of the 11β-HSD1 inhibitors.
SUMMARY OF THE INVENTION
The present invention provides economical and efficient methods for the synthesis of 11β-HSD1 inhibitors, for example, oxazinone compounds and tertiary alcohol oxazinone compounds as disclosed herein.
One embodiment of the present invention is a method of preparing an oxazinone compound represented by structural formula (I):
R 1 is (a) absent or (b) is selected from optionally substituted (C 1 -C 6 )alkyl, optionally substituted (C 2 -C 6 )alkenyl, optionally substituted (C 2 -C 6 )alkynyl, optionally substituted (C 1 -C 3 )alkoxy(C 1 -C 3 )alkoxy, and optionally substituted (C 1 -C 3 )alkoxy(C 1 -C 3 )alkyl;
E is (a) a bond or (b) (C 1 -C 3 )alkylene or (C 1 -C 2 )alkoxy, wherein the O is attached to R 2 , each of which is optionally substituted with 1 to 4 groups independently selected from methyl, ethyl, trifluoromethyl and oxo;
R 2 is selected from optionally substituted (C 1 -C 6 )alkyl, optionally substituted aryl, optionally substituted heteroaryl, optionally substituted cycloalkyl or optionally substituted heterocyclyl;
R 3 is selected from optionally substituted (C 1 -C 6 )alkyl, optionally substituted (C 2 -C 6 )alkenyl, optionally substituted (C 2 -C 6 )alkynyl, optionally substituted (C 3 -C 5 )cycloalkyl(C 1 -C 4 )alkyl, optionally substituted (C 1 -C 3 )alkoxy(C 1 -C 3 )alkoxy and optionally substituted (C 1 -C 3 )alkoxy(C 1 -C 3 )alkyl;
A 1 is (a) a bond, or (b) (C 1 -C 3 )alkylene, CH 2 CH 2 O, wherein the oxygen is attached to Cy 1 ;
Cy 1 is optionally substituted aryl, optionally substituted heteroaryl, optionally substituted monocyclic cycloalkyl or optionally substituted monocyclic heterocyclyl;
A 2 is (a) a bond, O, S or NR 4 , wherein R 4 is (C 1 -C 3 )alkyl or (C 3 -C 6 )cycloalkyl; or (b) (C 1 -C 3 )alkylene or (C 1 -C 2 )alkoxy, each of which is optionally substituted with 1 to 4 groups independently selected from methyl, ethyl, or trifluoromethyl.
Cy 2 is (a) hydrogen or (b) optionally substituted aryl, optionally substituted heteroaryl, optionally substituted cycloalkyl or optionally substituted heterocyclyl.
The method comprises the step of reacting a β-haolalcohol compound, for example a β-haloalcohol compound represented by structural formula (II)
with an isocyanate compound represented by structural formula (III)
X is a leaving group
Another embodiment of the present invention is a method of preparing an epoxide compound represented by structural formula (IV):
The method comprises the step of oxidizing with an epoxidation reagent a 2-methyl-3-propenyl intermediate represented by the following structural formula:
A 1 , A 2 , Cy 1 , Cy 2 , R 1 , R 2 and E in structural formulas (IV) and (V) are as defined in structural formula (I).
Another embodiment of the present invention is a method of preparing tertiary alcohol oxazinone compound represented by structural formula (VI):
The method comprises the step of reducing the epoxide group of the epoxide compound represented by structural formula (IV) with a reducing agent. A 1 , A 2 , Cy 1 , Cy 2 , R 1 , R 2 and E in structural formula (VI) are as defined in structural formula (V).
In an alternative embodiment, the tertiary alcohol oxazinone compound represented by structural formula (VI) can be prepared using the compound of structural formula VII:
following the synthetic scheme set forth in FIG. 2 . Example 22 provides details of the synthetic steps of FIG. 2 for the preparation of (S)-3-((S)-1-(4-bromophenyl) ethyl)-6-(2-hydroxy-2-methylpropyl)-6-phenyl-1,3-oxazinan-2-one.
A 1 , A 2 , Cy 1 , Cy 2 , R 1 , R 2 and E in structural formula (VII) are as defined in structural formula (I).
Another embodiment of the present invention is an epoxide compound represented by structural formula (IV) or a salt thereof.
Yet another embodiment of the present invention is a 2-methyl-3-propenyl intermediate represented by structural formula (V) or a salt thereof.
Other embodiments of the present invention are the epoxide compounds and salts thereof, and 2-methyl-3-propenyl intermediates and salts thereof as prepared with the methods of the present invention, in particular, the epoxide compounds and 2-methyl-3-propenyl intermediates corresponding to the above described embodiments.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic, showing the synthesis of a specific tertiary alcohol oxazinone compound, a 11β-HSD1 inhibitor, using the methods disclosed herein.
FIG. 2 is a schematic, showing the synthesis of a specific tertiary alcohol oxazinone compound, a 11β-HSD1 inhibitor, using the methods disclosed herein.
DETAILED DESCRIPTION OF THE INVENTION
The present invention provides methods for synthesizing 11β-HSD1 inhibitors, for example, oxazinone compounds and tertiary alcohol oxazinone compounds as disclosed herein.
The oxazinone compound represented by structural formula (I), for example, compounds 5 and 6 (see Figure), can be prepared by reacting a β-haloalcohol compound represented by structural formula (II) with an isocyanate compound represented by structural formula (III). Both, the β-haloalcohol compound and the isocyanate compound can be prepared from commercially available compounds using methods known in the art (see, Exemplification section).
The tertiary alcohol oxazinone compound represented by structural formula (VI) such as, for example, compound 8 (see FIG. 1 ) is prepared by first oxidizing 2-methyl-3-propenyl intermediate represented by structural formula (V) with an epoxidation reagent to obtain the epoxide compound represented by structural formula (IV). The 2-methyl-3-propenyl intermediate is an oxazinone compound that can be prepared using the method described in the previous paragraph, wherein R 3 is 2-methyl-3-propenyl. In a second step, the epoxide group of the epoxide compound is reduced with a reducing agent to form the tertiary alcohol oxazinone compound.
Oxazinone compounds and tertiary alcohol oxazinone compounds represented by structural formulas (I) and (VI), respectively, for which Cy 1 is phenyl substituted with a leaving group (e.g., —Br) and optionally substituted with one or more additional substituents, can be used to prepare biaryl group containing 11β-HSD1 inhibitors, for example, by using a “Suzuki” coupling reaction as described in Example 111 of U.S. Provisional Patent Application No. 60/962,058, filed Jul. 26, 2007. Alternatively, oxazinone compounds represented by structural formulas (I) and (VI), respectively, for which Cy 1 is phenyl substituted with a leaving group (e.g., —Br) and optionally substituted with one or more additional substituents, can be used to prepare biaryl group containing 11β-HSD1 inhibitors, by conversion of the leaving group (e.g. —Br) to a boronic acid or boronate ester, followed by using a “Suzuki” coupling reaction with Cy 2 -Cl or Cy 2 -Br (see EXAMPLE 23). Alternatively, biaryl group containing 11β-HSD1 inhibitors can be obtained from isocyanate compounds that already contain the biaryl group using the methods of the present invention. The synthesis of a variety of biaryl compounds is provided in the Exemplification section.
A detailed description of each reaction in the syntheses is provided below. In the discussion below, A 1 , A 2 , Cy 1 , Cy 2 , R 1 , R 2 and E have the meanings indicated above unless otherwise noted. In cases where the synthetic intermediates and final products described below contain potentially reactive functional groups, for example amino, hydroxyl, thiol, sulfonamide, amide and carboxylic acid groups, that may interfere with the desired reaction, it may be advantageous to employ protected forms of the intermediate. Methods for the selection, introduction and subsequent removal of protecting groups are well known to those skilled in the art. (T. W. Greene and P. G. M. Wuts “Protective Groups in Organic Synthesis” John Wiley & Sons, Inc., New York 2007, herein incorporated by reference in its entirety). Such protecting group manipulations are assumed in the discussion below and not described explicitly. The term “protected” as used herein in combination with terms denoting chemical groups, for example, protected piperidinyl, refers to the chemical group with its functional groups that may interfere with a desired reaction having been reacted with a protective group, e.g., the ring nitrogen atom in the case piperidine.
Oxazinone Compounds
The oxazinone compound represented by structural formula (I) is prepared by reacting a β-haloalcohol compound represented by structural formula (II) with an isocyanate compound represented by structural formula (III) as shown above. Typically, the reaction of the a β-haloalcohol with the isocyanate compound is carried out in the presence of a base. More typically, the reaction is carried out in the presence of a non-nucleophilic base. Most typically, the reaction is carried out in the presence of a non-nucleophilic amine base. Suitable non-nucleophilic amide bases include, but are not limited to as lithium amide (LiNH 2 ), sodium amide (NaNH 2 ), lithium dimethylamide, lithium diethylamide, lithium diisopropylamide, lithium dicyclohexylamide, silicon-based amides, such as sodium and potassium bis(trimethylsilyl)amide, lithium tetramethylpiperidide, and lithium tetramethylpiperidine. Other non-nucleophilic bases include but are not limited to sodium hydride, sodium tert-pentoxide and sodium tert-butoxide. Examples of suitable non-nucleophilic amine bases include, but are not limited to, diisopropylethylamine, 2,2,6,6-tetramethylpiperidine, 4-dimethylaminopyridine, 2,6-di-tert-butyl-4-methylpyridine, 1,5-diazabicyclo[4.3.0]non-5-ene (DBN), 1,4-diazabicyclo[2.2.2]octane (DABCO), 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU), 2,8,9-trimethyl-2,5,8,9-tetraaza-1-phosphabicyclo[3.3.3]undecane and the like. Most typically, the base is 1,8-diazabicyclo[5.4.0]undec-7-ene. Although an excess of either β-haloalcohol compound or isocyanate compound can be used, the isocyanate compound is more commonly used in excess. Typically, from about one to about ten equivalents of base relative to β-haloalcohol are used, more typically from about one to about six equivalents, and, even more typically, from one to about 5 equivalents. Typically the reaction is carried out in an anhydrous aprotic, non-nucleophilic solvent at β-haloalcohol compound concentrations between about 0.01 M and 5 M. β-Haloalcohol compound concentrations are more typically, however, between about 0.05 M and 2 M. Suitable solvents include, but are not limited to ethereal solvents such as diethyl ether, tetrahydrofuran (THF), tert-butyl-methyl ether and 1,4-dioxane, and non-ethereal solvents such as dimethyl formamide and dimethyl sulfoxide and the like. Suitable reaction temperatures generally range from about 0° C. to about the boiling point of the solvent. More typically, temperatures are sufficiently high to allow refluxing, for example, about 68° C. for tetrahydrofuran.
Epoxide Compounds
The epoxide compound represented by structural formula (IV) is prepared by oxidizing the propenyl group of the 2-methyl-3-propenyl intermediate represented by structural formula (V) with an epoxidation reagent. The 2-methyl-3-propenyl intermediate is an oxazinone compound that can be prepared using the method described in the previous paragraphs (e.g., the reaction of a compound of Formula II with a compound of Formula III). Suitable epoxidation reagents include, but are not limited to peroxides (e.g., hydrogen peroxide, t-butyl hydroperoxide), peroxycarboxylic acids (e.g., 3-chloroperbenzoic acid (MCPBA), peracetic acid, pertrifluoroacetic acid), magnesium bis(monoperoxyphthalate) hexahydrate, potassium monoperoxysulfate optionally in the presence of 1,2:4,5-di-O-isopropylidene-β-D-erythro-2,3-hexodiulo-2,6-pyranose, dimethyldioxirane and the like. Typically, the epoxidation reagent is a peroxycarboxylic acid, and, most typically, it is 3-chloroperbenzoic acid. Typically, from about one to about ten equivalents of epoxidation reagent relative to 2-methyl-3-propenyl intermediate are used, more typically from about one to about six equivalents, and, most typically, from about one to about 2 equivalents. Typically the reaction is carried out in an aprotic, non-nucleophilic solvent at 2-methyl-3-propenyl intermediate concentrations between about 0.01 M and 5 M. 2-Methyl-3-propenyl intermediate concentrations are more typically, however, between about 0.05 M and 2 M. Suitable solvents include, but are not limited to, halogenated solvents (e.g., chloroform, dichloromethane and 1,2-dichloroethane, acetonitrile, dimethylformamide (DMF), dimethylacetamide (DMA), or hexamethylphosphorus triamide and ethereal solvents such as diethyl ether, tetrahydrofuran (THF) and 1,4-dioxane. Typically, the solvent is a halogenated solvent. More typically, the solvent is dichloromethane or 1,2-dichloroethane. Most typically, the solvent is dichloromethane. Suitable reaction temperatures generally range from about 0° C. to about the boiling point of the solvent used. Most typically, the reaction is carried out at ambient temperature.
Tertiary Alcohol Oxazinone Compounds
The tertiary alcohol oxazinone compound represented by structural formula (VI) is prepared by reducing the epoxide group of the epoxide compound represented by structural formula (IV) with a reducing agent. Suitable reducing agents include, but are not limited to hydride reducing agents such as lithium triethylborohydride, LiAlH 4 , LiBH 4 , lithium tri-t-butoxyaluminum hydride in the presence of triethylborane, potassium tri-sec-butylborohydride or sodium bis(2-methoxyethoxy)aluminum hydride and the like. Other suitable reducing agents include, but are not limited to BH 3 .Et 3 N—LiClO 4 , lithium di-tert-butylbiphenyl, or hydrogen or sodium formate in the presence of palladium on charcoal. Most typically, the reducing agent is lithium triethylborohydride (super hydride). Typically, from about one to about ten equivalents of reducing agent relative to the epoxide compound are used, more typically from about one to about six equivalents, and, most typically, from about one to about 2 equivalents. Typically the reaction is carried out in an anhydrous aprotic, non-nucleophilic solvent at epoxide compound concentrations between about 0.01 M and 5 M. Epoxide compound concentrations are more typically, however, between about 0.05 M and 2 M. Suitable solvents include, but are not limited to ethereal solvents such as diethyl ether, tetrahydrofuran (THF), tert-butyl-methyl ether and 1,4-dioxane, and non-ethereal solvents such as dimethyl formamide and dimethyl sulfoxide and the like. Typically, the solvent is an ethereal solvent. Most typically, the solvent is anhydrous tetrahydrofuran. Suitable reaction temperatures generally range from about 0° C. to about ambient temperature.
The processes for preparing the oxazinone compound represented by structural formula (I), the epoxide compound represented by structural formula (IV) and the tertiary alcohol oxazinone compound represented by structural formula (VI) as described in the previous three paragraphs and for the compounds represented by structural formulas (I), (IV), (V), (VI) and (VII) can further be described according to the following preferred embodiments. Note that R 3 and X refer to the preparation of an oxazinone compound only.
In a first preferred embodiment, Cy 1 , Cy 2 , R 2 , R 3 and X are as defined in structural formulas (I) to (VI) (see summary of invention) and R 1 is absent or is (C 1 -C 6 )alkyl; A 1 is a bond, CH 2 , or CH 2 CH 2 , or CH when R 1 is present; A 2 is a bond, O, OCH 2 CO or CH 2 ; X is a Cl, Br, I or —OSO 2 R, wherein R is (C 1 -C 4 )alkyl optionally substituted with one or more F, or phenyl optionally substituted with halogen, (C 1 -C 4 )alkyl or NO 2 ; and E is a bond or (C 1 -C 3 )alkylene.
In a second preferred embodiment, R 1 , R 2 , R 3 , X and E are as defined in the first preferred embodiment and A 1 is a bond or CH when R 1 is present; A 2 is a bond; Cy is hydrogen; Cy 1 is phenyl substituted with Cl, Br, I or OSO 2 CF 3 , and optionally substituted with one or more additional substituents.
In a third preferred embodiment, A 2 , Cy 2 , R 1 , R 2 , R 3 , X and E are as defined in the second preferred embodiment and A 1 is —CH, R 1 is present and Cy 1 is represented by the following structural formula:
Z is a Cl, Br, I, OSO 2 CF 3 , OSO 2 Me, or OSO 2 C 6 H 4 Me, r is 0, 1, 2 or 3; and each G 1 is independently selected from the group consisting of (C 1 -C 4 )alkyl, halo(C 1 -C 4 ) alkyl, (C 1 -C 4 )alkoxy, halogen, cyano and nitro.
In a fourth preferred embodiment, A 1 , A 2 , Cy 1 , Cy 2 , R 2 , R 3 , X, E, r, G 1 and Z are defined as in the third preferred embodiment and R 1 is methyl or ethyl.
In a fifth preferred embodiment, A 1 , A 2 , Cy 1 , Cy 2 , R 1 , X, E, r, G 1 and Z are defined as in the fourth preferred embodiment and R 2 is phenyl, thienyl, or pyridyl, each optionally substituted with halogen, nitro, cyano, (C 1 -C 6 )alkyl, protected hydroxy(C 1 -C 3 )alkyl, (C 1 -C 3 )alkoxy, protected CONH 2 , protected carboxylic acid and SO 2 Me; and with regard to the preparation of an oxazinone compound, R 3 is methyl, ethyl, propyl, butyl, vinyl, allyl, 2-methyl-3-propenyl, or ethoxyethyl, each optionally substituted with up to two groups independently selected from (C 1 -C 4 )alkyl, (C 1 -C 4 )alkoxy, (C 1 -C 4 )alkoxycarbonyl, benzyloxycarbonyl, protected hydroxy(C 1 -C 4 )alkyl, cyano(C 1 -C 4 )alkyl, protected (C 1 -C 4 )alkylamino, di(C 1 -C 4 )alkylamino, halogen, cyano, oxo, nitro, protected hydroxy, protected amino, MeSO 2 —, MeSO 2 N(Me)(C 1 -C 4 )alkyl, protected MeSO 2 NH(C 1 -C 4 )alkyl, protected H 2 NC(═O)CMe 2 (C 1 -C 4 )alkyl, protected H 2 NC(═O)CHMe(C 1 -C 4 )alkyl and protected H 2 NC(═O)CH 2 (C 1 -C 4 )alkyl.
In a sixth preferred embodiment, A 1 , A 2 , Cy 1 , Cy 2 , R 1 , R 2 , X, E, r, G 1 and Z are defined as in the fifth preferred embodiment and, with regard to the preparation of an oxazinone compound, R 3 is vinyl, allyl, 2-methyl-3-propenyl, MeSO 2 NHCH 2 CH 2 CH 2 , protected H 2 NC(═O)CH 2 CH 2 , protected H 2 NC(═O)CMe 2 CH 2 , 2-cyano-2-methylpropyl, 2-oxopropyl or (C 1 -C 4 )alkoxycarbonylmethyl.
In a seventh preferred embodiment, A 1 , A 2 , Cy 1 , Cy 2 , R 1 , R 3 , X, E, r, G 1 and Z are defined as in the sixths preferred embodiment and R 2 is phenyl optionally substituted with 1, 2 or 3 substituents selected from halo, cyano, protected CONH 2 , (C 1 -C 4 )alkyl, (C 1 -C 4 )alkoxy and SO 2 Me.
In an eight preferred embodiment, A 1 , A 2 , Cy 1 , Cy 2 , R 1 , R 2 , X, E, r, G 1 and Z are defined as in the seventh preferred embodiment and, with regard to the preparation of an oxazinone compound, R 3 is allyl, 2-methyl-3-propenyl, protected H 2 NC(═O)CMe 2 CH 2 or 2-cyano-2-methylpropyl.
In a ninth preferred embodiment, A 1 , A 2 , Cy 1 , Cy 2 , R 1 , R 2 , X, E, r, G 1 and Z are defined as in the seventh preferred embodiment and, with regard to the preparation of an oxazinone compound, R 3 is 2-methyl-3-propenyl or 2-cyano-2-methylpropyl.
In a tenth preferred embodiment, A 1 , A 2 , Cy 1 , Cy 2 , R 1 , R 3 , X, E, r, G 1 and Z are defined as in the ninth preferred embodiment and R 2 is phenyl or fluorophenyl.
In an eleventh preferred embodiment, A 1 , A 2 , R 1 , R 2 , R 3 , X and E are defined as in the first preferred embodiment and Cy 1 is phenyl, cyclopropyl, cyclohexyl, pyrrolidinyl, piperidinyl, azepanyl, pyridyl, thiazolyl, pyrimidinyl, each optionally substituted with 1 to 4 groups; and Cy 2 is phenyl, thienyl, pyridyl, cyclopropyl, piperidinyl, piperazinyl, morpholinyl, thiazolyl, oxadiazolyl, thiadiazolyl, pyrazolyl, S,S-dioxothiazinyl, pyridazinyl, pyrimidinyl, pyrazinyl, benzimidazolyl, benztriazolyl, oxodihydropyridyl, oxodihydropyridazinyl, oxodihydropyrimidinyl and oxodihydropyrazinyl, each optionally substituted by 1 to 4 groups; wherein substituents for a ring carbon atom of Cy 1 and Cy 2 are independently selected from halogen, cyano, oxo, nitro, protected hydroxy, protected amino, (C 1 -C 4 )alkyl, (C 3 -C 4 )cycloalkyl, (C 3 -C 4 )cycloalkyl(C 1 -C 2 )alkyl, (C 1 -C 4 )alkoxy, (C 11 -C 4 )alkoxycarbonyl, benzoxycarbonyl, protected CONH 2 , protected (C 1 -C 4 )alkylaminocarbonyl, di(C 1 -C 4 )alkylaminocarbonyl, protected (C 3 -C 4 )cycloalkylaminocarbonyl, {(C 1 -C 4 )alkyl}{(C 3 -C 4 )cycloalkyl}aminocarbonyl and protected (C 1 -C 4 )alkylcarbonylamino, wherein suitable substituents for a substitutable ring nitrogen atom in Cy 2 are selected from the group consisting of (C 1 -C 4 )alkyl, (C 3 -C 4 )cycloalkyl, (C 3 -C 4 )cycloalkyl(C 1 -C 2 )alkyl, (C 1 -C 4 )alkoxycarbonyl, (C 1 -C 4 )alkylcarbonyl and benzyloxycarbonyl. For the process of preparing an oxazinone compound, each substitutable ring nitrogen atom of Cy 2 , if present, is either bonded to A 2 , protected or substituted.
In a twelfth preferred embodiment, A 1 , A 2 , Cy 1 , Cy 2 , R 2 , R 3 , X and E are defined as in the eleventh preferred embodiment and R 1 is methyl or ethyl.
In a thirteenth preferred embodiment, A 1 , A 2 , Cy 1 , Cy 2 , R 1 , X and E are defined as in the twelfth preferred embodiment and R 2 is phenyl, thienyl, or pyridyl, each optionally substituted with halogen, nitro, cyano, (C 1 -C 6 )alkyl, protected hydroxy(C 1 -C 3 )alkyl, (C 1 -C 3 )alkoxy, protected CONH 2 , protected carboxylic acid and SO 2 Me; and, with regard to the preparation of an oxazinone compound, R 3 is methyl, ethyl, propyl, butyl, vinyl, allyl, 2-methyl-3-propenyl, or ethoxyethyl each optionally substituted with up to two groups independently selected from (C 1 -C 4 )alkyl, (C 1 -C 4 )alkoxy, (C 1 -C 4 )alkoxycarbonyl, benzyloxycarbonyl, protected hydroxy(C 1 -C 4 )alkyl, cyano(C 1 -C 4 )alkyl, protected (C 1 -C 4 )alkylamino, di(C 1 -C 4 )alkylamino, halogen, cyano, oxo, nitro, protected hydroxy, protected amino, MeSO 2 —, MeSO 2 N(Me)(C 1 -C 4 )alkyl, protected MeSO 2 NH(C 1 -C 4 )alkyl, protected H 2 NC(═O)CMe 2 (C 1 -C 4 )alkyl, protected H 2 NC(═O)CHMe(C 1 -C 4 )alkyl and protected H 2 NC(═O)CH 2 (C 1 -C 4 )alkyl.
In a fourteenth preferred embodiment, A 1 , A 2 , Cy 1 , R 1 , R 2 , R 3 , X and E are defined as in the thirteenth preferred embodiment and Cy 2 is optionally substituted and selected from the group consisting of benzimidazolyl, benzotriazolyl, oxodihydropyridyl, oxodihydropyridazinyl, oxodihydropyrimidinyl, oxodihydropyrazinyl, piperidinyl, pyridinyl, pyridazinyl, pyrimidinyl, pyrazinyl, pyrazolyl, thiazolyl and thiadiazolyl.
In a fifteenth preferred embodiment, A 1 , A 2 , Cy 1 , Cy 2 , R 1 , R 2 , X and E are defined as in the fourteenth preferred embodiment and, with regard to the preparation of an oxazinone compound, R 3 is vinyl, allyl, 3-propenyl-2-methyl, MeSO 2 NHCH 2 CH 2 CH 2 , protected H 2 NC(═O)CH 2 CH 2 , protected H 2 NC(═O)CMe 2 CH 2 , 2-cyano-2-methylpropyl, 2-oxopropyl or (C 1 -C 4 )alkoxycarbonylmethyl.
In a sixteenth preferred embodiment, A 1 , A 2 , Cy 1 , Cy 2 , R 1 , R 3 , X and E are defined as in the fifteenth preferred embodiment and R 2 is phenyl optionally substituted with 1, 2 or 3 substituents selected from halo, cyano, protected CONH 2 , (C 1 -C 4 )alkyl, (C 1 -C 4 )alkoxy and SO 2 Me.
In a seventeenth preferred embodiment, A 1 , A 2 , Cy 1 , Cy 2 , R 1 , R 2 , X and E are defined as in the sixteenth preferred embodiment and with regard to the preparation of an oxazinone compound, R 3 is allyl, 3-propenyl-2-methyl, protected H 2 NC(═O)CMe 2 CH 2 or 2-cyano-2-methylpropyl.
In an eighteenth preferred embodiment, A 1 , A 2 , Cy 1 , Cy 2 , R 1 , R 2 , X and E are defined as in the seventeenth preferred embodiment and, with regard to the preparation of an oxazinone compound, R 3 is 3-propenyl-2-methyl, or 2-cyano-2-methylpropyl.
In a nineteenth preferred embodiment, A 1 , A 2 , Cy 1 , Cy 2 , R 1 , R 3 , X and E are defined as in the eighteenth preferred embodiment and R 2 is phenyl or fluorophenyl.
In a twentieth preferred embodiment, A 1 , A 2 , Cy 1 , Cy 2 , R 1 , R 2 , R 3 , X and E are defined as in the nineteenth preferred embodiment and suitable substituents for a substitutable ring nitrogen atom in the group represented by Cy 2 are selected from the group consisting of (C 1 -C 4 )alkyl, (C 3 -C 4 )cycloalkyl, (C 3 -C 4 )cycloalkyl(C 1 -C 2 )alkyl, (C 1 -C 4 )alkoxycarbonyl and (C 1 -C 4 )alkylcarbonyl; and suitable substituents for a substitutable ring carbon atom in the Cy 2 is selected from the group consisting fluorine, chlorine, cyano, protected hydroxy, protected amino, (C 1 -C 4 )alkyl, (C 3 -C 4 )cycloalkyl, (C 3 -C 4 )cycloalkyl(C 1 -C 2 )alkyl, (C 1 -C 4 )alkoxy, protected CONH 2 , protected (C 1 -C 4 )alkylaminocarbonyl, di(C 1 -C 4 )alkylaminocarbonyl, protected (C 3 -C 4 )cycloalkylaminocarbonyl, {(C 1 -C 4 )alkyl}{(C 3 -C 4 )cycloalkyl}aminocarbonyl and protected (C 1 -C 4 )alkylcarbonylamino.
In a twenty-first preferred embodiment, with regard to the preparation of an oxazinone compound, A 1 , A 2 , Cy 1 , Cy 2 , R 1 , R 2 , X and E are as defined in any one of the above preferred embodiments and R 3 is 2-methyl-3-propenyl.
In a twenty-second preferred embodiment, with regard to the preparation of an oxazinone compound, A 1 , A 2 , Cy 1 , Cy 2 , R 1 , R 2 , X and E are as defined in any one of the above preferred embodiments and R 3 is 3-propenyl.
In a twenty-third preferred embodiment, A 1 , A 2 , Cy 1 , R 1 , R 2 , X and E are as defined in any one of the above preferred embodiments and Cy 2 is represented by one of the following structural formulas:
G 2a is (C 1 -C 4 )alkyl, (C 3 -C 4 )cycloalkyl or (C 1 -C 4 )haloalkyl; G 2b is hydrogen, fluorine, chlorine, cyano, hydroxy, amino, (C 1 -C 4 )alkyl, (C 3 -C 4 )cycloalkyl, (C 3 -C 4 )cycloalkyl(C 1 -C 2 )alkyl, halo(C 1 -C 4 )alkyl, (C 1 -C 4 )alkoxy, (C 1 -C 4 )haloalkoxy, CONH 2 , (C 1 -C 4 )alkylaminocarbonyl, di(C 1 -C 4 )alkylaminocarbonyl or (C 1 -C 4 )alkylcarbonylamino.
Other embodiments of the present invention are the epoxide compounds and salts thereof, and 2-methyl-3-propenyl intermediates and salts thereof as prepared with the methods of the present invention, in particular, the epoxide compounds and 2-methyl-3-propenyl intermediates corresponding to the above described preferred embodiments.
The following individual compounds can be prepared by a suitable choice of starting materials:
(S)-3-((S)-1-(4-(1,5-dimethyl-6-oxo-1,6-dihydropyridazin-3-yl)phenyl)ethyl)-6-(2-hydroxy-2-methylpropyl)-6-phenyl-1,3-oxazinan-2-one (S)-3-((S)-1-(4-(1,4-dimethyl-6-oxo-1,6-dihydropyridazin-3-yl)phenyl)ethyl)-6-(2-hydroxy-2-methylpropyl)-6-phenyl-1,3-oxazinan-2-one (S)-3-((S)-1-(4-(1,2-dimethyl-1H-benzo[d]imidazol-6-yl)phenyl)ethyl)-6-(2-hydroxy-2-methylpropyl)-6-phenyl-1,3-oxazinan-2-one (S)-6-(2-hydroxy-2-methylpropyl)-3-((S)-1-(4-(1-methyl-1H-benzo[d]imidazol-5-yl)phenyl)ethyl)-6-phenyl-1,3-oxazinan-2-one (S)-3-((S)-1-(4-(1,2-dimethyl-1H-benzo[d]imidazol-5-yl)phenyl)ethyl)-6-(2-hydroxy-2-methylpropyl)-6-phenyl-1,3-oxazinan-2-one (S)-3-((S)-1-(4-(1-(cyclopropylmethyl)-6-oxo-1,6-dihydropyridazin-3-yl)phenyl)ethyl)-6-(2-hydroxy-2-methylpropyl)-6-phenyl-1,3-oxazinan-2-one (S)-3-((S)-1-(4-(1-cyclopropyl-6-oxo-1,6-dihydropyridazin-3-yl)phenyl)ethyl)-6-(2-hydroxy-2-methylpropyl)-6-phenyl-1,3-oxazinan-2-one (S)-3-((S)-1-(4-(1-cyclopropyl-2-oxo-1,2-dihydropyridin-4-yl)phenyl)ethyl)-6-(2-hydroxy-2-methylpropyl)-6-phenyl-1,3-oxazinan-2-one 2-(4-((S)-1-((S)-6-(2-hydroxy-2-methylpropyl)-2-oxo-6-phenyl-1,3-oxazinan-3-yl)ethyl)phenyl)nicotinonitrile (S)-3-((S)-1-(4-(1-(cyclopropylmethyl)-6-oxo-1,6-dihydropyridin-3-yl)phenyl)ethyl)-6-(2-hydroxy-2-methylpropyl)-6-phenyl-1,3-oxazinan-2-one N-ethyl-5-(4-((S)-1-((S)-6-(2-hydroxy-2-methylpropyl)-2-oxo-6-phenyl-1,3-oxazinan-3-yl)ethyl)phenyl)picolinamide 5-(4-((S)-1-((S)-6-(2-hydroxy-2-methylpropyl)-2-oxo-6-phenyl-1,3-oxazinan-3-yl)ethyl)phenyl)-N-methylpicolinamide 5-(4-((S)-1-((S)-6-(2-hydroxy-2-methylpropyl)-2-oxo-6-phenyl-1,3-oxazinan-3-yl)ethyl)phenyl)-N,N-dimethylpicolinamide (S)-3-((S)-1-(4-(1H-benzo[d][1,2,3]triazol-6-yl)phenyl)ethyl)-6-(2-hydroxy-2-methylpropyl)-6-phenyl-1,3-oxazinan-2-one (S)-6-(2-hydroxy-2-methylpropyl)-3-((S)-1-(4-(2-methyl-1H-benzo[d]imidazol-6-yl)phenyl)ethyl)-6-phenyl-1,3-oxazinan-2-one (S)-6-(2-hydroxy-2-methylpropyl)-6-phenyl-3-((S)-1-(4-(1,5,6-trimethyl-2-oxo-1,2-dihydropyridin-4-yl)phenyl)ethyl)-1,3-oxazinan-2-one 2-(4-((S)-1-((S)-6-(2-hydroxy-2-methylpropyl)-2-oxo-6-phenyl-1,3-oxazinan-3-yl)ethyl)phenyl)nicotinonitrile 2-(4-((S)-1-((S)-6-(2-hydroxy-2-methylpropyl)-2-oxo-6-phenyl-1,3-oxazinan-3-yl)ethyl)phenyl)isonicotinonitrile N-tert-butyl-6-(4-((S)-1-((S)-6-(2-hydroxy-2-methylpropyl)-2-oxo-6-phenyl-1,3-oxazinan-3-yl)ethyl)phenyl)nicotinamide (S)-3-((S)-1-(4-(2-ethoxy-6-methylpyridin-4-yl)phenyl)ethyl)-6-(2-hydroxy-2-methylpropyl)-6-phenyl-1,3-oxazinan-2-one (S)-3-((S)-1-(4-(1-ethyl-6-methyl-2-oxo-1,2-dihydropyridin-4-yl)phenyl)ethyl)-6-(2-hydroxy-2-methylpropyl)-6-phenyl-1,3-oxazinan-2-one (S)-3-((S)-1-(4-(6-ethoxy-5-methylpyridin-3-yl)phenyl)ethyl)-6-(2-hydroxy-2-methylpropyl)-6-phenyl-1,3-oxazinan-2-one (S)-3-((S)-1-(4-(1-ethyl-5-methyl-6-oxo-1,6-dihydropyridin-3-yl)phenyl)ethyl)-6-(2-hydroxy-2-methylpropyl)-6-phenyl-1,3-oxazinan-2-one N-cyclopropyl-6-(4-((S)-1-((S)-6-(2-hydroxy-2-methylpropyl)-2-oxo-6-phenyl-1,3-oxazinan-3-yl)ethyl)phenyl)nicotinamide (S)-6-(2-hydroxy-2-methylpropyl)-3-((S)-1-(4-(1-isopropyl-6-oxo-1,6-dihydropyridazin-3-yl)phenyl)ethyl)-6-phenyl-1,3-oxazinan-2-one (S)-6-(2-hydroxy-2-methylpropyl)-3-((S)-1-(4-(6-oxo-1-(2,2,2-trifluoroethyl)-1,6-dihydropyridazin-3-yl)phenyl)ethyl)-6-phenyl-1,3-oxazinan-2-one (S)-3-((S)-1-(4-(1-ethyl-6-oxo-1,6-dihydropyridazin-3-yl)phenyl)ethyl)-6-(2-hydroxy-2-methylpropyl)-6-phenyl-1,3-oxazinan-2-one (S)-6-(2-hydroxy-2-methylpropyl)-3-((S)-1-(4-(1-isopropyl-2-oxo-1,2-dihydropyridin-4-yl)phenyl)ethyl)-6-phenyl-1,3-oxazinan-2-one (S)-6-(2-hydroxy-2-methylpropyl)-3-((S)-1-(4-(6-oxo-1-(2,2,2-trifluoroethyl)-1,6-dihydropyridin-3-yl)phenyl)ethyl)-6-phenyl-1,3-oxazinan-2-one 6-(4-((S)-1-((S)-6-(4-fluorophenyl)-6-(2-hydroxy-2-methylpropyl)-2-oxo-1,3-oxazinan-3-yl)ethyl)phenyl)pyrazine-2-carboxamide 2-(4-((S)-1-((S)-6-(2-hydroxy-2-methylpropyl)-2-oxo-6-phenyl-1,3-oxazinan-3-yl)ethyl)phenyl)-N,N-dimethylthiazole-5-carboxamide (S)-6-(2-hydroxy-2-methylpropyl)-3-((S)-1-(4-(2-oxo-1-(2,2,2-trifluoroethyl)-1,2-dihydropyridin-4-yl)phenyl)ethyl)-6-phenyl-1,3-oxazinan-2-one (S)-3-((S)-1-(4-(1-ethyl-2-oxo-1,2-dihydropyridin-4-yl)phenyl)ethyl)-6-(2-hydroxy-2-methylpropyl)-6-phenyl-1,3-oxazinan-2-one (S)-3-((S)-1-(4-(1,6-dimethyl-2-oxo-1,2-dihydropyridin-4-yl)phenyl)ethyl)-6-(2-hydroxy-2-methylpropyl)-6-phenyl-1,3-oxazinan-2-one 6-(4-((S)-1-((S)-6-(4-fluorophenyl)-6-(2-hydroxy-2-methylpropyl)-2-oxo-1,3-oxazinan-3-yl)ethyl)phenyl)pyrazine-2-carbonitrile (S)-3-((S)-1-(4-(1-ethyl-6-oxo-1,6-dihydropyridin-3-yl)phenyl)ethyl)-6-(4-fluorophenyl)-6-(2-hydroxy-2-methylpropyl)-1,3-oxazinan-2-one (S)-3-((S)-1-(4-(1,5-dimethyl-6-oxo-1,6-dihydropyridin-3-yl)phenyl)ethyl)-6-(2-hydroxy-2-methylpropyl)-6-phenyl-1,3-oxazinan-2-one (S)-6-(4-fluorophenyl)-6-(2-hydroxy-2-methylpropyl)-3-((S)-1-(4-(1-methyl-6-oxo-1,6-dihydropyridazin-3-yl)phenyl)ethyl)-1,3-oxazinan-2-one 6-(4-((S)-1-((S)-6-(2-hydroxy-2-methylpropyl)-2-oxo-6-phenyl-1,3-oxazinan-3-yl)ethyl)phenyl)-N,N-dimethylnicotinamide (S)-6-(4-fluorophenyl)-6-(2-hydroxy-2-methylpropyl)-3-((S)-1-(4-(6-methylpyridazin-3-yl)phenyl)ethyl)-1,3-oxazinan-2-one 4-(4-((S)-1-((S)-6-(2-hydroxy-2-methylpropyl)-2-oxo-6-phenyl-1,3-oxazinan-3-yl)propyl)phenyl)-2,6-dimethylpyridine 1-oxide 5-(4-((S)-1-((S)-6-(4-fluorophenyl)-6-(2-hydroxy-2-methylpropyl)-2-oxo-1,3-oxazinan-3-yl)ethyl)phenyl)pyrazine-2-carbonitrile 5-fluoro-2-(4-((S)-1-((S)-6-(2-hydroxy-2-methylpropyl)-2-oxo-6-phenyl-1,3-oxazinan-3-yl)ethyl)phenyl)pyridine 1-oxide (S)-6-(2-hydroxy-2-methylpropyl)-3-((S)-1-(4-(5-methylpyrazin-2-yl)phenyl)ethyl)-6-phenyl-1,3-oxazinan-2-one (S)-6-(2-hydroxy-2-methylpropyl)-3-((S)-1-(4-(1-isopropyl-6-oxo-1,6-dihydropyridin-3-yl)phenyl)ethyl)-6-phenyl-1,3-oxazinan-2-one 6-(4-((S)-1-((S)-6-(2-hydroxy-2-methylpropyl)-2-oxo-6-phenyl-1,3-oxazinan-3-yl)ethyl)phenyl)-N-methylnicotinamide (S)-6-(2-hydroxy-2-methylpropyl)-3-((S)-1-(4-(2-methylpyrimidin-5-yl)phenyl)ethyl)-6-phenyl-1,3-oxazinan-2-one (S)-6-(2-hydroxy-2-methylpropyl)-3-((S)-1-(4-(1-methyl-2-oxo-1,2-dihydropyridin-4-yl)phenyl)propyl)-6-phenyl-1,3-oxazinan-2-one (S)-6-(2-hydroxy-2-methylpropyl)-3-((S)-1-(4-(1-methyl-6-oxo-1,6-dihydropyridazin-3-yl)phenyl)ethyl)-6-phenyl-1,3-oxazinan-2-one (S)-6-(2-hydroxy-2-methylpropyl)-3-((S)-1-(4-(1-methyl-6-oxo-1,6-dihydropyridin-3-yl)phenyl)propyl)-6-phenyl-1,3-oxazinan-2-one (S)-3-((S)-1-(4-(1-ethyl-6-oxo-1,6-dihydropyridin-3-yl)phenyl)ethyl)-6-(2-hydroxy-2-methylpropyl)-6-phenyl-1,3-oxazinan-2-one (S)-3-((S)-1-(4-(1-ethyl-6-oxo-1,6-dihydropyridin-3-yl)phenyl)propyl)-6-(2-hydroxy-2-methylpropyl)-6-phenyl-1,3-oxazinan-2-one 6-(4-((S)-1-((S)-6-(2-hydroxy-2-methylpropyl)-2-oxo-6-phenyl-1,3-oxazinan-3-yl)ethyl)phenyl)nicotinamide (S)-3-((S)-1-(4-(5-fluoropyridin-2-yl)phenyl)ethyl)-6-(2-hydroxy-2-methylpropyl)-6-phenyl-1,3-oxazinan-2-one (S)-6-(2-hydroxy-2-methylpropyl)-3-((S)-1-(4-(2-methylpyrimidin-4-yl)phenyl)ethyl)-6-phenyl-1,3-oxazinan-2-one (S)-6-(2-hydroxy-2-methylpropyl)-6-phenyl-3-((S)-1-(4-(pyrimidin-4-yl)phenyl)ethyl)-1,3-oxazinan-2-one (S)-6-(2-hydroxy-2-methylpropyl)-3-((S)-1-(4-(6-methylpyridazin-3-yl)phenyl)ethyl)-6-phenyl-1,3-oxazinan-2-one (S)-6-(2-hydroxy-2-methylpropyl)-6-phenyl-3-((S)-1-(4-(pyrazin-2-yl)phenyl)ethyl)-1,3-oxazinan-2-one (S)-6-(2-hydroxy-2-methylpropyl)-3-((S)-1-(4-(1-methyl-2-oxo-1,2-dihydropyridin-4-yl)phenyl)ethyl)-6-phenyl-1,3-oxazinan-2-one 6-(4-((S)-1-((S)-6-(2-hydroxy-2-methylpropyl)-2-oxo-6-phenyl-1,3-oxazinan-3-yl)ethyl)phenyl)nicotinonitrile (S)-3-((S)-1-(4-(2,6-dimethylpyridin-4-yl)phenyl)ethyl)-6-(2-hydroxy-2-methylpropyl)-6-phenyl-1,3-oxazinan-2-one (S)-3-((S)-1-(4-(2,6-dimethylpyridin-4-yl)phenyl)ethyl)-6-(4-fluorophenyl)-6-(2-hydroxy-2-methylpropyl)-1,3-oxazinan-2-one 4-(4-((S)-1-((S)-6-(2-hydroxy-2-methylpropyl)-2-oxo-6-phenyl-1,3-oxazinan-3-yl)ethyl)phenyl)-2,6-dimethylpyridine 1-oxide 6-(4-((S)-1-((S)-6-(4-fluorophenyl)-6-(2-hydroxy-2-methylpropyl)-2-oxo-1,3-oxazinan-3-yl)ethyl)phenyl)nicotinonitrile 4-(4-((S)-1-((S)-6-(4-fluorophenyl)-6-(2-hydroxy-2-methylpropyl)-2-oxo-1,3-oxazinan-3-yl)ethyl)phenyl)-2,6-dimethylpyridine 1-oxide 4-(4-((S)-1-((S)-6-(4-fluorophenyl)-6-(2-hydroxy-2-methylpropyl)-2-oxo-1,3-oxazinan-3-yl)ethyl)phenyl)-2-methylpyridine 1-oxide (S)-6-(2-hydroxy-2-methylpropyl)-3-((S)-1-(4-(1-methyl-6-oxo-1,6-dihydropyridin-3-yl)phenyl)ethyl)-6-phenyl-1,3-oxazinan-2-one (S)-6-(4-fluorophenyl)-6-(2-hydroxy-2-methylpropyl)-3-((S)-1-(4-(pyridin-2-yl)phenyl)ethyl)-1,3-oxazinan-2-one (S)-6-(4-fluorophenyl)-6-(2-hydroxy-2-methylpropyl)-3-((S)-1-(4-(6-methoxypyridin-3-yl)phenyl)ethyl)-1,3-oxazinan-2-one (S)-6-(2-hydroxy-2-methylpropyl)-6-phenyl-3-((S)-1-(4-(pyridin-2-yl)phenyl)ethyl)-1,3-oxazinan-2-one (S)-6-(2-hydroxy-2-methylpropyl)-3-((S)-1-(4-(6-methoxypyridin-3-yl)phenyl)ethyl)-6-phenyl-1,3-oxazinan-2-one (S)-6-(2-hydroxy-2-methylpropyl)-3-((S)-1-(4-(2-methylpyridin-4-yl)phenyl)ethyl)-6-phenyl-1,3-oxazinan-2-one (S)-6-(4-fluorophenyl)-6-(2-hydroxy-2-methylpropyl)-3-((S)-1-(4-(2-methylpyridin-4-yl)phenyl)ethyl)-1,3-oxazinan-2-one (S)-6-(4-fluorophenyl)-6-(2-hydroxy-2-methylpropyl)-3-((S)-1-(4-(1-methyl-6-oxo-1,6-dihydropyridin-3-yl)phenyl)ethyl)-1,3-oxazinan-2-one (S)-3-((S)-1-(4′-fluorobiphenyl-4-yl)ethyl)-6-(2-hydroxy-2-methylpropyl)-6-phenyl-1,3-oxazinan-2-one (S)-3-((S)-1-(2′,4′-difluorobiphenyl-4-yl)ethyl)-6-(4-fluorophenyl)-6-(2-hydroxy-2-methylpropyl)-1,3-oxazinan-2-one
As used herein, “β-haloalcohol compound,” refers to compound represented by structural formula (II)
wherein X includes any suitable leaving group as described herein, not just halogen.
Suitable leaving groups include, but are not limited to halides, alkylsulfonates, trifluoromethanesulfonate (triflate) and phenylsulfonates which are optionally substituted with a methyl, halogen, nitro and the like, for example, methanesulfonate (mesylate), p-toluenesulfonate (tosylate), p-bromobenzenesulfonate (brosylate), p-nitrobenzenesulfonate (nosylate) and the like. Typically, leaving groups are Cl, Br, I or —OSO 2 R, wherein R is (C 1 -C 4 )alkyl optionally substituted with one or more F, or phenyl optionally substituted with halogen, (C 1 -C 4 )alkyl or NO 2 . Most typically, leaving groups are Cl, Br, I or —OSO 2 R.
The term “biaryl group” as used herein refers to a group where an optionally substituted aryl or optionally substituted heteroaryl is bonded to another optionally substituted aryl or optionally substituted heteroaryl (e.g., biphenyl).
The term “alkyl” as used herein refers to a straight chain or branched saturated hydrocarbyl group having 1-10 carbon atoms and includes, for example, methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl, n-decyl and the like.
The term “cycloalkyl” means a monocyclic, bicyclic or tricyclic, saturated hydrocarbon ring having 3-10 carbon atoms and includes, for example, cyclopropyl (c-Pr), cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, bicyclo[2.2.2]octyl, bicyclo[2.2.1]heptyl, spiro[4.4]nonane, adamantyl and the like.
The term “aryl” means an aromatic radical which is a phenyl group, a naphthyl group, an indanyl group or a tetrahydronaphthalene group. An aryl group is optionally substituted with 1-4 substituents. Exemplary substituents include alkyl, alkoxy, alkylthio, alkylsulfonyl, halogen, trifluoromethyl, dialkylamino, nitro, cyano, CO 2 H, CONH 2 , N-monoalkyl-substituted amido and N,N-dialkyl-substituted amido.
The term “heteroaryl” means a 5- and 6-membered heteroaromatic radical which may optionally be fused to a saturated or unsaturated ring containing 0-4 heteroatoms selected from N, O, and S and includes, for example, a heteroaromatic radical which is 2- or 3-thienyl, 2- or 3-furanyl, 2- or 3-pyrrolyl, 2-, 3-, or 4-pyridyl, 2-pyrazinyl, 2-, 4-, or 5-pyrimidinyl, 3- or 4-pyridazinyl, 1H-indol-6-yl, 1H-indol-5-yl, 1H-benzimidazol-6-yl, 1H-benzimidazol-5-yl, 2-, 4-, 5-, 6-, 7- or 8-quinazolinyl, 2-, 3-, 5-, 6-, 7- or 8-quinoxalinyl, 2-, 3-, 4-, 5-, 6-, 7- or 8-quinolinyl, 1-, 3-, 4-, 5-, 6-, 7- or 8-isoquinolinyl, 2-, 4-, or 5-thiazolyl, 2-, 3-, 4-, or 5-pyrazolyl, 2-, 3-, 4-, or 5-imidazolyl. A heteroaryl is optionally substituted. Exemplary substituents include alkyl, alkoxy, alkylthio, alkylsulfonyl, halogen, trifluoromethyl, dialkylamino, nitro, cyano, CO 2 H, CONH 2 , N-monoalkyl-substituted amido and N,N-dialkyl-substituted amido, or by oxo to form an N-oxide.
The term “heterocyclyl” means a 4-, 5-, 6- and 7-membered saturated or partially unsaturated heterocyclic ring containing 1 to 4 heteroatoms independently selected from N, O, and S. Exemplary heterocyclyls include pyrrolidine, pyrrolidin-2-one, 1-methylpyrrolidin-2-one, piperidine, piperidin-2-one, dihydropyridine, tetrahydropyridine, piperazine, 1-(2,2,2-trifluoroethyl)piperazine, 1,2-dihydro-2-oxopyridine, 1,4-dihydro-4-oxopyridine, piperazin-2-one, 3,4,5,6-tetrahydro-4-oxopyrimidine, 3,4-dihydro-4-oxopyrimidine, tetrahydrofuran, tetrahydropyran, tetrahydrothiophene, tetrahydrothiopyran, isoxazolidine, 1,3-dioxolane, 1,3-dithiolane, 1,3-dioxane, 1,4-dioxane, 1,3-dithiane, 1,4-dithiane, oxazolidin-2-one, imidazolidin-2-one, imidazolidine-2,4-dione, tetrahydropyrimidin-2(1H)-one, morpholine, N-methylmorpholine, morpholin-3-one, 1,3-oxazinan-2-one, thiomorpholine, thiomorpholine 1,1-dioxide, tetrahydro-1,2,5-thiaoxazole 1,1-dioxide, tetrahydro-2H-1,2-thiazine 1,1-dioxide, hexahydro-1,2,6-thiadiazine 1,1-dioxide, tetrahydro-1,2,5-thiadiazole 1,1-dioxide isothiazolidine 1,1-dioxide, 6-oxo-1,6-dihydropyridazin-3-yl, 6-oxo-1,6-dihydropyridazin-4-yl, 5-oxo-4,5-dihydro-1H-1,2,4-triazol-3-yl and 5-oxo-4,5-dihydro-1H-imidazol-2-yl. A heterocyclyl can be optionally substituted with 1-4 substituents. Exemplary substituents include alkyl, haloalkyl, halogen and oxo.
The term “alkoxy group” (also herein referred to as “alkoxy”) as used herein, refers to an alkyl-O— group or a cycloalkyl-O— group, where the preferred alkyl and cycloalkyl groups and optional substituents thereon are those given above. An alkoxy group can be unsubstituted or substituted with one or more substituents.
The term “alkenyl group” (also herein referred to as “alkenyl”) as used herein, refers to a straight chain or branched hydrocarbyl group which includes one or more double bonds. Typically, an alkenyl group includes between 2 and 12 carbon atoms (i.e., (C 2 -C 12 )-alkenyl). Suitable alkenyl groups include but are not limited to n-butenyl, cyclooctenyl and the like. An alkenyl group can be unsubstituted or substituted with one or more substituents.
The term “alkynyl” group (also herein referred to as “alkynyl”) as used herein, refers to a straight chain or branched hydrocarbyl group which includes one or more triple bonds. The triple bond of an alkynyl group can be unconjugated or conjugated to another unsaturated group. Suitable alkynyl groups include, but are not limited to, (C 2 -C 8 )-alkynyl groups, such as ethynyl, propynyl, butynyl, pentynyl, hexynyl, methylpropynyl, 4-methyl-1-butynyl, 4-propyl-2-pentynyl-, and 4-butyl-2-hexynyl. An alkynyl group can be unsubstituted or substituted with one or more substituents.
The term “alkylene group” (also herein referred to as “alkylene) as used herein, refers to a group represented by —[CH 2 ]—, wherein z is a positive integer, preferably from one to eight, more preferably from one to four.
The terms “cycloalkyl alkyl”, “alkoxy alkyl” and the like, that is, terms that consist of a combination of terms as defined above refer to groups that contain the groups referred to by the terms. For example, a (C a -C b )alkoxy(C c -C d )alkyl is a group that includes an alkoxy group with between a and b carbon atoms that is covalently bonded to an alkyl group with between c and d carbon atoms.
The above groups can be unsubstituted or optionally substituted. Suitable substituents are those which do not substantially interfere with the reactions described herein, that is, that do not substantially decrease the yield (e.g., a decrease of greater than 50%) or cause a substantial amount of by-product formation (e.g., where by-products represent at least 50% of the theoretical yield). However, “interfering” substituents can be used, provided that they are first converted to a protected form. Suitable protecting groups are known in the art and are disclosed, for example, in Greene and Wuts, “Protective Groups in Organic Synthesis”, John Wiley & Sons (2007).
Suitable substituents for above groups include, for example, unless otherwise indicated, (C 1 -C 4 )alkyl, (C 1 -C 4 )alkoxy, (C 1 -C 4 )alkoxycarbonyl, benzyloxycarbonyl, hydroxy(C 1 -C 4 )alkyl, cyano(C 1 -C 4 )alkyl, (C 1 -C 4 )alkylamino, di(C 1 -C 4 )alkylamino, halogen, cyano, oxo, nitro, hydroxy, amino, MeSO 2 —, MeSO 2 N(Me)(C 1 -C 4 )alkyl, MeSO 2 NH(C 1 -C 4 )alkyl, H 2 NC(═O)CMe 2 (C 1 -C 4 )alkyl, H 2 NC(═O)CHMe(C 1 -C 4 )alkyl, H 2 NC(═O)CH 2 (C 1 -C 4 )alkyl, —OR, —NR 2 , —COOR, —CONR 2 , —SO k R (k is 0, 1 or 2), wherein each R is independently —H, an alkyl group, a cycloalkyl group or an aryl group.
When a disclosed compound or its pharmaceutically acceptable salt is named or depicted by structure, it is to be understood that solvates or hydrates of the compound or its physiologically acceptable salts are also included. “Solvates” refer to crystalline forms wherein solvent molecules are incorporated into the crystal lattice during crystallization. Solvate may include water or nonaqueous solvents such as ethanol, isopropanol, DMSO, acetic acid, ethanolamine, and EtOAc. Solvates, wherein water is the solvent molecule incorporated into the crystal lattice, are typically referred to as “hydrates.” Hydrates include stoichiometric hydrates as well as compositions containing variable amounts of water.
Certain of the disclosed compounds may exist in various stereoisomeric forms. Stereoisomers are compounds that differ only in their spatial arrangement. Enantiomers are pairs of stereoisomers whose mirror images are not superimposable, most commonly because they contain an asymmetrically substituted carbon atom that acts as a chiral center. “Enantiomer” means one of a pair of molecules that are mirror images of each other and are not superimposable. Diastereomers are stereoisomers that are not related as mirror images, most commonly because they contain two or more asymmetrically substituted carbon atoms. The symbol “*” in a structural formula represents the presence of a chiral carbon center. “R” and “S” represent the configuration of substituents around one or more chiral carbon atoms. Thus, “R*” and “S*” denote the relative configurations of substituents around one or more chiral carbon atoms.
The compounds of the invention may be prepared as individual isomers by either isomer-specific synthesis or resolved from an isomeric mixture. Conventional resolution techniques include forming the salt of a free base of each isomer of an isomeric pair using an optically active acid (followed by fractional crystallization and regeneration of the free base), forming the salt of the acid form of each isomer of an isomeric pair using an optically active amine (followed by fractional crystallization and regeneration of the free acid), forming an ester or amide of each of the isomers of an isomeric pair using an optically pure acid, amine or alcohol (followed by chromatographic separation and removal of the chiral auxiliary), or resolving an isomeric mixture of either a starting material or a final product using various well known chromatographic methods.
When the stereochemistry of a disclosed compound is named or depicted by structure, the named or depicted stereoisomer is at least 60%, 70%, 80%, 90%, 99% or 99.9% by weight pure relative to the other stereoisomers. When a single enantiomer is named or depicted by structure, the depicted or named enantiomer is at least 60%, 70%, 80%, 90%, 99% or 99.9% by weight optically pure. Percent optical purity by weight is the ratio of the weight of the enantiomer over the weight of the enantiomer plus the weight of its optical isomer.
When a disclosed compound is named or depicted by structure without indicating the stereochemistry, and the compound has at least one chiral center, it is to be understood that the name or structure encompasses one enantiomer of compound free from the corresponding optical isomer, a racemic mixture of the compound and mixtures enriched in one enantiomer relative to its corresponding optical isomer.
When a disclosed compound is named or depicted by structure without indicating the stereochemistry and has at least two chiral centers, it is to be understood that the name or structure encompasses a diastereomer free of other diastereomers, a pair of diastereomers free from other diastereomeric pairs, mixtures of diastereomers, mixtures of diastereomeric pairs, mixtures of diastereomers in which one diastereomer is enriched relative to the other diastereomer(s) and mixtures of diastereomeric pairs in which one diastereomeric pair is enriched relative to the other diastereomeric pair(s).
The compounds of the invention may be present in the form of pharmaceutically acceptable salts. For use in medicines, the salts of the compounds of the invention refer to non-toxic “pharmaceutically acceptable salts.” Pharmaceutically acceptable salt forms include pharmaceutically acceptable acidic/anionic or basic/cationic salts.
Pharmaceutically acceptable basic/cationic salts include, the sodium, potassium, calcium, magnesium, diethanolamine, n-methyl-D-glucamine, L-lysine, L-arginine, ammonium, ethanolamine, piperazine and triethanolamine salts.
Pharmaceutically acceptable acidic/anionic salts include, the acetate, benzenesulfonate, benzoate, bicarbonate, bitartrate, bromide, calcium edetate, camsylate, carbonate, chloride, citrate, dihydrochloride, edetate, edisylate, estolate, esylate, fumarate, glyceptate, gluconate, glutamate, glycollylarsanilate, hexylresorcinate, hydrobromide, hydrochloride, hydroxynaphthoate, iodide, isethionate, lactate, lactobionate, malate, maleate, malonate, mandelate, mesylate, methylsulfate, mucate, napsylate, nitrate, pamoate, pantothenate, phosphate/diphospate, polygalacturonate, salicylate, stearate, subacetate, succinate, sulfate, hydrogensulfate, tannate, tartrate, teoclate, tosylate, and triethiodide salts.
Protecting groups for an hydroxyl group —OH and reactions and conditions for protecting and deprotecting the hydroxyl group are well known in the art and are disclosed, for example, in Greene and Wuts, “Protective Groups in Organic Synthesis”, John Wiley & Sons (2007), Chapter 2 and references cited therein. For example, a protecting group may protect a hydroxyl group as ether. Such protecting groups include, but are not limited to methyl, methoxymethyl, methylthiomethyl, (phenyldimethylsilyl)methoxymethyl, benzyloxymethyl, p-methoxybenzyloxymethyl, [3,4-dimethoxybenzyl)oxy]methyl, p-nitrobenzyloxymethyl, o-nitrobenzyloxymethyl, [(R)-1-(2-nitrophenyl)ethoxy]methyl, (4-methoxyphenoxy)methyl, guaiacolmethyl, [(p-phenylphenyl)oxy]methyl, t-butoxymethyl, 4-pentenyloxymethyl, siloxymethyl, 2-methoxyethoxymethyl, 2-cyanoethoxymethyl, bis(2-chloroethoxy)methyl, 2,2,2-trichloroethoxymethyl, 2-(trimethylsilyl)ethoxymethyl, menthoxymethyl, O-bis(2-acetoxyethoxy)methyl, tetrahydropyranyl, fluorous tetrahydropyranyl, 3-bromotetrahydropyranyl, tetrahydrothiopyranyl, 1-methoxycyclohexyl, 4-methoxytetrahydropyranyl, 4-methoxytetrahydrothiopyranyl, 4-methoxytetrahydrothiopyranyl, S,S-dioxide, 1-[(2-chloro-4-methyl)phenyl]-4-methoxypiperidin-4-yl, 1-(2-fluorophenyl)-4-methoxypiperidin-4-yl, 1-(4-chlorophenyl)-4-methoxypiperidin-4-yl, 1,4-dioxan-2-yl, tetrahydrofuranyl, tetrahydrothiofuranyl, 2,3,3a,4,5,6,7,7a-octahyrdo-7,8,8-trimethyl-4,7-methanobenzofuran-2-yl, 1-ethoxyethyl, 1-(2-chloroethoxy)ethyl, 2-hydroxyethyl, 2-bromoethyl, 1-[2-(trimethylsilyl)ethoxy]ethyl, 1-methyl-1-methoxyethyl, 1-methyl-1-benzyloxyethyl, 1-methyl-1-benzyloxy-2-fluoroethyl, 1-methyl-1-phenoxyethyl, 2,2,2-trichloroethyl, 1,1,-dianisyl-2,2,2,-trichloroethyl, 1,1,1,3,3,3-hexafluoro-2-phenylisopropyl, 1-(2-cyanoethoxy)ethyl, 2-trimethylsilylethyl, 2-(benzylthio)ethyl, 2-(phenylselenyl)ethyl, t-butyl, cyclohexyl, 1-methyl-1′-cyclopropylmethyl, allyl, prenyl, cinnamyl, 2-phenallyl, propargyl, p-chlorophenyl, p-methoxyphenyl, p-nitrophenyl, 2,4-dinitrophenyl, 2,3,5,6-tetrafluoro-4-(trifluoromethyl)phenyl, benzyl, p-methoxybenzyl, 3,4-dimethoxybenzyl, 2,6-dimethoxybenzyl, o-nitrobenzyl, p-nitrobenzyl, pentadienylnitrobenzyl, pentadienylnitropiperonyl, halobenzyl, 2,6-dichlorobenzyl, 2,4-dichlorobenzyl, 2,6-difluorobenzyl, p-cyanobenzyl, fluoros benzyl, 4-fluorousalkoxybenzyl, trimethylsilylxylyl, p-phenylbenzyl, 2-phenyl-2-propyl(cumyl), p-acylaminobenzyl, p-azidobenzyl, 4-azido-3-chlorobenzyl, 2- and 4-trifluoromethylbenzyl, p-(methylsulfinyl)benzyl, p-siletanylbenzyl, 4-acetoxybenzyl, 4-(2-trimethylsilyl)ethoxymethoxybenzyl, 2-naphthylmethyl, 2- and 4-picolyl, 3-methyl-2-picolyl N-oxido, 2-quinolinylmethyl, 6-methoxy-2-(4-methylpheny)-4-quinolinemethyl, 1-pyrenylmethyl, diphenylmethyl, 4-methoxydiphenylmethyl, 4-phenyldiphenylmethyl, p,p′-dinitrobenzhydryl, 5-dibenzosuberyl, triphenylmethyl, tris(4-t-butylphenyl)methyl, α-naphthyldiphenylmethyl, p-methoxyphenyldiphenylmethyl, di(p-methoxyphenyl)phenylmethyl, tri(p-methoxyphenyl)methyl, 4-(4′-bromophenacyloxy)phenyldiphenylmethyl, 4,4′,4″-tris(4,5-dichlorophthalimidophenyl)methyl, 4,4′,4″-tris(levulinoyloxyphenyl)methyl, 4,4′,4″tris(benzoyloxyphenyl)methyl, 4,4′-dimethoxy-3″-[N-(imidazolylmethyl)trityl, 4,4′-dimethoxy-3″-[N-(imidazolylethyl)carbamoyl]trityl, bis(4-methoxyphenyl)-1′-pyrenylmethyl, 4-(17-tetrabenzo[a,c,g,i]fluorenylmethyl)-4,4″-dimethoxytrityl, 9-anthryl, 9-(9-phenyl)xanthenyl, 9-phenylthioxanthyl, 9-(9-phenyl-10-oxo)anthryl, 1,3-benzodithiolan-2-yl, 4,5-bis(ethoxycarbonyl-[1,3]-dioxolan-2-yl, benzisothiazolyl S,S-dioxido, trimethylsilyl, triethylsilyl, triisopropylsilyl, dimethylisopropylsiyl, diethylisopropylsilyl, dimethylthexylsilyl, 2-norbornyldimethylsily, t-butyldimethylsilyl, t-butyldiphenylsilyl, tribenzylsilyl, tri-p-xylylsilyl, triphenylsilyl, diphenylmethylsilyl, di-t-butylmethylsilyl, bis(t-butyl)-1-pyrenylmethoxysilyl, tris(trimethylsilyl)silyl, sisyl, (2-hydroxystyryl)dimethylsilyl, (2-hydroxystyryl)diisopropylsily, t-butylmethoxyphenylsilyl, t-butoxydiphenylsilyl, 1,1,3,3-tetraisopropyl-3-[2-(triphenylmethoxy)ethoxy]disiloxane-1-yl, fluorous silyl. Alternatively, suitable protecting groups protect the hydroxyl group as esters, for example, formate, benzoylformate, acetate, chloroacetate, dichloroacetate, trichloroacetate, trichloroacetamidate, trifluoroacetate, methoxyacetate, triphenylmethoxyacetate, phenoxyacetate, p-chlorophenoxyacetate, phenylacetate, p-P-phenylacetate, diphenylacetate, 3-phenylpropionate, bisfluorous chain type propanoyl (Bfp-OR), 4-pentenoate, 4-oxopentanoate (levulinate), 4,4-(ethylenedithio)pentanoate, 5-[3-Bis(4-methoxyphenyl)hydroxymethylphenoxy]levulinate, pivaloate, 1-adamantoate, crotonate, 4-methoxycrotonate, benzoate, p-phenylbenzoate, 2,4,6-trimethylbenzoate (mesitoate), 4-bromobenzoate, 2,5-difluorobenzoate, p-nitrobenzoate, picolinate, nicotinate, 2-(azidomethyl)benzoate, 4-azidobutyrate, (2-azidomethyl)phenylacetate, 2-{[(tritylthio)oxy]methyl}benzoate, 2-{[(4-methoxytritylthio)oxy]methyl}benzoate, 2-{[methyl(tritylthio)amino]methyl}benzoate, 2{{[4-methoxytrityl)thio]methylamino}-methyl}benzoate, 2-(allyloxy)phenylacetate, 2-(prenyloxymethyl)benzoate, 6-(levulinyloxymethyl)-3-methoxy-2- and 4-nitrobenzoate, 4-benzyloxybutyrate, 4-trialkylsiloxybutrate, 4-acetoxy-2,2-dimethylbutyrate, 2,2-dimethyl-4-pentenoate, 2-iodobenzoate, 4-nitro-4-methylpentanoate, o-(dibromomethyl)benzoate, 2-formylbenzenesulfonate, 4-methylthiomethoxy)butyrate, 2-methylthiomethoxymethyl)benzoate, 2-(chloroacetoxymethyl)benzoate, 2[(2-chloroacetoxy)ethyl]benzoate, 2-[2-(benzyloxy)ethyl]benzoate, 2-[2-(4-methoxybenzyloxy)ethyl]benzoate, 2,6-dichloro-4-methylphenoxyacetate, 2,6-dichloro-4-(1,1,3,3-tetramethylbutyl)phenoxyacetate, 2,4-bis(1,1-imethylpropyl)phenoxyacetate, chlorodiphenylacetate, isobutyrate, monosuccinoate, (E)-2-methyl-2-butenoate tigloate), o-(methoxycarbonyl)benzoate, p-P-benzoate, α-naphthoate, nitrate, alkyl N,N,N′,N′-tetramethylphosphorodiamidate, 2-chlorobenzoate, as sulfonates, sulfenates and sulfinates such as sulfate, allylsulfonate, ethanesulfonate (mesylate), benzylsulfonate, tosylate, 2-[(4-nitrophenyl)ethyl]sulfonate, 2-trifluoromethylsulfonate, 4-monomethoxytritylsulfenate, alkyl 2,4-initrophenylsulfenate, 2,2,5,5-tetramethylpyrrolidin-3-one-1-sulfinate, borate, dimethylphosphinothioyl, as carbonates such as alkyl methyl carbonate, methoxymethyl carbonate, 9-fluorenylmethyl carbonate, ethyl carbonate, bromoethyl carbonate, 2-(methylthiomethoxy)ethyl carbonate, 2,2,2-trichloroethyl carbonate, 1,1-dimethyl-2,2,2-trichloroethyl carbonate, 2-(trimethylsilyl)ethyl carbonate, 2-[dimethyl(2-naphthylmethyl)silyl]ethyl carbonate, 2-(phenylsulfonyl)ethyl carbonate, 2-(triphenylphosphonio)ethyl carbonate, cis-[4-[[(-methoxytrityl)sulfenyl]oxy]tetraydrofuran-3-yl]oxy carbonate, isobutyl carbonate, t-butyl carbonate, vinyl carbonate, allyl carbonate, cinnamyl carbonate, propargyl carbonate, p-chlorophenyl carbonate, p-nitrophenyl carbonate, 4-ethoxyl-1-naphthyl carbonate, 6-bromo-7-hydroxycoumarin-4-ylmethyl carbonate, benzyl carbonate, o-nitrobenzyl carbonate, p-nitrobenzyl carbonate, p-methoxybenzyl carbonate, 3,4-dimethoxybenzyl carbonate, anthraquinon-2-ylmethyl carbonate, 2-dansylethyl carbonate, 2-(4-nitrophenyl)ethyl, 2-(2,4-nitrophenyl)ethyl, 2-(2-nitrophenyl)propyl, 2-(3,4-methylenedioxy-6-nitrophenylpropyl, 2-cyano-1-phenylethyl carbonate, 2-(2-pyridyl)amino-1-phenylethyl carbonate, 2-[N-methyl-N-(2-pyridyl]amino-1-phenylethyl carbonate, phenacyl carbonate, 3′,5′-dimethoxybenzoin carbonate, methyl dithiocarbonate, S-benzyl thiocarbonate, and carbamates such as dimethylthiocarbamate, N-phenylcarbamate, and N-methyl-N-(o-nitrophenyl) carbamate.
Protecting groups for a carbonyl group and reactions and conditions for protecting and deprotecting the carbonyl group are well known in the art and are disclosed, for example, in Greene and Wuts, “Protective Groups in Organic Synthesis”, John Wiley & Sons (2007), Chapter 4 and references cited therein. For example, a protecting group may protect a carbonyl group as acetal or ketal. These acetals and ketals include acyclic acetals and ketals (e.g., dimethyl, diisopropyl, bis(2,2,2-trichloroethyl), cyclic acetals and ketals (e.g., 1,3-dioxanes, 1,3-dioxolanes, 1,3-dioxapane and the like), chiral acetals and ketals (e.g., (4R,5R)-diphenyl-1,3-dioxolane, 4,5-dimethyl-1,3-dioxolane, trans-1,2-cyclohexanediol ketal and the like), dithio acetals and ketals (e.g., S,S′-dimethyl, S,S′-diethyl, S,S′-dipropyl, 1,3-dithiane and the like), and monothio acetals and ketals.
Protecting groups for a carboxyl group and reactions and conditions for protecting and deprotecting the carboxyl group are well known in the art and are disclosed, for example, in Greene and Wuts, “Protective Groups in Organic Synthesis”, John Wiley & Sons (2007), Chapter 5 and references cited therein. For example, a protecting group may protect a carboxyl group as ester. These esters include, but are not limited to substituted methyl esters (e.g., 9-fluorenylmethyl, methoxymethyl, methoxyethoxymethyl and the like), 2-substituted ethyl esters (e.g., 2,2,2-trichloroethyl, 2-haloethyl, 2-(trimethylsilyl)ethyl and the like), 2,6-dialkylphenyl esters (e.g., 2,6-dimethylphenyl, 2,6-di-t-butyl-4-methylphenyl, pentafluorophenyl and the like), substituted benzyl esters (e.g., triphenylmethyl, diphenylmethyl, 9-anthrylmethyl and the like), silyl esters (e.g., trimethylsilyl, triethylsilyl, t-butyldimethylsilyl and the like. Alternatively, for example, a protecting group may protect a carboxyl group as amide (e.g., N,N-dimethyl, pyrrolidinyl, piperidinyl and the like) or hydrazide (e.g., N-phenyl).
Protecting groups for an amino group and reactions and conditions for protecting and deprotecting the amino group are well known in the art and are disclosed, for example, in Greene and Wuts, “Protective Groups in Organic Synthesis”, John Wiley & Sons (2007), Chapter 7 and references cited therein. For example, a protecting group may protect an amino group as carbamate (e.g., 9-fluorenylmethyl, 2,2,2-trichloroethyl, 4-phenylacetoxybenzyl, 2-methylthioethyl, m-nitrophenyl, and the like) or amide (e.g., formamide, acetamide, 3-phenylpropanamide).
Protecting groups for an aromatic heterocycle such as, for example, imidazole, pyrrole, and indole, and reactions and conditions for protecting and deprotecting the aromatic heterocycles are well known in the art and are disclosed, for example, in Greene and Wuts, “Protective Groups in Organic Synthesis”, John Wiley & Sons (2007), Chapter 7 and references cited therein. For example, a protecting group may protect an aromatic heterocycle as N-sulfonyl derivative (e.g., N,N-dimethylsulfonamide, methanesulfoneamide, mesitylenesulfonamide and the like), carbamate (e.g., benzyl, 2,2,2-trichloroethyl, 2-(trimethylsilyl)ethyl and the like), N-alkyl and N-aryl derivatives, N-trialkylsilyl, N-allyl, N-benzyl, amino acetal derivative, or amide.
Protecting groups for an amide group, and reactions and conditions for protecting and deprotecting the amide group are well known in the art and are disclosed, for example, in Greene and Wuts, “Protective Groups in Organic Synthesis”, John Wiley & Sons (2007), Chapter 7 and references cited therein. For example, a protecting group may protect an amide group as N-methylamide, N-allylamide, N-t-butylamide and the like.
Protecting groups for a sulfonamide group, and reactions and conditions for protecting and deprotecting the sulfonamide group are well known in the art and are disclosed, for example, in Greene and Wuts, “Protective Groups in Organic Synthesis”, John Wiley & Sons (2007), Chapter 7 and references cited therein. For example, a protecting group may protect a sulfonamide group as N-t-butylsulfonamide, N-diphenylmethylsulfonamide, N-benzylsulfonamide and the like. A description of example embodiments of the invention follows.
The following abbreviations have the indicated meanings:
Abbreviation
Meaning
A %
Area percentage
Boc
tert-butoxy carbonyl or t-butoxy carbonyl
(Boc) 2 O
di-tert-butyl dicarbonate
Cbz
Benzyloxycarbonyl
CbzCl
Benzyl chloroformate
c-Pr
cyclopropyl
DAST
diethylaminosulfur trifluoride
DBU
1,8-diazabicyclo[5.4.0]undec-7-ene
DCC
N,N′-dicyclohexylcarbodiimide
DCU
N,N′-dicyclohexylurea
DIAD
diisopropyl azodicarboxylate
DIBAL-H
diisobutylaluminum hydride
DIEA
N,N-diisopropylethylamine
DMAP
4-(dimethylamino)pyridine
DMF
N,N-dimethylformamide
DMPU
1,3-dimethyl-3,4,5,6-tetrahydro-2(1H)-pyrimidinone
2,4-DNP
2,4-dinitrophenylhydrazine
DPTBS
Diphenyl-t-butylsilyl
dr
diastereomer ratio
EDC•HCl, EDCI
1-[3-(dimethylamino)propyl]-3-ethylcarbodiimide
hydrochloride
Equiv
equivalents
EtOAc
ethyl acetate
Fmoc
1-[[(9H-fluoren-9-ylmethoxy)carbonyl]oxy]-
Fmoc-OSu
1-[[(9H-fluoren-9-ylmethoxy)carbonyl]oxy]-2,5-
pyrrolidinedione
h, hr
hour(s)
HOBt
1-hydroxybenzotriazole
HATU
2-(7-Aza-1H-benzotriazole-1-yl)-1,1,3,3-
tetramethyluronium hexafluorophosphate
HBTU
2-(1H-Benzotriazol-1-yl)-1,1,3,3-tetramethyluronium
hexafluorophosphate
KHMDS
potassium hexamethyldisilazane
LAH or LiAlH 4
lithium aluminum hydride
LC-MS
liquid chromatography-mass spectroscopy
LHMDS
lithium hexamethyldisilazane
m-CPBA
meta-chloroperoxybenzoic acid
Me
methyl
MsCl
methanesulfonyl chloride
Min
minute
MS
mass spectrum
NaH
sodium hydride
NaHCO 3
sodium bicarbonate
NaN 3
sodium azide
NaOH
sodium hydroxide
Na 2 SO 4
sodium sulfate
NMM
N-methylmorpholine
NMP
N-methylpyrrolidinone
Pd 2 (dba) 3
tris(dibenzylideneacetone)dipalladium(0)
PE
petroleum ether
Quant
quantitative yield
rt
room temperature
Satd
saturated
SOCl 2
thionyl chloride
SFC
supercritical fluid chromatography
SPA
scintillation proximity assay
SPE
solid phase extraction
TBAF
tetrabutylammonium fluoride
TBS
t-butyldimethylsilyl
TBDPS
t-butyldiphenylsilyl
TBSCl
t-butyldimethylsilyl chloride
TBDPSCl
t-butyldiphenylsilyl chloride
TEA
triethylamine or Et 3 N
TEMPO
2,2,6,6-tetramethyl-1-piperidinyloxy free radical
Teoc
1-[2-(trimethylsilyl)ethoxycarbonyloxy]-
Teoc-OSu
1-[2-(trimethylsilyl)ethoxycarbonyloxy]pyrrolidin-
2,5-dione
T ext
External temperature
T int
Internal temperature
TFA
trifluoroacetic acid
Tlc, TLC
thin layer chromatography
TMS
trimethylsilyl
TMSCl
chlorotrimethylsilane or trimethylsilyl chloride
t R
retention time
TsOH
p-toluenesulfonic acid
EXEMPLIFICATION
Synthesis of Compound 8 of FIG. 1
FIG. 1 shows a preferred synthesis of a specific tertiary alcohol oxazinone compound (compound 8) known to be a 11β-HSD1 inhibitor. Compounds 3 to 8 of FIG. 1 were synthesized as described in Examples 1 to 4.
Example 1
1-Chloro-5-methyl-3-phenyl-hex-5-en-3-ol (3)
To a stirred suspension of magnesium turnings (46.7 g, 1.94 mol) in 1500 mL of THF (KF<100 ppm) was charged 53.0 mL of 1 M DIBAL-H in hexane under nitrogen at room temperature. Then beta-methylallylic chloride (160 g, 1.77 mol) was introduced while maintaining the internal temperature below 30° C. The resulting solution was agitated for 2 h at room temperature. The solution was titrated in the presence of 1.1′-bipyridine to indicate 0.8 M of the corresponding Grignard reagent. To a dry flask containing 307.0 g of anhydrous CeCl 3 (1.25 mol) at room temperature under nitrogen was added 1556.8 mL of the Grignard reagent (0.8 M, 1.25 mol). The resulting slurry was cooled to −10° C. and agitated for 0.5 h. To the slurry was added 200 g of the ketone (1.19 mol) in 200 mL of THF while maintaining the internal temperature below 0° C. After the mixture was stirred for 0.5 h, 1200 mL of 1 M HCl was added to obtain a clear solution while maintaining the internal temperature below 30° C. After the phase cut, the aqueous layer was extracted with EtOAc (500 mL). The combined organic layers were washed with brine and dried over sodium sulfate. Removal of the solvent under vacuum produced the crude product, which was chased with THF to achieve K<500 ppm. The crude product (306 g, 83 wt %, 95% yield) was used directly for subsequent coupling. Analytical data for 3: 1 H-NMR spectroscopy (500 MHz, CDCl 3 ) δ 7.38-7.37 (d. J=7.8 Hz, 2H), 7.33 (t, J=7.9 Hz, 2H), 7.24 (t, J=7.4 Hz, 1H), 4.91 (s, 1H), 4.76 (s, 1H), 3.57 (ddd, J=5.6, 10.7, and 10.7, 1H), 3.13 (ddd, J=4.7, 10.7 and 10.7 Hz, 1H), 2.66 (d, J=13.3 Hz, 1H), 2.54 (d, J=11.3 Hz, 1H), 2.53 (s, 1H), 2.36 (ddd, J=5.4, 10.6 and 13.9 Hz. 1H), 2.29 (ddd, J=5.6, 11.3 and 13.3 Hz, 1H), 1.29 (s, 3H). 13 C-NMR spectroscopy (125 MHz, CDCl 3 ) δ 144.3, 141.4, 128.0, 126.6, 124.8, 116.1, 74.2, 51.2, 46.0, 39.9, 23.9.
Example 2
1-Bromo-4-((S)-1-isocyanato-ethyl)-benzene (4)
To a 10 L jacketed reactor was charged 241 g of sodium bicarbonate (2.87 mol, 2.30 equiv) and 5 L of deionized water. The resulting solution was agitated for 10-20 min, until the solids dissolved (homogeneous). To the clear solution was charged 250 g (1.25 mol, 1.00 equiv) of (S)-(−)-1-(4-bromophenyl)ethylamine as a solution in 1.00 L of dichloromethane. An additional 4 L of dichloromethane was charged to the reactor. The biphasic solution was agitated and cooled to T int =2-3° C. Triphosgene (126 g, 424 mmol, 0.340 equiv) was charged to the reactor in approximately two equal portions ˜6 min apart. It should be noted that a slight exotherm was noted upon the addition of triphosgene. The resulting murky solution was agitated at T int =2-5° C. for 30 min, at which point HPLC analysis indicates >99 A % conversion (220 nm). The dichloromethane layer was cut and dried with anhydrous sulfate. The resulting solution was passed through a celite plug and concentrated to ˜1.5 L which fine particles of a white solid developed. The solution was filtered and concentrated to a thick oil via reduced pressure to produce 239 g of product (93.7 wt %, 79.4% yield). The material was used in the following coupling without further purification. Analytical data for 4: 1H-NMR spectroscopy (400 MHz, CD2Cl2) δ 7.53 (d, J=11.4 Hz, 2H), 7.26 (d, J=8.2 Hz, 2H), 4.80 (q, J=6.7 Hz, 1H), 1.59 (d, J=6.7 Hz, 3H).
Example 3
(R)-3-[(S)-1-(4-Bromo-phenyl)-ethyl]-6-(2-methyl-allyl)-6-phenyl-perhydro-1,3-oxazin-2-one (6)
To a dried 10 L jacketed reactor under a nitrogen atmosphere was charged 1-chloro-5-methyl-3-phenyl-hex-5-en-3-ol (3, 167 g, 81.7 wt %, 610 mmol, 1.00 equiv), 1-bromo-4-((S)-1-isocyanato-ethyl)-benzene (4, 219 g, 93.7 wt %, 911 mmol, 1.50 equiv), anhydrous tetrahydrofuran (3.00 L), and then 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU, 409 mL, 2.73 mol, 4.50 equiv). The resulting solution was agitated and refluxed (T int =67-69° C., T ext =75° C.) for 19 h, at which point HPLC analysis indicates ˜1 A % (220 nm) of the 1-chloro-5-methyl-3-phenyl-hex-5-en-3-ol (3) remains. The dark solution was cooled to Tint=20-25° C. Two liters of tetrahydrofuran were removed by distillation under reduced pressure. The remaining dark solution was diluted with 4.0 L of ethyl acetate and 1.0 L of hexanes. The resulting solution was washed with 4.0 L of a 1.0 M aqueous solution of hydrogen chloride (note: the wash is slightly exothermic). The aqueous solution was cut and the remaining organic solution was dried with anhydrous sodium sulfate, filtered and then concentrated to an oil via reduced pressure. The resulting material was subjected to flash silica chromatography (5-30% ethyl acetate/hexanes, 1.74 kg of silica) to produce 137.8 g of material (59 wt %, 3.1:1 diastereomeric ratio favoring the desired diastereomer 6, 32.3% yield). The material was used in the following epoxidation without further purification.
Analytical data for (R)-3-[(S)-1-(4-bromo-phenyl)-ethyl]-6-(2-methyl-allyl)-6-phenyl-perhydro-1,3-oxazin-2-one (6): 1H-NMR spectroscopy (500 MHz, CD2Cl2) δ 7.42-7.35 (m, 3H), 7.33-7.31 (m, 2H), 7.25-7.23 (m, 2H), 6.80-6.74 (m, 2), 5.55 (q, J=7.1 Hz, 1H), 5.37-5.36 (m, 1H), 4.89 (s, 1H), 4.69 (s, 1H), 2.96-2.93 (m, 1H), 2.61 (dd, J=13.8 and 26.4 Hz, 2H), 2.37-2.25 (m, 3H), 1.68 (s, 3H), 1.50 (d, J=7.1 Hz, 3H). 13C-NMR spectroscopy (125 MHz, CD2Cl2) δ 152.5, 141.5, 140.1, 138.3, 130.6, 128.1, 128.0, 126.9, 124.4, 120.2, 115.3, 82.4, 52.1, 50.1, 35.6, 29.8, 23.4, 14.5.
Analytical data for (S)-3-[(S)-1-(4-bromo-phenyl)-ethyl]-6-(2-methyl-allyl)-6-phenyl-perhydro-1,3-oxazin-2-one (5): 1H-NMR spectroscopy (400 MHz, CD2Cl2) δ 7.50-7.48 (m, 2H), 7.43-7.39 (m, 2H), 7.35-7.32 (m, 3H), 7.20-7.18 (m, 2H), 5.60 (q, J=7.1 Hz, 1H), 4.85 (s, 1H), 4.66 (s, 1H), 2.73-2.67 (m, 2H), 2.60 (dd, J=13.9 and 19.4 Hz, 2H), 2.28 (dt, J=3.3 and 13.7 Hz, 1H), 2.14-2.05 (m, 1H), 1.66 (s, 3H), 1.24 (d, J=7.2 Hz, 3H). 13C-NMR spectroscopy (100 MHz, CD2Cl2) δ 153.4, 142.5, 141.0, 140.1, 131.8, 129.3, 128.9, 127.8, 125.3, 121.5, 116.3, 83.9, 53.2, 51.0, 36.6, 31.3, 24.3, 15.4.
Example 4
(S)-3-[(S)-1-(4-Bromo-phenyl)-ethyl]-6-(2-hydroxy-2-methyl-propyl)-6-phenyl-perhydro-1,3-oxazin-2-one (8; BI00135541)
To a 1.0 L 2-neck RBF was charged (R)-3-[(S)-1-(4-bromo-phenyl)-ethyl]-6-(2-methyl-allyl)-6-phenyl-perhydro-1,3-oxazin-2-one (6, 135.8 g, 59 wt %, 3.1:1 dr, 193 mmol, 1.00 equiv), dichloromethane (700 mL), and then 3-chloroperbenzoic acid (MCPBA, 70%, 95.3 g, 386 mmol, 2.0 equiv). The resulting solution was agitated at RT (T int =20-25° C.) for 1 h, which HPLC analysis indicates >99 A % (220 nm) conversion. The resulting solution was diluted with 700 mL of methyl tert-butyl ether (MTBE) and washed with 1×500 mL of 30 wt % solution of sodium thiosulfate and 1×500 mL of saturated aqueous solution of sodium bicarbonate. The wash sequence were repeated until the peak on an HPLC trace of the organic solution that corresponds to a HPLC sample peak of MCPBA is <2.5 A % (220 nm), which in this example the wash sequence was repeated 3 times. The resulting organic layer was dried with anhydrous sodium sulfate, filtered and then concentrated to an oil via reduced pressure. The resulting material was diluted with 200 mL of anhydrous tetrahydrofuran and then concentrated to a thick oil via reduced pressure to provide (S)-3-[(S)-1-(4-bromo-phenyl)-ethyl]-6-(2-methyl-oxiranylmethyl)-6-phenyl-perhydro-1,3-oxazin-2-one (7) which was used directly in the following reduction.
To a 2.0 L 3-neck oven-dried RBF was charged the crude (S)-3-[(S)-1-(4-bromo-phenyl)-ethyl]-6-(2-methyl-oxiranylmethyl)-6-phenyl-perhydro-1,3-oxazin-2-one (7) and 750 mL of anhydrous tetrahydrofuran. The resulting solution was agitated and cooled to T int =2-3° C. To the agitated clear solution was charged 1.0 M lithium triethylborohydride in tetrahydrofuran (Super Hydride, 348 mL, 348 mmol, 1.8 equiv). The addition is exothermic and addition controlled to maintain T int =<8° C. The resulting solution was agitated at T int =2-3° C. for 1.5 h and then allowed to warm to T int =10-13° C. over a 2.5 h, which HPLC analysis indicates ˜94 A % (220 nm) conversion. To the agitated solution was charged a solution of hydrogen peroxide (95.7 mL of a 35 wt % aqueous solution diluted with 400 mL of water, 1.08 mol, 5.60 equiv). The addition is highly exothermic and addition controlled to maintain T int =<25° C. The resulting solution was diluted with 1.00 L of methyl tert-butyl ether (MTBE) and washed with 1.00 L of water followed by 500 mL of a ˜30 wt % solution of sodium thiosulfate. The organic solution was dried with anhydrous sodium sulfate, filtered, and then concentrated via reduced pressure. The resulting material was subjected to flash silica chromatography (10-60% ethyl acetate, 600 g of silica) to produce 68 g of material consisting of both diastereomers (1.98:1 dr) and 41 g of the desired diastereomer (>99:1 dr). The material consisting of the mixed fractions was recrystallized from 250 mL of isopropyl acetate (IPAC) and 200 mL of heptane (anti-solvent) to produce upon filtration 31.3 g of product (95.7 A % at 220 nm, 74:1 dr). The two samples were combined to produce 72.3 g of product (83.6% yield for the two step operation). Analytical data for 8: 1H-NMR spectroscopy (400 MHz, CDCl3) δ 7.37-7.29 (m, 5H), 7.25-7.21 (m, 2H), 6.82-6.79 (m, 2H), 5.61 (q, J=6.9 Hz, 1H), 2.83 (ddd, J=2.5, 5.4 and 11.6 Hz, 1H), 2.39 (ddd, J=5.7, 12.0 and 14.1 Hz, 1H), 2.27 (ddd, J=2.6, 4.8 and 14.0 Hz, 1H), 2.21-2.14 (m, 3H), 2.08 (s, 1H), 1.49 (d, J=7.0 Hz, 3H), 1.18 (s, 3H), 1.13 (s, 3H). 13C-NMR spectroscopy (100 MHz, CDCl3) δ 153.2, 142.6, 138.5, 131.6, 129.13, 129.10, 128.0, 125.3, 121.6, 84.2, 71.4, 54.1, 53.3, 36.4, 33.6, 32.1, 30.8, 15.6.
Synthesis of Oxazinones
Reaction of a β-Haloalcohol and an Isocyanate
Example 5
6-allyl-6-(4-fluorophenyl)-3-((S)-1-phenylethyl)-1,3-oxazinan-2-one
Step 1. 1-Chloro-3-(4-fluorophenyl)hex-5-en-3-ol
To a solution of 1,1′-bi-2-naphthol (0.2280 g, 0.80 mmol, 0.26 equiv), CH 2 Cl 2 (5 mL) and titanium(IV) isopropoxide (0.2243 g, 0.79 mmol, 0.26 equiv) were added 2-propanol (3.1620 g, 52.6 mmol, 17 equiv), tetraallylstannane (1.2538 g, 4.43 mmol, 1.43 equiv), and 3-chloro-1-(4-fluorophenyl)propan-1-one (0.5760 g, 3.09 mmol, 1.0 equiv) successively. The reaction mixture was stirred at rt under nitrogen for 22 h. The reaction was quenched with satd aq NH 4 Cl and extracted with EtOAc. The organic layer was dried over Na 2 SO 4 . After the solvents were evaporated, the residue was purified by chromatography on silica gel eluted with hexanes/ethyl acetate to afford 1-chloro-3-(4-fluorophenyl)hex-5-en-3-ol as an oil.
Step 2. 6-Allyl-6-(4-fluorophenyl)-3-((S)-1-phenylethyl)-1,3-oxazinan-2-one
A mixture of 1-chloro-3-(4-fluorophenyl)hex-5-en-3-ol (0.0889 g, 0.39 mmol, 1.0 equiv), (S)-(−)α-methylbenzyl isocyanate (0.0823 g, 0.56 mmol, 1.44 equiv), and DBU (0.1397 g, 0.92 mmol, 2.36 equiv) in THF (2 mL) was heated to reflux for 17 h. After the solvent was removed, the residue was purified by chromatography on silica gel eluted with hexanes/ethyl acetate to give 0.0990 g (75%) of the product as a mixture of diastereomers. Selected fractions contained the individual diastereomers.
Isomer 1: (R)-6-allyl-6-(4-fluorophenyl)-3-((S)-1-phenylethyl)-1,3-oxazinan-2-one. LC-MS Method 1, t R =1.89 min, m/z=340 (M+1). 1 H NMR (CDCl 3 ) 7.36-7.27 (m, 7H), 7.10-7.05 (m, 2H), 5.79-5.67 (m, 2H), 5.09-4.98 (m, 2H), 2.72-2.68 (m, 2H), 2.64-2.53 (m, 2H), 2.22-2.16 (m, 1H), 2.09-2.01 (m, 1H), 1.26 (d, J=7.3 Hz, 3H).
Isomer 2: (S)-6-allyl-6-(4-fluorophenyl)-3-((S)-1-phenylethyl)-1,3-oxazinan-2-one. LC-MS Method 1, t R =1.86 min, m/z=340 (M+1). 1 H NMR (CDCl 3 ) 7.29-7.24 (m, 2H), 7.14-7.08 (m, 3H), 7.05-7.00 (m, 2H), 6.88-6.85 (m, 2H), 5.77-5.63 (m, 2H), 5.10-5.00 (m, 2H), 2.93-2.88 (m, 1H), 2.65-2.52 (m, 2H), 2.32-2.17 (m, 3H), 1.51 (d, J=7.0 Hz, 3H).
Example 6
6-allyl-3-((S)-1-(4-bromophenyl)ethyl)-6-(4-fluorophenyl)-1,3-oxazinan-2-one
Step 1. 1-chloro-3-(4-fluorophenyl)hex-5-en-3-ol
A 250-mL flask was charged with anhydrous CeCl 3 (5.58 g, 22.6 mmol) and THF (40 mL). The mixture was vigorously stirred for 3.5 h at rt. The suspension was then cooled to −78° C. and a solution of allylmagnesium bromide (1.0 M in THF, 21 mL, 21.0 mmol) was added. After stirring for 2 h at −78° C., a solution of 3-chloro-1-(4-fluorophenyl)propan-1-one (2.522 g, 13.5 mmol) in THF (30 mL) was added via cannula. The reaction mixture was allowed to slowly warm to 8° C. while stirring overnight (18 h). The reaction was then quenched with satd aq NaHCO 3 , extracted with EtOAc, and dried over Na 2 SO 4 . After the solvents were evaporated, the residue was purified by chromatography on silica gel eluted with hexanes/ethyl acetate to afford of 1-chloro-3-(4-fluorophenyl)hex-5-en-3-ol (3.0049 g, 97%) as an oil. LC-MS Method 1 t R =1.79 min, m/z 213, 211 (M-OH) + ; 1 H NMR (400 MHz, CDCl 3 ) δ 7.37-7.32 (m, 2H), 7.07-7.02 (m, 2H), 5.57-5.47 (m, 1H), 5.20-5.19 (m, 1H), 5.16 (m, 1H), 3.59-3.52 (m, 1H), 3.24-3.18 (m, 1H), 2.70 (dd, J=13.8, 5.9 Hz, 1H), 2.50 (dd, J=13.8, 8.5 Hz, 1H), 2.29 (t, J=7.9 Hz, 2H), 2.22 (s, 1H); 19 F NMR (376 MHz, CDCl 3 ) δ −116.52 (m).
Step 2. (R)-6-allyl-3-((S)-1-(4-bromophenyl)ethyl)-6-(4-fluorophenyl)-1,3-oxazinan-2-one and (S)-6-allyl-3-((S)-1-(4-bromophenyl)ethyl)-6-(4-fluorophenyl)-1,3-oxazinan-2-one
A mixture of 1-chloro-3-(4-fluorophenyl)hex-5-en-3-ol (0.4129 g, 1.8 mmol, 1.0 equiv), (S)-(−)-1-(4-bromophenyl)ethyl isocyanate (0.5005 g, 2.2 mmol, 1.2 equiv), and DBU (0.7375 g, 4.8 mmol, 2.7 equiv) in THF (10 mL) was heated to reflux for 25 h. The mixture was diluted with EtOAc and washed with 1 N aq HCl. The aqueous phase was extracted with EtOAc (2×). The combined organic phase was dried over Na 2 SO 4 . After the solvents were evaporated, the crude product was directly used in the next step without further purification.
An analytical sample was purified by chromatography on silica gel eluted with hexanes/ethyl acetate to afford the two diastereomers of 6-allyl-3-((S)-1-(4-bromophenyl)ethyl)-6-(4-fluorophenyl)-1,3-oxazinan-2-one.
Isomer 1: (S)-6-allyl-3-((S)-1-(4-bromophenyl)ethyl)-6-(4-fluorophenyl)-1,3-oxazinan-2-one. LC-MS Method 1 t R =2.03 min, m/z 420, 418 (MH + ); 1 H NMR (400 MHz, CDCl 3 ) δ 7.46 (d, J=8.2 Hz, 2H), 7.31-7.28 (m, 2H), 7.17 (d, J=8.2 Hz, 2H), 7.07 (t, J=8.5 Hz, 2H), 5.76-5.66 (m, 2H), 5.10-4.99 (m, 2H), 2.75-2.52 (m, 4H), 2.23-2.19 (m, 1H), 2.08-2.00 (m, 1H), 1.24 (d, J=7.0 Hz, 3H); 19 F NMR (376 MHz, CDCl 3 ) δ −115.07 (m).
Isomer 2: (R)-6-allyl-3-((S)-1-(4-bromophenyl)ethyl)-6-(4-fluorophenyl)-1,3-oxazinan-2-one. LC-MS Method 1 t R =1.98 min, m/z 420, 418 (MH + ); 1 H NMR (400 MHz, CDCl 3 ) δ 7.25-7.20 (m, 4H), 7.05-7.01 (m, 2H), 6.71 (d, J=8.5 Hz, 2H), 5.74-5.64 (m, 1H), 5.58 (q, J=7.0 Hz, 1H), 5.09-4.99 (m, 2H), 2.92-2.87 (m, 1H), 2.63-2.50 (m, 2H), 2.33-2.16 (m, 3H), 1.47 (d, J=7.0 Hz, 3H); 19 F NMR (376 MHz, CDCl 3 ) δ −114.91 (m).
Example 7
6-methyl-6-phenyl-3-m-tolyl-1,3-oxazinan-2-one
Step 1. 2-Phenylpent-4-en-2-ol
To a solution of acetophenone (30 g, 0.25 mol) in dry THF (250 mL) at −78° C. was added dropwise 1M allylmagnesium bromide (1.25 L, 1.25 mol). After addition was complete, the mixture was allowed to stir at rt for 3 h. The reaction was quenched with satd aq NH 4 Cl solution (30 mL). The mixture was extracted with EtOAc (200 mL). The organic layer was washed with brine (30 mL), dried over anhydrous Na 2 SO 4 and concentrated to give 2-phenylpent-4-en-2-ol (40.2 g), which was used for the next step without purification.
Step 2. 3-Phenylbutane-1,3-diol
A solution of 2-phenylpent-4-en-2-ol (74 g, 0.457 mol) in dry CH 2 Cl 2 (1 L) was treated with ozone at −78° C. until the mixture turned blue. The system was then flushed with oxygen to remove excess ozone. NaBH 4 (42.8 g, 1.143 mol) was added to the mixture in portions at −20° C. The mixture was stirred overnight at rt. The mixture was quenched with water and the layers were separated. The aqueous layer was extracted with CH 2 Cl 2 (2×). The organic layers were combined, washed with brine, dried over anhydrous Na 2 SO 4 and concentrated to give 3-phenylbutane-1,3-diol (67.8 g), which was used for the next step without purification.
Step 3. 3-Hydroxy-3-phenylbutyl 4-methylbenzenesulfonate
To a solution of 3-phenylbutane-1,3-diol (68 g, 0.41 mol) in dry CH 2 Cl 2 (500 mL) was added dropwise a solution of TsCl (78 g, 0.41 mol) and triethylamine (71 mL, 0.45 mol) in dry CH 2 Cl 2 (500 mL) at 0° C. The mixture was stirred overnight. The mixture was poured into water and separated. The aqueous layer was extracted with CH 2 Cl 2 (200 mL) twice. The organic layer was combined, washed with brine, dried over anhydrous Na 2 SO 4 and concentrated to give the crude product. The crude product was purified by column chromatography to give 3-hydroxy-3-phenylbutyl 4-methylbenzenesulfonate (62 g, 42%). 1 H NMR (400 MHz, CDCl 3 ): δ=1.55 (s, 3H), 1.93 (w, 1H), 2.19˜2.24 (q, 2H), 2.45 (s, 3H), 3.87˜4.01 (m, 1H), 4.09˜4.16 (m, 1H), 7.19˜7.34 (m, 7H), 7.68˜7.76 (d, 2H).
Step 4. 6-methyl-6-phenyl-3-m-tolyl-1,3-oxazinan-2-one
To a solution of 3-hydroxy-3-phenylbutyl 4-methylbenzenesulfonate (1 g, 3.12 mmol) and DBU (1.4 g, 9.26 mmol) in CH 2 Cl 2 (15 mL) was added a solution of 3-methylphenyl isocyanate (623 mg, 4.68 mmol) in CH 2 Cl 2 (5 mL) at 0° C. over 0.5 h. The mixture was stirred at rt overnight. The mixture was concentrated to give the crude product, which was purified by column chromatography and then by preparative HPLC to afford 6-methyl-6-phenyl-3-m-tolyl-1,3-oxazinan-2-one. LC-MS Method 2, t R =2.706 min, m/z=282. 1 H NMR (CDCl 3 ) 1.75 (s, 3H), 2.30 (s, 3H), 2.35-2.50 (m, 2H), 3.30 (m, 1H), 3.50 (m, 1H), 6.95 (m, 2H), 7.05 (m, 1H), 7.20-7.30 (m, 1H), 7.35 (m, 1H), 7.42-7.50 (m, 4H).
Step 5. Enantiomers of 6-methyl-6-phenyl-3-m-tolyl-1,3-oxazinan-2-one
Chiral preparative SFC using a ChiralPak-AD, 400×25 mm I.D, 20 μm (Daicel Chemical Industries, Ltd) column maintained at 35 C eluted with 70:30 supercritical CO 2 /0.1% diethylamine in MeOH at a flow rate of 70 mL min −1 and a nozzle pressure of 100 bar afforded two isomers.
Isomer 1 (90 mg) gave the following spectral data: 1 H NMR (400 MHz, CDCl 3 ): δ=1.62 (m, 1H), 1.76 (s, 3H), 2.31 (s, 3H), 2.48 (m, 2H), 3.28 (m, 1H), 3.50 (m, 1H), 6.95 (m, 1H), 7.04 (m, 1H), 7.23 (t, 1H), 7.35 (m, 1H), 7.44 (m, 4H);
Isomer 2 (100 mg) gave the following spectral data: (400 MHz, CDCl 3 ): δ=1.62 (m, 1H), 1.76 (s, 3H), 2.31 (s, 3H), 2.48 (m, 2H), 3.28 (m, 1H), 3.50 (m, 1H), 6.95 (m, 1H), 7.04 (m, 1H), 7.23 (t, 1H), 7.35 (m, 1H), 7.44 (m, 4H).
Example 8
6-allyl-3-((S)-1-cyclohexylethyl)-6-(4-fluorophenyl)-1,3-oxazinan-2-one
1-chloro-3-(4-fluorophenyl)hex-5-en-3-ol (126 mg, 0.55 mmol), (S)-(+)-1-cyclohexylethyl isocyanate (160 mg, 1.44 equiv.) and proton sponge (271 mg, 2.3 equiv.) were dissolved in dry THF (5 mL) and heated to reflux for 3 h. The mixture was then cooled to 0° C. and NaH (22 mg, 1.0 equiv.) was added slowly. After 5 min, the mixture was heated to reflux overnight. LC-MS showed the reaction was complete. The mixture was diluted with EtOAc (50 mL) and washed with 1% aq HCl (2×15 mL), satd aq NaHCO 3 (10 mL) and brine (10 mL), and dried over Na 2 SO 4 . After filtration and concentration, the residue was purified by chromatography on a 12-g silica cartridge eluted with a 10-45% EtOAc in hexanes gradient to afford two isomeric products.
Isomer 1: (R)-6-allyl-3-((S)-1-cyclohexylethyl)-6-(4-fluorophenyl)-1,3-oxazinan-2-one (57.5 mg, 30%). LC-MS Method 1, t R =2.05 min, m/z=346. 1 H NMR (CDCl 3 ) 7.29 (m, 2H), 7.02 (m, 2H), 5.70 (m, 1H), 5.05 (dd, 2H), 3.94 (m, 1H), 3.06 (m, 1H), 2.68-2.49 (m, 3H), 2.33 (m, 1H), 2.14 (m, 1H), 1.17 (d, 3H), 0.78 (m, 2H)
Isomer 2: (S)-6-allyl-3-((S)-1-cyclohexylethyl)-6-(4-fluorophenyl)-1,3-oxazinan-2-one (56 mg, 29%). LC-MS Method 1, t R =2.06 min, m/z=346. 1 H NMR (CDCl 3 ) 7.27 (m, 2H), 7.03 (t, 2H), 5.71 (m, 1H), 5.05 (dd, 2H), 3.95 (m, 1H), 2.92 (m, 1H), 2.72 (m, 1H), 2.57 (m, 2H), 2.22 (m, 2H), 1.49 (d, 1H), 1.32 (m, 1H), 0.86 (d, 3H).
Example 9
6-(3-hydroxypropyl)-6-phenyl-3-(2-phenylcyclopropyl)-1,3-oxazinan-2-one
Step 1
To a solution of 2-phenylcyclopropanecarboxylic acid (1.0 g, 6.17 mmol) in dry toluene (20 mL) was added triethylamine (934 mg, 9.26 mmol) and DPPA (2.0 g, 7.41 mmol) under N 2 , and the reaction mixture was refluxed for 3 h. The solution was concentrated to give (2-isocyanatocyclopropyl)benzene (800 mg), which was used for the next step without further purification.
Step 2
To a solution of (2-isocyanatocyclopropyl)benzene (800 mg, 5.03 mmol) in THF (15 mL) was added DBU (1.61 g, 10.48 mmol) and 1-chloro-3-phenylhex-5-en-3-ol (880 mg, 4.19 mmol), and the mixture was refluxed overnight. The solution was diluted with EtOAc, and washed with 1 N HCl (2×15 mL). The aqueous phase was extracted with EtOAc. The combined organic layers were washed with brine, dried over Na 2 SO 4 , filtered and concentrated to give crude product, which was purified by preparative TLC to afford 6-allyl-6-phenyl-3-(2-phenylcyclopropyl)-1,3-oxazinan-2-one (100 mg, 6%). 1 H NMR (CDCl 3 ): 1.05-1.21 (m, 3H), 1.36-1.42 (m, 1H), 2.13-2.34 (m, 1H), 2.39-2.61 (m, 2H), 2.92-3.15 (m, 1H), 3.76-4.01 (m, 1H), 4.95-5.10 (m, 2H), 5.42-5.73 (m, 1H), 6.95-6.99 (m, 1H), 7.10-7.24 (m, 10H).
Step 3
To a solution of 6-allyl-6-phenyl-3-(2-phenylcyclopropyl)-1,3-oxazinan-2-one (200 mg, 0.60 mmol) in dry THF (5 mL) was added dropwise 1 M of BH 3 /THF (1.8 mL, 1.8 mmol) at 0° C. under N 2 . After stirring at rt for 2 h, the reaction mixture was cooled to 0° C. again, and water (0.1 mL), 3 M of aqueous NaOH solution (0.1 mL), and 30% H 2 O 2 (0.3 mL) were added sequentially. After the mixture was stirred at rt for another 2 h, 1 N aqueous HCl (0.5 mL) was added. The mixture was extracted with EtOAc. The organic layer was washed with brine, dried over Na 2 SO 4 , filtered and concentrated to give the crude product, which was purified by preparative TLC followed by preparative HPLC to afford two isomers.
Isomer 1 (20 mg, 9%): LC-MS Method 3 t R =1.151, min, m/z=352.2; 1 H NMR (CDCl 3 ) 0.83 (m, 2H), 1.12 (m, 1H), 1.23 (m, 4H), 1.68 (m, 1H), 1.97 (m, 2H), 2.16 (m, 1H), 2.21 (m, 1H), 2.84 (m, 1H), 3.13 (m, 1H), 3.52 (m, 2H), 4.14 (m, 1H), 7.03 (m, 2H), 7.11 (m, 1H), 7.17 (m, 2H), 7.29 (m, 4H), 7.46-7.63 (m, 1H).
Isomer 2 (15 mg, 7%): LC-MS Method 3 t R =1.149, min, m/z=352.2; 1 H NMR (CDCl 3 ) 0.85 (m, 2H), 1.11 (m, 1H), 1.26 (m, 3H), 1.67 (m, 2H), 1.96 (m, 2H), 2.18 (m, 1H), 2.27 (m, 1H), 2.83 (m, 1H), 3.13 (m, 1H), 3.52 (m, 2H), 4.15 (m, 1H), 7.02 (m, 2H), 7.11 (m, 1H), 7.15 (m, 2H), 7.26 (m, 3H), 7.29 (m, 2H), 7.46-7.63 (m, 1H).
Example 10
(R)-3-((S)-1-(4-bromophenyl)propyl)-6-(3-hydroxypropyl)-6-phenyl-1,3-oxazinan-2-one
Step 1
To a solution of (S)-1-phenylpropan-1-amine (3.00 g, 14 mmol) in the mixture of methylene chloride (50 mL) and saturated NaHCO 3 (50 mL) was added triphosgene (1.40 g, 4.60 mmol) at 0° C. The mixture was stirred for 15 minutes. The organic phase was separated, dried and concentrated to give (S)-(1-isocyanatopropyl)benzene (3.0 g, 88%). 1 H NMR (CDCl 3 ): δ=0.93 (q, 3H), 1.81 (m, 2H), 4.50 (m, 1H), 7.13 (m, 2H), 7.22 (m, 1H), 7.50 (m, 2H).
Step 2
A mixture of (S)-(1-isocyanatopropyl)benzene (3.0 g, 12.5 mmol), 1-chloro-3-phenylhex-5-en-3-ol (3.6 g, 12.5 mmol) and DBU (3.80 g, 25 mmol) in tetrahydrofuran (20 mL) was heated to reflux overnight. The mixture was washed by 1 N HCl and extracted with EtOAc. The organic phase was concentrated to give the crude product which was purified by column chromatography to give (R)-6-allyl-3-((S)-1-(4-bromophenyl)propyl)-6-phenyl-1,3-oxazinan-2-one (1.0 g, 20%). 1 H NMR (400 MHz, CDCl 3 ): δ=0.92 (t, 3H), 1.72-2.00 (m, 4H), 2.06-2.31 (m, 4H), 2.53 (m, 2H), 2.82 (m, 1H), 4.99 (m, 2H), 5.32 (m, 1H), 5.69 (m, 1H), 6.72 (m, 1H), 7.12 (m, 4H), 7.25 (m, 4H).
Step 3
To a solution of (R)-6-allyl-3-((S)-1-(4-bromophenyl)propyl)-6-phenyl-1,3-oxazinan-2-one (100 mg, 0.242 mmol) in tetrahydrofuran (10 mL) was added BH 3 THF (3 mL, 1 mol/L) at 0° C. under nitrogen. The formed mixture was stirred for 2 h. Then the reaction was quenched by water, followed by 3 mol/L NaOH and H 2 O 2 (3 mL). The PH of the mixture was adjusted to <7 with 5% HCl. The organic phase was separated, extracted by EtOAc, and concentrated to give the crude product, which was purified by preparative HPLC to give (R)-3-((S)-1-(4-bromophenyl)propyl)-6-(3-hydroxypropyl)-6-phenyl-1,3-oxazinan-2-one (15 mg, 15%). LC-MS Method 3 t R =1.36, min, m/z=432, 434; 1 H NMR (CDCl 3 ): δ=0.99 (t, 3H), 1.29 (m, 1H), 1.63 (m, 1H), 1.98 (m, 4H), 2.20-2.42 (m, 2H), 2.48 (m, 1H), 3.08 (m, 1H), 3.49 (m, 1H), 5.30 (m, 1H), 6.92 (m, 2H), 7.26 (m, 4H), 7.35 (m, 2H).
Example 11
(R)-3-((R)-1-(2′,4′-difluorobiphenyl-4-yl)ethyl)-6-(4-fluorophenyl)-6-(2-hydroxyethyl)-1,3-oxazinan-2-one
Step 1
TFAA (134 mL, 948 mmol) was dissolved in CH 2 Cl 2 (600 mL) and cooled in an ice water bath. A solution of (S)-1-phenylpropan-1-amine (112.8 g, 930 mmol) in CH 2 Cl 2 (200 mL) was added dropwise and then the ice bath was removed. The reaction mixture was stirred for 3 hrs at ambient temperature. Then the above mixture was cooled in an ice bath and MsOH (160 mL, 2.5 mol) was added dropwise followed by DBDMH (130 g, 454 mmol). The reaction mixture was left stirring overnight at rt and then quenched with water and brine. The combined organic phases were dried over NaSO 4 , filtered and concentrated to give (R)—N-(1-(4-bromophenyl)ethyl)-2,2,2-trifluoroacetamide (120 g, 44%) as a off-white solid. 1 H NMR (CDCl 3 ): 1.56 (m, 3H), 1.86 (m, 2H), 5.11 (m, 1H), 6.63 (m, 1H), 7.18 (m, 2H), 7.50 (m, 2H).
Step 2
(R)—N-(1-(4-bromophenyl)ethyl)-2,2,2-trifluoroacetamide (20 g, 68 mmol) was dissolved in methanol (200 mL) and cooled in an ice-water bath. Then aqueous NaOH (2 M, 100 mL) was added to the above mixture. The reaction mixture was stirred overnight at ambient temperature. The reaction mixture was concentrated and then partitioned between CH 2 Cl 2 and water. The aqueous layer was extracted with addition CH 2 Cl 2 and the combined organic phases were dried over Na 2 SO 4 , filtered and concentrated to give (R)-1-(4-bromophenyl)ethan amine (9.8 g, 73%). 1 H NMR (DMSO): 1.19 (m, 3H), 3.92 (m, 1H), 7.28 (m, 2H), 7.42 (m, 2H).
Step 3
To a solution of (S)-1-(4-bromophenyl)propan-1-amine (5 g, 25 mmol) in CH 2 Cl 2 (10 mL) was added saturated aqueous NaHCO 3 (10 mL) and then triphosgene (2.45 g, 8 mmol) at 0. Then the reaction mixture was stirred for 15 minutes at 0° C. under nitrogen. The reaction mixture was extracted with CH 2 Cl 2 twice. The combined organic phases were dried over Na 2 SO 4 , filtered and concentrated to afford (R)-1-bromo-4-(1-isocyanatoethyl)benzene (2.5 g, 44%), which was used for the next step without purification.
Step 4
To a solution of (R)-1-bromo-4-(1-isocyanatoethyl)benzene (2.5 g, 11 mmol) in THF anhydrous (40 mL) was added 1-chloro-3-(4-fluorophenyl)hex-5-en-3-ol (1.69 g, 7 mmol) and DBU (5.68 g, 33 mmol) at ambient temperature and the reaction mixture was refluxed overnight. The reaction mixture was extracted with 1 N aq HCl and EtOAc. The combined organic phases were dried over Na 2 SO 4 , filtered and concentrated to afford the residue, which was purified by column chromatography to give two isomers.
Isomer 1: (R)-6-allyl-3-((R)-1-(4-bromophenyl)ethyl)-6-(4-fluorophenyl)-1,3-oxazinan-2-one (334 mg, 7%). 1 H NMR (CD 3 OD): 1.50 (m, 3H), 2.16-2.38 (m, 2H), 2.46 (m, 1H), 2.60 (m, 2H), 3.10 (m, 1H), 5.05 (m, 2H), 5.48 (m, 1H), 5.66 (m, 1H), 6.82 (m, 2H), 7.08 (m, 2H), 7.26 (m, 4H).
Isomer 2: (S)-6-allyl-3-((R)-1-(4-bromophenyl)ethyl)-6-(4-fluorophenyl)-1,3-oxazinan-2-one.
Step 5
A solution of (R)-6-allyl-3-((R)-1-(4-bromophenyl)ethyl)-6-(4-fluorophenyl)-1,3-oxazinan-2-one (334 mg, 0.80 mmol) in dry CH 2 Cl 2 (20 mL) was treated with ozone at −78° C. until the reaction mixture became blue. Then the mixture was flushed with oxygen to remove excess ozone. To the above mixture was added NaBH 4 (273 mg, 7 mmol) at 0° C. and the reaction mixture was stirred for 4 hrs at ambient temperature under nitrogen. The reaction mixture was washed with water and then extract with CH 2 Cl 2 twice. The combined organic phases were dried over NaSO 4 , filtered and concentrated to give the residue, which was purified by preparative HPLC to afford (S)-3-((R)-1-(4-bromophenyl)ethyl)-6-(4-fluorophenyl)-6-(2-hydroxyethyl)-1,3-oxazinan-2-one (118 mg, 35%). 1 H NMR (CD3OD): 1.50 (m, 3H), 2.12 (m, 2H), 2.29 (m, 2H), 2.50 (m, 1H), 3.10 (m, 1H), 3.33 (m, 1H), 3.68 (m, 1H), 4.56 (m, 1H), 5.50 (m, 1H), 6.86 (m, 2H), 7.10 (m, 2H), 7.30 (m, 4H).
Step 6
To a solution of (S)-3-((R)-1-(4-bromophenyl)ethyl)-6-(4-fluorophenyl)-6-(2-hydroxyethyl)-1,3-oxazinan-2-one (109 mg, 0.26 mmol), 2,4-difluorophenylboronic acid (49 mg, 0.31 mmol) and Pd(PPh 3 ) 4 (30 mg, 0.03 mmol) in dioxane (8 mL) was added a solution of CsCO 3 (2 M, 1 mL) at 0. Then the reaction mixture was refluxed overnight under nitrogen. The reaction mixture was washed with water and then extract with CH 2 Cl 2 twice. The combined organic phases were dried over Na 2 SO 4 , filtered and concentrated to give the residue, which was purified by preparative HPLC to afford (S)-3-((R)-1-(2′,4′-difluorobiphenyl-4-yl)ethyl)-6-(4-fluorophenyl)-6-(2-hydroxyethyl)-1,3-oxazinan-2-one (49 mg, 42%). LC-MS Method 3 tR=1.41, min, m/z=456; 1 H NMR (CD 3 OD): 1.55 (m, 3H), 2.12 (m, 2H), 2.22-2.46 (m, 3H), 2.52 (m, 1H), 3.12 (m, 1H), 3.33 (m, 1H), 3.68 (m, 1H), 5.56 (m, 1H), 7.08 (m, 6H), 7.08 (m, 2H), 7.35 (m, 5H). 443-155-3.
(R)-3-((R)-1-(2′,4′-difluorobiphenyl-4-yl)ethyl)-6-(4-fluorophenyl)-6-(2-hydroxyethyl)-1,3-oxazinan-2-one was prepared from (S)-6-allyl-3-((R)-1-(4-bromophenyl)ethyl)-6-(4-fluorophenyl)-1,3-oxazinan-2-one following procedures analogous to those described in Steps 5 and 6 immediately above. LC-MS Method 3 t R =1.47, min, m/z=456; 1 H NMR (CD 3 OD) 1.35 (m, 3H), 2.18 (m, 2H), 2.40 (m, 1H), 2.51 (m, 1H), 2.82 (m, 2H), 3.33 (m, 1H), 3.71 (m, 1H), 4.22-4.48 (m, 1H), 5.62 (m, 1H), 7.03 (m, 2H), 7.18 (m, 2H), 7.38 (m, 4H), 7.50 (m, 3H).
Example 12
(R)-3-((S)-1-(4-bromophenyl)ethyl)-6-(3-hydroxypropyl)-6-phenyl-1,3-oxazinan-2-one
Step 1
To a solution of (S)-1-(4-bromophenyl)ethanamine (40 g, 0.2 mol) in methylene chloride (600 mL) and satd aq NaHCO 3 (600 mL) was added triphosgene (27 g, 0.025 mol) at 0° C. The mixture was stirred for 15 min. The organic phase was separated, dried and concentrated to give 1-bromo-4-(1-isocyanato-ethyl)-benzene (35 g, crude).
Step 2
A mixture of 1-chloro-3-phenyl-hex-5-en-3-ol (27.5 g, 130 mmol), (S)-(−)-1-(-bromophenyl)ethyl isocyanate (35 g, 160 mmol), and DBU (80 g, 325 mmol) in THF (400 mL) was heated to reflux for 25 h. The mixture was diluted with EtOAc and washed with 1 N aq HCl. The aqueous phase was extracted with EtOAc (3×). The combined organic phase was dried over Na 2 SO 4 . After the solvents were evaporated, the crude product was purified by column chromatography to give (R)-6-allyl-3-((S)-1-(4-bromophenyl)ethyl)-6-phenyl-1,3-oxazinan-2-one (30 g, yield 45%).
Step 3
The title compound was prepared from (R)-6-allyl-3-((S)-1-(4-bromophenyl)ethyl)-6-phenyl-1,3-oxazinan-2-one following a procedure analogous to that described in Example 78. LC-MS Method 2 t R =1.36 min, m/z=440.1; 1 H NMR (CDCl 3 ) 1.26-1.39 (m, 1H), 1.42 (d, 3H), 1.58-1.71 (m, 1H), 1.85-1.95 (m, 2H), 2.11-2.45 (m, 3H), 2.79 (m, 1H), 3.52 (m, 2H), 5.54 (m, 1H), 6.67 (d, 2H), 7.12-7.31 (m, 7H).
Synthesis of Biaryls Via Suzuki Synthesis
Example 13
3-(biphenyl-3-yl)-6-methyl-6-phenyl-1,3-oxazinan-2-one
To a solution of 3-(3-bromophenyl)-6-methyl-6-phenyl-1,3-oxazinan-2-one (50 mg, 0.14 mmol) and phenylboronic acid (35 mg, 0.29 mmol) in THF (2 mL) was added a solution of NaHCO 3 (31 mg, 0.29 mmol) in H 2 O (2 mL) followed by Pd(PPh 3 )Cl 2 (9 mg, 0.01 mmol). The mixture was refluxed overnight. The mixture was concentrated to give the crude product, which was purified by column chromatography, followed by preparative HPLC to afford 3-(biphenyl-3-yl)-6-methyl-6-phenyl-1,3-oxazinan-2-one (10 mg, 20%). 1 H NMR: (400 MHz, CDCl 3 ): δ 1.71 (s, 3H), 2.40 (m, 1H), 2.48 (m, 1H), 3.31 (m, 1H), 3.54 (m, 1H), 7.08 (m, 1H), 7.30 (m, 3H), 7.7.32-7.42 (m, 8H), 7.46 (m, 2H). LC-MS Method 3, t R =1.362 min, m/z=344. 1 H NMR (CDCl 3 ) 1.75 (s, 3H), 2.32-2.43 (m, 1H), 2.50 (m, 1H), 3.20 (m, 1H), 3.52 (m, 1H), 7.10 (d, 1H), 7.25-7.45 (m, 11H), 7.50 (d, 2H).
Example 14
6-allyl-3-(2′,4′-difluorobiphenyl-3-yl)-6-phenyl-1,3-oxazinan-2-one
Step 1. 6-allyl-3-(2′,4′-difluorobiphenyl-3-yl)-6-phenyl-1,3-oxazinan-2-one
To a solution of 6-allyl-3-(3-bromophenyl)-6-phenyl-1,3-oxazinan-2-one (50 mg, 0.134 mmol) and 2,4-difluorophenylboronic acid (40 mg, 0.215 mmol), K 2 CO 3 (0.5 mL, 2 M) in 1,4-dioxane (1.5 ml) was slowly added Pd(Ph 3 ) 2 Cl 2 (10 mg, 20%) at 0° C. under N 2 . The mixture was refluxed overnight. The mixture was concentrated to give the crude product, which was purified by TLC and preparative HPLC to afford 6-allyl-3-(2′,4′-difluorobiphenyl-3-yl)-6-phenyl-1,3-oxazinan-2-one (10 mg, 18%). 1 H NMR (400 MHz, CDCl 3 ): δ=2.40 (m, 2H), 2.55-2.72 (m, 2H), 3.26 (m, 1H), 3.47 (m, 1H), 5.05 (m, 2H), 5.76 (m, 1H), 6.76-6.90 (m, 2H), 7.04 (m, 1H), 7.28 (m, 4H), 7.36 (m, 2H).
Example 15
6-(2-aminoethyl)-3-(2′,4′-difluorobiphenyl-3-yl)-6-phenyl-1,3-oxazinan-2-one
Step 1. 3-(2′,4′-difluorobiphenyl-3-yl)-6-(2-hydroxyethyl)-6-phenyl-1,3-oxazinan-2-one
To a solution of 3-(3-bromophenyl)-6-(2-hydroxyethyl)-6-phenyl-1,3-oxazinan-2-one (200 mg, 0.538 mmol), 4-fluorophenylboronic acid (128 mg, 0.806 mmol), and aq. K 2 CO 3 (1 mL, 2 M) in 1,4-dioxane (3 ml) was slowly added Pd(Ph 3 ) 2 Cl 2 (20 mg, 10%) at 0° C. under N 2 . The mixture was refluxed overnight. The mixture was concentrated to give the crude product, which was purified by TLC and preparative HPLC to afford 3-(2′,4′-difluorobiphenyl-3-yl)-6-(2-hydroxyethyl)-6-phenyl-1,3-oxazinan-2-one (200 mg, 91%). 1 H-NMR (400 MHz, CDCl 3 ): δ=2.12-2.35 (m, 2H), 2.51 (m, 2H), 3.26 (m, 1H), 3.47-3.6 (m, 2H), 4.25 (m, 1H), 6.83 (m, 2H), 7.06 (m, 1H), 7.26-7.51 (m, 8H).
Step 2. 2-(3-(2′,4′-difluorobiphenyl-3-yl)-2-oxo-6-phenyl-1,3-oxazinan-6-yl)ethyl methanesulfonate
To a solution of 3-(2′,4′-difluorobiphenyl-3-yl)-6-(2-hydroxyethyl)-6-phenyl-1,3-oxazinan-2-one (200 mg, 0.49 mmol) in dry CH 2 Cl 2 (4 mL) was added Et 3 N (0.234 mL, 1.46 mmol) at 0˜−5° C. A solution of methanesulfonyl chloride (67 mg, 0.59 mmol) in dry CH 2 Cl 2 (1 mL) was added dropwise at the same temperature. After addition, the mixture was allowed to warm to rt gradually. When the reaction was complete, water (10 mL) was added and the mixture was extracted with CH 2 Cl 2 (3×10 mL). The combined organic layers were washed with 10% aq citric acid, satd aq NaHCO 3 and brine, then dried over Na 2 SO 4 , filtered and concentrated to give 2-(3-(2′,4′-difluorobiphenyl-3-yl)-2-oxo-6-phenyl-1,3-oxazinan-6-yl)ethyl methanesulfonate (230 mg, 97%), which was used in the next step without purification.
Step 3. 6-(2-azidoethyl)-3-(2′,4′-difluorobiphenyl-3-yl)-6-phenyl-1,3-oxazinan-2-one
To a solution of 2-(3-(2′,4′-difluorobiphenyl-3-yl)-2-oxo-6-phenyl-1,3-oxazinan-6-yl)ethyl methanesulfonate (230 mg, 0.47 mmol) in anhydrous DMF (5 mL) was added NaN 3 (92 mg, 1.42 mmol). The reaction mixture was heated to 70° C. overnight. The reaction mixture was cooled to rt and diluted with EtOAc (30 mL), and water (20 ml). The organic phase was washed with water (3×20 mL), dried over Na 2 SO 4 and evaporated to give 6-(2-azidoethyl)-3-(2′,4′-difluorobiphenyl-3-yl)-6-phenyl-1,3-oxazinan-2-one (100 mg, 49%).
Step 4. 3-(2′,4′-difluorobiphenyl-3-yl)-6-(2-hydroxyethyl)-6-phenyl-1,3-oxazinan-2-one
To a solution of 6-(2-azidoethyl)-3-(2′,4′-difluorobiphenyl-3-yl)-6-phenyl-1,3-oxazinan-2-one (100 mg, 0.23 mmol) in 20:1 THF/H 2 O (3 mL) was added PPh 3 (72 mg, 0.28 mmol). The reaction mixture was stirred at rt overnight. The solvent was removed under reduced pressure, and the residue was purified by column chromatography on silica gel to afford 6-(2-aminoethyl)-3-(2′,4′-difluorobiphenyl-3-yl)-6-phenyl-1,3-oxazinan-2-one (30 mg, 31%). 1 H NMR (400 MHz, CDCl 3 ): δ=2.20-2.51 (m, 2H), 2.51-2.60 (m, 2H), 2.72 (m, 1H), 3.00 (m, 1H), 3.24 (m, 1H), 3.53 (m, 1H), 6.85-6.99 (m, 2H), 7.14 (m, 1H), 7.31-7.50 (m, 8H).
Example 16
6-allyl-3-((S)-1-(2′,4′-difluorobiphenyl-4-yl)ethyl)-6-(4-fluorophenyl)-1,3-oxazinan-2-on
Step 1. 6-allyl-3-((S)-1-(2′,4′-difluorobiphenyl-4-yl)ethyl)-6-(4-fluorophenyl)-1,3-oxazinan-2-one
To a solution of 6-allyl-3-((S)-1-(4-bromophenyl)ethyl)-6-(4-fluorophenyl)-1,3-oxazinan-2-one (0.3860 g, 0.92 mmol, 1.0 equiv) in THF (10 mL) were added, under a nitrogen atmosphere, 2,4-difluorophenylboronic acid (0.2708 g, 1.71 mmol, 1.86 equiv), 2 M aq Na 2 CO 3 (8 mL), and (Ph 3 P) 2 PdCl 2 (0.0308 g, 0.0438 mmol, 0.047 equiv). The mixture was stirred for 2 d at 100° C. Brine was then added, the mixture was extracted with Et 2 O (3×), and the combined ether extracts were dried over Na 2 SO 4 . After the solvents were evaporated, the crude product was directly used in the next step without further purification. LC-MS t R =2.13, 2.17 min in 3 min chromatography, m/z 452 (MH + ).
Analytical samples were separated by silica gel chromatography.
Isomer 1: (S)-6-allyl-3-((S)-1-(2′,4′-difluorobiphenyl-4-yl)ethyl)-6-(4-fluorophenyl)-1,3-oxazinan-2-one. LC-MS Method 1, t R =2.17 min, m/z=452. 1 H NMR (CDCl 3 ) 7.47 (d, J=8.2 Hz, 2H), 7.42-7.30 (m, 5H), 7.08 (t, J=8.2 Hz, 2H), 6.98-6.88 (m, 2H), 5.82-5.68 (m, 2H), 5.08 (d, J=10.2 Hz, 1H), 5.02 (d, J=17.0 Hz, 1H), 2.78-2.71 (m, 2H), 2.66-2.54 (m, 2H), 2.25-2.20 (m, 1H), 2.13-2.05 (m, 1H), 1.30 (d, J=7.0 Hz, 3H).
Isomer 2: (R)-6-allyl-3-((S)-1-(2′,4′-difluorobiphenyl-4-yl)ethyl)-6-(4-fluorophenyl)-1,3-oxazinan-2-one. LC-MS Method 1, t R =2.13 min, m/z=452. 1 H NMR (CDCl 3 ) 7.33-7.23 (m, 5H), 7.03 (t, J=8.2 Hz, 2H), 6.96-6.86 (m, 4H), 5.77-5.67 (m, 2H), 5.10 (d, J=10.3 Hz, 1H), 5.04 (d, J=17.3 Hz, 1H), 2.99-2.94 (m, 1H), 2.66-2.54 (m, 2H), 2.41-2.34 (m, 1H), 2.30-2.17 (m, 2H), 1.55 (d, J=7.0 Hz, 3H).
Example 17
3-((S)-1-(2′,4′-difluorobiphenyl-4-yl)propyl)-6-(4-fluorophenyl)-6-(2-hydroxyethyl)-1,3-oxazinan-2-one
To a solution of (S)-3-((S)-1-(4-bromophenyl)propyl)-6-(4-fluorophenyl)-6-(2-hydroxy ethyl)-1,3-oxazinan-2-one (60 mg, 0.14 mmol), 2,4-difluorophenylboronic acid (26 mg, 0.17 mmol) and Pd(PPh 3 ) 4 (16 mg, 0.01 mmol) in dioxane (5 mL) was added a solution of CsCO 3 (2 M, 1 mL) at 0° C. Then the reaction mixture was refluxed overnight under nitrogen. The reaction mixture was washed with water and then extract with CH 2 Cl 2 twice. The combined organic phases were dried over Na 2 SO 4 , filtered and concentrated to give the residue, which was purified by preparative HPLC to afford (S)-3-((S)-1-(2′,4′-difluorobiphenyl-4-yl) propyl)-6-(4-fluorophenyl)-6-(2-hydroxyethyl)-1,3-oxazinan-2-one (17 mg, 26%). 1 H NMR (CD 3 OD): 0.96 (m, 3H), 2.01 (m, 2H), 2.12 (m, 2H), 2.30 (m, 2H), 2.48 (m, 1H), 3.10 (m, 1H), 3.33 (m, 1H), 3.65 (m, 1H), 5.38 (m, 1H), 7.02 (m, 4H), 7.08 (m, 2H), 7.28 (m, 4H), 7.42 (m, 1H). 443-114-3.
(R)-3-((S)-1-(2′,4′-difluorobiphenyl-4-yl) propyl)-6-(4-fluorophenyl)-6-(2-hydroxyethyl)-1,3-oxazinan-2-one was prepared from (R)-3-((S)-1-(4-bromophenyl)propyl)-6-(4-fluorophenyl)-6-(2-hydroxy ethyl)-1,3-oxazinan-2-one following a procedure analogous to that described immediately above. 1 H NMR (CD 3 OD): 0.62 (m, 3H), 1.76 (m, 1H), 1.92 (m, 1H), 2.12 (m, 3H), 2.56 (m, 1H), 2.78 (m, 1H), 2.89 (m, 1H), 3.33 (m, 1H), 3.71 (m, 1H), 5.38 (m, 1H), 7.05 (m, 2H), 7.16 (m, 2H), 7.44 (m, 7H).
Example 18
(S)-3-((S)-1-(4′-fluorobiphenyl-4-yl)ethyl)-6-(2-hydroxyethyl)-6-(thiophen-2-yl)-1,3-oxazinan-2-one
Step 1
Pd(PPh 3 ) 2 Cl 2 (100 mg) was added to the solution of (R)-6-allyl-3-((S)-1-(4-bromophenyl)ethyl)-6-(thiophen-2-yl)-1,3-oxazinan-2-one (1.0 g, 2.5 mmol), 4-fluorophenylboronic acid (420 mg, 3.0 mmol) in 1,4-dioxane. Cs 2 CO 3 (5 mL) was slowly added. The mixture was heated to reflux for 2 h. The mixture was quenched with water and separated, extracted with EtOAc twice, dried over anhydrous Na 2 SO 4 and concentrated to afford the residue, which was purified by TLC to give (R)-6-allyl-3-((S)-1-(4′-fluorobiphenyl-4-yl)ethyl)-6-(thiophen-2-yl)-1,3-oxazinan-2-one (768 mg, 73%).
Step 2
To a solution of (R)-6-allyl-3-((S)-1-(4′-fluorobiphenyl-4-yl)ethyl)-6-(thiophen-2-yl)-1,3-oxazinan-2-one (300 mg, 0.71 mmol) was added aqueous solution of KMnO 4 (66 mg, 0.42 mmol) and NaIO 4 (537 mg, 2.52 mmol). The reaction mixture was stirred at rt overnight. The reaction mixture was filtered and concentrated, then extracted with CH 2 Cl 2 . The organic phases was dried over Na 2 SO 4 , filtered and concentrated to afford 2-((S)-3-((S)-1-(4′-fluorobiphenyl-4-yl)ethyl)-2-oxo-6-(thiophen-2-yl)-1,3-oxazinan-6-yl)acetic acid (218 mg, 70%).
Step 3
A solution of 2-((S)-3-((S)-1-(4′-fluorobiphenyl-4-yl)ethyl)-2-oxo-6-(thiophen-2-yl)-1,3-oxazinan-6-yl)acetic acid (218 mg, 0.5 mmol) in THF anhydrous (10 mL) was added BH 3 (3.0 mL) at 0 and then stirred at reflux for 2 h. Then the reaction mixture quenched by water and separated, extracted with EtOAc twice. The organic phases was dried over Na 2 SO 4 , filtered and concentrated to afford the residue, which was purified by TLC to give (S)-3-((S)-1-(4′-fluorobiphenyl-4-yl)ethyl)-6-(2-hydroxyethyl)-6-(thiophen-2-yl)-1,3-oxazinan-2-one (85 mg, 40%). LC-MS Method 3 t R =1.35, min, m/z=426, 448; 1 H NMR (CD 3 OD): 1.50 (m, 3H), 2.15 (m, 2H), 2.30 (m, 1H), 2.40 (m, 1H), 2.60 (m, 1H), 3.15 (m, 1H), 3.45 (m, 1H), 3.70 (m, 1H), 5.60 (m, 1H), 6.90 (m, 1H), 7.00 (m, 1H), 7.10 (m, 4H), 7.35 (m, 3H), 7.55 (m, 2H).
(R)-3-((S)-1-(4′-fluorobiphenyl-4-yl)ethyl)-6-(2-hydroxyethyl)-6-(thiophen-2-yl)-1,3-oxazinan-2-one was prepared following a procedure analogous to that described immediately above. LC-MS Method 3 t R =1.4, min, m/z=426, 448; 1 H NMR (CD 3 OD) 1.38 (d, 3H), 2.01 (m, 1H), 2.18 (m, 3H), 2.41 (m, 1H), 2.86 (m, 1H), 3.02 (m, 1H), 3.41 (m, 1H), 3.72 (m, 1H), 5.62 (m, 1H), 6.98 (m, 1H), 7.03 (m, 1H), 7.15 (m, 1H), 7.36 (m, 3H), 7.58 (m, 4H).
Example 19
(R)-6-(3-hydroxypropyl)-3-((S)-1-(4-(6-oxo-1,6-dihydropyridin-3-yl)phenyl)ethyl)-6-phenyl-1,3-oxazinan-2-one
Step 1
A mixture of (R)-6-allyl-3-((S)-1-(4-bromophenyl)ethyl)-6-phenyl-1,3-oxazinan-2-one (150 mg, 0.375 mmol) and 6-aminopyridin-3-ylboronic acid (56 mg, 0.45 mmol), Pd(Ph 3 P) 2 Cl 2 (15 mg), and aqueous Cs 2 CO 3 solution (0.5 mL, 2 M) in 1,4-dioxane (10 mL) was stirred and heated to reflux for 2 h. The organic phase was separated, and concentrated to give the crude product, which was purified by preparative HPLC to give (R)-6-allyl-3-((S)-1-(4-(6-aminopyridin-3-yl)phenyl)ethyl)-6-phenyl-1,3-oxazinan-2-one (90 mg, 60%).
Step 2
To a solution of (R)-6-allyl-3-((S)-1-(4-(6-aminopyridin-3-yl)phenyl)ethyl)-6-phenyl-1,3-oxazinan-2-one (90 mg, 0.23 mmol) in tetrahydrofuran (10 mL) was added BH 3 THF (3.0 mL, 1 mol/L, 4 mmol) at 0° C. under nitrogen atmosphere. The formed mixture was stirred for 2 h. The reaction was quenched by water. Then NaOH (2 mL, 3 mol/L) and H 2 O 2 (1 mL) was added to the above mixture. When the reaction was over, the mixture was extracted with EtOAc. The combined organic phase was concentrated to give the crude product, which was purified by preparative HPLC to give (R)-3-((S)-1-(4-(6-aminopyridin-3-yl)phenyl)ethyl)-6-3-hydroxypropyl)-6-phenyl-1,3-oxazinan-2-one (40 mg, 41%).
Step 3
(R)-3-((S)-1-(4-(6-aminopyridin-3-yl)phenyl)ethyl)-6-(3-hydroxypropyl)-6-phenyl-1,3-oxazinan-2-one (40 mg, 0.09 mmoL) was dissolved in 3.5 M H 2 SO 4 (10 mL), and 2 M NaNO 2 (10 mL) was added at 0° C. The reaction mixture was stirred at rt for 2 h and treated with NaOH solution. The mixture was extracted with EtOAc. The combined organic layer was washed with brine, dried over anhydrous Na 2 SO 4 , and concentrated to afford the residue, which was purified by preparative HPLC to give (R)-6-(3-hydroxypropyl)-3-((S)-1-(4-(6-oxo-1,6-dihydropyridin-3-yl)phenyl)ethyl)-6-phenyl-1,3-oxazinan-2-one (10 mg, 20%). LC-MS Method 2 t R =1.66, min, m/z=433, 455; 1 H NMR (CDCl 3 ): 1.36 (m, 2H), 1.50 (m, 3H), 1.68 (m, 2H), 1.92 (m, 2H), 2.10-2.30 (m, 3H), 2.84 (m, 1H), 3.50 (m, 2H), 5.12 (m, 1H), 6.62 (m, 1H), 6.86 (m, 2H), 7.08 (m, 2H), 7.18-7.32 (m, 5H), 7.46 (m, 1H), 7.62 (m, 1H).
Example 20
(S)-3-((S)-1-(4′-fluorobiphenyl-4-yl)ethyl)-6-(2-hydroxy-2-methylpropyl)-6-phenyl-1,3-oxazinan-2-one
Step 1
A mixture of (R)-6-allyl-3-((S)-1-(4-bromophenyl)ethyl)-6-phenyl-1,3-oxazinan-2-one (5.83 g, 15 mmol), 4-fluorophenylboronic acid (3 g, 22 mmol), PdCl 2 (PPh 3 ) 2 (1 g, 1.4 mmol), and aqueous Cs 2 CO 3 solution (2 M, 8.0 mL) in 1,4-dioxane (50 mL) was heated to reflux for 2 h. The mixture was filtered, and the filtrate was extracted with EtOAc (3×). The combined organic layer was washed with brine, dried over Na 2 SO 4 and concentrated to give the crude product, which was purified by preparative TLC to give (R)-6-allyl-3-((S)-1-(4′-fluorobiphenyl-4-yl)ethyl)-6-phenyl-1,3-oxazinan-2-one (5.3 g, 88%).
Step 2
To a solution of (R)-6-allyl-3-((S)-1-(4′-fluorobiphenyl-4-yl)ethyl)-6-phenyl-1,3-oxazinan-2-one (3 g, 7.23 mmol) in acetone (20 mL) was added a solution of KMnO 4 (685 mg, 4.34 mmol) and NaIO 4 (5.6 g, 26 mmol) in H 2 O (15 mL) dropwise at 0° C. The mixture was stirred for 4 h. When TLC showed that the starting material had disappeared, the precipitate was removed by filtration, and the acetone was removed under reduced pressure. The resulting mixture was basified to pH=13 by the addition of 1 M aq NaOH, and then washed with ether (3×50 mL). The aqueous phase was acidified to pH=1 by addition of 1 N aq HCl, and extracted with CH 2 Cl 2 (3×15 mL). The organic layers were combined, washed with brine, dried over Na 2 SO 4 and concentrated in vacuo to give 2-((S)-3-((S)-1-(4′-fluorobiphenyl-4-yl)ethyl)-2-oxo-6-phenyl-1,3-oxazinan-6-yl) acetic acid (2.8 g, 90%).
Step 3
To a solution of 2-((S)-3-((S)-1-(4′-fluorobiphenyl-4-yl)ethyl)-2-oxo-6-phenyl-1,3-oxazinan-6-yl) acetic acid (1 g, 2.3 mmol) in MeOH (15 mL) was added thionyl chloride (408 mg, 3.5 mmol) dropwise at 0° C. under N 2 atmosphere. After refluxing overnight, the mixture was concentrated to give the crude product, which was purified by chromatography to give methyl 2-((S)-3-((S)-1-(4′-fluorobiphenyl-4-yl)ethyl)-2-oxo-6-phenyl-1,3-oxazinan-6-yl) acetate (680 mg, 68%).
Step 4
To a solution of methyl 2-((S)-3-((S)-1-(4′-fluorobiphenyl-4-yl)ethyl)-2-oxo-6-phenyl-1,3-oxazinan-6-yl)acetate (180 mg, 0.4 mmol) in dry THF (5 mL) under N 2 at −78° C. was added methylmagnesium bromide (1.5 mL, 3 M, 4.5 mmol) dropwise at −78° C. After addition, the mixture was stirred for 1 h at rt. Then the reaction was quenched with water and the mixture was extracted with ethyl acetate for three times (3×5 mL). The organic layers were combined, washed with brine, dried over Na 2 SO 4 , filtered and concentrated. The residue was purified by preparative HPLC to give (S)-3-((S)-1-(4′-fluorobiphenyl-4-yl)ethyl)-6-(2-hydroxy-2-methylpropyl)-6-phenyl-1,3-oxazinan-2-one (2.48 mg, 1%). 1 H NMR (CDCl 3 ): 1.05 (s, 1H), 1.13 (s, 3H), 1.50 (d, 3H), 2.14-2.23 (m, 2H), 2.25-2.40 (m, 1H), 2.80 (m, 1H), 5.63 (m, 1H), 6.94 (m, 2H), 7.02 (m, 2H), 7.18-7.30 (m, 7H), 7.38 (m, 2H). LC-MS Method 3 t R =1.51, min, m/z=448, 470.
Example 21
5-(4-((S)-1-((R)-6-(4-fluorophenyl)-6-(3-hydroxypropyl)-2-oxo-1,3-oxazinan-3-yl)ethyl)phenyl)nicotinamide
Step 1
To a solution of (R)-6-allyl-3-((S)-1-(4-bromophenyl)ethyl)-6-(4-fluorophenyl)-1,3-oxazinan-2-one (1 g, 2.4 mmol) in dry THF (15 mL) was added dropwise BH 3 .THF (5 mL, 1 M) at 0° C. After stirring for 2 h at rt, the reaction mixture was cooled to 0° C. and water (1 mL), aqueous NaOH (0.5 mL, 3 M) and H 2 O 2 (0.5 mL, 30%) were successively added. The mixture was stirred for 2-3 h at rt and diluted with water (8 mL). The pH was adjusted to 6-7 with 0.5 N HCl. The layers were separated, and the aqueous phase was extracted with EtOAc (3×10 mL). The combined organic layers were washed with a satd aq NaHCO 3 (20 mL) and brine (20 mL), dried over Na 2 SO 4 , and concentrated in vacuo to give the crude product, which was purified by preparative TLC to afford (R)-3-((S)-1-(4-bromophenyl)ethyl)-6-(4-fluorophenyl)-6-(3-hydroxypropyl)-1,3-oxazinan-2-one (400 mg, 38%).
Step 2
A mixture of (R)-3-((S)-1-(4-bromophenyl)ethyl)-6-(4-fluorophenyl)-6-(3-hydroxypropyl)-1,3-oxazinan-2-one (250 mg, 0.6 mmol), 5-(methoxycarbonyl)pyridin-3-ylboronic acid (163 mg, 0.9 mmol), PdCl 2 (PPh 3 ) 2 (50 mg, 20%) and aqueous Cs 2 CO 3 solution (2 M, 2 mL) in 1,4-dioxane (6 mL) was heated to reflux at 100° C. overnight under N 2 . The mixture was filtered, and the filtrate was extracted with EtOAc for 3 times. The combined organic layer was washed with brine, dried over Na 2 SO 4 and concentrated to the crude product, which was purified by preparative HPLC to give methyl 5-(4-((S)-1-((R)-6-(4-fluorophenyl)-6-(3-hydroxypropyl)-2-oxo-1,3-oxazinan-3-yl)ethyl)phenyl)nicotinate (220 mg, crude).
Step 3
Methyl 5-(4-((S)-1-((R)-6-(4-fluorophenyl)-6-(3-hydroxypropyl)-2-oxo-1,3-oxazinan-3-yl)ethyl)phenyl)nicotinate (30 mg, 0.1 mmol) was dissolved in anhydrous NH 3 in EtOH (5 mL). Then the mixture was stirred at rt overnight. The solvent was removed in vacuo to give the crude product, which was purified by preparative HPLC to provide 5-(4-((S)-1-((R)-6-(4-fluorophenyl)-6-(3-hydroxypropyl)-2-oxo-1,3-oxazinan-3-yl)ethyl)phenyl) nicotinamide (10 mg, 34%). LC-MS Method 2 t R =1.022 min, m/z=478; 1 H NMR (CD 3 OD): 1.31 (m, 1H), 1.56 (m, 3H), 1.59 (m, 1H), 1.91 (m, 2H), 2.17-2.28 (m, 1H), 2.33 (m, 1H), 2.44 (m, 1H), 3.14 (m, 1H), 3.44 (m, 2H), 5.60 (m, 1H), 7.04-7.17 (m, 4H), 7.29 (m, 2H), 7.49 (m, 2H), 8.41 (m, 1H), 8.86 (m, 1H), 8.97 (m, 1H).
Example 22
(S)-3-((S)-1-(4-bromophenyl) ethyl)-6-(2-hydroxy-2-methylpropyl)-6-phenyl-1,3-oxazinan-2-one
Step 1: (S)-1-bromo-4-(1-isocyanatoethyl)benzene
To a solution of (S)-1-(4-bromophenyl)ethanamine (240 g, 1.2 mol) in methylene chloride (3 L) and satd aq NaHCO 3 (3 L) solution was added triphosgene (118 g, 0.396 mol) at 0° C. The mixture was stirred for 15 min. The organic phase was separated, dried over Na 2 SO 4 and concentrated to give 1-bromo-4-(1-isocyanato-ethyl)-benzene (170 g, 63%).
Step 2: 1-chloro-3-phenylhex-5-en-3-ol
To a solution of 3-chloro-1-phenylpropan-1-one (170 g, 1.01 mol) in anhydrous THF (1200 mL) was added allylmagnesium bromide (1.2 L, 1 mol/L) at −78° C. under nitrogen. The formed mixture was stirred for 30 min at −78° C. The reaction was quenched with aqueous NaHCO 3 solution. The organic phase was separated, dried over Na 2 SO 4 and concentrated to give the crude product, which was purified by column chromatography (petroleum ether/EtOAc=100:1) to afford 1-chloro-3-phenylhex-5-en-3-ol (180 g, 86%). 1 H NMR (CDCl 3 ): 2.27 (m, 2H), 2.51 (m, 1H), 2.74 (m, 1H), 3.22 (m, 1H), 3.58 (m, 1H), 5.16 (m, 2H), 5.53 (m, 1H), 7.23 (m, 1H), 7.39 (m, 4H).
Step 3: (R)-6-allyl-3-((S)-1-(4-bromophenyl)ethyl)-6-phenyl-1,3-oxazinan-2-one
A mixture of 1-chloro-3-phenyl-hex-5-en-3-ol (105 g, 0.050 mmol), (S)-(−)-1-(-bromophenyl)ethyl isocyanate (170 g, 0.752 mol), and DBU (228 g, 1.5 mol) in THF (1700 mL) was heated to reflux overnight. The mixture was diluted with EtOAc and washed with 1N aq HCl. The aqueous phase was extracted with EtOAc (3×). The combined organic phase was dried over Na 2 SO 4 . After the solvents were evaporated, the crude product was purified by column chromatography (petroleum ether/EtOAc=20:1 to 5:1) to give (R)-6-allyl-3-((S)-1-(4-bromophenyl)ethyl)-6-phenyl-1,3-oxazinan-2-one (100 g, 34%). 1 H NMR (CDCl 3 ): 1.39 (d, 3H), 2.14 (m, 1H), 2.24 (m, 2H), 2.48-2.61 (m, 3H), 2.82 (m, 2H), 5.01 (m, 2H), 5.52 (q, 1H), 5.73 (m, 1H), 6.62 (d, 2H), 7.12 (m, 2H), 7.28 (m, 2H).
Step 4: (S)-3-((S)-1-(4-bromophenyl)ethyl)-6-(2-oxopropyl)-6-phenyl-1,3-oxazinan-2-one and 3-((R)-3-((S)-1-(4-bromophenyl)ethyl)-2-oxo-6-phenyl-1,3-oxazinan-6-yl)propanal
To a solution of (R)-6-allyl-3-((S)-1-(4-bromophenyl)ethyl)-6-phenyl-1,3-oxazinan-2-one (31 g, 78 mmol) and CuCl (19.3 g, 195 mmol) in dry DMF (150 mL) was added H 2 O (50 mL) and PdCl 2 (4.10 g, 23 mmol) at rt. After addition, the mixture was stirred overnight under oxygen. After TLC showed the starting material had disappeared, the solid was filtered off. Water (200 mL) and EtOAc (200 mL) was added, the organic layers were separated and the aqueous layer was extracted with EtOAc (3×40 mL). The combined organic layer was washed with brine, dried over Na 2 SO 4 , filtered and concentrated to give a residue which was purified by column chromatography (petroleum ether/EtOAc=5:1 to 1:1) to give a mixture of (S)-3-((S)-1-(4-bromophenyl)ethyl)-6-(2-oxopropyl)-6-phenyl-1,3-oxazinan-2-one and 3-((R)-3-((S)-1-(4-bromophenyl)ethyl)-2-oxo-6-phenyl-1,3-oxazinan-6-yl)propanal, (26 g, 81%).
Step 5: (S)-3-((S)-1-(4-bromophenyl)ethyl)-6-(2-oxopropyl)-6-phenyl-1,3-oxazinan-2-one
To a mixture of (S)-3-((S)-1-(4-bromophenyl)ethyl)-6-(2-oxopropyl)-6-phenyl-1,3-oxazinan-2-one and 3-((R)-3-((S)-1-(4-bromophenyl)ethyl)-2-oxo-6-phenyl-1,3-oxazinan-6-yl)propanal (20 g, 48.2 mmol) in t-BuOH (250 mL) and 2-methyl-2-butene (50 mL) was added a solution of NaClO 2 (19.3 g, 0.213 mol) and NaH 2 PO 4 (28 g, 0.179 mol) in H 2 O (300 mL) at 0° C. The formed mixture was stirred for 1 h at 0° C. The mixture was treated with water (100 mL) and extracted with CH 2 Cl 2 . The combined organic layer was dried over Na 2 SO 4 , filtered and concentrated to leave a residue, which was purified by column chromatography (petroleum ether/EtOAc=5:1 to 2.5:1) to afford (S)-3-((S)-1-(4-bromophenyl)ethyl)-6-(2-oxopropyl)-6-phenyl-1,3-oxazinan-2-one (10.0 g, 83%). 1 H NMR (CDCl 3 ): 1.49 (d, 3H), 2.12 (s, 3H), 2.33 (m, 2H), 2.63 (m, 1H), 2.86-3.08 (m, 3H), 5.57 (q, 1H), 6.66 (d, 2H), 7.19 (m, 2H), 7.33 (m, 5H).
Step 6: (S)-3-((S)-1-(4-bromophenyl) ethyl)-6-(2-hydroxy-2-methylpropyl)-6-phenyl-1,3-oxazinan-2-one
To a solution of (S)-3-((S)-1-(4-bromophenyl)ethyl)-6-(2-oxopropyl)-6-phenyl-1,3-oxazinan-2-one (20 g, 46.4 mmol) in anhydrous THF (200 mL) was added dropwise methylmagnesium bromide (31 mL, 144 mmol) at −78° C. under nitrogen. Then the mixture was stirred at rt for 1 h. The reaction mixture was quenched with aq NaHCO 3 (50 mL) under ice water bath. The organic layers were separated. The aqueous layer was extracted with EtOAc (150 mL). The combined organic layers were washed with brine, dried over Na 2 SO 4 and concentrated in vacuo to give the crude product, which was purified column chromatography (petroleum ether/EtOAc=5:1 to 2:1) to afford (S)-3-((S)-1-(4-bromophenyl)ethyl)-6-(2-hydroxy-2-methylpropyl)-6-phenyl-1,3-oxazinan-2-one (13 g, 65%). After re-crystallization from EtOH, 4 g of the pure compound was obtained. 1 H NMR (CDCl 3 ): 1.06 (s, 3H), 1.12 (s, 3H), 1.44 (d, 3H), 2.14 (m, 3H), 2.21 (m, 1H), 2.33 (m, 1H), 2.76 (m, 1H), 5.54 (q, 1H), 6.74 (d, 2H), 7.16 (d, 2H), 7.28 (m, 5H).
Example 23
Reverse Suzuki
6-(4-{1-[6-(2-Hydroxy-2-methyl-propyl)-2-oxo-6-phenyl-[1,3]oxazinan-3-yl]-ethyl}-phenyl)-N-methyl-nicotinamide
Step 1
To a solution of (S)-3-((S)-1-(4-bromophenyl)ethyl)-6-(2-hydroxy-2-methylpropyl)-6-phenyl-1,3-oxazinan-2-one (6.6 g, 15.2 mmol) and 4,4,4′,4′,5,5,5′,5′-octamethyl-2,2′-bi(1,3,2-dioxaborolane) (6.1 g, 24.3 mmol) in dry DMSO (20 mL) was added KOAc (4.8 g, 48.6 mmol) and Pd(dppf)Cl 2 (372 mg, 0.46 mmol). After addition, the mixture was warmed to 100° C. for 20 h. After TLC showed the starting material had disappeared, the solid was filtered off Water (60 mL) and EtOAc (20 mL) were added, the layers were separated and the aqueous layer was extracted with EtOAc (3×15 mL). The combined organic layer was washed with brine, dried over Na 2 SO 4 , filtered and concentrated to give (S)-6-(2-hydroxy-2-methylpropyl)-6-phenyl-3-((S)-1-(4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl)ethyl)-1,3-oxazinan-2-one (4.4 g, 60%), which was purified by column. 1 H NMR (CDCl 3 ): 1.03 (s, 3H), 1.12 (s, 3H), 1.22 (s, 12H), 1.49 (d, 3H), 2.13 (m, 4H), 2.26 (m, 1H), 2.73 (m, 1H), 5.64 (q, 1H), 6.91 (d, 2H), 7.38 (m, 5H), 7.51 (d, 2H).
Step 2
To a solution of (S)-6-(2-hydroxy-2-methylpropyl)-6-phenyl-3-((S)-1-(4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl)ethyl)-1,3-oxazinan-2-one (500 mg, 1.04 mmol) and methyl 6-bromonicotinate (292 mg, 1.35 mmol) in dry 1,4-dioxane (5 mL) was added CsCO 3 (1 mL, 2 mmol) and Pd(PPh 3 ) 2 Cl 2 (50 mg). After addition, the mixture was warmed to 110° C. for 30 min under microwave. After TLC showed the starting material had disappeared, the solid was filtered off Water (20 mL) and EtOAc (10 mL) was added, the layers were separated and the aqueous layer was extracted with EtOAc (3×10 mL). The combined organic layer was washed with brine, dried over Na 2 SO 4 , filtered and concentrated to give methyl 6-(4-((S)-1-((S)-6-(2-hydroxy-2-methylpropyl)-2-oxo-6-phenyl-1,3-oxazinan-3-yl)ethyl)phenyl)nicotinate (507 mg, 89%), which was purified by preparative TLC. 1 H NMR (CDCl 3 ): 1.13 (s, 3H), 1.19 (s, 3H), 1.61 (d, 3H), 2.24 (m, 4H), 2.37 (m, 1H), 2.88 (m, 1H), 4.02 (s, 3H), 5.76 (q, 1H), 7.11 (d, 2H), 7.29-7.47 (m, 6H), 7.78 (m, 1H), 7.82 (m, 2H), 8.38 (d, 1H), 9.31 (s, 1H).
Step 3
Methyl 6-(4-((S)-1-((S)-6-(2-hydroxy-2-methylpropyl)-2-oxo-6-phenyl-1,3-oxazinan-3-yl)ethyl)phenyl)nicotinate (150 mg, 0.307 mmol) was dissolved in NH 2 Me/MeOH (10 mL). The mixture was stirred at rt overnight. The solvent was removed in vacuo to give the crude product, which was purified by preparative HPLC and chiral HPLC to afford 6-(4-((S)-1-((S)-6-(2-hydroxy-2-methylpropyl)-2-oxo-6-phenyl-1,3-oxazinan-3-yl) ethyl)phenyl)-N-methylnicotinamide (54 mg, 36%). LC-MS Method 2 t R =1.117 min, m/z=430.1; 1 H NMR (CD 3 OD) 0.93 (s, 3H), 1.27 (s, 3H), 1.59 (d, 3H), 2.16 (s, 2H), 2.22-2.37 (m, 1H), 2.41-2.60 (m, 2H), 2.99 (s, 3H), 3.11 (m, 1H), 5.60 (m, 1H), 7.12 (d, 1H), 7.29 (m, 5H), 7.80 (m, 2H), 8.01 (d, 1H), 8.41 (d, 1H), 9.03 (s, 1H).
The teachings of all patents, published applications and references cited herein are incorporated by reference in their entirety.
While this invention has been particularly shown and described with references to example embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the scope of the invention encompassed by the appended claims. | Disclosed are syntheses of 11β-HSD1 inhibitors and corresponding intermediates that are promising for the treatment of a variety of disease states including diabetes, metabolic syndrome, obesity, glucose intolerance, insulin resistance, hyperglycemia, hypertension, hypertension-related cardiovascular disorders, hyperlipidemia, deleterious gluco-corticoid effects on neuronal function (e.g. cognitive impairment, dementia, and/or depression), elevated intra-ocular pressure, various forms of bone disease (e.g., osteoporosis), tuberculosis, leprosy (Hansen's disease), psoriasis, and impaired wound healing (e.g., in patients that exhibit impaired glucose tolerance and/or type 2 diabetes). | 2 |
BACKGROUND
[0001] 1. Field of the Invention
[0002] The invention relates to the process of fabricating integrated circuits. More specifically, the invention relates to a method and an apparatus for fracturing polygons on masks used in an optical lithography process for fabricating integrated circuits.
[0003] 2. Related Art
[0004] Recent advances in integrated circuit technology have largely been accomplished by decreasing the feature size of circuit elements on a semiconductor chip. As the feature size of these circuit elements continues to decrease, circuit designers are forced to deal with problems that arise as a consequence of the optical lithography process that is typically used to manufacture integrated circuits. This optical lithography process begins with the formation of a photoresist layer on the surface of a semiconductor wafer. A mask composed of opaque regions, which are generally formed of chrome, and light-transmissive clear regions, which are generally formed of quartz, is then positioned over this photoresist layer. (Note that the term “mask” as used in this specification is meant to include the term “reticle.”) Light is then shone on the mask from a visible light source, an ultraviolet light source, or more generally some type of electromagnetic radiation source together with suitably adapted masks and lithography equipment.
[0005] This image is reduced and focused through an optical system containing a number of lenses, filters, and mirrors. The light passes through the clear regions of the mask and exposes the underlying photoresist layer. At the same time, opaque regions of the mask block the light leaving underlying portions of the photoresist layer unexposed.
[0006] The exposed photoresist layer is then developed, through chemical removal of either the exposed or non-exposed regions of the photoresist layer. The end result is a semiconductor wafer with a photoresist layer having a desired pattern. This pattern can then be used for etching underlying regions of the wafer.
[0007] The masks used to expose the photoresist layer are typically processed by an optical proximity correction (OPC) process to alleviate problems cause by the diffraction of the exposure radiation at the feature edges, and over-etching of the photoresist at the ends of the features. The OPC process adds elements such as serifs and hammerheads to the original polygons. These added elements (and some of the original polygons) can cause problems during the mask writing process because the mask writing equipment can typically print only rectangles and trapezoids. Hence, after the OPC process, mask features are typically “fractured” so that each exposure element is a rectangle or a trapezoid.
[0008] For example, FIG. 1A illustrates a polygon 102 with serifs 103 that have been added by the OPC process. Since polygon 102 is not a rectangle or a trapezoid, a fracturing process is performed on polygon 102 to slice polygon 102 into rectangles and trapezoids. This fracturing process occurs because of limitations within the mask writing equipment.
[0009] [0009]FIG. 1B illustrates a cut that is made during the process of fracturing a polygon into rectangles and trapezoids. During the fracturing process, a cut 104 from a vertex 105 is considered in an attempt to eliminate the cavity 107 in polygon 102 . However, this cut is rejected because it creates a “sliver” 106 , which is too small to be printed easily.
[0010] In an attempt to fracture the polygon into rectangles without creating slivers, designers developed a fracturing process that determines the smaller width of the two resulting shapes on each side of the slice. The system considers at all possible slices from a vertex in this way and selects the slice that produces the greatest smaller width. For example, FIG. 1C illustrates a slice 108 that is made using this technique. Note that the slice 108 is made instead of the sliver 106 in FIG. 1B because the width of resulting shape 109 is larger than the width of sliver 106 made by cut 104 illustrated in FIG. 1. This slicing technique eliminates the slivers. However, slicing the polygon 102 lengthwise in this way fractures critical dimension 112 into multiple rectangles, which can create registration problems during the multiple exposures required to expose the mask blank. This gives rise to unwanted variations in the critical dimension 112 . Additionally, since some of the rectangles are relatively long, multiple exposures (shots) may be required to expose these rectangles.
[0011] A sliver is a rectangle or a trapezoid whose minimum width is below a user-defined threshold. The polygon-fracturing algorithm targets “shaped beam” electron photolithography, where the mask is exposed by photographic equipment, which directs the beam through a keyhole aperture. If this aperture is too narrow, the exposure will be less successful than normal. Machine parameters dictate what this minimum aperture width; any shape which falls below this minimum aperture width is termed a “sliver.”
[0012] Hence, what is needed is a method and an apparatus for fracturing polygons used in an optical lithography process without the problems described above.
SUMMARY
[0013] One embodiment of the invention provides a system for fracturing polygons on masks used in an optical lithography process for manufacturing an integrated circuit. The system operates by first receiving a mask layout to be used in fabricating the integrated circuit, wherein the mask layout includes a polygon that defines a desired feature on the integrated circuit, and wherein the polygon is either x-convex or y-convex, but not both x-convex and y-convex. Convexity is defined below in conjunction with FIG. 2. For a given vertex on the polygon, the system calculates an aspect ratio for each possible slice that extends from the vertex, wherein the aspect ratio for a slice is the slice length divided by the smaller of the two resulting widths on each side of the slice. The system then selects the slice with the smallest aspect ratio. Next, the system applies the slice with the smallest aspect ratio to the polygon. In this way the system avoids slices that create extreme aspect ratios.
[0014] In a variation of this embodiment, the system receives the mask layout after an OPC process has been applied to the mask layout.
[0015] In a variation of this embodiment, the system repeats the steps of calculating the aspect ratio, selecting the smallest aspect ratio, and applying the slice until each remaining polygon is a rectangle or a trapezoid.
[0016] In a further variation, the system first considers slices that originate from cavity corner vertices.
[0017] In a further variation, if the vertex is within a cavity between two serifs on corners of a line end, the system also considers a “roof cut” slice that separates the serifs and part of the line end from the rest of the line.
[0018] In a further variation, if a slice width is less that a pre-specified minimum width, the system reports a violation.
[0019] In a further variation, a critical dimension of the desired feature is not sliced.
BRIEF DESCRIPTION OF THE FIGURES
[0020] [0020]FIG. 1A illustrates a polygon with serifs.
[0021] [0021]FIG. 1B illustrates a slice applied to the polygon illustrated in FIG. 1A.
[0022] [0022]FIG. 1C illustrates another possible slice applied to the polygon illustrated in FIG. 1A.
[0023] [0023]FIG. 2 illustrates an exemplary y-convex polygon in accordance with an embodiment of the invention.
[0024] [0024]FIG. 3A illustrates measurements obtained to compute the aspect ratio for a normal cut in accordance with an embodiment of the invention.
[0025] [0025]FIG. 3B illustrates measurements obtained to compute the aspect ratio for a substitute cut in accordance with an embodiment of the invention.
[0026] [0026]FIG. 3C illustrates measurements obtained to compute the aspect ratio for a roof cut in accordance with an embodiment of the invention.
[0027] [0027]FIG. 4A illustrates the process of considering a normal cut in the upper sub-polygon after the roof cut has been applied in accordance with an embodiment of the invention.
[0028] [0028]FIG. 4B illustrates additional cuts in accordance with an embodiment of the invention.
[0029] [0029]FIG. 5 presents a flowchart illustrating the process of slicing a polygon in accordance with an embodiment of the invention.
[0030] [0030]FIG. 6A illustrates an exemplary fracturing of a layout using existing techniques.
[0031] [0031]FIG. 6B illustrates an exemplary fracturing of the same layout as in FIG. 6A using a technique that considers the aspect ratios generated by each slice in accordance with an embodiment of the present invention.
DEFINITIONS
[0032] Sliver: a rectangle or a trapezoid whose minimum width is below a user-defined threshold.
DETAILED DESCRIPTION
[0033] Introduction
[0034] The mask data preparation, or colloquially fracturing, process occurs at the end of the electronic design automation (EDA) process to “tape out” the mask data for mask writing machines. Improvements to the fracturing technique can result in enhanced masks and ultimately improved semiconductors and chips. The invention will be described as follows. A mask layout is examined to locate polygons that are exclusively x-convex or y-convex. The aspect ratio is then calculated for each possible slice at a vertex of the polygon, and the slice with the lowest aspect ratio is selected. Selecting the slice with the lowest aspect ratio produces sub-polygons that are “short” and “fat.” This process avoids slices with extreme aspect ratios (i.e., “long,” “skinny” slices). After this slice has been applied, the process is repeated for the next vertex until each sub-polygon is either a rectangle or a trapezoid.
[0035] Convex Polygons
[0036] One embodiment of the present invention seeks to apply cuts to polygons that are either x-convex or y-convex, but not both. Note that other polygons that are both x-convex and y-convex, or are neither x-convex nor y-convex can be fractured using other techniques.
[0037] [0037]FIG. 2 illustrates an exemplary y-convex polygon in accordance with an embodiment of the invention. Polygon 202 is y-convex because any possible vertical line 214 enters and exits polygon 202 only once. Line 214 enters polygon 202 at point 216 and exits polygon 202 at point 218 . Moving line 214 left or right from the position shown in FIG. 2 to any other point passing through polygon 202 will still yield a single entry point and a single exit point for line 214 . Since polygon 202 meets this condition, it is y-convex.
[0038] Polygon 202 , however, is not x-convex because line 204 enters and exits polygon 202 twice in some positions. As shown in FIG. 2, line 204 enters polygon 202 at point 206 , exits at point 208 , enters at point 210 , and exits at point 212 . However, the polygon 202 rotated 90° once either left or right would be an x-convex polygon.
[0039] Calculating Aspect Ratio
[0040] [0040]FIG. 3A illustrates measurements obtained to compute the aspect ratio for a perpendicular cut 304 in accordance with an embodiment of the invention. The system starts by considering a vertex 302 . Note that in one embodiment of the present invention, the system considers vertices associated with cavity corners, such as vertex 302 prior to considering other vertices. Two possible cuts originate from vertex 302 —a “normal cut” and a “substitute cut.” Perpendicular cut 304 creates slice 306 and the system calculates the aspect ratio for slice 306 by dividing the length of slice 306 by the smaller of the two resulting widths on either side of the slice. The smaller of the two resulting widths is chosen because the smaller width is closer to the sliver width. The smaller width, therefore, will eventually result in the generation of the smaller rectangle or trapezoid whose width is of concern if it is below the sliver width.
[0041] [0041]FIG. 3B illustrates measurements obtained to compute the aspect ratio for a substitute cut in accordance with an embodiment of the invention. Parallel cut 308 creates slice 310 . Before making this cut, the system calculates the aspect ratio for slice 310 by dividing the length of slice 310 by the smaller width on either side of slice 310 .
[0042] [0042]FIG. 3C illustrates measurements obtained to compute the aspect ratio for a roof cut in accordance with an embodiment of the invention. In order to make roof cut 314 , the system locates vertex 312 on the same side of the polygon as vertex 302 . Roof cut 314 is then made on polygon 102 creating slice 316 . The system then calculates the aspect ratio for slice 316 . After examining the aspect ratios for slices 306 , 310 , and 316 , the system chooses the slice with the lowest aspect ratio to apply to polygon 102 . This can also be viewed as selecting the cut that results in the slice with the lowest aspect ratio. For the polygon 102 illustrated in FIGS. 3 A-C, the chosen slice is slice 316 created by the roof cut 314 .
[0043] Final Cuts
[0044] [0044]FIG. 4A illustrates the process of considering a normal cut in the upper sub-polygon after the roof cut has been applied in accordance with an embodiment of the invention. Specifically, the cavity of the original polygon 102 remains in the slice 316 and the slice must still be decomposed into rectangles and trapezoids. Therefore, the system has to work through the vertices of the slice 316 and select cuts using an aspect-ratio dependent decision making process analogous to the one described in connection with FIGS. 3 A-C. Here, cut 402 from vertex 302 creating slice 404 is selected to help eliminate the cavity and convert the slice to rectangles and trapezoids. This selection is made after comparing the aspect ratio of slice 404 with the recomputed aspect ratio for the slice 310 in the context of slice 316 .
[0045] [0045]FIG. 4B illustrates additional cuts in accordance with an embodiment of the invention. The system continues with cuts from the cavity vertices until the cavity is eliminated. Cut 408 is applied from the other vertex of the cavity creating slices 410 and 414 . Since all of the slices of polygon 102 are now either rectangles or trapezoids, the process is complete. Note that this process eliminates the long “normal” slices along the critical dimension of polygon 102 .
[0046] Slicing a Polygon
[0047] [0047]FIG. 5 presents a flowchart illustrating the process of slicing a polygon in accordance with an embodiment of the invention. The system starts when a mask layout is received after an optional optical proximity correction (OPC) operation has been applied to the mask layout (step 502 ). In some embodiments the layout is received in a GDS-II format. In other embodiments, the layout is stored in a Milkyway database format and step 502 includes accessing the database during the process of FIG. 5. Still other formats can be used for the layout data, e.g. OpenAccess, etc. Next, the system determines if all layout geometry has been sliced (step 504 ). If so, the process is terminated.
[0048] If all layout geometry has not been sliced, the system selects a polygon from within the layout (step 508 ). Next, the system determines if the polygon is neither x-convex nor y-convex (step 508 ). If so, the system continues to slice the polygon until al sub-polygons are x-convex, y-convex, or both (step 510 ). The process then returns to step 504 to determine if all layout geometry has been sliced.
[0049] If the polygon is neither x-convex nor y-convex at step 508 , the system determines if the polygon is both x-convex and y-convex (step 512 ). If so, the system finishes slicing the polygon into rectangles and trapezoids (step 514 ). The process then returns to step 504 to determine if all layout geometry has been sliced.
[0050] If the polygon is not both x-convex and y-convex at step 512 , the polygon is either x-convex or y-convex. In this case, the system then determines if all cavity vertices have been visited (step 516 ). If not, the system calculates the aspect ratios of the three prospective cut options—the normal cut, the substitute cut, and the roof cut—at a vertex remembering the “best cut option” for this vertex (Step 518 ). Next, the system determines if this cavity vertex's aspect is the best so far (step 520 ). If not, the process returns to step 516 to determine if all cavity vertices have been visited.
[0051] If this cavity vertex's aspect is the best so far at step 520 , the system remembers the “best cavity vertex” and its “best cut option” (step 522 ). The process then returns to step 516 to determine if all cavity vertices have been visited. When all cavity vertices have been visited at step 516 , the system applies the “best cut option” for the “best cavity vertex” (step 524 ). The process then returns to step 504 to determine if all layout geometry has been sliced.
EXAMPLE
[0052] [0052]FIG. 6A illustrates an exemplary fracturing of a layout using an existing technique. In contrast, FIG. 6B illustrates an exemplary fracturing of the same layout using a technique that considers the aspect ratios generated by each slice in accordance with an embodiment of the present invention and makes use of roof cuts. Note that the existing technique fractures some of the wires lengthwise, which can cause critical dimension problems, whereas the new technique does not because it considers aspect ratios. Note also that this technique can be applied to any polygon that is x-convex or y-convex, but not to polygons that are both or neither x-convex and y-convex.
CONCLUSION
[0053] The foregoing description is presented to enable one to make and use the invention, and is provided in the context of a particular application and its requirements. It is not intended to be exhaustive or to limit the invention to the forms disclosed. Various modifications to the disclosed embodiments will be readily apparent, and the general principles defined herein may be applied to other embodiments and applications without departing from the spirit and scope of the invention. Thus, the invention is not intended to be limited to the embodiments shown, but is to be accorded the widest scope consistent with the principles and features disclosed herein. Accordingly, many modifications and variations will be apparent. The scope of the invention is defined by the appended claims.
[0054] The data structures and code described in this detailed description can be stored on a computer readable storage medium, which may be any device or medium that can store code and/or data for use by a computer system. This includes, but is not limited to, magnetic and optical storage devices such as disk drives, magnetic tape, CDs (compact discs) and DVDs (digital versatile discs or digital video discs), and computer instruction signals embodied in a transmission medium (with or without a carrier wave upon which the signals are modulated). For example, the transmission medium may include a communications network, such as the Internet. For example, embodiments of the invention can include mask data preparation software that implements the processes of FIG. 5 accessed across a network. In some embodiments, the invention can be implemented as an alternate to existing fracturing algorithms in mask data preparation software. For example, the CATS™ software from Synopsys, Inc., Mountain View, Calif., could be support the processes described.
[0055] Note that the invention can be applied to any type of lithographic process for fabricating semiconductor chips, including processes that make use of, deep-ultraviolet (DUV) radiation, extreme ultraviolet (EUV) radiation, X-rays, and electron beams, along with suitably modified masks. | A system for fracturing polygons on masks used in lithography processes for manufacturing an integrated circuit is described. The system fractures polygons that include cavities in either the horizontal edges or the vertical edges by examining the aspect ratio (length/width) of prospective slices made at each vertex of the polygon. After determining the aspect ratio of each prospective slice, the system selects the slice with the lowest aspect ratio and slices the polygon into two sub-polygons. Slicing the polygon in this manner effectively eliminates “slivers” or slices with extreme aspect ratios. This process is continued until each sub-polygon is either a rectangle or a trapezoid that can be printed by electron beam photolithography. | 6 |
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a process and apparatus for sludge lancing nuclear steam generators to remove sludge deposits from the upper surface of the tube sheet. More particularly, the present invention provides a sludge lance system wherein at no time is the pressure blasts of the high pressure water jets obstructed by any component of the sludge lance system.
BACKGROUND OF THE INVENTION
A typical nuclear steam generator comprises a vertically-oriented shell, a plurality of U-shaped tubes disposed in the shell so as to form a tube bundle, a tubesheet for supporting the tubes at the ends opposite the U-shaped curvature, a dividing plate that cooperates with the tubesheet forming a primary fluid inlet plenum at the one end of the tube bundle and a primary fluid outlet plenum at the other end of the tube bundle, a primary fluid inlet nozzle in fluid communication with the primary fluid inlet plenum, and a primary fluid outlet nozzle in fluid communication with the primary fluid outlet plenum. The steam generator also comprises a wrapper disposed between the tube bundle and the shell to form an annular chamber adjacent the shell and a feedwater ring disposed above the U-shaped curvature end of the tube bundle. The primary fluid having been heated by circulation through the reactor core enters the steam generator through the primary fluid inlet nozzle. From the primary fluid inlet nozzle, the primary fluid is conducted through the primary fluid inlet plenum, through the U-tube bundle, out the primary fluid outlet plenum, through the primary fluid outlet nozzle to the remainder of the reactor coolant system. At the same time, feedwater is introduced to the steam generator through the feedwater ring. The feedwater is conducted down the annular chamber adjacent the shell until the tubesheet near the bottom of the annular chamber causes the feedwater to reverse direction passing in heat transfer relationship with the outside of the U-tubes and up through the inside of the wrapper. While the feedwater is circulating in heat transfer relationship with the tube bundle, heat is transferred from the primary fluid in the tubes to the feedwater surrounding the tubes causing a portion of the feedwater to be converted to steam. The steam then rises and is circulated through typical electrical generating equipment thereby generating electricity in a manner well known in the art.
Since the primary fluid contains radioactive particles and is isolated from the feedwater only by the U-tube walls which may be constructed by Inconel®, the U-tube walls form part of the primary boundary for isolating these radioactive particles. It is, therefore, important that the U-tubes be maintained defect-free so that no breaks will occur in the U-tubes. However, experience has shown that under certain circumstances, the U-tubes may develop leaks therein which allow radioactive particles to contaminate the feedwater, which is a highly undesirable and dangerous result.
There is now thought to be at least two causes of tube leaks in steam generators. One cause of these leaks is considered to be related to the chemical environment of the feedwater side of the tubes. Analysis of the tube samples taken from operating steam generators which have experienced leaks has shown that the leaks were caused by cracks in the tubes resulting from intergranular corrosion. High caustic levels found in the vicinity of the cracks in the tube specimens taken from operating steam generators and the similarity of these cracks to failures produced by caustic under controlled laboratory conditions have identified high caustic levels as the cause of the intergranular corrosion and thus the cause of the tube cracking.
The other cause of tube leaks is thought to be tube thinning. Eddy current tests of the tubes have indicated that the thinning occurs on tubes near the tubesheet at levels corresponding to the levels of sludge that accumulates on the tubesheet. The sludge is mainly from oxides and copper compounds along with traces of other metals that have settled out of the feedwater onto the tubesheet. The level of sludge accumulation may be inferred by eddy current testing with a low frequency signal that is sensitive to the magnetic material in the sludge. The correlation between sludge levels and the tube wall thinning location strongly suggests that the sludge deposits provide a site for concentration of a phosphate solution or other corrosive agents at the tube wall that results in tube thinning.
One method for removing sludge from a steam generator is described in U.S. Pat. No. 4,079,701 entitled "Steam Generator Sludge Removal System", issued Mar. 21, 1978 to Hickman et al. and assigned to the assignee of the present invention. In many nuclear steam generators in service today, there are six-inch diameter hand holes in the shell of the steam generator near the tubesheet that provides access to the tubesheet for removal of the sludge deposits on the tubesheet. With the system of Hickman et al., a fluid flushing stream is continuously maintained from a pair of flushing fluid injection nozzles inserted in one of the hand holes of the steam generator, around the annular space between the lower shell of the steam generator and the tube bundle, to a flushing fluid suction apparatus located at a second hand hole which diametrically opposes the first hand hole. While the fluid flushing stream is continuously maintained, a movable fluid lance is placed in the steam generator and moved along the tube lane to dislodge deposits from between the two brews and move the sludge toward and into the annular space where it is entrained in the continuously flowing flushing fluid stream. U.S. Pat. No. 4,276,856 issued to Dent et al. discloses a sludge lance advancing device used in carrying out the above-described process. However, often the pressure blast out of the high-pressure water jet is obstructed by other components of the sludge lance system.
U.S. Pat. No. 4,445,465 discloses a sludge lancing system which alternately directs the entire fluid flow first to the single movable lance for dislodging the sludge from between the tube rail while moving the sludge lance outwardly to the periphery of the tube bundle and then a stationary flushing fluid injector which directs the entirety of the available fluid about the periphery of the tube to flush the sludge which was previously dislodged by the movable lance toward a suction system. However, again, as with the previously discussed device, the pressure blast of the high-pressure water jet may be obstructed by various components of the sludge lance system. Consequently, the pressure blast of the high-pressure water jet may be diminished, thereby resulting in an insufficient amount of pressure to dislodge the settled sludge material. Various additional nuclear steam generator sludge lancing systems have been developed such as those disclosed in U.S. Pat. Nos. 4,715,324 issued to Muller et al. and 4,844,021 issued to Stoss; however, again, as with the above-mentioned prior devices, the pressure blast of the high-pressure water jet may become obstructed by various components of the sludge lance system resulting in the insufficient dislodging of the sludge material.
Therefore, there is clearly a need for a sludge lancing system which overcomes the aforementioned deficiencies found in the prior devices. More particularly, there is a need for a sludge lancing system wherein the half of the pressure blast generated by the high-pressure water jet is unobstructed by any component of the sludge lance system.
SUMMARY OF THE INVENTION
It is a primary object of the present invention to overcome the shortcomings associated with the abovementioned prior devices.
Another object of the present invention is to provide a sludge lancing system which reliably and efficiently dislodges and removes sludge deposits from the upper surface of a tube sheet of a nuclear steam generator.
Yet another object of the present invention is to provide a sludge lancing system which disperses an unobstructed stream of pressurized fluid towards the sludge deposits to dislodge such deposits s that they may be readily removed by a suction device.
A further object of the present invention is to provide a sludge lancing system which minimizes the down time of the nuclear steam generator and which subjects maintenance personnel to a minimal amount of exposure to a contaminated environment.
Another object of the present invention is to provide a sludge lancing system which removes a substantial portion of the sludge deposits created during the operation of a nuclear steam generator so as to minimize the necessity of carrying out such a maintenance procedure and the subsequent down time of the generator, thereby reducing the overall maintenance and operation costs associated with conversion of nuclear energy into usable electricity.
The above objects as well as others are achieved by providing a process and system for removing sludge deposits from the tube sheet of a nuclear steam generator having at least one handhole provided adjacent the tube sheet. The process includes the steps of inserting a suction device through the handhole and into an interior region of the steam generator, inserting a reciprocable fluid injection device supporting structure having a reciprocable carriage positioned thereon through the handhole and into a tube lane within the steam generator adjacent a first side of a plurality of stay rods positioned in the tube lane, securing the supporting structure to at least one of the stay rods, positioning an end of a reciprocable fluid injection device in the carriage, and inserting a peripheral fluid injection device through the handhole and into the tube lane adjacent an opposing side of the plurality of stay rods to a position diametrically opposed to the handhole with the associated elongated tubing being positioned at a point above the reciprocating fluid injection device. The reciprocable fluid injection device is then reciprocated along the tube lane while injecting high pressure fluid towards the tube sheet and injecting high pressure fluid through the peripheral fluid injection device thereby simultaneously drawing dislodged sludge deposits from the interior of the steam generator by the suction device.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a partial cross-sectional view in elevation of a typical steam generator;
FIG. 2 is an elevational view of the sludge lance system in accordance with the present invention positioned within the nuclear steam generator of FIG. 1;
FIG. 3 is an expanded view of the gripping mechanism of the sludge lance system in accordance with the present invention;
FIG. 4 is a top view of the gripping mechanism of FIG. 3 shown in its retracted condition;
FIG. 5 is a top view of the gripping device of FIG. 3 shown in its extended condition;
FIG. 6 is an expanded view of the encircled area VI of FIG. 2 illustrating the interconnection of the sections forming a rail assembly in accordance with the present invention;
FIG. 7 is an expanded elevational view of the carriage assembly mounted on a portion of the rail assembly in accordance with the present invention; and
FIG. 8 is a cross-sectional view taken along line VIII--VIII of FIG. 7.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
In a U-tube type steam generator, a tubesheet supports a bundle of heat transfer U-tubes. During operation, a sludge may form on the tubesheet around the U-tubes causing failure of the tubes. Failure of the tubes results in a release of radioactive particles from the primary reactor coolant into the feedwater of the steam generator. The invention, herein described, is a system for removing the sludge accumulation before it can cause such tube failure.
Referring to FIG. 1, a nuclear steam generator referred to generally as 10, comprises a lower shell 12 connected to a frustoconical transition shell 14 which connects lower shell 12 to an upper shell 16. A dish-shaped head 18 having a steam nozzle 20 disposed thereon encloses the upper shell 16 while a substantially spherical head 22 having an inlet nozzle 24 and an outlet nozzle 26 disposed thereon encloses the lower shell 12. A dividing plate 28 centrally disposed in the spherical head 22 divides the spherical head 22 into an inlet plenum 30 and an outlet plenum 32. The inlet plenum 30 is in fluid communication with inlet nozzle 24 while outlet plenum 32 is in fluid communication with outlet nozzle 26. A tubesheet 34 having tube holes 36 therein is attached to lower shell 12 and the spherical head 22 so as to isolate the portion of steam generator 10 above tubesheet 34 from the portion below tubesheet 34 in a fluid-tight manner. Tubes 38 which are heat transfer tubes shaped with a U-like curvature are disposed in tube holes 36. Tubes 38 which may number about 7,000 form a tube bundle 40. The dividing plate 28 is attached to tubesheet 34 so that inlet plenum 30 is physically divided from outlet plenum 32. Each tube 38 extends from the tubesheet 34 where one end of each tube 38 is in fluid communication with inlet plenum 30, up into the transition shell 14 where each tube 38 is formed in a U-like configuration, and back down to the tubesheet 34 where the other end of each tube 38 is in fluid communication with the outlet plenum 32. In operation, the reactor coolant having been heated from circulation through the reactor core enters the steam generator 10 through inlet nozzle 24 and flows into the inlet plenum 30. From inlet plenum 30, the reactor coolant flows through tubes 38 in the tubesheet 34, up through the U-shaped curvature of tubes 38, down through tubes 38 and into the outlet plenum 32. From the outlet plenum 32, the reactor coolant is circulated through the remainder of the reactor coolant system in a manner well known in the art.
Again referring to FIG. 1, the tube bundle 40 is encircled by a wrapper 42 which extends from near the tubesheet 34 into the region of transition shell 14. Wrapper 42, together with the lower shell 12 form an annular chamber 44. A secondary fluid or feedwater inlet nozzle 46 is disposed on the upper shell 16 above the tube bundle 40. A feedwater header 48 comprising three loops forming a generally cloverleaf-shaped ring is attached to feedwater inlet nozzle 46. The feedwater header 48 includes a plurality of discharge ports 50 arranged in varying arrays so that a greater number of discharge ports 50 are directed toward annular chamber 44 than are directed otherwise.
During operation, feedwater enters the steam generator 10 through the feedwater inlet nozzle 46, flows through and out of the feedwater header 48 through discharge ports 50. The greater portion of the feedwater exiting discharge ports 50 flows down annular chamber 44 until the feedwater contacts the tubesheet 34. Once reaching the bottom of the annular chamber 44 near the tubesheet 34, the feedwater is directed inwardly around the tubes 38 of the tube bundle 40 where the feedwater passes in heat transfer relationship with the tubes 38. The hot reactor coolant in tubes 38 transfers heat through tubes 38 to the feedwater thereby heating the feedwater. The heated feedwater then rises by natural circulation up through the tube bundle 40. In its travel around tube bundle 40, the feedwater continues to be heated until steam is produced in a manner well known in the art.
Referring now to the upper portion of FIG. 1, the wrapper 42 has an upper cover or wrapper head 52 disposed thereon above the tube bundle 40. disposed on the wrapper head 52 are sleeves 54 which are in fluid communication with the steam produced near the tube bundle 40 and have centrifugal swirl vanes 56 disposed therein. Disposed above sleeves 54 is a moisture separator 58 which may be a chevron moisture separator. The steam that is produced near the tube bundle 40 rises through the sleeves 54 where the centrifugal swirl vanes 56 cause some of the moisture in the steam to be removed. From sleeves 54, the steam continues to rise through the moisture separator 58 where more moisture is removed therefrom. Eventually, the steam rises through steam nozzle 20 from where it is conducted through common machinery to produce electricity; again, all in a manner well known in the art.
Referring again to the lower portion of FIG. 1, due to the curvature of tubes 38, a straight line section of tubesheet 34 is without tubes therein. This straight line section is referred to as a tube lane 60. In conjunction with the tube lane 60, two inspection ports 62 (only one is shown) which may be two inches in diameter are provided diametrically opposite each other and in colinear alignment with the tube lane 60. Two additional inspection ports 62 may be located on the lower shell 12 at 90° to tube lane 60. The inspection ports 62 allow limited access to the tubesheet 34 area. In addition to the inspection ports 62, six inch diameter hand holes 64 are also provided.
Experience has shown that during steam generator operation, sludge may form on the tubesheet 34 around the tubes 38. The sludge which usually comprises iron oxides, copper compounds, and other metals is formed from these materials settling out of the feedwater onto the tubesheet 34. As mentioned previously, the sludge produces defects in the tubes 38 which allow radioactive particles in the reactor coolant contained in tubes 38 to leak out into the feedwater and steam of the steam generator. Such an occurrence is highly undesirable.
Referring now to FIG. 2, the nuclear steam generator sludge lancing system of the present invention is illustrated. For the purpose of clarity, the reciprocable sludge lance is not illustrated and may be of the type set forth in U.S. Pat. No. 4,276,856 referred to above or any other type of high pressure spray nozzle. FIG. 2 illustrates the lower portion of the lower shell 12 just above the tubesheet 34. The cross-section view of FIG. 2 is taken through the tube lane 60, and, consequently, there are no tube holes 36 or tubes 38 illustrated. A conventional nuclear steam generator includes a plurality of stay rods 70 and support plates 72 which aid in supporting the tubes 38 of the tube bundle. Also disposed within the lower shell 12 of the nuclear steam generator is a conventional suction header 74 which is initially inserted into the hand hole as is conventional with previous sludge lance operations.
The sludge lance system of the present invention consists primarily of two components, the first being an overhead rail support and delivery assembly 76 and the second being a peripheral flow header assembly 78. The overhead rail support and delivery assembly 76 includes a plurality of rail sections 80 which are interconnected with one another by connections 82 in order to extend the appropriate length into the nuclear steam generator. The connection 82 is best illustrated in FIG. 6 and includes a plurality of detents 84 which act with one another to maintain the telescopic members 80a and 80b interconnected when the members are inserted within one another. As can be seen from FIG. 6, the overhead rail assembly is constructed to include an upper tubular extent 86 and a lower inverted T extent 88. The particular construction of the overhead rail assembly will be discussed in greater detail hereinbelow.
The leading section of the overhead rail support and delivery assembly includes a gripper device 90 which grips a respect of one of the stay rods 70 within the nuclear steam generator. With the present invention, the gripper assembly 90 grips the third stay rod within the nuclear steam generator. Once the appropriate number of sections 80 are interconnected and attached to the handhole handling tool 92 which includes a mounting piece 94 which is formed to receive the periphery of the handhole 64, the overhead rail support and delivery assembly 76 is inserted on a first side of the stay rods 70 and into the tube lane 60. The overhead rail support and delivery assembly 76 is inserted into the tube lane 60 until the gripper assembly 90 is positioned along side a predetermined stay rod. Once in this position, the handhole handling tool 92 is secured to the handhole flange 96. The handhole handling tool 92 may be secured to the handhole flange 96 by a latching mechanism which latches on to a flange bolt already positioned in the hand hole flange 96. The digital end of the overhead rail support and delivery assembly is then adjusted upwardly or downwardly in order to position the overhead rail assembly parallel to the support plate 72. This may be accomplished by either providing a feeler rod at the end of the overhead rail support assembly which when in contact with the support plate 72 positions the overhead rail assembly parallel to the support plate 72 or a leveling indicator within the handhole handling tool 92. Once the overhead rail assembly 76 is positioned parallel to the support plate 72, the gripper assembly 90 is extended in order to grip the predetermined stay rod 70. The gripping assembly 90 is best illustrated in FIGS. 3-5.
Referring now to FIGS. 3-5, the gripper assembly 90 will be described in greater detail. It should be noted that with the preferred embodiment, a pneumatically actuated clamp is provided; however, an electromagnetic or hydraulic gripper assembly may be readily adapted to the present invention.
As mentioned previously, the gripper assembly 90 is a pneumatically actuated gripper assembly and includes the pneumatic master cylinder 98 for selectively retracting and extending the gripper jaws 100 and 102. The cylinder 98 includes leads 104, 106 which supply pneumatic fluid to the cylinder 98. In response to a change in the pressure being supplied to the cylinder 98, the piston rod 108 will retract thereby drawing the slide mechanisms 110 and 112 toward one another. In doing so, the jaws 100 and 102 will be displaced outwardly towards the stay rod. This is carried out by providing cam slots 112 and 114 which each receive a respective cam follower 116 and 118 which as can be seen from FIGS. 4 and 5 push the jaws 100 and 102 outwardly and towards one another upon retraction of the piston rod 108. The slides 110 and 112 are readily received within slots 120 and 122 respectively which allow for the reciprocation of the jaw members 100 and 102. The cylinder 98 is secured to the rail assembly by fixtures 124 above the inverted T rail 88. The slides 110 and 112 are slidably positioned above the inverted rail 88 by bolts 126 which extend through a friction-reducing disc 128 which allows the slides 110 and 112 to reciprocate in response to a change in the pressure being supplied to the cylinder 98.
Returning again to FIG. 2, once the overhead rail support assembly is secured within the tube lane 60 of the nuclear steam generator, the peripheral flow header assembly 78 is inserted into the tube lane 60 parallel to the overhead rail assembly on the opposite side of the stay rods 70.
The peripheral flow header assembly 78 includes upper and lower fluid supply tubes 130 and 132. The fluid supply tubes supply a pressurized fluid, such as water, to a nozzle 134 which shoots jets of water out opposite sides thereof such that the water travels along the inner periphery of the lower section 12 of the nuclear steam generator. The peripheral flow header assembly 78 includes a knee joint 136 which allows the peripheral flow header assembly 78 to pivot at a predetermined point along its length at an angle of approximately 90 degrees so as to properly position the peripheral flow header assembly within the nuclear steam generator. The knee joint includes a fluidic connection for both the upper and lower fluid tubes such that pressurized fluid may continuously flow through the knee joint. The knee joint includes a pair of inlets 138 and a pair of outlets 140. This allows the peripheral flow header assembly 78 to be properly positioned within the nuclear steam generator and further allow an unobstructed flow of fluid to the nozzle 134. The peripheral flow header assembly 78 is inserted through the handhole 64 in a slightly bent condition as is shown by the solid lines in FIG. 2. When the nozzle 134 contacts the opposing inside surface of the lower shell 12 of the nuclear steam generator, the operator will continue to insert the peripheral header assembly 78 such that the nozzle 134 contacts and slides down the inner surface of the lower shell 12 of the nuclear steam generator and rest on an upper surface of the tubesheet 34. In doing so, the peripheral flow header assembly 78 will pivot at the knee joint 136 to a position shown in the hidden lines in FIG. 2. The knee joint thus bends such that the tubes which enter and exit the knee joint 136 are at approximately right angles to one another.
A support clamp (not shown) is then attached to the end of the peripheral flow header assembly 78 which extends through the hand hole 64 and by tightening the support clamp on the tubes 130, 132 of the peripheral flow header assembly 78, the nozzle 134 and the knee joint 136 are pressed against the inside diameter of the lower shell 12 of the nuclear steam generator. By pressing the nozzle 134 and knee joint 136 against the inner diameter of the lower shell 12, the entire horizontal extent of the tubes 130, 132 of the peripheral flow header assembly are caused to bend upwardly approximately two inches which positions the tubes 130, 132 above the inverted T rail 88 of the overhead rail assembly 76. The significance of the particular positioning of the tubes 130, 132 will be explained in greater detail hereinbelow.
Also illustrated in FIG. 2 is a carriage assembly 150 which is positioned to travel along the inverted T rail 88 in response to the extension and retraction of a sludge lance into and out of the tube lane 60 of the nuclear steam generator. The particular structure of the carriage assembly is best illustrated in FIGS. 7 and 8. As can be seen from FIG. 7, the carriage assembly includes an upper mounting section 152 and a lower sludge lance receiving section 154. As can be seen from FIG. 8, the mounting section 152 includes a plurality of bearings 156 which are adapted to be received by and roll along the upper horizontal extent of the inverted T rail 88. The roller bearings 156 are secured to the mounting section 152 by a fastening means 158 which is preferably of the nut-and-bolt type. Flanges 160 are also provided on the leading and trailing ends of the carriage assembly to assure that any debris which may accumulate on the surface of the inverted T rail 88 which would jeopardize the smooth reciprocation of the carriage assembly is removed before reaching the bearings 156.
The receiving section 154 of the carriage assembly is cylindrical in nature and receives the extended portion of the sludge lance tool 162 therein. A button 164 which is spring biased upwardly against the sludge lance tool 162 by a leaf spring 166 applies a pressure against the lower surface of the sludge lance tool such that when the sludge lance tool is extended and retracted into and out of the nuclear steam generator, the carriage assembly will be likewise reciprocated along therewith. The leaf spring 166 is fixed at one end to the cylindrical receiving 154 section of the carriage assembly 150 by a rivet or similar fixing means 168. Thus, the carriage assembly 150 will support the distal end of the sludge lance tool 162 through a majority of its travel into and out of the nuclear steam generator. The particular operation of the carriage assembly will be described in greater detail hereinbelow.
The operation of the sludge lancing system, in accordance with the present invention, is carried out in the following manner. Initially, the overhead rail assembly is inserted into the lower shell 12 of the nuclear steam generator 10 such that the distal end of the overhead rail assembly 76 extends approximately 12 inches beyond the third stay rod 70 with the gripper assembly 90 being positioned adjacent the third stay rod 70. The overhead rail assembly 76 is then fixed at its proximal end to the flange of the hand hole 64 and adjusted such that the overhead rail assembly 76 extends substantially parallel to the lowermost support plate 72 of the nuclear steam generator 10. Once in this condition, the gripper assembly 90 is actuated such that gripper jaws 100 and 102 securely grasp the third stay rod 70 and fix the overhead rail assembly 76 in its appropriate position. It should be noted that the carriage assembly 150 is to be initially mounted onto the inverted T rail 88 of the overhead rail assembly 76 and positioned adjacent the proximal end of the overhead rail assembly 76.
The peripheral flow header assembly 78 having a knee joint positioned at a predetermined point along the length thereof is inserted in a slightly bent condition through the hand hole 64 of the nuclear steam generator 10. The insertion of the peripheral flow mounted assembly 78 is continued until the nozzle 134 headed on the distal end of the peripheral flow header assembly 78 contacts the inner wall of the lower shell 12 of the nuclear steam generator 10. The operator then continues the insertion of the peripheral header assembly until the knee joint abuts the inside wall of the lower shell 12, thus positioning the tubes 130, 132 which enter and exist the knee joint at approximately right angles to one another. Once in this position, the tubes which extend from the proximal end of the peripheral flow header assembly 78 are clamped by a support clamp 97. When the support clamp 97 is tightened, the horizontal extent of the tubes 130 and 132 of the peripheral flow header assembly 78 are caused to bend upwardly a distance of approximately two inches which thus positions the tubes 131 and 132 of the peripheral flow header assembly above the carriage assembly 150. A sludge lance is then positioned within the receiving section 154 of the carriage assembly 150 and extended into the tube lane 60 of the nuclear steam generator 10. The carriage assembly 150 frictionally engages the distal end of the sludge lance tool 162 and thus is reciprocated along the inverted T rail 88 in response to the movement of the sludge lance tool 162. The distal end of the sludge lance tool is thus carried along the overhead rail assembly 76 by the carriage assembly 150 until the carriage assembly reaches a stop 170 at the end of the overhead rail assembly 76. At this point, the operator continues to insert the sludge lance tool which will then slide through the carriage assembly for the remaining approximately 40 inches of travel until the full extent of the sludge lance tool is extended into the steam generator. Once the sludge lance 162 has reached its furthest extent, it is then retracted through the handhole 64 and is supported by the carriage assembly 150 during its retraction. It is to be noted that during the complete insertion and retraction of the sludge lance tool 162 into and out of the nuclear steam generator, there are no parts of the sludge lance system which would obstruct the flow of pressurized fluid through the nozzle of the sludge lance tool 162 because the sludge lance tool 162 is supported by the overhead rail assembly 76 and the peripheral flow header assembly 78 is positioned at a point above the sludge lance tool 162. Therefore, the sludge lance tool 162 can effectively remove the sludge deposits from the surface of the tubesheet without obstruction from the remaining components of the sludge lancing system.
While the present invention has been described with reference to a preferred embodiment, it will be appreciated by those skilled in the art that the invention may be practiced otherwise and as specifically described herein without departing from the spirit and scope of the invention. It is, therefore, to be understood that the spirit and scope of the invention be limited only by the appended claims. | A process and system for removing sludge deposits from a tube sheet of a steam generator having at least one handhole provided adjacent the tube sheet is disclosed. The process includes the steps of inserting a suction device through the handhole and into an interior region of the steam generator, inserting a reciprocable fluid injection device supporting structure having a reciprocable carriage positioned thereon through the handhole and into a tube lane, within the steam generator adjacent a first side of a plurality of stay rods positioned in the tube lane, securing the supporting structure to at least one of the stay rods, positioning an end of a reciprocable fluid injection device in the carriage, inserting a peripheral fluid injection device through the handhole and into the tube land adjacent an opposing side of the plurality of stay rods to a position diametrically opposed to the handhole, and reciprocating the reciprocable fluid injection device along the tube land while injecting high pressure fluid towards the tube sheet with the reciprocable fluid injection device, injecting high pressure fluid through the peripheral fluid injection device and drawing dislodged sludge deposits from the interior of the steam generator by the suction device. | 5 |
[0001] The present application claims priority to U.S. Provisional Patent Application No. 60/332,571 and to German Patent Application No. 100 56 259.6 filed Nov. 14, 2000.
BACKGROUND OF THE INVENTION
[0002] The invention pertains to a paint transfer-valve device for connecting a number of paint lines for coating material of different, selectable paints with an application element according to the upper clause of claim 1, and also to a method for control of this type of device.
[0003] Paint transfer valve devices, or briefly, paint changers, in painting or lacquering systems for coating of workpieces, such as motor vehicle chassis during the lacquering process, make possible a rapid switching from one paint to another, and consist primarily of a number of controllable paint valves which are distributed along a paint conduit carrying all paints. For adaptation to the particular painting system and the number of selectable paints, they are designed in a block construction from individual modules (connection blocks, connection strips, control heads) which can be lined up together, so that a variable, subsequently enlargeable or reducible number of connections for paint lines can be obtained. In addition to the paint valves, usually other, similarly constructed valves are provided for rinsing media, such as thinner fluids and pulsed air.
[0004] Known paint changers of this kind (Duerr, Technical Handbook, Introduction to the technology of passenger vehicle lacquering, April 1999) contain pneumatically actuated valves which are operated by compressed air signals from the valves of individually allocated hoses. These control-air hoses come from a distant pneumatic cabinet, where they are each opened and closed by a magnetic valve under the control of the electronic control system of the apparatus for generation of the compressed air control signals.
[0005] The known pneumatic control system is very complicated, since for each switching function, one compressed air hose has to be laid from the pneumatic cabinet to the paint changer, and in addition, for each valve of the paint changer, and structurally and spatially separate, an external electromagnetic valve is needed. Furthermore, due to the control air hoses and the requirement for them to be compressed and relieved, switching delays of differing time length will occur, since depending on the particular installation (e.g., for side and roof machines), different hose lengths and accordingly different switching times will result within the system. Short and precisely-defined switching times are important, especially for newer rinsing programs for paint changers, where the opening times of the rinsing valves are typically on the order of fractions of a second (DE 199 51 956).
[0006] From EP 0 979 964 A, it is already known how to operate the valve needle of the paint control valves of a paint changer by electromagnetic means in order to use a direct electrical bus control to achieve the shortest possible switching times without the hoses needed for pneumatic control. But for a direct operation of the valve needle, relatively powerful electromagnets are required, which provide the needed blocking, but also may have undesirable, large electrical power consumption, which is particularly troublesome under consideration of the regulations on explosion prevention.
SUMMARY OF THE INVENTION
[0007] It is the purpose of the invention to specify a paint changer and a method for its control, which avoids the conduit outlay and the switch time latency of pneumatically controlled paint changers, without the requirements for the less desirable, powerful electromagnets.
[0008] This purpose is achieved by the properties of the independent patent claims.
[0009] Due to the invention, a compact and dependable unit is created which will require far lower installation and other expenses in comparison to standard pneumatically controlled paint changers. In particular, the formerly required, numerous control air hoses of the paint changer and also the large external pneumatic cabinet including its magnetic valves are omitted. Since the pressurizing and venting of hose lines is now omitted, much faster switching processes will result, which can additionally be determined accurately and are independent of the installation, so that often highly reproducible rinsing programs can be obtained with short switching times.
[0010] The installation expense will also be reduced because only electric lines are connected to the paint changer, in addition to the compressed air hose for pneumatic pilot control which is common to all valves. And in the preferred data bus controller, only this bus and a power supply line for the electromagnets and for the electronic control circuits of the valves are needed.
[0011] These advantages are combined according to this invention, with an efficient pneumatic valve actuation, so that a powerful electromagnetic drive is not needed. In addition, the invention has the advantage that the purely pneumatic valves in the paint changer, common today, can be easily replaced without other design changes by the new, electrically controlled valves.
BRIEF DESCRIPTION OF THE FIGURES
[0012] [0012]FIG. 1 shows a schematic of the color paint changer of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0013] Using the design example shown in the figure, the invention will now be explained in greater detail. The figure schematically shows a paint changer with pneumatic valves controlled electronically by a field bus system.
[0014] The paint changer 1 consists in known manner of a modularly expandable or reducible group of sequential block units, each composed of housing elements 2 and, e.g., screwed in valves 3 for attaching therein paint lines and rinsing lines (not illustrated) to the mounted central paint conduit.
[0015] The valves 3 pertain to pneumatic valves pilot-controlled by an electromagnetic valve. Suitable designs for this are already well known to an ordinary technician skilled in the art, depending on the particular application. For example, the valves 3 can contain a pneumatic base unit corresponding to FIG. 2 of the aforementioned EP 0 979 964 A, in which a valve needle equipped with a piston is pressed by compressed air against the force of a spring into an open position, in which it releases the pathway for the paint or rinsing medium in the paint conduit of the paint changer. But whereas in the known case, the compressed air represents the control signal for opening and closing of the paint valve, in the paint changer described here, the compressed air connection is replaced by an electromagnetic valve unit 11 which is attached to the pneumatic base unit and electrically opens and closes the connection between a compressed air line 4 , permanently under a continuous pressure, and the pneumatic base unit. Under consideration of the design, the attached electromagnetic valve unit 11 can be configured similar to the already known pneumatic base unit and, for example, can contain a magnetic core moving as its needle 12 , to which a sealing seat is provided. If the magnetic core is attracted by an electric coil surrounding it, then the sealing seat will open and release the pathway for the compressed air from the line 4 into the pneumatic base unit. The compressed air line 4 used for pneumatic pilot control and connected at point P to a central pilot control air supply, runs through the housing element 2 of the paint changer 1 and is connected to all valves 3 within the paint changer. But instead of this, other known or expedient designs can be used for an electrically controlled valve for opening and closing of the pneumatic lines of the paint and rinsing agent valves.
[0016] In particular, when the known pneumatic valves 3 of the previously used paint changer are each provided with a directly attached electromagnetic pilot control valve 11 , then by use of an additional sensor per valve, the switch setting of the valve can be indicated and/or reported back to an electronic control system 7 .
[0017] For electrical control of the valves 3 , we use preferably an internal data bus 5 passing through all modular housing elements 2 , and this can be a CAN-bus or any of the other known, standardized bus systems, and is connected via an interface 6 to the higher-order electronic control system 7 . Preferably, one of the modern field bus systems is used whose binary control data are allocated in the paint changer 1 to valves 3 to which they are respectively assigned. For allocation and addressing, electronic circuits (chips) are used in a known manner; they can be provided in the individual valves in order to link the mentioned coils of the electromagnetic valve units 11 for opening of the particular valve with a power supply line 8 , likewise running through the entire paint changer. Due to the low power consumption of the electromagnet valve units 11 now possible according to this invention, they can be driven from the electrical control directly with accordingly smaller output power.
[0018] Preferably, the modular block units are each formed from a housing element 2 and one or more valves 3 and can be easily plugged together for adaptation of the particular quantity of selectable paints, where the necessary strength is ensured by suitable locking features. In this configuration, the sections of the internal data bus 5 extending through the modular housing units are joined together by plug-in contacts 9 . The same also applies to the corresponding sections of the power supply line 8 and the compressed air line 4 .
[0019] Since paint changers in electrostatic coating systems usually have to be grounded, the housing parts of the paint changer 1 can consist of an electrically conducting material, for example, a conducting plastic.
[0020] Instead of the described bus control, single wiring of the electromagnetic valves is also possible, so that only the pilot control compressed air line will lead to the paint changer.
[0021] The invention has been described in an illustrative manner, and it is to be understood that the terminology which has been used is intended to be in the nature of words of description rather than of limitation.
[0022] Obviously, many 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, wherein reference numerals are merely for convenience and are not to be in any way limiting, the invention may be practiced otherwise than as specifically described. | The paint and rinsing-agent valves of a paint changer for connection of a number of paint lines for coating material of different, selectable paints with an application element are pilot-controlled pneumatically by a compressed air line common for all valves and placed permanently under pressure, and switched by attached electronically controlled electromagnetic valves. The electronic control takes placed by means of a field bus system electronically interfaced with each of the paint and rinsing-agent valves. | 1 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to an optical disk recording and reproducing apparatus for recording and reproducing information on an optical disk. More specifically, the invention relates to an optical disk recording and reproducing apparatus with a focus servo system.
2. Description of the Background Art
In order to facilitate a better understanding of the features of the present invention in relation to the background art, a brief discussion will be provided about the background art of the present invention with reference to FIGS. 1 and 2, which illustrate a circuit diagram of an optical disk recording and reproducing apparatus of the prior art.
The shown optical disk recording and reproducing apparatus of FIG. 1 is designed for recording and reproducing information on tracks formed on an optical disk 1. As is well known, the optical disk is chucked on a disk drive mechanism including a motor driven spindle 2 which is driven by a spindle motor for rotatingly driving the disk. As shown in FIGS. 2 and 2A, the optical disk to be used in the shown apparatus is a so-called "pre-grooved type disc" which has a plurality of recording tracks defined by preliminarily formed grooves. In addition, as a recordable optical disk, the shown embodiment employs an optomagnetic disk. The disk 1 chucked on the spindle 2 is thus driven at a given constant speed.
An optical head 3 is provided in the vicinity of the optical disk for optically reading or writing information on the recording tracks. The optical head 3 is connected to an RF circuit 4. The RF circuit 4, operating in a reproducing mode, converts the information read from the recording track by means of the optical head 3 into an electric signal indicative of the read information to output. On the other hand, the RF circuit 4, operating in a recording mode, converts the information containing an electric signal into optical information data in a form recordable on the recording track.
This RF circuit 4 is connected to a signal processing circuit 5. This signal processing circuit 5 performs a known signal processing operation. The signal processing circuit 5 is connected to an input/output circuit 6.
The RF circuit 4 also outputs a focus error signal to a focus servo circuit 7 to feed thereto a focus error signal. The RF circuit 4 is further connected to a tracking servo circuit 8 to feed a tracking error signal. The output of the focus servo circuit 7 is connected to the optical head 3. The output of the focus servo circuit 7 is also connected to a thread servo circuit 9 which controls transverse shift of the optical head 3.
Operation of the signal processing circuit 5, the focus servo circuit 7, a tracking servo circuit 8 and a thread servo circuit 9 are connected to a CPU 10 which serves as a system controller. The CPU 10 outputs a clock signal, a timing signal, an access signal and so forth. The CPU also outputs control signals for the aforementioned respective circuits for controlling operations thereof depending upon the operation modes thereof. The CPU also serves to control the driving speed of the spindle motor for controlling rotation speed of the optical disk 1.
As shown in FIGS. 2 and 2(A), the grooves G are formed on the disk in concentric circular or helical fashion. The grooves will be hereafter referred to as "pre-grooves". Each pre-groove G has a width corresponding to where λ/8 (λ is the wavelength of laser of the optical head). An adjacent pair of grooves G define a land which serves as a recording track T. As will be appreciated, the light intensity to be reflected from the pre-groove G and the land T is different from each other. Based on the difference of light intensity reflected from the groove and the land, a tracking error signal is generated so that a tracking servo system will control the optical head to place the light spot of the laser beam on a desired one of tracks for tracing therealong.
In such optical disk recording and reproducing apparatus, the reflected light intensity frequently varies every time the laser beam spot moves across the pre-groove during a search operation, in which the optical head is shifted transversely to the tracks. As a result, a high frequency signal St modulated by the pre-grooves, which is shown in FIG. 3(a) and will be hereafter referred to as "traverse signal", tends to be superimposed on the focus error signal.
The focus servo circuit 7 in FIG. 1 employs a phase compensation circuit 71 (FIG. 4) for enhancing a high frequency component of the focus error signal St for improving response characteristics. The output of the phase compensation circuit 71 is fed to a driver circuit 72. The driver circuit 72 generates a drive signal S FD for driving a focus actuator 73.
In this circuit arrangement, when the traverse signal superimposes on the focus error signal St, the traverse signal may be enhanced in the focus servo loop set forth above. As a result, the peak of the enhanced focus error signal tends to saturate to cause distortion of the waveform in the drive signal S FD , as shown in FIG. 3(b). This distortion of the waveform of the drive signal S FD causes variation of the direct current level. Variation of the direct current level tends to degrade the accuracy of a focusing operation of the focus servo system.
SUMMARY OF THE INVENTION
Therefore, it is an object of the present invention to provide an optical disk recording and reproducing apparatus which can effectively and stably eliminate influence of a traverse signal for accurate focus control.
In order to accomplish the aforementioned and other objects, an optical disk recording and reproducing apparatus, according to the present invention, is provided with a signal processing circuit in a focus servo circuit for suppressing a traverse signal which has a frequency determined by the pitch of pre-grooves and the transversely shifting speed of a laser beam spot and modulates a focus error signal otherwise, during a search mode operation.
This signal processing circuit successfully avoid influence of the traverse signal for focus servo system and thus assures accurate focus control. According to one aspect of the invention, an optical disk recording and reproducing apparatus comprises an optical head scanning a light beam on an optical disk formed with a plurality of essentially circumferentially extending grooves for reproducing an information signal including a focus error signal, a focus servo system including a focus actuator operable for driving an object lens of the optical head for focusing a light beam on the optical disk, means associated with the focus actuator for deriving a focus control signal on the basis of the focus error signal in order to control the focus actuator, and means, active in an access mode operation of the optical disk recording and reproducing apparatus in which light beam shifts transversely across at least one of the grooves, for removing a signal component modulated by the groove, superimposing on the focus error signal.
According to another aspect of the invention, a focus control system for an optical disk recording and reproducing apparatus including an optical head scanning a light beam on an optical disk formed with a plurality of essentially circumferentially extending grooves for reproducing an information signal including a focus error signal and a focus servo system including a focus actuator operable for driving an object lens of the optical head for focusing a light beam on the optical disk, comprises a focus control signal generator means, associated with the focus actuator, for deriving a focus control signal on the basis of the focus error signal in order to control the focus actuator, and a traverse signal component absorbing means, provided upstream of the focus control signal generator, for absorbing fluctuation of the focus error signal within a predetermined fluctuation range in order for removing a traverse signal superimposing on the focus error signal.
The signal component removing means comprises a deadband circuit and a sample/hold circuit, the deadband circuit defining a deadband for the focus error signal for absorbing fluctuation of the focus error signal within the deadband so as to hold a held value in the sample/hold circuit unchanged.
The focus control system further comprises means for adjusting-the deadband. The deadband adjusting means detects of the level of the signal component for adjusting the width of the deadband depending thereon. The deadband adjusting means detects the signal component superimposing on an output of the sample/hold circuit for adjusting the deadband.
In addition, the focus control system further comprises means for defining a signal path by-passing the deadband circuit for directly feeding an input focus error signal to the sample/hold circuit, the signal path including a switch operable between a conductive state for establishing the path and a non-conductive state for establishing the path and a non-conductive state for breaking the path and switching at the conductive state in response to a signal indicative of one of a tracking On state and focus search state.
According to a further aspect of the invention, a focus control system for an optical disk recording and reproducing apparatus including an optical head scanning a light beam on an optical disk formed with a plurality of essentially circumferentially extending grooves for reproducing information signal including a focus error signal and a focus servo system including a focus actuator operable for driving an object lens of the optical head for focusing a light beam on the optical disk, comprises a focus control signal generator means, associated with the focus actuator, for deriving a focus control signal on the basis of the focus error signal in order to control the focus actuator, and a focus error smoothing means, disposed upstream of the focus control signal generator, for smoothing the focus error signal for removing a traverse signal superimposing on the focus error signal.
The focus error signal smoothing means comprises a peak hold circuit for holding a peak value of the focus error signal, a bottom hold circuit for holding a bottom of the focus error signal and an adder adding outputs of the peak and bottom hold circuits. The peak and bottom hold circuits respectively include diodes and the apparatus further comprises means for compensating for non-linear characteristics of the diodes.
In this case, the focus control system also comprises means for defining a signal path by-passing the focus error signal smoothing means for directly feeding an input focus error signal to the sample/hold circuit, the signal path including a switch operable between a conductive state for establishing the path and a non-conductive state for establishing the path and a non-conductive state for breaking the path and switching at the conductive state in response to a signal indicative of one of a tracking On state and a focus search state.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will be understood more fully from the detailed description given herebelow and from the accompanying drawings of the preferred embodiment of the invention, which, however, should not be taken to limit the invention to the specific embodiment but are for explanation and understanding only.
In the drawings:
FIG. 1, as preceedingly discussed, is a schematic block diagram of an optical disk recording and reproducing apparatus which constitutes background art of the present invention;
FIG. 2 is a plan view of a pre-groove type optical disk to be used in the optical disk recording and reproducing apparatus of the background art of FIG. 1 and of the preferred embodiment of the invention while FIG. 2A is an enlarged portion of FIG. 2;
FIGS. 3(a) and 3(b) show waveforms of a focus error signal and a drive signal in a focus servo system;
FIG. 4 is a block diagram of a focus servo circuit employed in the prior proposed optical disk recording and reproducing apparatus of FIG. 1;
FIG. 5 is a circuit diagram of a traverse signal eliminating circuit and control circuit which forms the major part of the first embodiment of an optical disk recording and reproducing apparatus according to the invention;
FIG. 6 is a graph showing input/output characteristics of an deadband circuit associated with the traverse signal eliminating-circuit of FIG. 5;
FIGS. 7(a) and 7(b) show waveforms of focus error signals St;
FIG. 8 is a circuit diagram of another embodiment of a traverse signal eliminating circuit to be employed in the optical disk recording and reproducing apparatus of the invention;
FIGS. 9(a), 9(b), 9(c), 9(d) and 9(e) are waveforms of signals produced in various components in the traverse signal eliminating circuit of FIG. 8;
FIGS. 10 and 11 are graphs showing input/output characteristics of the deadband circuit associated with the traverse signal eliminating circuit of FIG. 8;
FIG. 12 is a chart showing waveforms of a focus error signal and output of a sample/hold circuit employed in the traverse signal eliminating circuit of FIG. 8;
FIG. 13 is a further embodiment of a traverse signal eliminating circuit to be employed in the preferred embodiment of the optical disk recording and reproducing apparatus according to the invention;
FIGS. 14(a) and 14(b) are waveforms in the circuit of FIG. 13; and
FIG. 15 is a modification of the traverse signal eliminating circuit of FIG. 13.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the preferred embodiments of the present invention, and particularly to FIG. 5, a traverse signal eliminating circuit 11 is interposed between an RF circuit 4 (shown in FIG. 1) and a phase compensation circuit 71 (shown in FIG. 4). The traverse signal eliminating circuit 11 includes an operational amplifier 111 which forms a voltage follower circuit. The operational amplifier 111 has a non-inverting input terminal connected to the RF circuit 4 to receive therefrom a focus error signal St. The operational amplifier 111 also has an inverting input terminal connected to the output of the operational amplifier to constitute a voltage follower circuit.
The output of the operational amplifier 111 is also connected to a deadband circuit 112. The deadband circuit 112 is connected to the phase compensation circuit 71 via a sample/hold circuit 116 which comprises a resistor 113, a capacitor 114 and an operational amplifier 115 which form a voltage follower circuit.
The deadband circuit 112 comprises a pair of diodes 117 and 118. The pair of diodes 117 and 118 are arranged in parallel relationship to each other and in opposite polarity. This deadband circuit 112 is designed to cancel the traverse signal superimposing on the focus error signal St with a potential difference of the rising voltage of the diodes.
Namely, a held voltage V H of the sample/hold circuit 116 is normally applied to the non-inverting input terminal of the operational amplifier 115. When the input voltage V FE to the deadband circuit 112 which contains the traverse superimposing signal, fluctuates in a fluctuation range (V H -V FE ) smaller than the rising voltage V D1 or V D2 of the diodes 117 and 118, both of the diodes are held OFF. Therefore, the held voltage V H of the sample/hold circuit 116 is transferred to the phase compensation circuit 71.
On the other hand, when the voltage fluctuation range (V H -V FE ) is greater than the rising voltage of the diodes 117 and 118, both diodes turn ON. By this the held voltage V H is varied in a magnitude corresponding to a difference of voltage determined by subtracting the riding voltage V D1 or V D2 of the diodes 117 or 118 from the fluctuated voltage (V H -V FE ).
As will be appreciated, with the arrangement set forth above, when the input voltage V FE fluctuates in relation to the held voltage V H , the held voltage will not be varied as long as the voltage fluctuation is in a range define by the rising voltages V D1 and V D2 of the diodes 117 and 118. This voltage fluctuation range will be hereafter referred to as "deadband". The traverse signal superimposing on the focus error signal St is successfully removed utilizing this deadband.
It should be noted that the input/output characteristics of the deadband circuit 112 are shown in FIG. 6. As will be seen from FIG. 6, the opposite connection of the diodes 117 and 118 will provide a substantially great absorption magnitude for small level signals, i.e. for the signals in a range of V D1 and V D2 .
The foregoing deadband circuit 112 is associated with a control circuit 120 which controls the deadband circuit between an active state and an inactive state. In order to control the deadband circuit operational state between an active state and an inactive state, a switch 119 is provided. The control circuit 120 has input terminals 121 and 122 which are connected to a system controller (not shown). When a HIGH level input is applied to one of the input terminals 121 and 122, the switch 119 is operated to an open state to make the deadband circuit 112 inactive.
The input level at the input terminal 121 represents an operational state of the tracking servo system and is held HIGH while the recording and reproducing apparatus operates in a reproduction mode and thus the tracking servo system is an ON state. This turns the switch 119 ON to establish a by-pass circuit for by-passing the focus error signal S t through the switch 119. Similarly, the input level of the input terminal 122 represents a focus search operational state. When a focus search is ON, a HIGH level input is applied to the input terminal 122. By this, both of transistors 123 and 124 are turned ON to turn the switch 119 ON. This establishes the by-pass circuit for by-passing the focus error signal S t through the switch 119.
On the other hand, when the optical head is driven transversely to the tracks on the optical disk in a search mode operation, the tracking servo system turns into an OFF position to apply a LOW level to the input terminal 121. As a result, the transistor 123 is turned OFF to turn the switch 119 OFF. Therefore, the by-pass circuit through the switch 119 is broken to apply the focus error signal St to the deadband circuit 112. At this time, since the input/output characteristic of the deadband circuit 112 is as illustrated in FIG. 6, the focus error signal St (shown in FIG. 7(a)) as the input of the deadband circuit is absorbed as to the superimposing traverse signal component to output the signal having a waveform shown in FIG. 7(b). Since the output of the deadband circuit 112 shown in FIG. 7(b) has successfully removed the traverse signal component, the driver circuit 72 will never become saturated by the output of the phase compensation circuit 71.
On the other hand, at a ON setting of the recording and reproducing apparatus, or when the focus servo becomes an output of control, a focus search signal is applied to a driver circuit 72 for driving an object lens vertically for focus control. During a focus search, a HIGH level signal is applied to the input terminal 122 from the system controller. In response to the HIGH level input at the input terminal 122, the transistor 124 turns ON. This raises the output level of a differential amplifier 125 to turn the switch 119 ON. This establishes the aforementioned by-pass circuit through the switch 119 to pass the focus error signal St to the phase compensation circuit therethrough. Therefore, a focus search can be done accurately and precisely.
In the aforementioned first embodiment of the optical disk recording and reproducing apparatus, the deadband circuit is designed to be active only when the optical head is driven transversely to the tracks of the optical disk to shift the laser beam spot transversely across the pre-grooves, for absorbing or removing the traverse signal which can superimpose on the focus error signal. In other words, since the deadband circuit is held inactive while the tracking servo is ON. This avoids a possibility to activate the focus servo system in an off-focused condition due to an influence of the deadband circuit.
FIG. 8 shows another embodiment of the traverse signal eliminating circuit according to the invention. The shown embodiment of the traverse signal eliminating circuit is generally represented by the reference numeral 220. A deadband circuit 223 comprises a pair of diodes 217 and 218 and resistors 221 and 222 which are connected in series to associated ones of the diodes. Similarly to the former embodiment, the diodes 217 and 218 are arranged in parallel and in opposite polarity. The resistors 221 and 222 are provided with a resistance of R 1 . A current source 225 is respectively connected to a junction between the series of the diode 217 and the resistor 221. Similarly, a current source 226 is connected to a junction between the series of diode 218 and the resistor 222. The current sources 225 and 226 are adapted to supply currents of I 1 and I 2 respectively. The currents I 1 and I 2 of the current sources 225 and 226 serve for causing a voltage drop V R1 and V R2 at the resistors 221 and 222 so as to apply an offset voltage (V FE -V.sub. R1, V FE +V R2 ) relative to the input voltage V FE to the diodes 217 and 218.
Therefore, the diodes 217 and 218 turn ON when the following formulae are established:
V.sub.D1 <(V.sub.FE -V.sub.R1)-V.sub.H (1)
V.sub.D2 <V.sub.H -(V.sub.FE +V.sub.R2) (2)
The foregoing formulae (1) and (2) are modified as:
V.sub.D1 +V.sub.R1 <V.sub.FE -V.sub.H (3)
-(V.sub.D2 +V.sub.R2)>V.sub.FE -V.sub.H (4)
As will be seen from the foregoing formulae, the diodes 217 and 218 turn ON when the fluctuation magnitude of the input voltage V FE becomes out of the range defined by (V D1 +V R1 ) and -(V D2 +V R2 ). When the diodes 217 and 218 turn ON, the held voltage V H of a sample/hold circuit 216 varies. In other words, as long as the fluctuation magnitude of the input voltage V FE is maintained within the range defined by (V D1 +V R1 ) and -(V D2 +V R2 ), the held voltage V H can be held constant.
Here, as will be seen, since the deadband in a range defined by (V D1 +V R1 ) and -(V D2 +V R2 ) is variable depending upon the voltage drop V R1 and V R2 , it can be adjusted by adjusting the currents I 1 and I 2 to be applied from the current sources 225 and 226.
In the shown embodiment, the current sources 225 and 226 are designed to vary the output currents I 1 and I 2 depending upon the level of the traverse signal. This adjusts the deadband range depending upon the traverse signal level for assured by remaining of the traverse signal, superimposing on the focus error signal and preventing the focus error signal level from being excessively lowered.
For this purpose, a high-pass filter circuit 232 which comprises a capacitor 230 and a resistor 231 is connected to the output of the sample/hold circuit 216 in order to receive focus error signal St 1 output therefrom. The high-pass filter 232 extracts the traverse signal S M1 from the focus error signal St 1 . The traverse signal S M1 extracted by the high-pass filter 232 is fed to a full-wave rectification amplifier 233. As a result, when the traverse signal S M2 superimposed on the focus error signal, as shown in FIG. 9(a), is input to the traverse signal eliminating circuit 220, and when the traverse signal S M2 causes the input signal fluctuation beyond the deadband defined in the deadband circuit 223, the excess magnitude of the traverse signal S M1 is extracted by the high-pass filter circuit 232 and input to the full-wave rectification amplifier 233.
The full-wave rectification amplifier 233 comprises an input resistor 234, a feedback resistor 235 and an operational amplifier 237 including a rectification diode 236. The resistance of the input resistor 234 and the feedback resistor 235 are set at an equal value. With this circuit arrangement, the full-wave rectification amplifier 233 outputs a full-wave rectified output signal S MA , as shown in FIG. 9(c). The output signal S MA of the full-wave rectification amplifier 233 is fed to an envelop detector circuit 243 which comprises a resistor 241, a capacitor 242 via an operational amplifier 240. As will be seen from FIG. 8, the envelop detector circuit 243 is in a form of a low-pass filter. Through this envelop detector circuit 243, an envelop signal S E (shown in FIG. 9(d)) can be obtained from the traverse signal S M1 extracted by the high-pass filter 232.
The foregoing high-pass filter 232, the full-wave rectification amplifier 233, the operational amplifier 240, and the envelop detector circuit 243 form a traverse signal detector circuit.
The output of the envelop detector circuit 243 is connected to an inverting amplifier 248. The inverting amplifier 248 comprises an operational amplifier 247 having an input resistor 245 and a feedback resistor 246. The input resistor 245 and the feedback resistor 246 are provided with the same resistance value. With this arrangement, the inverting amplifier 248 receives the envelop signal S E as the output of the envelop detector circuit 243 and inverts the received envelop signal to provide an output to the current source circuits 225 and 226. Here, assuming the voltage level of the traverse signal S M1 input to the inverting amplifier 248 is Vc, the voltage level of the envelop signal becomes -Vc.
The current source circuit 225 includes an operational amplifier 253 having an inverting input terminal, a non-inverting input terminal and an output terminal. A feedback resistor 250 is disposed between the non-inverting input terminal and the output terminal. On the other hand, a feedback resistor 252 is disposed between the inverting input terminal and the output terminal. The non-inverting input terminal of the operational amplifier 253 is also connected to a reference voltage source 257 comprising a resistor 255 and a temperature compensation diode 256, to receive therefrom a reference voltage V D3 . On the other hand, the inverting input terminal of the operational amplifier 253 is connected to the inverting amplifier 248 to receive the inverted envelop signal via a resistor 258. The output terminal of the operational amplifier 253 is connected to the resistor 221 of the deadband circuit 223 via an output resistor 251 to supply the current I 1 . The resistance of the output resistor 251 is set at a value equal to the resistance R 1 of the resistor 221. On the other hand, the resistances of the feedback resistors 250 and 252 and the input resistors 254 and 258 are selected to be the equal in values to R 2 and to each other. With this circuit arrangement, the following equation can be established at the output resistor 251 with respect to input voltages Vc and V D3 and the output current I 1 :
I.sub.1 R.sub.1 =Vc-V.sub.D3 (5)
On the other hand, the voltage drop V R1 at the resistor 221 in relation to the current I 1 can be illustrated by:
V.sub.R1 =R.sub.1 I.sub.1 (6)
Therefore, the voltage drop V R1 can be illustrated by:
V.sub.R1 =Vc-V.sub.D3 (7)
From the foregoing result, the voltage V F1 defining the deadband and determined by the resistor 221 and the diode 217 can be illustrated by: V F1 =V D1 +V R1 =V D1 +Vc-V D3 (8)
Assuming the diodes 217, 218 and 256 are provided with the same rising voltage, the following equation can be derived from the foregoing equation (8):
V.sub.F1 =Vc (9)
Therefore, the voltage V F1 defining the deadband, which voltage is determined by the diode 217 and the resistor 221, can be controlled in proportion to the output voltage Vc.
On the other hand, the current source circuit 226 has an operational amplifier 264 having a non-inverting input terminal, an inverting input terminal and an output terminal. A feedback resistor 260 is connected to the output terminal via a resistor 261 at one end and to the non-inverting input terminal at the other end. On the other hand, a feedback resistor 262 is disposed between the output terminal and the inverting input terminal. The non-inverting input terminal of the operational amplifier 264 is also connected to the reference voltage source 257 via an input resistor 265. The inverting input terminal is, on the other hand, connected to the inverting amplifier 248 to receive therefrom the inverted envelop signal -Vc. In the shown circuit construction, the resistor 261 serves as an output resistor. This output resistor 261 has a resistance R 1 which is the same as that of the resistor 222. On the other hand, the resistances of the feedback resistors 260 and 262 and the input resistors 265 and 266 are set at the same value R 2 .
With this circuit arrangement, the current source circuit 226 generates a current having the same amplitude as, and an opposite polarity to current i 2 . As set forth, this current I 2 is applied to the resistor 222.
As will be appreciated, since the same or similar equations as discussed with respect to the current source circuit 225, apply the following relationship can be established: ##EQU1## As will be appreciated herefrom, as controlled by the opposite polarity and the same amplitude of current I 2 , the voltage V F2 having the identical voltage value and having an opposite polarity, to define the deadband can be obtained, and can be controlled.
The current source circuits 225 and 226, the inverting amplifier 248 and the reference voltage source 257 constitute a deadband control circuit for controlling the width of the deadband according to the level of the envelop signal S E . Furthermore, in the shown embodiment, the diodes 217 and 218 in the deadband circuit are provided with the same characteristics to that of the temperature compensation diode in the reference voltage source 257. Since a closed loop is formed as a whole of the traverse signal eliminating circuit for controlling the width of the deadband, temperature characteristics of the diodes 217 and 218 can be stably and effectively compensated for practical use.
As will be appreciated herefrom, the shown embodiment extracts the traverse signal maintained in the focus error signal St output from the sample/hold circuit, and controls the width of the deadband by adjusting the voltages V F1 and V F2 . Therefore, a traverse signal can be effectively removed or absorbed from the focus error signal to obtain the waveform shown in FIG. 9(e).
Namely, as shown in FIG. 10, the deadband circuit 223 is provided with input/output characteristics variable of the width by variation of the voltages V F1 and V F2 with taking the input/output voltage difference (V H -V FE ) of OV as a center according to a traverse signal and since a closed loop is formed as a whole of the traverse signal eliminating circuit for controlling the width of the deadband, temperature characteristics of the diodes 217 and 218 can be compensated. As a result, the input/output characteristics of the deadband circuit, in which the voltages V F1 and V F2 defining the deadband varies with the held voltage V H of the sample/hold circuit 216, can be obtained.
Since the voltages V F1 and V F2 have opposite polarities and the same magnitude of voltage difference relative to the held voltage V H , and the width of the deadband is variable depending upon the traverse signal level superimposing on the focus error signal so that the entire range of the traverse signal can be removed from the focus error signal, and influence of the traverse signal for the focus servo system can be successfully avoided.
In the practical construction, the gain of the focus control circuit is adjusted to be as great as possible in a range where oscillation of the focus servo circuit is avoided. The deadband circuit serves for preventing the focus servo from oscillating by adjusting the width of the deadband. This makes adjustment of gain of the focus control circuit easier and more simple.
It should be noted that though the shown embodiment employs resistors 221 and 222 having the same resistance as the resistors 251 and 261 of the current source means, it may possible to set the resistances of those resistors at mutually different values or to supply a different amplitude of current to the resistors 221 and 222 which may cause offset of the deadband with respect to the held voltage V H .
FIG. 13 shows a further embodiment of the traverse signal eliminating circuit in the optical disk recording and reproducing apparatus. The shown embodiment of the traverse signal eliminating circuit is generally represented by the reference numeral 300. The traverse signal eliminating circuit 300 has an amplifier 311 which is of a voltage follower type construction and receives the focus error signal St. The traverse signal eliminating circuit 300 also include a pair of peak and bottom hold circuits 318 and 319. The peak hold circuit 318 comprises a diode 312, a resistor 314 and a capacitor 316. On the other hand, the bottom hold circuit 319 comprises a diode 313, a resistor 315 and a capacitor 317. The outputs of the peak and bottom hold circuits 318 and 319 are connected to an adder circuit 322 including resistors 320 and 321. The diodes 312 and 313 are connected to a respective constant voltage source -Vcc and +Vcc via the resistors 314 and 315. With the voltages -Vcc and +Vcc supplied via the resistors 314 and 315, suitable forward current flow occurs through the diodes 312 and 313. The resistance of the resistors 320 and 321 are set at the same values.
The focus error signal St is applied to the diodes 312 and 313 of the peak and bottom hold circuit 318 and 319 via the voltage follower type amplifier 311. The peak value of the focus error signal St is rectified by the diode 312 and changes the capacitor 316. On the other hand, the bottom value of the focus error signal St is rectified by the diode 313 and charges the capacitor 317.
Assuming the time constant of the resistor 314 and capacitor 316, and the resistor 315 and capacitor 317 is T, and when this time constant T is sufficiently greater than the period of the traverse signal S M2 , the terminal voltages of the capacitors 316 and 317 varies as shown as the peak hold voltage e 1 and bottom hold voltage e 2 , as shown in FIG. 14(a). Since the peak hold voltage e 1 and the bottom hold voltage e 2 are applied through the resistors 320 and 321 of the same resistance, the voltage at the intersection point becomes (e 1 /2+e 2 /2) which becomes substantially equal to the pure focus error signal e f , as shown in FIG. 14(b). The output of the adder 322 is output through an operational amplifier 323.
As will be appreciated herefrom, it is necessary to set the resistance of the resistors 314 and 315 and the capacitors 316 and 317 to provide a sufficiently great time constant in relation to the period of the traverse signal.
FIG. 15 shows a modification of the foregoing embodiment of the traverse signal eliminating circuit of FIG. 13. In this modification, operational amplifiers 330 and 331 are added in the peak and bottom hold circuits 318 and 319. These operational amplifiers 330 and 331 are provided for improving non-linear characteristics of the diodes 312 and 313. For this purpose, the operational amplifiers 330 and 331 are disposed between the amplifier 311 and the diodes 312 and 313 of the peak and bottom hold circuits 318 and 319.
Furthermore, the shown modification employs a by-pass circuit by-passing the traverse signal eliminating circuit to directly feed the focus error signal to the phase compensation circuit. A switch 333 is disposed in the by-pass circuit for establishing and blocking the by-pass circuit. The position of the switch 333 is controlled by a gate signal of an OR gate 336. The OR gate is connected to one input terminal 334, to which a tracking ON state indicative signal is applied. The OR gate 336 is connected to the other input terminal 335, to which a focus search state indicative signal is applied. The OR gate 336 is responsive one of the tracking ON state indicative signal and the focus search state indicative signal to operate the switch 333 to the closed position for establishing the by-pass circuit.
As will be appreciated, a by-pass circuit with the switch 333 and the OR gate 336 to control the switch position between open and closed positions, will serve as a control circuit equivalent to that illustrated in FIG. 5, as the control circuit 125.
Therefore, in the embodiments of FIGS. 13 and 15, influence of the traverse signal can be successfully avoided by holding the peak and bottom values and obtaining average values thereof.
While the present invention has been disclosed in terms of the preferred embodiment in order to facilitate better understanding of the invention, it should be appreciated that the invention can be embodied in various ways without departing from the principle of the invention. Therefore, the invention should be understood to include all possible embodiments and modifications to the shown embodiments which can be embodied without departing from the principle of the invention set out in the appended claims. | An optical disk recording and reproducing appartus is provided with a signal processing circuit in a focus servo circuit for suppressing a traverse signal which has a frequency determined by the pitch of pre-grooves and the transversely shifting speed of a laser beam spot and which modulates a focus error signal during a search mode operation. This signal processing circuit successfully avoids an influence of the traverse signal focus servo system and thus assures accurate focus on the control. | 6 |
REFERENCE TO RELATED APPLICATIONS
This is a continuation-in-part patent application of a application Ser. No. 09/062,845, filed Apr. 20, 1998, entitled “Automatic Sub-floor Pumping System”, now U.S. Pat. No. 5,923,102.
FIELD OF THE INVENTION
The invention pertains to the field of methods and apparatus for removing water from under floors. More particularly, the invention pertains to basement pumping systems for preventing and alleviating water infiltration without the use of sumps, drain gutters, or other relatively large intrusions into the basement floor.
BACKGROUND OF THE INVENTION
Waterproofing and water elimination in basements is a subject of much attention because of the dismay caused by occasional water presence on basement floors. The present invention is the result of diligent and successful work in eliminating periods of water in the basement. In past years there would be surprise and alarm when finding water over the basement floor. Frantic effort would be required to undo the damage.
Conventionally a pump is placed in a well, pit or cavity (“sump”) cut into the floor in or below the gravel, rock or mud bed which is found under basement floors. Channel drains on the floor, drainpipes under the floor, or gutters around the base of the basement walls direct water to the sump. The sump pump, usually controlled by a float, pumps the water in the sump out of the basement through an outflow piped away from the house when the water exceeds a predetermined depth.
Sumps take away floor space—a common sump will measure several square feet—and are troublesome to install in existing basements. The conventional float control is prone to problems due to mechanical interference with the float mechanism, thus requiring clear space around the float, especially for a hinged float, which in turn increases the required sump size. Hoses or debris in the water can hold the float under water, preventing it from turning on the pump, or such objects can slip under the float, causing the pump motor to run continuously. Corrosion on the float hinge or slip rod can cause the float to hang up. In addition, the water level is not well controlled by float switches, and the process of floatation requires a certain amount of water to physically support the float sufficiently to activate a switch. In short, float switches are subject to jamming, require much space, and need wide water height variations.
If the basement floor is built on a mud, clay or compressed soil base, the under-floor drainage could be poor enough that even when the water level in the sump is kept low by the sump pump, water will still seep into the basement at other points. If possible, this water may need to be drained into the sump across the floor or through the channels or gutters. In some cases, the water will collect in low spots on the concrete floor during wet periods and cannot be removed at all except by evaporation and a dehumidifier.
Thus, in a conventional sump system, some quantity of water is nearly always present in the basement, either as unpumped water in the sump, or flowing down channels or gutters to the sump, or even as standing surface water in low spots. This increases the humidity in the basement and potentially damages any floor covering which might be present. The sump, gutters and/or collection drains are unsightly, as well.
SUMMARY OF THE INVENTION
In the present invention, the hydrostatic pressure, which builds up from gravity and forces water into the basement through the floor or lower walls, is relieved by sensing the water under the floor and pumping out the water to a drain or area away from the house. Thus, the water is prevented from ever entering the basement, and the basement remains dry.
In this situation, water pressure causes a flow along the interface between the concrete slab of the basement floor and the earth below. In fortunate cases where the slab is laid on a gravel or rock bed, the incoming water fills the void between rocks and tends to seek a uniform level as it accumulates up toward the floor, and a probe system with a single master probe at one location, as described and claimed in the parent application to this continuation-in-part, can serve an entire basement. If the basement floor is laid over packed earth, clay or mud, on the other hand, the water will tend to seep more slowly and unevenly, and more than one probe will be required.
The invention senses and removes water simply by means of tubes (which perform like large soda straws) and sensing wires (together, termed “probes”) inserted through one or more holes which are easily drilled in an existing basement floor, for example by using an impulse drill with a carbide tipped bit. Both the sensing of the water level and/or the pumping out of the sub-floor water are accomplished through these small holes drilled through the basement floor in trouble areas, eliminating the need for gutters, channels or sumps. A feature of the invention is that water may be extracted over large areas or along walls by use of multiple probes, arranged in several embodiments, with the use of a single water pump.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 shows the sub-floor pumping system of the invention in its simplest form, in a basement having a gravel underfloor bed, with a single probe.
FIG. 2 shows a detail of the master probe and cavity of the sub-floor pumping system of the invention, in a basement having a mud or clay underfloor bed.
FIG. 3 shows the sub-floor pumping system of the invention, in a basement having a mud or clay underfloor bed, with a master probe and a number of auxiliary probes.
FIG. 4 shows a detail of a first embodiment of an auxiliary probe, having a float-and-ball valve control.
FIG. 5 shows a detail of a second embodiment of an auxiliary probe, having a vacuum switch and solenoid valve control.
FIG. 6 shows a schematic of a vacuum switch control circuit, for use with the second embodiment of the invention, shown in FIG. 5 .
FIG. 7 shows a detail of a vacuum switch for use with the second embodiment of the invention, shown in FIG. 5 .
FIG. 8 shows a detail of a third embodiment of an auxiliary probe, having an electronic sensor and solenoid shut-off valve control.
FIG. 9 shows a schematic of a valve control circuit, for use with the third or fourth embodiments of the invention, as shown in FIGS. 8 and 11.
FIG. 10 shows a schematic of a sensor and pump control circuit which may be used with the invention.
FIG. 11 shows a fourth embodiment of the invention, in which all of the probes are “masters”.
FIG. 12 shows a schematic of a pump control circuit for use with the fourth embodiment of the invention, as shown in FIG. 11 .
DETAILED DESCRIPTION OF THE INVENTION
Ground water travels under the basement floor slab as clear water even though contacting clay or loam soil. The water flows under the floor at the concrete/clay interface because of hydrostatic pressure resulting from the weight of the water. Depending on wetness and soil condition, the water will accumulate and rise around the basement. Relieving the hydrostatic pressure, as accomplished by this invention, eliminates the intrusion in that area.
Referring to FIGS. 1 and 2, the master sensor/control system of the invention senses the water level in a sub-floor hole or cavity ( 31 ) in the gravel (FIG. 1, ( 21 )) or mud/clay (FIG. 2, ( 26 )) using a probe comprising sensor wires ( 29 )( 30 ), a suction tube ( 27 ), and optionally a strainer ( 22 ) and housing ( 20 ). The probe is inserted into the cavity ( 31 ) through a small (preferably about 1″ diameter) hole ( 58 ) drilled and prepared in the basement floor ( 25 ). A pump ( 17 ), powered by a pump motor ( 16 ) is connected by tubing ( 23 ) to the suction tube ( 27 ). A diaphragm pump, with appropriate strainer, has been found to be ideal, especially for FIG. 2 applications, although other kinds of pumps may be used within the teachings of the invention. Diaphragm pumps are self priming and quiet, but must be used with a strainer of 50 mesh or finer.
Sensor wires ( 29 )( 30 ), extending along the probe into the cavity ( 31 ) are connected to an electronic controller ( 1 ) which energizes the pump motor ( 16 ) when water needs to be removed. There are at least two sensor wires—an upper ( 30 ) activating wire, and a lower ( 29 ) holding wire. An optional lowest wire may have a tip which is at or below the level of the lower end of the suction tube ( 27 ), to act as a ground connection or, preferably, the controller ( 1 ) may be grounded electrically to an earth ground or the power system ground. The sensor wires ( 29 ) and ( 30 ) are preferably adhered to the suction tube ( 27 ) to hold them in place at the appropriate depth.
The controller ( 1 ) of the invention senses water on the sensor wires in the cavity ( 31 )—when the tip (FIG. 2 ( 33 )) of the top wire ( 30 ) is contacted by the rising electrically conductive water ( 34 ) in the cavity ( 31 ), the pump ( 17 ) turns on and water is pumped out through tube ( 27 ) until the level falls below the tip (FIG. 2 ( 35 )) of the lower holding wire ( 29 ). The pump then shuts off.
The controller and sensing wire arrangement of the invention may be like that disclosed in greater detail and claimed in co-pending parent application, Ser. No. 09/62,845, filed Apr. 20, 1998, and entitled “Automatic Sub-floor Pumping System”, which is incorporated here by reference. In all embodiments, the sensors are preferably negative with respect to ground water and thus by the phenomenon of “cathodic protection” corrosion of the sensors is minimized.
Alternatively, the invention may use a simpler controller circuit, as shown in FIG. 10 . The control circuit is made up of a pair of NPN transistors, emitter follower ( 101 ) and relay driver ( 102 ) driving a relay ( 100 ) coil. The relay is a double-pole relay, having two sets of normally open contacts ( 104 ) and ( 105 ). Preferably, a diode ( 103 ) is across the relay coil ( 100 ). A normally open pair of contacts ( 105 ) connects the AC source (VAC) to the pump. The upper (or “trigger”) sensor ( 107 ) is connected to the base of transistor ( 101 ), and the lower (holding) sensor ( 106 ) is also connected to the base of transistor ( 101 ), through normally open contacts ( 104 ). When water contacts the upper sensor, the current flow causes the emitter follower ( 101 ) and relay driver ( 102 ) transistor pair to activate the relay coil ( 100 ) and close contacts ( 104 ) and ( 105 ). The pump is activated, as VAC is connected to the pump output. Since the lower sensor ( 106 ) is now connected to the base of transistor ( 101 ) through contacts ( 104 ), the relay remains activated until the water has dropped below the lower sensor ( 106 ). At that point, relay ( 100 ) is deactivated, and contacts ( 104 ) and ( 105 ) are opened, shutting off the pump and disconnecting lower sensor ( 106 ) from the base of transistor ( 101 ). The controller will then wait until water once again rises to contact the upper sensor ( 107 ).
Preparation of Holes(s)
If the sub-floor ( 21 ) is a coarse gravel bed, as shown in FIG. 1, then a simple straight hole, drilled through the basement floor ( 25 ) and into the gravel bed ( 21 ) will suffice to lower the water level under the entire floor, which is termed the “basic embodiment”, below.
In many cases, however, the sub-floor material is not a porous gravel bed, but rather compacted earth, mud or clay, as shown in FIG. 2, ( 26 ). This material does not drain as does the gravel, and for optimum water removal operation a modest cavity ( 31 ) should be prepared under the hole ( 58 ) drilled through the floor slab. During a wet period, water accumulates in the cavity ( 31 ) as clear water from passages shown by ( 32 ).
The cavity ( 31 ) can be enlarged by using a rod or drill inserted through the hole ( 58 ) in the floor, digging and loosening the material in the subfloor, and scooping or washing away the loose material. In addition, it has been found useful to inject water under pressure into the holes, which can open flow channels ( 32 ) from a cavity ( 31 ) to the underground water source. This technique extends the effective range of a given probe and hole. While accomplishing this using a hand operated valve and a pressure gauge, the applied pressure can be seen to drop as a passage breaks through and the flow of water increases. After working in any hole with water, allow at least one half hour to clear before pumping.
Basic Embodiment
FIG. 1 shows the basic form of the invention, wherein a single suction tube ( 27 ), with associated sensor wires ( 29 ) and ( 30 ) work with controller ( 1 ) to pump out water from one cavity ( 31 ). The co-pending parent application to this application discusses this basic embodiment in greater detail, with emphasis on the controller circuitry.
Multiple Suction Points
Multiple suction probes can be used with one pump within the teachings of the invention, as shown in FIG. 3 . It will be understood that FIG. 3 is not to scale, and compresses the distance between the probes for illustrative purposes, and in actual use a number of holes and probes would be spread out over the area of the basement to be kept dry. Also, FIG. 3 shows four probes, while in actual use the number of probes would vary depending on the water problem and the configuration of the basement.
For basements built on a clay or earth base, multiple holes ( 58 ), ( 60 ), ( 61 ), ( 64 ) spaced approximately 12 feet apart, preferably along a wall, may be used to control water intrusion over an extended area. FIG. 3 shows such an arrangement with master probe ( 45 ) and auxiliary probes ( 59 )( 62 )( 63 ).
The master probe ( 45 ), preferably enclosed in sleeve ( 57 ) and screen ( 48 ), is connected to the pump ( 40 ) by tubing ( 44 ). Additional tubing ( 46 ) connects the master probe ( 45 ) to the various auxiliary probes ( 59 )( 62 )( 63 ), either using a “T” fitting at each probe, as shown in FIG. 3, with a cap ( 65 ) at the end of the “daisy chain”, or by a “hub and spoke” arrangement with separate lines running from each probe to a central point, or some variant on these. Each auxiliary probe ( 59 )( 62 )( 63 ) is inserted through its own small hole (( 60 )( 61 )( 64 ), respectively) in the floor into its own cavity (( 51 )( 53 )( 55 )). The cavities are prepared as described above.
As discussed above, the main probe ( 445 ) has sensing electrodes ( 49 ), connected through cable ( 49 ) to the controller ( 1 ) to turn the pump on when the water level ( 50 ) in the main cavity ( 47 ) reaches an upper activating electrode, and off when the level drops below a lower holding electrode.
The primary or master probe with electronic pump control sensing should be placed in a location where the water is most prevalent—in the cavity where water first appears after a rain. The pump will operate and will drain the master cavity, and the auxiliary cavities will thus be drained before the water level in any of the other cavities rises high enough to leak into the basement.
If a simple suction tube is used for an auxiliary probe, as soon as the probe drains its cavity it will begin to draw air into the probe, and hence into the tubing. This air will be drawn into the pump, and it will not be able to draw water from the master probe or from the auxiliary probes which are still submerged. Thus, the auxiliary probes should be equipped with some method of shutting them off when there is no water to pump from their associated hole.
Probe Design
Experience dictates that probes shown in FIG. 2 should be formed with a right-angle bend at the floor level to permit a low profile (preferably of less than an inch above the floor) for the tubing and wires. For mud-based holes as shown in FIG. 2, suction tube ( 23 ) can be ¼″ I.D. plastic tubes with sensor wires. For rock-based holes as shown in FIG. 1, the suction tube ( 23 ) can be a ½″ I.D. plastic tube for a greater flow.
In another useful feature, the upper sensor wire ( 30 ) can be exposed at one point ( 28 ), to permit testing by touching the exposed wire with a moist finger. This can be done by stripping back the insulation at one point, or by adding a short tinned wire which emerges from the plastic jacket around the wire. Tests can thus be made without the necessity of removing a probe from its hole.
Embodiments Using Auxiliary Probes(s)
The auxiliary probes should thus shut off, at the latest, when their cavity is pumped down below the intake end of the probe, and then re-open to draw water when water is present. This can be done by a number of different methods, such as the embodiments described in more detail below.
An important factor in these embodiments is that the auxiliary probe mechanisms do not, in all but embodiment 4 , control the pump—they only serve to shut off the auxiliary probes when insufficient water is present to avoid drawing air into the connecting tubing.
Embodiment 1
Auxiliary Probe with Ball Valve and Float
FIG. 4 shows a detail of the lower end of an auxiliary probe incorporating the float and ball valve embodiment of the invention to automatically close off the auxiliary probe before the water level drops below the probe intake. This method is simple, requires no power or active components, and performs adequately, especially if the number of probes is limited to one or two. Many basement situations require no more than this, and indeed some basements require no auxiliary probes. (Basement floors which are wisely built on a rock bed several inches in depth require only one extraction probe to eliminate the water trouble over a total floor area.)
Referring to FIG. 4, the pickup tube ( 70 ) of the auxiliary probe is extended horizontally by a chamber ( 68 ) which has a closed lower surface ( 69 ) and an upper surface ( 71 ) with a pair of holes, one ( 72 ) communicating with the pickup tube ( 70 ), and the other ( 73 ) forming a seat for a ball ( 76 ) or other closure member (for example, a conical closure member could be used, with the smaller end extending through the hole). The ball ( 76 ) is attached to a float ( 79 ) by a rod ( 77 ), and a guide ( 72 ) is provided to keep the float ( 79 ) and ball ( 76 ) in position over the valve hole ( 73 ). The float may be a hollow plastic ball, flattened to fit, or made of foam plastic or cork, or other material as might be desired.
When the water level rises above a preselected depth, the float ( 79 ) raises the ball ( 76 ) off its seat to an open position ( 78 ), and water may be drawn through port hole ( 73 ). When the pump starts and draws off water through the hole ( 73 ) into the pickup tube ( 70 ), the water level drops until the ball ( 76 ) once again closes off the valve hole ( 73 ). This blocks further flow into the pickup tube, preventing the water level from being drawn so low as to allow air to be drawn into the system.
A relief hole ( 75 ) is preferably provided through the chamber wall ( 74 ) into the lower chamber ( 68 ). The relief hole ( 75 ) (which may be as small as 0.040″) prevents the ball ( 76 ) from being held into the valve hole ( 73 ) by low pressure in the chamber ( 68 ), which would prevent the float ( 79 ) from lifting the ball ( 76 ) from the seat.
Embodiment 2
Auxiliary Probe with Vacuum Switch and Solenoid Valve
FIG. 5 shows an embodiment of the invention in which the flow through the auxiliary probes is electrically controlled by a solenoid valve ( 84 ) operated by a valve controller ( 85 ) connected to or incorporating a vacuum pressure switch ( 82 ), with its pressure sensing input ( 83 ) in the line ( 81 ) between the auxiliary pickup tube ( 80 ) and normally closed shutoff valve ( 84 ). The valve ( 84 ), in turn, is connected by tubing ( 87 ) to the intake line or master probe ( 45 ), as shown in FIG. 5, or to the central pickup connection or auxiliary pickup daisy chain, as described above.
The valve controller ( 85 ) is connected by wires ( 86 ) to the pump controller ( 1 ), so that electrical power is applied to the controller ( 85 ), and thus the switch ( 82 ) when the pump ( 40 ) is actuated. The actual voltage supplied by the pump controller ( 1 ) would depend on the requirements of the particular valve ( 84 ) chosen, but it should be noted that a low-voltage valve would be preferred, so that low-voltage wiring ( 86 ) could be used. An Aquatec model E-50 solenoid-operated valve, manufactured by Aquatec Water Systems, Inc., 17422 Pullman St., Irvine, Calif. 926149, can be used, but other types and models of valve would also be applicable.
The pressure switch ( 82 ) is a normally open switch, which closes when there is vacuum (i.e. lower than ambient pressure) at the sensing input ( 83 ) and is open when the pressure at the sensing input ( 83 ) is at or above ambient. When the switch is closed, electrical power is applied to the solenoid of the valve ( 84 ), causing it to open and permit flow of water through the line ( 87 ).
FIG. 7 shows a solid state vacuum switch which may be used with this embodiment of the invention. The sensing input ( 83 ) is connected to a chamber ( 132 ) having a resilient side forming a diaphragm ( 133 ). The diaphragm ( 133 ) is made of thin rubber or plastic, and has a vane ( 130 ) centrally located, so that when there is a vacuum present at the sensing input ( 83 ), the resilient diaphragm ( 133 ) is drawn inward to a deflected position ( 134 ).
The vane ( 130 ) fits in the slot of an optical interrupter ( 126 ). A model H21B1 optical interrupter, made by QT Optoelectronics, Inc., 610 N. Mary Ave., Sunnyvale, Calif. 94086-2906, would be an acceptable device, although there are many others from QT or other manufacturers. The optical interrupter has an infrared LED ( 128 ) which emits a beam of light ( 138 ) through a gap ( 135 ) onto a phototransistor ( 127 ). Normally, the vane ( 130 ) blocks this beam ( 138 ), and the switch is “open”. When the diaphragm ( 133 ) is drawn upward by vacuum ( 134 ), vane ( 130 ) is drawn out of the way of the beam ( 138 ), permitting the light to fall on the phototransistor ( 127 ), causing it to conduct or “close the contacts” of the switch. Although this design of switch is desirable, as it has no mechanical parts, other vacuum switches, commercially available, could be used within the teachings of the invention.
In operation, when the pump ( 40 ) is running and the water level ( 90 ) is above the end of the pickup tube ( 80 ) in cavity ( 89 ), there is a lower than ambient pressure (“vacuum”) present at the sensing input ( 83 ) of switch ( 82 ). The switch contacts are thus closed, causing electrical power to flow from the controller ( 1 ) through wires ( 86 ) and switch ( 82 ) to the actuating input of valve ( 84 ), opening the valve and allowing the water to flow from the auxiliary probe. If the water level ( 90 ) drops below the pickup tube, so that air is sucked into the tube ( 80 ) and line ( 81 ), the vacuum switch ( 82 ) opens to de-energize the normally closed valve ( 84 ). This prevents air from being drawn into line ( 87 ), and permits all other probes to draw water.
It should be noted that when the pump ( 40 ) is not in operation or valve ( 84 ) is closed, the pressure at the sensing input ( 83 ) of the switch ( 82 ) would be at ambient (i.e. “no vacuum”), and the switch ( 82 ) would thus be open. With the switch ( 82 ) open, no power is applied to the valve ( 84 ), and the valve remains in its closed position. When the pump ( 40 ) is turned on by the controller ( 1 ), power appears on wires ( 86 ), but because the valve ( 84 ) is closed and the sensing input ( 83 ) is at ambient pressure, the open switch ( 82 ) would prevent the valve ( 84 ) from being opened, if a delay was not provided.
FIG. 6 shows a valve controller circuit (( 85 ) in FIG. 5) which provides a delay when the power is applied, permitting time for the pump to start and develop vacuum before giving effect to the vacuum switch ( 82 ). The output of the optical interrupter ( 126 ) phototransistor ( 127 ) is connected to the base of a relay driver transistor ( 123 ). Thus, when the vane ( 130 ) is lifted out of the gap, and the light from LED ( 128 ) shines on phototransistor ( 127 ), relay driver ( 123 ) is turned on, and activates relay coil ( 121 ). This, in turn, closes contacts ( 124 ), connecting the AC current (VAC) to the valve connector ( 120 ) (it is assumed here that the valve, as the one specified above, is an AC solenoid, but it will be understood that the relay closure could switch any form of current as might be needed by a specific valve type).
Capacitor ( 125 ) provides a delay function, effectively shunting the vacuum switch photo interrupter ( 126 ). When the power (V+) is applied by the activation of the pump, capacitor ( 125 ) holds the base of transistor ( 123 ) positive as it charges, causing the relay ( 121 ) to pull in and opening the valve. The pump begins to draw from the probe, either air (no vacuum) or water (vacuum). Once the capacitor is charged, if there is no vacuum present, then the vane ( 130 ) will be blocking the light from LED ( 128 ) onto phototransistor ( 127 ), and the base of transistor ( 123 ) will go low, and turn off the relay ( 121 ), closing the valve. On the other hand, if there is vacuum (i.e. the probe is drawing water), then the phototransistor ( 127 ) will be receiving light and will hold the base of transistor ( 123 ) high until the vacuum is gone and the vane drops back to obstruct the light beam and thus close the shut-off valve. The value of capacitor ( 125 ) may be chosen to give any delay desired, using conventional circuit design techniques. A delay of approximately 2 seconds has been found to be appropriate, requiring a capacitor ( 125 ) of approximately 47 μf in the circuit shown in FIG. 6 .
If desired, this embodiment of the auxiliary probe could be set up with a vacuum sensor and valve connected to more than one probe, within the teachings of the invention. There could be a single sensor/valve/controller for all of the auxiliary probes, or a number of sensor/valve/controllers, each with one or more associated probes. In such a setup, two or more probes are connected to a central point, or “daisy chained” together, and the central point or chain is connected to a single vacuum sensor and, through the valve, to a suction line. When any of the probes ran dry, the vacuum sensor would close the valve and shut off the suction from all the probes in the group.
Embodiment 3
Auxiliary Probe(s) with Solenoid Valve(s) and Electronic Sensor(s)
FIG. 8 shows an embodiment of the invention in which the auxiliary probe ( 80 ) is fitted with one or two sensor wires ( 93 ) having sensing tip(s) ( 94 ) located in the auxiliary cavity ( 89 ) in the sub-floor.
The sensor wire(s) ( 93 ) are connected to a sensor controller ( 91 ), which may work like the master controller ( 1 ) described in detail in co-pending parent application Ser. No. 09/62,845, incorporated here by reference, or in a simpler form similar to the sensor/pump control discussed above. A schematic of a circuit usable as valve controller ( 91 ) is shown in detail in FIG. 9 .
The power cable, either from the pump controller or from a separate power supply, is connected to the controller via a connector ( 111 ). The power is preferably supplied in the form of low-voltage AC, so that lighter wire may be used within the requirements of the electrical code. The lower ( 106 ) and upper ( 107 ) sensor wires are connected via another connector ( 110 ), and a third connector ( 109 ) receives the wires from the valve ( 90 ). The negative DC voltage (V−) required to power the electronics in the controller is derived from the AC by a diode ( 113 ) and electrolytic capacitor ( 114 ).
The control circuit is made up of a pair of transistors, emitter follower ( 101 ) and relay driver ( 102 ) driving a relay ( 100 ) coil. The relay is a double-pole relay, having two sets of normally open contacts ( 104 ) and ( 105 ). Preferably, a diode ( 103 ) is across the relay coil ( 100 ). A normally open pair of contacts ( 105 ) connects the AC source (VAC) to the valve. The upper (trigger) sensor ( 107 ) is connected to the base of transistor ( 101 ), and the lower (holding) sensor ( 106 ) is also connected to the base of transistor ( 101 ), through normally open contacts ( 104 ). When water contacts the upper sensor, the current flow causes the emitter follower ( 101 ) and relay driver ( 102 ) transistor pair to activate the relay coil ( 100 ) and close contacts ( 104 ) and ( 105 ). The valve is opened, as AC voltage (VAC) is applied to the valve connector ( 109 ). Since the lower sensor ( 106 ) is now connected to the base of transistor ( 101 ) through contacts ( 104 ), the relay remains activated until the water has dropped below the lower sensor ( 106 ). At that point, relay ( 100 ) is deactivated, and contacts ( 104 ) and ( 105 ) are opened, removing energizing voltage from the valve, and disconnecting lower sensor ( 106 ) from the base of transistor ( 101 ). The controller will then wait until water once again rises to contact the upper sensor ( 107 ).
Alternatively, the sensor controller could be a simple conductivity detector, detecting conductivity between a single wire and ground when the wire is submerged in water. If one sensor wire is used, as explained in the parent application to this continuation-in-part, the valve would tend to cycle rapidly as the water level drops close to the bottom of the sensor wire. A capacitor could be used in the circuit to give a hysteresis action, and minimize the rapid-cycling effect of using a single wire.
Embodiment 4
All Probes are Master Probes
FIG. 11 shows a diagram of another embodiment of the invention, a variation of embodiment 3 in which each of the probes is a “master”. The controller circuit ( 140 ) of FIG. 9 is used at each of the probes ( 148 ), each of which is equipped with two sensors ( 149 ) connected via wires ( 146 ) to the controller ( 140 ). The controllers ( 140 ) control valves ( 143 ) at each probe via wires ( 144 ). All of the probe controllers ( 140 ) are powered via power bus wires ( 141 ), and all of the valves are connected to a common suction line ( 147 ) by “T” connectors ( 145 ) or to a central hub, or by connection of tubing from each valve to a multiport manifold at the pump ( 40 ). In this embodiment, the pump controller ( 142 ) senses current flow on the power bus ( 141 ), turning on the pump ( 40 ) when it senses that a valve controller ( 140 ) has energized open one of the valves ( 143 ) in response to the detection of water on a sensor ( 149 ). Thus, all of the probes are “masters”, in that the pump is turned on by the presence of water in any cavity, not just in the “master” cavity as described in the other embodiments.
FIG. 12 shows a schematic of a pump controller (( 142 ) in FIG. 11) for use with the embodiment of FIG. 11. A transformer ( 160 ) steps down the line voltage ( 161 ) to a lower AC voltage ( 162 ) at the secondary, to power the valve controllers (( 140 ) FIG. 11, and the schematic of FIG. 9) through connector ( 172 ) and the pump through connector ( 171 ). Although 24 VAC has been shown in this schematic, it will be understood that with appropriate selection of components, other voltages may be used as well. A diode ( 165 ) and electrolytic capacitor ( 175 ) rectify the AC supply into DC to power the controller's electronics. A sensing resistor ( 174 ) in one of the lines to the valve controllers ( 172 ) develops a voltage when current flows through the line. A value of 10 ohms has been found to be effective for sensing resistor ( 174 ), although other values can be used depending on circuit requirements. Back-to-back diodes ( 173 ) limit this voltage drop to about 1.4 Volts, and the voltage is converted to DC by diode ( 169 ), smoothed by electrolytic capacitor ( 170 ), and applied to the base of PNP transistor ( 167 ). When the negative voltage is applied, transistor ( 167 ) conducts and activates the coil ( 166 ) of a relay, closing normally open contacts ( 168 ) and applying activating power to the pump connector ( 171 ). Thus, if water is sensed at any cavity, its associated valve is opened, and the current drawn by the valve turns on the pump.
Accordingly, it is to be understood that the embodiments of the invention herein described are merely illustrative of the application of the principles of the invention. Reference herein to details of the illustrated embodiments are not intended to limit the scope of the claims, which themselves recite those features regarded as essential to the invention. | Hydrostatic pressure, which builds up from gravity and forces water into a basement through the floor or lower walls, is relieved by sensing the water under the floor and pumping out the water to a drain or area away from the house. Thus, the water is prevented from ever entering the basement, and the basement remains dry. The invention senses and removes water simply by means of tubing and sensing wires inserted through one or more small holes which are easily drilled in an existing basement floor, for example by using an impulse drill with a carbide tipped bit. Both the sensing of the water level and the pumping out of the sub-floor water are accomplished through these small holes drilled through the basement floor in trouble areas, eliminating the need for gutters, channels or sumps. | 6 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to gratings, and in particular to a quick-release grating.
2. Background of the Invention
In today's security-conscious world, gratings have become a common architectural feature in residences and commercial buildings alike. The incidence of burglaries, home invasions and thefts which has occurred in this century has contributed to a desire for protection against unwanted building entries. As a result, many windows feature sturdy gratings made of metal bars welded into a frame, which cover a window or other building aperture, and prevent entry by a burglar, who could otherwise gain entrance merely by breaking the window glass.
An unfortunate side effect of the existence of window gratings is their converse ability to prevent building occupants from exiting through the barred window in an emergency, such as a building fire. It is a sad irony that every year individuals are trapped inside burning buildings by the very window gratings which were supposed to protect them.
Thus it has become extremely important to provide a grating quick-release which on the one hand is secure enough to prevent burglaries, yet on the other hand is capable of quick, reliable release. In this fashion, building occupants would be provided an escape route through building apertures equipped with a grating quick-release, and yet when the apertures they cover are not being used as exits, the gratings would prevent unwanted entry by burglars and thieves.
Existing Designs
A number of devices capable of releasing a grating have been proposed. U.S. Pat. Nos. 3,913,957, 4,243,090 and 5,657,578 were granted Astie et al., Kemp, and Thompson respectively. While these devices provided a means of releasing a security grating, it was possible for a burglar to break the window glass and introduce a hand or tool through the grating and open the grating. Needless to say, this design shortcoming defeated the very purpose for installing a security grating in the first place.
U.S. Pat. Nos. 4,476,957 and 5,603,183 were granted Ory and Giovinazzi respectively. These devices combined a ladder function with a security grating, and appear to have been designed for a second floor (or higher) window. Although means to release the grating was taught, the release mechanism in both cases required substantial vertical clearance below the window upon which the grating was mounted. Where such substantial vertical clearance did not exist, it would be difficult or impossible to open the grating in case of fire.
SUMMARY OF THE INVENTION
Accordingly, it is an object of the present invention to provide a quick-release grating which is easily unlocked with a single pull of a handle. Design features allowing this object to be accomplished include an actuator bar attached to deadbolts by means of cable and pulleys. Advantages associated with the accomplishment of this object include the ability to quickly and easily unlock a security grating in case of fire, and then to use the opening it covered to exit the structure.
It is another object of the present invention to provide a quick-release grating which provides a means to keep the opened grating from re-closing. Design features allowing this object to be accomplished include a safety pin disposed within a safety pin housing, and a safety pin spring which is pre-loaded in order to urge the safety pin into an extended position. A benefit associated with the accomplishment of this object is prevention of re-closing of the grating after it has been opened, thus maintaining open an escape route for other building occupants.
It is still another object of this invention to provide a quick-release grating which prevents burglars from accessing the actuator bar from the exterior of the building. Design features enabling the accomplishment of this object include a lockable box door, and an actuator disposed within the box. An advantage associated with the realization of this object is increased security from break-ins.
It is another object of the present invention to provide a quick-release grating which may be remotely activated from an interior location removed from the grating itself. Design features allowing this object to be accomplished include a remote actuator connected to remote deadbolt assemblies by means of cables. A benefit associated with the accomplishment of this object is obviation of the need to enclose the actuator within a locked box, and hence speedier quick-release grating unlocking.
It is still another object of this invention to provide a quick-release grating which may be used to unlock an exterior grating from the inside of a structure to which it is mounted. Design features enabling the accomplishment of this object include a transwall actuator featuring one or more deadbolts exterior to the building, connected to an interior remote actuator by means of cables carried on pulleys. Advantages associated with the realization of this object include the provision of a fire escape route actuatable from the inside of a building even when the grating is mounted external to the building, as well as elimination of the need to enclose the actuator in a locked box, thus providing faster grating unlocking.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention, together with the other objects, features, aspects and advantages thereof will be more clearly understood from the following in conjunction with the accompanying drawings.
Seven sheets of drawings are provided. Sheet one contains FIG. 1 . Sheet two contains FIG. 2 . Sheet three contains FIG. 3 . Sheet four contains FIG. 4 . Sheet five contains FIG. 5 . Sheet six contains FIG. 6 . Sheet seven contains FIG. 7 .
FIG. 1 is a front isometric view of an actuator.
FIG. 2 is a front view of a quick-release grating.
FIG. 3 is a front isometric view of an U-handle actuator.
FIG. 4 is a front isometric cross-sectional view of a safety pin.
FIG. 5 is a front isometric cross-sectional view of a remote actuator connected to remote deadbolt assemblies by means of cables, and a safety pin.
FIG. 6 is a front cross-sectional view of an grating-mounted remote actuator with spring-loaded deadbolts installed on a grating top member and a grating bottom member.
FIG. 7 is a side cross-sectional view of a transwall actuator.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The instant disclosure teaches a number of embodiments of the instant invention. FIG. 1 is a front isometric view of actuator 2 . FIG. 2 depicts same installed on grating 40 . FIG. 3 is a front isometric cross-sectional view of an alternate embodiment actuator 2 . FIG. 4 is a front isometric cross-sectional view of safety pin 56 , which keeps grating 40 from slamming shut and re-locking once it has been opened using the instant quick-release method.
FIG. 5 is a front isometric cross-sectional view of remote actuator 78 connected to remote deadbolt assemblies 74 by means of cables 20 , installed on frame 36 and grating 40 , and safety pin 56 .
FIG. 6 is a front cross-sectional view of an alternate embodiment remote actuator 78 with spring-loaded deadbolts 22 installed on grating top member 45 and grating bottom member 47 . FIG. 7 is a side cross-sectional view of transwall actuator 10 , whereby an interior remote actuator 78 may be employed to actuate externally mounted deadbolt(s) 22 .
Referring now to FIGS. 1 and 2, we observe actuator 2 mounted in grating 40 , which in turn is mounted within frame 36 . Frame 36 would be mounted over an existing edifice aperture such as a window, door, etc.
Frame 36 comprises frame aperture 38 sized to admit grating 40 . Grating 40 is disposed within frame aperture 38 , and is rotatably attached to frame 36 by means of grating hinges 44 . When grating 40 is closed, it is disposed substantially co-planar with frame 36 . Grating 40 may be opened relative to frame 36 by rotating grating 40 on hinges 44 so that grating 40 opens in the same manner as a conventional vertically-pivoted window.
Grating 40 comprises grating top member 45 rigidly attached to grating bottom member 47 by means of grating side members 43 . A matrix of bars 42 are disposed within, and rigidly attached to, grating top member 45 , grating bottom member 47 , and grating side members 43 . Grating bars 42 prevent unwanted entry through the edifice aperture to which frame 36 and grating 40 are attached.
Actuator 2 is mounted on a grating side member 43 opposite grating hinges 44 . Actuator 2 comprises actuator bar 11 attached to deadbolts 22 by means of cables 20 carried on pulleys 18 . Actuator bar 11 pivots on handle axle 14 , and comprises handle 12 on one side of handle axle 14 and lever 16 on the other side of handle axle 14 . Cables 20 are attached to an extreme (end) of lever 16 opposite handle 12 . The action of pulling on handle 12 has the effect of pivoting actuator bar 11 on handle axle 14 as indicated by arrow 15 , which in turn pulls cables 20 as indicated by arrows 17 , which causes deadbolts 22 to retract as indicated by arrows 19 . As may be observed in FIG. 2, when grating 40 is closed and locked in frame 36 , deadbolts 22 extend through grating bores 41 and frame bores 37 . When handle 12 is pulled, cables 20 retract deadbolts 22 out of frame bores 37 , and permit grating 40 to open. Each cable of actuator 2 rides on two pulleys 18 : one pulley 18 whose pulley axis of rotation 21 is parallel to handle axle 14 , and one pulley 18 whose pulley axis of rotation 21 is perpendicular to handle axle 14 .
Actuator 2 further comprises box 32 having box bores 34 , and deadbolt spring stops 28 having deadbolt spring stop bores 30 . See also FIG. 6 . Box bore 34 and deadbolt spring stop bore 30 are sized to slidably admit deadbolt 22 . Deadbolts 22 are spring-loaded in the extended position depicted in FIG. 1 by means of deadbolt springs 24 . Deadbolt spring 24 is constrained in a compressed position between deadbolt spring stop 28 and E-clip 26 , which is installed on deadbolt 22 . E-clip 26 is a standard, off-the-shelf fastener which is made of stiffly resilient material. When a properly sized E-clip 26 is installed on deadbolt 22 , it will retain its axial position on deadbolt 22 , even under the urging of deadbolt spring 24 . Thus, compressed deadbolt spring 24 pushes against deadbolt spring stop 28 and E-clip 26 , thereby spring-loading deadbolt 22 into the extended position depicted in FIGS. 1, 3 , 5 , 6 and 7 .
FIG. 2 depicts actuator 2 installed in grating 40 . Box 32 comprises box door 46 hingedly attached to box 32 by means of box door hinges 50 . Box door 46 also comprises a means of locking box door 46 relative to box 32 , in order to prevent unauthorized operation of actuator 2 . The embodiment illustrated in FIG. 2 depicts box door lock 48 which is locked and unlocked by means of a conventional key. Other box door lock 48 embodiments contemplated to be within the scope of the instant invention include a keypad type electronic lock, the use of a magnetic card type lock such as is common in hotels and motels, a combination lock, a voice activated lock, a fingerprint reader lock, an eye retinal scanner recognition lock, and any other appropriate locking mechanism.
FIG. 3 depicts U-handle actuator 4 comprising U-handle 52 . U-handle 52 comprises U-handle cross bar 53 . A U-handle leg 54 is attached to each extreme of U-handle cross bar 53 . Each U-handle leg 54 rotates about a handle axle 14 . One cable 20 is attached to each U-handle leg 54 at an extreme opposite U-handle cross bar 53 . The action of pulling on U-handle cross bar 53 has the effect of pivoting U-handle legs 54 on handle axles 14 as indicated by arrow 55 , which in turn pulls cables 20 as indicated by arrows 57 , which causes deadbolts 22 to retract as indicated by arrows 59 . Each cable 20 of alternate embodiment actuator 2 rides on two pulleys 18 whose pulley axes of rotation 21 are perpendicular to handle axle 14 .
As may be observed in FIGS. 2 and 4, safety pin 56 is mounted to frame 36 , and is spring-loaded into an extended position, such that when grating 40 is opened, safety pin 56 extends and prevents grating 40 from re-closing. Safety pin 56 is slidably disposed within safety pin housing bore 60 of safety pin housing 58 . Safety pin spring 66 is installed in a compressed position within safety pin housing bore 60 between safety pin 56 and safety pin spring stop 68 . Safety pin spring stop 68 is immobilized relative to safety pin housing 58 by means of lock pin 70 , which extends through safety pin housing 58 into safety pin spring stop 68 . Guide pin 64 is rigidly attached to safety pin 56 , and extends radially from safety pin 56 . Safety pin housing 58 further comprises safety pin housing slot 62 , sized to slidably admit guide pin 64 . Guide pin 64 reciprocates within safety pin housing slot 62 , and limits the movement of safety pin 56 to reciprocation within safety pin housing bore 60 .
Safety pin 56 is depicted in FIG. 4 in the retracted position, as it would be constrained by grating 40 when grating 40 is closed. When grating 40 is opened, grating 40 slides off of spring-loaded safety pin 56 , permitting safety pin spring 66 to force safety pin 56 into its extended position, as indicated by arrow 72 . When extended, safety pin 56 extends into the path of travel of grating 40 , thus preventing it from rotating into the closed position.
FIG. 5 is a front isometric cross-sectional view of remote actuator 78 connected to remote deadbolt assemblies 74 by means of cables 20 , installed on frame 36 and grating 40 , and safety pin 56 . A major benefit of this configuration is obviation of the need to enclose remote actuator 78 within a locked box 32 , and hence speedier quick-release grating unlocking.
Remote actuator 78 comprises actuator bar 11 which pivots on handle axle 14 , and comprises handle 12 on one side of handle axle 14 , and lever 16 on the other side of handle axle 14 . Cables 20 are attached to an extreme of lever 16 opposite handle 12 . The action of pulling on handle 12 has the effect of pivoting actuator bar 11 on handle axle 14 as indicated by arrow 15 , which in turn pulls cables 20 as indicated by arrows 17 , which causes deadbolts 22 to retract. When grating 40 is closed and locked in frame 36 as depicted in FIG. 5, deadbolts 22 extend through grating bores 41 and frame bores 37 . When handle 12 is pulled, cables 20 retract deadbolts 22 out of grating bores 41 , and permit grating 40 to open. Each cable of remote actuator 78 rides on two pulleys 18 : one whose pulley axis of rotation 21 is parallel to handle axle 14 , and one pulley 18 whose pulley axis of rotation 21 is perpendicular to handle axle 14 .
Actuator bar 11 is attached to deadbolts 22 by means of cables 20 carried on pulleys 18 . Deadbolts 22 comprise part of remote deadbolt assemblies 74 . Each remote deadbolt assembly 74 comprises remote deadbolt housing 75 having remote deadbolt housing bore 77 sized to slidably admit deadbolt 22 . Deadbolt stop 76 and annular deadbolt spring stop 29 are disposed at opposite extremes of remote deadbolt housing 75 . Deadbolt stop 76 is immobilized relative to remote deadbolt housing by means of lock pin 70 extending through remote deadbolt housing 75 into deadbolt stop 76 . Annular deadbolt spring stop 29 is immobilized relative to remote deadbolt housing 75 by means of lock pin 70 extending through remote deadbolt housing 75 into annular deadbolt spring stop 29 .
Deadbolts 22 are spring-loaded in the extended position depicted in FIG. 5 by means of deadbolt springs 24 . Deadbolt spring 24 is constrained in a compressed position between deadbolt spring stop 28 and E-clip 26 , which is installed on deadbolt 22 . E-clip 26 is a standard, off-the-shelf fastener which is made of stiffly resilient material. When a properly sized E-clip 26 is installed on deadbolt 22 , it will retain its axial position on deadbolt 22 , even under the urging of deadbolt spring 24 . Thus, compressed deadbolt spring 24 pushes against deadbolt spring stop 28 and E-clip 26 , thereby spring-loading deadbolt 22 into the extended position.
In operation, handle 12 is pulled, which pulls cables 20 , which in turn retract deadbolts 22 . Grating 40 may then be opened, and safety pin 56 prevents unwanted re-closing of same.
FIG. 6 is a front cross-sectional view of an grating-mounted remote actuator 79 with spring-loaded deadbolts 22 installed on grating top member 45 and grating bottom member 47 .
The grating-mounted remote actuator 79 depicted in FIG. 6 comprises actuator bar 11 which pivots on handle axle 14 , and comprises handle 12 on one side of handle axle 14 and lever 16 on the other side of handle axle 14 . Cables 20 are attached to an extreme of lever 16 opposite handle 12 . As in the previous embodiments, the action of pulling on handle 12 has the effect of pivoting actuator bar 11 on handle axle 14 , which in turn pulls cables 20 , which causes deadbolts 22 to retract. When grating 40 is closed and locked in frame 36 , deadbolts 22 extend through grating bores 41 and frame bores 37 . When handle 12 is pulled, cables 20 retract deadbolts 22 out of frame bores 37 , and permit grating 40 to open. Each cable of the grating-mounted remote actuator 79 rides on one pulley 18 whose pulley axis of rotation 21 is parallel to handle axle 14 .
Actuator bar 11 is attached to deadbolts 22 by means of cables 20 carried on pulleys 18 . Deadbolts 22 are spring-loaded in the extended position depicted in FIG. 6 by means of deadbolt springs 24 . Deadbolt spring 24 is constrained in a compressed position between deadbolt spring stop 28 and E-clip 26 , which is installed on deadbolt 22 . The entirety of grating-mounted remote actuator 79 and deadbolt 22 assemblies, except for the protruding extremes of deadbolts 22 which engage frame bores 37 , may be locked within box 32 as is depicted in FIG. 6, to prevent unauthorized operation.
In operation, handle 12 is pulled, which pulls cables 20 , which in turn retract deadbolts 22 . Grating 40 may then be opened, and safety pin 56 prevents unwanted re-closing of same.
FIG. 7 is a side cross-sectional view of transwall actuator 10 , whereby an interior remote actuator 78 (not depicted in FIG. 7, but one embodiment thereof is depicted in FIG. 5) may be employed to actuate externally mounted deadbolts 22 . Major benefits of the quick-release grating embodiment depicted in FIG. 7 include the provision of a fire escape route actuatable from the inside of a building even when grating 40 is mounted external to the building, as well as elimination of the need to enclose remote actuator 78 in a locked box 32 , thus providing faster grating 40 unlocking.
Transwall actuator 10 comprises exterior housing 84 connected to interior housing 82 by means of pipe 80 , and another pipe 80 connects interior housing 82 to remote actuator 78 . Exterior housing 84 is mounted to the outside of wall 86 ; interior housing 82 is mounted to the inside of wall 86 . Interior housing 82 comprises pulley 18 which carries cable 20 . Exterior housing 84 comprises pulley 18 which carries cable 20 . Exterior housing 84 further comprises deadbolt 22 , which is spring-loaded in the extended position depicted in FIG. 7 by means of deadbolt spring 24 . Deadbolt spring 24 is constrained in a compressed position between deadbolt spring stop 28 and E-clip 26 , which is installed on deadbolt 22 . Deadbolt stop 76 prevents over-extension of deadbolt 22 . E-clip 26 is a standard, off-the-shelf fastener which is made of stiffly resilient material. When a properly sized E-clip 26 is installed on deadbolt 22 , it will retain its axial position on deadbolt 22 , even under the urging of deadbolt spring 24 . Thus, compressed deadbolt spring 24 pushes against deadbolt spring stop 28 and E-clip 26 , thereby spring-loading deadbolt 22 into the extended position.
In operation, handle 12 in remote actuator 78 is pulled, which pulls cable 20 carried by interior housing pulley 18 and exterior housing pulley 18 , which in turn retracts deadbolt 22 out of grating bore 41 . Pipes 80 prevent interference and binding in cable 20 . Grating 40 may then be opened, and safety pin 56 prevents unwanted re-closing of same. FIG. 7 depicts a single transwall actuator 10 (which would work well by itself); in the preferred embodiment a pair of transwall actuators 10 was used, so as to provide actuation for two deadbolts 22 .
In the preferred embodiment, most components of quick-release grating were made of metal, plastic, synthetic, or other appropriate material. E-clip 26 , safety pin spring 66 and deadbolt spring 24 were standard, off-the-shelf components. Cable 20 was steel cable, nylon, synthetic, or other appropriate material, and pipe 80 was PVC pipe, galvanized or aluminum pipe, or other appropriate material.
It is important to note that while most quick-release grating embodiments disclosed herein teach two deadbolts 22 , any number of deadbolts 22 (along with their associated cable 20 carried by pulleys 18 , and remote deadbolt assemblies 74 if appropriate) may be employed, from a quantity of one on upwards, depending on the size and configuration of grating 40 to be locked. Deadbolts 22 may or may not extend completely through frame bore 37 . In addition, although FIG. 5 depicts lock pins 70 constraining deadbolt spring 24 and E-clip 26 within remote deadbolt housing bore 77 , it is contemplated that the instant invention embrace any appropriate method known within the art of so doing.
While a preferred embodiment of the invention has been illustrated herein, it is to be understood that changes and variations may be made by those skilled in the art without departing from the spirit of the appending claims.
Drawing Item Index
1 quick-release grating
2 actuator
4 U-handle actuator
10 transwall actuator
11 actuator bar
12 handle
14 handle axle
15 arrow
16 lever
17 arrow
18 pulley
19 arrow
20 cable
21 pulley axis of rotation
22 deadbolt
24 deadbolt spring
26 E-clip
28 deadbolt spring stop
29 annular deadbolt spring stop
30 deadbolt spring stop bore
32 box
34 box bore
36 frame
37 frame bore
38 frame aperture
40 grating
41 grating bore
42 bar
43 grating side member
44 grating hinge
45 grating top member
46 box door
47 grating bottom member
48 box door lock
50 box door hinge
52 U-handle
53 U-handle cross ban
54 U-handle leg
55 arrow
56 safety pin
57 arrow
58 safety pin housing
59 arrow
60 safety pin housing bore
62 safety pin housing slot
64 guide pin
66 safety pin spring
68 safety pin spring stop
70 lock pin
72 arrow
74 remote deadbolt assembly
75 remote deadbolt housing
76 deadbolt stop
77 remote deadbolt housing bore
78 remote actuator
79 grating-mounted remote actuator
80 pipe
82 interior housing
84 exterior housing
86 wall | A quick-release grating comprising an actuator mounted to the grating, a frame to which the grating is rotatably mounted via of grating hinges, and a safety pin which prevents re-closure of the grating once it has been opened. The actuator comprises spring-loaded deadbolts which slide through frame and grating bores in order to lock the grating in position relative to the frame. The actuator is enclosed within a locked box which prevents unauthorized opening of the grating. An alternate embodiment quick release grating provides for an actuator disposed remote to the grating, which has the benefit of obviating the need to enclose the actuator within a locked box. An additional alternate embodiment quick release grating provides for deadbolts mounted to a grating top member and a grating bottom member. An additional alternate embodiment quick release grating incorporates a transwall structure, whereby an externally-mounted grating may be released via an internally-mounted remote actuator. | 4 |
BACKGROUND
Increasingly, consumers have come to rely on debit, credit, and stored value cards as a preferred vehicle to provide payment for transactions. Credit cards provide ready access to funds, offer financial protection superior to cash or checks, support loyalty programs, and allow consumers to take advantage of purchasing opportunities when funds may not be otherwise available. As debit and stored value cards have become increasingly popular, the need for consumers to carry cash or checkbooks is still further reduced.
Within the past few years, card associations and issuers have been providing transaction cards that are enhanced with features beyond the typical embossed account number, expiration date, cardholder name, and signature area. “Smart cards,” for example, have now come into popular use, and allow for enhanced security of both debit and credit cards by use of onboard integrated circuits to provide memory and optional microprocessor functionality. Smart cards and other enhanced or memory cards or tokens have found uses from replacements for simple embossed credit/debit cards, toll booth payment, ATM card replacements, and even Subscriber Identity Module (SIM) cards in cellular handsets.
Even though smart cards and electronics-enhanced cards have provided improvements over traditional credit cards, they suffer from a number of deficiencies. For example, electronics circuitry on enhanced financial transaction cards must receive externally-provided power to operate. To obtain power from a merchant's financial or Point-Of-Service (POS) terminal, contact-type smart cards use a physical connector interface; two of such interfaces are defined ISO standards 7810 and 7816. However, many types of cards not in physical contact with a POS terminal or other power source cannot operate, and therefore these cards are necessarily inactive at all other times. Alternatively, some enhanced financial transaction cards obtain power from a terminal-generated RF electromagnetic field by way of an inductor that is part of the card's circuitry. For example, ISO 14443 defines a popular contactless financial transaction card protocol. However, current contactless cards must be in close proximity to the properly modulated electromagnetic field in order to operate (10 cm in the case of ISO 14443-compliant cards). Due to the intentionally limited power and range of such short range fields, RF-powered cards cannot operate outside of the immediate area of a merchant's POS terminal, and may not have sufficient power in some cases to provide sophisticated electronic computations or support more power consuming circuitry such as displays. Further, embedded chips of some contactless smart cards often employ cryptographic security algorithms that can be “cracked” or decoded if the time and electrical current required for certain encryption or decryption operations is measured. Several demonstrations of this mode of account compromise have been documented, and thus, the possibility of surreptitious measurement of such parameters without knowledge of the cardholder presents a significant security risk.
What is needed then is an accessory device for a financial transaction card or token that provides power to the card or token to support operation of the card or token's features. What is further needed is an accessory for a financial transaction card or token that has an onboard power source that does not utilize the hazardous chemicals associated with typical power sources such as replaceable or rechargeable batteries. What is also needed is an accessory for a financial transaction card or token that has a power source that is rechargeable and has a form factor that may be easily carried in a pocket or purse. What is further needed is an accessory for a financial transaction token that can allow the token to operate in an environment significantly removed from a POS terminal. What is also needed is an accessory for a financial transaction token that utilizes an onboard power source to provide cryptographic security and protect the token when not in use. What is still further needed is a mobile accessory device that may reprogram a financial transaction card or token to encode a variety of types of account information, thereby allowing for payment flexibility using the financial transaction token. What is also needed is an accessory for a financial transaction token that allows the holder to view information stored in the token without being in proximity to a POS terminal. What is also needed is an accessory for a financial token transaction token that allows the holder to charge an energy storage device on the financial token and view the charge status of the financial tokens' energy source.
SUMMARY
There is provided an accessory device for a financial transaction token. The accessory has an onboard power storage device that enables a financial token or card that is in communication with the accessory to operate when the card or token is not in the proximity of a merchant terminal (e.g.; a POS terminal). In one implementation, the onboard power storage device includes a rechargeable battery or capacitor such as a thin-film capacitor that stores sufficient energy to power the accessory's onboard electronics and/or the electronics of a financial token in communication with the accessory. The accessory may be a subcomponent of another consumer device such as a computing device, communications device, an item of clothing, an item of jewelry, a cell phone, a PDA, an identification card, a money holder, a wallet, a purse, a briefcase, or a personal organizer.
In one implementation, the accessory includes a housing with a user interface, an integrated processor and storage, an onboard power source, and an interface to a financial token such as a smart card. The user interface optionally has an exposed region that is provided for encoding data including an account to pay for a transaction. The encoding renders data in several alternate or complementary formats, such as light- or laser-scannable bar coding on a display, electromagnetic signals that are transmitted to a merchant receiver, external contact pads for a contact-based pickup, and a magnetic stripe assembly. Using the exposed area, the accessory may complete a transaction with a merchant as a proxy for a financial token that is in communication with the accessory. In one implementation, a financial token that is in communication with the accessory may be reprogrammed by the accessory by accepting inputs from the accessory's user interface, and a the accessory's integrated processor transmits data to a processor embedded in the token, which in turn accepts the information and executes software in a processor located within the token to effect the reprogramming. This reprogrammable feature enables the holder of the accessory to secure the token by erasing a display or magnetic stripe or locking the token from unauthorized use. The accessory, when access is granted to a user, may perform calculations such as adding a tip from a predetermined tip percentage, or selecting payment to occur from a variety of different financial accounts. In one implementation, a magnetic stripe assembly in proximity to the token is reprogrammable, so that the token's embedded processor may select a particular account from input specified in the accessory's user interface, and provide instructions to reprogram the magnetic stripe. In another implementation, the accessory possesses read/write heads that are capable of reprogramming a financial token as the token is placed within or removed from a retaining cavity within the accessory's housing. The token's magnetic stripe may then be swiped through a conventional merchant magnetic stripe reader to initiate payment for a transaction. In yet another implementation, the account information or transaction authorization protocol stored within a financial token's memory is relayed to an accessory with which it is in communication, and a financial transaction is completed by the accessory in proxy for or in lieu of the token. In another implementation, the token also includes a memory that may optionally be maintained by the onboard power source located within the accessory.
In another implementation, an accessory for a financial token provides a charging current to an energy storage device located within the financial token. In this way, a relatively small capacity energy storage element can be recharged by placing the token in communication with the accessory, such as by sliding the token within a slot or cavity within the accessory device. An electrical interface may then proceed to charge the financial token's energy storage element through current provided by a power source in the accessory, or through relaying charging current that is obtained by the accessory's external charging interface. In another implementation, the accessory for a financial token possesses a charging circuit that can utilize an onboard energy generation capability to recharge the financial token's energy storage element and optionally recharge the power source within the accessory.
In another implementation, an accessory for a financial transaction card is provided that accepts and retains the card within a protective housing. The card may have a substantially rigid substrate not unlike conventional credit cards and an onboard energy storage device such as a thin-film capacitor. The card includes, in one implementation, a conventional or reprogrammable magnetic stripe assembly that is disposed proximal the substrate. As mentioned previously, the reprogrammable substrate may be configured by a an embedded processor that is commanded through inputs provided to an accessory device with which the card is in communication. In one implementation, the user provides input through a keyboard or an array of contact pads or blister buttons on or integrated into the accessory's housing Alternately, the user input section may include a biometric input device that scans fingerprints or other biometric data to authenticate the user of the accessory, or may have a pressure-sensitive area for inputting a predetermined access glyph such as by the user dragging a fingertip over a pad to reproduce a symbol that the user has previously identified. In one embodiment, the housing of the accessory retains and protects the card from unauthorized access, such as by preventing physical access to the card through a locking retaining mechanism, and/or by providing shielding against electromagnetic radiation including RF signals.
Various features and advantages of the invention can be more fully appreciated with reference to the detailed description and accompanying drawings that follow.
DESCRIPTION OF THE DRAWINGS
The features, objects, and advantages of embodiments of the disclosure will become more apparent from the detailed description set forth below when taken in conjunction with the drawings, in which like elements bear like reference numerals.
FIG. 1 depicts a block diagram of an exemplary implementation of an accessory for a financial transaction token including an electrical/data interface;
FIG. 2 illustrates possible alternate implementations of the electrical/data interface seen in FIG. 1 ;
FIG. 3 shows an exemplary implementation of a financial token and an accessory for a financial transaction token;
FIG. 4 shows a second exemplary implementation of a financial token and an accessory for a financial transaction token;
FIGS. 5A-5B show illustrations of a pendulum and piezoelectric crystal implementation of the charging circuit seen in FIG. 1 ;
FIGS. 6A-6C show illustrations of a movable mass and piezoelectric crystal implementations of the charging circuit seen in FIG. 1 ; and
FIGS. 7A-7B illustrates two additional exemplary embodiments for the accessory for a financial transaction token.
DETAILED DESCRIPTION
A block diagram for an exemplary implementation of an accessory 100 for a financial transaction token is seen FIG. 1 . The accessory 100 comprises an assembly 102 that houses, supports, and/or integrates the components shown in FIG. 1 . Those of skill in the relevant arts understand that the assembly 102 may be integrated within a consumer product such as a cell phone or PDA (with embodiments shown in FIGS. 7A and 7B , respectively), or may comprise a stand-alone assembly. The accessory includes an integrated processor 105 , which those of skill in the relevant arts will appreciate may comprise a microprocessor chip, a microcontroller chip, an ASIC, a digital signal processor (DSP), or a smart card chip. The processor 105 is coupled to a power circuit 115 . The power circuit 115 provides power to the accessory's electronic components 105 , 110 , and 130 , and may further include signals indicating charging or connection status. The processor 105 is further coupled to signal busses 120 , 122 , and 125 , which those of skill in the relevant arts will recognize may be comprised of a plurality of individual dedicated signal circuits, commonly shared signal busses, bidirectional signal circuits, unidirectional signal circuits, or combinations thereof. In one implementation, signal busses 120 , 122 , and 125 comprise a single commonly shared address/data bus with associated control signals. The integrated processor 105 is coupled to a storage 110 through signal bus 125 . Those of skill in the relevant arts appreciate that the storage 110 may comprise any number of electronic, magnetic, or electromechanical storage devices such as miniature hard drives; SRAM memory; DRAM memory; ROM, PROM, EEPROM, or flash memory; or combinations thereof, and such storage may be included in total or in part upon the same integrated circuit substrate as the processor 105 . The storage 110 , if of volatile type, may have its data values preserved by power provided by the connected power circuit 115 . Data stored in memory 110 may include code or program instructions which, when executed by processor 105 , performs at least part of a command sequence requested by a user through the user interface 130 .
An onboard power source 150 is coupled to and energizes the power circuit 115 . Those of skill in the relevant arts will recognize that energy storage devices such as batteries, inductors, capacitors, or combinations thereof may be utilized to implement the power source 150 . In one implementation, power source 150 comprises a thin film capacitor, and may utilize a single dielectric or a multilayer configuration alternating conducting layers and dielectric layers. A number of dielectrics such as polyester, polypropylene, polycarbonate, polystyrene, polyimide, PTFE, PET, and combinations thereof may be utilized in such thin film capacitor implementations. A substantially planar thin film capacitor implementation is beneficial for implementation in the instant accessory device 102 , as the substantially planar form factor may be useful in minimizing the overall size of the accessory's footprint. In another implementation, power source 150 may be implemented with any number of conventional rechargeable and non-rechargeable batteries such as alkaline batteries, lithium ion batteries, nickel-cadmium batteries, and nickel metal hydride batteries.
The power source 150 also provides current to a power line 119 of a financial token interface 145 either directly through a connection 116 coupled to the power circuit 115 , or via output 118 from a voltage regulator 151 which receives power from a coupling 117 to the power source. Those of skill in the relevant arts appreciate that the regulator 151 may be implemented with any number of conventional voltage regulators; for example, but not by way of limitation, such regulators may include alone or in combination: zener diodes, voltage regulator circuits, voltage translators, transformers, voltage dividers, switched power supplies, silicon controlled rectifiers, triacs, potentiometers, and the like.
The power source 150 is coupled 157 to a charging circuit 155 . The charging circuit may also be coupled 156 to an external charging interface 158 . Those of skill in the relevant arts will readily recognize that the charging interface 158 may be implemented with electrical contacts to an external circuit, or via an inductor for receiving power via electromagnetic radiation. In one implementation, charging circuit 155 includes one or more photovoltaic cells, coupled to the power source, which produce electricity upon exposure to light. In another implementation, charging circuit 155 further includes one or more piezoelectric crystals electrically connected, via coupling 157 , to the power source 150 , and a movable mass that strikes the piezoelectric crystals as the token 100 is moved. Turning to FIG. 5A , a piezoelectric charger implementation of the charging circuit 155 is shown. A movable pendulum mass 500 rotates 505 , preferably in a substantially planar motion, about a pinned end 510 . The pendulum mass 500 also has an impact end 525 , that is disposed between and may strike either of two piezoelectric crystals 520 , 521 . As the crystals 520 , 521 are electrically coupled 157 to the energy storage device 150 , impacts of the pendulum mass 500 cause pulses of current to be delivered to the energy storage device 150 thus charging the storage device 150 . FIG. 5B provides an illustration of the pendulum 500 moving 506 to strike crystal 521 , and likewise, the pendulum mass 500 may move the opposite direction to strike the other crystal 520 . Turning to FIG. 6A , an alternate mass/piezoelectric implementation of the charging circuit 155 is shown in cross section. A charger housing 600 constrains piezoelectric crystals 520 , 521 from movement, and crystals 520 , 521 are electrically coupled 157 to the power source 150 . A movable mass 625 is disposed between the crystals 520 , 521 within in the charger housing 600 , and the mass is free to move within the spaces defined 610 by the charger housing 600 and the crystals 520 , 521 as the appliance 100 is moved. Those of skill in the relevant arts understand that charger housing 600 may be implemented by many geometrical shapes that constrain the piezoelectric crystals 520 , 521 while allowing mass 625 to move in the available space 610 . For example, but not by way of limitation, charger housing 600 may be a cylindrical tube with mass 625 comprising a dense spherically-shaped object such as a metal ball bearing or a dense cylindrical metal slug. Similarly to FIGS. 5A-B , as the mass 625 strikes crystals 520 , 521 , pulses of current are produced and charge the power source 150 . An example of the charging circuit of FIG. 6A is shown in action in FIG. 6B . When the accessory 102 containing charging circuit 155 is tilted 620 with respect to ground horizontal, the force of gravity propels mass 625 toward 630 one of the piezoelectric crystals 521 , whereupon the mass 625 strikes the crystal 521 producing a current which is electrically coupled 157 to the power source 150 . Turning to FIG. 6C , another implementation of a charging circuit 155 is shown with two crystal/mass housings 600 , 650 . In this illustration, housings 600 , 650 have been laid out in the charging circuit 155 with central axes oriented orthogonally with respect to each other. Similarly to FIGS. 5A and 5B , a mass 675 is also movably disposed between two piezoelectric crystal elements 660 , 661 , that are coupled 157 to the power source 150 , and the mass 675 is constrained by the housing 650 . With this arrangement, rotation of the accessory 100 with respect to horizontal produces alternate mass/crystal strikes between the vertically disposed housing 650 and the horizontally disposed housing 600 . Those of skill in the relevant arts appreciate that any number of crystal/mass/housing assemblies may be included in the charging circuit 155 , and many possible geometric alignments are possible beyond disposal along orthogonal central axes. Those of skill in the relevant arts also appreciate that inertia of the mass 625 , 675 may be used to cause striking forces as the charging circuit 155 is moved, independently from tilting the device. Therefore, movements such as walking or riding a vehicle may provide sufficient physical displacement to cause charging of the power source 150 to occur.
Returning to FIG. 1 , a user interface 130 is also provided, and is coupled to the power circuit 115 and to the integrated processor 105 via signal bus 122 . In one implementation, the user interface may include one or more conventional displays 135 that may output text, graphics, or a combination. The display 135 may be implemented in such formats as a liquid crystal display, a thin film transistor display, touch-sensitive screen, or organic LED display. The user interface 130 also includes an optional data entry apparatus 140 . In one implementation, the data entry apparatus 140 may include an array of buttons labeled in a manner such as a QWERTY keyboard, a touch pad, a touch screen, or in a more simplistic implementation, a telephone touch pad with alphanumeric key assignments. In one implementation, the buttons in the data entry apparatus 140 may comprise blister buttons commonly known in the art. The user interface 130 may also include an optional on/off button that activates the accessory 100 for selecting desired account access, performing a calculation, or authenticating a user.
An external interface 137 is also provided. The external interface 137 enables the accessory 100 to communicate with external devices such as computer terminals, computer networks, or point of sale (POS) terminals. The interface 137 receives data and/or commands for displaying text or graphical information from bus 122 , and receives power from power circuit 115 . The interface 137 may also receive data from an outside source such as a wireless POS terminal, a financial institution, or a personal computer, and relays the data to the integrated processor 105 through data bus 122 . Through user input to the data entry device 140 , a variety of data may be provided to the external interface. In one implementation, the information provided to be output from the interface 137 may comprise health care information, personal identity information, biometric data, music, video data, or a combination thereof, and is considered interchangeable with the term “account data” used herein.
Turning to FIG. 2 , exemplary implementations 200 of the external interface 137 are shown. External interface 137 is depicted with an optional shielding element 137 A, which allows desired electromagnetic, optical, or radiative signals to penetrate while protecting the external interface 137 from physical abuse or damage. The accessory 100 may optionally have areas outside of the external interface 137 shielded from physical abuse or otherwise acceptable forms of electromagnetic radiation. Some of the acceptable signals that are allowed to penetrate the shielding 137 A may include, but are not limited to, signals accompanying a magnetic field, RFID signals, IrDA signals, visible light, invisible light, modulated laser, and/or modulated RF communication signals. By way of example and not by way of limitation, selective shielding element 137 A may comprise a clear plastic shield, conformal coatings, an opaque plastic shield, or a clear thin film, depending on the implementation of external interface 137 .
Non-limiting examples of the external interface are shown at reference numeral 200 , and include a magnetic stripe assembly 210 , an antenna and/or transceiver 220 , a display screen 230 , electrical contacts 240 , and a touch screen 250 . The magnetic stripe assembly 210 may comprise, in one implementation 210 A, a reprogrammable magnetic stripe 210 B that accepts data and/or commands from the processor 105 and formats and renders that data into a form on a magnetic stripe that is readable by conventional merchant magnetic stripe-reading POS terminals. In this manner, the processor 105 may program a particular account for use in a transaction as a function of user input selecting the account. Alternatively, the processor 105 may erase the magnetic stripe of the assembly 210 , rendering the card useless in the event of its loss or theft. In the implementation shown 210 A, the magnetic stripe assembly 210 B at least partially slidably moves 210 C into and out of the housing 102 of the accessory 100 (partial view shown), allowing the accessory 100 to conduct a financial transaction at a point of sale terminal that includes a magnetic stripe reader.
Continuing with FIG. 2 , another implementation of the external interface 137 is shown as an antenna and/or transceiver 220 . The antenna 220 may include commonly used loop inductors such as the one shown 220 A, cellular phone antennae, WiFi antennae or in those shown in related ISO standards for RF-readable smart cards. With such an interface, account data may be translated, modulated and transmitted by the accessory in a manner acceptable by an RF contactless merchant Point-Of-Service (POS) terminal, a 802.11 WiFi or WiMax network, or by a cellular or RF communications network.
The external interface 137 may also be represented with a display screen 230 . Account data may be rendered in the form of an optically-readable area, such as a one dimensional or two dimensional bar code 230 A. In this manner, merchant POS terminals may optically scan the display area 230 with conventional laser scanners, and obtain account information without the need for expensive contactless RF POS terminals. As the display is electronically reconfigurable with information provided by the processor 105 , the accessory 100 may represent any number of accounts for transaction payment based on the user's preference and input to the user interface 130 . Also, as a security feature, the display may be blanked or filled with a decorative or entertaining graphic when the user has not provided an optional security access code, pad stroke, or pin number to the user interface 130 .
External contacts 240 are yet another alternative implementation of the external interface 137 shown in FIG. 2 . With the accessory 100 possessing physical contacts such as an array of conductive pads or shapes 240 A, the accessory may be placed in physical contact with a merchant POS terminal, and the external contacts 240 may establish connectivity to the merchant's financial processing system. The integrated processor 105 may relay account-related information to the merchant POS terminal through the contact interface, thereby allowing the accessory 100 to be utilized with the large number of preexisting merchant POS terminals that accept smart cards. As with the other implementations 210 , 220 , 230 , and 250 of the external interface 137 , a combination of techniques may be utilized within the external interface to provide flexibility of use and ease of merchant access to account information.
Alternatively, the external interface 137 may comprise a touch screen 250 , wherein text and/or graphics may be displayed, and user input may be accepted by touching selected areas of the screen. For example, but not by way of limitation, in an implementation shown at reference numeral 250 A, a user is prompted to tap on one of a plurality of account descriptors, thereby selecting an account to complete a transaction. Those of skill in the relevant arts also appreciate that tapping the screen may be combined with using pointing devices such as a joystick, direction buttons, or selection wheels. In one embodiment, a user may provide authentication information by touching the display 250 in specified areas to indicate sequences of pin numbers, selected graphical elements, or drag strokes that match a predetermined access criterion stored within the storage 110 .
Turning to FIG. 3 , an implementation of the accessory 100 is shown along with one possible financial token embodiment 300 . The substrate of the financial token 300 , in one implementation, takes the form of a transaction card 300 that is substantially rigid and thin as are conventional credit or debit cards, and possesses substantially similar dimensions as existing credit, debit, stored value, or smart cards. In one implementation, the thickness of card 300 exceeds that of conventional credit, debit, or stored value cards in order to accommodate circuitry, electronics, displays, and/or interface elements. The substrate of the card 300 contains an embedded processor 305 and memory 310 .
A front side of the token 300 is shown with an array of buttons 312 and a display 335 for outputting alphanumeric text or graphics, such as an account number and expiration date. An array of physical contacts 350 is shown, which may be utilized in conjunction with a POS terminal, or the electrical/data interface 145 . In the illustrated implementation, the token 300 may be placed within the accessory 100 by, for example, but not by way of limitation, sliding the token 300 into 322 a slot 323 defining a cavity within the accessory housing 102 . The accessory housing 102 retains the token 300 until the user actuates a hardware mechanism such as a latch (not shown) that retains the token 300 within the cavity within the accessory housing 102 . Alternatively, the token 300 could be retained by an electromechanical latch (not shown) coupled to the power source 150 and the integrated processor 105 , wherein the token could be released upon an execution of a command by the processor 105 . For example, but not by way of limitation, if a user entered a valid authorization code into the touch screen interface 250 A, the processor determines the code is valid and provides a command to the electromechanical latch to release the token from the accessory. Alternatively, a drive element (such as those that actuate Compact Disk player disk slots in portable CD players) could eject the card through the slot 323 upon receiving a command to eject the card from the processor 105 .
The accessory 100 is shown with a user input mechanism comprising an array of buttons 140 , and a touch screen 250 A as described in relation to FIG. 2 . An external charging interface 158 is provided on a side panel of the housing of the apparatus 102 . The touch screen, as with most conventional Portable Digital Assistants (PDAs), both accepts input through strokes or taps and produces output for viewing by the user. Status information and commands may be entered by the user tapping on or dragging on the touch screen 250 A.
By way of example but not limitation, the accessory 100 includes, in the illustrated embodiment, an array of electrical contacts 353 comprising at least a portion of the financial token internal interface 145 . When the token 300 is fully inserted 322 into the cavity of the accessory housing 102 , the contacts 353 proximally engage with the contacts 350 on the token 300 , thereby establishing electrical connectivity. As described below other implementations of the internal interface 145 with the token 300 are possible, whereby electrical coupling between the token 300 and the accessory 100 are accomplished using all or partially contactless approaches.
In one implementation, the user turns on the accessory 100 by depressing an on/off button 305 , and then produces a stroke on the pad/screen 250 A by dragging a fingertip or stylus across the pad or screen area 250 A to reproduce a symbol or glyph substantially similar to a symbol pre-programmed into the integrated processor 105 and storage 110 (embedded, not shown). Once the symbol or glyph is entered by the user on the pad/screen 250 A, the processor 105 compares its features with a pre-stored graphical implementation and if the symbol's features are within a predetermined range, the accessory 100 is enabled for use, otherwise an invalid entry message is output to display 250 A and use is further inhibited until the successful glyph or symbol is entered.
As further explanation of the coupling between the accessory 100 and the token 300 , we return to FIG. 1 . The accessory 100 includes an internal electrical/data port or interface 145 that is coupled to the integrated processor 105 through the signal bus 120 and to a power signal through power line 119 as described above. Since the signal bus 120 and power line 119 carry potentially bidirectional signals, data and/or power signals may flow into or out of the electrical/data interface 145 . In one implementation, a power signal is delivered to and energizes at least part of the coupled financial token 300 through the electrical data interface 145 . Using the supplied power, the financial token 300 may operate onboard circuitry to exchange data with the accessory 100 , receive commands from the accessory 100 , or charge an energy storage element embedded within the financial token 300 from the accessory's power source 150 . Through the interface, the integrated processor 105 may also determine a charge state of the energy storage element within the token, and display the status in the user interface 130 . Also, memory 310 within the financial token 300 may be queried through commands issued by the bus 120 through the interface 145 , and the processor 105 may receive and process the results of the data returned through the interface 145 . For example, but not by way of limitation, the processor 105 may request data regarding a financial account from the financial token 300 , and the accessory 100 may conduct a transaction using the external interface 137 , in lieu of conducting the transaction using only the financial token 300 . As another example, but not by way of limitation, the processor 105 may send commands and account data to the financial token 300 , configuring the token 300 for use for a particular account as selected through the user interface 130 .
The internal port or interface 145 may be coupled to a financial token 300 by any number of electrical coupling techniques, including electrical contacts between the accessory 100 and the financial token, RFID signal transceivers, IrDA signal infrared transceivers, visible light transceivers, invisible light transceivers, magnetic strip read/write heads, modulated laser transceivers, modulated RF communication transceivers, and combinations thereof. Those of skill in the relevant arts appreciate that a combination of coupling techniques may be utilized, such as by providing a data signals through electrical contacts while a power signal is delivered by an electromagnetic field from the accessory 100 to an inductor located within the token 300 .
Turning to FIG. 4 , another implementation of an accessory 100 is shown with a financial token 300 . The token 300 has an embedded processor 305 , a memory 310 , and an energy storage element 451 such as a thin film capacitor electrically coupled to the token's electronic circuitry. The token 300 has a magnetic stripe 430 , which like conventional magnetic stripe fields, is readable by preexisting merchant POS terminals or ATMs. The magnetic stripe 330 may optionally be programmable by data and commands sent from the an embedded processor within the token 305 and memory 310 .
Similarly to FIG. 3 , the token 300 may be placed within the accessory 100 by, for example, but not by way of limitation, sliding 322 the token 300 into a slot 323 defining a cavity within the accessory housing 102 . The accessory housing 102 retains the token 300 until the user actuates a hardware mechanism such as a latch (not shown) that retains the token 300 within the cavity within the accessory housing 102 . Alternatively, the token 300 could be retained by an electromechanical latch (not shown) coupled to the power source 150 and the integrated processor 105 , wherein the token could be released upon an execution of a command by the processor 105 . For example, but not by way of limitation, if a user entered a valid authorization code into the touch screen interface 250 A, the processor determines the code is valid and provides a command to the electromechanical latch to release the token from the accessory. Alternatively, a drive element (such as those that actuate Compact Disk player disk slots in portable CD players) could eject the card through the slot 323 upon receiving a command to eject the card from the processor 105 .
In this implementation, the accessory 100 includes an internal set of electromagnetic read and/or write heads 450 which comprise one possible embodiment of the electrical/data interface 145 . As the token 300 is moved 322 into the cavity 323 , the heads 450 traverse a significant portion of the length of the magnetic stripe 430 while in proximity to the surface of the magnetic stripe. If the heads 450 are so enabled by the integrated processor 105 , data may be read from and/or written to the magnetic stripe 430 during insertion 322 or extraction of the token 300 . Such data, as mentioned previously is processed by the integrated processor 105 by transmitting the data to or receiving the data from the data bus 120 which is in turn coupled to the internal interface 145 . In one example, but not by way of limitation, the token's magnetic stripe 430 is erased by the read/write heads 430 upon insertion 322 to the accessory 100 , and is programmed with account data specified in the user interface 140 upon removal of the token 300 from the accessory.
Also shown on the card 300 is an optional array of physical contacts 350 , which, as described above come into proximity with internal electrical contacts 353 when the token 300 is inserted 322 into the cavity 323 . The contacts 353 comprise at least a portion of the financial token internal interface 145 . When the token 300 is fully inserted 322 into the cavity of the accessory housing 102 , the contacts 353 proximally engage with the contacts 350 on the token 300 , thereby establishing electrical connectivity. As mentioned previously, other implementations of the internal interface 145 with the token 300 are possible, whereby electrical coupling between the token 300 and the accessory 100 are accomplished using all or partially contactless approaches.
Turning to FIG. 7A , an alternate implementation of the accessory 100 is shown as a communications device such as a cell phone. The accessory housing 102 includes a slot 323 for a financial token 300 , or optionally, the financial token 300 is permanently or semi-permanently integrated within the hardware of the accessory 100 . The accessory 100 has a display 230 , and a data entry keypad 140 , allowing interaction with the accessory to issue user commands. As mentioned previously, the accessory 100 may be used to complete a financial transaction without removing token 300 , or the accessory 100 may configure the token 300 , using commands entered through the user interface 140 , to select a particular transaction payment account to be transmitted to the token through the internal electrical interface (not shown). In a similar spirit, FIG. 7B illustrates another implementation of the accessory 100 , shown as a consumer device such as a personal digital assistant (PDA). The accessory housing 102 includes a slot 323 for a financial token 300 , or optionally, the financial token 300 is permanently or semi-permanently integrated within the hardware of the accessory 100 . The accessory 100 has a touch screen display 250 A for entry and output of commands and data, a data buttons and pads 140 . As mentioned above, the accessory 100 may also be used to complete a financial transaction without removing token 300 , or the accessory 100 may configure the token 300 , using commands entered through the user interface 140 , to select a particular transaction payment account to be transmitted to the token through the internal electrical interface (not shown).
The above description of the disclosed embodiments is provided to enable any person of ordinary skill in the art to make or use the disclosure. Various modifications to these embodiments will be readily apparent to those of ordinary skill in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the disclosure. Thus, the disclosure is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein. | There is provided an accessory device for a financial transaction token. The accessory has an onboard power storage device that enables a financial token or card that is in communication with the accessory to operate when the card or token is not in the proximity of a merchant terminal (e.g.; a POS terminal). In one implementation, the onboard power storage device includes a rechargeable battery or capacitor such as a thin-film capacitor that stores sufficient energy to power the accessory's onboard electronics and/or the electronics of a financial token in communication with the accessory. The accessory may be a subcomponent of another consumer device such as a computing device, communications device, an item of clothing, an item of jewelry, a cell phone, a PDA, an identification card, a money holder, a wallet, a purse, a briefcase, or a personal organizer. | 6 |
[0001] This invention was made with the United States Government support under Contract No. 0376/FA8650-04-D-1712 awarded by AFRL/SNJM and AFRL/DE. The Government has certain rights in this invention.
FIELD OF THE INVENTION
[0002] This invention relates generally to wavefront correction or compensation devices. More particularly, this invention relates to a compact, high-speed deformable mirror having a membrane which deforms in the presence of a voltage differential across the membrane.
BACKGROUND
[0003] Compact, high-speed wavefront correction devices having deformable mirrors (DMs) are needed for adaptive optics (AOs). In particular, devices are needed to correct wavefront aberrations or distortions, often due to turbulence and/or system optical aberrations. Perhaps the most challenging applications of adaptive optics involve corrections of turbulence on airborne platforms. In this type of environment, a large number of actuators (in excess of 100) are required to actually deform the mirror. A large phase throw (>8 microns) and high, closed-loop bandwidths (typically >1 kHz) are also needed. In addition, the entire adaptive optics system, including the DM wavefront corrector and its controller, must be compact. This requirement drives the optical beam diameter down to 1-2 cm.
[0004] Large DM actuator spacing (≧2 mm) is the primary reason for the large size and weight of existing adaptive optics systems. The size of the entire adaptive optics bench tends to vary linearly with actuator spacing. The F-number of the optical system is typically invariant. Therefore, the optical bench size varies linearly with the beam size, and the beam size depends on DM actuator number and spacing. For example, current micromachined membrane and piezoelectrically actuated DMs have actuator spacings of 2 mm and ≧2.5 mm, respectively. An adaptive optics system that relies on these technologies, and provides 37 actuators across the aperture, then requires a 7.4-9.3 cm minimum beam size on the optical bench. In airborne lasercom transceivers, however, the optimum beam size on the optical bench is 1-2 cm. If the number of actuators across the array exceeds about 7-9 (i.e., 37-61 actuators in a hexagonal array), existing DM technologies are simply too big to fit on the lasercom optical bench without requiring a significant increase in bench size and weight.
[0005] Conventional bulk micromachined membrane DMs sold today (e.g. FIG. 1 ) are electrostatically driven using an array of actuators 100 below the membrane 102 . A DC voltage is applied to the membrane to deform it into a static parabolic shape (as shown by the dashed lines in FIG. 1 ), thereby producing tensile stress in the membrane that acts to pull it back into a flat shape. By increasing or decreasing the applied voltage at the metal actuators below the membrane, the membrane is distorted from the parabolic profile, thereby producing the equivalent of local piston stroke.
[0006] These membrane DMs suffer from several drawbacks: 1) The membrane is made from silicon nitride, which may undergo dielectric relaxation when DC biased, resulting in short-term drift in the deflection vs. voltage response; 2) Low electrostatic pressure and/or high membrane tensile stress limit the smallest effective actuator pitch (i.e., the spacing between the same edge of adjacent actuators) to 2.0 mm or more; 3) A pre-biased membrane also has limitations in the amplitude of correction at high spatial frequencies (f s =(2*actuator pitch) −1 ˜0.5 mm −1 ); 4) To allow room for the membrane to achieve a parabolic shape, the gap “d 1 ” between the membrane and the metal conductors on the backplane is on the order of 40-100 microns; 5) These membrane DMs can achieve only a modest optical phase throw of ˜4 microns, even though they are operated at control voltages of 200-300 V. Electrostatic devices exhibit a quadratic dependence of electrostatic pressure P on the voltage V and gap d, according to the equation:
[0000] P=∈ o ( V/d ) 2
[0007] This relationship says that, all other parameters being equal, a device having a smaller gap will operate at a lower voltage; 6) Due to large gap and high values of membrane residual tensile stress (>100 MPa), the actuator spacing is limited to about 2 mm and significant coupling between actuators is observed; 7) The total number of actuators for a membrane DM is higher than for other technologies because membrane mirrors require additional actuators outside the optical aperture to achieve large deflections at the pupil edge that are necessary to reproduce Zernike polynomials; 8) The minimum actuator spacing dictates the total size of the membrane/actuator array for a given size and number of actuators across the array: 9) Membrane DMs require a second optical element to remove the parabolic curvature from the wavefront; 10) Current membrane DMs are not hermetically sealed and operate in 1 atm air pressure, which strongly dampens membrane oscillations; and 11) They are sensitive to microphonics and electrostatic damage. These features of the conventional membrane DMs, while minimizing costs, significantly reduce membrane dynamic range at high temporal and spatial frequencies.
[0008] Hence, there is a need for a compact, high-speed DM to overcome one or more of the drawbacks identified above.
SUMMARY OF THE INVENTION
[0009] The invention herein disclosed is a deformable mirror (DM) that advances the art and overcomes several of the problems articulated above. This invention provides a DM wavefront correction device that operates at high frequencies in the kHz range, exhibiting large optical phase throw at high spatial frequency. At low spatial frequency, typical of current membrane DM technology, this invention operates at much lower voltage. This invention also provides methods to obtain very low stress membranes, low loss and manufacturable transparent conductor design, and methods to drive the device for accurate high order Zernikes with fast membrane response.
[0010] In particular, and by way of example only, according to an embodiment, provided is a DM including: a deformable membrane having a reflective front surface and a back surface; a plurality of electrostatic actuators positioned in close proximity to the back surface of the membrane to define a first gap between the plurality of electrostatic actuators and the back surface of the membrane; at least one transparent conductor positioned in close proximity to the front surface to define a second gap between the at least one transparent conductor and the front surface of the membrane; wherein a bias voltage is applied to the transparent conductor and actuator voltages are applied to the plurality of electrostatic actuators; the deformation of the membrane is induced by voltage differentials between the bias voltage applied to the transparent conductor and the actuator voltages applied to the plurality of electrostatic actuators. The bias and actuator voltages are all relative to the membrane voltage, which is typically held at earth ground.
[0011] Specifically, the membrane, which can be composed of more than one layer of material, has a low net residual stress of all the layers. e.g. 0-50 MPa tensile. This low net residual tensile stress range is necessary for low voltage operation. However, because a conventional membrane DM requires a large gap to allow the membrane to deform into a concave shape, a transparent conductor is included in the design to “pull up” the membrane in order to maintain a flat quiescent state and thereby reduce the gap. High optical phase throw at low voltage is achieved by reducing the gap between the membrane and the adjacent conductors to <40 microns, and preferably <20 microns. These novel design parameters permit the use of small actuator pitch values of <1 mm, and achieve high optical phase throw (i.e., 4-8 microns) at high spatial frequencies of >0.5 mm −1 (spatial frequency=(2*actuator pitch) −1 . Thus, for the thin deformable membrane (TDM) device, low activation voltage (<300 V) and high temporal and spatial frequency response are simultaneously possible for a membrane mirror by using low residual tensile stress (<50 MPa tensile), a small membrane-to-actuator and transparent conductor-to-membrane gap (<40 microns), and low pixel spacing (<1 mm). Furthermore, the transparent conductor allows more accurate high-order Zernike profiles to be generated than those prior art with no transparent conductor.
[0012] The transparent conductor utilizes a proprietary low-loss Transcon™ film, which can have 0.2-1% absorption in the infrared, depending on process conditions, for handling high optical power density. The transparent conductor utilizes an easily manufacturable design that makes assembly of a controlled gap simple.
[0013] In another embodiment, provided is a method of compensating for distortions in a wavefront received by the adaptive optics, the method including: applying a bias voltage to at least one transparent conductor positioned in close proximity to a first surface of a deformable membrane; applying actuator voltages to a plurality of electrostatic actuators structured and arranged in close proximity to a second surface of the membrane; generating voltage differentials between the bias voltage applied to the transparent conductor and the actuator voltages applied to the plurality of electrostatic actuators; and reflecting the wavefront having distortions off the first surface of the membrane wherein the voltage differentials induce a predetermined deformation in the membrane, and further wherein the deformation in the membrane compensates for the distortions in the received wavefront. The bias and actuator voltages are all relative to the membrane voltage, which is typically held at earth ground.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] FIG. 1 is a representation of a deformable membrane/mirror known in the prior art;
[0015] FIG. 2 is a deformable mirror according to a present embodiment;
[0016] FIG. 3 is a deformable mirror incorporating a silicon nitride membrane according to an embodiment.
[0017] FIG. 3( a ) is a sectional view of a portion of the deformable mirror of FIG. 3 expanded to show portions thereof in greater detail.
[0018] FIG. 4 is a deformable mirror incorporating a polymer membrane according to an embodiment.
[0019] FIG. 5 is the deformable mirror of FIG. 2 , which deforms consistent with a uniform voltage differential present across the surface of a deformable membrane; and
[0020] FIG. 6 is a method for correcting or compensating for wavefront aberrations present in a received wavefront, according to an embodiment.
DETAILED DESCRIPTION OF THE INVENTION
[0021] Before proceeding with the detailed description, it should be noted that the present teaching is by way of example, not by limitation. The concepts herein are not limited in use or application with one specific type of DM. Thus, although the instrumentalities described herein are for the convenience of explanation, shown and described with respect to exemplary embodiments, the principles herein may be equally applied in other types of DMs.
[0022] FIG. 1 depicts a deformable mirror as known in the art. A compact, high-speed, wavefront corrector or DM 200 according to the present disclosure is presented in FIG. 2 . The DM 200 is scalable to incorporate a large number of actuators 218 , requires an operating voltage at or below 50 V for low spatial frequency operation, and achieves a mechanical resonance frequency greater than 2 kHz, thereby allowing for substantially continuous wavefront corrections. Reduced voltages equate to a reduced circuit density, which leads to smaller, lighter weight control electronics. For example, a reduction in operating voltage from 300 V to 50 V reduces power consumption by at least a factor of 10×.
[0023] As shown in FIG. 2 , the DM 200 includes a thin membrane 202 , having a top surface 204 and a bottom surface 206 . Specifically, the membrane 202 may be of any material(s), such as a semiconductor, metal, and/or insulator. In at least one embodiment of the membrane, the membrane can be a silicon-based material, for example, a silicon or a silicon nitride Film, on the order of micron(s) thick, released from bulk micromachining of a silicon wafer, and then coated with metal and highly reflective layer(s). In another embodiment of the membrane, the membrane can be a polymer film, on the order of micron(s) thick, that has been mounted on a supporting structure, like metal rings, and then coated with a highly reflective coating.
[0024] The deformable mirror 200 is sealed within a hermetically packaged cell 208 (not shown). The cell is placed in vacuum, or in an inert gas to stiffen the membrane response and thereby increase the resonant frequency of the membrane 202 . The optimal pressure level of the inert gas to get the largest resonance frequency with the fastest membrane response will depend on the details of the membrane design. Furthermore, since the cell 208 is shielded from external fields by the transparent conductor, the membrane 202 is relatively insensitive to electrostatics and acoustic disturbances.
[0025] Residual tensile stress in the membrane 202 (indicated for example by arrow 210 in FIG. 2 ) is on the order of 0-50 MPa, as opposed to >50 MPa for prior art devices. Optimization of membrane stress to between 0-50 MPa tensile helps to minimize the control voltage required, and hence the size of the voltage source, controller, etc. (not shown). The stresses of the individual layers in the membrane are optimized such that the total stress of the membrane is 0-50 MPa tensile. This low stress range allows for high spatial frequency operation, or low activation voltage in the case of low spatial frequency operation.
[0026] The steps of a method to control net membrane residual stress to 0-50 MPa tensile are a function of several parameters as discussed in greater detail as follows. If the membrane has only one layer, the stress of that single layer must be controlled through its deposition process. If the membrane consists of more than one layer, and the deposition process for each layer is controllable to well below 50 MPa tensile stress, then the complete membrane stack can be 0-50 MPa net tensile stress. If the membrane consists of more than one layer, and the deposition process for each layer is high, say more than 50 MPa, then the thickness of the of the higher stress film can be reduced to reduce the net stress.
[0027] If the stress and/or net stress are compressive, then thermal annealing can be used to shift the stress level. Annealing the individual layers and/or the total membrane stack at an elevated temperature can be used as a technique to shift the net stress of the film. By way of example, annealing compressive Nb 2 O 5 —SiO 2 reflective layers sputter deposited on Al-coated silicon nitride membrane at room temperature to 200-300 C makes the stack less compressive or more tensile. The higher or longer the temperature excursion, the more shift in stress. This technique of annealing can be used to “tune” the desired membrane stress from compressive to the final desired tensile stress value. Thus, if the membrane buckles due to compressive stress, annealing can be used to reduce stress and flatten out the membrane mirror.
[0028] Film stresses from fabrication are normally not very low, e.g. silicon nitride films can typically have large stresses, i.e. hundreds of MPa. Thus, silicon nitride membrane mirror stress can be decreased by starting with a relatively high tensile stress nitride film e.g. ˜100 MPa, and depositing a compressive stress reflective oxide, to yield a net low tensile membrane. Through very careful process control, low stress silicon nitride films can be made; even silicon nitride films can now be fabricated with low stress <50 MPa, but with lower process yield. Polymer membrane stresses are usually low.
[0029] Again, referring to FIG. 2 , positioned in close proximity to the top surface 204 of the membrane 202 is a transparent conductor 213 comprised of an optically flat window 214 , transparent or substantially transparent in the appropriate wavelength region, having a transparent conductive film 212 deposited on the bottom surface. In at least one embodiment, the transparent conductor 212 is a Transcon™ film. This transparent conductor 212 is typically a low-loss conductor demonstrating absorption of 0.2-1% at 1.55 micron wavelength, depending on deposition process. As such, the Transcon™ film 212 may operate in an environment wherein the optical power density is on the order of ˜20 kW/cm 3 . A metallic lead 215 electrically connects the transparent conductor 212 to a voltage source (not shown).
[0030] The front and/or back surfaces of the window 214 are coated with anti-reflective (“AR”) coatings 216 . The AR coatings 216 help to ensure that the wavelength energy incident on the DM 200 is transmitted through the window 214 to the membrane 202 , and that energy is not reflected back in the direction of propagation at the front and/or back surfaces of the window 214 . At least one of the two surfaces of the window 214 is AR-coated 216 . In at least one embodiment, the back surface of the window 214 is coated with AR-coating 216 on the very bottom, being, exposed to a low-pressure environment on the bottom side 208 , and next to the transparent conductor film 212 on the topside. In another embodiment, the AR-coating can be embedded in the middle between the window 214 and the transparent conductor film 212 .
[0031] The gap “d 2 ” between membrane 202 and the transparent conductor 213 is small, which is to say on the order of 10-50 μm. In at least one embodiment, a 10 μm spacing, may be made with bead or fiber spacers (e.g. glass), by depositing film material(s) 10 μm thick, by etching, a 10 μm dip into the active area of the transparent conductor 213 , or physically holding the conductor with appropriate micro-positioners and/or fixturings at 10 μm from the membrane 202 .
[0032] FIG. 2 depicts an embodiment of the present invention which does not include a thick ring or substrate supporting the membrane. FIGS. 3 and 4 illustrate embodiments in which the membrane is formed of a preselected material composition and is supported by a surrounding ring or substrate of sufficient thickness to support the membrane during the fabrication process. As will be described below in greater detail, one surface of the membrane is flush with a surface of the thick supporting ring or substance. The other surface of the membrane is in a cavity more than at least hundreds of microns deeper than the surface of the thick supporting ring or substrate. A thin gap may be made by physical holding the conductor (or actuator) with appropriate micropositioners and/or fixturings at 10-50 μm from the membrane. However, this method is difficult to mass-produce with such a deep cavity.
[0033] Referring to FIG. 3 , another embodiment of a compact, high-speed wavefront corrector or DM 300 is illustrated in cross-section. The DM 300 includes a membrane support ring 302 , which by way of example, may be in the form of a silicon wafer; however, other suitable materials configurations may also be used without departing from the scope of the invention. The support ring is generally annular in configuration and includes an upper surface 304 , a lower surface 306 and an aperture 308 which extends between the upper and the lower surfaces. A deformable membrane assembly 310 is disposed along the lower surface 306 of the support ring and includes a thin membrane or organic film 312 which may be of any suitable material(s), by way of example, silicon or silicon nitride, as hereinabove described. One side of the membrane is coated with a first conductive layer 314 . A second conductive layer 316 is applied to the upper surface 304 of the support ring 302 and extends across the aperture 308 and in contact with the other side of the membrane. A reflective coating or layer 318 is deposited on the second conductive layer 316 and also extends across aperture 308 . The deformable membrane assembly and the support ring are positioned on spacers 320 which may be in the form of glass beads or fibers and are of a preselected thickness which may be varied to control the spacing t between the membrane assembly and a plurality of actuators 322 mounted on direct drive backplane 324 in a similar fashion as described above with respect to the embodiment of FIG. 2 .
[0034] A unique transparent conductor assembly design 326 is depicted which has the advantage of tailoring of very small membrane-to-transparent conductor gap 327 , is amenable to mass production, and is easy to assemble. Because light must pass through the transparent conductor to correct for wavefront error, the transparent conductor assembly must be in the form of an optical flat 328 several mm thick. The area of the optical flat is larger than that of the cavity 327 so that the flat can be placed on top of the membrane supporting structure 302 . An inset piece 330 , which is smaller in area than the cavity, is bonded preferably optically or with optical adhesive. The inset piece is positioned immediately adjacent to and against the thick flat and is also an optical flat comprising a conductive film 332 and an antireflective coating 334 . The film may be made of a suitable conductive material, by way of example, Transcon™ The thickness of the inset is made to be nominally 10-50 μm thinner than the thickness of the supporting structure. Alternatively, this gap can also be obtained by etching out an inset into a thick optical flat, for example by deep reactive ion etching of SiO 2 (DRIE). To provide electrical access for biasing the transparent conductor, a thin layer of metal e.g., gold, 336 , is deposited along the side of the complete transparent conductor. The metal must be in contact with the conductive film on the inset piece. Good electrical continuity along the side of transparent conductor is established by sufficiently rounding the edge(s) of the inset piece in the 10-500 nm rms roughness, depending on the thickness of the metal used: as shown in FIG. 3( a ). To further ensure continuity, a small amount of adhesive, e.g., optical adhesive is applied at the intersecting corner between the inset piece and the large optical flat. An antireflective coating 338 is deposited on the surface 340 of the optical flat 328 .
[0035] In operation, the transparent conductor assembly can be simply placed on top of the membrane supporting structure for a pre-determined gap 327 . If a higher gap is desired, glass bead/fiber spacers may be added to adjust the gap. The dimensional requirements of the membrane-to-transparent conductor gap may be relaxed, since a larger bias voltage provides the same membrane response when the gap is small. Furthermore, to allow gas to move faster in and out of the membrane-to-transparent conductor gap during membrane motion, channels or evacuation paths can be etched into various locations on the transparent-conductor surface or the supporting ring 302 .
[0036] Referring now to FIG. 4 , yet another embodiment of a compact, high-speed DM 400 is illustrated in cross-section. The DM 400 includes a membrane support member 402 which may be formed of any suitable material, such as steel or stainless steel. The support member is generally ring-shaped and includes an upper surface 404 , a lower surface 405 , an inner surface 406 defining, an aperture 407 and an outer surface 408 . A deformable membrane assembly 410 is disposed along the lower surface 405 and across the aperture 407 of the support member and includes a thin membrane or organic film 412 as described above. However, in the embodiment of FIG. 4 , the membrane may be formed of a suitable polymer material, which, by way of example and not of limitation, may include polymide membrane materials possessing physical and elastic properties similar to the properties of LaRC™-CP1 or LaRC™-CP2 polymides (trademarks of NASA Langley Research Center) set forth below:
[0000]
TABLE 1
CP1
CP2
Tensile Strenth
14.5 ksi
17 ksi
Tensile Modulus
315 ksi
420 ksi
[0037] Both sides of the membrane are coated with a conductive layer 414 , 416 ; the conductive layer, 416 being arranged to fit inside the aperture 407 and in contact with the inner surface 406 of the support member 402 . A reflective coating 418 is deposited on conductive layer 416 and is likewise adapted to fit inside aperture 407 and in contact with the inner surface 406 of the support member. The deformable membrane assembly and support ring are positioned on spacers 420 which may be in the form of glass beads or fibers and are of a preselected thickness which may be varied to control the spacing t between the membrane assembly and a plurality of actuators 422 mounted on direct drive backplane 424 . The support member may be severed to the membrane assembly by means of a suitable adhesive 425 which is inserted into slot or recess 426 formed in the lower surface 405 of the support members.
[0038] A transparent conductor assembly 428 similar in construction and operation to the transparent conductor assembly of the embodiment of FIG. 3 is positioned on to upper surface 404 of the support member 402 . The transparent conductor assembly is in the form of an optical flat 430 having an area which is larger than that of the aperture so that the flat can be placed on top of the membrane supporting, structure 402 . An inset piece 432 which is smaller in area than the aperture, is bonded preferably optically or with optical adhesive. The inset piece in the restrained state positioned immediately adjacent to and against the thick flat is also an optical flat and comprises a conductive film 434 and an antireflective coating 436 . As in the embodiment of FIG. 3 , the film may be made of a suitable conductive material, by way of example. Transcon™, and the thickness of the inset is made to be nominally 10-50 μm thinner than the thickness of the supporting, structure 402 .
[0039] To provide electrical access for baising the transparent conductor, a thin layer of metal e.g. gold, 438 is deposited along the side of the complete transparent conductor assembly. The metal must be in contact with the conductive film on the inset piece. To further ensure continuity, a small amount of adhesive, e.g., optical adhesive, is applied at the intersecting corner between the inset piece and the large optical flat. An antireflective coating 440 is deposited on the surface 340 of the optical flat 328 . In operation, the transparent conductor can be simply placed on top of the membrane supporting structure for a pre-determined gap 442 . If a higher gap is desired, glass bead/fiber spacers may be added to adjust the gap. The dimensional requirements of the membrane-to-transparent conductor gap may be relaxed, since a larger bias voltage provides the same membrane response when the gap is small. Furthermore, to allow gas to move faster in and out of the membrane-to-transparent conductor gap during membrane motion, channels or evacuation paths can be etched into various locations on the transparent conductor surface or support member 402 .
[0040] In the embodiment of FIG. 2 , the pitch, i.e., the spacing “w 1 ” between the same edge of adjacent actuators (e.g. actuators 220 and 222 ), is less than approximately 1.0 mm, and as low as e.g. 20 μm. In this way, greater than 128 actuators may be used in a DM device 200 while still reducing the overall optical bench size and enabling a high spatial frequency (f s =(2*actuator pitch) −1 >0.5 mm −1 ), as compared to prior art devices. Further, actuator coupling is acceptably low. With for example 1027 actuators spaced approximately 0.5 mm apart, a beam size of 18 mm and a spatial frequency of f s =1 mm −1 can be achieved.
[0041] The plurality of electrostatic actuators 218 is electrically connected to one or more metal leads 224 for providing a voltage to each actuator individually or collectively. Metal leads 224 are connected to a voltage source (not shown), which may or may not be the same voltage source as that used to provide a voltage to the transparent conductor 212 . Both the metal leads 224 and the plurality of electrostatic actuators 218 are in contact with a planarized, direct drive backplane 226 having a surface roughness typically of <15 nm.
[0042] The plurality of electrostatic actuators 218 are positioned in close proximity to the bottom surface 206 of the membrane 202 . The electrostatic actuators 218 are structured and arranged such that the gap “d 3 ” between membrane 202 and the electrostatic actuators 218 is small, which is to say on the order of 10-30 μm. In at least one embodiment, a 10 μm spacing may be made with bead or fiber spacers (e.g. glass), by depositing film material(s) 10 μm thick, by etching a 10 μm step into the active area of the actuators 218 , or by physically holding the actuator with appropriate micro-positioners and/or fixturings (not shown) at 10 μm from the membrane 202 . Furthermore, to allow gas to move faster in and out of the membrane-to-actuator gap during membrane motion, channels or evacuation paths can be etched into various locations on the actuator substrate.
[0043] The operation of a compact, high-speed, membrane DM 501 is graphically depicted in FIGS. 5 and 6 . As shown in FIG. 5 , voltage differentials are a key operational parameter. In operation, the average actuator voltage, <V i > may be less than, equal to, or greater than the transparent conductor bias voltage, V o . The transparent conductor bias voltage V o and the actuator voltages V i determine the sign (+/−) and magnitude of the voltage differential for each actuator. Uniform deflection in an upward direction, as represented for example by arrows 500 and 502 in FIG. 5 , occurs when <V i ><V o . Alternatively, uniform deflection in a downward direction (e.g. arrows 504 and 506 ) occurs when <V i >>V 0 . Of note, although FIG. 5 depicts a fairly uniform parabolic deformation of a membrane, it can be appreciated by those skilled in the art that non-uniform deformation may also be induced by applying different voltages to the actuators, consistent with the aberrations and/or deformations of the incoming wavefront. In this discussion d 5 and d 6 in FIG. 5 are assumed to have approximately the same value; however, d 5 and d 6 can take different values, in which case the bias voltage V o would be scaled appropriately to a higher or lower value, relative to <V i >.
[0044] It can be appreciated that when V i =V o , the static shape of membrane 508 remains substantially flat (i.e. no parabolic curvature). As such, additional optics are not required to remove spherical wavefront distortion. Furthermore, the gap “d 5 ” between membrane 508 and the array of actuators 512 can be reduced to 10-30 μm. The control voltage in an electrostatically actuated device is proportional to the gap (e.g. d 5 ), therefore, the deformable mirror 501 of the present disclosure may operate at about 25-75% of the voltage of a conventional bulk micromachined membrane mirror having a membrane-to-actuator gap on the order of ˜40 μm.
[0045] Referring now to FIG. 6 , a flow chart 600 of the operation of a deformable mirror (e.g. mirror 501 ) is presented. As shown, a wavefront having a variety of distortional aberrations is received by the mirror, block 602 . In order to maximize the optical properties of the wavefront, the mirror must compensate for these distortions/aberrations. Consequently, a bias voltage is applied to the transparent conductor, block 604 . Simultaneously, one or more voltages are applied to one or more of the plurality of electrostatic actuators, block 606 . It should be noted that the same voltage value. V o , need not be applied to each actuator, depending on the desired deformation or curvature of the deformable mirror.
[0046] As a result of transmitting different voltages to the transparent conductor and each selected actuator, voltage differential(s) is established between the bias voltage applied to the transparent conductor and the actuator voltage, and electrostatic forces act upon the membrane consistent with the voltage differential(s). Consequently, the membrane deforms, block 610 .
[0047] It may be necessary for a control system of the DM to adjust the membrane deformation by modifying the voltage differential(s), block 612 , in order to achieve the optimal optical performance of the mirror. Depending on the duration(s) of the received wavefront(s) a feedback mechanism 616 may be used to further adjust the mirror and improve optical performance.
[0048] A method is provided to increase the speed at which the membrane arrives at a given position, by a kick-and-hold technique. If the membrane has a high restoring force (high residual stress), the speed at which the membrane moves from position 1 to position 2 is fast. If the membrane has a low restoring force (low residual stress), the speed at which the membrane moves from position 1 to position 2 is slow. The membrane can be made to move faster from position 1 to position 2 by “kicking” the membrane to a voltage higher than the voltage for position 2, then quickly e.g. microseconds later, resetting the voltage to a “holding” voltage which corresponds to position 2. The membrane, however, cannot be made to move at a frequency much beyond its natural frequency.
[0049] With the compact, high-speed, membrane DM of the present disclosure it is possible to achieve a mechanical resonance frequency of greater than several kHz, a spatial frequency of f s >0.5 mm −1 , and a frame rate in excess of 20 kHz. The operating voltage of the system described above is typically less than ˜300 V for an optical phase throw of 6 microns, and preferably less than 100 V. Further, the DM of the present disclosure achieves large stroke at high spatial frequency while maintaining long-term calibration stability. The DM may be employed with a variety of adaptive optics systems and subsystems needed for applications such as free-space laser communications and high resolution imaging on a mobile platform.
[0050] Changes may be made in the above methods, devices and structures without departing from the scope hereof. It should thus be noted that the matter contained in the above description and/or shown in the accompanying drawings should be interpreted as illustrative and not in a limiting sense. The following claims are intended to cover all generic and specific features described herein, as well as all statements of the scope of the present method, device and structure, which, as a matter of language, might be said to fall therebetween. | Provided is a compact, high-speed deformable mirror for use with an adaptive optic. The mirror or wavefront correction device corrects and/or compensates for wavefront aberrations present in a wavefront received by the optics. The mirror includes a deformable membrane which may be made of a semiconductive, metallic or insulating material. Positioned in close proximity to a front surface of the membrane is a transparent conductor, which may be covered by a window having an anti-reflective coating. A plurality of electrostatic actuators is located in close proximity to a back surface of the membrane, the conductor and actuators separated by a gap of approximately 10 μm. In operation, a bias voltage is applied to the transparent conductor and an actuator voltage is applied to the plurality of actuators. The resultant voltage differential across the membrane defines the amount of membrane deformation, which in turn compensates for distortions in a subsequently reflected wavefront. | 6 |
BACKGROUND OF INVENTION
[0001] 1. Field of the Invention
[0002] This invention is for multiple safety valves for location within an oil or gas well that can be activated to open or close and thus prevent, or permit upward flow of fluids within the well for example in case of an emergency.
[0003] 2. Description of Related Art
[0004] Downhole safety valves are known that include a housing, a flapper valve and a remotely controlled actuator for closing the normally open valve in case of an emergency. See for example U.S. Pat. No. 7,392,849. Also serially arranged valves in a downhole tool are also known. Examples of such are shown in U.S. Pat. Nos. 6,394,187; 7,673,689; 4,846,281; 4,605,070; and 6,152,229. These valves are complicated in design and are not compact as is critical in the art. Furthermore the internal flow passage for the fluids are not of a single diameter and many contain obstruction shoulders or changes in diameter that result in turbulent flow or pressure drops.
[0005] Threaded joints are in common use in hydrocarbon producing wells. During design qualification of subsurface safety valves, a body joint must be designed qualified and verified which is an expensive process, because of the consequences of a leak in a valve of this type. Typical solutions would be to provide valves with two body joints and a pup joint between which adds two additional body joints. The present invention reduces the number of body joints in an integral valve to four or five and utilizes the same body joint.
BRIEF SUMMARY OF THE INVENTION
[0006] The invention disclosed and claimed in this application is for subsurface multiple stage safety valves that are highly reliable, compact, simple to manufacture and include at least two complete, separately functioning safety valves. In accordance with another aspect of the invention, dual control lines are provided which allows for individual operation of each safety valve. This allows the operator the option of operating one valve and keeping the other as a stand-by or operating both valves simultaneously. The principles of the invention can be applied to pressure equalizing or non-pressure equalizing closing systems. Due to the internal design of the valve, the internal flow path is substantially of uniform diameter thus eliminating turbulence and pressure drops due to internal obstructions and irregularities. Furthermore the exterior diameter of the tool is substantially constant. The tool includes a minimum of body joints which increases the reliability of the tool and simplifies construction.
[0007] Another advantage of the valve is the reduction of body joints necessary for its construction. Reducing the number of body joints reduces potential leak paths of hydrocarbons from the inside. Fewer joints also reduces the cost of the body joint.
[0008] Another embodiment of the present invention is to operate both valves with a single control line, which controls the sequence of openings and closures.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S)
[0009] FIG. 1 is a longitudinal sectional view of an embodiment of the invention.
[0010] FIGS. 2 a and 2 b are cross sectional views of an embodiment of the multiple stage safety valve in the closed position.
[0011] FIGS. 3 a and 3 b are cross sectional views of an embodiment of the multiple stage safety valve in the open position.
[0012] FIGS. 4 and 5 are cross sectional views of an example of a piston operated sleeve.
[0013] FIG. 6 is a cross sectional view of the safety valve having a single surface control line.
[0014] FIG. 7 is a view similar to FIG. 6 showing a flow restrictor in the control line branch going to the first valve.
[0015] FIG. 8 is a cross-sectional view of a second embodiment of the invention.
DETAILED DESCRIPTION OF THE INVENTION
[0016] Initially, in order to better understand the invention, the prior art will be discussed. Currently in order to provide redundancy, two valves are simply joined together by a pup joint. The upper valve is connected to production tubing by a threaded connection and the lower valve is connected to lower production tubing by a threaded connection. This results in six body joints. As discussed above these body joints increase the likelihood of leak passages and increase the cost of fabrication.
[0017] Referring to FIG. 1 , an embodiment of the present invention is illustrated. The integral multiple stage safety valve includes five tubular sections 11 , 12 , 13 , 14 and 15 connected to each other by any suitable known methods such as internal and external threads. Upper connection body 11 may be connected to any tubular to be placed within the well. A first spring housing 12 is connected at one end to the upper connection body and at the other end to an integral chamber housing 13 which interconnects the two separate safety valves 60 and 70 as shown in FIGS. 2 a and 2 b according to an embodiment of the invention. Housing 13 includes an interior flow path 57 of substantially constant diameter and generally equal to the interior diameter of sleeve 19 . Second spring housing 14 is connected to a reduced diameter portion 52 of the integral chamber housing 13 by threads as an example. Lower connection body 15 is attached by any known manner to a reduced diameter portion 39 of second spring housing 14 at one end and may be connected to a tubular at its lower end 63 . This design results in four body joints.
[0018] As shown in FIGS. 4 and 5 , each safety valve includes a piston 18 , a sleeve 19 with an enlarged connection portion 34 , a flapper valve element 33 pivotably connected at 32 to the spring housing, a coil spring 38 that biases the flapper valve element against a valve seat 31 and a coil spring 20 that surrounds sleeve 19 .
[0019] As shown in FIG. 4 , a conventional mechanism for operating each safety valve includes a piston 18 having a seal 55 on its outer surface. Piston 18 at its lower end is received by an enlarged connection portion of sleeve 19 . Spring 20 abuts a shoulder 56 on the sleeve 19 and is captured at its other end within spring housing 12 as shown at 61 in FIG. 5 .
[0020] Pressurized hydraulic fluid may be introduced above piston 18 at inlets 51 by separate conduits that extend to the surface. Fluid introduced above piston 18 will cause piston 18 to move downwardly as shown in FIG. 1 , while compressing spring 20 as shown in FIG. 3 a . The lower end of sleeve 19 will push open flapper valve 33 . Conversely, a decrease in the pressure will cause sleeve 19 to move upwardly by the force of the compressed spring which will cause flapper valve 33 to close thereby preventing any upward flow of fluid through the central passageway 16 of the safety valve. As discussed above safety valves 60 , 70 may be independently operated by providing separate hydraulic lines for inlets 51 .
[0021] FIG. 5 illustrates an example of a typical flapper valve that may be utilized with the invention. Lower portion 39 of spring housings 12 and 14 are provided with a valve seat 31 . Flapper valve members 33 are pivotably connected at one side to the spring housings 12 and 14 . The pivot 32 includes a coil spring 38 or the like which biases the valve member 33 against valve seat 31 as is known in the art.
[0022] As shown in FIG. 6 , both valves may be activated by a single control line 80 that extends to the surface. A branch line 83 may extend to the inlet 51 of the upper valve 60 while line 80 connects to inlet 51 of lower valve 70 . A flow restrictor 82 may be located in either branch line 83 or in flow line 80 downstream of branch line 83 as shown in FIG. 7 and FIG. 6 respectively. The positioning of flow restrictor 82 will delay opening of the valve as pressure is applied through control line 80 . In the configuration shown in FIG. 6 , valve 60 will open first followed by valve 70 and in the configuration shown in FIG. 7 valve 70 will open first followed by valve 60 .
[0023] As pressure in the control line is reduced, the valve having the flow restrictor in its control line will close second while the other will close first.
[0024] FIG. 8 illustrates a second embodiment of the invention which includes two independent safety valves similar to those disclosed in FIG. 1 Each safety valve may include an actuator piston, a flow sleeve, a flapper valve element and a coil spring.
[0025] In this embodiment, the safety valve includes six tubular sections 111 , 112 , 113 , 116 , 117 and 118 . First tubular section 111 has an upper portion which may be threadably connected to production tubing in a known manner.
[0026] The lower portion of first tubular member includes a piston chamber in which piston 136 is received. Fluid under pressure is introduced into the piston chamber via an inlet 127 . Piston 112 acts on a flow sleeve 129 to open flapper valve 115 in the manner discussed above.
[0027] The second tubular section 112 is connected to tublar section 111 at a threaded joint 120 . A third tubular section 113 is connected to second tubular section 112 at a threaded joint 121 .
[0028] A fourth tubular section 116 also has a piston chamber in which is mounted a piston 126 which is adapted to move flow sleeve 131 which will open flapper valve 125 in the same manner as discussed above. A fifth tubular section 117 carries flow sleeve 131 and spring 132 and is connected to the fourth tubular section 116 by a threaded joint as shown it 123 . Hydraulic lines 127 and 114 are connected to a source of hydraulic fluid under pressure at the well head.
[0029] A sixth tubular member 118 is connected to the fifth tubular section 117 at a threaded joint shown at 124 . The lower portion of the sixth tubular member includes a threaded female connector adapted to receive a threaded portion of a production tubular.
[0030] Third tubular member 113 and fourth tubular member 116 in this embodiment form a chamber housing that consists of two tubular members.
[0031] The tubular members are connected together in a similar manner at 120 , 121 , 122 , 123 and 124 . Each joint includes a female threaded portion of the tubular member at its upper portion and a male threaded member at its lower end which is threadably connected to the female portion of the tubular member below it.
[0032] The outside diameter of the tubular members in the embodiments of FIGS. 1 and 8 are substantially the same as are the diameters of the inner flow passages. This embodiment results in five tubular joints.
[0033] Although the present invention has been described with respect to specific details, it is not intended that such details should be regarded as limitations on the scope of the invention, except to the extent that they are included in the accompanying claims. | An integral multistage safety valve is designed to provide a second level of protection should a first stage fail. The valve may be used in oil and/or gas wells. The interior portion of the multiphase safety valve is designed so as to reduce turbulence and pressure loss through the valve when the valve is in an open position. The valves may be independently operable, or operable with a single control line. The multi-stage valve reduces the number of body joints required to construct two identical valves thereby reducing cost and potential leak paths and increasing reliability of the system. | 4 |
BACKGROUND
[0001] The invention relates to an arrangement for adjusting the angle of rotation of a camshaft relative to a crankshaft of an internal combustion engine.
[0002] In internal combustion engines, the crankshaft drives one or more camshafts via a primary drive, which may be provided as a toothed belt, for example. For this purpose, a camshaft timing gear is mounted on each camshaft, by which the primary drive drives the camshaft. Here, at all times a transmission of the angle of rotation of the camshaft occurs, in which a 720° angle of rotation of the crankshaft φ K is transmitted into a 360° angle of rotation of the camshaft φ N . Therefore, through this coupling the two angles of rotation are constant in reference to one another. In most applications, this fixed coupling of crankshaft and camshaft results in a ratio of
φ N ( t ) φ K ( t ) = 1 2
[0003] However, the operational characteristics of an internal combustion engine can be optimized, particularly with regard of fuel consumption, exhaust emission, and running performance, when the system of camshaft and crankshaft, coupled via the primary drive, can be modified.
[0004] DE 100 38 354 A1 discloses an arrangement for adjusting the angle of rotation of a camshaft relative to a crankshaft through the use of a wobble plate mechanism. Here, a second drive additionally acts on the camshaft via the wobble plate mechanism, which is arranged between the camshaft timing gear and the camshaft. This causes the camshaft to be adjustable in reference to the crankshaft.
SUMMARY
[0005] The objective of the invention is to provide a simple and cost effective arrangement for adjusting the angle of rotation of the camshaft relative to the crankshaft.
[0006] This objective is met using the features according to the invention. Here, such an arrangement is constructed in a modular fashion, so that the various tasks of such an arrangement are distributed to several control devices, which again may be arranged independent from one another.
[0007] The advantage of the invention lies in such a construction being very cost effective because functions of other control devices can be used as well. An additional advantage of the invention is the fact that individual control devices of the arrangement can be reduced in size. Such an arrangement also allows the distribution of the tasks to the module most suitable therefor, depending on certain mechanical and/or electrical parameters, such as e.g., capacity, current, and voltage, in particular to control devices, which are most appropriate to the requirements.
[0008] Advantageous further developments are also provided. Preferably, the target value of the motor control can be predetermined. It is also advantageous, if the target value refers to a value of an angle, a rotational speed, power, or rotational moment, which are particularly easy to measure and adjust.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] The invention is explained in further detail using an exemplary embodiments as illustrated in the figures, which show:
[0010] FIG. 1 is a schematic view showing an arrangement with a predetermined target angle according to the invention;
[0011] FIG. 2 is a schematic view showing an arrangement with a predetermined target rotational speed according to the invention; and
[0012] FIG. 3 is a schematic view showing an arrangement with a predetermined power and/or target moment.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0013] FIG. 1 shows an arrangement, in which the target value for the control device 7 of the motor control device 1 is predetermined. Here, it relates to a target angle, which is to be adjusted as a predetermined rotation angle of the crankshaft 6 relative to the camshaft 5 . This changes the angle of rotation of the two shafts 5 , 6 relative to one another. The motor control device 1 , predetermining said target angle, essentially controls the internal combustion engine, which drives the crankshaft 6 . This target angle serves as a reference value for the second control device 2 , which simultaneously collects the measurements of sensors 8 a , 8 b , collecting the actual value of the dimension to be adjusted. Here, for example, sensors 8 a , 8 b can measure the position of the camshaft and the crankshaft 5 , 6 . Measuring the position of the camshaft and the crankshaft 5 , 6 allows the determination of the angle of rotation in reference to one another. This angle of rotation can be modified by the adjuster 4 . In the exemplary embodiment, the value of the target angle is forwarded from the motor control device 1 to a second control device 2 . The second control device 2 controls an electric motor 3 , which operates the adjuster 4 . In the exemplary embodiment, the second control device 2 for the electric motor 3 comprises the final stage for adjusting the electric motor 3 and the adjustment of the position of the arrangement. The arrangement shown represents a circuit having a control device 7 and a control path 9 , with the control path comprising the camshaft and the crankshaft 5 , 6 , with the angle of rotation relative to one another being modified and the control device being assembled with the following components:
a target value adjuster composed from several control devices 1 , 2 , with the target value being generated by the motor control 1 , transferred to the control device 2 , in which the switching mechanism for adjusting the target value is located. a measuring device, in the exemplary embodiment formed by the sensors 8 a , 8 b at the camshaft and/or crankshaft and comprising sensors, alternately or additionally, for recognizing the position of the electric motor and/or the adjuster. a comparator comparing the target value to the actual value, with this function in the exemplary embodiment also being integrated in the control device 2 , and an adjustment member adjusting the angle of rotation of the camshaft, which in the exemplary embodiment is formed by the electric motor 3 and the adjustor 4 .
[0018] FIG. 2 also shows an arrangement, in which the target value for the control device 7 is predetermined by the motor control 1 . However, here the target angle is not determined and forwarded directly, rather the target rotational speed for the electric motor 3 is determined and forwarded by the motor control 1 of the internal combustion engine, by which the desired angle of the rotation of the crankshaft relative to the camshaft can be adjusted.
[0019] This target rotational speed serves as a reference value for the control device 2 , which can simultaneously process the measurements of the sensors 8 a , 8 b representing the actual value of the control variable of the angle of rotation. For example, said sensors 8 a , 8 b can measure the position of the camshaft and the crankshaft 5 , 6 in the control path 9 . Alternately or additionally, the rotational speed of the electric motor 3 at a certain time can be measured, and then compared in the control device 2 to a target value. The control device 2 for the electric motor 3 also includes the final stage for controlling the electric motor 3 . However, the control of the position of the arrangement is performed by the motor control 1 , which varies the target rotational speed accordingly until the desired state of the camshaft relative to the crankshaft has been achieved. However, this adjustment of the position can also be realized in a different arrangement. Certainly, the control device 2 may also perform other functions. The arrangement shown represents a circuit with a control device 7 and a control path 9 , with the control path comprising the camshaft and the crankshaft 5 , 6 , and their angle of rotation relative to one another being modified, and the control device being assembled from the following components:
a target value adjuster assembled from several control devices 1 , 2 , with the target value being generated by the motor control 1 , which is transferred to the control device 2 , comprising the final stage for the electric motor. Here, the position adjustment can be provided either in the motor control 1 or in the control device 2 . a measuring device, in the exemplary embodiment formed at the electric motor 3 in the form of a tachometer and/or by the sensors 8 a and 8 b according to the previous exemplary embodiment. a comparator comparing the actual value to the target value, with the function also being integrated in the control device 2 in the exemplary embodiment. and the actuator controlling the angle of rotation of the camshaft, which in the exemplary embodiment comprises the electric motor 3 and the adjustment device 4 .
[0024] The individual electric and electronic functions and tasks are performed at different locations in the arrangement. In particular, other control devices or gadgets handle partial tasks and/or partial functions of the arrangement. Similarly, it is not mandatory for the above-mentioned components to be located in the same housing. The control of the target rotational speed of the adjuster 4 is equivalent to the above-described control of the target rotational speed of the electric motor 3 , because the rotational speed of the adjuster 4 is directly dependent on the rotational speed of the electric motor 3 .
[0025] FIG. 3 shows an arrangement, in which the target value for the control device 7 is predetermined by the motor control device 1 for the control device 2 in the form of a target current or a target moment for the electric motor 3 . The target current and/or target moment indirectly determines and/or modifies the angle of rotation of the camshaft relative to the crankshaft 6 , 7 . The amount of target current and moment used is predetermined by the motor control device. The target value of the motor control 1 is forwarded by the control device 2 . Here, the value affects the operational parameters for the electric motor 3 , which again more or less directly drives the adjuster 4 . Here too, in this exemplary embodiment, the adjuster 4 is provided with a wobble plate mechanism, which is connected to the camshaft 5 , driven by the crankshaft 6 . In order to determine if the target value in the control device has been reached, actual real values in the electric motor 3 and also in the adjuster are collected and provided for the control device as control values for variance comparison.
[0026] Here, too, the motor control device 1 determines the target current or the target moment, i.e., essentially controls the internal combustion engine, which drives the camshaft 6 . The target value of the current and/or the moment serves as a reference value for the control device 2 , which simultaneously collects the measurements at the electric motor 3 and/or at the adjuster 4 , representing the actual comparison value in reference to the target value. Here, the adjustment path comprises the camshaft and the crankshaft 5 , 6 , with their relative angle of rotation with respect to one another being modified by way of the modifying operational current of the electric motor and, thus, also of the torque and/or the rotational speed of the electric motor and/or the adjuster being modified. The corresponding control device is assembled from the following components:
a target value adjuster, with the target value being generated and updated by the motor control 1 and the target value being transferred to the control device 2 , containing the switch, by which this target value can be adjusted. a measuring device, in the exemplary embodiment measuring a current, a rotational speed, or a torque at the electric motor or at the adjuster, which provides an actual value for the control device 2 for a comparison to the target value. a comparator, comparing the actual value to the target value, with this function in the exemplary embodiment being integrated in the control device 2 . and the actuator, influencing the angle of rotation of the camshaft 5 and being formed by the electric motor 3 and the adjuster 4 in the exemplary embodiment.
[0031] The individual electric and electronic functions and tasks are rformed at different positions in the arrangement. In particular, other control ices or arrangements cover partial tasks and/or partial functions of the rangement. Similarly, it is not necessary for the above-mentioned components to located in the same housing, rather they can be installed and/or integrated in ious devices, which are provided with additional functions.
[0032] All the exemplary embodiments can be combined in an arbitrary nner, it is only important that the control device has a modular structure.
List of Reference Characters
[0000]
1 Motor control
2 Control device
3 Electric motor
4 Adjustor having a swash plate mechanism
5 Camshaft
6 Crankshaft
7 Control device
8 a Sensor
8 b Sensor
9 Control path | An arrangement for adjusting the angle of rotation of a camshaft ( 5 ) relative to a crankshaft is provided. The arrangement requires many components, which partially also require different operational conditions. The new arrangement is structured in a modular fashion, so that the components of the arrangement are no longer arranged inside a common housing, but rather are separately constructed according to their function and/or operational conditions, for example, they are used jointly by other control or adjustment devices. It is particularly advantageous that such arrangements can be produced in a reduced size and in a more cost effective manner and can be used for adjusting the valve play of internal combustion engines. | 5 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] The present application claims priority of Korean Patent Application Number 10-2009-0070925 filed on Jul. 31, 2009, the entire contents of which application is incorporated herein for all purposes by this reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates generally to an air bag cushion for vehicles intended to protect a passenger and, more particularly, to an air bag cushion for a front passenger seat.
[0004] 2. Description of Related Art
[0005] Recently, with the increasing demands on the safety and protection for passengers, the ratio of vehicles equipped with front passenger air bags are on the increase.
[0006] A conventional front passenger air bag may be not helpful, rather dangerous for a child sitting in a front passenger seat. That is because children are usually seated on the front passenger seat using a child restraint system (CRS) and positioned on a side of front edge of the front passenger seat. In this case, the sudden expansive force of an air bag cushion in an initial expansion stage may strike a child's face and cause a neck injury of the child.
[0007] FIG. 1A is a view illustrating the expansion of an air bag cushion for a front passenger seat which was developed recently. The air bag cushion 1 is constructed so that a vertical valley 4 is formed between left and right chambers 2 and 3 (hereinafter, referred to as a ‘vertical two-chamber structure’). The left chamber 2 expands towards the left side of the upper part of the body of a passenger (not shown), the right chamber 3 expands towards the right side of the upper part of the passenger's body, and the upper portion of the valley 4 comes into contact with the passenger's face. Reference numeral 5 denotes an exterior vent hole for discharging gas from the air bag cushion. The air bag cushion 1 is designed such that a child's face comes to rest on the valley 4 , mainly, on a portion around the lower end of the valley 4 in the event of a vehicle collision, thus preventing the child from being injured, unlike a conventional air bag cushion.
[0008] However, the air bag cushion having the vertical two-chamber structure shown in FIG. 1A is complicated in structure. In the process of manufacturing the air bag cushion, operations of sewing two sheets 6 and 7 along their edges as shown in FIG. 1B are frequently required. In this case, remnants 9 may be undesirably left behind outside of the sewing lines 8 . In order to make the appearance good, the sheets 6 and 7 sewn along the edges as shown in FIG. 1B must be turned inside out so that the remnants 9 are not exposed to the outside of the finished air bag cushion. In the case of the vertical two-chamber structure requiring the sewing of several sheets, the sequence of sewing is complicated, so that the structure and manufacture of the air bag cushion are complicated.
[0009] The information disclosed in this Background of the Invention section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.
BRIEF SUMMARY OF THE INVENTION
[0010] Accordingly, the present invention has been made keeping in mind the above problems occurring in the prior art, and the present invention provides for an air bag cushion for vehicles having a vertical two-chamber structure, which is simple in structure.
[0011] The present invention also provides for an air bag cushion for vehicles having a vertical two-chamber structure, which allows symmetric and uniform expansion of two chambers thereof.
[0012] The present invention further provides for an air bag cushion for vehicles having a vertical two-chamber structure, in which a variety of shapes of the valley between the two chambers can be achieved easily.
[0013] In order to accomplish such, the present invention provides an air bag cushion, including a left chamber configured to be expanded towards a left side of an upper part of a body of a passenger, a right chamber configured to be expanded towards a right side of the upper part of the body of the passenger, and at least one connection part formed in front portions of the left and right chambers by sewing facing inner surfaces of the left and right chambers along sewing lines in a shape of closed curve to form a vertical valley which separates the left and right chambers from each other. A through hole is formed in the connection part to permit gas to flow between the left and right chambers.
[0014] The left chamber may include a left outer sheet and a left inner sheet sewn along an edge thereof to the left outer sheet. The right chamber may include a right inner sheet sewn to the left inner sheet at the connection part and a rear end thereof, and a right outer sheet sewn along an edge thereof to the right inner sheet.
[0015] The left chamber may be provided by sewing the left and right inner sheets to each other at the connection part, sewing the left outer sheet and the left inner sheet to each other along edges thereof with the right inner sheet placed between the left outer sheet and the left inner sheet, and turning the left outer sheet inside out.
[0016] The right chamber may be provided by sewing the left and right inner sheets to each other at the connection part, sewing the right outer sheet and the right inner sheet to each other along edges thereof with the left inner sheet placed between the right outer sheet and the right inner sheet, and turning the right outer sheet inside out.
[0017] Further, rear ends of the left and right inner sheets may be sewn vertically and horizontally so that a partition part is provided at rear ends of the left and right chambers to partition the left and right chambers from each other.
[0018] Further, a gap at which the left and right inner sheets are not sewn may be provided between the connection part and the partition part.
[0019] Further, a gas injection part may be provided in the rear ends of the left and right chambers in such a way as to communicate with the chambers, with gas being injected from the inflator to the gas injection part.
[0020] The air bag cushion may further include at least one joining part placed in front of the connection part and provided by sewing the left and right inner sheets to each other along sewing lines in a shape of a closed curve.
[0021] The joining part may be formed to become ripped more easily than the connection part.
[0022] The air bag cushion may further include a tether which passes through the connection part and connects the left and right chambers to each other in a lateral direction of the air bag cushion.
[0023] Further, one end of the tether may be connected to the left outer sheet and the other end may be connected to the right outer sheet.
[0024] The methods and apparatuses of the present invention have other features and advantages which will be apparent from or are set forth in more detail in the accompanying drawings, which are incorporated herein, and the following Detailed Description of the Invention, which together serve to explain certain principles of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0025] FIG. 1A is a view illustrating a conventional air bag cushion.
[0026] FIG. 1B is a view illustrating the process of manufacturing the conventional air bag cushion.
[0027] FIG. 2 is a schematic view illustrating an air bag cushion according to the present invention.
[0028] FIG. 3 is a schematic exploded view illustrating the air bag cushion of FIG. 2 .
[0029] FIGS. 4A to 4F are views illustrating the process of manufacturing the air bag cushion of FIG. 2 in stages.
[0030] FIGS. 5A and 5B are views illustrating the process of finishing the rear end of the air bag cushion of FIG. 2 .
[0031] FIGS. 6A and 6B are schematic views illustrating other air bag cushions according to the present invention.
[0032] FIGS. 7A to 7F are schematic views illustrating other air bag cushions according to the present invention.
[0033] FIGS. 8A to 8C are a plan view, a front view, and a right side view illustrating the air bag cushion manufactured according to the present invention, respectively.
DETAILED DESCRIPTION OF THE INVENTION
[0034] Reference will now be made in detail to various embodiments of the present invention(s), examples of which are illustrated in the accompanying drawings and described below. While the invention(s) will be described in conjunction with exemplary embodiments, it will be understood that present description is not intended to limit the invention(s) to those exemplary embodiments. On the contrary, the invention(s) is/are intended to cover not only the exemplary embodiments, but also various alternatives, modifications, equivalents and other embodiments, which may be included within the spirit and scope of the invention as defined by the appended claims.
[0035] As shown in FIG. 2 , the air bag cushion 10 is constructed so that a vertical valley 18 a is formed on the front portions of left and right chambers 11 and 12 to separate the chambers 11 and 12 from each other. The left and right chambers 11 and 12 are sewn to each other at a connection part 15 and a partition part 16 . A gap 18 b at which both chambers 11 and 12 are not sewn is provided between the connection part 15 and the partition part 16 .
[0036] A gas injection part 19 is provided on the rear ends of the left and right chambers 11 and 12 . A housing 80 for accommodating the air bag cushion 10 and an inflator 70 supported by the housing 80 are installed around the gas injection part 19 . The inflator 70 is mounted outside the air bag cushion 10 and a gas discharge port of the inflator 70 is partially inserted into the cushion 10 . Of course, the inflator 70 may be installed inside the air bag cushion 10 .
[0037] The gas, injected from the inflator 70 to the gas injection part 19 , is supplied to the left and right chambers via the partition part 16 which partitions the left and right chambers at the rear side of the air bag cushion 10 . Reference numeral 17 denotes sewing lines which define the gas injection part 19 . The sewing lines 17 of the gas injection part 19 will be described in detail with reference to FIG. 3 . In this context, it should be understood that the well known retainer ring placed in the air bag cushion 10 for retaining the inflator 70 to the cushion 10 is not shown in FIG. 2 .
[0038] At least one through hole 15 b (see FIG. 3 ) is formed in each connection part 15 to permit air to flow between the left and right chambers 11 and 12 . The gas may be non-uniformly supplied from the gas injection part 19 to the left and right chambers 11 and 12 , and the expansion speed of the chambers 11 and 12 may be different. The through hole 15 b allows the gas to be uniformly dispersed to both chambers 11 and 12 , thus causing the chambers 11 and 12 to uniformly and symmetrically expand.
[0039] Still referring to FIG. 2 , a tether 60 is provided on the front portions of the left and right chambers 11 and 12 and passes through the connection part 15 to connect the left and right chambers 11 and 12 to each other in a direction from the left side of the cushion 10 to the right side thereof.
[0040] The tether 60 functions to hold the shape of the air bag cushion 10 during and after the expansion of the cushion 10 and make the two chambers 11 and 12 expand symmetrically. For example, if the expanding speed of the left chamber 11 is higher than that of the right chamber 12 as a result of non-uniform supply to both chambers 11 and 12 , the tether 60 delays the expansion of the left chamber 11 and make pressurized gas be distributed from the left chamber 11 through the through hole 15 b to the right chamber 12 .
[0041] The construction and components of the air bag cushion 10 will be described with reference to FIGS. 2 and 3 .
[0042] The left chamber 11 is manufactured by sewing a left outer sheet 20 and a left inner sheet 30 along edge sewing lines 13 . The right chamber 12 is manufactured by sewing a right outer sheet 50 and a right inner sheet 40 along edge sewing lines 14 . The left inner sheet 30 and the right inner sheet 40 are sewn at their rear ends 32 and 42 with the connection part 15 .
[0043] At least one through hole 15 b is formed in an area forming the connection part 15 of each of the left and right inner sheets 30 and 40 . When the through hole 15 b is too small, it is insufficient to remove the non-uniform expansive pressure of the left and right chambers 11 and 12 . In contrast, when the through hole 15 b is too large, the external impact bearing force of the cushion 10 may be reduced. Thus, it is preferable that one or several through holes 15 b having a proper size be formed. The left and right inner sheets 30 and 40 may be sewn around the through holes 15 b , in addition to the sewing lines 15 a of the connection part 15 .
[0044] Sewing lines provided at the rear ends 32 and 42 of the left and right inner sheets 30 and 40 define the partition part 16 which is provided on the rear ends of the left and right chambers 11 and 12 to partition them from each other. The gas, which is injected from the inflator 70 to the gas injection part 19 , is divided at the partition part 16 and supplied to the left and right chambers 11 and 12 . The sewing lines of the partition part 16 are formed horizontally as well as vertically. A bolt inserted from the known retainer ring is fastened through a mounting hole 72 so that the inflator 70 is locked to the air bag cushion 10 .
[0045] Meanwhile, as shown in FIG. 3 , the length D of the rear ends 22 and 52 of the left and right outer sheets 20 and 50 is longer than the length d of the rear ends 32 and 42 of the left and right inner sheets 30 and 40 . The reason for this is because openings formed in the rear portions of the chambers 10 and 20 are closed (see FIGS. 5A and 5B ) using the rear ends 32 and 42 and the gas injection part 19 is formed in the openings. A recess 19 a is provided in the rear ends 32 and 42 of the left and right inner sheets 30 and 40 to provide the gas injection part 19 , and inflator holes 71 and mounting holes 72 are formed in the rear ends 22 and 52 of the left and right outer sheets 20 and 50 .
[0046] The method of manufacturing the air bag cushion 10 will be described with reference to the above-mentioned drawings and FIGS. 4A to 4F . FIGS. 4A to 4F are sectional views taken along line A-A of FIG. 3 and illustrating the process of sewing the sheets 20 , 30 , 40 and 50 in sequence.
[0047] As shown in FIGS. 4A and 4B , in the state where the left inner sheet 30 and the right inner sheet 40 face each other, the front portions of the sheets 30 and 40 are sewn along the sewing lines 15 a in the shape of a closed curve, thus forming the connection part 15 . Further, the rear ends of the left and right inner sheets 30 and 40 are sewn, thus forming the partition part 16 (see FIG. 3 ).
[0048] As shown in FIG. 4C , in the state where the left outer sheet 20 is placed to a side of the right inner sheet 40 , the left outer sheet 20 and the left inner sheet 30 are sewn along the edge sewing lines 13 . Next, a pocket formed by the left outer sheet 20 is turned inside out. Thereby, the left chamber 11 having the edge sewing lines 13 therein is obtained as shown in FIG. 4D .
[0049] In the above-mentioned manner, as shown in FIG. 4E , in the state where the right outer sheet 50 is placed to a side of the left outer sheet 20 , the right outer sheet 50 and the right inner sheet 40 are sewn along the edge sewing lines 14 . Next, the right outer sheet 50 is turned inside out. Thereby, the right chamber 12 having the edge sewing lines 14 therein is obtained as shown in FIG. 4F .
[0050] Such a sewing sequence enables the easy sewing of the sheets 20 , 30 , 40 and 50 , in spite of the existence of the connection part 15 . The sequence of sewing the sheets 20 , 30 , 40 and 50 may be changed. For example, the right chamber 12 may be firstly formed by sewing the right inner sheet 40 and the right outer sheet 50 along the sewing lines 14 after placing the left inner sheet 30 between the right inner sheet 40 and the right outer sheet 50 .
[0051] FIGS. 5A and 5B are schematic views illustrating the process of forming the gas injection part 19 using the rear ends 22 and 52 of the left and right outer sheets 20 and 50 . It should be understood that the shape of the air bag cushion shown in the drawings may be different from an actual shape since the drawings are schematically shown.
[0052] Referring to FIGS. 2 , 3 , 5 A and 5 B, after the rear ends 22 and 52 of the left and right outer sheets 20 and 50 are folded from the state of FIG. 4F such that the inflator holes 71 overlap each other, the rear ends 22 and 52 are sewn together with the front ends 21 and 51 of the sheets 20 and 50 along the sewing lines 17 , so that the gas injection part 19 is formed at the rear ends of the left and right chambers 11 and 12 . The gas discharge port of the inflator 70 is inserted through the inflator holes 71 into the gas injection part 19 , and the inflator 70 is coupled to the retainer ring by fastening members which are fitted into the mounting holes 72 .
[0053] Referring to FIGS. 6A and 6B , the connection of the left and right chambers 11 and 12 which is made through the connection part 15 enables the shape of the valley 18 a and the chambers 11 and 12 to be variously changed as necessary. For example, the valley 18 a may be formed from the upper portions of the left and right chambers 11 and 12 to the lower portions thereof as shown in FIG. 6A , or may be formed such that there is a deep valley 18 a in the lower portions of the left and right chambers 11 and 12 as shown in FIG. 6B . All of the above-mentioned shapes of the air bag cushion are useful when it comes to protecting a passenger.
[0054] Referring to FIGS. 7A , 7 C and 7 D, the shape and number of connection parts 101 of the air bag cushions 100 , 120 and 130 according to various embodiments of the present invention and the shape and number of the through holes 102 in an area of the connection part 101 may be changed.
[0055] Further, referring to FIGS. 7B , 7 E and 7 F, the air bag cushions 110 , 140 and 150 according to various embodiments of the present invention may further include a joining part 103 which is placed in front of an associated connection part 101 and made by sewing the left and right inner sheets 30 and 40 together along sewing lines in the shape of a closed curve. The joining part 103 may be sewn using thread which is thinner than that of the connection part 101 or may be sewn more thinly than the connection part 101 . The joining part 103 is provided in front of the connection part 101 and ripped by collision with a passenger, thus absorbing impact and protecting the passenger.
[0056] FIGS. 8A to 8C are drawings illustrating a cushion sample manufactured according to various embodiments of the present invention and seen at several angles. The sample is manufactured to check the manufacturability and convenience of the cushion according to the various embodiments. The rear end corresponding to the gas injection part is not assembled and is omitted from the drawings.
[0057] Meanwhile, according to other embodiments, the rear end and the front end of the cushion may be manufactured using separate sheets and then be sewn to provide a space for the gas injection part. Reference numeral 90 of FIG. 8C denotes an exterior vent hole which functions to reduce the internal pressure of the air bag cushion under given conditions.
[0058] As described above, the present invention provides an air bag cushion having a vertical two-chamber structure, which is simple in structure.
[0059] Further, the present invention provides an air bag cushion, which allows left and right chambers to uniformly expand.
[0060] Furthermore, the present invention provides an air bag cushion having a vertical two-chamber structure, which allows a valley to assume a variety of shapes which can easily be realized.
[0061] For convenience in explanation and accurate definition in the appended claims, the terms “upper” or “lower”, “front” or “rear”, “inside” or “outside”, and etc. are used to describe features of the exemplary embodiments with reference to the positions of such features as displayed in the figures.
[0062] The foregoing descriptions of specific exemplary embodiments of the present invention have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the invention to the precise forms disclosed, and obviously many modifications and variations are possible in light of the above teachings. The exemplary embodiments were chosen and described in order to explain certain principles of the invention and their practical application, to thereby enable others skilled in the art to make and utilize various exemplary embodiments of the present invention, as well as various alternatives and modifications thereof. It is intended that the scope of the invention be defined by the Claims appended hereto and their equivalents. | An air bag cushion for vehicles has a connection part which is formed in front portions of the left and right chambers by sewing the inner surfaces of the left and right chambers along sewing lines in a shape of closed curve to form a vertical valley which separates the left and right chambers from each other. A through hole is formed in the connection part to permit gas to flow between the left and right chambers. The cushion includes a tether which passes through the connection part and connects the left and right chambers to each other in a lateral direction of the cushion. The air bag cushion is simple in structure and is superior in uniform expanding performance of the left and right chambers. | 1 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates generally to papermaking, and relates more specifically to fabrics employed in making press felts on a paper machine, pulp machine fiber cement belts, and corrugated paper board, or box-board. The invention also relates to the monofilament base of fabric optionally with a needled batt which can provide one or more of the following advantages: hydrolysis resistant materials, providing light weight high strength fabrics, having a high permeability, and soft surface with a high coefficient of friction. The present invention also relates to an integrated loop seam integrated with machine direction yarns of the monofilament base which can provide one or more of the following advantages: extremely stable and flexible corrugator fabric, and the ability to provide a non-marking loop seam.
[0003] 2. Discussion of Background Information
[0004] During the papermaking process, a cellulosic fibrous web is formed by depositing a fibrous slurry, that is, an aqueous dispersion of cellulose fibers, onto a moving forming fabric in the forming section of a paper machine. A large amount of water is drained from the slurry through the forming fabric, leaving the cellulosic fibrous web on the surface of the forming fabric.
[0005] The newly formed cellulosic fibrous web proceeds from the forming section to a press section, which includes a series of press nips. The cellulosic fibrous web passes through the press nips supported by a press fabric, or, as is often the case, between two such press fabrics. In the press nips, the cellulosic fibrous web is subjected to compressive forces which squeeze water therefrom, and which adhere the cellulosic fibers in the web to one another to turn the cellulosic fibrous web into a paper sheet. The water is accepted by the press fabric or fabrics and, ideally, does not return to the paper sheet.
[0006] The paper sheet finally proceeds to a dryer section, which includes at least one series of rotatable dryer drums or cylinders, which are internally heated by steam. The newly formed paper sheet is directed in a serpentine path sequentially around each in the series of drums by a dryer fabric, which holds the paper sheet closely against the surfaces of the drums. The heated drums reduce the water content of the paper sheet to a desirable level through evaporation. It should be appreciated that the forming, press and dryer fabrics all take the form of endless loops on the paper machine and function in the manner of conveyors. It should further be appreciated that paper manufacture is a continuous process which proceeds at considerable speeds. That is to say, the fibrous slurry is continuously deposited onto the forming fabric in the forming section, while a newly manufactured paper sheet is continuously wound onto rolls after it exits from the dryer section.
[0007] Contemporary fabrics are produced in a wide variety of styles designed to meet the requirements of the paper machines on which they are installed for the paper grades being manufactured. Generally, they comprise a woven or other type base fabric. Additionally, as in the case of fabrics used in the press section, the press fabrics have one or more base fabrics into which has been needled a batt of fine, nonwoven fibrous material. The base fabrics may be woven from monofilament, plied monofilament, multifilament or plied multifilament yarns, and may be single-layered, multi-layered or laminated. The yarns are typically extruded from any one of the synthetic polymeric resins, such as polyamide and polyester resins, used for this purpose by those of ordinary skill in the paper machine clothing arts.
[0008] The woven base fabrics themselves take many different forms. For example, they may be woven endless, or flat woven and subsequently rendered into endless form with a woven seam. Alternatively, they may be produced by a process commonly known as modified endless weaving, wherein the widthwise edges of the base fabric are provided with seaming loops using the machine-direction (MD) yarns thereof. In this process, the MD yarns weave continuously back-and-forth between the widthwise edges of the fabric, at each edge turning back and forming a seaming loop. A base fabric produced in this fashion is placed into endless form during installation on a paper machine, and for this reason is referred to as an on-machine-seamable fabric. To place such a fabric into endless form, the two widthwise edges are brought together, the seaming loops at the two edges are interdigitated with one another, and a seaming pin or pintle is directed through the passage formed by the interdigitated seaming loops.
[0009] Further, the woven base fabrics may be laminated by placing at least one base fabric within the endless loop formed by another, and by needling a staple fiber batt through these base fabrics to join them to one another as in the case of press fabrics. One or more of these woven base fabrics may be of the on-machine-seamable type. This is now a well known laminated press fabric with a multiple base support structure.
[0010] In any event, the fabrics are in the form of endless loops, or are seamable into such forms, having a specific length, measured longitudinally therearound, and a specific width, measured transversely thereacross.
[0011] Reference is now made more specifically to industrial fabrics used in the manufacture of corrugated paper board, or box-board, on corrugator machines. Such an industrial fabric is used to form corrugator belts. On corrugator machines, corrugator belts support and pull a sheet of liner board and a sheet of paper board which pass over a roll which adds flutes or CD corrugations to the paperboard sheet. Then these at least two paperboard sheets supported by one or more belts are passed first through a heating zone, where an adhesive used to bond the at least two layers of the board together is dried and cured, and then through a cooling zone. Frictional forces between the corrugator belt, specifically the face, or board, side thereof, and the corrugated paper board are primarily responsible for pulling the latter through the machine.
[0012] Corrugator belts should be strong and durable, and should have good dimensional stability under the conditions of tension and high temperature encountered on the machine. The belts must also be comparatively flexible in the longitudinal, or machine, direction, while having sufficient rigidity in the cross-machine direction to enable them to be guided around their endless paths. Traditionally, it has also been desirable for the belts to have porosities sufficient to permit vapor to pass freely therethrough, while being sufficiently incompatible with moisture to avoid the adsorption of condensed vapor which might rewet the surfaces of the corrugated paper product.
[0013] As implied in the preceding paragraph, a corrugator belt takes the form of an endless loop when installed on a corrugator machine. In such form, the corrugator belt has a face, or boardside, which is the outside of the endless loop, and a machine side, which is the inside of the endless loop. Frictional forces between the machine side of the belt and the drive rolls of the corrugator machine move the corrugator belt, while frictional forces between the faceside and the sheet of corrugated board pull the sheet through the machine.
[0014] Corrugator belts are generally flat-woven, multi-layered fabrics, each of which is woven to size or trimmed in the lengthwise and widthwise directions to a length and width appropriate for the corrugator machine on which it is to be installed. The ends of the fabrics are provided with seaming means, so that they may be joined to one another with a pin, pintle, or cable when the corrugator belt is being installed on a corrugator machine.
[0015] On corrugator box-board machines, there is a transformation from sheets of linerboard paper and corrugating medium paper into corrugated box-board. This is achieved by the application of a liquid adhesive to the three sheets of paper and the pressing by one or more corrugator belts, woven or needled or a combination thereof onto a heating zone. In a typical corrugator machine, the heating zone comprises a series of steam-heated plates to dry the adhesive thereby “gluing” the paper assembly together, and the sheet of corrugated board is pulled by the corrugator belt. A plurality of weighted rollers within the endless loop formed by the corrugator belt press the corrugator belt toward the hot plates, so that the corrugator belt may pull the sheet across the hot plates under a selected amount of pressure. The weighted rollers ensure that the sheet will be firmly pressed against the hot plates, and that frictional forces between the corrugator belt and the sheet will be sufficiently large to enable the belt to pull the sheet. As well as this drying function, the belt must pass the corrugated box-board through the cooling section and onto the next stage.
[0016] In view of the description noted above, corrugator belts must possess certain features such as strength, durability, be dimensionally stable, and have a non-marking seam under all the conditions of high temperature steam, plus high tension. Furthermore, the belts should be flexible in the machine direction yet be sufficiently stable in the cross machine direction so as to maintain close to the belt's original dimensions and facilitate the ability to be guided along its passage around the machine under the conditions described. More importantly, the belts should be sufficiently permeable to allow the evaporation of vapor to pass easily through the material so as not to rewet the corrugated box-board.
[0017] However, corrugator belts exhibiting all of the above desirable features have heretofore not been available. Conventional corrugator belts exhibited low permeability and used the principle of adsorption and then evaporation but problems of rewetting the corrugated box-board occurred which means the corrugator machine was restricted to speed because drying was being restricted. Moreover, these types of belts were typically heavy and very low in permeability.
SUMMARY OF THE INVENTION
[0018] The fabric disclosed herein addresses these needs explained above.
[0019] The present invention relates to a fabric including: a monofilament woven base woven in a machine direction and a cross direction substantially transverse to the machine direction, wherein the fabric comprises a non-marking loop seam integrated with machine direction yarns.
[0020] The fabric can further include a needled batt in a density of about 3.3 decitex to about 100 decitex.
[0021] The batt can be constructed of at least one of nylon and PET.
[0022] The monofilaments in the monofilament woven base can have a diameter of about 0.1 mm to about 2.0 mm.
[0023] The monofilaments in the monofilament woven base can have a diameter different in a machine direction than in a cross direction.
[0024] The monofilament woven base can contain 1 to 10 layers of cross machine direction yarns.
[0025] The fabric can have a permeability of about 20 cfm to about 500 cfm.
[0026] The monofilament woven base can be treated on at least one of a machine side or a corrugator side with a resin.
[0027] The monofilament woven base can be constructed of at least one of polyester, nylon, PPS, PET, or PEEK.
[0028] The fabric can be is a corrugator fabric, press felt fabric, or pulp machine fiber cement fabric.
[0029] The present invention relates to a machine including: a fabric including a monofilament woven base woven in a machine direction and a cross direction substantially transverse to the machine direction comprising a non-marking loop seam integrated with machine direction yarns.
[0030] The fabric can further include a needled batt having a density of about 3.3 decitex to about 100 decitex.
[0031] The batt can be constructed of at least one of nylon and PET.
[0032] The monofilaments in the monofilament woven base can have a diameter of about 0.1 mm to about 2.0 mm.
[0033] The monofilaments in the monofilament woven base can have a diameter is different in a machine direction than in a cross direction.
[0034] The monofilament woven base can contain 1 to 10 layers of cross machine direction yarns.
[0035] The fabric can have a permeability of about 20 cfm to about 500 cfm.
[0036] The woven base can be treated on at least one of a machine side or a corrugator side with a resin.
[0037] The machine can be a corrugator machine, press felt machine, or pulp machine.
[0038] The monofilament woven base can be constructed of at least one of polyester, nylon, PPS, PET, or PEEK.
[0039] Other exemplary embodiments and advantages of the present invention may be ascertained by reviewing the present disclosure and the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0040] The present invention is further described in the detailed description which follows, in reference to the noted plurality of drawings by way of non-limiting examples of preferred embodiments of the present invention, in which like numerals represent like elements throughout the several views of the drawings, and wherein:
[0041] FIG. 1 depicts an embodiment of the present invention showing a cross sectional view of the belt taken in the longitudinal or warpwise direction;
[0042] FIG. 2 depicts an embodiment of the present invention showing a cross sectional view of the belt taken in the longitudinal or warpwise direction;
[0043] FIG. 3 depicts an embodiment of the present invention showing a cross sectional view of the belt and pin seam taken in the longitudinal or warpwise direction;
[0044] FIG. 4 is a photograph of an embodiment of the present invention revealing the seam loops with a flap of batt pulled back;
[0045] FIG. 5 is a photograph of an embodiment of the present invention showing the seam with the needled flap depicting the integral nature of the design;
[0046] FIGS. 6-8 are photographs of embodiments of the present invention showing the monofilament base weave, the joined seam loops, and the batt;
[0047] FIG. 9 is a photograph of an embodiment of the present invention showing a double loop seam to give extra strength by the utilization of two base monofilament weaves;
[0048] FIG. 10 is a photograph of an embodiment of the present invention showing the base monofilament weave plus the seam loops before needling the batt onto the belt; and
[0049] FIG. 11 is a photograph of an embodiment of the present invention showing a corrugator machine with the belt of the present invention and stationary metal shoes on the machine side of the corrugator belt.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0050] The particulars shown herein are by way of example and for purposes of illustrative discussion of the embodiments of the present invention only and are presented in the cause of providing what is believed to be the most useful and readily understood description of the principles and conceptual aspects of the present invention. In this regard, no attempt is made to show structural details of the present invention in more detail than is necessary for the fundamental understanding of the present invention, the description taken with the drawings making apparent to those skilled in the art how the several forms of the present invention may be embodied in practice.
[0051] Preliminarily, it is noted that while the discussion of the present invention may refer specifically to corrugator fabrics, the present invention has applicability to other fabrics in the papermaking industry and other industrial applications. For example, the fabrics of the present invention can be used in press felts on a paper machine, or pulp machine fiber cement belts. Additional applications include industrial corrugated fabrics. Fabric constructions include woven, spiral wound, knitted, extruded mesh, spiral-link, spiral coil and other nonwoven fabrics. These fabrics may comprise monofilament, plied monofilament, multifilament or plied multifilament yarns, and may be single-layered, multi-layered or laminated. The yarns are typically extruded from any one of the synthetic polymeric resins, such as polyamide and polyester resins, used for this purpose by those of ordinary skill in the industrial fabric arts.
[0052] Further, when an amount, concentration, or other value or parameter, is given as 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 an upper preferred value and a lower preferred value, regardless whether ranges are separately disclosed.
[0053] FIGS. 1-3 are cross sections of the belt of the present invention where the cross section is taken in the taken in the longitudinal or warpwise direction (machine direction (MD)) of belt, and shows that belt includes a base structure fabric 66 , which includes MD yarns 68 and cross machine-direction (CMD) yarns 70 . As shown in at least FIGS. 1-3 , the base structure fabric 66 may be woven from longitudinal, or machine direction (MD), yarns 68 and transverse, or CMD, yarns 70 . Base structure fabric 66 is depicted as having been woven flat providing at least one running surface 10 , where longitudinal yarns 68 warp and weave over, under and between the stacked pairs of CMD yarns 70 in a duplex weave and joined to form an endless belt. It should be understood, however, that base structure fabric 66 may be woven endless. It should be further understood that base structure fabric 66 may be woven in a single-layer weave, or in any other weave suitable for the purpose.
[0054] By way of non-limiting example, FIG. 1 depicts a fabric having three layers of CMD yarns 70 . However, any number of layers of monofilament are contemplated by the present invention and can be determined, for example, by the desired weight and strength of the fabric, in addition to the desired permeability. Thus, one having ordinary skill in the art would readily modify the number of layers in view of any number of parameters, such as belt length, weight requirements, air flow requirements, and type of board, among other things. By way of non-limiting example, the fabric has from 1 to 10 layers of CMD yarns 70 , preferably from 1 to 4 layers of CMD yarns 70 , and most preferably from 1 to 3 layers of CMD yarns 70 . By way of non-limiting example, FIG. 2 depicts a fabric having two layers of CMD yarns 70 .
[0055] The base structure fabric 66 , which includes MD yarns 68 and CMD yarns 70 , can be a monofilament made of or extruded from a polymeric resin material, or any other material used in the manufacture of paper machine clothing and industrial process fabrics. Thus, by way of non-limiting example, the monofilament base structure fabric 66 may be woven, or otherwise assembled, from warp yarns and weft yarns comprising yarns of any of the varieties used in the manufacture of paper machine clothing and industrial process fabrics. Thus, by way of non-limiting example, base structure fabric 66 may include natural or metal yarns, monofilament, plied monofilament, multifilament, plied multifilament or yarns spun from staple fibers of any of the synthetic polymeric resins used by those skilled in the art in the manufacture of fabrics intended for use in high-temperature environments. For example, the base structure fabric 66 may be manufactured from any combination of yarns of the following materials: nylon; polyaramids, such as Nomex®, and Kevlar®; polyphenylene sulfide (PPS), which is more commonly known as Ryton®; an aromatic polyester, which is commonly known as VECTRAN®; polyetheretherketone (PEEK); polybutylene terephthalate; polyethylene terephthalate (PET); polyester and blends thereof, such as for example, Synstrand's WFP-905 polyester yarn.
[0056] By way of non-limiting example, the base structure fabric 66 may comprise yarns of polyester in the machine direction and Ryton® or polyester monofilament yarns in the cross-machine direction. It is contemplated by the present invention to use differing sizes of CMD and MD yarns, and differing materials for CMD and MD yarns. Therefore, by way of non-limiting example, a fabric can be made of MD yarns having a thickness greater than the CMD yarns, or vice versa.
[0057] The base structure fabric 66 of the present invention can provide any number of the following advantages, for example: increased drying rates when used on a corrugator machine, reduced steam consumption and energy to drive the fabric, improved guiding, quicker belt changes due to the lighter, thinner fabric, increased stability of the fabric, especially when using monofilament yarns.
[0058] In an embodiment of the present invention, the base structure fabric 66 can be composed of monofilament yarns, with a diameter of approximately 0.1 mm to approximately 2.00 mm diameter, preferably approximately 0.2 mm to approximately 0.6 mm diameter, and most preferably approximately 0.3 mm to approximately 0.5 mm diameter.
[0059] Another aspect of the present invention is the incorporation of a non-marking pin seam 85 which includes pin 80 woven into MD yarns, wherein the yarns in the MD form the seam loops, and the seam loops are formed by MD yarns that are completely in-line with the base weave. By way of non-limiting example, FIG. 3 depicts a pin seam 85 which includes pin 80 integrated with the MD yarns 68 . The pin 80 of the present invention can be made of any material with sufficient strength to hold together the belt of the present invention. By way of non-limiting example, the pin 80 can be formed of polyester, and further by way of non-limiting example, the pin seam has a diameter smaller than the overall thickness of the base structure fabric 66 . By way of a non-limiting example, the pin 80 can include a plurality of pins
[0060] Advantages of having pin seam 85 including pin 80 integrated with the MD yarns include: having a tension line completely in the central zone thereby substantially elimination the chance of marking from uneven pressure. In addition, the permeability in the seam area is preferably not lower than the body of the fabric, i.e., the seam loops and base material of the fabric are substantially the same diameter, plus the batt in the vicinity of the pin seam is substantially the same as the needled cover on the base material.
[0061] By way of non-limiting example, the seam loops are formed at the sides of the fabric by the weft on the loom. The weft on the loom becomes the machine direction (MD) on the corrugator or paper machine and the warp on the loom becomes the cross machine direction (CMD), i.e., the fabric is woven with the length of the fabric determined by the width in the loom.
[0062] In addition, when a batt 60 is provided on the base fabric of the present invention, the batt 60 creates the necessary softness and friction desired for all kinds of boxboard production. It should be noted that the fabric of the present invention is unlike any traditional needled fabrics which have a non monofilament base structure (skeleton). Traditional fabrics have a very low permeability (e.g., less than 50 cfm). However, because fabric of the of the present invention can be constructed of a very strong monofilament base, there is no need to needle as much batt onto the base structure to obtain the necessary stability for boxboard production. Therefore, the permeability of the monofilament base corrugator fabric of the present invention can be as much as 4 to 10 times higher in permeability than conventional corrugator fabrics.
[0063] By way of non-limiting example, the permeability of the fabric of the present invention (including batt 60 ) is in the range of approximately 20 to approximately 500 cfm, and preferably approximately 40 cfm to approximately 200 cfm, and most preferably approximately 50 cfm to approximately 100 cfm.
[0064] The base structure fabric 66 can optionally be treated with a resin (e.g., EWR resin by Voith Paper) such that when the base structure fabric 66 is mounted on a machine, either the board side of the belt, machine side of the belt, or both sides of the belt, contain a protective resin coating.
[0065] One or both sides of the base structure fabric 66 may be needled with a web of staple fiber material such as batt 60 in such a manner that the fibers are driven into the structure of the base structure fabric 66 . One or more layers of batt 60 , may be needled into one or both sides of the base structure fabric 66 , and the web of the batt may extend partially or completely through the base structure fabric 66 . The batt used for this purpose may be of nylon, PET, polyester, polypropylene, polyamide, acrylic fibers.
[0066] By way of non-limiting example, the batt 60 is provided on the base structure fabric 66 in a range of approximately 3.3 to approximately 100 decitex, and preferably approximately 14 to approximately 44 decitex. The batt 60 can be applied to the base structure, such that when the base structure fabric 66 is mounted on a machine, either the board side of the belt, machine side of the belt, or both sides of the belt, contain batt, as shown by way of non-limiting example in FIGS. 1-2 and 5 - 9 . It should be noted that batt 60 is not shown in FIG. 3 for the sake of clarity, but the present invention contemplates using batt 60 in the vicinity of pin seam 85 .
[0067] By way of non-limiting example, FIG. 4 represents a photograph of an embodiment of the present invention revealing the seam loops with a flap of batt pulled back.
[0068] By way of non-limiting example, FIG. 5 represents a photograph of an embodiment of the present invention showing the seam with the needled flap depicting the integral nature of the design.
[0069] By way of non-limiting example, FIGS. 6-8 represents photographs of embodiments of the present invention showing the monofilament base weave, the joined seam loops, and the batt.
[0070] By way of non-limiting example, FIG. 9 represents a photograph of an embodiment of the present invention showing a double loop seam to give extra strength by the utilization of two base monofilament weaves.
[0071] By way of non-limiting example, FIG. 10 represents a photograph of an embodiment of the present invention showing the base monofilament weave plus the seam loops before needling the batt onto the belt.
[0072] By way of non-limiting example, FIG. 11 represents a photograph of an embodiment of the present invention showing a corrugator machine with the belt of the present invention and stationary metal shoes on the machine side of the corrugator belt. It is noted that the belt of the present invention can be used on any corrugator machine, and is also not limited thereto. By way of non-limiting example, the belt can also be used on paper machines used to press felts, and on pulp machines.
EXAMPLE 1
[0073] A fabric for a corrugator machine was constructed using a pin seam which was inserted into a monofilament base using Synstrand WFP-905 polyester MD yarn with a diameter of 0.40 mm. After weaving the monofilament base, a nylon batt was needle punched into the monofilament woven base resulting in a 1900 gsm fabric weight, 0.205″ caliper, and 50-100 cfm. The resulting fabric was then treated with a resin (EWR resin, a product of Voith Paper) on the inside (i.e., machine side, for resistance to the stationary metal shoes). The outside (i.e., box-board side) was also lightly resin treated (EWR resin, a product of Voith Paper) to give extra durability to the surface of the corrugator fabric without sacrificing softness to the board.
[0074] It is noted that the foregoing examples have been provided merely for the purpose of explanation and are in no way to be construed as limiting of the present invention. While the present invention has been described with reference to exemplary embodiments, it is understood that the words which have been used herein are words of description and illustration, rather than words of limitation. Changes may be made, within the purview of the appended claims, as presently stated and as amended, without departing from the scope and spirit of the present invention in its aspects. Although the present invention has been described herein with reference to particular means, materials and embodiments, the present invention is not intended to be limited to the particulars disclosed herein; rather, the present invention extends to all functionally equivalent structures, methods and uses, such as are within the scope of the appended claims. | The present invention relates generally to papermaking, and relates more specifically to fabrics employed in making press felts on a paper machine, pulp machine fiber cement belts, and corrugated paper board, or box-board. The invention also relates to the monofilament base of fabric optionally with a needled batt which can provide one or more of the following advantages: hydrolysis resistant materials, providing light weight high strength fabrics, having a high permeability, and soft surface with a high coefficient of friction. The present invention also relates to an integrated loop seam integrated with machine direction yarns of the monofilament base which can provide one or more of the following advantages: extremely stable and flexible corrugator fabric, and the ability to provide a non-marking loop seam. | 3 |
CROSS REFERENCE TO RELATED APPLICATIONS
This application is a Divisional Application of U.S. patent application Ser. No. 11/206,484, filed Aug. 17, 2005 now U.S. Pat. No. 7,894,911, which is a Divisional Application of U.S. patent application Ser. No. 09/515,373, filed Feb. 29, 2000 now abandoned, which claims the benefit of U.S. Provisional Application No. 60/125,873, filed Mar. 24, 1999.
TECHNICAL FIELD OF INVENTION
The present invention relates to electrical stimulation of the retina to produce artificial images for the brain. It relates to electronic image stabilization techniques based on tracking the movements of the eye. It relates to telemetry in and out of the eye for uses such as remote diagnostics and recording from the retinal surface.
The present invention also relates to electrical stimulation of the retina to produce phosphenes and to produce induced color vision. The present invention relates to hermetically sealed electronic and electrode units which are safe to implant in the eye.
BACKGROUND
Color perception is part of the fabric of human experience. Homer (c. 1100 b.c.) writes of “the rosy-fingered dawn”. Lady Murasaki no Shikibu (c. 1000 a.d.) uses word colors (“purple, yellow shimmer of dresses, blue paper”) in the world's first novel. In the early nineteenth century Thomas Young, an English physician, proposed a trichromatic theory of color vision, based on the action of three different retinal receptors. Fifty years later James Clerk Maxwell, the British physicist and Hermann von Helmholtz, the German physiologist, independently showed that all of the colors we see can be made up from three suitable spectral color lights. In 1964 Edward MacNichol and colleagues at Johns Hopkins and George Wald at Harvard measured the absorption by the visual pigments in cones, which are the color receptor cells. Rods are another type of photoreceptor cell in the primate retina. These cells are more sensitive to dimmer light but are not directly involved in color perception. The individual cones have one of three types of visual pigment. The first is most sensitive to short waves, like blue. The second pigment is most sensitive to middle wavelengths, like green. The third pigment is most sensitive to longer wavelengths, like red.
The retina can be thought of a big flower on a stalk where the top of that stalk is bent over so that the back of the flower faces the sun. In place of the sun, think of the external light focused by the lens of the eye onto the back of the flower. The cones and rods cells are on the front of the flower; they get the light which has passed through from the back of the somewhat transparent flower. The photoreceptor nerve cells are connected by synapses to bipolar nerve cells, which are then connected to the ganglion nerve cells. The ganglion nerve cells connect to the optic nerve fibers, which is the “stalk” that carries the information generated in the retina to the brain. Another type of retinal nerve cell, the horizontal cell, facilitates the transfer of information horizontally across bipolar cells. Similarly, another type of cell, the amacrine facilitates the horizontal transfer of information across the ganglion cells. The interactions among the retinal cells can be quite complex. On-center and off-center bipolar cells can be stimulated at the same time by the same cone transmitter release to depolarize and hyperpolarize, respectively. A particular cell's receptive field is that part of the retina, which when stimulated, will result in that cell's stimulation. Thus, most ganglion cells would have a larger receptive field than most bipolar cells. Where the response to the direct light on the center of a ganglion cells receptive field is antagonized by direct light on the surround of its receptive field, the effect is called center-surround antagonism. This phenomenon is important for detecting borders independent of the level of illumination. The existence of this mechanism for sharpening contrast was first suggested by the physicist Ernst Mach in the late 1800's. More detailed theories of color vision incorporate color opponent cells. On the cone level, trichromatic activity of the cone cells occurs. At the bipolar cell level, green-red opponent and blue-yellow opponent processing systems of the center-surround type, occur. For example, a cell with a green responding center would have a annular surround area, which responded in an inhibiting way to red. Similarly there can be red-center responding, green-surround inhibiting response. The other combinations involve blue and yellow in an analogous manner.
It is widely known that Galvani, around 1780, stimulated nerve and muscle response electrically by applying a voltage on a dead frog's nerve. Less well known is that in 1755 LeRoy discharged a Leyden jar, i.e., a capacitor, through the eye of a man who had been blinded by the growth of a cataract. The patient saw “flames passing rapidly downward.”
In 1958, Tassicker was issued a patent for a retinal prosthetic utilizing photosensitive material to be implanted subretinally. In the case of damage to retinal photoreceptor cells that affected vision, the idea was to electrically stimulate undamaged retinal cells. The photosensitive material would convert the incoming light into an electrical current, which would stimulate nearby undamaged cells. This would result in some kind of replacement of the vision lost. Tassicker reports an actual trial of his device in a human eye. (U.S. Pat. No. 2,760,483).
Subsequently, Michelson (U.S. Pat. No. 4,628,933), Chow (U.S. Pat. Nos. 5,016,633; 5,397,350; 5,556,423), and De Juan (U.S. Pat. No. 5,109,844) all were issued patents relating to a device for stimulating undamaged retinal cells. Chow and Michelson made use of photodiodes and electrodes. The photodiode was excited by incoming photons and produced a current at the electrode.
Normann et al. (U.S. Pat. No. 5,215,088) discloses long electrodes 1000 to 1500 microns long designed to be implanted into the brain cortex. These spire-shaped electrodes were formed of a semiconductor material.
Najafi, et al., (U.S. Pat. No. 5,314,458), disclosed an implantable silicon-substrate based microstimulator with an external device which could send power and signal to the implanted unit by RF means. The incoming RF signal could be decoded and the incoming RF power could be rectified and used to run the electronics.
Difficulties can arise if the photoreceptors, the electronics, and the electrodes all tend to be mounted at one place. One issue is the availability of sufficient area to accommodate all of the devices, and another issue is the amount of power dissipation near the sensitive retinal cells. Since these devices are designed to be implanted into the eye, this potential overheating effect is a serious consideration.
Since these devices are implants in the eye, a serious problem is how to hermetically seal these implanted units. Of further concern is the optimal shape for the electrodes and for the insulators, which surround them. In one embodiment there is a definite need that the retinal device and its electrodes conform to the shape of the retinal curvature and at the same time do not damage the retinal cells or membranes.
The length and structure of electrodes must be suitable for application to the retina, which averages about 200 microns in thickness. Based on this average retinal thickness of 200 microns, elongated electrodes in the range of 100 to 500 microns appear to be suitable. These elongated electrodes reach toward the cells to be activated. Being closer to the targeted cell, they require less current to activate it.
In order not to damage the eye tissue there is a need to maintain an average charge neutrality and to avoid introducing toxic or damaging effects from the prosthesis.
A desirable property of a retinal prosthetic system is making it possible for a physician to make adjustments on an on-going basis from outside the eye. One way of doing this would have a physician's control unit, which would enable the physician to make adjustments and monitor the eye condition. An additional advantageous feature would enable the physician to perform these functions at a remote location, e.g., from his office. This would allow one physician to remotely monitor a number of patients remotely without the necessity of the patient coming to the office. A patient could be traveling distantly and obtain physician monitoring and control of the retinal color prosthetic parameters.
Another version of the physician's control unit is a hand-held, palm-size unit. This unit will have some, but not all of the functionality of the physician's control unit. It is for the physician to carry on his rounds at the hospital, for example, to check on post-operative retinal-prosthesis implant patients. Its extreme portability makes other situational uses possible, too, as a practical matter.
The patient will want to control certain aspects of the visual image from the retinal prosthesis system, in particular, image brightness. Consequently, a patient controller, performing fewer functions than the physician's controller is included as part of the retinal prosthetic system. It will control, at a minimum, bright image, and it will control this image brightness in a continuous fashion. The image brightness may be increased or decreased by the patient at any time, under normal circumstances.
A system of these components would itself constitute part of a visual prosthetic to form images in real time within the eye of a person with a damaged retina. In the process of giving back sight to those who are unable to see, it would be advantageous to supply artificial colors in this process of reconstructing sight so that the patient would be able to enjoy a much fuller version of the visual world.
In dealing with externally mounted or externally placed means for capturing image and transmitting it by electronic means or other into the eye, one must deal with the problem of stabilization of the image. For example, a head-mounted camera would not follow the eye movement. It is desirable to track the eye movements relative to the head and use this as a method or approach to solving the image stabilization problem.
By having a method and apparatus for the physician and the technician to initially set up and measure the internal activities and adjust these, the patient's needs can be better accommodated. The opportunity exists to measure internal activity and to allow the physician, using his judgment, to adjust settings and controls on the electrodes. Even the individual electrodes would be adjusted by way of the electronics controlling them. By having this done remotely, by remote means either by telephone or by the Internet or other such, it is clear that a physician would have the capability to intervene and make adjustment as necessary in a convenient and inexpensive fashion, to serve many patients.
SUMMARY OF INVENTION
The objective of the current invention is to restore color vision, in whole or in part, by electrically stimulating undamaged retinal cells, which remain in patients with lost or degraded visual function arising, for example, from Retinitis Pigmentosa or Age-Related Macular Degeneration. This invention is directed toward patients who have been blinded by degeneration of photoreceptors; but who have sufficient bipolar cells, or other cells acting similarly, to permit electrical stimulation.
There are three main functional parts to this invention. One is external to the eye. The second part is internal to the eye. The third part is the communication circuitry for communicating between those two parts. Structurally there are two parts. One part is external to the eye and the other part in implanted within the eye. Each of these structural parts contains two way communication circuitry for communication between the internal and external parts.
The structural external part is composed of a number of subsystems. These subsystems include an external imager, an eye-motion compensation system, a head motion compensation system, a video data processing unit, a patient's controller, a physician's local controller, a physician's remote controller, and a telemetry unit. The imager is a video camera such as a CCD or CMOS video camera. It gathers an image approximating what the eyes would be seeing if they were functional.
The imager sends an image in the form of electrical signals to the video data processing unit. In one aspect, this unit formats a grid-like or pixel-like pattern that is then ultimately sent to electronic circuitry (part of the internal part) within the eye, which drives the electrodes. These electrodes are inside the eye. They replicate the incoming pattern in a useable form for stimulation of the retina so as to reproduce a facsimile of the external scene. In an other aspect of this invention other formats other than a grid-like or pixel like pattern are used, for example a line by line scan in some order, or a random but known order, point-by-point scan. Almost any one-to-one mapping between the acquired image and the electrode array is suitable, as long as the brain interprets the image correctly.
The imager acquires color information. The color data is processed in the video data processing unit. The video data processing unit consists of microprocessor CPU's and associated processing chips including high-speed data signal processing (DSP) chips.
In one aspect, the color information is encoded by time sequences of pulses separated by varying amounts of time; and, the pulse duration may be different for various pulses. The basis for the color encoding is the individual color code reference ( FIG. 2 a ). The electrodes stimulate the target cells so as to create a color image for the patient, corresponding to the original image as seen by the video camera, or other imaging means.
Color information, in an alternative aspect, is sent from the video data processing unit to the electrode array, where each electrode has been determined to stimulate preferentially one of the bipolar cell types, namely, red-center green-surround, green-center-red-surround, blue-center-yellow-surround, or yellow-center-blue-surround.
An eye-motion compensation system is an aspect of this invention. The eye tracker is based on detection of eye motion from the corneal reflex or from implanted coils of wire, or, more generally, insulated conductive coils, on the eye or from the measurement of electrical activity of extra-ocular muscles. Communication is provided between the eye tracker and the video data processing unit by electromagnetic or acoustical telemetry. In one embodiment of the invention, electromagnetic-based telemetry may be used. The results of detecting the eye movement are transmitted to a video data processing unit, together with the information from the camera means. Another aspect of the invention utilizes a head motion sensor and head motion compensation system. The video data processing unit can incorporate the data of the motion of the eye as well as that of the head to further adjust the image electronically so as to account for eye motion and head motion.
The internal structural part which is implanted internally within the eye, is also composed of a number of subsystems. These can be categorized as electronic circuits and electrode arrays, and communication subsystems, which may include electronic circuits. The circuits, the communication subsystems, and the arrays can be hermetically sealed and they can be attached one to the other by insulated wires. The electrode arrays and the electronic circuits can be on one substrate, or they may be on separate substrates joined by an insulated wire or by a plurality of insulated wires. This is similarly the case for a communication subsystem.
A plurality of predominately electronic substrate units and a plurality of predominately electrode units may be implanted or located within the eye as desired or as necessary. The electrodes are designed so that they and the electrode insulation conform to the retinal curvature. The variety of electrode arrays include recessed electrodes so that the electrode array surface coming in contact with the retinal membrane or with the retinal cells is the non-metallic, more inert insulator.
Another aspect of the invention is the elongated electrode, which is designed to stimulate deeper retinal cells by penetrating into the retina by virtue of the length of its electrodes. A plurality of electrodes is used. The elongated electrodes are of lengths from 100 microns to 500 microns. With these lengths, the electrode tips can reach through those retinal cells not of interest but closer to the target stimulation cells, the bipolar cells. The number of electrodes may range from 100 on up to 10,000 or more. With the development of electrode fabrication technology, the number of electrodes might rage up to one million or more.
Another aspect of the invention uses a plurality of capacitive electrodes to stimulate the retina, in place of non-capacitive electrodes. Another aspect of the invention is the use of a neurotrophic factor, for example, Nerve Growth Factor, applied to the electrodes, or to the vicinity of the electrodes, to aid in attracting target nerves and other nerves to grow toward the electrodes.
Hermetic sealing is accomplished by coating the object to be sealed with a substance selected from the group consisting of silicon carbide, diamond-like coating, silicon nitride and silicon oxide in combination, titanium oxide, tantalum oxide, aluminum nitride, aluminum oxide, zirconium oxide. This hermetic sealing aspect of the invention provides an advantageous alternative to glass coverings for hermetic seals, being less likely to become damaged.
Another feature of one aspect of the structural internal-to-the-eye subsystems is that the electronics receive and transmit information in coded or pulse form via electromagnetic waves. In the case where electromagnetic waves are used, the internal-to-the-eye implanted electronics can rectify the RF, or electromagnetic wave, current and decode it. The power being sent in through the receiving coil is extracted and used to drive the electronics. In some instances, the implanted electronics acquire data from the electrode units to transmit out to the video data processing unit.
In another aspect the information coding is done with ultrasonic sound. An ultrasonic transducer replaces the electromagnetic wave receiving coil inside the eye. An ultrasonic transducer replaces the coil outside the eye for the ultrasonic case. By piezoelectric effects, the sound vibration is turned into electrical current, and energy extracted therefrom.
In another aspect of the invention, information is encoded by modulating light. For the light modulation case, a light emitting diode (LED) or laser diode or other light generator, capable of being modulated, acts as the information transmitter. Information is transferred serially by modulating the light beam, and energy is extracted from the light signal after it is converted to electricity. A photo-detector, such as a photodiode, which turns the modulated light signal into a modulated electrical signal, is used as a receiver.
Another aspect of the structural internal-to-the-eye subsystems of this invention is that the predominately electrode array substrate unit and the predominately electronic substrate unit, which are joined by insulated wires, can be placed near each other or in different positions. For example, the electrode array substrate unit can be placed subretinally and the electronic substrate unit placed epiretinally. On a further aspect of this invention, the electronic substrate unit can be placed distant from the retina so as to avoid generating additional heat or decreasing the amount of heat generated near the retinal nerve system. For example, the receiving and processing circuitry could be placed in the vicinity of the pars plana. In the case where the electronics and the electrodes are on the same substrate chip, two of these chips can be placed with the retina between them, one chip subretinal and the other chip epiretinal, such that the electrodes on each may be aligned. Two or more guide pins with corresponding guide hole or holes on the mating chip accomplish the alignment. Alternatively, two or more tiny magnets on each chip, each magnet of the correct corresponding polarity, may similarly align the sub- and epiretinal electrode bearing chips. Alternatively, corresponding parts which mate together on the two different chips and which in a fully mated position hold each other in a locked or “snap-together” relative position.
Now as an element of the external-to-the-eye structural part of the invention, there is a provision for a physician's hand-held test unit and a physician's local or remote office unit or both for control of parameters such as amplitudes, pulse widths, frequencies, and patterns of electrical stimulation.
The physician's hand-held test unit can be used to set up or evaluate and test the implant during or soon after implantation at the patient's bedside. It has, essentially, the capability of receiving what signals come out of the eye and having the ability to send information in to the retinal implant electronic chip. For example, it can adjust the amplitudes on each electrode, one at a time, or in groups. The hand-held unit is primarily used to initially set up and make a determination of the success of the retinal prosthesis.
The physician's local office unit, which may act as a set-up unit as well as a test unit, acts directly through the video data processing unit. The remote physician's office unit would act over the telephone lines directly or through the Internet or a local or wide area network. The office units, local and remote, are essentially the same, with the exception that the physician's remote office unit has the additional communications capability to operate from a location remote from the patient. It may evaluate data being sent out by the internal unit of the eye, and it may send in information. Adjustments to the retinal color prosthesis may be done remotely so that a physician could handle a multiple number of units without leaving his office. Consequently this approach minimizes the costs of initial and subsequent adjustments.
BRIEF DESCRIPTION OF THE DRAWINGS
The above and other features and advantages of the invention will be more apparent from the following detailed description wherein:
FIG. 1 a shows the general structural aspects of the retina color prosthesis system;
FIG. 1 b shows the retina color prosthesis system with a structural part internal (to the eye), with an external part with subsystems for eye-motion feedback to enable maintaining a stable image presentation, and with a subsystems for communicating between the internal and external parts, and other structural subsystems;
FIG. 1 c shows an embodiment of the retina color prosthesis system which is, in part, worn in eyeglass fashion;
FIG. 1 d shows the system in FIG. 1 c in side view;
FIG. 2 a shows an embodiment of the color I coding schemata for the stimulation of the sensation of color;
FIG. 2 b represents an embodiment of the color I conveying method where a “large” electrode stimulates many bipolar cells with the color coding schemata of FIG. 2 a;
FIG. 2 c represents an embodiment of the color II conveying method where an individual electrode stimulates a single type of bipolar cell;
FIG. 3 a represents an embodiment of the telemetry unit including an external coil, an internal (to the eye) coil, and an internal electronic chip;
FIG. 3 b represents an embodiment of the telemetry unit including an external coil, an internal (to the eye) coil, an external electronic chip, a dual coil transfer unit, and an internal electrode array;
FIG. 3 c shows and acoustic energy and information transfer system;
FIG. 3 d shows a light energy and information transfer system;
FIG. 4 represents an embodiment of the external telemetry unit;
FIG. 5 shows an embodiment of an internal telemetry circuit and electrode array switcher;
FIG. 6 a shows a monopolar electrode arrangement and illustrates a set of round electrodes on a substrate material;
FIG. 6 b shows a bipolar electrode arrangement;
FIG. 6 c shows a multipolar electrode arrangement;
FIG. 7 shows the corresponding indifferent electrode for monopolar electrodes;
FIG. 8 a depicts the location of an epiretinal electrode array located inside the eye in the vitreous humor located above the retina, toward the lens capsule and the aqueous humor;
FIG. 8 b shows recessed epiretinal electrodes where the electrically conducting electrodes are contained within the electrical insulation material; a silicon chip acts as a substrate; and the electrode insulator device is shaped so as to contact the retina in a conformal manner;
FIG. 8 c is a rendering of an elongated epiretinal electrode array with the electrodes shown as pointed electrical conductors, embedded in an electrical insulator, where an pointed electrodes contact the retina in a conformal manner, however, elongated into the retina;
FIG. 9 a shows the location of a subretinal electrode array below the retina, away from the lens capsule and the aqueous humor. The retina separates the subretinal electrode array from the vitreous humor;
FIG. 9 b illustrates the subretinal electrode array with pointed elongated electrode, the insulator, and the silicon chip substrate where the subretinal electrode array is in conformal contact with the retina with the electrodes elongated to some depth;
FIG. 10 a shows a iridium electrode that comprises a iridium slug, an insulator, and a device substrate where this embodiment shows the iridium slug electrode flush with the extent of the insulator;
FIG. 10 b indicates an embodiment similar to that shown in FIG. 10 / 12 a , however, the iridium slug is recessed from the insulator along its sides, but with its top flush with the insulator;
FIG. 10 c shows an embodiment with the iridium slug as in FIG. 10 / 12 b ; however, the top of the iridium slug is recessed below the level of the insulator;
FIG. 10 d indicates an embodiment with the iridium slug coming to a point and insulation along its sides, as well as a being within the overall insulation structure;
FIG. 10 e indicates an embodiment of a method for fabricating and the fabricated iridium electrode where on a substrate of silicon an aluminum pad is deposited; on the pad the conductive adhesive is laid and platinum or iridium foil is attached thereby; a titanium ring is placed, sputtered, plated, ion implanted, ion beam assisted deposited (IBAD) or otherwise attached to the platinum or iridium foil; silicon carbide, diamond-like coating, silicon nitride and silicon oxide in combination, titanium oxide, tantalum oxide, aluminum nitride, aluminum oxide or zirconium oxide or other insulator will adhere better to the titanium while it would not adhere as well to the platinum or iridium foil;
FIG. 11 a depicts a preferred electrode where it is formed on a silicon substrate and makes use of an aluminum pad, a metal foil such as platinum or iridium, conductive adhesive, a titanium ring, aluminum or zirconium oxide, an aluminum layer, and a mask;
FIG. 11 b shows an elongated electrode formed on the structure of FIG. 11 a with platinum electroplated onto the metal foil, the mask removed and insulation applied over the platinum electrode;
FIG. 11 c shows a variation of a form of the elongated electrode wherein the electrode is thinner and more recessed from the well sides;
FIG. 11 d shows a variation of a form of the elongated electrode wherein the electrode is squatter but recessed from the well sides;
FIG. 11 e shows a variation of a form of the elongated electrode wherein the electrode is a mushroom shape with the sides of its tower recessed from the well sides and its mushroom top above the oxide insulating material;
FIG. 12 a shows the coil attachment to two different conducting pads at an electrode node;
FIG. 12 b shows the coil attachment to two different conducting pads at an electrode node, together with two separate insulated conducting electrical pathways such as wires, each attached at two different electrode node sites on two different substrates;
FIG. 12 c shows an arrangement similar to that seen in FIG. 12 / 16 d , with the difference that the different substrates are very close with a non-conducting adhesive between them and an insulator such as aluminum or zirconium oxide forms a connection coating over the two substrates, in part;
FIG. 12 d depicts an arrangement similar to that seen in FIG. 12 / 16 c ; however, the connecting wires are replaced by an externally placed aluminum conductive trace;
FIG. 13 shows a hermetically sealed flip-chip in a ceramic or glass case with solder ball connections to hermetically sealed glass frit and metal leads;
FIG. 14 shows a hermetically sealed electronic chip as in FIG. 18 with the addition of biocompatible leads to pads on a remotely located electrode substrate;
FIG. 15 shows discrete capacitors on the electrode-opposite side of an electrode substrate;
FIG. 16 a shows an electrode-electronics retinal implant placed with the electrode half implanted beneath the retina, subretinally, while the electronics half projects above the retina, epiretinally;
FIG. 16 b shows another form of sub- and epi-retinal implantation wherein half of the electrode implant is epiretinal and half is subretinal;
FIG. 16 c shows the electrode parts are lined up by alignment pins or by very small magnets;
FIG. 16 d shows the electrode part lined up by template shapes which may snap together to hold the parts in a fixed relationship to each other;
FIG. 17 a shows the main screen of the physician's (local) controller (and programmer);
FIG. 17 b illustrates the pixel selection of the processing algorithm with the averaging of eight surrounding pixels chosen as one element of the processing;
FIG. 17 c represents an electrode scanning sequence, in this case the predefined sequence, A;
FIG. 17 d shows electrode parameters, here for electrode B, including current amplitudes and waveform timelines;
FIG. 17 e illustrates the screen for choosing the global electrode configuration, monopolar, bipolar, or multipolar;
FIG. 17 f renders a screen showing the definition of bipolar pairs (of electrodes);
FIG. 17 g shows the definition of the multipole arrangements;
FIG. 18 a illustrates the main menu screen for the palm-sized test unit;
FIG. 18 b shows a result of pressing on the stimulate bar of the main menu screen, where upon pressing the start button the amplitudes A 1 and A 2 are stimulated for times t 1 , t 2 , t 3 , and t 4 , until the stop button is pressed;
FIG. 18 c exhibits a recording screen that shows the retinal recording of the post-stimulus and the electrode impedance;
FIG. 19 a - c show the physician's remote controller that has the same functionality inside as the physician's controller but with the addition of communication means such as telemetry or telephone modem; and
FIG. 20 shows the patient's controller unit.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The following description is of the best mode presently contemplated for carrying out the invention. This description is not to be taken in a limiting sense, but is merely made for the purpose of describing the general principles of the invention. The scope of the invention should be determined with reference to the claims.
Objective
The objective of the embodiments of the current invention is a retinal color prosthesis to restore color vision, in whole or in part, by electrically stimulating undamaged retinal cells, which remain in patients with, lost or degraded visual function. Embodiments of this retinal color prosthesis invention are directed toward helping patients who have been blinded by degeneration of photoreceptors and other cells; but who have sufficient bipolar cells and the like to permit the perception of color vision by electric stimulation. By color vision, it is meant to include black, gray, and white among the term color.
General Description
Functionally, there are three main parts to an embodiment of this retinal color prosthesis invention. See FIG. 1 a . FIG. 1 a is oriented toward showing the main structural parts and subsystems, with a dotted enclosure to indicate a functional intercommunications aspect. The first part of the embodiment is external ( 1 ) to the eye. The second part is implanted internal ( 2 ) to the eye. The third part is means for communication between those two parts ( 3 ). Structurally there are two parts. One part is external ( 1 ) to the eye and the other part ( 2 ) is implanted within the eye. Each of these structural parts contains two way communication circuitry for communication ( 3 ) between the internal ( 2 ) and external ( 1 ) parts.
The external part of the retinal color prosthesis is carried by the patient. Typically, the external part including imager, video data processing unit, eye-tracker, and transmitter/receiver are worn as an eyeglass-like unit. Typical of this embodiment, a front view of one aspect of the structural external part ( 1 ) of the color retinal prosthesis is shown in FIG. 1 c and a side view is shown in FIG. 1 d , ( 1 ). In addition, there are two other units which may be plugged into the external unit; when this is done they act as part of the external unit. The physician's control unit is not normally plugged into the external part worn by the patient, except when the physician is conducting an examination and adjustment of the retinal color prosthetic. The patient's controller may or may not be normally plugged in. When the patient's controller is plugged in, it can also receive signals from a remote physician's controller which then acts in the same way as the plug-in physician's controller.
Examining further the embodiment of the subsystems of the external part, see FIG. 1 b . These include an external color imager ( 111 ), an eye-motion compensation system ( 112 ), a head-motion compensation system ( 131 ), a processing unit ( 113 ), a patient's controller ( 114 ), a physician's local controller ( 115 ), a physicians hand-held palm-size pocket-size unit ( 130 ), a physician's remote controller ( 117 ), and a telemetry means ( 118 ). The color imager is a color video camera such as a CCD or CMOS video camera. It gathers an image approximating what the eyes would be seeing if they were functional.
An external imager ( 111 ) sends an image in the form of electrical signals to the video data processing unit ( 113 ). The video data processing unit consists of microprocessor CPU's and associated processing chips including high-speed data signal processing (DSP) chips. This unit can format a grid-like or pixel-like pattern that is sent to the electrodes by way of the telemetry communication subsystems ( 118 , 121 ). See FIG. 1 b . In this embodiment of the retinal color prosthesis ( FIG. 1 b , ( 121 )), these electrodes are incorporated in the internal-to-the eye implanted part.
These electrodes, which are part of the internal implant ( 121 ), together with the telemetry circuitry ( 121 ) are inside the eye. With other internally implanted electronic circuitry ( 121 ), they cooperate with the electrodes so as to replicate the incoming pattern, in a useable form, for stimulation of the retina so as to reproduce a facsimile perception of the external scene. The eye-motion ( 112 ) and head-motion ( 131 ) detectors supply information to the video data processing unit ( 113 ) to shift the image presented to the retina ( 120 ).
There are three preferred embodiments for stimulating the retina via the electrodes to convey the perception of color. Color information is acquired by the imaging means ( 111 ). The color data is processed in the video data processing unit ( 113 ).
First Preferred Color Mode
Color information (See FIG. 2 a ), in the first preferred embodiment, is encoded by time sequences of pulses ( 201 ) separated by varying amounts of time ( 202 ), and also with the pulse duration being varied in time ( 203 ). The basis for the color encoding is the individual color code reference ( 211 through 217 ). The electrodes stimulate the target cells so as to create a color image for the patient, corresponding to the original image as seen by the video camera, or other imaging means. Using temporal coding of electrical stimuli placed (cf. FIG. 2 b , 220 , FIG. 2 c , 230 ) on or near the retina ( FIG. 2 b and FIG. 2 c , 221 , 222 ) the perception of color can be created in patients blinded by outer retinal degeneration. By sending different temporal coding schemes to different electrodes, an image composed of more than one color can be produced. FIG. 2 shows one stimulation protocol. Cathodic stimuli ( 202 ) are below the zero plane ( 220 ) and anodic stimuli ( 203 ) are above. All the stimulus rates are either “fast” ( 203 ) or “slow” ( 202 ) except for green ( 214 ), which includes an intermediate stimulus rate ( 204 ). The temporal codes for the other colors are shown as Red ( 211 ), as Magenta ( 212 ), as Cyan ( 213 ), as Yellow ( 215 ), as Blue ( 216 ), as Neutral ( 217 ). This preferred embodiment is directed toward electrodes which are less densely packed in proximity to the retinal cells.
Second Preferred Color Mode
Color information, in a second preferred embodiment, is sent from the video data processing unit to the electrode array, where each electrode has been determined by test to stimulate one of a bipolar type: red-center green-surround, green-center-red-surround, blue-center-yellow-surround, or yellow-center-blue-surround. In this embodiment, electrodes which are small enough to interact with a single cell, or at most, a few cells are placed in the vicinity of individual bipolar cells, which react to a stimulus with nerve pulse rates and nerve pulse structure (i.e., pulse duration and pulse amplitude). Some of the bipolar cells, when electrically, or otherwise, stimulated, will send red-green signals to the brain. Others will send yellow-blue signals. This refers to the operation of the normal retina. In the normal retina, red or green color photoreceptors (cone cells) send nerve pulses to the red-green bipolar cell which then pass some form of this information up to the ganglion cells and then up to the visual cortex of the brain. With small electrodes individual bipolar cells can be excited in a spatial, or planar, pattern. Small electrodes are those with tip from 0.1 μm to 15 μm, and which individual electrodes are spaced apart from a range 8 μm to 24 μm, so as to approximate a one-to-one correspondence with the bipolar cells. The second preferred embodiment is oriented toward a more densely packed set of electrodes.
Third Preferred Color Mode
A third preferred mode is a combination of the first and of the second preferred modes such that a broader area coverage of the color information encoded by time sequences of pulses, of varying widths and separations and with relatively fewer electrodes is combined with a higher density of electrodes, addressing more the individual bipolar cells.
First Order and Higher Effects
Regardless of a particular theory of color vision, the impinging of colored light on the normal cones, and possibly rods, give rise in some fashion to the perception of color, i.e., multi-spectral vision. In the time-pulse coding color method, above, the absence of all, or sufficient, numbers of working cones (and rods) suggests a generalization of the particular time-pulse color encoding method. The generalization is based on the known, or partly known, neuron conduction pathways in the retina. The cone cells, for example, signal to bipolar cells, which in turn signal the ganglion cells. The original spatial-temporal-color (including black, white) scheme for conveying color information as the cone is struck by particular wavelength photons is then transformed to a patterned signal firing of the next cellular level, say the bipolar cells, unless the cones are absent or don't function. Thus, this second level of patterned signal firing is what one wishes to supply to induce the perception of color vision.
The secondary layer of patterned firing may be close to the necessary primary pattern, in which case the secondary pattern (S) may be represented as P*(1+ε). The * indicates matrix multiplication. P is the primary pattern, represented as a matrix P=
┌p 11 p 1j ┐
└p k1 p kj ┘
where P represents the light signals of a particular spatial-temporal pattern, e.g., flicker signals for green. The output from the first cell layer, say the cones, is then S, the secondary pattern. This represents the output from the bipolar layer in response to the input from the first (cone) layer. If S=P*(1+ε), where 1 represents a vector and ε represents a small deviation applied to the vector 1, then S is represented by P to the lowest order, and by P*(1+ε) to the next order. Thus, the response may be seen as a zero order effect and a first order linear effect. Additional terms in the functional relationship are included to completely define the functional relationship. If S is some non-linear function of P, finding S by starting with P requires more terms then the linear case to define the bulk of the functional relationship. However, regardless of the details of one color vision theory or another, on physiological grounds S is some function of P. As in the case of fitting individual patients with lenses for their glasses, variations of parameters are expected in fitting each patient to a particular temporal coding of electrical stimuli.
Scaling Data from Photoreceptors to Bipolar Cells
As cited above, Greenberg (1998), indicates that electrical and photic stimulation of the normal retina operate via similar mechanisms. Thus, even though electrical stimulation of a retina damaged by outer retinal degeneration is different from the electrical stimulation of a normal retina, the temporal relationships are expected to be analogous.
To explain this, it is noted that electrical stimulation of the normal retinal is accomplished by stimulating the photoreceptor cells (including the color cells activated differentially according to the color of light impinging on them). For the outer retinal degeneration, it is precisely these photoreceptor cells which are missing. Therefore, the electrical stimulation in this case proceeds by way of the cells next up the ladder toward the optic nerve, namely, the bipolar cells.
The time constant for stimulating photoreceptor is about 20 milliseconds. Thus the electrical pulse duration would need to be at least 20 milliseconds. The time constant for stimulating bipolar cells is around 9 seconds. These time constants are much longer than for the ganglion cells (about 1 millisecond). The ganglion cells are another layer of retinal cells closer to the optic nerve. The actual details of the behavior of the different cell types of the retina are quite complicated including the different relationships for current threshold versus stimulus duration (cf. Greenberg, 1998). One may, however, summarize an apparent resonant response of the cells based on their time constants corresponding to the actual pulse stimulus duration.
In FIG. 2 , which is extrapolated from external-to-the-eye electrical stimulation data of Young (1977) and from light stimulation data of Festinger, Allyn, and White (1971), there is shown data that would be applicable to the photoreceptor cells. One may scale the data down based on the ratio of the photoreceptor time constant (about 20 milliseconds) to that of the bipolar cells (about 9 milliseconds). Consequently, 50 milliseconds on the time scale in FIG. 2 now corresponds to 25 milliseconds. Advantageously, stimulation rates and duration of pulses, as well as pulse widths may be chosen which apply to the electrode stimulation of the bipolar cells of the retina.
Eye Movement/Head Motion Compensation
In a preferred embodiment, an external imager such as a color CCD or color CMOS video camera ( 111 ) and a video data processing unit ( 113 ), with an external telemetry unit ( 118 ) present data to the internal eye-implant part. Another aspect of the preferred embodiment is a method and apparatus for tracking eye movement ( 112 ) and using that information to shift ( 113 ) the image presented to the retina. Another aspect of the preferred embodiment utilizes a head motion sensor ( 131 ) and a head motion compensation system ( 131 , 113 ). The video data processing unit incorporates the data of the motion of the eye as well as that of the head to further adjust the image electronically so as to account for eye motion and head motion. Thus electronic image compensation, stabilization and adjustment are provided by the eye and head movement compensation subsystems of the external part of the retinal color prosthesis.
Logarithmic Encoding of Light
In one aspect of an embodiment ( FIG. 1 b ), light amplitude is recorded by the external imager ( 111 ). The video data processing unit uses a logarithmic encoding scheme ( 113 ) to convert the incoming light amplitudes into the logarithmic electrical signals of these amplitudes ( 113 ). These electrical signals are then passed on by telemetry ( 118 ), ( 121 ), to the internal implant ( 121 ) which results in the retinal cells ( 120 ) being stimulated via the implanted electrodes ( 121 ), in this embodiment as part of the internal implant ( 121 ). Encoding is done outside the eye, but may be done internal to the eye, with a sufficient internal computational capability.
Energy and Signal Transmission
Coils
The retinal prosthesis system contains a color imager ( FIG. 1 b , 111 ) such as a color CCD or CMOS video camera. The imaging output data is typically processed ( 113 ) into a pixel-based format compatible with the resolution of the implanted system. This processed data ( 113 ) is then associated with corresponding electrodes and amplitude and pulse-width and frequency information is sent by telemetry ( 118 ) into the internal unit coils, ( 311 ), ( 313 ), ( 314 ) (see FIG. 3 a ). Electromagnetic energy, is transferred into and out from an electronic component ( 311 ) located internally in the eye ( 312 ), using two insulated coils, both located under the conjunctiva of the eye with one free end of one coil ( 313 ) joined to one free end of the second coil ( 314 ), the second free end of said one coil joined to the second free end of said second coil. The second coil ( 314 ) is located in proximity to a coil ( 311 ) which is a part of said internally located electronic component, or, directly to said internally located electronic component ( 311 ). The larger coil is positioned near the lens of the eye. The larger coil is fastened in place in its position near the lens of the eye, for example, by suturing. FIG. 3 b represents an embodiment of the telemetry unit temporally located near the eye, including an external temporal coil ( 321 ), an internal (to the eye) coil ( 314 ), an external-to-the-eye electronic chip ( 320 ), dual coil transfer units ( 314 , 323 ), ( 321 , 322 ) and an internal-to-the-eye electrode array ( 325 ). The advantage of locating the external electronics in the fatty tissue behind the eye is that there is a reasonable amount of space there for the electronics and in that position it appears not to interfere with the motion of the eye.
Ultrasonic Sound
In another aspect the information coding is done with ultrasonic sound and in a third aspect information is encoded by modulating light. An ( FIG. 3 c ) ultrasonic transducer ( 341 ) replaces the electromagnetic wave receiving coil on the implant ( 121 ) inside the eye. An ultrasonic transducer ( 342 ) replaces the coil outside the eye for the ultrasonic case. A transponder ( 343 ) under the conjunctiva of the eye may be used to amplify the acoustic signal and energy either direction. By piezoelectric effects, the sound vibration is turned into electrical current, and energy extracted therefrom.
Modulated Light Beam
For the light modulation ( FIG. 3 d ) case, a light emitting diode (LED) or laser diode or other light generator ( 361 ), capable of being modulated, acts as the information transmitter. Information is transferred serially by modulating the light beam, and energy is extracted from the light signal after it is converted to electricity. A photo-detector ( 362 ), such as a photodiode, which turns the modulated light signal into a modulated electrical signal, is used as a receiver. A set of a photo-generator and a photo-detector are on the implant ( 121 ) and a set is also external to the eye
Prototype-Like Device
FIG. 4 shows an example of the internal-to-the-eye and the external-to-the eve parts of the retinal color prosthesis, together with a means for communicating between the two. The video camera ( 401 ) connects to an amplifier ( 402 ) and to a microprocessor ( 403 ) with memory ( 404 ). The microprocessor is connected to a modulator ( 405 ). The modulator is connected to a coil drive circuit ( 406 ). The coil drive circuit is connected to an oscillator ( 407 ) and to the coil ( 408 ). The coil ( 408 ) can receive energy inductively, which can be used to recharge a battery ( 410 ), which then supplies power. The battery may also be recharged from a charger ( 409 ) on a power line source ( 411 ).
The internal-to-the eye implanted part shows a coil ( 551 ), which connects to both a rectifier circuit ( 552 ) and to a demodulator circuit ( 553 ). The demodulator connects to a switch control unit ( 554 ). The rectifier ( 552 ) connects to a plurality of diodes ( 555 ) which rectify the current to direct current for the electrodes ( 556 ); the switch control sets the electrodes as on or off as they set the switches ( 557 ). The coils ( 408 ) and ( 551 ) serve to connect inductively the internal-to-the-eye ( 500 ) subsystem and the external-to-the patient ( 400 ) subsystem by electromagnetic waves. Both power and information can be sent into the internal unit. Information can be sent out to the external unit. Power is extracted from the incoming electromagnetic signal and may be accumulated by capacitors connected to each electrode or by capacitive electrodes themselves.
Simple Electrode Implant
FIG. 6 a illustrates a set of round monopolar electrodes ( 602 ) on a substrate material ( 601 ). FIG. 7 shows the corresponding indifferent electrode ( 702 ) for these monopolar electrodes, on a substrate ( 701 ), which may be the back of ( 601 ). FIG. 6 b shows a bipolar arrangement of electrodes, both looking down onto the plane of the electrodes, positive ( 610 ) and negative ( 611 ), and also looking at the electrodes sideways to that view, positive ( 610 ) and negative ( 611 ), sitting on their substrate ( 614 ). Similarly for FIG. 6 c where a multipole triplet is shown, with two positive electrodes ( 621 ) and one negative electrode, looking down on their substrate plane, and looking sideways to that view, also showing the substrate ( 614 ).
Epiretinal Electrode Array
FIG. 8 a depicts the location of an epiretinal electrode array ( 811 ) located inside the eye ( 812 ) in the vitreous humor ( 813 ) located above the retina ( 814 ), toward the lens capsule ( 815 ) and the aqueous humor ( 816 );
One aspect of the present embodiment, shown in FIG. 8 b , is the internal retinal color prosthetic part, which has electrodes ( 817 ) which may be flat conductors that are recessed in an electrical insulator ( 818 ). One flat conductor material is a biocompatible metallic foil ( 817 ). Platinum foil is a particular type of biocompatible metal foil. The electrical insulator ( 818 ) in one aspect of the embodiment is silicone.
The silicone ( 818 ) is shaped to the internal curvature of the retina ( 814 ). The vitreous humor ( 813 ), the conductive solution naturally present in the eye, becomes the effective electrode since the insulator ( 818 ) confines the field lines in a column until the current reaches the retina ( 814 ). A further advantage of this design is that the retinal tissue ( 814 ) is only in contact with the insulator ( 818 ), such as silicone, which may be more inactive, and thus, more biocompatible than the metal in the electrodes. Advantageously, another aspect of an embodiment of this invention is that adverse products produced by the electrodes ( 817 ) are distant from the retinal tissue ( 814 ) when the electrodes are recessed.
FIG. 8 c shows elongated epiretinal electrodes ( 820 ). The electrically conducting electrodes ( 820 ) says are contained within the electrical insulation material ( 818 ); a silicon chip ( 819 ) acts as a substrate. The electrode insulator device ( 818 ) is shaped so as to contact the retina ( 814 ) in a conformal manner.
Subretinal Electrode Array
FIG. 9 a shows the location of a subretinal electrode array ( 811 ) below the retina ( 814 ), away from the lens capsule ( 815 ) and the aqueous humor ( 816 ). The retina ( 814 ) separates the subretinal electrode array from the vitreous humor ( 813 ). FIG. 9 b illustrates the subretinal electrode array ( 811 ) with pointed elongated electrodes ( 817 ), the insulator ( 818 ), and the silicon chip ( 819 ) substrate. The subretinal electrode array ( 811 ) is in conformal contact with the retina ( 814 ) with the electrodes ( 817 ) elongated to some depth.
Electrodes
Iridium Electrodes
Now FIG. 10 will illuminate structure and manufacture of iridium electrodes ( FIGS. 10 a - e ). FIG. 10 a shows an iridium electrode, which comprises an iridium slug ( 1011 ), an insulator ( 1012 ), and a device substrate ( 1013 ). This embodiment shows the iridium slug electrode flush with the extent of the insulator. FIG. 10 b indicates an embodiment similar to that shown in FIG. 10 a , however, the iridium slug ( 1011 ) is recessed from the insulator ( 1012 ) along its sides, but with its top flush with the insulator. When the iridium electrodes ( 1011 ) are recessed in the insulating material ( 1012 ), they may have the sides exposed so as to increase the effective surface area without increasing geometric area of the face of the electrode. If an electrode ( 1011 ) is not recessed it may be coated with an insulator ( 1012 ), on all sides, except the flat surface of the face ( 1011 ) of the electrode. Such an arrangement can be embedded in an insulator that has an overall profile curvature that follows the curvature of the retina. The overall profile curvature may not be continuous, but may contain recesses, which expose the electrodes.
FIG. 10 c shows an embodiment with the iridium slug as in FIG. 10 b , however, the top of the iridium slug ( 1011 ) is recessed below the level of the insulator; FIG. 10 d indicates an embodiment with the iridium slug ( 1011 ) coming to a point and insulation along its sides ( 1021 ), as well as a being within the overall insulation structure ( 1021 ). FIG. 10 e indicates an embodiment of a method for fabricating the iridium electrodes. On a substrate ( 1013 ) of silicon, an aluminum pad ( 1022 ) is deposited. On the pad the conductive adhesive ( 1023 ) is laid and platinum or iridium foil ( 1024 ) is attached thereby. A titanium ring ( 1025 ) is placed, sputtered, plated, ion implanted, ion beam assisted deposited (IBAD) or otherwise attached to the platinum or iridium foil ( 1024 ). Silicon carbide, diamond-like coating, silicon nitride and silicon oxide in combination, titanium oxide, tantalum oxide, aluminum nitride, aluminum oxide or zirconium oxide ( 1012 ) or other insulator can adhere better to the titanium ( 1025 ) while it would not otherwise adhere as well to the platinum or iridium foil ( 1024 ). The depth of the well for the iridium electrodes ranges from 0.1 μm to 1 mm.
Elongated Electrodes
Another aspect of an embodiment of the invention is the elongated electrode, which are designed to stimulate deeper retinal cells, in one embodiment, by penetrating the retina. By getting closer to the target cells for stimulation, the current required for stimulation is lower and the focus of the stimulation is more localized. The lengths chosen are 100 microns through 500 microns, including 300 microns. FIG. 8 c is a rendering of an elongated epiretinal electrode array with the electrodes shown as pointed electrical conductors ( 820 ), embedded in an electrical insulator ( 818 ), where the elongated electrodes ( 817 ) contact the retina in a conformal manner, however, penetrating into the retina ( 814 ).
These elongated electrodes, in an aspect of this of an embodiment of the invention may be of all the same length. In a different aspect of an embodiment, they may be of different lengths. Said electrodes may be of varying lengths ( FIG. 8 , 817 ), such that the overall shape of said electrode group conforms to the curvature of the retina ( 814 ). In either of these cases, each may penetrate the retina from an epiretinal position ( FIG. 8 a , 811 ), or, in a different aspect of an embodiment of this invention, each may penetrate the retina from a subretinal position ( FIG. 9 b , 817 ).
One method of making the elongated electrodes is by electroplating with one of an electrode material, such that the electrode, after being started, continuously grows in analogy to a stalagmite or stalactite. The elongated electrodes are 100 to 500 microns in length, the thickness of the retina averaging 200 microns. The electrode material is a substance selected from the group consisting of pyrolytic carbon, titanium nitride, platinum, iridium oxide, and iridium. The insulating material for the electrodes is a substance selected from the group silicon carbide, diamond-like coating, silicon nitride and silicon oxide in combination, titanium oxide, tantalum oxide, aluminum nitride, aluminum oxide or zirconium oxide.
Platinum Electrodes
FIG. 11 ( a - e ) demonstrates a preferred structure of, and method of, making, spiked and mushroom platinum electrodes. Examining FIG. 11 a one sees that the support for the flat electrode ( 1103 ) and other components such as electronic circuits (not shown) is the silicon substrate ( 1101 ). An aluminum pad ( 1102 ) is placed where an electrode or other component is to be placed. In order to hermetically seal-off the aluminum and silicon from any contact with biological activity, a metal foil ( 1103 ), such as platinum or iridium, is applied to the aluminum pad ( 1102 ) using conductive adhesive ( 1104 ). Electroplating is not used since a layer formed by electroplating, in the range of the required thinness, has small-scale defects or holes which destroy the hermetic character of the layer. A titanium ring ( 1105 ) is next placed on the platinum or iridium foil ( 1103 ). Normally, this placement is by ion implantation, sputtering or ion beam assisted deposition (IBAD) methods. Silicon carbide, diamond-like coating, silicon nitride and silicon oxide in combination, titanium oxide, tantalum oxide, aluminum nitride, aluminum oxide or zirconium oxide ( 1106 ) is placed on the silicon substrate ( 1101 ) and the titanium ring ( 1105 ). In one embodiment, an aluminum layer ( 1107 ) is plated onto exposed parts of the titanium ring ( 1105 ) and onto the silicon carbide, diamond-like coating, silicon nitride and silicon oxide in combination, titanium oxide, tantalum oxide, aluminum nitride, aluminum oxide or zirconium oxide ( 1106 ). In this embodiment the aluminum ( 1107 ) layer acts as an electrical conductor. A mask ( 1108 ) is placed over the aluminum layer ( 1107 ).
In forming an elongated, non-flat, electrode ( FIG. 11 b ), platinum is electroplated onto the platinum or iridium foil ( 1103 ). Subsequently, the mask ( 1108 ) is removed and insulation ( 1110 ) is applied over the platinum electrode ( 1109 ).
In FIG. 11 c , a platinum electrode ( 1109 ) is shown which is more internal to the well formed by the silicon carbide, diamond-like coating, silicon nitride and silicon oxide in combination, titanium oxide, tantalum oxide, aluminum nitride, aluminum oxide or zirconium oxide and its titanium ring. The electrode ( 1109 ) is also thinner and more elongated and more pointed. FIG. 11 d shows a platinum electrode formed by the same method as was used in FIGS. 11 a , 11 b , and 11 c . The platinum electrode ( 1192 ) is more internal to the well formed by the silicon carbide, diamond-like coating, silicon nitride and silicon oxide in combination, titanium oxide, tantalum oxide, aluminum nitride, aluminum oxide or zirconium oxide and its titanium ring as was the electrode ( 1109 ) in FIG. 11 c . However it is less elongated and less pointed.
The platinum electrode is internal to the well formed by the silicon carbide, diamond-like coating, silicon nitride and silicon oxide in combination, titanium oxide, tantalum oxide, aluminum nitride, aluminum oxide or zirconium oxide and its titanium ring; said electrode whole angle at it's peak being in the range from 1° to 120°; the base of said conical or pyramidal electrode ranging from 1 micron to 500 micron; the linear section of the well unoccupied by said conical or pyramidal electrode ranging from zero to one-third.
A similar overall construction is depicted in FIG. 11 e . The electrode ( 1193 ), which may be platinum, is termed a mushroom shape. The maximum current density for a given metal is fixed. The mushroom shape presents a relatively larger area than a conical electrode of the same height. The mushroom shape advantageously allows a higher current, for the given limitation on the current density (e.g., milliamperes per square millimeter) for the chosen electrode material, since the mushroom shape provides a larger area.
Inductive Coupling Coils
Information transmitted electromagnetically into or out of the implanted retinal color prosthesis utilizes insulated conducting coils so as to allow for inductive energy and signal coupling. FIG. 12 b shows an insulated conducting coil and insulated conducting electrical pathways, e.g., wires, attached to substrates at what would otherwise be electrode nodes, with flat, recessed metallic, conductive electrodes ( 1201 ). In referring to wire or wires, insulated conducting electrical pathways are included, such as in a “two-dimensional” “on-chip” coil or a “two-dimensional” coil on a polyimide substrate, and the leads to and from these “two-dimensional” coil structures. A silicon carbide, diamond-like coating, silicon nitride and silicon oxide in combination, titanium oxide, tantalum oxide, aluminum nitride, aluminum oxide or zirconium oxide ( 1204 ) is shown acting as both an insulator and an hermetic seal. Another aspect of the embodiment is shown in FIG. 12 d . The electrode array unit ( 1201 ) and the electronic circuitry unit ( 1202 ) can be on one substrate, or they may be on separate substrates ( 1202 ) joined by an insulated wire or by a plurality of insulated wires ( 1203 ). Said separate substrate units can be relatively near one another. For example, they might lie against a retinal surface, either epiretinally or subretinally placed. Two substrates units connected by insulated wires may carry more electrodes than if only one substrate with electrodes was employed, or it might be arranged with one substrate carrying the electrodes, the other the electronic circuitry. Another arrangement has the electrode substrate or substrates placed in a position to stimulate the retinal cells, while the electronics are located closer to the lens of the eye to avoid heating the sensitive retinal tissue.
In all of the FIGS. 12 a , 12 b , and 12 c , a coil ( 1205 ) is shown attached by an insulated wire. The coil can be a coil of wire, or it can be a “two dimensional” trace as an “on-chip” component or as a component on polyimide. This coil can provide a stronger electromagnetic coupling to an outside-the-eye source of power and of signals. FIG. 12 c shows an externally placed aluminum (conductive) trace instead of the electrically conducting wire of FIG. 12 d . Also shown is an electrically insulating adhesive ( 1208 ) which prevents electrical contact between the substrates ( 1202 ) carrying active circuitry ( 1209 ).
Hermetic Sealing
Hermetic Coating
All structures, which are subject to corrosive action as a result of being implanted in the eye, or, those structures which are not completely biocompatible and not completely safe to the internal cells and fluids of the eye require hermetic sealing. Hermetic sealing may be accomplished by coating the object to be sealed with silicon carbide, diamond-like coating, silicon nitride and silicon oxide in combination, titanium oxide, tantalum oxide, aluminum nitride, aluminum oxide or zirconium oxide. These materials also provide electrical insulation. The method and apparatus of hermetic sealing by aluminum and zirconium oxide coating is described in a pending U.S. patent application Ser. No. 08/994,515, now U.S. Pat. No. 6,043,437. The methods of coating a substrate material with the hermetic sealant include sputtering, ion implantation, and ion-beam assisted deposition (IBAD).
Hermetic Box
Another aspect of an embodiment of the invention is hermetically sealing the silicon chip ( 1301 ) by placing it in a metal or ceramic box ( 1302 ) of rectangular cross-section with the top and bottom sides initially open ( FIG. 13 ). The box may be of one ( 1302 ) of the metals selected from the group comprising platinum, iridium, palladium, gold, and stainless steel. Solder balls ( 1303 ) are placed on the “flip-chip”, i.e., a silicon-based chip that has the contacts on the bottom of the chip ( 1301 ). Metal feedthroughs ( 1304 ) made from a metal selected from the group consisting of radium, platinum, titanium, iridium, palladium, gold, and stainless steel. The bottom cover ( 1306 ) is formed from one of the ceramics selected from the group consisting of aluminum oxide or zirconium oxide. The inner surface ( 1305 ), toward the solder ball, ( 1303 )) of the feed-through ( 1304 ) is plated with gold or with nickel. The ceramic cover ( 1306 ) is then attached to the box using a braze ( 1307 ) selected from the group consisting of: 50% titanium together with 50% nickel and gold. Electronics are then inserted and the metal top cover (of the same metal selected for the box) is laser welded in place.
Separate Electronics Chip Substrate and Electrode Substrate
In one embodiment of the invention ( FIG. 14 ), the chip substrate ( 1401 ) is hermetically sealed in a case ( 1402 ) or by a coating of the aluminum, zirconium, or magnesium oxide coating. However, the electrodes ( 1403 ) and its substrate ( 1404 ) form a distinct and separate element. Insulated and hermetically sealed wires ( 1405 ) connect the two. The placement of the electrode element may be epiretinal, while the electronic chip element may be relatively distant from the electrode element, as much distant as being in the vicinity of the eye lens. Another embodiment of the invention has the electrode element placed subretinally and the electronic chip element placed toward the rear of the eye, being outside the eye, or, being embedded in the sclera of the eye or in or under the choroid, blood support region for the retina. Another embodiment of the invention has the electronic chip element implanted in the fatty tissue behind the eye and the electrode element placed subretinally or epiretinally.
Capacitive Electrodes
A plurality of capacitive electrodes can be used to stimulate the retina, in place of non-capacitive electrodes. A method of fabricating said capacitive electrode uses a pair of substances selected from the pair group consisting of the pairs iridium and iridium oxide; and, titanium and titanium nitride. The metal electrode acts with the insulating oxide or nitride, which typically forms of its own accord on the surface of the electrode. Together, the conductor and the insulator form an electrode with capacitance.
Mini-capacitors ( FIG. 15 ) can also be used to supply the required isolating capacity. The capacity of the small volume size capacitors ( 1501 ) is 0.47 microfarads. The dimensions of these capacitors are individually 20 mils (length) by 20 mils (width) by 40 mils (height). In one embodiment of the invention, the capacitors are mounted on the surface of a chip substrate ( 1502 ), that surface being opposite to the surface containing the active electronics elements of the chip substrate.
Electrode/Electronics Component Placement
In one embodiment ( FIG. 16 a ), the internal-to-the-eye implanted part consists of two subsystems, the electrode component subretinally positioned and the electronic component epiretinally positioned. The electronics component, with its relatively high heat dissipation, is positioned at a distance, within the eye, from the electrode component placed near the retina that is sensitive to heat.
An alternative embodiment shown in FIG. 16 b is where one of the combined electronic and electrode substrate units is positioned subretinally and the other is located epiretinally and both are held together across the retina so as to efficiently stimulate bipolar and associated cells in the retina.
An alternative embodiment of the invention has the electronic chip element implanted in the fatty tissue behind the eye and the electrode element placed subretinally or epiretinally, and power and signal communication between them by electromagnetic means including radio-frequency (RF), optical, and quasi-static magnetic fields, or by acoustic means including ultrasonic transducers.
FIG. 16 c shows how the two electronic-electrode substrate units are held positioned in a prescribed relationship to each other by small magnets. Alternatively the two electronic-electrode substrate units are held in position by alignment pins. Another aspect of this is to have the two electronic-electrode substrate units held positioned in a prescribed relationship to each other by snap-together mating parts, some exemplary ones being shown in FIG. 16 d.
Neurotrophic Factor
Another aspect of the embodiment is the use of a neurotrophic factor, for example, Nerve Growth Factor, applied to the electrodes, or to the vicinity of the electrodes, to aid in attracting target nerves and other nerves to grow toward the electrodes.
Eye-Motion Compensation System
Another aspect of the embodiment is an eye-motion compensation system comprising an eye-movement tracking apparatus ( FIG. 1 b , 112 ); measurements of eye movement; a transmitter to convey said measurements to video data processor unit that interprets eye movement measurements as angular positions, angular velocities, and angular accelerations; and the processing of eye position, velocity, acceleration data by the video data processing unit for image compensation, stabilization and adjustment.
Ways of eye-tracking ( FIG. 1 b , 112 ) include utilizing the corneal eye reflex, utilizing an apparatus for measurements of electrical activity where one or more coils are located on the eye and one or more coils are outside the eye, utilizing an apparatus where three orthogonal coils placed on the eye and three orthogonal coils placed outside the eye, utilizing an apparatus for tracking movements where electrical recordings from extra-ocular muscles are measured and conveyed to the video data processing unit that interprets such electrical measurements as angular positions, angular velocities, and angular accelerations. The video data processing unit uses these values for eye position, velocity, acceleration to compute image compensation, stabilization and adjustment data which is then applied by the video data processor to the electronic form of the image.
Head Sensor
Another aspect of the embodiment utilizes a head motion sensor ( 131 ). The basic sensor in the head motion sensor unit is an integrating accelerometer. A laser gyroscope can also be used. A third sensor is the combination of an integrating accelerometer and a laser gyroscope. The video data processing unit can incorporate the data of the motion of the eye as well as that of the head to further adjust the image electronically so as to account for eye motion and head motion.
Physician's Local Control Unit
Another aspect includes a retinal prosthesis with (see FIG. 1 b ) a physician's local external control unit ( 115 ) allowing the physician to exert setup control of parameters such as amplitudes, pulse widths, frequencies, and patterns of electrical stimulation. The physician's control unit ( 115 ) is also capable of monitoring information from the implanted unit ( 121 ) such as electrode current, electrode impedance, compliance voltage, and electrical recordings from the retina. The monitoring is done via the internal telemetry unit, electrode and electronics assembly ( 121 ).
An important aspect of setting up the retinal color prosthesis is setting up electrode current amplitudes, pulse widths, and frequencies so they are comfortable for the patient. FIGS. 17 a - c and FIGS. 18 a - c illustrate some of the typical displays. A computer-controlled stimulating test that incorporates patient response to arrive at optimal patient settings may be compared to being fitted for eyeglasses, first determining diopter, then cylindrical astigmatic correction, and so forth for each patient. The computer uses interpolation and extrapolation routines. Curve or surface or volume fitting of data may be used. For each pixel, the intensity in increased until a threshold is reached and the patient can detect something in his visual field. The intensity is further increased until the maximum comfortable brightness is reached. The patient determines his subjective impression of one-quarter maximum brightness, one-half maximum brightness, and three-quarters maximum brightness. Using the semi-automated processing of the patient-in-the-loop with the computer, the test program runs through the sequences and permutations of parameters and remembers the patient responses. In this way apparent brightness response curves are calibrated for each electrode for amplitude. Additionally, in the same way as for amplitude, pulse width and pulse rate (frequency), response curves are calibrated for each patient. The clinician can then determine what the best settings are for the patient.
This method is generally applicable to many, if not all, types of electrode based retinal prostheses. Moreover, it also is applicable to the type of retinal prosthesis, which uses an external light intensifier shining upon essentially a spatially distributed set of light sensitive diodes with a light activated electrode. Ln this latter case, a physician's test, setup and control unit is applied to the light intensifier which scans the implanted photodiode array, element by element, where the patient can give feedback and so adjust the light intensifier parameters.
Remote Physician's Unit
Another aspect of an embodiment of this invention includes (see FIG. 1 b ) a remote physician control unit ( 117 ) that can communicate with a patient's unit ( 114 ) over the public switched telephone network or other telephony means. This telephone-based pair of units is capable of performing all of the functions of the of the physician's local control unit ( 115 ).
Physician's Unit Measurements, Menus and Displays
Both the physician's local ( 115 ) and the physician's remote ( 117 ) units always measure brightness, amplitudes, pulse widths, frequencies, patterns of stimulation, shape of log amplification curve, electrode current, electrode impedance, compliance voltage and electrical recordings from the retina.
FIG. 17 a shows the main screen of the Physician's Local and Remote Controller and Programmer. FIG. 17 b illustrates the pixel selection of the processing algorithm with the averaging of eight surrounding pixels chosen as one element of the processing. FIG. 17 c represents an electrode scanning sequence, in this case the predefined sequence, A. FIG. 17 d shows electrode parameters, here for electrode B, including current amplitudes and waveform timelines. FIG. 17 e illustrates the screen for choosing the global electrode configuration, monopolar, bipolar, or multipolar. FIG. 17 f renders a screen showing the definition of bipolar pairs (of electrodes). FIG. 17 g shows the definition of the multipole arrangements.
FIG. 18 a illustrates the main menu screen for the palm-sized test unit. FIG. 18 b shows a result of pressing on the stimulate bar of the (palm-sized unit) main menu screen, where upon pressing the start button the amplitudes A 1 and A 2 are stimulated for times t 1 , t 2 , t 3 , and t 4 , until the stop button is pressed. FIG. 18 c exhibits a recording screen that shows the retinal recording of the post-stimulus and the electrode impedance.
FIGS. 19 a , 19 b , and 19 c show different embodiments of the Physician's Remote Controller, which has the same functionality inside as the Physician's Local Controller but with the addition of communication means such as telemetry or telephone modem.
Patient's Controller
Corresponding to the Physician's Local Controller, but with much less capability, is the Patient's Controller. FIG. 20 shows the patient's local controller unit. This unit can monitor and adjust brightness ( 2001 ), contrast ( 2002 ) and magnification ( 2003 ) of the image on a non-continuous basis. The magnification control ( 2003 ) adjusts magnification both by optical zoom lens control of the lens for the imaging means ( FIG. 1 , 111 ), and by electronic adjustment of the image in the data processor ( FIG. 2 , 113 ).
While the invention herein disclosed has been described by means of specific embodiments and applications thereof, numerous modifications and variations could be made thereto by those skilled in the art without departing from the scope of the invention set forth in the claims. | The present invention is a motion compensation system for a visual prosthesis to adapt a visual image to movement of a user's eyes and head. The system includes a camera providing a video signal, an eye movement tracking device, a head movement tracking device, and a video processing unit processing the video signal and correcting the video signal for eye and head movement. The corrected video signal is sent to an implanted neural stimulator including electrodes stimulating visual neurons to create a perception of the video image. | 0 |
This is a continuation of co-pending application Ser. No. 577,044 filed on Feb. 6, 1984, now abandoned.
BACKGROUND OF THE INVENTION
This invention relates to transmitting digital symbols over a band-limited channel by modulating a carrier in accordance with a sequence of signals selected from an available signal constellation by a coding technique which introduces dependencies between signals in the sequence to increase immunity to noise (i.e., to achieve a so-called "coding gain" compared with an uncoded system).
Csajka et al., U.S. Pat. No. 4,077,021, and Ungerboeck, "Channel Coding with Multilevel/Phase Signals," IEEE Transactions on Information Theory, Vol. IT-28, No 1, January, 1982, incorporated herein by reference, disclose a coding system in which a conventional two-dimensional signal constellation having 2 N signal points (the number needed for simple mapping of symbols having N bits in an uncoded system in which no dependencies are introduced between signal points) is doubled in size to 2 N+1 signal points. An encoder introduces a degree of redundancy by adding one bit of information to each N-bit symbol, based on the state of a finite-state memory in the encoder, and the resulting N+1 bits for each symbol are mapped into one of the 2 N+1 possible signal points in the constellation. The signal points are organized into subsets which are disjointed (i e., have no signal points in common) and arranged so that the minimum distance between two signal points belonging to one subset is greater than the minimum distance between any two signal points in the constellation. The state of the finite state memory is arranged to depend on the subsets from which past signals were drawn. The encoder performs a coding function by using the state of the finite state memory as the basis for determining the subset from which each signal is to be drawn. Because this coding effectively permits only certain sequences of signals to be transmitted, each signal carries (in the form of the identity of the subset from which it is drawn) historical information which is exploited at the receiver to decode the sequence of received signals using a maximum likelihood sequence estimation technique (e.g., one based on the Viterbi Algorithm, as described in Forney, "The Viterbi Algorithm," Proceedings of the IEEE, Vol. 61, No. 3, March, 1973, incorporated herein by reference).
Another coding system, disclosed in copending patent application. U.S. Ser, No. 439,740, Forney, uses a signal constellation having more than 2 N but fewer than 2 N+1 signal points organized into two subsets which are partially overlapping and partially disjointed. A two-state encoder is arranged in such a way that on average only a portion of the sent signals carry historical information (i.e., include redundancy).
Another copending patent application, U.S. Ser. No. 485,069, U.S. Pat. No. 4,597,090 issued 6/24/86, Forney, shows systems in which the symbols to be sent are taken in groups, each having at least two symbols. Each group is encoded independently into a multi-dimensional point corresponding in turn to two or more two-dimensional signal points. The set of multi-dimensional points from which each multi-dimensional point may be drawn is independent of the two-dimensional signal points sent for any other group of symbols, but there is an interdependence among the signal points drawn for a given group.
SUMMARY OF THE INVENTION
In general the invention features, in one aspect, an improvement in a modulation system for sending digital symbols over a band-limited channel in accordance with a sequence of multi-dimensional points each composed of a plurality of two-dimensional modulation signal points, and each selected from an available alphabet of the multi-dimensional points by an encoder on the basis of a group of the digital symbols, the improvement including circuitry for accumulating the symbols of each group, and circuitry for thereafter selecting the multi-dimensional point for the group, and wherein the available alphabet includes a plurality of subsets of the multi-dimensional points and the subset from which the multi-dimensional point is selected for each group depends on the subset from which the multi-dimensional point is selected for another group.
In preferred embodiments the accumulating circuitry is arranged to add less than one bit per symbol interval of information about the dependencies among the selected multi-dimensional points (preferably no more than one-half bit per symbol interval); there is a decoder for deciding which multi-dimensional points were sent by applying a maximum likelihood sequence estimation technique to a sequence of multi-dimensional values received over the channel; the encoder includes a finite state device whose next state depends upon at least an earlier state of the device; there are a plurality of subsets of the two-dimensional signal points and the minimum squared distance in two-dimensional space between signal points from the same subset is greater than the minimum squared distance between any two signal points; each group comprises two symbols and the multi-dimensional point alphabet is four-dimensional; the finite state device has eight states; each symbol has 7 bits and there are 240 distinct two-dimensional signal points; the modulation system is a double side band--quadrature carrier system; there are four subsets of signal points; and there is circuitry for effecting 180 differential encoding of said symbols.
The system achieves a coding gain with a redundancy (in the preferred embodiments) of less than one bit per symbol interval.
Other advantages and features will be apparent from the following description of the preferred embodiment, and from the claims.
DESCRIPTION OF THE PREFERRED EMBODIMENT
We first briefly describe the drawings.
Drawings
FIG. 1 is a block diagram of a data transmitter;
FIG. 2 is a diagram of representative signal points on a signal point constellation;
FIG. 3 is a block diagram of the signal selection logic of FIG. 1;
FIG. 4 is a block diagram of the convolution encoder of FIG. 3;
FIG. 5 is a diagram of a portion of a state-transition trellis showing representative transitions between states;
FIG. 6 is a table of state transitions for the trellis of FIG. 5;
FIG. 7 is a block diagram of a data receiver;
FIG. 8 is a block diagram of the decoder of FIG. 7;
FIG. 9 is a table of contending metric calculations;
FIG. 10 is a table of surviving metric calculations;
FIG. 11 is a table of minimum weight code sequences;
FIG. 12 is a block diagram of the differential encoder of FIG. 3.
STRUCTURE AND OPERATION
Referring to FIG. 1, in transmitter 10 (a programmed microprocessor) an input bit stream 12 (appearing at a bit rate of, for example, 19,200 bits per second) is made up of a sequence of digital symbols each having the same number of bits (N). The symbols are taken two at a time by serial/parallel converter 14 to form groups 16 each having two symbols. N is selected (e.g. N=7) so that the number of bits (2N) in each group 16 is an integer. (But N need not be integral.) Each two-symbol group 16 is encoded by signal selection logic 18 into a pair of two-dimensional signals 20, which are used successively by modulator 22 for conventional DSB-QC modulation and transmission over channel 24 at a rate of 2400×8/7 baud, corresponding to 7 bits per modulation interval.
The encoding process can be viewed as first selecting for each two-symbol group 16 a single four-dimensional point (i.e., a multi-dimensional point of more than two dimensions) from an available alphabet of four-dimensional points in four-dimensional space (called 4-space), and then using the four coordinate values of the selected multi-dimensional point to specify the two pairs of coordinates of the two two-dimensional signal points.
Referring to FIG. 2, each signal is drawn from a two-dimensional constellation 30 having 240 signal points 31 (i.e., more than the 2 N =128 signal points required in an uncoded system but fewer than 2 N+1 =256 signal points). Each signal point 31 has odd integral coordinate values. All signal points 31 are grouped into four different subsets, respectively denoted (00), (01), (10), and (11), where for each subset the two bits in parentheses are respectively the least significant bits of the binary values of a and b taken from the following expression for the x and y coordinates of the signal:
(x, y)=(1+2a, 1+2b)
For example, signal point q has coordinates (x, y)=(11, 5), so that a=5=binary 101, b=2=binary 10. Thus, the least significant bits of a and b are a=1 and b=0, and signal point q is therefore in subset (10).
The complex signal plane can be viewed as being divided into 60 contiguous square sectors 32 each containing four signal points, one from each subset. Each quadrant of the plane contains 15 sectors, each identified by a value A n (n an integer between 1 and 15) where n generally reflects the relative distance of a sector from the origin (e.g., sector A 15 is farther from the origin than sector A 8 ).
The multi-dimensional points of the four-dimensional point alphabet similarly are categorized into 16 different multi-dimensional point subsets, each corresponding to a different combination of two signal point subsets. The multi-dimensional point subsets are respectively denoted (0000), (0001) . . . , the first two and final two bits of the value in parentheses being respectively the designations of the two signal point subsets to which the multi-dimensional point subset corresponds. For example, multi-dimensional point subset 0001 corresponds to signal point subsets (00) and (01).
Signal selection logic 18 is arranged to map each incoming two-symbol group comprising 14 bits (i 1 -i 14 ) into a multi-dimensional point which is then converted to two signals points.
Referring to FIG. 3, signal selection logic 18 includes convolutional encoder 40, amplitude coder 42, differential encoder 43, and multi-dimensional-point-to-signal-pair converter 39.
Convolutional encoder 40 takes incoming bits i 1 -i 3 (after manipulation in differential encoder 43) and adds a fourth redundancy bit, p, to give two two-bit values (called SET values) which correspond to the a and b values of the two different subsets from which the two signals are selected. The encoder thus introduces less than one bit per symbol of redundancy into the system, preferably no more than 1/2 bit per symbol. Bits i 4 -i 7 are passed (after manipulation in differential encoder 43) through to become the four bits constituting the two values (called QUAD values) for identifying the quadrants from which the two signals are selected. Amplitude coder 42 takes bits i 8 -i 14 and generates 2 values (called A values) which correspond to the sectors from which the two signals are selected.
The two SET values, two QUAD values, and two A values can be viewed as together specifying one of the 32,768 (i.e., 2 15 , where 15 is the number of bits (14) in the symbol group plus the one bit (p) added by encoder 40) possible multi-dimensional points in 4-space, which is then converted by converter 39 to a corresponding pair of signals. The 32,768 multi-dimensional points in the multi-dimensional point alphabet comprise those of the 57,600 four-dimensional points (each corresponding to a possible pair of two-dimensional signal points) which are closest to the origin in 4-space (i.e., require the least energy to send).
Referring to FIG. 4, convolutional encoder 40 includes four modulo 2 adders 43, 44, 46, 48, each connected to receive at least two of the three bits i 1 -i 3 and three delay (memory) elements 50, 52, 54 (each having a delay of two symbol intervals) connected to adders 42, 44, 46, 48 as shown. Encoder 40 generates the additional bit (p) in each group interval (where a group interval is two symbol intervals corresponding to a two-symbol group) based on the values of bits i 1 , i 2 , i 3 in the corresponding two-symbol group, and also based on the values of some of the bits i 1 , i 2 , i 3 in two-symbol groups which appeared in prior group intervals. Bits i 1 and i 2 become the SET value for the signal sent in the first symbol interval of each group interval, and bits i 3 and p become the SET value for the signal sent in the second symbol interval. Thus, the convolutional encoder implements a rate 3/4 code which adds 1/2 bit per modulation interval.
The memory elements 50, 52, 54 of convolutional encoder 40 effectively consist of a finite state device having eight possible states each represented by a three-bit value s 1 s 2 s 3 (where s 1 , s 2 , and s 3 are the respective states of elements 50, 52, 54) and each determined by the historical sequence of input bits i 1 , i 2 , and i 3 . The convolutional encoder in this way assures that the multi-dimensional point subset from which each multi-dimensional point is drawn depends on the multi-dimensional point subsets from which previous multi-dimensional points were drawn, and therefore carries historical information (by means of the 1/2 bit per symbol of redundancy) about the multi-dimensional point subsets of the preceding multi-dimensional points.
Encoder 40 is a finite state device which passes through a succession of states, the present state being separated in time from the previous state and also from the next state by a group interval.
For a given present state, only four of the eight next states are permissible. The other four of the eight next states are inherently impossible given the encoder's logic circuitry. Which next state occurs depends on the given present state and on which one of the eight possible combinations of i 1 i 2 i 3 bits is found in the current two-symbol group to be sent. For example, if the present state is 000 and the i 1 i 2 i 3 combination for the next two-symbol group is 000, the next state must be 000. In such a case, the two-symbol group is said to cause a transition from present state 000 to next state 000.
Referring to FIG. 5, a trellis 70 can be used to diagram all permissible transitions between present encoder states and next encoder states. The eight possible present states of encoder 40 are identified by a column of eight points (labeled (000), (001) . . . ) where the three bits in parentheses are the bits s 1 , s 2 , s 3 , representing the respective states of elements 50, 52, 54 in encoder 40. The possible next states (which occur one group interval later) are similarly labeled ((000), (001) . . . ).
The branches which connect the present states to the next states reflect the permissible state transitions. Each branch is labeled with four bits (e.g., 1111) the first three of which indicate the bits (i 1 , i 2 , i 3 ) of the current two-symbol group to be encoded, and the fourth of which indicates the p bit added by the encoder. Together the four bits labeling a given branch thus correspond to one multi-dimensional point subset.
There is a pair of branches leading from a particular present state to a permissible next state. The two branches in each pair correspond to multi-dimensional points whose multi-dimensional point subset bits are binary complements. For example, the only permissible transitions between state 000 and state 011 are represented by a pair of branches corresponding to type 0110 and type 1001 multi-dimensional points (0110 and 1001 being binary complements).
Referring to FIG. 6, there are a total of 64 possible transitions (corresponding to trellis branches) between the present states and the permissible next states. Only eight of the 64 possible transitions are shown in FIG. 5, namely those leading from present state 000.
Referring again to FIG. 5, the trellis represents a succession of permissible states spaced apart by group intervals and connected by permissible transitions. Only the states at two points in time are shown in FIG. 5 but the trellis is easily expanded to the left and right by simply repeating the columns of states and the pattern of permissible transitions.
Every permissible sequence of encoder states corresponds to a permissible path along a series of branches through the trellis. Every path in turn corresponds to a sequence of multi-dimensional point subsets corresponding to the branches which make up the path. Thus, in effect, the sequence of multi-dimensional point sent by the transmitter carries with it (in the form of the subsets of the multi-dimensional points sent) information about the encoder's path through the trellis.
As will be seen below, the receiver uses the received multi-dimensional values each corresponding to a pair of the received two-dimensional signals to estimate the encoder's original path through the trellis. Once the path is determined, the multi-dimensional points sent and hence the stream of symbols sent can be reconstructed.
Referring to FIG. 7, in receiver 100 (a programmed microprocessor), the noise affected modulated carrier received from channel 24 is passed through demodulator 102 and signal processor 104 to produce a stream of received two-dimensional signals. Decoder 106 considers the stream of received two-dimensional signals as a stream of received multi-dimensional values and decides which multi-dimensional points (and hence which symbols) were sent by means of a so-called maximum likelihood sequence estimation technique using the Viterbi algorithm discussed in the Forney article.
In general, the decoding process involves first determining which path through the trellis is most likely to have been the one followed by the encoder. Once that maximum likelihood path is found, the sequence of multi-dimensional point subsets corresponding to that path (called the maximum likelihood path history) is used together with the sequence of received multi-dimensional values to decide which multi-dimensional points were sent from among the multi-dimensional point subsets representing the maximum likelihood path history.
The maximum likelihood path is determined by finding which permissible sequence of multi-dimensional point subsets (i.e., which trellis path) is closest (measured in aggregate squared distance in 4-space) to the sequence of received multi-dimensional values. The distance (called a branch metric) between a received multi-dimensional value and a permissible multi-dimensional point from a subset corresponding to a branch of the trellis is simply the squared distance between them in 4-space. The distance (called a path metric) between a received multi-dimensional value sequence and a permissible sequence of multi-dimensional points from subsets corresponding to a permissible trellis path is simply the arithmetic sum of the squared distances between each of the received multi-dimensional values in the sequence and the corresponding multi-dimensional points along the path.
The decoding process steps are repeated in each group interval. Because the decoding depends on analysis of a sequence of received multi-dimensional values, the decision of which multi-dimensional point was sent in a particular interval must be delayed for a number of group intervals until the probability of error in estimating the most likely trellis path is acceptably small.
For a given group interval, the first decoding step is to find the one multi-dimensional point in each subset which is closest to the received multi-dimensional value. This step alone reduces from 32,768 to 16 the number of contending multi-dimensional points for that interval.
Referring to FIG. 8, this is done by passing the received multi-dimensional value through slicer 108 which performs two conventional slicing operations on the multi-dimensional point alphabet in each of four dimensions in the vicinity of the received multi-dimensional value.
Next, in branch metric calculator 110, the squared distance between each received multi-dimensional value and each of the sixteen contending multi-dimensional points is computed. These squared distances are denoted d 2 (0000), d 2 (0001) . . . where the value in parentheses indicates the multi-dimensional point subset. For example, the value d 2 (0000) is the squared distance between the received multi-dimensional value and the contending multi-dimensional point in the 0000 subset.
Recalling that each present state and each corresponding permissible next state in the trellis are connected by a pair of branches corresponding to two different subsets of multi-dimensional points, and that there is only one most likely path through the trellis, only one branch of each pair of branches can lie on the maximum likelihood path. Thus, it is possible at this stage to reduce by half the number of contending branches simply by determining which branch of each pair represents the multi-dimensional point subset which is closer to the received multi-dimensional value.
To do this, branch metric calculator 110 determines as a so-called branch pair metric for each branch pair, denoted, e.g., b(000), the smaller of the previously determined branch metrics corresponding to the two branches in the pair. For example b(000)=min[d 2 (0000), d 2 (1111)], b(00l)=min [d 2 (0001), d 2 (1110)] . . .
The next step (performed by contending metric calculator 112) is to take the branch pair metric leading from each present state and add it to a so-called normalized surviving metric of that present state (determined in the manner described below) to obtain a so-called contending metric.
Referring to FIG. 9, the eight surviving metrics are denoted m(000), m(001) . . . where the value in parentheses denotes a present state. The 32 contending metrics are denoted m(000,000), m(000,001). . . where the values in parentheses denote a present state and a permissible next state.
There are four contending branches leading into each next state but only one can be in contention against the contending branches leading into the other next states, namely the one whose branch pair metric combined with the surviving metric of the present state from which the branch leads, produces the smallest contending metric.
Referring to FIG. 10, the smallest contending metric for each next state is determined by simple comparisons, each yielding a surviving metric denoted, e.g. , m(000), where the value in parentheses corresponds to the new state.
Of the eight surviving branches to the eight next states, only one is part of the maximum likelihood path, namely the one for which the surviving metric has the minimum value.
This minimum surviving metric (m(min)) is found (by minimum metric calculator 116, FIG. 8) from among the eight surviving metrics, i.e., m(min)=min[m(000), m(001), m(010), m(011), m(100), m(101), m(110), m(111)].
Finally, the minimum metric is subtracted from each of the normalized surviving metrics (by normalized surviving metric calculator 118, FIG. 8) to prevent the normalized surviving metrics from growing without bound.
This minimum surviving metric for the next group interval thus represents the minimum path metric through the trellis corresponding to the historical sequence of received multi-dimensional values. The decoder has thus determined the maximum likelihood path of the encoder through the trellis.
The next step is to determine the corresponding sequence of sent multi-dimensional points. For each of the eight possible present states, decoder 106 stores a so-called present surviving path history identifying the sequence of multi-dimensional points which correspond to the surviving path leading to each present state. When the eight surviving metrics for the eight possible next states are calculated, the decoder creates a next surviving path history for each next state. Each next surviving path history contains the multi-dimensional point corresponding to the surviving metric leading to each next state plus the sequence of past multi-dimensional points of the corresponding present surviving path history.
The next surviving path history which corresponds to the minimum surviving metric contains the sequence of multi-dimensional points which is the best estimate at that time of the sequence of multi-dimensional points sent.
In a given surviving path history the multi-dimensional points which are many group intervals old are more likely to be correct than more recent multi-dimensional points. The decision of which multi-dimensional point was sent in a given group interval is made after the passage of a predetermined number of group intervals (e.g., 16) selected such that the probability of error is acceptably low.
The coding gain produced by the described coding system depends on the error probability and on the average energy required to send the two-dimensional signal points.
The error probability can be determined by first considering the output of the encoder as a bit stream
i.sub.1.sup.(1) i.sub.2.sup.(1) i.sub.3.sup.(1) p.sup.(1) i.sub.1.sup.(2) i.sub.2.sup.(2) i.sub.3.sup.(2) p.sup.(2) . . . i.sub.1.sup.(N) i.sub.2.sup.(N) i.sub.3.sup.(N) p.sup.(n)
where, e.g., i 2 .sup.(2) is the value of output bit i 2 for the second group interval. It is then possible to determine as a so-called impulse response the string of those output bits of encoder 40 which will have "1" values (as determined by the logic of encoder 40) when a single predetermined input bit has a "1" value. For example, the impulse response resulting from only bit i 1 having a "1" value for the first group interval can be represented by the impulse response
i.sub.1.sup.(1) p.sup.(1) p.sup.(2) p.sup.(3)
meaning that i 1 .sup.(1) =p.sup.(1) =p.sup.(2) =p.sup.(3) =1. Similarly the impulse responses respectively resulting from i 2 .sup.(1) =1 and i 3 .sup.(1) =1, are
i.sub.2.sup.(1) p.sup.(1) p.sup.(3) p.sup.(4)
i.sub.3.sup.(1) p.sup.(1) p.sup.(2) p.sup.(4)
All other possible bit sequences (called code sequences) are shifts and linear (mod 2) combinations of the three impulse responses.
The difference (mod 2 sum) between any two code sequences is another code sequence, and therefore, the minimum Hamming distance between any two code sequences generated by encoder 40 is the minimum number of 1 values (called the minimum weight) in a non-zero code sequence. Because the impulse responses each have weight 4, which is even, the minimum Hamming distance must be either 2 or 4. However, no linear combination of the impulse responses has weight 2, so the minimum distance must be 4.
Referring to FIG. 11, there are 22 distinct minimum weight code sequences.
Thus, the minimum noise energy required to cause an error in decoding is 4d 0 2 , where 2d 0 is the minimum distance between any two two-dimensional signal points (i.e., d 0 is the distance from a two-dimensional signal point to the nearest decision boundary in two-dimensional space.) Such an error could occur in the direction of any of the 22 distinct minimum weight code sequences of FIG. 11, in each case in any of sixteen ways per group interval. In addition, the 4d 0 2 noise energy could cause an error between neighboring multi-dimensional points in a single subset in any one of eight different ways in each group interval. Thus, the union bound of error probability per group interval is 22 times 16 plus 8 equals 360Q(2d 0 ). Simulations suggest that this union bound is conservative by a factor of 2 so that the error probability per symbol interval is approximately 90Q(2d 0 ) compared with 4Q(d 0 ) for an uncoded system.
Using the rule of thumb that in the error rate region of interest, every factor of 2 in increased error rate corresponds to a cost of 0.2 db in signal-to-noise ratio, the error coefficient penalty for the described coding system is 0.9 db compared with an uncoded system.
The 4d 0 2 minimum noise energy for the coded system gives a 6 db gross coding gain over uncoded systems (which have a d 0 2 minimum noise energy), which is offset not only by the 0.9 db loss from increased error probability, but also by the additional 1.5 db needed to send the extra bit (p) per group interval which the encoder adds to the original 14 bits of each two-symbol group. Thus, the net coding gain is 6 db-1.5 db-0.9 db=3.6 db.
Referring to FIG. 12, differential encoder 43 includes modulo 2 summers 120, 122, 124, 126, 128, 130, 132, and delay element 134 (representing a one group interval delay) which together convert incoming bits i 1 through i 7 to differentially encoded bits i 1 through i 7 . Bits i 1 and i 2 are the SET bits for the first symbol interval in each group interval. Bit i 3 , together with bit p are the SET bits for the second symbol interval. Bits i 4 , i 5 and i 6 , i 7 are respectively the QUAD bits for the first and second symbol intervals. (The assignments of QUAD bits to quadrants are shown on FIG. 2.)
The differential encoder effectively complements the SET and QUAD bits of the signal point to be sent if the previous signal point was in the bottom half-plane (i.e., had 1 as its first QUAD bit). The complementing is accomplished by delivering the output of delay element 134 to summers 124, 126, 130, 132. Because i 1 i 2 i 3 are complemented, the parity bit (p) is also complemented. The A bits remain unchanged so the pair of resulting signal points is 180° out of phase with the pair that would have been generated had i 6 been 0 in the previous group interval.
At the receiver, the reverse process is performed at the output of decoder 106, ensuring that a 180° phase reversal on the channel will cause only a momentary error in the decoded symbols.
Other embodiments are within the following claims. | In a modulation system for sending digital symbols over a band-limited channel in accordance with a sequence of multi-dimensional points each composed of a plurality of two-dimensional modulation signal points, and each selected from an available alphabet of the multi-dimensional points by an encoder on the basis of a group of the digital symbols, the improvement which includes circuitry for accumulating the symbols of each group, and circuitry for thereafter selecting the multi-dimensional point for the group, and in which the available alphabet includes a plurality of subsets of the multi-dimensional points, and the subset from which the multi-dimensional point is selected for each group depends on the subset from which the multi-dimensional point is selected for another one of the groups. | 7 |
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application claims priority from U.S. provisional application No. 60/481,661 which was filed on Nov. 18, 2003, which is incorporated by reference as if fully set forth.
BACKGROUND OF THE INVENTION
[0002] The Self-storage industry has become an important aspect of everyday life. Self storage facilities proliferate this country's landscape and can be found all over the world. Self storage facilities provide a rentable semi-permanent solution to store all kinds of things. They are user friendly and provide easy twenty-four hour, seven days a week access to the client's stored stuff.
[0003] A Self-storage facility comprises a plurality of individual storage units enclosed by a secured perimeter. A typical arrangement has the storage unit with a lockable garage type door attached to a shed-like structure. The self storage unit's garage type door allows for access to the interior of the storage unit and the locking mechanism secures the door member in a locked position. In addition, the door may have an alarm or some type of indicating device which sends notice to a system controller that that door is open or closed.
[0004] The secured perimeter typically includes a fence or barrier surrounding the storage facility having at least one gate for ingress and egress. The gate restricts access to only those individual clients who have proper clearance or authorization to enter the storage facility. For example, an electronic gate controller is programmed to only allow access to individual customers who have their rents paid up to date.
[0005] Storage units are usually rented for various periods of time to accommodate the needs of the client. The renting of the individual storage unit is typically accomplished by someone physically manning each storage facility with an attendant. This attendant conducts the transactions necessary with potential and current customers. The Patriot Act in conjunction with moststate statutes makes it mandatory to have a person present to check each renter's credentials before renting them a storage unit.
[0006] A problem can occur while the attendant is giving a tour of the facility to a potential client. While the attendant is away, no one is at the self storage facility's office to watch the video monitor(s) or alarm(s). If some nefarious activity occurs, no one is present to view it. A second attendant could be added to aide the first attendant, but this increases the overhead costs associated with operating the self storage facility.
[0007] Additionally, while the attendant is busy, he or she will not be able to monitor ingress or egress of the storage facility. While a camera and a video recorder can watch and record the self storage facility's activities, there is no way to link activity to the video recorder. For example, when someone at an entrance keypad enters an invalid access code to open a front gate, the attendant may be away. There is no accurate way to determine what happened at the keypad from the recorded video even though an event log was generated by a system controller. This is because the recorded video is not linked to the storage facility's system controller. The system controller is a free standing microprocessor based system which monitors and operates the gates and the open-closed alarms on the individual storage units. System controllers in use only have a parallel portto print out an activity log to a dot matrix printer and there is no physical link between the system controller and the video monitoring system.
[0008] Therefore a need exists to display system controller activity onto a display monitor. There is even a greater need to collect the system controller's event log data to a database and allow searching by time, by event, by camera or by a change in display. A change in display occurs when a video system detects any change in an image and tells the video recorder to start recording.
SUMMARY
[0009] The present invention translates event report data from a self storage facility's system controller and displays it on a video monitor. The video monitor is usually connected to at least one camera which monitors the self storage facility. In addition, the translated event report data can be stored in a searchable database for later look-ups and cross-referencing. The invention will be further able to filter the system controller's event report by fields and route appropriate data to an appropriate video overlay which corresponds to an area where the event occurred, thereby providing necessary correlation between the recorded video and the occurring events.
BRIEF DESCRIPTION OF THE DRAWING(S)
[0010] FIG. 1 shows a block diagram of one aspect of the present invention.
[0011] FIG. 2 shows a block diagram shows a second aspect of the present invention
DETAILED DESCRIPTION
[0012] The present invention will be described with reference to the drawing figures wherein like numerals represent like elements throughout.
[0013] The present invention can be first utilized in a self storage environment where a system controller has a printer output or any output which produces a log of system controller's events. The system controller can have a printer port, a serial port, an USB port, a fire wire or any other type of communications link.
[0014] The event data may be first converted to another format which is more amenable to travel over distances. Referring to FIG. 1 , the event data comes from the system controller 100 and is applied to a data converter 102 . The data converter 102 applies the converted data to the text inserter 104 which overlays text from a monitoring camera 106 and displays it on a monitor 108 . The output of the text inserter may also be applied to a video recorder for later play back, this first aspect of the present invention does not include event searches.
[0015] For example, a customer enters a wrong entrance code into the front gate controller keypad. The denied access information which is produced by the system controller 100 indicates that an erroneous access code was entered by a customer. The keypad and its location, along with a time stamp are sent by the system controller 100 to an output port as event data. The event data is converted to overlay text video by text inserter 104 and displayed on a monitor 108 .
[0016] Referring to FIG. 2 , another embodiment has the event data from a second system controller 200 sent to a text inserter 202 . The output of the text inserter is applied to the video recorder 204 . The event data is also sent to a searchable database 206 . The video recorder 204 and the searchable database 206 may or may not be the same computer. This combination of searchable database 206 and video recorder 204 allows events to be searchable by time, event type, customer or any database field.
[0017] For example, a customer enters a wrong entrance code into the front gate controller keypad. The denied access information which is produced by the system controller 200 indicates that an erroneous access code was entered by a customer. The keypad and its location, along with a time stamp are sent by the system controller 200 to an output port of the system controller 200 as event data. The event data is converted by text inserter 202 and the camera video is overlaid with text information from the system controller 200 and displayed on a monitor and or stored in a video recorder 204 . In addition, the event data is sent and stored to a searchable database 206 . The information is then searchable by field or combination of fields. The attendant will be able to request a video image along the time and trouble code. This information is extremely important when a crime was committed at the self storage facility and one or more law enforcement agencies are on the scene needing information.
[0018] In yet another embodiment, the video and event data may be stored on different computers. A first computer has the event data database and the second has the digital video recorder. Through the use of database transactional calls from a program on the digital video recorder to the database computer the two computers will act seamlessly to the end user as the requested information is displayed on the computer which is running a monitoring program.
[0019] In still yet another embodiment, three or more computers may be used to store the searchable database, the digital video and to run a computer program which executes instructions to request the event data and video data for certain date and time stamps.
[0020] In still yet another embodiment, the event data from the system controller is applied directly to the computer with the video recorder. This allows the more efficient use of resources. The computer will internally overlay the video text by making appropriate calls to the video card through the computers operating system. It may necessary with some system controllers to convert its parallel output to a computer friendlier format such as serial or USB.
[0021] In another embodiment, the system controller may be incorporated into the computer, such as an IBM PC running windows, dos, unix or Linux. The computer may also be of the Apple variety. This can be accomplished through the use of video multiplexing (mux) cards and the computers input and output (i/o). The computer can even be linked via USB for example, to a system controller type box to isolate the physical wiring away from the computer. | The present converts the printer output data from a system controller utilized at a self storage facility and displays it on a monitor. The monitor is usually connected to a camera which monitors the self storage facility. In addition, the converted output data can be recorded by a digital video recorder, which records camera video. The printer data can be placed into a searchable data base. | 7 |
BACKGROUND OF THE INVENTION
[0001] The present invention relates to a high-speed electrical data transmission system. The invention relates more particularly, although not exclusively, to a cost-effective system for electrically transmitting data in local area computer networks and other communications networks.
[0002] Modern methods of transmitting data signals by cable include fibre-optic communication, Low Voltage Differential Signalling (LVDS) and single ended signalling.
[0003] Fibre-optic systems are presently used to achieve high-speed data transmission over long distances. For example, high-speed broadband Internet and pay-TV networks and telephone networks have employed this technology. However, due to high costs of fibre-optic transceivers, the difficulty of splicing fibre-optic cables and the inability to convey electrical power in addition to data signals, fibre-optic networks have not extended the whole way to each end-connection point such as home or office modems, telephones or pay-TV receivers. Rather, the fibre-optic network extends to a fibre-optic transceiver “node” or “hub” employing optical-to-electrical (and vice versa) signal conversion and from which an electrical network extends to the various points of connection. For example, the signal from a fibre-optic transceiver having been converted into electrical voltage-fluctuation signals is connected by electrical cables to appliances such as home computers, telephones and pay-TV receivers in private premises and offices for example. For this reason, data signal from the fibre-optic transmission line to individual premises is by converting the optical signal into an electrical signal in a shared fibre-optic transceiver. The electrical signal is conveyed by LVDS transmission lines to electrical appliances such as personal computers (say in a local area network), telephones, cable televisions etc.
[0004] Although there have heretofore been disadvantages in the implementation of electrical cables from the transceiver to the various endpoints—particularly associated with cable length restrictions, there are advantages in adopting electrical cabling to transfer data and these include lower cable cost, ease of splicing electrical cables and the presence of existing in situ cable networks. Although LVDS transmission has replaced single-ended signalling transmission as it provides a higher data transfer rate and better resistance to electromagnetic interference, LVDS systems remain susceptible to electromagnetic interference and signal degradation over extended cable lengths.
OBJECTS OF THE INVENTION
[0005] It is an object of the present invention to overcome or substantially ameliorate at least one of the above disadvantages and/or more generally to provide an improved, cost-effective high-speed electrical data transmission system.
DISCLOSURE OF THE INVENTION
[0006] There is disclosed herein a high-speed electrical data transmission system, comprising:
a first signal mixer for receiving high-speed data and comprising means for converting said data into an electrical current-fluctuating data signal; and a first signal processor located remotely of the first signal mixer and connected electrically thereto for receiving the current-fluctuating data signal and comprising means for converting the current-fluctuating data signal into a voltage-fluctuating data signal.
[0009] Preferably, the system further a cable comprising only two operative conductors connected between the first signal mixer and the first signal processor for carrying said current-fluctuating data signal.
[0010] Preferably, the system further comprises:
a transceiver located between the first signal mixer and an external network, the transceiver communicating a voltage-fluctuating data signal to the first signal mixer; a second signal processor providing a voltage-fluctuating data signal to the transceiver.
[0013] Preferably, the voltage-fluctuating data signal provided by the first signal processor at said remote location is connected electrically to a network of one or more appliances, and wherein the system further comprises:
a second signal mixer at said remote location providing a current-fluctuating data signal and being connected electrically with said second signal processor for conversion of the current-fluctuating data signal thereby into said voltage-fluctuating data signal presented to the transceiver.
[0015] Preferably, the transceiver is a fibre-optic transceiver and wherein the external network is a fibre-optic network.
[0016] The present invention can convey high bandwidth data at a rate comparable to that of fibre-optic systems, yet has the cost advantage and ease of splicing advantage of LVDS systems without susceptibility to signal degradation to which the latter is prone. Furthermore, the present system can carry electrical power in addition to data transmission.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] A preferred form of the present invention will now be described by way of example with reference to the accompanying drawings, wherein:
[0018] FIG. 1 is a schematic block diagram depicting a high-speed electrical data transmission system communicating data between a fibre-optic cable and a local network;
[0019] FIG. 2 is a schematic circuit diagram of the one of the signal mixers and one of the signal processors connected to one another by a two-conductor transmission line cable;
[0020] FIG. 3A is a graph showing a voltage signal waveform at the base of transistor Q 1 in the signal mixer of FIG. 2 ;
[0021] FIG. 3B is a graph showing the current signal waveform in the transmission line; and
[0022] FIG. 3C is a graph showing the voltage output waveform of the amplifier U 1 of the signal processor shown in FIG. 2 .
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0023] The block diagram of FIG. 1 depicts high-speed electrical data transmission system 10 communicating data between a fibre-optic public cable network 11 and a home or office local area network including for example a cable television receiver 19 , home automation appliances 20 , a telephone 21 and a personal computer 22 . Of course some of these features could be omitted and others added. In an office local area network, the various components might include a computer server, numerous workstations, photocopiers, fax machines and the like.
[0024] The fibre-optic cable 11 would typically extend under the street or footpath and service numerous offices and/or premises. At each residence or office building for example, there is provided a fibre-optic transceiver 12 which converts optical data signals into electrical data signals.
[0025] Connected electrically to the transceiver 12 is a signal mixer 13 and signal processor 14 . A two-conductor cable or “transmission line” 15 extends from the signal mixer 13 to a signal processor 17 inside the premises. The signal processor 17 would typically be housed in a plastics casing similar in style to an “external modem” or “broadband modem/hub”. To enable duplex data transmission, the fibre-optic transceiver is connected electrically with another signal processor 14 which is in turn connected by a two-conductor transmission line cable 16 to another signal mixer 18 alongside signal processors 17 . Signal processor 17 would typically be housed in the same “external modem” style housing and perhaps be integrated onto the same printed circuit board as signal processors 17 . Indeed, signal mixer 13 and signal process 14 might also be integrated onto the same printed circuit board.
[0026] The signal mixer 13 converts a voltage-fluctuating signal from the fibre-optic transceiver into a current-fluctuating signal for transmission along the transmission line 15 . The signal processor 17 detects current fluctuations in transmission line 15 and converts this back to voltage fluctuations. The voltage waveform produced by signal processor 17 matches the original voltage waveform communicated from the fibre-optic transceiver 12 to the signal mixer 13 . From signal processor 17 , the voltage fluctuation waveform is conveyed via the local network to the various components 19 - 22 .
[0027] Furthermore, and in order to facilitate duplex communication, the electrical appliances or components and 19 - 22 transmit voltage-fluctuation signals to the signal mixer 18 which functions the same way as signal mixer 13 —converting voltage fluctuations into current fluctuations for transmission along transmission line 16 to signal processor 14 for communication with the outside fibre-optic network via fibre-optic transceiver 12 .
[0028] As a further extension of the invention, the home computer 22 can be connected to another signal processor/signal mixer pair 23 , 24 for communication via a pair of electrical transmission lines 25 and 26 to a distant remote location whereat a further signal mixer/signal processor pair 27 , 28 is connected to another computer 29 . For example, appliances 19 - 22 might be located at the fifth floor of a high-rise office building, and the transmission lines 25 and 26 could extend to the twentieth floor of the same building whereat signal mixer 27 , signal processor 28 and computer 29 are located.
[0029] FIG. 2 is a detailed schematic wiring diagram of one of the signal mixers 13 , 18 , 27 and one of the signal processors 14 , 17 , 28 . The signal mixer receives DC power from an AC-to-DC power supply adapter or might alternatively receive DC supply voltage from an electrical appliance. The block identified as U 4 is a parallel-to-serial semiconductor IC used to convert parallel input signals into serial signals emitted through resistor R 6 to the base of transistor Q 1 . Transistor Q 1 converts the voltage signals into electrical current signals and sends these through the two-conductor transmission line 15 , 16 , 25 , 26 as the case may be.
[0030] At the signal processor the current-fluctuation signal passes through resistor R 7 to ground and the amplifier U 1 receives the current fluctuations ahead of resistor R 7 via resistor R 4 . The amplifier U 1 converts the transmission line current-fluctuation signal into a voltage-fluctuation signal and passes this via resistor R 1 to the block identified as U 2 which comprises a serial-to-parallel semiconductor IC for reversion of serial signals to parallel signals.
[0031] As will be appreciated by reference to FIGS. 3A , 3 B and 3 C, the current signalling system of the present invention will produce a current signal waveform at the target end of the transmission line that is almost identical to the current waveform at the source. Line capacitance and inductance will affect a current signal waveform minimally and this compares favourably with degradation in the voltage waveform in LVDS systems resulting from line resistance and susceptibility to electromagnetic interference for example. An LVDS network having for example a 5V input at 100 mA and a line resistance of 10 ohms. The receiving end of the line will have a voltage amplitude of 4V representing a voltage distortion of 20%. With the present system of current signalling, a current of 100 mA at the sending end of the transmission line will present 100 mA (or a figure negligibly varied therefrom) at the target end of the transmission line—representing zero or negligible distortion. Furthermore, the present system has very high resistance to electromagnetic interference perceived by the transmission line itself. Indeed if a transmission line in an LVDS system is placed in close proximity to an AC motor supply line, the voltage signal waveform of the line suffers drastic distortion resulting from high back EMF from the motor winding.
[0032] Experimentation has shown that the transmission line of the present system suffers no detriment when placed in close proximity to a running AC motor. Furthermore, as the current signalling system of the present invention is less affected by line impedance, the signal waveform becomes less distorted compared with LVDS transmission. As a result, the choice of cable type for transmission line cabling adopted in the present system is left wide open. Even inexpensive Cat 1 cable (bell cable) can be used. For best performance however, the impedance of the cable should match or closely match the output impedance of the signal mixer and the input impedance of the signal processor.
[0033] It should be appreciated that modifications and alterations obvious to those skilled in the art are not to be considered as beyond the scope of the present invention. For example, the system is certainly not limited to connection to a fibre-optic transceiver. As coaxial cabling is also widely used to distribute signals over large distances. | A high-speed electrical data transmission system ( 10 ) includes a signal mixer ( 13 ) for receiving high-speed data from external network transceiver ( 12 ). The signal mixer ( 13 ) converts the data into an electrical current-fluctuating data signal. A signal processor ( 17 ) is located remotely of the signal mixer ( 13 ) and is connected electrically thereto by a simple/inexpensive cable ( 15 ) having only two operative conductors and receives the current-fluctuating data signal via the cable ( 15 ). The signal processor ( 17 ) converts the current-fluctuating data signal into a voltage-fluctuating data signal for distribution to a local area network. | 7 |
CROSS-REFERENCE TO RELATED APPLICATION
This application claims priority to British Patent Application No. 1004260.4, filed Mar. 15, 2010, which is incorporated herein by reference in its entirety.
TECHNICAL FIELD
The technical field relates to a method for diagnosing a fault in a fuel injection system of an internal combustion engine, typically a Diesel engine, of a motor vehicle.
BACKGROUND
In order to comply with tighter emission regulations, the motor vehicle must be provided with an On Board Diagnostic (OBD) system, for checking the proper operation of the vehicle sub-systems that can affect the polluting emissions. Since the polluting emissions strongly depend on the quality of the fuel combustion into the engine cylinders, the regulations generally require the OBD system to detect also the malfunctions of the engine fuel injection system.
The fuel injection system of modern Diesel engines comprises at least a fuel injector per engine cylinder, and a fuel pump that draws the fuel from a tank and delivers it in pressure to a fuel rail connected with all the fuel injectors. The fuel injectors are generally governed by an engine control unit (ECU) according to a multi-injection pattern, which provides for each fuel injector to perform a plurality of injection pulses per engine cycle.
Each injection pulse is characterized by an individual quantity of fuel to be injected, and by a timing at which said individual quantity of fuel must be injected. The injection timing depends on the instant at which the ECU commands the fuel injector to open, also referred as Start Of Injection (SOI), which can be expressed in temporal term as well as in term of angular position of the engine crankshaft. The individual fuel quantity depends on the opening time of the fuel injector, namely the time between the instant at which the ECU commands the fuel injector to open (SOI) and the instant at which the ECU commands the fuel injector to close, also referred as Energizing Time (ET). If a malfunction of the fuel injection system arises, the individual fuel quantity actually injected by each injection pulse may not correspond to that expected in response of the respective energizing time.
In order to overcome this drawback, most ECU implements a compensation strategy that automatically correct the energizing time of each injection pulse, in order to actually achieve a desired individual fuel quantity. Nevertheless, a malfunction of the fuel injection system may also cause the timing of each injection pulse to drift with respect to that expected.
This injection timing fault is particularly due to damages occurred by the mechanical devices driving the fuel injector, to errors of the ECU computing, or to injection drifts caused by production spread or aging of the fuel injectors. Since the injection timing has a very strict relationship with the quality of the combustion within the engine cylinders, wrong injection timing can cause the polluting emissions to exceed the maximum levels set by the regulation.
As a consequence, this regulation generally provides for the OBD system to detect a malfunction of the fuel injection system when the system is unable to deliver fuel at the proper crank angle/timing (e.g. injection timing too advanced or too retarded) necessary to maintain a vehicle's NMHC, CO, NOx, and PM emissions at, or below, an applicable emission level. In order to fulfill this requirement, a known solution uses the energizing time corrections that are determined by the above mentioned compensation strategy, and detects the malfunction of the fuel injection system when said energizing time corrections exceed a calibrated threshold.
In greater detail, the known solution provides for commanding an injection pulse to inject a desired fuel quantity, for monitoring the energizing time actually used for injecting said desired fuel quantity, and for generating an alert signal if the difference between the actual energizing time and the expected energizing time exceeds the above mentioned threshold. As a matter of fact, this known solution is based on the assumption that, when the energizing time corrections are too great, the fuel injection system is malfunctioning to the point that also the injection timing is suspected to drift.
However, this assumption represents the major deficiency of this known solution, because actually there is not an immediate and necessary relationship between energizing time, injection timing and combustion quality.
In view of the above, it is at least one object to provide an improved method for detecting injection timing faults of a fuel injection system. Another object of the present invention is to achieve the above mentioned goal with a simple, rational and rather inexpensive solution. In addition, other objects, desirable features and characteristics will become apparent from the subsequent summary and detailed description, and the appended claims, taken in conjunction with the accompanying drawings and this background.
SUMMARY
An embodiment provides a method to diagnose a fault in a fuel injection system of an internal combustion engine, comprising the steps of commanding an injection pulse for injecting a test quantity of fuel into an engine cylinder, of determining the torque released to an engine crankshaft due to a combustion of said injected fuel quantity, of calculating the difference between this torque and an expected value for said torque, and of diagnosing a fault in the fuel injection system if said difference exceeds a threshold value.
This strategy is based on the assumption that the torque released to the crankshaft is strongly affected by the quality of the combustion within the engine cylinders, which in turn has a very strict relationship with the injection timing, so that there is an immediate and necessary relationship also between the injection timing and the released torque. As a consequence, this new strategy provides a more reliable way to detect whether the fuel injection system is able to provide the desired injection timing.
According to an embodiment, the expected value is determined through an empirically determined map correlating the expected value with one or more engine operating parameters, such as for example engine speed, intake air mass flow, injected fuel quantity and other. This embodiment has at least the advantage that the map can be determined with an experimental activity and then stored in a data carrier, thereby simplifying the diagnosis of the injection system faults.
According to another embodiment, the test injection pulse is commanded during a fuel cut-off phase of the engine. This embodiment has the advantage that the diagnostic method does not affect the standard fuel injection strategy during the normal operation of the engine.
According to still another aspect of the invention, the test quantity of fuel is less than approximately 1 mm 3 . This small injected fuel quantity has the advantage of releasing to the crankshaft a torque that is generally not perceived by the driver.
According to an embodiment, the released torque is determined as a function of a rotational speed variation of the engine crankshaft due to said injection pulse. This embodiment is based on the assumption that there is a strict relationship between the torque released at the crankshaft and the rotational speed of the latter, so that is quite simple to calculate the released torque as a function of the rotational speed variation.
According to another embodiment, the rotational speed of the crankshaft is measured by means of an encoder associated to the crankshaft. As a matter of fact, the modern engines are always provided with an encoder associated to the crankshaft for other managing purposes, so that this solution allows a simple and economical way to monitor the crankshaft rotational speed also while performing the diagnostic method here concerned.
According to another embodiment, the diagnostic method comprises the further step of performing an emergency procedure when the released torque falls outside a torque range which comprises the expected value of said torque. This embodiment advantageously allows the diagnostic method to face up to an excessive drift of the injection timing, when this excessive drift is detected.
According to another embodiment, the emergency procedure provides for generating an alert signal. This aspect provides a simple and economic way to signal the malfunction of the fuel injection system.
The embodiments of the method described above may be carried out with the help of a computer program comprising a program code or computer readable instructions for carrying out all the method steps described above. The computer program can be stored on a data carrier or, in general, a computer readable medium or storage unit, to represent a computer program product. The storage unit may be a CD, DVD, a hard disk, a flash memory or the like. The computer program can be also embodied as an electromagnetic signal, the signal being modulated to carry a sequence of data bits which represent a computer program to carry out all steps of the methods.
The computer program may reside on or in a data carrier, e.g. a flash memory, which is data connected with a control apparatus for an internal combustion engine. The control apparatus has a microprocessor which receives computer readable instructions in form of parts of said computer program and executes them. Executing these instructions amounts to performing the steps of the method as described above, either wholly or in part.
The electronic control unit 60 or, in general, an ECA (Electronic Control Apparatus) can be a dedicated piece of hardware such as an ECU (Electronic Control Unit), which is commercially available and thus known in the art, or can be an apparatus different from such an ECU, e.g., an embedded controller. If the computer program is embodied as an electromagnetic signal as described above, then the electronic control apparatus, e.g. the ECU or ECA, has a receiver for receiving such a signal or is connected to such a receiver placed elsewhere. The signal may be transmitted by a programming robot in a manufacturing plant. The bit sequence carried by the signal is then extracted by a demodulator connected to the storage unit, after which the bit sequence is stored on or in said storage unit of the ECU or ECA.
Another embodiment relates to an apparatus for diagnosing a fault in a fuel injection system of an internal combustion engine. The apparatus comprises means for commanding an injection pulse for injecting a test quantity of fuel into an engine cylinder, means for determining the torque released to an engine crankshaft due to a combustion of said test quantity of fuel, means for calculating the difference between this torque and an expected value for said torque and means for diagnosing a fault if said difference exceeds a threshold value. This apparatus reliably detects whether the fuel injection system is able to provide the desired injection timing.
An embodiment of the apparatus has determination means for carrying out a determination through an empirically determined map correlating the expected value with one or more engine operating parameters, such as for example engine speed, intake air mass flow, injected fuel quantity and other. This embodiment has the advantage that the map can be determined with an experimental activity and then stored in a data carrier, thereby simplifying the diagnosis of the injection system faults.
Another embodiment of said apparatus has means for commanding configured to command during a fuel cut-off phase of the engine. This aspect of the invention has the advantage that the apparatus does not affect the standard fuel injection strategy during the normal operation of the engine. A further embodiment of the apparatus has means for commanding being configured to use a test quantity of fuel being less than 1 mm 3 . This small injected fuel quantity has the advantage of releasing to the crankshaft a torque that is generally not perceived by the driver.
Still another embodiment has determination means being configured to determine the released torque as a function of a rotational speed variation of the engine crankshaft due to said injection pulse. This embodiment of the invention is based on the assumption that there is a strict relationship between the torque released at the crankshaft and the rotational speed of the latter, so that is quite simple to calculate the released torque as a function of the rotational speed variation.
A further embodiment comprises an encoder for measuring the rotational speed of the crankshaft, said encoder being associated with the crankshaft. As a matter of fact, the modern engines are always provided with an encoder associated to the crankshaft for other managing purposes, so that this solution allows a simple and economic way to monitor the crankshaft rotational speed also while performing the diagnostic method here concerned.
Still another embodiment of the apparatus has means for performing an emergency procedure when the released torque falls outside a torque range which comprises the expected value of said torque. This embodiment advantageously allows the apparatus to face up to an excessive drift of the injection timing, when this excessive drift is detected. It is furthermore possible to choose an apparatus wherein said performing means are configured to provide an emergency procedure for generating an alert signal, for example by activating an indicator light on the dashboard of the vehicle.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will hereinafter be described in conjunction with the following drawing figures, wherein like numerals denote like elements, and:
FIG. 1 is a schematic representation of a Diesel engine; and
FIG. 2 is a flowchart representing a diagnostic method according to an embodiment.
DETAILED DESCRIPTION
The following detailed description is merely exemplary in nature and is not intended to limit the application and uses. Furthermore, there is no intention to be bound by any theory presented in the preceding background or summary or the following detailed description.
An embodiment of the invention is hereinafter described with reference to a Diesel engine 10 of a motor vehicle. The Diesel engine 10 schematically comprises a plurality of cylinders 20 , in each of which a piston (not shown) reciprocates due to the fuel combustion, so as to rotate a crankshaft 30 . The fuel is supplied by means of a fuel injection system 40 arranged for injecting fuel directly into the engine cylinders 20 .
The fuel injection system 40 schematically comprises a fuel injector 41 per engine cylinder 20 , and a fuel pump 42 that draws the fuel from a tank 43 and delivers it under pressure into a fuel rail 44 connected to all fuel injectors 41 . Each fuel injector 41 is governed by an Engine Control Unit (ECU) 50 , which opens and closes the fuel injector 41 so as to perform single injections of fuel which are conventionally referred as injection pulses.
In greater detail, during normal operation of the Diesel engine 10 , namely when the accelerator pedal (non shown) is at least partially pushed, the ECU 50 carries out a standard injection strategy that provides for each fuel injector 41 to perform a plurality of injection pulses per engine cycle, according to a determined multi-injection pattern. Each injection pulse is conventionally controlled by the ECU 50 on the base of two key parameters, including the individual quantity of fuel to be injected, and the timing at which said individual quantity of fuel must be injected.
The injection timing is determined by the instant at which the ECU 50 commands the fuel injector 41 to open, also referred as Start Of Injection (SOI), which can be expressed either in temporal term or in term of angular position of the crankshaft 30 . The individual injected fuel quantity is determined by the opening time of the fuel injector 41 , namely the time between the instant at which the ECU 50 commands the fuel injector 41 to open and the instant at which the ECU 50 commands the fuel injector 41 to close, also referred as Energizing Time (ET). Both the SOI and the ET are determined by the ECU 50 taking into account a plurality of engine operating parameters, such as engine speed, engine load, coolant temperature, fuel rail internal pressure and other.
An embodiment provides a diagnostic test for detecting a malfunction of the fuel injection system 40 when the system is unable to deliver fuel at the proper timing. The diagnostic test is performed while the Diesel engine 10 is in a fuel cut-off phase, namely when the accelerator pedal is completely released and the standard injection strategy provides for maintaining the fuel injectors close. In this way, the diagnostic test does not affect the normal operation of the Diesel engine 10 .
Referring now to FIG. 2 , the diagnostic test firstly provides for commanding a fuel injector 41 to perform an injection pulse at a preset SOI, in order to inject a test quantity of fuel into the respective engine cylinder 20 . The test fuel quantity is a small quantity, typically not greater than 1 mm3, in order to have no effect on the torque perceived by the driver of the motor vehicle. The diagnostic test then provides for monitoring the torque TRa actually released to the crankshaft 30 due to the test fuel quantity injected by the injection pulse. The released torque TRa is determined as a function of the variation of the rotational speed of the crankshaft 30 , which is real time measured by means of an encoder 51 associated to the crankshaft 30 itself.
The relationship between the rotational speed variation of the crankshaft 30 and the released torque is well known to the skilled man, so that it is not described in further detail. The released torque TRa is then compared to an expected value TRe for said torque, which represent the torque that should be released to the crankshaft 30 if the injection pulse actually starts at the preset SOI. The expected value TRe can be determined through an empirically determined map correlating the expected value TRe with a plurality of engine operating parameters, such as engine speed, intake air mass flow and other. The expected value TRe is then sent to an adder that calculates the modulus E of the difference between the actual released torque TRa and the expected one TRe.
If the modulus E is equal or smaller than a threshold value E*, it means that the test injection pulse is actually started at the preset SOI, or at least with an allowable drift, and that the fuel injection system 40 works properly. If conversely the modulus E is greater that the threshold value E*, it means that the test injection pulse is actually started with an unallowable drift, and that a malfunction of the fuel injection system 40 is occurred. In the latter case, the diagnostic test provides for generating an alert signal, for example by activating an indicator light on the dashboard of the vehicle.
As a matter of fact, the threshold value E* defines an admissible torque range that is centered on the expected value TRe for the released torque, and that comprises the values of the released torque for which the drift between the preset SOI and the actual start of the injection pulse is allowable. If the actual released torque TRa falls outside of said admissible torque range, a malfunction of the fuel injection system is detected. The threshold value E* can be determined through an empirically determined map correlating the threshold value E* to a plurality of engine operating parameters, such as engine speed, intake air mass flow and other.
Since the injection timing drift is considered unallowable when it causes at least a vehicle's NMHC, CO, NOx or PM emission to exceed an applicable emission level specified by the antipollution regulation, the threshold value E* is calibrated accordingly. Notwithstanding the present embodiment discloses an admissible torque range centered on the expected value TRe, the invention does not exclude that the range could be asymmetrical with respect to the expected value TRe.
According to an embodiment, the diagnostic test can be performed on a fuel injector 41 only, or can be repeated on some or all the fuel injectors 41 . According to an embodiment, the diagnostic test can be performed with the help of a dedicated computer program comprising a program-code for carrying out all the steps of the method described above. The computer program is stored in a data carrier 52 associated to the engine control unit (ECU) 50 , which is in turn connected to the encoder 51 . In this way, when the ECU 50 executes the computer program, all the steps of the method described above are carried out.
While at least one exemplary embodiment has been presented in the foregoing summary or detailed description, it should be appreciated that a vast number of variations exist. It should also be appreciated that the exemplary embodiment or exemplary embodiments are only examples, and are not intended to limit the scope, applicability, or configuration in any way. Rather, the foregoing summary and detailed description will provide those skilled in the art with a convenient road map for implementing an exemplary embodiment, it being understood that various changes may be made in the function and arrangement of elements described in an exemplary embodiment without departing from the scope as set forth in the appended claims and their legal equivalents. | A method is provided to diagnose a fault in a fuel injection system of an internal combustion engine. The method includes, but is not limited to commanding an injection pulse for injecting a test quantity of fuel into an engine cylinder, determining the torque released to an engine crankshaft due to the injection pulse, calculating the difference between this released torque and an expected value for the torque, and of detecting a fault in the fuel injection system if the difference exceeds a threshold. | 5 |
FIELD OF THE INVENTION
The present invention relates generally to movement of fluid, such as a high gas-to-liquid ratio fluid, and particularly to the use of multiple pumps, in which at least one pump pressurizes the fluid and delivers the pressurized fluid to a production pump.
BACKGROUND OF THE INVENTION
Certain types of pumps, such as centrifugal pumps, can lose efficiency or even be damaged when pumping multi-phase fluids having a relatively high gas content. For example, such pumps often are used in the production of subterranean fluids, such as oil, where the fluid can exist in a multi-phase form within the reservoir. In one type of application, a wellbore is drilled into the reservoir of desired fluid, and a pumping system is deployed in the wellbore to raise the desired fluid. The pumping system may comprise an electric submersible pumping system that utilizes a submersible motor to power a production pump, such as a centrifugal pump. When the produced fluid is a multi-phase fluid comprising oil and gas, performance of the pumping system can be substantially limited.
SUMMARY OF THE INVENTION
The present invention relates generally to a technique for moving fluids having a relatively high gas-to-liquid ratio, such as certain fluids produced from subterranean reservoirs. The technique can be utilized with, for example, an electric submersible pumping system used within a wellbore for the production of oil. Of course, the technique may have applications in other environments and with other types of fluid.
In this technique, a compressor pump is employed to compress the vapor phase in a multi-phase fluid. This pressurized fluid is then delivered to a production pump that moves the fluid to a desired location. By delivering fluid to the production pump with reduced or eliminated vapor phase, the efficiency and longevity of various types of production pumps can be improved.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will hereafter be described with reference to the accompanying drawings, wherein like reference numerals denote like elements, and:
FIG. 1 is a front elevational view of an exemplary electric submersible pumping system disposed within a wellbore;
FIG. 2 is a front elevational view of an exemplary electric submersible pumping system utilizing the present technique;
FIG. 3 is a partial cross-sectional view taken generally along the axis of a production pump and a compressor pump, according to one aspect of the present invention;
FIG. 4 is a cross-sectional view of the compressor pump illustrated in FIG. 3 taken generally along the axis of the pump;
FIG. 5 is an enlarged view of a portion of a stage similar to those illustrated in FIG. 4; and
FIG. 6 is a cross-sectional view similar to that of FIG. 4 but showing an alternate embodiment of the pump.
DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS
Referring generally to FIG. 1, an exemplary application of the inventive technique is illustrated. Although this is one embodiment of the invention, a variety of other applications and environments may benefit from the inventive technique disclosed herein. In this embodiment, an electric submersible pumping system 10 is illustrated. Submersible pumping system 10 comprises a variety of components depending on the particular application in which it is used. Typically, system 10 comprises at least a production pump 12 which, in this application, is a centrifugal pump. The system also comprises a submersible motor 14 that powers production pump 12 . Typically, a motor protector 16 is coupled to motor 14 to isolate internal motor fluids from wellbore fluids. Furthermore, submersible pumping system 10 comprises a fluid intake 18 and a vapor phase reduction or compressor pump 20 . (See also FIG. 2)
In the illustrated example, submersible pumping system 10 is designed for deployment in a well 22 within a geological formation 24 containing desirable production fluids, such as petroleum. In this application, a wellbore 26 is drilled and lined with a wellbore casing 28 . Wellbore casing 28 typically has a plurality of openings 30 , e.g. perforations, through which production fluids flow into wellbore 26 .
Submersible pumping system 10 is deployed in wellbore 26 by a deployment system 32 that also may have a variety of forms and configurations. For example, deployment system 32 may comprise tubing 34 connected to electric submersible pumping system by a connector 36 . Power is provided to submersible motor 14 via a power cable 38 . Submersible motor 14 , in turn, powers production pump 12 and compressor pump 20 which draws production fluid in through pump intake 18 and pumps the production fluid to production pump 12 . Production pump 12 then pumps or produces the fluid to a collection location 40 , e.g. at the surface of the earth. In this embodiment, production pump 12 produces fluid through tubing 34 .
It should be noted that the illustrated electric submersible pumping system 10 is an exemplary embodiment. Other components can be added to this system and other deployment systems may implemented. Additionally, the production fluids may be pumped to the surface through tubing 34 or through the annulus formed between deployment system 32 and wellbore casing 28 . These and other modifications, changes or substitutions may be made to the illustrated system.
As illustrated best in FIG. 2, the various components of electric submersible pumping system 10 are coupled together at appropriate mounting ends. For example, production pump 12 typically includes an outer housing 42 having an upper mounting end 44 and a lower mounting end 46 . Similarly, compressor pump 20 comprises an outer housing 48 having an upper mounting end 50 and a lower mounting end 52 . Intake 18 also has an upper mounting end 54 and a lower mounting end 56 ; motor protector 16 has an upper mounting end 58 and a lower mounting end 60 ; and submersible motor 14 has at least an upper mounting end 62 .
The various mounting ends permit each of the components to be selectively coupled to the next adjacent components for assembly of a desired electric submersible pumping system 10 . This modular approach permits individual components to be substituted, removed, repaired and/or rearranged. In the embodiment illustrated, adjacent mounting ends are held together by appropriate fasteners, such as bolts 64 .
The illustrated production pump 12 and compressor pump 20 are separate or independent units that may be selectively and independently coupled into electric submersible pumping system 10 at a variety of locations. In the present embodiment, compressor pump 20 is coupled to production pump 12 at a location upstream from production pump 12 . In this manner, compressor pump 20 receives wellbore fluid through intake 18 and sufficiently compresses the wellbore fluid to remove undesired pockets of vapor phase in the wellbore fluid. The pressurized fluid is discharged directly to production pump 12 , e.g. a centrifugal pump. With the vapor phase removed or substantially reduced, production pump 12 is able to efficiently produce fluid to desired location 40 .
As illustrated in FIG. 3, a desirable compressor pump 20 comprises a helico-axial pump contained within its own separate housing 48 . As described above, housing 48 has an upper mounting end 50 that may be selectively coupled to the next adjacent component which, in this case, is production pump 12 and specifically lower mounting end 46 of production pump 12 . The mounting ends may be standard mounting ends used with components of electric submersible pumping systems. To aid explanation, compressor pump 20 will hereinafter be referred to as helico-axial pump 20 .
Helico-axial pump 20 comprises a central or axial shaft 66 that is rotated or powered by submersible motor 14 . Shaft 66 is rotatably mounted within housing 48 by appropriate bearing structures 68 . Typically, shaft 66 comprises a splined lower end 70 and a splined upper end 72 to facilitate coupling to corresponding shaft segments in adjacent components. Furthermore, shaft 66 typically extends through a plurality of stages 74 . The number of stages will vary according to the level of pressurization desired for a given environment or application. However, the embodiment illustrated in FIG. 3 shows eight stages 74 .
Each stage 74 comprises a helical impeller 76 rotationally affixed to shaft 66 . The helical impeller 76 may be rotationally affixed to shaft 66 in a variety of ways known to those of ordinary skill in the art, such as through the use of a key and keyway (not shown). As illustrated best in FIGS. 4 and 5, each helical impeller 76 comprises a central hub portion 78 and a fin 80 helically wrapped about central hub portion 78 .
Each stage 74 also comprises a diffuser 82 designed to direct fluid discharged from the corresponding helical impeller 76 . An exemplary diffuser 82 is rotationally affixed with respect to housing 48 and comprises a central opening 84 to rotatably receive shaft 66 therethrough. Each diffuser 82 further comprises a flow channel 86 through which fluid is directed upwardly upon discharge from helical fin 80 of the subsequent, lower helical impeller 76 . In this design, a bearing assembly or bearing unit 89 is combined with at least some and often all of the diffusers 82 to promote longevity of the pump.
When shaft 66 and helical impellers 76 are rotated, fluid is drawn through a housing inlet 88 from intake 18 and directed upwardly through each stage until discharged through a housing outlet 90 to production pump 12 . In the embodiment illustrated, shaft 66 is coupled to a shaft 92 of production pump 12 by an appropriate coupling device 94 . Thus, rotation of shaft 66 causes rotation of shaft 92 in production pump 12 . Generally shaft segments 66 and 92 , as well as other shaft segments for additional components, each have a single diameter. It should be noted that the production pump 12 illustrated in FIG. 3 is a centrifugal pump as is commonly used in electric submersible pumping systems for the production of wellbore fluids. However, other types of production pumps also may be utilized in some applications.
The helico-axial pump 20 is designed to generate a lower head than centrifugal pump 12 . Also, the efficiency of the helico-axial pump 20 may be lower than that of the production pump provided it is able to compress the vapor phase in the fluid to a level the centrifugal pump 12 is able to handle without substantial, detrimental head degradation. The use of a helico-axial pump to remove vapor phase is particularly beneficial and, in combination with a centrifugal pump, has resulted in substantially improved production parameters. Additionally, the modular design of the system with separate pump housings and separate shafts connected by coupling device 94 permit ease of assembly, disassembly, servicing, replacement, etc. of either or both pumps.
Furthermore, bearing assemblies 89 promote longevity and reliability of pump 20 . In the embodiment illustrated in FIG. 5, the bearing assemblies 89 are combined with individual diffusers 82 to provide a combined diffuser/bearing unit. The exemplary bearing assembly 89 comprises a radial bearing 96 mounted in a bearing seat or receiving area 98 of diffuser 82 . An annular bushing 100 is mounted to shaft 66 and deployed radially inward from radial bearing 96 . Typically, annular bushing 100 is rotationally affixed to shaft 66 such that a radially outer surface 102 of annular bushing 100 slides against a radially inward surface 104 of radial bearing 96 .
As illustrated, one or more, e.g. two, O-rings 106 may be deployed between radial bearing 96 and bearing receiving area 98 . The O-rings 106 are resilient and allow for a slight amount of movement of radial bearing 96 to accommodate slight variations in shaft 66 . Additionally, a retainer ring 108 may be used to position radial bearing 96 within bearing receiving area 98 . Radial bearings 96 and corresponding annular bushings 100 can be deployed at each stage or selected stages, such as every other stage.
An alternate embodiment of helico-axial pump 20 , labeled 20 ′, is illustrated in FIG. 6 . In this embodiment, a separate bearing unit 110 is disposed between several of the helical impellers 76 and diffusers 82 . For example, the various components may be sequentially arranged from bottom to top in the order: helical impeller 76 , diffuser 82 , bearing unit 110 , helical impeller 76 , diffuser 82 , bearing unit 110 , etc. Each bearing unit 110 has a flow path 112 to permit the flow of fluid therethrough. Bearing units 110 typically are utilized in place of the bearing assemblies 89 discussed above with reference to FIGS. 4 and 5. Bearing units 110 can be designed, for example, to incorporate radial bearings and annular bushings similar to those described above with respect to bearing assemblies 89 .
Because the gaseous phase has a tendency to accumulate in the radial center of the pump, lack of lubrication between bearing and shaft can become a problem in certain environments or applications. Accordingly, bearing structures 68 , radial bearings 96 , annular bushings 100 , and bearing units 110 can be designed with wear-resistant materials for such applications. Exemplary materials comprise ceramic materials, such as zirconia and silicon carbide. In the embodiment illustrated in FIGS. 4 and 5, for example, both the radial bearing 96 and annular bushing 100 can be made from ceramic materials. Use of such materials prolongs the useful life of helico-axial pumps 20 and 20 ′.
It will be understood that the foregoing description is of exemplary embodiments of this invention, and that the invention is not limited to the specific forms shown. For example, the technique may be useful in other applications and environments in which multi-phase fluids are pumped from one location to another; a variety of electric submersible pumping system components may be added, changed or substituted for the components illustrated and described; the number of stages used in either the compressor pump or production pump can be adjusted; and the materials utilized may vary. These and other modifications may be made in the design and arrangement of the elements without departing from the scope of the invention as expressed in the appended claims. | A technique for facilitating the movement of multi-phase fluids. The technique utilizes a compressor pump and a production pump. The compressor pump compresses a fluid to remove vapor phase and then discharges the pressurized fluid to a production pump. The production pump produces the pressurized fluid to a desired location with greater efficiency due to reduction of the vapor phase. | 5 |
BACKGROUND OF THE INVENTION (IMS-1)
There exists a need in motion control applications for the use of step motors as through-hole motors in semiconductor, manufacturing and medical processes that use light emitted by lasers, radar positioning pedestals, and environmentally controlled chambers. Current step motor designs do not easily adapt to such through motor applications without substantial modification.
One example of a motor having an internal opening is found in U.S. Pat. No. 4,646,689 entitled "Engine Intake Passage Length Varying Device" wherein a cylindrical rotor is mounted co-axially with a hollow chamber that contains the air filter of an automotive engine.
U.S. Pat. No. 4,280,072 entitled "Rotating Electric Machine" and U.S. Pat. No. 5,369,324 entitled "Electric Stepper Motor" both describe highly efficient rotor and stator configurations to provide enhanced motor torque.
The state-of-the-art stepper motor designs do not readily allow motors to be stacked end-to-end for multi-axis motion nor allow passage of electric wires or air passage through the center of the motors. Such motors do not readily allow field conversion from a rotary to lineal actuator without substantial modification to the mounting structure.
One purpose of the invention is to describe a stepper motor having means for passage of wires and the like through the center of the motor along with improved motor torque efficiency. The motor includes means for conversion from rotary to lineal actuation with only minor modification to the motor mounting structure.
SUMMARY OF THE INVENTION
An electric stepper motor includes a thru-hole, a rotor and a stator. The stator is internally arranged within the rotor assembly and the rotor assembly consists of a permanent magnet with two rotor cups. The motor can be field-converted from rotary to lineal translation by attachment of a threaded nut to the motor shaft mounting face. The thru-hole allows use with a chamber and provides transport of hardware and elements into the chamber.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a front sectional view of the motor according to the invention depicting the rotor cup teeth and stator teeth;
FIG. 2 is a side sectional view of the motor of FIG. 1 depicting the rotary and stationary components;
FIG. 3 is an exploded front perspective view of the sequentially stacked rotor laminations contained within the motor of FIG. 1;
FIG. 4 is an exploded top perspective view of the magnet within the motor of FIG. 1 with the rotor cups in isometric projection;
FIG. 5A is a front sectional view side view of the rotor shaft assembly within the motor of FIG. 1 in partial section;
FIG. 5B is a side sectional view side view of the rotor shaft assembly of FIG. 5A;
FIG. 6 is a side sectional view the motor of FIG. 2 including a threaded nut attached to the shaft mounting face; and
FIG. 7 is a side sectional view the motor of FIG. 6 excluding a thru-hole in the motor.
DESCRIPTION OF THE PREFERRED EMBODIMENT
As shown in FIGS. 1 and 2, the stepper motor 9 includes a motor assembly 17 consisting of a rotor assembly 41 having outside and inside laminations 10,11, arranged around a rotor cup 12 defining rotor cup outer teeth 13 within the rotor cup-magnet assembly 26. The rotor assembly 41 rotates within the permanent magnet 15 defining a permanent magnet inside diameter 16 arranged between the rotor cup outer teeth 13, the rotor cup magnet assembly 26 and the stator 24. The magnet assembly 26 rotationally operates in the manner similar to that described within U.S. Pat. No. 5,448,117 entitled "Stepper Motor" whereby the rotary components, generally depicted at 44, rotate within the stationary components, generally depicted at 45 as shown in FIG. 2. In accordance with the invention, a thru-hole 40 extends concentrically through the shaft housing 20, between the front shaft mounting face 30 and the end cap mounting post 28 to provide for the transfer of fluids or the passage of electric cables and the like without interfering with the rotation of the rotor assembly 41. The rotary components 44 and stationary components 45 are contained within the motor housing 32 which consist of the front mounting flange 19, front ball bearings 21 and rear ball bearings 22 and the entire motor assembly 17 is assembled together by means of housing screws 33, bolts 43 and grommets 38 as indicated.
The assembly of the rotor cup 12 within the motor 9 is best seen by now referring jointly to FIGS. 3 and 4 wherein the outer motor laminations 10 are in the form of thin outer rotor discs 14 of magnetic metal defining a plurality of outer rotor teeth 13 formed on the inner perimeter thereof. The outer rotor discs 14 are cemented together to form a rotor flange as depicted at 23. The inner motor laminations 11 are in the form of thin inner rotor discs 27 of similar magnetic metal defining a plurality of inner rotor teeth 18 formed on the inner perimeter. The inner rotor discs 27 are cemented together to form a rotor stem 25 that is cemented to the to the rotor flange 23 to complete the rotor cup 12.
A pair of rotor cups 12A, 12B as shown in FIG. 4 are arranged on opposite ends of the cylindrical permanent magnet 15, defining a permanent magnet aperture 16. The stem 25A of the rotor cup 12A is inserted within one end of the permanent magnet aperture 16 such that the underside of the flange 23A abuts against the outer perimeter of the permanent magnet as depicted at 15A. The stem 25B of the rotor cup 12B is inserted within the opposite end of the permanent magnet aperture 16 such that the underside of the flange 23B abuts against the outer perimeter of the permanent magnet as depicted at 15B to complete the rotor cup magnet assembly 26.
The stepper motor subassembly 37 is shown in FIGS. 5A and 5B with the rotor cups 25A, 25B comprising the rotor cup magnet assembly within the inner diameter 16 of the permanent magnet 15 such that a gap 31 is defined between the ends of the stems 25A, 25B extending from the flanges 23A, 23B described earlier. The outer motor laminations 10 are co-planar with the corresponding inner rotor laminations 11 and the corresponding inner rotor teeth 18 align with the corresponding outer rotor teeth 13. The inner rotor teeth and the inner rotor teeth having a predetermined tooth pitch for optimum rotor torque and the gap 31 is set at 1/2 the tooth pitch for motor positional accuracy. The stepper motor subassembly 37 is positioned within the shaft housing 20 with the apertures 43 within the shaft mounting face arranged for completing the stepper motor 9 as now shown in FIG. 6.
The complete stepper motor 9 with the motor assembly 17, rotor assembly 41, permanent magnet 15 contained within the motor housing 32 shown in FIG. 6. The outer and inner ball bearings 21, 22 are positioned at the ends of the motor shaft housing 20 the stator assembly 24 is arranged under the rotor cups 12A, 12B. The step-shaped stationary component 45 extends within the permanent magnet inside diameter 16 at one end and terminates at an end cap mounting post 28 at the opposite end outer rotor laminations 10, and inner rotor laminations 11 within the rotor cup magnet assembly 26 of the rotary component 44 are aligned within the permanent magnet aperture 16. In the embodiment depicted in FIG. 6, a threaded shaft 36 extends through the permanent magnet aperture 16 and is supported on the shaft mounting face 30 by means of the threaded hub 34 including the hub body 35 and threaded apertures 43 that receive the bolts 39. The grommet 38 seals the remainder of the magnet inside diameter 16 from the exterior of the motor assembly 17. As described earlier, the permanent magnet aperture can remain empty of a shaft to allow for the transfer of electric wiring, fluid pipes or circulating fluids.
A further embodiment of a complete motor assembly 9' is shown in FIG. 7 with the similar components indicated as in FIG. 6. In this embodiment, the threaded shaft 36 is eliminated and the end cap 28' of the step-shaped stationary component 45' extends further within the aperture 16 of the permanent magnet 15. The rotor assembly 41' is provided with a front shaft extension as depicted at 41A to provide the motor shaft function. In this arrangement, no motor thru-hole is required.
A stepper motor has herein been described having a two-piece rotor assembly for improved torque efficiency along with an interior thru-hole for field-installation of a shaft, air passage or electric wiring and the like. | An electric stepper motor includes a thru-hole, a rotor and a stator. The rotor consists of a pair of hollow magnetic metal flange-shaped laminations arranged within a hollow magnetic sleeve. The motor can be field-converted from rotary to lineal translation by attachment of a threaded nut to the motor shaft mounting face. The thru-hole allows use with a chamber and provides transport of hardware and elements into the chamber. | 8 |
BACKGROUND OF THE INVENTION
This invention relates to a sensor element for detecting trace amounts of gaseous reducing substances such as alcohols, aldehydes, hydrocarbons, carboxylic acids, amines, and carbon monoxide contained in the atmosphere, exhaust gases, the breath, etc., or for determination of oxygen concentration and a method for detecting the gaseous substances.
For detecting trace amounts of reducing gases contained in these atmospheres, there have been conventionally known such methods as gas chromatography and a method of detection by use of a semi-conductor element. As for the gas chromatography, it cannot be said to be a convenient and inexpensive detecting method because it requires a large-scale apparatus and a certain degree of skill for analytical procedures. Among detecting methods which make use of a semiconductor element as the sensor, there has been known, for example, a method which utilizes the change in specific resistance of a shaped piece comprising n-type stannic oxide as the main constituent, resistance change of which takes place by adsorption of ethanol vapor. This method, however, has such disadvantages that the ethanol vapor once adsorbed on the sensor will not be desorbed unless the sensor is heat-treated at a temperature of 350° C. or higher, and, in addition, the sensor has an extremely large temperature coefficient of resistance, viz. about 5 to 10 %/° C.
On the other hand, for detecting oxygen concentration in the atmosphere, there is known a method in which a galvanic cell is employed. This method, however, has such disadvantages that the response is slow, the life of the element is only about 6 months counting from preparation of the element, and the solution contained in the sensing element will raise a problem of maintenance.
There is known also another method for measuring oxygen concentration by the solid-state oxygen concentration cell method which employs an oxygen ion conductive solid electrolyte such as, for example, (Zr, Ca)O.sub. 2 -y . According to this method, the partial pressure of oxygen in a sample gas is measured by the oxygen concentration cell method using gaseous oxygen, in which the oxygen partial pressure Po 2 is 1.0 atm, or air, in which the oxygen partial pressure is 0.21 atm, as the standard gas for reference. This method, however, has such disadvantages that the sensor will not operate with stability unless the temperature is above about 800° C., and the output voltage is low in case oxygen concentration of the sample gas approximates that of the standard gas.
SUMMARY OF THE INVENTION
This invention relates to a gas-sensor element which may detect rapidly and quantitatively a reducing gas contained in the atmosphere, exhaust gases, or the breath, or an oxygen concentration, and which has stable response performance. More particularly, this invention relates to a gas-sensor element characterized by comprising a complex metal oxide having a perovskite-type crystal structure and represented by the general formula A 1 -x A' x BO 3 - .sub.δ, wherein A is at least one element selected from the group consisting of rare earth elements of the atomic numbers from 57 to 71, yttrium, and hafnium, A' is at least one element selected from the group consisting of alkaline earth metals and lithium, B is at least one element selected from the group consisting of transition metals of the atomic numbers from 21 to 30, O is oxygen, x is in the range of 0 ≦ x ≦ 1, and δ is a nonstoichiometric parameter.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is the isothermal diagram representing the relationship between the composition (x) of the complex metal oxide Nd 1 -x Sr x CoO 3 and the specific resistance.
FIG. 2 is the schematic diagram illustrating the change in the rate of reaction with the change in temperature in the case of catalytic oxidation of ethanol with the perovskite-type complex oxide.
FIG. 3 is a diagram representing the relationship between the equilibrium oxygen partial pressure of the complex oxide Sm 0 .6 Sr 0 .4 CoO 3 and the specific resistance.
FIG. 4 is a diagram representing the relationship between the ethanol concentration and the change of resistance of an element comprising Nd 0 .77 Sr 0 .23 CoO 3 .
FIG. 5 is a diagram representing the relationship between the ethanol concentration and the change of resistance of an element comprising LaNiO 3 .
FIG. 6 is the diagram representing the change in specific resistance of elements comprising Nd 0 .77 Sr 0 .23 CoO 3 and LaNiO 3 , respectively, with the change in temperature.
FIG. 7 is a diagram representing temperature dependency of the change of resistance of an element comprising LaNiO 3 .
FIG. 8 is a diagram representing the response characteristics of n-type tin oxide conventionally used as an ethanol-sensing element.
FIG. 9 is a diagram showing response characteristics of the elements comprising LaNiO 3 .
FIG. 10 is a diagram representing the relationship between the oxygen partial pressure and the specific resistance of an element comprising Sm 0 .4 Sr 0 .6 CoO 3 .
FIG. 11 is the diagram representing the relationship between the resistance of an element comprising La 0 .993 Sr 0 .007 NiO 3 and the temperature.
FIG. 12 is the diagram representing the relationship between the resistance of the same element as in FIG. 11 and the oxygen partial pressure.
FIG. 13 is the diagram representing the relationship between the ethanol concentration and the change of resistance of an element comprising Pr 0 .5 Sr 0 .5 CoO 3 .
FIG. 14 is the diagram representing the relationship between the temperature and the change of resistance or the response rate of the same element as in FIG. 13.
FIG. 15 is a diagram representing the relationship between the temperature and the change of resistance of an element comprising Sm 0 .5 Sr 0 .5 FeO 3 .
FIGS. 16, 17, and 18 are diagramatic representations of the range of x, wherein the perovskite-type crystal structure exists, in the complex oxides A 1 -x Ca x CoO 3 , A 1 -x Sr x CoO 3 , and A 1 -x Ba x CoO 3 , respectively.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
It was already reported that certain complex metal oxides having a perovskite-type crystal structure and represented by the general formula A 1 -x A' x BO 3 - .sub.δ (hereinafter referred to simply as complex oxide and the number of oxygen atoms in the formula is expressed as 3, δ being omitted from the expression unless specially needed) show a favorable electric conductivity. The present inventors have now found that the specific resistance of the complex oxide is correlated with the concentration of a reducing gas or the concentration of oxygen in an atmosphere, under which the complex oxide is placed, and thus accomplished the present invention.
For synthesizing the above-said complex oxide, there are available various methods. For instance, in synthesizing from oxides, predetermined amounts of the component oxides are weighed out, ground finely, and mixed thoroughly. A sample is obtained by sintering the oxide mixture at between 1,000° to 1,400° C. for 2 to 24 hours. During the sintering, the oxygen partial pressure is controlled in the following manner. According to the magnitude of the tolerance factor for perovskite structure, either a reducing or an oxidizing atmosphere is used. An oxygen partial pressure in the range of 10 - 20 to 1 atmosphere is suitably selected. If the selection of atmosphere is improper, the result is not a perovskite structure but an oxide or an oxide mixture of different structure. After sintering the sample is quenched, if necessary, in liquid nitrogen or in ice water at 0° C.
In synthesizing from carbonates, nitrates, oxalates, or acetates, predetermined amounts of these salts are weighed out and treated at 500° to 1,200° C. in a manner similar to that in the case of oxides. When there is a large difference between the decomposition temperatures of the salts and the temperature of formation of the perovskite structure, decomposition should be brought to completion by supplying air or oxygen during the decomposition. As compared with the method in which oxides are used as the starting material, the present method is characterized by capable of synthesizing the perovskite-type oxide at a lower temperature. The method has further advantages over the oxide in that since the components can be mixed by wet process, it is possible to obtain more uniform and more finely powdered complex oxide.
A method which makes use of an alkali metal carbonate as a flux is useful when it is desired to obtain a perovskite-type oxide which cannot be obtained by either of the above two methods. As the flux, it is preferred to use carbonates of alkali metals such as lithium, potassium, and sodium, or mixtures of these carbonates. For example, single-phase LaNiO 3 cannot be obtained even under a controlled atmosphere. On the contrary, when a predetermined amount of a mixture of oxide components or a mixture of decomposition products of salts is thoroughly mixed with sodium carbonate in a ratio of 1 : 1 by weight and kept at a temperature above the melting point of sodium carbonate, i.e. 851° C., for example, at 900° C. for 3 hours, the product contains LaNiO 3 as the main constituent. The said product is kept at the said temperature for 10 hours or more and then freed from the carbonate to obtain single-phase LaNiO 3 .
On the other hand, the complex oxide having a perovskite-type crystal structure is not always obtained throughout the entire range of composition covered by the aforesaid general formula. For instance, when cobalt is selected as the element B in the general formula, calcium, strontium, or barium as the element A', and various rare earth elements as the element A, the range of x wherein a perovskite-type crystal structure is formed is as shown in FIGS. 16, 17, and 18. These Figures, however, represent the cases where acetates used as starting materials are mixed and sintered in air at 1,000° C. for 7 hours. If the sintering is conducted under an atmosphere which has been controlled for the oxygen partial pressure as mentioned before, the range of x wherein a perovskite-type crystal structure is formed can be made broader.
FIG. 16 relates to A 1 -x Ca x CoO 3 , FIG. 17 to A 1 -x Sr x CoO 3 , and FIG. 18 to A 1 -x Ba x CoO 3 , respectively. The region hatched with solid oblique lines and marked with O represents region of the perovskite-type crystal structure, the region hatched with dotted oblique lines and marked with Δ represents the region where the perovskite-type crystal structure is mixed with other oxide phases to form two or more phases, and the region marked with x represents the region where no perovskite structure is formed.
Strontium is desirable to be used as the element A', because a perovskite-type crystal structure is formed over a broad range of x.
The above-said complex oxides are used in the form of shaped piece or film as a sensing element.
When it is intended to obtain a sensor element in the form of plate, rod, or disc, the complex oxide is shaped into any desired form and then sintered at 800° to 1,100° C. for 0.5 to several hours. When it is intended to obtain a coating in the form of film on an alumina plate, a silica glass, or other suitable base-plates, the complex oxide is mixed with a PVA (polyvinyl alcohol) solution, or a methylcellulose solution to form a slurry which is coated on a base plate, and then sintered in a manner similar to that mentioned above, to form a sensing element. Further, the complex oxide can be supported on a porous carrier or mixed with an inert powder, and then sintered. The porosity of the element thus prepared is generally in the range of 60 to 70 %. It is needless to say that in any case the element show better performance characteristics when used in the form having greater specific surface area.
It was already mentioned in the foregoing that quite different from an ordinary oxide, the perovskite-type complex oxide has an extremely high electric conductivity even at room temperature. In FIG. 1 is shown, as an example, the results of measurement of specific resistance conducted on a specimen, about 35 mm long, about 10 mm wide, and about 3 mm thick, prepared by sintering a complex oxide of the formula Nd 1 -x Sr x CoO 3 . In the Figure, the curves 1, 2, and 3 are plots of the data obtained in air at 25°, 300°, and 700° C., respectively. As is clear from the Figure, it is seen that the specific resistance decreases with the increase in x. As is seen also from this example, it has been known that the specific resistance decreases as the number of oxide components increases from binary oxide to ternary and more multiplicated system. Thus, those complex oxides are preferable for use which are of the general formula in which x is within the range 0 < x < 1.
The data on specific resistance mentioned hereinafter were obtained from the measurement conducted on the test specimen having nearly the same form as that mentioned above.
It is also known that in a perovskite-type oxide represented by the formula A 1 -x A' x BO 3 - .sub.δ, the nonstoichiometric parameter δ varies easily according to the oxygen partial pressure during formation of the oxide and to the subsequent heat history of the oxide. Consequently, the specific resistance also varies to some exent according to said conditions.
On the other hand, when air containing minute amounts of a reducing gas, such as, for example, the air containing about 0.2 mg/liter of ethanol is allowed to contact with the aforesaid element while being heated at 100° to 500° C., oxygen ions are liberated from the complex metal compound to oxidize ethanol, and the specific resistance of the shaped piece increases with the liberation of oxygen ions. The variation rate of resistance amounts to the order of several ten percent for an ethanol concentration of about 0.2 mg/liter, a concentration usually found, for example, in the breath of an individual who took an alcoholic beverage. The response of the resistance change is also rapid. The temperature coefficient of resistance of the perovskite-type oxide is, in most of the cases, about 0.2 %/° C. or smaller at room temperature to 800° C., and the signal-to-noise ratio (S/N ratio) is also so favorable as may be left out of consideration in practical applications. Further, another important feature of the present material is recovery of resistance to the initial resistance due to re-entry of oxygen from air into the perovskite crystal when the material is left in the air after contacting with ethanol. Thus, the material may be utilized as an ethanol sensor with favorable stability and reproducibility.
Although the foregoing explanation is given by reference to ethanol as an example, circumstances are the same with other reducing gases.
The catalytic action of the above-said complex oxide is explained below with reference to ethanol as an example. The oxidation of ethanol seems to take place by the following reactions:
C.sub.2 H.sub.5 OH + 6 Cat(0*)→ 2 CO.sub.2 + 3H.sub.2 O + 6 Cat. (V) (1)+ 6 Cat. (V) + 3 O.sub.2 → 6 Cat. (0*) (2) C.sub.2 H.sub.5 OH + 3 O.sub.2 → 2 CO.sub.2 + 3 H.sub.2 O (3)
where
Cat. O * ): oxygen in the complex oxide crystal,
Cat. (V): oxygen vacancy in the complex oxide crystal.
If the rates of reactions (1) and (2) are denoted by k 1 and k 2 , respectively, then the following equations should hold:
k.sub.1 = A.sub.1.sup.. exp (-ΔE.sub.1 /k.sub. B τ ) (4)
k.sub.2 = A.sub.2.sup.. exp (-ΔE.sub.2 /k.sub. B τ) (5)
where
A 1 , A 2 : constant
ΔE 1 , Δ E 2 : activation energy of the reaction
k B : Boltzmann's constant
τ: Absolute temperature
The relation between the activation energy of reaction, ΔE 1 and ΔE 2 , is estimated as
ΔE.sub.1 < Δ E.sub.2 (6)
the relation between τ - 1 and log k is shown schematically in FIG. 2. The straight lines 21 and 22 show the temperature dependency of the rate of reactions (1) and (2), respectively. The dotted straight line 23 show the lower limit above which the reactions substantially takes place.
With special regard to the variation in oxygen content of a sensor element comprising the complex oxide during oxidation of ethanol, the following scheme may be presumed. Under the given conditions of the temperature τ and the oxygen partial pressure Po 2 at the temperature τ, the complex oxide assumes a δ value (δ o ) so that the composition may be
A.sub.1.sub.-x A'.sub.x BO.sub.3.sub.-.sub.δ.sbsb.0 where δ.sub.o is δ.sub.o (τ, Po.sub.2 ) (7)
corresponding to the existing equilibrium. When ethanol is supplied, the complex oxide acts as a catalyst and the composition shifts according to the following formula:
A.sub.1.sub.-x A'.sub.x BO.sub.3.sub.-.sub.δ.sbsb.0 ⃡ A.sub.1.sub.-x A'.sub.x BO.sub.3.sub.-(.sub.δ.sbsb.0 .sub.+ .sub.δ.sub.') + (δ'/2)O.sub.2 (8)
as compared with the composition in the absence of ethanol, the composition of the complex oxide catalyst assumes a greater δ value, i.e. δ o + δ', which is determined by the ratio between each rate of the reactions (1) and (2). The temperature of the sensor element seems also to be increased to some degree due to enthalpy of the oxidation reaction of ethanol.
In FIG. 3 is shown the change in specific resistance with the change in oxygen partial pressure in the atmosphere with respect to Sm 0 .6 Sr 0 .4 CoO 3 - .sub.δ. As is clear from FIG. 3, it is seen that in a complex oxide the decrease in oxygen partial pressure in the atmosphere results in the increase in specific resistance.
As is shown by the formula (8), the complex oxide assumes a larger δ value in the presence of ethanol than in the absence thereof and it is clear from FIG. 3 that the difference in δ results in the change in resistance of the test specimen. Thus, these phenomena clearly suggest that the complex oxides be useful as the sensing elements for reducing gases, of which ethanol is a representative.
Now, as mentioned before, the straight lines 21 and 22 in FIG. 2 represent temperature dependency of rate of reactions according to the equations (4) and (5), respectively, which correspond to the reactions (1) and (2), respectively. In the Figure, the temperature range can be divided into three zones according to the relative magnitude of reaction rates k 1 and k 2 in the following manner:
k.sub.1 > k.sub.2 . . . τ < τ.sub.1
k.sub.1 = k.sub.2 . . . τ = τ.sub.1
k.sub.1 < k.sub.2 . . . τ > τ.sub.1 (9)
where τ 1 is the temperature at which k 1 becomes equal to k 2 . At τ = τ 1 , equilibrium is attained when δ becomes (δ o + δ 1 ), a value shifted from δ o by δ 1 , said δ o being the δ value in the equilibrium composition in the absence of ethanol. Similarly, δ in the equilibrium compositions in other temperature zones are as follows:
τ < τ.sub.1 δ > δ.sub.o (τ.sub.1, P.sub.o.sbsb.2) + δ.sub.1 (τ, C.sub.E.sub.+OH)
τ = τ.sub.1 δ = δ.sub.o (τ.sub.1, P.sub.o.sbsb.2) ) δ.sub.1 (τ, C.sub.E.sub.+OH)
τ > τ.sub.1 δ < δ.sub.o (τ.sub.1, P.sub.o.sbsb.2) + δ.sub.1 (τ, C.sub.E.sub.+OH) (10)
where δ o (τ, P o .sbsb.2) and δ 1 (τ, C E +OH ) represent that δ o and δ 1 are functions of temperature and oxygen partial pressure or ethanol concentration. From these formulas it is anticipated that in the presence of an alcohol the nonstoichiometric parameter δ becomes larger with the decrease in temperature, and accordingly, the change in specific resistance also becomes larger with the decrease in temperature. On the other hand, the dotted straight line 23 in FIG. 2 represents the lower limit of the practically significant rate of reaction. It is understandable that with the decrease in temperature the rate of reaction diminishes rapidly until the reactions (1) and (2) no longer practically take place, and accordingly, relative amount of the effectiveness of the catalyst also decreases, accompanied by the decrease in change of the nonstoichiometric parameter δ. It seems that as the overall result of the above-said two competitive tendencies, the maximum change in specific resistance occurs at a certain temperature. This suggests that there exists an optimum range of operating temperatures for the sensor.
The invention is illustrated below in further detail with reference to Examples.
Example 1
A complex oxide, Nd O .77 Sr 0 .23 CoO 3 , was mixed with a PVA solution to form a slurry and the slurry was coated on an alumina base-plate to cover an area measuring 2 mm wide by 7 mm long. Then, the coated oxide was sintered to obtain an element.
In FIG. 4 is shown the relationship between the ethanol concentration and the change of resistance of the element placed under an atmosphere containing ethanol. The data were obtained at 390° C. The resistance of the element was 0.16 Ω. It is seen that there exists a sufficiently linear relation between the change of resistance and the ethanol concentration within the range of concentration (0 to 2 mg/liter) usually found in the breath of an individual who has taken an alcoholic beverage. As will be appreciated by those skilled in the art, changes in resistance are measured by apparatus. This apparatus will be referred to in the specification and claims as means for measuring the change in resistance of the material being referred to.
EXAMPLE 2
An element similar to that in Example 1 was prepared by use of LaNiO 3 . In FIG. 5 is shown the behavior of the element in detecting ethanol at 250° C. From the Figure it is seen that similarly to the case in Example 1, the relationship between the concentration and the variation rate of resistance of the element is also sufficiently linear. By comparison of FIG. 4 with FIG. 5, it may be said that Nd 0 .77 Sr 0 .23 CoO 3 shows a smaller change of resistance than LaNiO 3 . Generally speaking, nickel often shows a large change. However, as shown in FIG. 6, Nd 0 .77 Sr 0 .23 CoO 3 (curve 61 in FIG. 6) is characterized to be of smaller temperature coefficient of resistance than that of LaNiO 3 (curve 62 in FIG. 6), and may be effectively employed in the case where a sensing element of small temperature coefficient of resistance is required.
In FIG. 7 is shown temperature dependency of the change of resistance of the element in the presence of 0.8 mg/liter of ethanol. As fully discussed hereinbefore, on examination of the catalytic reaction of an alcohol resolved into two steps, a suggestion is offered for the possible existence of an optimum temperature for the change of resistance. It is seen in FIG. 7 that the present element has such an optimum temperature at 250° C. or thereabout.
COMPARATIVE EXAMPLE 1
In FIG. 8 are shown the results obtained by using n-type tin oxide (SnO 2 ) which has been known as an ethanol-sensing element. In the Figure, t d represents a dead time and t r a response time. Supply of ethanol was started at the point 4 and discontinued at the point 5. The temperature was 170° C. As is seen from the Figure, with the supply of ethanol the resistance decreases to a figure down about one place. However, the trouble in this case is that as is seen from the Figure, the initial resistance is not restored even in the absence of ethanol. Therefore, the element is entirely unsuitable for the continual-repetitive at a constant temperature.
In Table 1 are shown t d and t r observed for tin oxide at various temperatures.
Table 1______________________________________Reactiontempera- Initialture td tr resistance Final resistance(°C.) (sec.) (sec.) (k Ω) (Ω)______________________________________144 50 180 4.2 300200 5 20 16 120260 5 15 12 <1,000 1,300 (Returns to the340 5 15 110 initial value in 4 min.)______________________________________
From the table, it is seen that restoration of initial resistance is resulted when the element is heated at a temperature of about 350° C. or higher. This indicates that in the case of an element comprising a semiconductor such as n-type tin oxide, although the change in its resistance is large due to adsorption of ethanol, restoration of the initial resistance is not possible unless the adsorbate is desorbed because said element lacks catalytic activity for oxidation. Consequently, the element is unsuitable for continued use at lower temperatures, as is the case with the sensing element comprising perovskite-type oxide according to this invention. It was also observed that when used at a temperature above 350° C., the element comprising tin oxide deteriorates severely.
EXAMPLE 3
In a manner similar to that in Example 1, an element was prepared by use of LaNiO 3 . In Table 2 are shown sensing performance of the element for various gases at 250° C. In the Table, the mark (+) and (-) show occurrence and absence, respectively, of the change in resistance. The number of (+) shows relative magnitude of the change in resistance.
Table 2______________________________________Sample gas Response of sensor______________________________________Acetone +++Ethanol +++Methanol +++Petroleum benzine ++Toluene +Benzene +Ether +++Water -Hydrogen peroxide -Trichloroethylene ++Ammonia -Carbon monoxide +++______________________________________
EXAMPLES 4 to 29
Elements similar to that in EXAMPLE 1 were prepared by using various complex oxides. The sensing performance of these elements for ethanol 250° C. are shown in Table 3.
Table 3______________________________________ Specific Gas sensingExample resistance perform-No. Complex oxide (Ω-cm) ance______________________________________4 YCrO.sub.3 ˜10.sup.2 +5 YFeO.sub.3 ˜10 +++6 Hf.sub.0.1 La.sub.0.8 Sr.sub.0.1 CoO.sub.3 7 × 10.sup.-.sup.3 ++7 La.sub.0.8 Sr.sub.0.2 Co.sub.0.9 Ni.sub.0.1 O.sub.3 6 × 10.sup.-.sup.4 ++8 La.sub.0.8 Sr.sub.0.2 Co.sub.0.8 Ni.sub.0.1 O.sub.3 1 × 10.sup.-.sup.3 ++9 Nd.sub.0.9 Sr.sub.0.05 Ba.sub.0.05 CoO.sub.3 4 × 10.sup.-.sup.2 ++10 Nd.sub.0.8 Sr.sub.0.1 Ba.sub.0.1 CoO.sub.3 2.6 × 10.sup.-.sup.3 +++11 La.sub.0.1 Sr.sub.0.9 MnO.sub.3 ˜10.sup.2 +12 La.sub.0.2 Sr.sub.0.8 FeO.sub.3 ˜10.sup.-.sup.1 ++++13 Pr.sub.0.75 Sr.sub.0.25 MnO.sub.3 ˜10.sup.-.sup.1 ++14 Pr.sub.0.25 Sr.sub.0.75 FeO.sub.3 ˜10.sup.0 ++++15 Pr.sub.0.8 Sr.sub.0.2 CoO.sub.3 5 × 10.sup.-.sup.4 +++16 Pr.sub.0.5 Sr.sub.0.5 CoO.sub.3 3.8 × 10.sup.-.sup.4 ++++17 Sm.sub.0.5 Sr.sub.0.5 FeO.sub.3 2.4 × 10.sup.-.sup.2 ++++18 Sm.sub.0.2 Sr.sub.0.8 CoO.sub.3 3.4 × 10.sup.-.sup.4 +++19 Y.sub.0.25 Sr.sub.0.75 MnO.sub.3 ˜10.sup.1 ++20 SrCo.sub.0.5 Fe.sub.0.5 O.sub.3 ˜10.sup.0 ++++21 Sm.sub.o.5 Sr.sub.0.5 Co.sub.0.8 Fe.sub.0.2 O.sub.3 1.8 × 10.sup.-.sup.3 ++++22 La.sub.0.995 Sr.sub.0.005 Ni.sub.0.8 5 × 10.sup.-.sup.3 ++++ Fe.sub.0.2 O.sub.323 CaMnO.sub.3 2 × 10.sup.2 ++24 Nd.sub.0.5 Sr.sub.0.5 CoO.sub.3 2.1 × 10.sup.-.sup.4 +++25 Gd.sub.0.5 Sr.sub.0.5 CoO.sub.3 1.4 × 10.sup.-.sup.4 ++++26 Dy.sub.0.5 Sr.sub.0.5 CoO.sub.3 3 × 10.sup.- .sup.2 ++++27 Er.sub.0.5 Sr.sub.0.5 CoO.sub.3 8 × 10.sup.-.sup.1 +++28 Yb.sub.0.5 Sr.sub.0.5 CoO.sub.3 4 × 10.sup.0 +++29 Pr.sub.0.769 Sr.sub.0.231 MnO.sub.3 ˜10.sup.1 ++______________________________________
EXAMPLE 30
By using elements in various forms, which comprised LaNiO 3 , behavior of each element in detecting ethanol was tested to obtain the results as shown in FIG. 9. The curve 91 represents the behavior of a cylindrical element, 5.75 mm in diameter and 6.95 mm in height; the curve 92 that of a cylindrical element, 3.00 mm in diameter and 4.0 mm in height; and the curve 93 that of an element in the form of rectangular film, 2.00 mm in width and 7.00 mm in length, coated on an alumina base-plate. In the Figure, supply of ethanol was started at the point 4 and discontinued at the point 5. The temperature of measurement was 250° C. From FIG. 9 it is seen that a favorable response is obtained from the element in the form which provides a large surface of contact with a gas so that the reaction may take place rapidly.
EXAMPLE 31
An element similar to that in Example 1 was prepared by use of Sm 0 .4 Sr 0 .6 CoO 3 . In FIG. 10 is shown the change in specific reistance of the element at 500° C. with the change in oxygen partial pressure. It is seen that the specific resistance of the complex oxide changes in accordance with the change in oxygen partial pressure and that there is a difference amounting to about 20 % between the specific resistance in the air and that in an atmosphere containing 1% oxygen.
EXAMPLE 32
In FIG. 11 are shown temperature dependencies of the resistance of a sensing element comprising La 0 .993 Sr 0 .007 NiO 3 under atmospheres containing oxygen in various concentrations. The element used was prepared by coating the complex oxide on an alumina base-plate to a thickness of about 5μ to cover an area of 3 mm width by 12 mm length, an then sintered. In FIG. 11, the curves 111, 112 and 113 show the resistance of the element in oxygen (P o .sbsb.2 = 1.0 atm), air (P o .sbsb.2 = 0.21 atm), and a gas mixture of 1 % O 2 --N 2 (P o .sbsb.2 = 0.01 atm), respectively.
When the element B in the general formula is cobalt, a particularly favorable sensitivity is shown by a composition in which x (a factor relating to the proportion of A' which replaced a part of A) is large, whereas when the element B is nickel, a favorable sensitivity is shown regardless of whether x is large or small or even zero. This is presumably because Ni 2 + is stable as well as Ni + 3 in the complex oxide.
In FIG. 12 is shown the change in resistance of the element with the change in oxygen partial pressure. The curves, which were plotted on the basis of data shown in FIG. 11, represent dependency of the resistance on oxygen partial pressure. The curves 121, 122, and 123 represent the said dependency at 250°, 450°, and 600° C., respectively. At 250° C. and 600° C. resistance of the element increases in proportion to oxygen partial pressure. At 450° C. the curve representing dependency of the resistance on the oxygen partial pressure is somewhat convexed downward.
The rate of response of this element increases with the rise in temperature.
In Table 4 is shown, as an example, the rate of response of the element when atmosphere is changed from air (corresponding to the point 124 in FIG. 12) to an atmosphere of 1 % oxygen (corresponding to the point 125 in FIG. 12).
Table 4______________________________________ Rate of response (min.)Temperature Time constant(°C.) (0 to 1-1/e res- ponse time)______________________________________250 > 25450 3.8600 1.5800 0.2______________________________________
The rate of response is improved rapidly with the rise in temperature.
EXAMPLE 33
An element similar to that in Example 1 was prepared by using Pr 0 .5 Sr 0 .4 CoO 3 . In FIG. 13 is shown the change of resistance of the element relative to the ethanol concentration. The curves 131, 132, and 133 correspond to the temperatures of the element of 325°, 372°, and 417° C., respectively. In FIG. 14 are shown the change of resistance and the response rate under an atmosphere containing 150 ppm ethanol. The curves 141, 142, and 143 represent ascent response rate, descent response rate, and change of resistance, respectively. The change of resistance reaches the maximum at about 280° C. and decreases at higher temperatures. The response rate is expressed in terms of percentage of the change in resistance based on the saturation level, which change took place in a period of one minute after contact with ethanol or after termination of contact with ethanol. It is seen that the response rate rapidly changes in the range of 200° to 300° C., and that an optimum temperature range for the element to operate is from about 320° to 330° C. in consideration of the change of resistance and the response rate. The change of resistance relative to the ethanol concentration at a temperature within the said range is shown by the curve 131 of FIG. 13. It is apparent that the complex oxide shows a most favorable response rate as well as a large change of resistance even at higher ethanol concentrations. In comparison with the element in Example 1, it is seen that complex oxides containing cobalt differ from each other in response performance depending upon the kind of rare earth element and the strontium content.
EXAMPLES 34 to 36
Elements similar to that in Example 1 were prepared by using Pr O .25 Sr 0 .75 FeO 3 , La 0 .2 Sr 0 .8 FeO 3 , and Sm 0 .5 Sr 0 .5 FeO 3 , respectively. The change of resistance of these elements against 150 ppm ethanol were as shown in Table 5, Table 6, and FIG. 15, respectively.
Table 5______________________________________(Pr.sub.0.25 Sr.sub.0.75 FeO.sub.3)Temperature(°C.) Change of resistance (%)______________________________________212 62273 134334 226367 250398 340451 150503 32______________________________________
Table 6______________________________________(La.sub.0.2 Sr.sub.0.8 FeO.sub.3)Temperature(°C.) Change of resistance (%)______________________________________221 35287 168370 180431 163______________________________________
A change of resistance of 1,300 % at 310° C. shown in FIG. 15 is one of the highest change in this invention. In this case it was found that with the rise in temperature the change of resistance decreases, whereas the response rate increases.
The above three Examples show that when iron is used as the element B in the general formula, the resulting complex oxide shows a high change of resistance ranging from several hundred to a thousand percent or higher to 150 ppm ethanol. It is to be noted that in these examples selection of the elements A and A' beside B and the amount of doping with A' also greatly affect the change of resistance. While these examples demonstrated the effectiveness of employing iron as the element B, favorable results may also be obtained by joint use of two or more metals such as iron-cobalt, iron-nickel, or iron-nickel-cobalt. In general, incorporation of cobalt in the complex oxide often results in reduced electric resistance, improved reproducibility, and also easier synthesis of the complex oxide.
As stated in the foregoing, the gas-sensor element of this invention is distinguished in sensing performance for an oxidizable gas. Examples of most suitable applications of the element include a sensor for detecting oxidizable gases in the exhaust gas from factorys and shops, an automatic on-off control device for a ventilating fan by means of detecting carbon monoxide in living-environments, a fire and smoke alarm by means of detecting carbon monoxide and smoke, and a sensor for estimating concentration of ethanol in the breath of an individual who has taken an alcoholic beverage.
The gas-sensor element of this invention is also distinguished in determination of the oxygen concentration and is widely applicable to automatic ventilation of air-conditioned dwelling houses and shops by detecting oxygen content of the indoor air, a detection and alarm system for the oxygen-deficient air in mines and building spots, a ventilation system for use in a tunnel by detecting air pollution, a system for detecting air pollution in living-environments under waters, a detection and alarm system for atmospheric pollution in a closed environment, etc. | A gas-sensor element for detecting reducing gases and vapors such as alcohols or carbon monoxide, or for determining oxygen concentration, which is characterized by comprising a complex metal oxide having a perovskite-type crystal structure and represented by the general formula A 1 -x A' x BO 3 - .sub.δ, wherein A is at least one element selected from the group consisting of rare earth elements of the atomic numbers from 57 to 71, yttrium, and hafnium, A' is at least one element selected from the group consisting of alkaline earth metals and lithium, B is at least one element selected from the group consisting of transition metals of the atomic numbers from 21 to 30, O is oxygen, x is in the range of 0 ≦ x ≦ 1, and δ is a nonstoichiometric parameter. | 8 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to data mining and, more particularly, to a method of visually detecting relationships between values of related goals and variables of a plurality of design points of a circuit.
[0003] 2. Description of Related Art
[0004] Heretofore, methods of generating analog circuit designs were based on synthesis programs implemented on a computer. Each synthesis program generates a set of design points for a circuit based upon design variables, design goals and constraints for the circuits. More specifically, each design point is determined from a common set of variables and a common set of goals for the circuit, with each design point having at least one variable or goal different from each other design point.
[0005] Each design point also has a cost or cost value associated therewith. The cost of each design point represents the quality of the design point with respect to a given set of goals, each having a target value and a constraint associated therewith. Design points where the goals better satisfy their design constraints have a lower cost associated therewith.
[0006] Depending on the type of circuit design and the user specified set of information that is input into the synthesis program, the number of design variables and goals vary from several hundred to several thousand. After a synthesis run is complete, a single combination of design variable values and design goal values, i.e., a single design point, is selected. This design point is used as a starting point for an implementation of the circuit on a semiconductor chip. In another application, a set of design points is generated by sampling in the vicinity of a chosen design point. This is typical when the existing “best” design needs to be improved or when it is desired to better understand local variations in the design variables and the design goals.
[0007] Given the large size of the set of design points and the number of variables and goals, it is difficult for a human designer to understand the advantages or disadvantages of selecting a particular design point. It is also difficult to focus on a desired subset of design points by using conventional inspection techniques, such as examining the numerical/textual output of the synthesis program or examining design points one by one. Even when using advanced database querying techniques, significant challenges remain in analyzing this large data set with the large number of design variables and design goals.
[0008] Accordingly, it is desirable to overcome the above problems and others by providing a visual data mining technique that enables analysis of the generated set of design points to provide an easy and fast understanding of important properties of the generated designs; fast, intuitive and easy selection of subsets of design points, or a single design point, with desired properties based on the analysis; and which significantly reduces the time for analysis of the design space and the decision on which design point to choose for practical implementation.
SUMMARY OF THE INVENTION
[0009] The invention is a method of selecting one of a plurality of circuit design points to utilize for implementing a circuit. The method includes providing a database having a plurality of design points for a circuit, with each design point determined as a function of a set of goals for the circuit and a set of variables for the circuit. Each design point has a value of at least one goal or one variable that is different from each other design point. A cost is determined for each design point as a function of the set goals for the circuit and, more particularly, as a function of the values of the set of goals for the design point. A cost versus design point chart is displayed having indicia at the intersection of each cost-design point pair. A plurality of indicia is selected in the cost versus design point chart. At least one of the following is displayed: (1) at least one goal variable chart that includes an indicia for the value of the goal and the value of the variable of each design point associated with the selected indicia in the cost versus design point chart; (2) a parallel goal coordinates chart having a plurality of spaced parallel axes each associated with one of the set of goals, with the range of values of each axis related to the range of values of the corresponding goal of the design points associated with the selected indicia in the cost versus design point chart, where the parallel goal coordinates chart includes for each design point associated with the selected indicia in the cost versus design point chart a line that extends through the parallel goal coordinates chart and intersects each axis at the value of a corresponding goal for the design point; and (3) a radar chart having at least three radially extending axes, with each axis representing one of the set of goals, where the radar chart includes a line for each design point associated with the selected indicia in the cost versus design point chart, with each design point line intersecting each axis of the radar chart at the value of the corresponding goal for the design point. One or more of the foregoing charts are utilized to determine which design point to utilize to implement the circuit.
[0010] The method can also include determining at least one of a sensitivity and a correlation for each goal-variable pair associated with each design point associated with the selected indicia in the cost versus design point chart. First and second goal-variable pairs are selected based on the sensitivity or the correlation therefor. First and second goal-variable charts are displayed that includes for each design point of the corresponding first and second goal-variable pairs an indicia related thereto. One of the indicia in the first goal variable chart is selected whereupon a first goal-variable pair of one of the design points is selected. Responsive to the selection of the indicia in the first goal-variable chart, the indicia corresponding to the same design point is highlighted in the second goal-variable chart.
[0011] A constraint can be associated with at least one goal of a design point. Each design point can be classified as feasible where each constraint of the design point is satisfied. Each design point can be classified as infeasible where at least one constraint of the design point is not satisfied.
[0012] The method can also include selecting one goal-variable pair of the set of goals and the set of variables associated with at least the design points associated with a selected indicia. For each design point associated with this selected indicia, the value of the goal and the value of the variable of the selected goal-variable pair can be determined. Variables of a best fit curve equation that represent a best fit line for the thus determined goal and variable values of each design point can be determined. The sensitivity of the selected goal-variable pair can be determined as the function of the best fit line. Also or alternatively, the correlation of the selected goal-variable pair can be determined as a function of the distribution of the goal and variable values of the one goal-variable pair for each design point about the best fit line.
[0013] The invention is also a computer readable medium having stored thereon instructions which, when executed by a processor, cause the processor to display a cost versus design point graph that includes an indicia at the intersection of each cost-design point pair for a circuit. Each design point is determined as a function of a common set of variables and a common set of goals for the circuit where a value of at least one variable or goal of each design point is different from the values of the variables in goals for each other design point. Each cost is determined as a function of the values of the goals for the corresponding design point. A selection of a plurality of indicia in the cost versus design point graph is received and at least one chart is displayed having one of an indicia and a line for each design point associated with the selected indicia in the cost versus design point chart. The at least one chart includes axes for (1) one goal-variable pair; (2) plural goals of the set of goals; or (3) one cost-goal pair. The at least one displayed chart enables selection of one of the design points to utilize for implementing the circuit.
[0014] The instructions can also cause the processor to display a goal versus variable matrix for the design points associated with the selected indicia. The goal versus variable matrix includes in each cell thereof at least one of a sensitivity value and a correlation value for the corresponding goal-variable pair. A selection of first and second goal-variable pairs can be received in the goal-variable matrix. In response to receiving this selection, first and second goal-variable chart can be displayed, with each goal-variable chart including for the goal-variable pair represented thereby an indicia at the intersection of the value of the goal and the value of the variable of each design point associated with the selected indicia in the cost versus design point chart. A selection of one of the indicia in the first goal-variable chart can be received whereupon one of the design points is selected. In response to receiving this selection, the indicia in the second goal-variable chart where the value of the goal and the value of the variable for the same design point is highlighted.
[0015] The instructions can also cause the processor to receive a selection of at least one goal-variable pair of the set of goals and the set of variables associated with the design points associated with the indicia selected in the cost versus design point chart. For the selected goal-variable pair, the value of the goal and the value of the variable for each design point associated with the indicia selected in the cost versus design point chart can be identified. Variables of a best fit curve equation that represent a best fit line for the thus identified goal and variable values of each design point associated with the indicia selected in the cost versus design point chart can be determined for the selected goal-variable pair. The sensitivity of the selected goal-variable pair can then be determined as a function of the best fit line. Also or alternatively, the correlation of the selected goal-variable pair can be determined as a function of the distribution about the best fit line of the goal and variable values of the one goal-variable pair of each design point associated with indicia selected in the cost versus design point graph.
[0016] The chart of plural goals of the set of goals can include a coordinate axis for each of at least three goals of the circuit, with the coordinate axes having a predetermined relation to each other. The graph can also include for each design point associated with the indicia selected in the cost versus design point graph a line that intersects each coordinate axis at a value that corresponds to the value of the corresponding goal for the design point. The graph of plural goals of the set of goals can include a parallel goal coordinates chart having the axes positioned in spaced parallel relation or a radar chart having the axes extending radially from a common center.
[0017] Lastly, the invention is a method of selecting one of a plurality of circuit design points to utilize for implementing a circuit. The method includes providing a database having a plurality of design point for a circuit. Each design point is determined as a function of a common set of goals for the circuit and a common set of variables for the circuit. Each design point has a value of at least one goal or one variable different than each other design point. A set of design points is selected and one of the goals is selected. The values of the selected design points for the selected goal are grouped into at least two groups as a function of the proximity of the values to each other. One of the groups of values is selected whereupon their design points are selected.
[0018] The values of the selected group of values can be grouped into at least two groups as a function of the proximity of the values to each other. Thereafter, the selection of one of the groups of values and the subsequent grouping of the thus selected groups are repeated a desired number of times.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] [0019]FIG. 1 is a chart of design points, variables, goals and costs with associated values in each cell thereof;
[0020] [0020]FIG. 2 is a chart of constraints and target values for the goals of FIG. 1;
[0021] [0021]FIG. 3 is a cost versus design point chart for the costs and design points shown in FIG. 1;
[0022] [0022]FIG. 4 is a sensitivity matrix for each goal-variable pair in FIG. 1;
[0023] [0023]FIG. 5 is a portion of the sensitivity matrix of FIG. 4 and goal-variable charts displayed in response to selecting cells in the sensitivity matrix;
[0024] [0024]FIG. 6 shows a portion of a correlation matrix and a first set of goal-variable charts displayed in response to selecting cells in the correlation matrix;
[0025] [0025]FIG. 7 shows a portion of the correlation matrix and a second set of goal-variable charts displayed in response to selecting cells in the correlation matrix;
[0026] [0026]FIG. 8 is a parallel goal coordinates chart that displays relationships between goals of design points in FIG. 1;
[0027] [0027]FIG. 9 is a goal versus goal chart displayed in response to selecting two goal axes in FIG. 8;
[0028] [0028]FIG. 10 is a cost versus goal chart displayed in response to selecting one goal axis in FIG. 8;
[0029] [0029]FIG. 11 is a radar chart that displays the relationships between three goals and design points shown in FIG. 1; and
[0030] [0030]FIG. 12 shows grouping of goals of selected design points into plural groups as a function of the proximity of the value of the goal for each design point with respect to each other.
DETAILED DESCRIPTION OF THE INVENTION
[0031] The present invention will be described with reference to the accompanying figures where like reference numbers correspond to like elements.
[0032] The present invention is embodied in a computer software computer program which can be configured to run on a general propose computer or work station of the type known in the art. Generally, the present invention utilizes graphical techniques to visually display data regarding a plurality of design points for a circuit generated by a synthesis program implemented on a computer.
[0033] With reference to FIG. 1, the synthesis program utilizes a common set of variables V 1 , V 2 , V 3 , etc., and a common set of goals G 1 , G 2 , G 3 , etc., for determining design points D 1 , D 2 , D 3 , etc., for a circuit. More specifically, for each design point D, an appropriate value is associated with each variable V and each goal G wherefrom the synthesis program determines the performance characteristics of the circuit for these variables V and goals G. The combination of the values of the variables V and the goals G along with the corresponding performance characteristics of the circuit represent the design point for the values of the variables V and the goals G. Stated differently, each design point is a function of the values of the variables V and the goals G utilized to determine said design point.
[0034] Each design point also has a cost C1, C2, C3, etc., associated therewith. A general form algorithm for determining the cost of each design point is shown in the following equation (EQ1). However, it is to be appreciated that other suitable algorithms can be utilized to determine the cost of each design point.
Cost = ∑ i = 1 n f ( G i ) ( w i )
[0035] where i=design point number;
[0036] n=total number of design points;
[0037] G i are goals related to the cost;
[0038] w i are weights used to weigh the contribution of each goal; and
[0039] f(G i ) is an objective function that is utilized to determine the extent to which the corresponding goal is satisfied.
[0040] With reference to FIG. 2, and with continuing reference to FIG. 1, each goal G has associated therewith a design constraint that places a restriction or requirement on a target value for the goal. In FIG. 2, the column “Target Value” includes comparison values and the column “Constraint” contains comparison operators. The comparison operator “minimize” (or “maximize”) means that the value of the corresponding goal should be minimized (or “maximized”) and the target value for that goal is given only as a suggestion to the synthesis program. Constraints can have one of the following operators: minimize, maximize, less than and greater than.
[0041] With reference to FIG. 3, and with continuing reference to FIG. 1, a plurality of design points generated by the synthesis program are stored in a design database. At an appropriate time, a designer can launch a cost versus design point chart 2 that includes indicia 4 at the intersection of each cost and its design point. Indicia 4 having a first appearance or color, e.g., red, represents infeasible design points while indicia 4 having a second appearance or color, e.g., green, represents feasible design points. A feasible design point is one where the constraints associated with the goals of the design point can be met. In contrast, an infeasible design point is one where at least one constraint of one goal cannot be met.
[0042] Next, utilizing appropriate techniques, a designer selects a region 6 of design points to explore. Once region 6 is selected, the designer can perform a sensitivity analysis, a correlation analysis, a goal trade-off analysis, a corners analysis and/or a cluster analysis. The use of all or part of these analyses and the order in which they are utilized are not fixed.
[0043] If, as a result of one or more of the foregoing analyses, the “best” design point is found, the design process is finished. Otherwise, the designer can make adjustments to the values of the variables and/or the goals based upon observations about the current design space, and the synthesis program can be run again with these adjustments. This other synthesis run can be initiated from the beginning of the design evaluation process, or may generate design points in addition to the existing design points. This process is repeated until the “best” design point is found.
[0044] Cost versus design point chart 2 includes a sensitivity button 8 , a correlation button 10 , a goal trade-off button 12 , a comers button 14 and a cluster button 16 which the designer can select in any order to display a corresponding chart, graph or matrix that can be utilized by the designer for elevating design points. The response of the computer software to the activation of each of these buttons 8 to 16 will now be described.
[0045] With reference to FIG. 4, and with continuing reference to FIGS. 1 and 3, in response to selecting sensitivity button 8 , a sensitivity matrix 20 is displayed. Sensitivity matrix 20 includes a matrix of sensitivity cells 22 for the values of the goal G and variable V for each goal-variable pair utilized to determine each design point D in FIG. 1. Each sensitivity cell 22 includes a value that represents a sensitivity of the corresponding goal G to the corresponding variable V, or vice versa. Sensitivity matrix 20 can also include an “Average” column 24 having average cells 26 therein where the value included in each average cell 26 is the average of the values of the goals G for the corresponding variable V. For example, the value 0.01 included in the cell at the intersection of Variable V 1 and “Average” column 24 is the average of the values included in sensitivity cells 22 for each goal G associated with Variable V 1 .
[0046] The sensitivity value included in each sensitivity cell 22 , i.e., each cell at the intersection of a variable V and a goal G, can be determined utilizing the following equation (EQ2) or any other suitable equation:
EQ 2 : S = S xy / S xx where S xy = ∑ i = 1 n x i y i - ( Σ x i ) ( Σ y i ) / n ; S xx = ∑ i = 1 n x i 2 - ( Σ x i ) 2 / n ;
[0047] S=sensitivity;
[0048] i=design point number;
[0049] n=total number of design points;
[0050] x i =variable value of design point i; and
[0051] y i =goal value of design point i.
[0052] The sensitivity value for each goal-variable pair is determined utilizing equation EQ2 for the goal and variable values for each design point D shown in FIG. 1. For example, for the goal-variable pair G 1 -V 1 , the value of goal G 1 and variable V 1 values for each design point D are utilized in equation EQ2 to determine the sensitivity for goal variable pair G 1 -V 1 .
[0053] The value included in each sensitivity cell 22 represents the extent to which the goal changes when the variable changes its value for a unit interval. The value of sensitivity S for each goal-variable pair is a number between ±1.0. A high sensitivity value, i.e., one that is closer to +1 or −1, means that the value of the goal changes significantly for small changes in the value of the variable. In contrast, a low sensitivity value, i.e., one closer to 0, means that changes of the value of the goal are small or negligible for changes in the value of the variable.
[0054] Each cell 22 , 26 can be color coded depending on its sensitivity value such that when the absolute sensitivity value is close to ±1.0, the cell color is brighter. This color coding enables easy identification of entries with higher sensitivity values in the matrix.
[0055] Utilizing suitable techniques, each row or column can be individually selected to display sensitivity values in increasing or decreasing order. For example, the designer can sort on average sensitivity values to obtain variables V that have the strongest average impact on all goals G. Moreover, utilizing appropriate techniques, columns of sensitivity matrix 20 can be moved freely so that goals G in which the designer is most interested can be brought close together and their sensitivities analyzed.
[0056] With reference to FIG. 5, and with continuing reference to FIGS. 1 and 4, utilizing appropriate techniques, one or more sensitivity cells 22 can be selected. For each sensitivity cell 22 selected, a corresponding goal-variable chart is displayed. For example, in response to selecting the sensitivity cell 22 at the intersection of goal-variable pair G 23 -V 18 in FIG. 5, a goal-variable chart 30 is displayed. Similarly, in response to selecting the sensitivity cell 22 at the intersection of goal-variable pair G 22 -V 19 , a goal-variable chart 32 is displayed. Similarly, selecting any other sensitivity cell 22 causes a corresponding goal-variable chart to be displayed.
[0057] Each goal-variable chart 30 and 32 includes a plurality of indicia 34 , each of which represents a design point D in FIG. 1. More specifically, the indicia 34 for each design point D is located in each goal-variable chart 30 and 32 at the intersection of the value for the goal and the value of the variable for the design point D in the chart. For example, suppose that indicia 34 - 1 in goal-variable chart 30 relates design to point D 1 . The position of indicia 34 - 1 in goal-variable chart 30 is based upon the value of goal G 23 and the value of variable V 18 for design point D 1 . Similar comments apply in respect of all other indicia 34 in goal-variable charts 30 and 32 .
[0058] The slopes of imaginary lines 36 and 38 formed by indicia 34 in goal-variable charts 30 and 32 , respectively, are higher for higher sensitivity values and lower for lower sensitivity values. A positive sloping line 36 or 38 indicates a direct relationship between the goal-variable pair and a negative sloping line 30 or 32 indicates an inverse relationship between the goal-variable pair. By evaluating goal-variable charts 30 and 32 , a designer can access the sensitivity of each goal-variable pair that has been selected in the sensitivity matrix.
[0059] With reference to FIGS. 6 and 7, and with continuing reference to FIGS. 3 and 1, in response to the selection of correlation button 10 in cost versus design point chart 2 , a correlation matrix 40 is displayed. Correlation matrix 40 includes a correlation cell 42 for each goal-variable pair of the goals G and variables V utilized to determine each design point D in FIG. 1. Correlation matrix 40 also includes an “Average” column 44 in which the average cells 46 are arranged. Each average cell 46 includes a value that is the average of the correlation values of the goals G for the corresponding variables V. The correlation for each selected goal-variable pair can be determined utilizing the following equation (EQ3) or any other suitable equation:
EQ 3 : r = S xy / ( S xx S yy ) 1 / 2 where S xy = ∑ i = 1 n x i y i - ( Σ x i ) ( Σ y i ) / n ;
S xx = ∑ i = 1 n x i 2 - ( Σ x i ) 2 / n ;
S yy = ∑ i = 1 n y i 2 - ( Σ y i ) 2 / n ; □
[0060] r=correlation;
[0061] i=design point number;
[0062] n=total number of design points;
[0063] x i =variable value of design point i; and
[0064] y i =goal value of design point i.
[0065] The correlation value for each goal-variable pair is determined utilizing equation EQ3 for the goal and variable values for each design point D shown in FIG. 1. For example, for the goal-variable pair G 2 -V 2 , the goal G 2 and variable V 2 values for each design point D are utilized in equation EQ3 to determine the correlation r for the goal-variable pair G 2 -V 2 .
[0066] As shown in FIG. 6, in response to selecting correlation cell 42 at the intersection of a goal-variable pair, a corresponding goal-variable chart having indicia related to each design point is displayed. For example, in response to selecting correlation cells 42 at the intersections of goal-variable pairs G 2 -V 2 and G 3 -V 1 , goal-variable charts 48 and 50 are displayed having indicia 52 corresponding to each design point D in FIG. 1. For example, suppose that indicia 52 - 1 in goal-variable chart 48 corresponds to design point D 1 . In this case, the location of indicia 52 - 1 in goal-variable chart 48 is based on value of variable V 2 for design point D 1 and the value of goal G 2 for design point D 1 . Similar comments apply in respect of the position of the other indicia 52 in each goal-variable chart 48 and 50 . In FIG. 6, groups of indicia 52 are shown aligned in columns. This can occur when the values of variables V 2 and V 1 have discrete values. However, this is not to be construed as limiting the invention since the values of variables V 1 or V 2 can vary continuously whereupon indicia 52 in charts 48 or 50 can be arranged in a scatterplot arrangement like indicia 34 shown in FIG. 5.
[0067] As can be seen, sensitivity matrix 20 and correlation matrix 40 are organized in the same manner. The only difference is that the values displayed in correlation matrix 40 represent correlation values for each goal-variable pair, and their range is between 0.0 and 1.0, with 0.0 representing a low correlation and with 1.0 representing a high correlation value. Each correlation value indicates the degree of linearity between the value of the goal and the value of the variable for the corresponding goal-variable pair.
[0068] A designer can evaluate goal-variable charts 48 and 50 to determine the linearity of the relationship between the corresponding goal-variable pair. This information aids the designer in selecting a suitable design point for implementation.
[0069] Since both similarity and correlation information are relevant, sensitivity matrix 20 and/or goal-variable charts 30 and 32 can alternatingly be displayed with correlation matrix 40 and/or goal-variable charts 48 and 50 in a manner known in the art. Alternatively, correlation values and sensitivity values can be displayed together in the same cell of a combination sensitivity/correlation matrix (not shown). Selecting one of the cells of this sensitivity/correlation matrix can cause a goal-variable chart for sensitivity values and/or a goal-variable chart for correlations to be displayed for use by the designer.
[0070] With reference to FIG. 7, utilizing goal-variable charts of the type shown in FIGS. 5 or 6 , a designer can utilize the present invention to gain an understanding about goal and variable changes when a different design point is selected. For example, the designer can select a plurality of correlation cells 42 for goals of a single variable. For example, the designer can select goals G 1 , G 2 , G 3 and G 4 for variable V 1 . In response to selecting these correlation cells 42 , goal-variable charts 60 , 62 , 64 and 66 are displayed. Similar comments apply in respect of the selection of a plurality of sensitivity cells 22 for goals of a single variable.
[0071] Corresponding indicia in charts 60 to 66 can be linked. Hence, in response to selection of an indicia 68 - 1 in chart 60 , indicia 68 - 2 , 68 - 3 and 68 - 4 for the same design point are highlighted in charts 62 to 66 . Similar comments apply in respect of selecting indicia 34 ; 52 ; or 68 in any of charts 30 and 32 ; 48 and 50 ; and 60 to 66 and highlighting indicia for the corresponding design point in one of the other charts 30 and 32 ; 48 and 50 ; and 60 to 66 , respectively. The size of each indicia 34 , 52 and 68 can be related to the cost of the design point represented thereby. For example, the size of the indicia can be inversely proportional to the cost. Each chart 30 , 32 , 48 , 50 and 60 to 66 can include an indicator 72 that points in the direction of feasible goal values. The indicator 72 in each chart can be color coded so that a first color represents a strict constraint (greater than or less than) and a second color represents a preferential constraint (maximize or minimize).
[0072] The designer can also highlight in one of charts 60 to 66 an indicia 70 that represents an end point for the analysis whereupon corresponding indicia for the same design point are highlighted in the other charts. The highlighting of indicia 70 in each chart 60 to 66 can be utilized to avoid the designer from analyzing undesirable design points.
[0073] By observing changes in goal and variable values in this way for several design points, the designer can gain an understanding of changes in the design space and select a design point that best satisfies the design specification. From the example shown in FIG. 7, it can be seen that the same change in a variable value can cause very different changes in different goal values. Also, the change in goal values does not always follow a general relationship, e.g., linear relationship, suggested by observing all points in charts 60 to 66 .
[0074] With reference to FIG. 8, and with continuing reference to FIG. 3, in response to selecting goal-trade off button 12 , a parallel goal coordinates chart displays multiple goal values on parallel axes. Each line 82 in chart 80 represents a single design point. Each line 80 is color coded to indicate the cost associated therewith. The key to the color code is given in a color bar 84 . The range of cost values displayed on chart 80 can be selected by moving a cost range slider 86 adjacent color bar 84 upwardly or downwardly until the desired range of cost values is displayed. A slider 88 enables adjustment of which goals are displayed in chart 80 . Desirably, all goals are displayed. The range of each goal axis in FIG. 8 is determined from the data currently displayed. Hence, each goal axis can have a different data range.
[0075] Utilizing parallel goal coordinates chart 80 , a designer can observe general trends in data with respect to their cost and goal values. Lines 82 having a first color, e.g., green, (indicated by a solid line) indicate lower cost. By following each line 82 having the first color, a designer can observe changes of individual goals for more acceptable design points. Similarly, by following each line having a second or a third color, e.g., yellow (indicated by a dash-dot-dash line) or red (indicated by a dash-dot-dot-dash line), the designer can observe goal trends and changes for less desirable design points.
[0076] The designer can also observe relationships between adjacent goals in the chart and determine whether direct or inverse relationships between goals exist by observing whether lines 82 are parallel (direct relationship) or crossed (inverse relationship). Each goal axis in parallel goal coordinates chart 80 can be dragged to an arbitrary position within the chart utilizing suitable techniques. This facilitates comparison of any two goals even if the goal axes were not initially adjacent.
[0077] As discussed above, moving cost-range slider 86 upwardly or downwardly applies visual filtering to the data displayed in parallel goal coordinates chart 80 . For example, moving slider 90 upwardly toward slider 92 decreases the range of costs displayed in chart 80 by increasing the value of the lowest cost displayed. Conversely, moving slider 92 toward slider 90 decreases the range of costs displayed on chart 80 by decreasing the value of the greatest cost displayed. Still further, sliders 90 and 92 can be moved toward each other so that the range of cost displayed on chart 80 decreases as a result of decreasing the greatest cost displayed in response to moving slider 92 downward and by increasing the least cost displayed in response to moving slider 90 upward.
[0078] Using cost-range slider 86 , the number of design points displayed on chart 80 can be reduced significantly thereby making analysis of individual lines 82 (design points) easier. To this end, utilizing suitable techniques, a single line can be selected whereupon the goal closest adjacent the point where the line was selected and the cost for the selected design point can be displayed (not shown).
[0079] With reference to FIG. 9, and with continuing reference to FIGS. 3 and 8, the present invention is configured so that selecting two different goals in parallel goal coordinates chart 80 displays a goal versus goal chart 100 . While goal versus goal chart 100 shows goal G 1 versus G 2 , this is not to be construed as limiting the invention since the two selected goals do not need to be adjacent. Goal versus goal chart 100 includes indicia 102 for each design point D of FIG. 1. More specifically, each indicia 102 is positioned at the intersection of the value of goal G 1 and the value of goal G 2 for the corresponding design point D. Goal versus goal chart 100 can also include goal target lines 104 and 106 located on chart 100 at the target value for the corresponding goal. For example, as shown in FIG. 2, goal G 1 has a target value of 0.1. Hence, in FIG. 9, target line 104 intersects the goal G 1 axis at a value of 0.1. Similarly, in FIG. 2, goal G 2 has a target value of 0.02. Hence, in FIG. 9, target line 106 intersects the goal G 2 axis at a value of 0.02.
[0080] Each target line 104 and 106 can also be color coded in accordance with the type of constraint on the corresponding target value. For example, if a target line represents a strict constraint, such as greater than or less than, the line can be a first color, e.g., blue, whereas if a constraint is a preferential constraint, such as minimize or maximize, the line can be a second color, e.g., red.
[0081] The intersection of each target line 104 and 106 with its axis can include a suitable indicator 110 and 112 , respectively, which can point toward goals having feasible values. The size of each indicia 102 can be a function of the cost associated with the corresponding design point. For example, indicia 102 having a large size can indicate a low cost and vice versa. The color of each indicia 102 can also indicate whether the corresponding design point is feasible or infeasible.
[0082] Utilizing goal versus goal chart 100 , the designer can observe a feasibility region 108 for the two selected goals. To this end, if one of the two selected goals is the most important, then selection of a suitable indicia 102 in feasibility region 108 can be made. However, if other goals need to be considered, the designer can analyze relationships for those goals for different goal versus goal pairs in a manner shown in FIG. 9. Moreover, in a manner similar to a plurality of charts 60 to 66 in FIG. 7, a plurality of goal versus goal charts of the type shown in FIG. 9 can be concurrently displayed with indicia for each design point in each chart linked to indicia for the corresponding design point in the other charts. In this manner, the designer can analyze how changes in one pair of goals influence changes in another pair of goals.
[0083] With reference to FIG. 10, and with continuing reference to FIG. 8, in response to selecting a single axis of parallel goal coordinates chart 80 twice in succession, a cost versus goal chart 120 is displayed. For example, if the goal G 1 axis in FIG. 8 is selected twice in succession, cost versus goal chart 120 is displayed.
[0084] Cost versus goal chart 120 includes indicia 122 positioned at the intersection of the value of the cost and the value of the goal for each design point D in FIG. 1. Indicia 122 representing feasible design points can have a first, e.g., green, color while indicia 122 representing infeasible design points have a second, e.g., red, color. The size of each indicia 122 in chart 120 can be the same or feasible design points can have a different size than infeasible design points. As can be seen in cost versus goal chart 120 , the cost value C decreases as the value of goal G 1 increases. The same effect can also be observed in FIG. 9 if the size of each indicia 102 is related to the cost associated with the corresponding design point.
[0085] Other goals can also influence the cost function in an opposite direction from goal G 1 . To gain additional insight into influences of other goals to the cost function, the designer can use multiple cost versus goal charts with linked views and select different indicia on different charts to observe changes across different coordinates in a manner similar to that discussed above in connection with charts 60 to 66 in FIG. 7. Alternatively, the designer can return to visual filtering by cost utilizing cost range slider 84 of parallel goal coordinates chart 80 .
[0086] With reference to FIG. 11, and with continuing reference to FIG. 3, in response to selecting corners button 14 , a goal selection menu 130 and a display button 132 are displayed. In response to selecting three goals, e.g., goal G 1 , G 2 , and G 3 , in goal selection menu 130 and thereafter activating display button 132 , a radar chart 134 is displayed where each goal is represented by an axis that extends radially from a common center. It is desirable in radar chart 134 that each axis extends in a different direction to facilitate discrimination among lines 136 representing design points D in FIG. 1. In the example shown in FIG. 11, the three axes are spaced 120° relative to each other. However, this is not to be construed as limiting the invention since the number of goals selected in goal selection menu 130 will determine the number of axes and their angular spacing with respect to each other around the common center.
[0087] Each line 136 can be color coded based on its cost. For example, a first color, e.g., green, can be utilized to indicate a more favorable cost, a second color, e.g., red, can be utilized to indicate a less favorable cost and a third color, e.g., yellow, can be utilized to indicate an intermediate cost.
[0088] A color bar 140 and a cost-range slider 142 can be provided and used in the manner described above for color bar 84 and cost range slider 86 in FIG. 8 for filtering cost and goals based on color.
[0089] Because of imperfect manufacturing processes and real world environmental conditions, a designer typically validates a design across several different corners. For example, if a design is expected to work at temperatures between 0° C. and 100° C., the designer will simulate the design at least at the two extremes or corners, 0° C. and 100° C. Hence, in radar chart 134 , one goal axis will be for 0° C. and another goal axis will be for 100° C. The third axis can then be another goal such, as the minimum operating voltage.
[0090] Axes of radar chart 134 can also be specified using more than one manufacturing or environmental condition. For example, if a circuit must work between 0° C. and 100° C. and between 2 volts and 2.5 volts, radar chart 134 will have four corners, namely, 0° C. at 2 volts; 0° C. at 2.5 volts; 100° at 2 volts; and 100° C. at 2.5 volts.
[0091] Because of the exponential growth in the number of corners when considering different manufacturing and environmental conditions, typically, between one and ten corners are chosen. These corners are representative corners. However, this number of corners is not to be construed as limiting the invention. Once the goal meets these corners, there is a good chance that the goal will meet all corners. Once an initial design process is complete, the design may be further validated across all or a larger set of corners to ensure that the circuit works correctly.
[0092] It has been observed that it is often difficult to meet a goal value for a particular corner. This can occur for several reasons. One reason may be that the design is overly sensitive at a particular corner. Another may be that redesigning the circuit to meet a goal at one corner can hurt the performance in another corner thus causing a design, redesign, “ping pong” effect that wastes time. Radar charts of the type shown in FIG. 11 can help provide design insight into how a goal is changing from one corner to the next. Specifically, a designer focusing on one corner of radar chart 134 can observe the relationship in the other corners of the radar chart. This enables the designer to observe, among other things, whether the goal at a particular corner is overly sensitive or if there is an inverse relationship between two corners. An inverse relationship implies that there are two competing comers. This could signify a “ping pong” condition. Another important observation that can be made from radar chart 134 is the relative values for a goal at each corner. This enables assessment of how much a goal value changes when moving from one corner to another.
[0093] With reference to FIG. 12, and with continuing reference to FIG. 3, in response to selecting cluster button 16 , a goal selection menu 150 is displayed. Goal selection menu 150 is configured so that only one goal at a time can be selected. Once a goal in goal selection menu 150 has been selected, the values of the selected goal for all of the design points D are clustered into two or more groups 154 as a function of their values and these groups 154 are displayed. For example, as shown in FIG. 12, in response to selecting goal G 5 in goal selection menu 150 , the values of goal G 5 for ten different design points are grouped together, as shown, into Groups I, II and III. However, the number of groups can be changed if desired. The number of groups can be determined automatically or manually. In the example shown in FIG. 12, values of the selected goal are grouped into three separate groups or clusters. The labels “Group I”, “Group II” and “Group III” are assigned to each cluster according to the values of the goal.
[0094] At this point, selection can be made of which group best suits the requirements of the circuit design. For example, for operational amplifiers, it is common to choose a high gain group because the goal is to have gain as high as possible. Hence, if goal G 5 in FIG. 12 is the gain goal, Group III is selected. This selection reduces the number of design points for further exploration.
[0095] Next, the same or another goal can be selected in goal selection menu 150 . If the same goal, i.e., goal G 5 , is selected, the values of the selected goal for all of the design points D associated with selected group 154 are clustered into two or more groups (not shown) as a function of their values and these groups are displayed. However, if a different goal, e.g., goal G 7 , is selected, the values of the selected goal for all of the design points D associated with selected group 154 are clustered into two or more groups 156 as a function of the values of goal G 7 for these design points D and these groups 156 are displayed. The sequential selection of the same or different goals in goal selection menu 150 forms the clustering tree 158 shown in FIG. 12. The process of selecting one of the displayed groups at each level of incremental clustering tree 158 continues until a desired number of design points D have been isolated.
[0096] Concurrent with the selection of each new goal in goal selection menu 150 , a parallel goal coordinates chart, of the type shown in FIG. 8, which includes for each goal selected in goal selection menu 150 a parallel axis and a line for each design point D of the selected group in the lowest level of incremental clustering tree 158 , can be displayed.
[0097] A serialize button 160 can be selected for saving the search strategy displayed in incremental clustering tree 158 to a file for subsequent retrieval and analysis.
[0098] As an alternative to producing incremental clustering tree 158 in the above described manner, a simple script file (not shown) can be prepared that includes the order of importance of analyzed goals and the desired range of values for each goal. In response to activating cluster button 16 in FIG. 3, the script file can be executed to produce an incremental clustering tree, like incremental clustering tree 158 , but without having to incrementally select goals in the manner described above.
[0099] The present invention has been described with reference to the preferred embodiment. Obvious 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 insofar as they come within the scope of the appended claims or the equivalents thereof. | A visualization and data mining technique can be utilized to facilitate analysis of generated sets of design points for an integrated circuit to enable easy and fast understanding of important properties of generated designs. The use of the visualization and data mining technique significantly reduces the time needed for analysis of design space and decision on which design point to choose for implementing into a circuit design. | 6 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention generally relates to a wire connecting device for an electric connection terminal assembly, and more particularly to a wire connecting device comprising a connecting body adapted to connect or disconnect a leading wire easily without any special tools.
2. Description of the Prior Art
Generally, an electric connection terminal assembly is used to distribute electrical signals or electrical energies from the outside or other different equipment to several points. Especially, the electrical connection terminal assembly allows the same amount of energy or the same signal to be transmitted as a strand of the wire is connected to a specific position.
In the past, there is used a wire connecting device that was attained by the steps of drilling several holes at regular intervals on one side of the baseplates connected one another, putting screws having the corresponding diameter into the holes, winding one peeled end of the leading wire around the screws, and tightening the screws.
With such a conventional wire connecting device, it is very troublesome and takes plenty of time to carry out the operation consisting of the steps of peeling one end of the leading wire, winding the peeled end of the wire around the fixing screw, and tightening the screws, as mentioned above.
Lately, there has been developed a wire connecting device adapted to carry out connection of the leading wire more easily, which is disclosed in Korean Utility Model application No. 54481/1996 filed previously in the name of the applicant.
According to the above mentioned wire connecting device, a connecting plate is mounted elastically for connecting leading wires, and a push button is provided for pressing the connecting plate. The method for connecting the leading wire comprises the steps of pulling apart the connecting wire plate by pressing the push button, inserting the peeled end of the connecting wire therebetween, and releasing the push button whereby the leading wire is connected to the connecting plate by virtue of the repulsive force of the spring.
However, such a wire connecting device has a drawback in that the connection terminal assembly is mounted on the control board by weld, thus limiting installation conditions.
On the contrary, in a case that the wire connecting device is to be mounted inside equipment using an angle iron in compliance with the equipment used, it is necessary to provide a structure including the wire connecting device and a securing member adapted to engage into the angle iron.
To this end, a separate wire connecting device is manufactured and used. Therefore, it is required to manufacture at least two types of the device, one being mounted directly on the control board by weld, and the other having the securing member for mounting on the angle iron. In the case of the wire connecting device mounted on the angle iron, it is essential to manufacture various kinds of the assembly including the wire connecting device and the securing member in compliance with the sizes and specifications of equipment from several manufacturers, resulting in higher manufacturing costs.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a wire connecting device for an electric connection terminal assembly eliminating the above mentioned drawbacks.
According to the present invention, this object is accomplished by providing a wire connecting device for an electric connection terminal assembly comprising at least one connecting body adapted to connect or disconnect a leading wire, and at least one exchangeable securing member connected to the bottom of the connecting body, said securing member being formed in various sizes and shapes to connect to the connecting body.
According to one aspect of the present invention, the connecting body has a T-shaped groove formed at its lower part, a T-shaped protrusion is provided on the top of the securing member attached to the connecting body, and on the lower part of the securing member is provided a structure adapted to be fixed to an angle iron.
According to another aspect of the present invention, the connecting body has a T-shaped groove formed at its lower part, a connecting groove at its upper part, a connecting bar inserted into the connecting groove, and a connecting bar arranged on the underside of the connecting strip.
BRIEF DESCRIPTION OF THE DRAWINGS
The details of the present invention will be described in connection with the accompanying drawings, in which:
FIG. 1 is an exploded perspective view showing an embodiment of the wire connecting device with exchangeable securing member for electric connection terminal assembly according to the present invention;
FIG. 2 is an exploded perspective view showing another embodiment of the wire connecting device with exchangeable securing member for electric connection terminal assembly according to the present invention;
FIG. 3 is an exploded perspective view showing the wire connecting device of the present invention;
FIG. 4 is a front view showing the operation of the wire connecting device of the present invention;
FIG. 5 is a side view showing an embodiment of the wire connecting device with exchangeable securing member for electric connection terminal assembly according to the present invention;
FIG. 6 is a side view showing another embodiment of the wire connecting device with exchangeable securing member for electric connection terminal assembly according to the present invention;
FIG. 7 is a front view showing another embodiment of the wire connecting device with exchangeable securing member for electric connection terminal assembly according to the present invention; and
FIG. 8 is an exploded perspective view showing another embodiment of the exchangeable securing member according to the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Now, the preferred embodiments of the present invention will be described below with reference to the accompanying drawings.
FIG. 1 is an exploded perspective view showing an embodiment of the wire connecting device with exchangeable securing member for an electric connection terminal assembly according to the present invention, which is mounted on an angle iron 10. The angle iron 10 takes a U-shaped form. On each edge of the angle iron 10 is provided a protruded fixing rim 11, and at the each side of the angle iron 10 is formed a fixing hole 12, into which a fixing bolt 13 is inserted.
An electric connection terminal assembly 500 comprises a plurality of wire connecting devices 200 mounted on the angle iron 10. In each of the wire connecting devices 200 are provided a connecting plate 100, actuated by a push button 40, and a connection base 50. On each side of the wire connecting device 200 is formed a connecting hole 42, into which one peeled end of the leading wire 600 is inserted. The one peeled end of the leading wire 600 is connected to the connection base 50. The operation of the wire connecting device 200 is as follows. By the repulsive force of a spring 110 arranged in a spring groove 44 formed at the lower part of the connecting plate 100, the connecting plate 100 is forced to rise upwards. For the turning portion of the connecting plate 100, a hinge pin 43 is engaged into a hinge hole 101 of the connecting plate 100, and a connecting end 102 of the connecting plate 100 contacts with a connecting piece 51 of the connection base 50.
And a connecting member 70 is inserted into a connecting groove 70-1 formed continuously at the lower part of a cap groove 35 formed at the upper part of the wire connecting device 200, so that the connecting member 70 keeps in contact with the connection base 50.
A partition 38 formed at one side of the connecting groove 70-1 is inserted into a spacing groove 72 of the connection member 70. A connecting screw 80 is engaged into a nut 60 via a connecting hole 71 and a connecting hole 53 formed at a connecting portion 52.
The electric connection terminal assembly 500 constructed as mentioned above is mounted on the angle iron 10 by means of the securing member 20 attached to the bottom of the wire connecting device 200. Wire connecting devices 200 are coupled to each other by engagement of protrusions 33 formed on the front surface and grooves 34 formed on the rear surface of the wire connecting device 200.
A plurality of the wire connecting devices 200 coupled as mentioned above are mounted on the angle iron 10 by the securing members 20. On the top of each securing member 20 is provided a T-shaped protrusion 24, which is inserted into a T-shaped groove 31 formed at the lower part of the wire connecting device 200. To eliminate the possibility of detachment between the T-shaped protrusion 24 and the T-shaped groove 31, a locking groove 32 is formed at the entrance of the T-shaped groove 31, and a fixing portion 24-1 is provided on the inner side of the T-shaped protrusion 24.
At the lower part of the securing member 20 is formed an angle iron groove 21, which is engaged with the protruded fixing rim 11. On the opposite side of the angle iron groove 21 is provided a fixing projection 22 formed elastically at the release lever 23, by which the securing member 20 can be mounted on or detached from the angle iron 10 easily and conveniently.
The wire connecting device 200 can be mounted on the angle iron 10 without any rolling by a mounting bracket 130 having an angle iron groove 131, which is engaged with the protruded fixing rim 11 of the angle iron 10, formed at the lower part thereof, and a supporting piece 132 formed elastically and in the form of the protrusion at the upper part thereof. Before fixing by the mounting bracket 130, a support plate 120 is inserted between the wire connecting device 200 and the mounting bracket 130 such that the protrusions 33 formed on the wire connecting device 200 are inserted into connecting grooves 34-1 formed on the support plate 120. Subsequently, the mounting bracket 130 is fixed to the angle iron 10 so that the wire connecting device 200 is prevented from rolling on the angle iron 10, as shown in FIG. 5.
A cap 90 having serial numbers 93 printed thereon is inserted into a cap groove 35 formed on the central upper part of the wire connecting device 200. A cap projection 92 provided on the lower part of the cap 90 is engaged with a projection 37 of the cap groove 35 formed on the inner wall of the cap groove 35, and a stop 36 is formed on the upper part of the projection 37 of the cap groove 35 so that the stop 36 fits into a connecting groove 94 formed on the edge of the cap 90. Therefore, the serial numbers 93 correspond to the positions of the connected wires 600.
The above descriptions relate to the wire connecting device 200 mounted on equipment using the angle iron 10. In some occasions, however, the wire connecting device 200 can be mounted directly on the board of the equipment without using the angle iron 10 as mentioned above. In this case, the securing member 20 is not used.
Another embodiment of the wire connecting device without the securing member is illustrated in FIG. 2 and FIG. 6. According to this embodiment, two mounting brackets 130-1 having a support plate 120-1 formed integrally are arranged at both ends of the wire connecting device 200. The wire connecting device 200 is mounted to the board of the equipment by screwing the mounting bolt 13-1 into the board via a mounting hole 12-1 formed at the one end of the mounting bracket 130-1.
In the wire connecting device 200 mounted as described above, however, the middle portions are not supported securely as compared with the wire connecting device 200 mounted securely to the angle iron 10, thus resulting in disconnection of the leading wire 600 from the wire connecting device 200, if the wire connecting device 200 is not provided with the connection member 70.
To avoid the disconnection as mentioned above, a connection member strip 70-2 corresponding to the connection 70 is inserted into the connecting groove 70-1 in which the connection member 70 was located. The connecting groove 70-1 is engaged with a connecting bar 70-3 formed integrally on the bottom of the connection strip 70-2, thus preventing the middle portion from getting loose, as illustrated in FIG. 7.
Now, the operation of the present invention will be described in detail.
First of all, mounting with the angle iron 20 will be described. Generally, the securing member 20 of the wire connecting device 200 mounted on the angle iron 10 may have various structures corresponding to various shapes and sizes of the angle irons 10 which several manufacturers use to mount on equipment. Previously, the connecting body and support member were integrally formed, thus raising manufacturing costs.
On the contrary, according to the present invention, various kinds of the securing members 20 can be made separately, and afterwards the securing member 20 is attached to the existing connecting body 30, thus the manufacturing costs can be reduced.
That is to say, the T-shaped protrusion 24 provided on the upper part of the securing member is inserted into the T-shaped groove 31 formed on the bottom of the connecting body 30 so that the securing member 20 is attached to the connecting body 30, an act which provides the same result as the connecting body 30 and the securing member 20 produced as a single body.
The securing member 20, which is manufactured in different shapes and sizes, can be attached to the corresponding connecting body 30. Another example of the securing member is illustrated in FIG. 8. The securing member 20' as shown in FIG. 8 is similar to the securing member 20 as shown in FIG. 1 except for its size. Accordingly, the detailed descriptions thereof is omitted.
The wire connecting device 200 mounted on the angle iron 10 is applicable to large-scale equipment in which at least ten pieces of the wire connecting device are to be mounted, such as a telephone connection terminal box or electric control box supplying current to large-scale equipment.
Meanwhile, when the wire connecting device 200 is mounted to a small-scale piece of equipment or control box, the angle iron 10 is not necessarily required since the wire connecting devices 200 are small in number. In this case, the wire connecting device can be supported by engagement of protrusions 33 formed on the front surface of the connecting body 30 and grooves 34 formed on the rear surface of the wire connecting device 200. The wire connecting device 200 can further be fixed by the mounting bracket 130-1. Therefore, only the wire connecting device 200 can be used without the securing member 20.
As described above, the wire connecting device is obtained from the combination of the single type of connecting body and one securing member selected from various shapes and sizes of the securing members manufactured based upon the shapes and sizes of the angle irons to be used, the connecting body and the securing member being manufactured separately, thus the manufacturing costs can be reduced.
It is to be understood that the forms of the invention herewith shown and described are to be taken as illustrative embodiments of the same, and that various changes in the shape, size, and arrangement of parts, as well as various procedural changes, may be resorted to without departing from the spirit of the invention. | A wire connecting device includes an electrically conductive connection base and two spring-loaded connection plates for holding wires against the connection base. The connecting device is configured to be mounted in two different ways. The device may be mounted directly to a mounting surface by using mounting brackets on either side of the device that fit protrusions and grooves on the device. Alternatively, the device may be mounted to an angle iron by using a securing member shaped to mate with both the device and the angle iron. An electrically conductive connecting member couples the device to one or more similar connecting devices or, alternatively, a connecting member provides structural support between the device and at least one other similar connecting device. | 7 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to the method for fabricating thin film transistor display device that possesses the advantages of planarized surface on the pixel region, simplified fabrication process and enhanced production yield.
2. Description of Related Arts
The transfer fabrication process enables thin film devices to be created on substrates which would otherwise be impossible with the present semiconductor fabrication technique. A thin film transistor display device is fabricated through a transfer process, which claims to possess good device performance after transferring a semiconductor component onto a plastic substrate.
With reference to FIGS. 12 A˜F, a semiconductor component is fabricated through a series of steps: providing a first transfer substrate ( 50 ); forming a sacrificial layer ( 501 ) on top of the first transfer substrate ( 50 ); forming a thermal insulation layer ( 51 ) over the sacrificial layer ( 501 ); forming a semiconductor film ( 52 ) over the thermal insulation layer ( 51 ); forming a first dielectric layer ( 53 ) over the semiconductor film ( 52 ); forming a gate electrode layer ( 56 ) over the first dielectric layer ( 53 ), thus completing the fabrication of a semiconductor component on the first substrate ( 50 ).
Afterwards, the semiconductor component is integrated with a transparent electrode layer to form an integrated driver circuit through a series of steps: forming a second dielectric layer ( 54 ) over the semiconductor component; forming a first passivation layer ( 55 ) over the second dielectric layer ( 54 ); forming a transparent electrode layer ( 57 ) on top the first passivation layer ( 55 ), where the transparent electrode ( 57 ) is connected to the semiconductor component after patterning as shown in FIG. 12A; forming a second passivation layer ( 60 ) over the first passivation layer ( 55 ) and the transparent electrode ( 57 ); bonding a supporting substrate ( 61 ) onto the second passivation layer ( 60 ) as shown in FIG. 12 B.
Then, a second substrate ( 70 ) is glued on top of the semiconductor component, as shown in FIG. 12E, for transferring the semiconductor component from the first substrate ( 50 ) to the second substrate ( 70 ); heat is applied on the sacrificial layer ( 501 ) through laser irradiation to cause the sacrificial layer ( 501 ) to crack when an hydrogen explosion occurs on the inner surface of the first substrate ( 50 ) and the semiconductor component will detach from the surface of the first substrate ( 50 ) as shown in FIGS. 12 C & D (Since the sacrificial layer ( 501 ) is made with non-crystalline silicon film carrying hydrogen atoms, the laser beam creates thermal heat raising the internal temperature, and causes a hydrogen explosion in the thermal process); finally, the supporting substrate ( 61 ) and the second passivation layer ( 60 ) are removed to expose the transparent electrode ( 57 ) as shown in FIG. 12 F.
The above process involves pre-forming of the semiconductor component over the first transfer substrate ( 50 ) and then transferring the semiconductor component from the first substrate ( 50 ) onto the second substrate ( 70 ) through a thermal process. The semiconductor component to be created on the first substrate can be thin film transistor (TFT), metal oxide semiconductor (MOS), metal insulator metal capacitor (MIM) or thin film diode (TFD). However, the above fabrication process still has several shortcomings:
Too many transfer substrates: from the formation of the semiconductor component to the successful transfer of the semiconductor component onto the final substrate, at least three transfer substrates are needed.
Complex process and high process costs: using so many substrates in the process also entails complex processing steps, and furthermore the support substrate and the temporary protective layer will be discarded after one-time use in the thermal process. The above process is only part of the complete process which should further include the steps of forming the optical component and aligning the semiconductor component and the optical component.
Raised surface on the pixel electrode: since the pixel electrodes are formed under high temperature, the raised surface layer will cause uncontrolled electric discharge at the pointed edges resulting in abnormal white points on the display screen.
The fabrication process for thin film transistor display devices can be further improved to simplify the process and lower the process costs.
SUMMARY OF THE INVENTION
The main object of the present invention is to provide a method for fabricating thin film transistor display device by an economical means, whereby an integrated driver circuit with both the semiconductor component and the optical component can be successfully transferred from a first substrate onto a second substrate through a one-time thermal process, without degradation of device performance and consuming no substrates in the process. Since the semiconductor component and the optical component are formed and integrated on the first substrate before the transfer process, there is no need of further alignment. Also, the fully planarized surface of the pixel electrode can enhance the quality of display image.
The fabricating process comprises the steps of:
forming a pixel electrode directly over the sacrificial layer of the first substrate;
forming a semiconductor component on top of the pixel electrode layer;
performing testing on the semiconductor component to confirm the electrical characteristics;
forming an optical component, where the materials can be color conversion materials, filtering lens, polarizing film, light enhancing film, diffusion film, angle focusing film, wide angle lens, anti-reflection and reflection film, light absorption film, or a combination of the above, over the semiconductor component, thus forming an integrated driver circuit made up of a semiconductor component and an optical component on the same surface of the first substrate;
providing a second substrate for gluing onto the optical component on the first substrate;
applying heat on the back side of the first substrate to cause the surface of the sacrificial layer to crack and the semiconductor component and optical component to detach from the first substrate in a thermal process; and
etching away the pixel electrode originally formed on the first substrate to expose the pixel region, thus completing the fabrication of the thin film transistor display device.
Since the semiconductor component and the optical component are fully integrated on the first substrate before the thermal process, there is no need of further alignment of the two components after successful transfer onto the second substrate. It can also be observed that the pixel region electrodes fully planarized to produce good display images. No protective layer and supporting substrate are used in the whole process, thus simplifying the fabrication and reducing the process costs.
The features and structure of the present invention will be more clearly understood when taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1A-1F represent the fabrication process for a thin film transistor display device in accordance with the first embodiment of the invention;
FIGS. 2A-2C represent the fabrication process for a thin film transistor display device in accordance with the second embodiment of the invention;
FIGS. 3A-3C represent the fabrication process for a thin film transistor display device in accordance with the third embodiment of the invention;
FIGS. 4A-4C represent the fabrication process for a thin film transistor display device in accordance with the fourth embodiment of the invention;
FIGS. 5A-5C represent the fabrication process for a thin film transistor display device in accordance with the fifth embodiment of the invention;
FIGS. 6A and 6B represent the fabrication process for a thin film transistor display device in accordance with the sixth embodiment of the invention;
FIGS. 7A-7C represent the fabrication process for a thin film transistor display device in accordance with the seventh embodiment of the invention;
FIGS. 8A-8C represent the fabrication process for a thin film transistor display device in accordance with the eighth embodiment of the invention;
FIGS. 9A-9C represent the fabrication process for a thin film transistor display device in accordance with the ninth embodiment of the invention;
FIGS. 10A-10C represent the fabrication process for a thin film transistor display device in accordance with the tenth embodiment of the invention;
FIGS. 11A-11C represent the fabrication process for a thin film transistor display device in accordance with the eleventh embodiment of the invention; and
FIGS. 12A-12F represent the fabrication process for a thin film transistor display device in the prior art, only showing the part for the semiconductor component.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The present invention enables the transfer of a thin film device such as an integrated semiconductor and an optical component from the original substrate onto a second substrate through a hydrogen thermal process using an economical means, without degradation of device performance.
FIGS. 1A-1F show the fabrication process for a thin film transistor display device as practiced in the first embodiment of the invention, which includes the steps of:
providing a first substrate ( 10 ), which can be made of silicon, plastic, glass, or quartz;
forming a sacrificial layer ( 101 ) over the first substrate ( 10 ), wherein the sacrificial layer ( 101 ) is made from amorphous silicon material, containing many hydrogen atoms to cause combustion under high temperature;
forming an etching stop layer ( 102 ) over the sacrificial layer ( 101 ) for protection of a semiconductor component in etching and polishing processes, wherein the etching stop layer ( 102 ) can be made from materials such as silicon nitride, silicon oxide, diamond or diamond-like carbon materials;
forming a passivation layer ( 103 ) over the etching stop layer ( 102 );
forming a semiconductor film ( 11 ) over the passivation layer ( 103 );
patterning the semiconductor film ( 11 ) over the passivation layer ( 103 ) to define the active region, and ion doping to define a source and a drain region for the semiconductor component;
forming a first dielectric layer ( 13 ) is formed over the passivation layer ( 103 ) and the semiconductor film ( 11 ),
patterning the first dielectric layer ( 13 ) to create a gate insulating layer ( 13 a ) corresponding to a gate electrode ( 14 ) to be described below;
forming a gate electrode layer ( 14 ) over the gate insulating layer ( 13 );
forming a second dielectric layer ( 141 ) over the gate electrode layer ( 14 );
forming a pixel electrode layer ( 12 ) over the passivation layer ( 103 );
connecting the pixel electrode layer ( 12 ) to the semiconductor film ( 11 );
forming an optical component layer ( 15 ) using materials such as color resist, wide viewing angle layer, organic light emitting diode, polymer light emitting diode, polarizing film, light enhancing film, angle focusing film, compensation film, anti-reflection film, light absorption film, or a combination of the above;
bonding a second substrate ( 20 ) overlying the optical component ( 15 ) originally created on top the first substrate ( 10 ), which can be implemented by means of direct bonding, anodic bonding, lower temperature bonding, intermediate bonding, adhesive bonding, or laser melting, where the bonding can be performed partially or selectively as shown in FIG. 1B;
applying heat on the back side of the first substrate ( 10 ) or over selected portions using the high temperature laser annealing or pulse type fast annealing technique to cause the sacrificial layer ( 101 ) over the first substrate ( 10 ) to crack when a hydrogen explosion occurs on the inner surface of the sacrificial layer ( 101 ), as shown in FIG. 1C, such that the sacrificial layer ( 101 ) is cracked and the semiconductor and optical components become detached for transferring onto the second substrate ( 20 ) as shown in FIGS. 1D & E;
removing the etching stop layer ( 102 );
patterning the passivation layer ( 103 ) leaving only the portion to correspond to the semiconductor component, such that the planarized pixel electrode ( 12 ) can be exposed as shown in FIG. 1 F.
The fabrication processes for the thin film transistor will be slightly modified in the following seven embodiments to be described below:
In the first embodiment, the materials for fabricating semiconductor component can be thin film transistor (TFT), metal oxide semiconductor (MOS), metal insulator metal capacitor (MIM), or thin film diode (TFD) built on top of a substrate made from amorphous silicon (a-Si) or glass materials through crystallization. After the semiconductor component, that is the thin film transistor, is formed, the optical component matching the particular requirements for a display monitor is coupled onto the semiconductor component to form an integrated driver circuit. With a single-step thermal process, the integrated semiconductor and optical component is transferred from the first substrate ( 10 ) onto the second substrate ( 20 ), with no need of further alignment for these two components. Since the pixel electrode ( 12 ) is formed directly over the first substrate ( 10 ), the pixel electrode ( 12 ) already possesses a fully planarized surface after the removal of the first substrate ( 10 ).
FIGS. 2 A˜C schematically illustrate the fabrication of the thin film transistor display device as practiced by the second embodiment of the invention. The process is basically identical to that employed by the first embodiment, with the exception that the sacrificial layer ( 101 ) and the passivation layer ( 103 ) are respectively formed over the first substrate ( 10 ), replacing the etching stop layer (not shown in the diagram). When the semiconductor component and optical components are detached from the first substrate ( 10 ), it only takes a patterning process on the passivation layer ( 103 ) to expose the pixel electrode ( 12 ).
FIGS. 3 A˜C schematically illustrate the fabrication of thin film transistor display device as practiced by the third embodiment of the invention. The process is basically identical to that in the first embodiment, with the exception that etching back is not needed on the first dielectric layer ( 13 ) in forming the gate insulating layer ( 13 a ), and the pixel electrode ( 12 ) is directly formed on the first transparent dielectric layer ( 13 ). Lithography is respectively performed on the etching stop layer ( 102 ), passivation layer ( 103 ), and the first transparent dielectric layer ( 13 ) to expose the pixel electrode ( 12 ).
FIGS. 4 A˜C schematically illustrate the thin film transistor display device as practiced by the fourth embodiment of the invention, wherein the features of the second and third embodiments are all incorporated in this embodiment, that means it does not need the passivation layer (not shown in the diagram), and the pixel electrode layer ( 12 ) is formed on top of the first dielectric layer ( 13 ).
FIGS. 5 A˜C schematically illustrate the thin film transistor display device as practiced by the fifth embodiment of the invention, wherein the fabrication process is basically identical to that of the first embodiment, with the exception that the sacrificial layer ( 101 ), an alignment layer ( 104 ) and the passivation layer ( 103 ) are respectively formed over the first substrate ( 10 ), wherein the pixel electrode ( 12 ) is formed over the alignment layer ( 104 ).
FIGS. 6A and 6B schematically illustrate the fabrication process of thin film transistor display device practiced by the sixth embodiment of the invention, wherein the fabrication process is basically identical to that of the first embodiment, with the exception that only the sacrificial layer ( 101 ) and the alignment layer ( 104 ) are respectively formed over the first substrate ( 10 ), and the pixel electrode ( 12 ) is formed over the alignment layer ( 104 ).
FIGS. 7 A˜ 7 C schematically illustrate the fabrication of the thin film transistor display device as practiced by the seventh embodiment of the invention. The fabrication process is basically identical to that of the first embodiment, with the exception that the sacrificial layer ( 101 ), the etching stop layer ( 102 ), the alignment layer ( 104 ), and the patterned passivation layer ( 103 ) are respectively formed on top of the first substrate ( 10 ), and the pixel electrode ( 12 ) is formed over the alignment layer ( 104 ).
Still another variation on the fabrication process for the thin film transistor display device is different from those described above in that some of the processing steps are carried out in the reverse order; that is the pixel electrode ( 12 ) is formed on top of the first substrate ( 10 ) before the formation of the thin film transistor. Referring to FIGS. 8 A˜ 8 C, a sacrificial layer ( 101 ) is first formed on top of the first substrate ( 10 ), then a etching stop layer ( 102 ) is formed over the sacrificial layer ( 101 ), then a pixel electrode layer ( 12 ) is formed over the etching stop layer ( 102 ), and then a passivation layer ( 103 ) is formed over the pixel electrode layer ( 12 ) for fabrication of thin film transistor over the passivation layer ( 103 ). After successful testing of the electrical characteristics of the semiconductor component, the formation of an optical component ( 15 ), the transfer process and the lithography process are respectively performed to produce the thin film transistor display device.
FIGS. 9 A˜ 9 C schematically illustrate the fabrication of the thin film transistor display device as practiced by the ninth embodiment of the invention. The process is slightly different from the eighth embodiment in that it does not need the etching stop layer (not shown in the diagram). Referring to FIGS. 10 A˜ 10 C, the fabrication process as practiced by the tenth embodiment of the invention is different from the eighth embodiment in that an alignment layer ( 104 ) is used instead of the etching stop layer ( 102 ); or else, it could also be implemented by forming a alignment layer ( 104 ) directly over the etching stop layer ( 102 ) as shown in FIGS. 11 A˜ 11 C.
The present invention is characterized in that the semiconductor component and optical component are fully integrated on the first substrate with no need of further alignment in subsequent process.
The present invention is also characterized in that thin film device possesses good electrical and optical characteristics without degradation of device performance after the transfer process, and the first substrate can be used again with no waste of substrates.
The present invention is also characterized in that the pixel electrode is formed in the semiconductor fabrication process and connected internally to the semiconductor component, such that the semiconductor component can be directly exposed after the transfer process as disclosed in the previous embodiment; alternatively, through patterning of the sacrificial layer and the passivation layer the semiconductor component becomes exposed with a planarized surface, with no need of further patterning for the pixel electrode. This facilitates the filling of light materials such as liquid crystal, organic light emitting diode (OLED) or polymer light emitting diode (PLED) to produce a good display quality.
In sum, the present invention is performed with two transfer substrates; the semiconductor component and the optical component are formed and integrated on the same substrate, and through one-time thermal process the integrated device is transferred to the second substrate without degradation of device performance; the original transfer substrate where the semiconductor and optical component are initially formed can be reused, as opposed to the conventional thermal process which requires at least three substrates.
The foregoing description of the preferred embodiments of the present invention is intended to be illustrative only and, under no circumstances, should the scope of the present invention be so restricted. | The present invention makes it possible to transfer thin film devices such as integrated semiconductor and optical components from a first substrate onto a second substrate through a thermal process at high temperature, without degradation of device performance. Other devices can be fabricated thereafter on the other side of the second substrate. Since the semiconductor and optical components can be transferred onto the second substrate in a single-step thermal process, in comparison with prior art the number of transfer substrates needed in the fabrication process can be effectively reduced, thus simplifying the fabrication process and realizing cost reduction. | 7 |
FIELD OF THE INVENTION
[0001] The present invention relates generally to serial communications. More specifically, the present invention relates to methods and systems for clock and data recovery in serial communications links.
BACKGROUND OF THE INVENTION
[0002] Serial communications is a process that involves sequentially communicating a stream of data bits over a serial communications link. Serial communications is used in a wide variety of applications, many of which are defined by their own unique standards. A few examples include, the Serial Advanced Technology Attachment (SATA) standard, which sets forth serial communication specifications for transferring data between a computing device (e.g., a personal computer) and a data storage device (e.g., a computer hard drive); the Universal Serial Bus (UBS) standard, which specifies the transfer of data between a computing device and a peripheral device; and the DigRF standard, which specifies a digital serial communications link between a baseband controller and radio in a cellular handset.
[0003] FIG. 1 is a drawing of a typical two-way serial communications system 100 having differential upstream and downstream serial links 102 and 104 . The two-way serial communications system 100 includes an uplink line driver (LD) 106 , an uplink line receiver (LR) 108 , a downlink LD 110 , and a downlink LR 112 . The uplink LD 106 is configured to transmit a digital data stream comprised of a sequence of data bits upstream to the uplink LR 108 , via the upstream serial link 102 . Similarly, the downlink LD 110 is configured to transmit a digital data stream downstream to the downlink LR 112 , via the downstream serial link 104 .
[0004] The uplink LD 106 is clocked by a first high-frequency clock, and the downlink LD 110 is clocked by an independently generated second high-frequency clock. The first high-frequency clock is generated by a first clock synthesizer 114 , based on a first low-frequency clock provided by a first oscillator 116 . The second high-frequency clock is generated by a second clock synthesizer 118 , based on a second low-frequency clock provided by a second oscillator 120 .
[0005] Because the first and second high frequency clocks are not transmitted along with the data streams, and the LRs 108 and 112 are not otherwise synchronized with the LD clocks, some phase alignment mechanism must be provided to establish proper phase relationships between the local clocks at the LRs 108 and 112 and the data bits received by the LRs 108 and 112 . First and second clock recovery circuits 122 and 124 , which are coupled to the uplink and downlink LRs 108 and 112 , respectively, serve to perform these phase alignment processes.
[0006] It is not uncommon for the phase or frequency of data streams received by one of the LRs 108 and 112 to change or fluctuate over time. To track these changes and fluctuations, each of the clock recovery circuits 122 and 124 is typically implemented within a phase-locked loop (PLL). FIG. 2 is a drawing of a typical PLL-based (or “tracking”) clock and data recovery (CDR) circuit 200 . The PLL-based CDR circuit 200 comprises a sampling phase detector 202 , a charge pump 204 , a loop filter 206 , and a multi-phase voltage controlled oscillator (VCO) 208 . The multi-phase VCO 208 operates to generate a multi-phase set of sampling clocks, for example, clk 1 , clk 2 , clk 3 . The sampling phase detector 202 is configured to receive the multi-phase set of sampling clocks, clk 1 , clk 2 , clk 3 , and use the clocks to sample the incoming data stream. Based on the phase and frequency relationship of the multi-phase set of sampling clocks, clk 1 , clk 2 , clk 3 and the sampled data, the sampling phase detector 202 generates phase error pulses, Pu and Pd. As explained in more detail below, the charge pump 204 and loop filter 206 respond to these phase error pulses, Pu and Pd, by increasing or decreasing the value of a control voltage signal, ΔV in , applied to the multi-phase VCO 208 . The multi-phase VCO 208 responds to changes in the control voltage signal, ΔV in , by increasing or decreasing the frequency of the multi-phase set of sampling clocks. The frequency-corrected multi-phase set of sampling clocks is then fed back to the sampling phase detector 202 , which then samples the incoming data stream using the frequency corrected multi-phase set of sampling clocks. The above described process is repeated again and again until the phase error between the multi-phase set of sampling clocks and the clock being recovered from the incoming data is reduced to zero (or some acceptably small amount).
[0007] The sampling phase detector 202 in the PLL-based CDR circuit 200 is often comprised of what is known as a “bang-bang” phase detector, a circuit diagram of which is shown in FIG. 3A . The bang-bang phase detector 300 includes first, second and third flip-flops 302 - 1 , 302 - 2 and 302 - 3 , which are configured to sample the incoming data stream according to the multi-phase set of sampling clocks, clk 1 , clk 2 , clk 3 . Each of the sampling clocks in the multi-phase set of sampling clocks, clk 1 , clk 2 , clk 3 , has the same nominal frequency. However, each individual sampling clock in the set is offset in phase relative to other sampling clocks in the set. More specifically, and as illustrated in the timing diagrams in FIG. 3B , the second sampling clock, clk 2 , is delayed relative to the first sampling clock, clk 1 , by ninety degrees, and the third sampling clock, clk 3 , is delayed relative to the first sampling clock, clk 1 , by one hundred eighty degrees.
[0008] The input data stream is sampled by the first, second and third flip-flops 302 - 1 , 302 - 2 and 302 - 3 upon the occurrences of rising edges of the three sampling clocks, clk 1 , clk 2 and clk 3 . The resulting data samples are coupled to first and second exclusive-OR (XOR) gates 304 - 1 and 304 - 2 . In addition to serving as a sampling clock for the third flip-flop 302 - 3 , the third sampling clock, clk 3 , is used to control the enable of the first and second XOR gates 304 - 1 and 304 - 2 , and to synchronize the phase error pulses, Pu and Pd. A delay element 306 having a delay of equal to one flip-flop delay is inserted in the path of third sampling clock, clk 3 , so that the enable signals and phase error pulses, Pu and Pd, are properly timed.
[0009] The multi-phase set of sampling clocks, clk 1 , clk 2 , clk 3 , is configured in this case so that data transitions in the input data stream occur either between the rising edges of the first and second sampling clocks, clk 1 and clk 2 , or between the rising edges of the second and third sampling clocks, clk 2 and clk 3 . If a data transition occurs between the rising edges of the first and second sampling clocks, clk 1 and clk 2 , the frequency of the clock being recovered is deemed to be lagging the data (frequency too low), and a phase error pulse, Pu, is generated at the output of the first XOR gate 304 - 1 . On the other hand, if a data transition occurs between the second and third sampling clocks, clk 2 and clk 3 , the frequency of the clock being recovered is deemed to be leading the data (frequency too high) and a phase error pulse, Pd, is generated at the output of the second XOR gate 304 - 2 .
[0010] The Pu and Pd phase error pulses generated by the first and second XOR gates 304 - 1 and 304 - 2 are used to control the charge pump 204 and loop filter 206 . As illustrated in FIG. 3C , a positive current source responds to Pu phase error pulses by sourcing current to the loop filter 206 , and a negative current source responds to Pd phase error pulses by sinking current from the loop filter 206 . Because the loop filter 206 operates as an integrator, the VCO control voltage, ΔV in , increases or decreases depending on whether the charge pump 204 receives a Pu phase error pulse or a Pd phase error pulse respectively. More particularly, receipt of a Pu phase error pulse will result in an acceleration of the VCO output phase, while receipt of a Pd phase error pulse will result in a deceleration of the VCO output phase.
[0011] While the PLL-based CDR circuit 300 is capable of regenerating a recovered clock at the LR of a serial communications link, actual data cannot be sent to the LR until the frequency correction process (i.e., “acquisition” process) described above has completed. In other words, before actual data is sent over the link, the PLL must operate to lock to a training sequence (or “header”) having a predefined transition pattern that facilitates the acquisition process. Only until after the acquisition process is completed can actual data be reliably communicated over the communications link to the LR.
[0012] Because the PLL-based CDR circuit acquisition process is an averaging process implemented in a feedback and control system, it takes on the order of a thousand training sequence bits (i.e., a thousand “unit intervals” (UIs) or more) to complete the acquisition process. This large “header overhead” is highly undesirable since it not only delays actual data communications, but also results in wasted power. To avoid having to unnecessarily repeat the time consuming acquisition process, PLL-based CDR circuits are also typically configured to run continuously, even when the communication link is idle. Unfortunately, running the PLL at all times wastes additional power.
[0013] Another problem with the PLL-based CDR circuit 300 is that it is fundamentally incapable of operating in the presence of large frequency errors that can exist between the frequency of the clock being recovered and the multi-phase set of sampling clocks, clk 1 , clk 2 , clk 3 . This is attributable to limits on the possible loop bandwidth of the PLL. The actual frequency of the clock being recovered must therefore be very close in frequency to the frequency of the multi-phase set of sampling clocks, clk 1 , clk 2 , clk 3 , or the PLL will be unable to acquire or lock to the data in the received data stream.
[0014] Finally, in order for the PLL-based CDR circuit 300 to work properly, the data streams received by the LRs 108 and 112 must exhibit jitter-open eye patterns. In other words, the peak-to-peak jitter in the data stream received by the LRs 108 and 112 must remain less than a single UI. Otherwise, the PLL-based CDR circuit 300 will be either incapable of recovering the clock and data or the recovered data will have an unacceptably high error rate.
[0015] Given the foregoing problems and limitations of the prior art, it would be desirable to have systems and methods for recovering clocks and data in serial communications systems that: are not burdened by large header overheads and time consuming acquisition processes; do not require a PLL or feedback to recover the clocks and data; continue to operate properly even when large frequency errors and high jitter are present; and do not consume large amounts of unnecessary power.
BRIEF SUMMARY OF THE INVENTION
[0016] Methods and systems for recovering clock and data in data streams communicated over serial communications links are disclosed. An exemplary clock and data recovery method includes sampling a received data stream using a multi-phase set of sampling clocks and, upon the occurrence of a data transition in the received data stream, designating one of the sampling clocks of the multi-phase set of sampling clocks as a recovered clock. The designated recovered clock is then used to recover data bits in the data stream. According to one aspect of the invention, designating the first sampling clock from among the multi-phase set of sampling clock is performed independent of data transitions in the data stream that have occurred prior to the occurrence of the data transition used to designate the recovered clock.
[0017] An exemplary serial communications receiver system includes a line receiver configured to receive a data stream from a serial communications link and an instant-acquisition clock and data recovery circuit coupled to the line receiver. The instant-acquisition clock and data recovery circuit includes a time interval detector and a sampling clock selector. The time interval detector is operable to sample the data stream received by the line receiver according to a multi-phase set of sampling clocks. The sampling clock selector is operable to designate one of the sampling clocks of the multi-phase set of sampling clocks as a recovered clock, based on a data transition in the received data stream detected by the time interval detector. The clock selector is configured to designate the sampling clock as the recovered clock independent of data transitions in the data stream that may have occurred prior to the data transition detected by the time interval detector.
[0018] The instant-acquisition CDR methods and systems of the present invention offer a variety of advantages and benefits over prior art CDR approaches. First, clock recovery and data alignment are completed nearly instantaneously following detection of a transition in the received data stream, e.g., within a timeframe that is less than a bit time (or unit interval). The methods and systems do not rely on or require a PLL configured to perform an averaging process to recover the clock and data. Therefore, lengthy acquisition training sequences or headers are avoided by the methods and systems of the present invention. Second, the instant-acquisition methods and systems of the present invention operate even in the presence of a large frequency error. In prior art PLL-based CDR circuits, the clock being recovered from the incoming data stream must be very close in frequency to the local sampling clock of the receiver receiving the data stream. This frequency agility is highly desirable since accurate data recovery can be achieved even in the presence of large amounts of noise and/or jitter. Moreover, because an averaging process is not needed to recover the clock or align the data, a jitter-open eye is not required to accurately and correctly detect and recover the clock and data using the methods and systems of the present invention. Finally, because clock recovery and data alignment are completed instantly, and do not require a long training sequence or header, the instant-acquisition CDR circuits of the present invention can be powered down whenever the communications link is idle (i.e., not transmitting data). This power conserving advantage over prior art approaches is particularly beneficial in applications where the instant-acquisition CDR circuit is used to receive data over a serial communications link configured within a battery-powered communications device (e.g., as may be formed between a baseband controller and a radio in a cellular handset).
[0019] Further features and advantages of the present invention, as well as the structure and operation of the above-summarized and other exemplary embodiments of the invention, are described in detail below with respect to accompanying drawings, in which like reference numbers are used to indicate identical or functionally similar elements.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] FIG. 1 is a drawing of a typical two-way serial communication system;
[0021] FIG. 2 is a diagram of a conventional PLL-based (or “tracking”) clock and data recovery (CDR) circuit;
[0022] FIG. 3A is a diagram of a bang-bang phase detector used in the conventional PLL-based CDR circuit in FIG. 2 ;
[0023] FIG. 3B is a timing diagram of the multi-phase set of sampling clocks used to clock the bang-bang phase detector in FIG. 3A ;
[0024] FIG. 3C is a diagram of the charge pump and loop filter used in the conventional PLL-based CDR in FIG. 2 ;
[0025] FIG. 4 is a diagram of an instant-acquisition clock and data recovery (CDR) circuit, according to an embodiment of the present invention;
[0026] FIG. 5 is a timing diagram showing the phase relationships among the sampling clocks of the multi-phase set of sampling clocks, clk, Qclk, /clk, /Qclk, used by the instant-acquisition CDR circuit in FIG. 4 ;
[0027] FIG. 6 is a timing diagram showing time and phase relationships among an eye pattern of a data stream received by a line receiver (LR) in a serial communications system, an exemplary data bit sequence at the output of the LR, and the multi-phase set of sampling clocks, clk, Qclk, /clk, /Qclk;
[0028] FIG. 7 is a truth table showing the correspondence between the subintervals, W, X, Y and Z, in the timing diagram in FIG. 5 and selection of the sampling clocks of the multi-phase set of sampling clocks, clk, Qclk, /clk, /Qclk;
[0029] FIG. 8 is a timing diagram illustrating how a selected sampling clock from the multi-phase set of sampling clocks, clk, Qclk, /clk, /Qclk, is maintained in the absence of subsequent data transitions and when subsequent data transitions fall within the same subinterval Y;
[0030] FIG. 9 is a timing diagram illustrating how the decision and selection of a sampling clock from among the multi-phase set of sampling clocks, clk, Qclk, /clk, /Qclk, is made based on the most recent data transition, and illustrating how data is correctly and accurately detected even in the presence of a very large clock frequency error;
[0031] FIG. 10A is a subinterval transition diagram illustrating how adjacent data transition time subintervals in one direction (or the other) signify whether the frequency of the local multi-phase set of sampling clocks, clk, Qclk, /clk, /Qclk, is too high, too low, or correct;
[0032] FIG. 10B is a truth table illustrating how the various time subinterval transitions in the subinterval transition diagram in FIG. 10A are converted to frequency UP and DOWN commands; and
[0033] FIG. 11 is a diagram of an instant-acquisition CDR circuit similar to the instant-acquisition CDR circuit shown in FIG. 4 , but which also includes frequency-error-reduction circuitry, according to an embodiment of the present invention.
DETAILED DESCRIPTION
[0034] Referring to FIG. 4 , there is shown an instant-acquisition clock and data recovery (CDR) circuit 400 , according to an embodiment of the present invention. The instant acquisition CDR circuit 400 comprises first, second, third and fourth flip-flops 402 - 1 , 402 - 2 , 402 - 3 and 402 - 4 ; first, second, third and fourth exclusive OR (XOR) gates 404 - 1 , 404 - 2 , 404 - 3 and 404 - 4 ; a data path and clock phase selector 406 ; an aligned data multiplexer 408 ; and a recovered clock multiplexer 410 . Collectively, and as will be explained in detail below, the first, second, third and fourth flip-flops 402 - 1 , 402 - 2 , 402 - 3 and 402 - 4 and first, second, third and fourth XOR gates 404 - 1 , 404 - 2 , 404 - 3 and 404 - 4 comprise a time interval detector that is capable of achieving frequency acquisition and data alignment accurately and instantly upon receipt of the first data bit transition in a received data stream.
[0035] The first, second, third and fourth flip-flops 402 - 1 , 402 - 2 , 402 - 3 and 402 - 4 are configured to receive a multi-phase set of sampling clocks, which in this embodiment includes an in-phase sampling clock, clk, a quadrature sampling clock, Qclk, an inverse sampling clock, /clk, and an inverse-quadrature sampling clock, /Qclk. The first flip-flop 402 - 1 is configured to receive the in-phase sampling clock, clk; the second flip-flop 402 - 2 is configured to receive the quadrature sampling clock, Qclk; the third flip-flop 402 - 3 is configured to receive the inverse sampling clock, /clk; and the fourth flip-flop 402 - 4 is configured to receive the inverse-quadrature sampling clock, /Qclk. Each sampling clock in the multi-phase set of sampling clocks, clk, Qclk, /clk, /Qclk is set to a nominal or expected frequency that corresponds to the expected data rate of the data stream being sampled.
[0036] FIG. 5 is a timing diagram comparing the phase relationships among the sampling clocks of this multi-phase set of sampling clocks, clk, Qclk, /clk, /Qclk. The quadrature sampling clock, Qclk, is rotated (i.e., is shifted in phase) ninety degrees relative to the in-phase sampling clock, clk. The inverse sampling clock, /clk, is shifted in phase one hundred eighty degrees relative to the in-phase sampling clock, clk. And, the inverse-quadrature sampling clock, /Qclk, is shifted in phase two hundred seventy degrees relative to the in-phase sampling clock, clk. When configured in this manner, four clock edges appear in every three hundred sixty degree rotation of the multi-phase set of clocks, i.e., in every unit interval (UI). It should be pointed out here that, while a four-phase set of sampling clocks, and a corresponding four flip-flops and four XOR gates are shown and described in this exemplary embodiment, any number of clock phases and corresponding flip-flops and XOR gates may be used, as will be readily appreciated by those of ordinary skill in the art. Further, whereas XOR gates are used to perform the logic operations, other logic gate types or combinations of logic gate types may be alternatively used to implement the same or similar logic functions, as will also be appreciated by those of ordinary skill in the art.
[0037] Data samples transferred to the Q outputs of adjacent pairs of the first, second, third and fourth flip-flops 402 - 1 , 402 - 2 , 402 - 3 and 402 - 4 are coupled to the inputs of the first, second, third and fourth XOR gates 404 - 1 , 404 - 2 , 404 - 3 and 404 - 4 . The outputs of the first, second, third and fourth XOR gates 404 - 1 , 404 - 2 , 404 - 3 and 404 - 4 are then coupled to inputs W, X, Y and Z of the data path and clock phase selector 406 . The significance of the labels “W”, X”, “Y” and “Z” is discussed below. A multiplexer control signal at the output of the data path and clock phase selector 406 is coupled to the control inputs of both the aligned data multiplexer 408 and the recovered clock multiplexer 410 .
[0038] According to an embodiment of the invention, the instant acquisition CDR circuit 400 is coupled to an LR within a serial data communication system, and is operable to sample a data stream, LRout, appearing at the output of the LR. FIG. 6 shows the timing relationships among an eye pattern of a data stream (LRin) received by the LR, an exemplary squared-up sequence of bits (LRout) in the data stream appearing at the output of the LR, and the multi-phase set of sampling clocks, clk, Qclk, /clk, /Qclk. Sampling of the data stream occurs after the LR squares up the received data stream, e.g., by use of a comparator or limiter circuit.
[0039] The multi-phase set of sampling clocks clk, Qclk, /clk, /Qclk, is configured so that the rising edge of each sampling clock in the set occurs once in a UI of time, where a UI corresponds to an expected time duration of a single data bit in the received data stream. The sampling clock edges of the multi-phase set of sampling clocks, clk, Qclk, /clk, /Qclk, further define repeating sequences of subintervals, W, X, Y, Z. Upon the occurrence of a data transition occurring in one of the subintervals, W, X, Y or Z, one of the flip-flops 402 - 1 , 402 - 2 , 402 - 3 and 402 - 4 will change state and one of the XOR gates 404 - 1 , 404 - 2 , 404 - 3 and 404 - 4 will correspondingly change logic state. Which flip-flop and which XOR gate changes state depends on which of the subintervals, W, X, Y or Z, the data transition occurs. For example, if a data transition occurs within the subinterval W, as in FIG. 6 , the logic state of the second flip-flop 402 - 2 and the logic state of the second XOR gate 404 - 2 changes on the next rising edge of the quadrature clock, Qclk.
[0040] Based on the change in logic states of the XOR gates 404 - 1 , 404 - 2 , 404 - 3 and 404 - 4 , the data path and clock phase selector 406 generates a multiplexer control signal for the aligned data multiplexer 408 and the recovered clock multiplexer 410 . The recovered clock multiplexer 410 responds to the multiplexer control signal by selecting the sampling clock from among the multi-phase set of sampling clocks, clk, Qclk, /clk or /Qclk, that has a rising edge closest to the center of the data bit being sampled. For example, in the example shown in FIG. 6 , the inverse sampling clock, /clk, is selected, since following the data transition in subinterval W, the inverse sampling clock, /clk, has a rising edge that is most toward the center of the bit being sampled, compared to the rising edges of the other sampling clocks. FIG. 7 is a truth table showing the correspondence of the inverse sampling clock, /clk, to the subinterval W, as well as the correspondence of the other sampling clocks (clk, Qclk and /Qclk) to the other subintervals, X, Y and Z. The data path and clock phase selector 406 includes the logic circuitry for implementing the various entries in the truth table.
[0041] As mentioned in the previous paragraph, the aligned data multiplexer 408 also responds to the multiplexer control signal provided by the data path and clock phase selector 406 . Based on the value of the control signal applied to the aligned data multiplexer 408 , the data provided by the flip-flop that is clocked by the clock phase that has been selected as the recovered clock is selected. In the example shown in FIG. 6 , the data would be provided by the third flip-flop 402 - 3 . In this manner, the data stream is properly aligned with sampling clock that has been selected to be the recovered clock.
[0042] FIG. 8 is a timing diagram illustrating how a selection of a sampling clock from the multi-phase set of sampling clocks, clk, Qclk, /clk, /Qclk, is maintained in the absence of subsequent data transitions or when subsequent data transitions fall within the same subinterval (e.g., subinterval Y) in a later subinterval sequence. The first data transition in the data stream LRout is seen to occur in subinterval Y. Accordingly, based on the truth table in FIG. 7 , the data path and clock phase selector 406 generates a signal that selects the in-phase sampling clock, clk, as the recovered clock. The next data transition also occurs in subinterval Y, so the in-phase sampling clock, clk, is maintained as the recovered clock. If the data does not transition again before the occurrence of the next rising edge of the selected clock phase, the presently selected sampling clock is also maintained, as illustrated by the dashed ellipse encircling the rising edge of the in-phase sampling clock following the second data transition in LRout. In other words, the selected sampling clock decision is maintained between data transitions.
[0043] The timing diagrams in FIG. 8 also highlight that the clock and data recovery methods and systems of the present invention do not depend on past data transition events. Instead, they are performed as soon as a transition is detected in the incoming data stream, not as a result of an average of past data transitions as in prior art PLL-based CDR approaches.
[0044] Because the recovered clock and the aligned and sampled data are immediately determined following the occurrence of a data transition, and not by an averaging feedback process as in prior art PLL-based CDR approaches, the systems and methods of the present invention are able to correctly detect the data in the incoming data stream even with a very large clock frequency error. This is illustrated in FIG. 9 , where the data rate is about 15% higher than the data rate in the example in FIG. 8 . This frequency error is about 100 times greater than the error tolerable by prior art CDR approaches. The high data rate, compared to the frequencies of the local sampling clocks of the multi-phase set of sampling clocks, clk, Qclk, /clk, /Qclk, represents a very large frequency error. Despite the large frequency error of this example, the systems and methods of the present invention are able to correctly detect the data by rapidly selecting the most appropriate sampling clock from the multi-phase set of sampling clocks, clk, Qclk, /clk, /Qclk, as data transitions occur and are detected.
[0045] FIG. 10A is a subinterval transition diagram illustrating how adjacent data transition time subintervals in one direction (or the other) signify whether the frequency of the local multi-phase set of sampling clocks is too high, too low, or correct. For example, a transition from subinterval W to subinterval X provides an indication that the frequency of the multi-phase set of sampling clocks is too high, while the reverse order provides an indication that the frequency of the multi-phase set of sampling clocks is too low. According to one embodiment of the invention, adjacent data transition time subintervals are converted to frequency UP and frequency DOWN commands, according to the truth table shown in FIG. 10B . As explained below, these frequency UP and frequency DOWN commands can be used for frequency-error reduction purposes. It is important to note that this frequency correction process operates while the CDR is correctly operating on the incoming data stream. As such, the present clock frequency correction process is a background process. This is in direct opposition to the prior art, where frequency correction must be accomplished successfully before any CDR operation can begin.
[0046] FIG. 11 is a diagram of an instant-acquisition CDR circuit 1100 similar to the instant-acquisition CDR circuit shown in FIG. 4 , but which also includes frequency-error-reduction circuitry, according to an embodiment of the present invention. The frequency-error-reduction circuitry comprises a subinterval transition decoder 1102 that implements the truth table in FIG. 10B , a loop filter 1104 , and a multi-phase oscillator 1106 for generating the multi-phase set of clocks, clk, Qclk, /clk, /Qclk. The subinterval transition decoder 1102 generates frequency UP and frequency DOWN commands in response to the output of the data path and clock phase selector 406 and according to entries in the truth table in FIG. 10B . The loop filter 1104 , which may comprise a conventional PLL loop filter, responds to the frequency UP and frequency DOWN commands by changing the control signal applied to the multi-phase oscillator 1106 . In this manner, the frequency of the multi-phase set of sampling clocks, clk, Qclk, /clk, /Qclk, is corrected. Lock is achieved when the number of frequency UP commands received by the loop filter 1104 is, on average, equal to the number of frequency DOWN commands received by the loop filter 1104 . This frequency correction process is performed while the serial communications link is active and communicating actual data, thereby reducing “stress” on the clock and data recovery process. No training sequence or header information is needed in the frequency correction process.
[0047] The present invention has been described with reference to specific exemplary embodiments. These specific exemplary embodiments are merely illustrative, and are not meant to restrict the present invention. They are also not meant to be limited for use in any particular application. For example, the instant-acquisition CDR methods and systems of the present invention may be used in an LR in a communication link formed between a data communication device such as a computing device and a peripheral device, a computing device and a storage device (e.g., a hard drive), a baseband controller and the radio in a battery powered wireless communications device (e.g., a cellular handset), between clock domains of a digital system, or other serial communications link. Accordingly, the spirit and scope of the inventions defined in the appended claims should not be construed as being restricted to any particular application. | Methods and systems for recovering clock and data in data streams communicated over serial communications links. An exemplary serial communications receiver system includes a line receiver configured to receive a data stream from a serial communications link and an instant-acquisition clock and data recovery circuit coupled to the line receiver. The instant-acquisition clock and data recovery circuit includes a time interval detector and a sampling clock selector. The time interval detector is operable to sample the data stream received by the line receiver according to a multi-phase set of sampling clocks. The sampling clock selector is operable to designate one of the sampling clocks of the multi-phase set of sampling clocks as a recovered clock, based on a data transition in the received data stream detected by the time interval detector. The clock selector is configured to designate the sampling clock as the recovered clock independent of data transitions in the data stream that may have occurred prior to the data transition detected by the time interval detector. | 7 |
CROSS-REFERENCE TO RELATED APPLICATIONS
Priority of U.S. Provisional Patent Application Ser. No. 61/046,120, filed Apr. 18, 2008, incorporated herein by reference, is hereby claimed.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
Not applicable
REFERENCE TO A “MICROFICHE APPENDIX”
Not applicable
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to continuous batch washers or tunnel washers. More particularly, the present invention relates to an improved method of washing textiles or fabric articles (e.g. clothing, linen, etc.) in a continuous batch tunnel washer wherein the textiles are moved sequentially from one module or zone to the next module or zone including initial pre-wash zones, a plurality of main wash zones, a pre-rinse zone, and then transferred to an extractor that performs the final rinse and that removes water. More particularly, the present invention relates to an improved method of washing textiles in a continuous batch tunnel washer wherein a counter flow of wash liquor from one module or zone to the next module or zone is stopped, allowing for a standing bath. Chemicals are then added to separate soil from the goods and suspend the soil in the wash liquor. After a period of time, counter flow is commenced again to remove the suspended soil.
2. General Background of the Invention
Currently, washing in a commercial environment is conducted with a continuous batch tunnel washer. Such continuous batch tunnel washers are known (e.g. U.S. Pat. No. 5,454,237) and are commercially available (www.milnor.com). There are also machines that do not counterflow. Continuous batch washers have multiple sectors, zones, stages, or modules including pre-wash, wash, rinse and finishing zone. Commercial continuous batch washing machines utilize a constant counter flow of liquor and a centrifugal extractor or mechanical press for removing most of the liquor from the goods before the goods are dried.
Currently, a counter flow is used during the entire time that the fabric articles or textiles are in the main wash module zone. This practice dilutes the washing chemical and reduces its effectiveness. Additionally, while the bath liquor is being heated, this thermal energy is partially carried away by the counter flow thus wasting energy while a desired temperature value is achieved.
A final rinse with any continuous batch washer is sometimes performed using a centrifugal extractor or mechanical press. In prior art systems, if centrifugal extraction is used, it is typically necessary to rotate the extractor at a first low speed that is designed to remove soil laden water before a final extract.
Patents have issued that are directed to batch washers, tunnel washers, rinsing schemes and the like. The following table provides examples.
TABLE
PAT.
NO.
TITLE
ISSUE DATE
4,236,393
Continuous tunnel batch washer
Dec. 02, 1980
4,485,509
Continuous batch type washing
Dec. 04, 1984
machine and method for
operating same
4,522,046
Continuous batch laundry
Jun. 11, 1985
system
5,211,039
Continuous batch type washing
May 18, 1993
machine
5,454,237
Continuous batch type washing
Oct. 03, 1995
machine
BRIEF SUMMARY OF THE INVENTION
The present invention improves the current art by reducing water consumption, improving rinsing capability, reducing the number of components required to perform the function of laundering fabric articles or textiles, and saving valuable floor space in the laundry.
The present invention reduces and/or combines zones, sectors, or modules and improves the method of processing the textiles. Rinsing is done in two zones, first in the continuous batch washer itself in a pre-rinse zone after the main wash. A final rinse is then done in a mechanical water removal machine such as a centrifugal extractor or mechanical press.
When the goods are initially transferred into the main wash modules, the counter flow of wash liquor into the modules is stopped allowing for a standing bath. Chemicals are added to separate the soil from the goods and suspend the soil in the wash liquor. If needed, the wash liquor to the separate module bath is raised in temperature to facilitate the release of soil from the goods and activate the chemicals.
Once the soil has been released from the textiles, there is no more work for the chemicals to perform. At this time, the process can be described as chemical equilibrium. At this point, water by counter flow is commenced to remove the suspended soil. This could be termed an intermediate rinse since the water counter flowing into the module or zone is cleaner than what is counter flowing out of the module or zone. When the goods have progressed in this manner through the tunnel to a point where no more wash chemicals are needed, then the water flowing into the module or zone begins the rinsing process. This rinsing is termed pre-rinse. A final rinse can be performed in a centrifugal extractor or mechanical press.
The process of the present invention uses fresh water in the extractor that can be supplied through an atomizing nozzle while the goods are being extracted at high speed (e.g. between about 200-1,000 g's). Because the free soil has already been removed in the pre-rinse zone, the spray rinse while extracting will not re-deposit soil on the linen thereby reducing or eliminating graying of the goods. It is not necessary to centrifuge (and drain at a low speed) the free water before the final extract. With the present invention the process time is reduced. The amount of fresh water required compared with conventional processes is reduced.
The method of the present invention uses less water than in current art because the counter flow throughout the wash and rinse modules or zones is stopped for part of the cycle. The spray rinse in the centrifugal extractor or mechanical press is more effective than the current practice of draining the free water from the linen and then refilling.
The method of the present invention preserves the washing effectiveness of current counter flow washers to wash heavy soil classifications because the amount of soil dilution is the same even though there are less zones, stages, or modules. The present invention provides a higher effective rinsing provided by the spray rinse in the centrifugal extractor because of the pre-rinse in the tunnel washer.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
For a further understanding of the nature, objects, and advantages of the present invention, reference should be had to the following detailed description, read in conjunction with the following drawings, wherein like reference numerals denote like elements and wherein:
FIG. 1 is a schematic diagram showing the preferred embodiment of the apparatus of the present invention;
FIG. 2 is a schematic diagram showing the preferred embodiment of the apparatus of the present invention;
FIG. 3 is a schematic diagram showing the preferred embodiment of the apparatus of the present invention;
FIG. 4 is a schematic diagram of an alternate embodiment of the apparatus of the present invention;
FIG. 5 is a schematic diagram of the alternate embodiment of the apparatus of the present invention;
FIG. 6 is a partial perspective view of the alternate embodiment of the apparatus of the present invention;
FIG. 7 is a partial perspective view of the preferred embodiment of the apparatus of the present invention;
FIG. 8 is a fragmentary perspective view of the alternate embodiment of the apparatus of the present invention showing the starch dispensing nozzle tube;
FIG. 9 is a fragmentary perspective view of the alternate embodiment of the apparatus of the present invention showing the starch dispensing nozzle tube; and
FIG. 10 is a fragmentary perspective view of the alternate embodiment of the apparatus of the present invention showing the starch dispensing nozzle tube.
DETAILED DESCRIPTION OF THE INVENTION
FIGS. 1-3 show schematic diagrams of the textile washing apparatus of the present invention, designated generally by the numeral 10 . Textile washing apparatus 10 provides a tunnel washer 11 having an inlet end portion 12 and an outlet end portion 13 . Tunnel washer 11 provides a number of modules such as the modules 14 - 18 shown in FIG. 1 . These modules 14 - 18 can include a first module 14 and a second module 15 which can be pre-wash modules. The plurality of modules 14 - 18 can also include modules 16 , 17 and 18 which are main wash and pre-rinse modules.
The total number of modules 14 - 18 can be more or less than the five (5) shown in FIG. 1 . FIG. 2 shows an alternate arrangement that employs a tunnel washer 11 having eight (8) modules 14 - 18 and 35 - 37 . FIG. 3 shows an alternate arrangement that employs a tunnel washer 11 having ten (10) modules 14 - 18 and 35 - 39 . In FIG. 2 , the modules 14 , 15 can be pre-wash modules. In FIG. 3 , modules 14 , 15 , 16 can be pre-wash modules. In FIG. 2 , the modules 16 , 17 , 18 and 35 , 36 , 37 can be main wash and pre-rinse modules. In FIG. 3 , the modules 17 , 18 and 35 , 36 , 37 , 38 , 39 can be main wash and pre-rinse modules. Instead of a two (2) or three (3) module pre-wash section (see FIGS. 1 , 2 , 3 ), a single module 14 could be provided as an alternate option for the pre-wash section.
Inlet end portion 12 can provide a hopper 19 that enables the intake of textiles or fabric articles to be washed. Such fabric articles, textiles, goods to be washed can include clothing, linens, towels, and the like. An extractor 20 is positioned next to the outlet end portion 13 of tunnel washer 11 . Flow lines 21 , 25 , 26 , 27 , 27 A are provided for adding water and/or chemicals to tunnel washer 11 at selected or desired locations.
When the fabric articles, goods, linens are initially transferred into the main wash modules 16 , 17 , 18 , a counter flow of wash liquor into these modules 16 , 17 , 18 is stopped allowing for a standing bath. In FIG. 1 , chemicals are then added as indicated by arrows 26 , 27 and 27 A to the modules 16 , 17 and/or 18 . In FIG. 2 , chemicals are added as indicated by arrows 26 , 27 , 27 A to the modules 16 , 17 , 18 , 35 , 36 and/or 37 . In FIG. 3 , chemicals are added to the modules 16 - 18 and 35 - 39 as indicated by the arrows 26 , 27 , 27 A. In each arrangement of FIGS. 1-3 , these chemicals separate the soil from the goods, linens or textiles and suspend the soil in the wash liquor. During this step of the method of the present invention, the wash liquor temperature can be elevated if needed to facilitate the release of soil from the goods, fabric articles or linens and activate the chemicals.
Once the maximum soil has been released from the textiles or fabric articles in each module, there is no more work for those chemicals to perform. At this time, the process can be described as chemical equilibrium. The flow of water is stopped for a time period sufficient to release soil from the goods such as for example between about twenty (20) seconds and one hundred twenty (120) seconds. However, this time interval can be between about ten (10) and three hundred (300) seconds.
After this time interval of having no counter flow, water by counter flow is commenced to remove the suspended soil. If more wash chemicals are to be added, then this counter flow can be termed intermediate rinse. Once the goods reach the module or zone where no more wash chemicals are added, then the counter flow can be termed pre-rinse. A final rinse is then performed in a centrifugal extractor or mechanical press 20 . The process of the present invention uses fresh water in the extractor that can be supplied via flow line 29 through an atomizing nozzle, for example while the goods are being extracted at high speed (e.g. between about 200 and 1,000 g's) using the extractor 20 .
Flow line 21 transmits water to hopper 19 as indicated by arrow 22 . Flow line 21 also carries water to pre-wash module 15 as indicated by arrow 23 . Arrow 24 indicates a flow of water from module 14 to module 15 as part of the pre-wash.
In FIG. 1 , flow line 25 adds water for counter flow pre-rinse to module 18 . Such water added via flow line 25 to module 18 flows in counter flow fashion from module 18 to module 17 to module 16 (see arrow 25 A). Arrows 26 and 27 indicate chemical addition to modules 16 and 17 respectively. Chemicals to be added to modules 16 and 17 and can include detergent, alkali and/or oxidizing agents as examples.
In FIG. 2 , flow line 25 adds water for counter flow pre-rinse to module 37 . Such water added via flow line 25 to module 37 flows in counter flow fashion from module 37 to module 36 , then 35 , then 18 , then to module 17 (see arrow 25 B in FIG. 2 ).
In FIG. 3 , flow line 25 adds water for counter flow pre-rinse to module 38 . Such water added via flow line 25 to module 38 flows in counter flow fashion from module 38 to module 37 , module 36 , module 35 , module 18 , and module 17 (see arrow 25 C).
In FIG. 1 , textiles or fabric articles that are pre-washed, washed, and then pre-rinsed in tunnel washer 11 are transferred from module 18 to extractor 20 as indicated schematically by arrow 28 . In FIG. 2 , the textiles or fabric articles that are pre-washed, washed, and then pre-rinsed in tunnel washer 11 are transferred from module 37 to extractor 20 as indicated schematically by arrow 28 . In FIG. 3 , textiles or fabric articles that are pre-washed, washed, and then pre-rinsed in tunnel washer 11 are transferred from module 39 to extractor 20 as indicated schematically by arrow 28 .
The method of the present invention thus conducts rinsing in two zones. Rinsing is first conducted in the tunnel washer 11 in a pre-rinse zone which occurs after the main wash. In FIG. 1 , pre-wash zones can be 14 , 15 . The pre-rinse zone and main wash zone can be modules 16 , 17 , 18 . In FIG. 2 , the pre-wash zone can be modules 14 and 15 while the main wash and pre-rinse zones can be modules 16 , 17 , 18 , 35 , 36 and 37 . In FIG. 3 , the pre-wash zone can be modules 14 , 15 and 16 while the main wash and pre-rinse zones can be modules 17 , 18 , 35 , 36 , 37 , 38 and 39 . The second rinse zone is the final rinse, which is conducted in the extractor 20 or other mechanical water removal machine such as a mechanical press.
Because the free soil has already been removed in the pre-rinse zone at modules 16 , 17 , 18 of FIG. 1 (or 16 - 18 , 35 - 37 of FIG. 2 or 16 - 18 , 35 - 39 of FIG. 3 ) as part of the method of the present invention, the spray rinse while extracting at high speed (between about 200-1,000 g's) will not redeposit soil on the linen thereby reducing or eliminating graying of the goods. With the present invention it is not necessary to centrifuge (and drain at a low speed) the free water before the final extract at 20 . With the present invention, the process time is thus reduced. The amount of fresh water required compared with conventional processes is reduced. The spray rinse and the centrifugal extractor 20 or mechanical press is more effective than the current practice of draining the free water from the linen and then refilling the extractor 20 .
An additional benefit of the pre-rinse concept of the present invention is to permit the mechanical press or extractor to have more time extracting the free water. This result follows because the effect of the pre-rinse is to remove most of the suspended soil. The amount of fresh water required for final rinse is thus greatly reduced. The time for rinsing is reduced, allowing this saved cycle time for water removal.
The method of the present invention preserves the washing effectiveness of current counter flow washers 11 to wash heavy soil classifications because the amount of soil dilution is the same even though there are fewer zones or stages or modules.
The present invention provides a higher effective rinsing provided by the spray rinse (arrow 30 ). Water is supplied by tank 43 . Spray water flows via flow line 29 and is sprayed via a nozzle at 30 into the centrifugal extractor 20 . A higher effective rinsing is provided because of the intermediate and pre-rinse that is conducted in the modules 16 , 17 , 18 as discussed above in FIG. 1 , and the additional modules as discussed above for FIGS. 2 and 3 .
Outlet valves 33 can be provided on each module 14 - 18 , 35 - 39 for each FIGS. 1 , 2 , 3 enabling any of the modules 14 - 18 or 35 - 39 to be drained as indicated by arrows 34 . Extracted water 31 can be added to water flow line 21 . Extracted water 31 can be supplemented with fresh water via flow line 32 .
FIGS. 4-10 show an alternate embodiment of the apparatus of the present invention, designated generally by the numeral 40 . The textile washing apparatus 40 of the alternate embodiment can provide the same tunnel washer 11 of the preferred embodiment having the modules 14 - 18 , 35 - 39 provided in any one of the embodiments of FIG. 1 , 2 or 3 . FIG. 4 shows the embodiment of FIG. 1 having a specially configured starch spray arrangement.
In FIG. 4 , a starch tank 41 contains starch that is to be injected into the linen, fabric articles, or clothing contained in extractor 20 . Starch for the table linen, clothing, fabric articles is pumped in the first phase of the cycle through a spray nozzle 60 (see FIGS. 8-10 ). Controlled flow metering can be achieved for example using an inverter controlled flow metering device. The precise amount of starch is thus injected into the linen, fabric articles, clothing or the like while in extractor 20 . Excess starch can be removed in a separate tank indicated as starch recovery tank 52 in FIG. 4 . Flow line 53 enables recovered starch in tank 52 to be transferred to starch tank 41 .
Starch tank 41 contains starch that is to be pumped via flow line 42 to nozzle 60 and then to extractor 20 . Fresh water tank 43 can also be used to pipe fresh water to extractor 20 , flowing through valve 45 to nozzle 60 . Valves 44 , 45 and 46 are provided for controlling the flow of either starch or fresh water or a combination thereof to nozzle 60 as shown in FIG. 4 .
Flow line 49 is a flow line that carries extracted water to tank 51 as it is purged from the fabric articles, clothing or linens contained in extractor 20 . Starch can be recovered via flow lines 49 , 50 to starch recovery tank 52 . Valves 44 , 47 are provided for valving the flow of starch from tank 41 to extractor 20 via flow line 42 . Valve 48 enables tank 41 to be emptied for cleaning or adding new starch.
In FIGS. 8-10 , starch spray nozzle 60 is shown in more detail. The spray nozzle 60 can provide an elongated section of conduit or pipe 61 . Spray nozzle 60 has an influent end 62 and a discharge end portion 63 . Conduit 61 provides an open ended bore 64 for conveying starch from flow line 42 to nozzle 60 . Influent end 62 provides a connection 80 for attaching conduit 61 to flow line 42 .
FIGS. 5-7 illustrate the spray pattern 76 that strikes the wall of drum 57 of extractor 20 as emitted by nozzle 60 . In FIGS. 6 and 7 , extractor 20 provides a drum 57 that provides a chamber 55 having an inlet 56 . Clothes, textiles, linens to be sprayed are discharged from tunnel washer 11 via chute 79 into the chamber 55 of extractor 20 . The extractor 20 is preferably movable between a loading and discharging position. The loading position is shown in FIGS. 5 and 6 . In the loading position, clothes transfer from the tunnel washer 11 to the chamber 55 via chute 79 . Pumps 54 can be used to aid in the transfer of water from tank 43 or starch from tank 41 into chamber 55 via nozzle 60 . The spray nozzle 60 produces a spray pattern 76 that extends substantially across the cylindrical wall 58 of drum 57 as shown in FIGS. 6 and 7 . Drum 57 thus provides an inlet 56 for enabling clothing, textiles, or other fabric articles to be added to the drum 57 interior 55 and a rear circular wall 59 . Notice in FIGS. 6 and 7 that the spray pattern 76 extends generally from inlet 56 to circular wall 59 , thus extending substantially across cylindric wall 58 as shown in FIGS. 6 and 7 . Arrow 77 in FIG. 7 illustrates the width of spray pattern 76 which can be about 16 degrees as an example along cylindrical drum wall 58 .
A mounting plate 65 can be provided having one or more openings 66 for attaching (for example, bolting) spray nozzle 60 to extractor 20 or to a frame that supports extractor 20 .
The discharge end portion 63 of spray nozzle 60 provides a nozzle tip 67 . The nozzle tip 67 provides a nozzle outlet 70 formed by side plates 71 , 72 , upper plate 73 and lower plate 74 . Atomizing water nozzle 68 , 69 are provided next to nozzle outlet 70 . The atomizing water nozzle 68 is mounted to upper plate 73 . The atomizing water nozzle 69 is mounted to lower plate 74 as shown in FIGS. 8-10 . Spray nozzle 60 can be equipped with aerating or atomizing nozzles 68 , 69 to control the consistency of the starch in the nozzle 60 , thus preventing starch build-up which might eventually plug of the nozzle 60 .
As part of the method of the present invention, all starch flow lines 42 , 60 can be purged with hot water from fresh water tank via flow line 75 .
The following is a list of parts and materials suitable for use in the present invention.
PARTS LIST
Part Number
Description
10
textile washing apparatus
11
tunnel washer
12
inlet end portion
13
outlet end portion
14
module
15
module
16
module
17
module
18
module
19
hopper
20
extractor
21
flow line
22
arrow
23
arrow
24
arrow
25
flow line
25A
arrow
25B
arrow
25C
arrow
26
arrow - chemical addition
27
arrow - chemical addition
27A
arrow - chemical addition
28
arrow - textile transfer
29
spray rinse flow line
30
arrow
31
extracted water
32
flow line
33
outlet valve
34
arrow
35
module
36
module
37
module
38
module
39
module
40
textile washing apparatus
41
starch tank
42
flow line
43
fresh water tank
44
valve
45
valve
46
valve
47
valve
48
valve
49
flow line
50
flow line
51
extracted water tank
52
starch recovery tank
53
flow line
54
pump
55
chamber
56
inlet
57
drum
58
cylindrical drum wall
59
circular drum wall
60
spray nozzle
61
conduit
62
influent end
63
discharge end
64
bore
65
mounting plate
66
opening
67
nozzle tip
68
atomizing water nozzle
69
atomizing water nozzle
70
nozzle outlet
71
side plate
72
side plate
73
upper plate
74
lower plate
75
flow line
76
spray pattern
77
arrow
78
drum moving mechanism
79
chute
80
connection
All measurements disclosed herein are at standard temperature and pressure, at sea level on Earth, unless indicated otherwise. All materials used or intended to be used in a human being are biocompatible, unless indicated otherwise.
The foregoing embodiments are presented by way of example only; the scope of the present invention is to be limited only by the following claims. | A method of washing fabric articles in a tunnel washer includes moving the fabric articles from the intake of the washer to the discharge of the washer through first and second sectors that are a pre-wash zone. In the pre-wash zone, liquid is counter flowed in the wash interior along a flow path that is generally opposite the direction of travel of the fabric articles. The fabric articles are transferred to a main wash zone, and a washing chemical is added to the main wash zone. At about the same time, counter flow is reduced or stopped. The main wash zone can be heated as an option. After a period of time (for example, between about 20 and 120 seconds) counter flow is increased. The increased counter flow after chemical treatment amounts to either an intermediate rinse or a pre-rinse depending upon which module or zone the goods occupy. The pre-rinse ensures that the fabric articles are substantially free of soil or the majority of any soil when they are transferred to an extractor for final removal of excess water. | 3 |
BACKGROUND OF THE INVENTION
This invention relates to protective devices and in particular to a protective device for instruments mounted on an instrument panel. More specifically, but without restriction to the particular use which is shown and described, this invention relates to a protective cover and lock means for the cover for protecting the radio and navigational instruments mounted on the instrument panel of an aircraft against theft.
Most privately owned light aircraft are provided with navigational instruments and radio equipment that are mounted for easy installation or removal for repair or replacement from the front of an instrument panel mounted within the airplane cockpit. Furthermore, most light aircraft are provided with cable operated controls including ailerons and elevators connected to a control column extending from the instrument panel which is turned by a wheel or a yoke. The elevators during flight are positioned by pushing foward or pulling back the control column in its longitudinal direction, and the ailerons are positioned by rotating the wheel.
Often such aircraft are not hangared, but merely tied down outside in a remote location on an airfield when not in use. When tied down in this manner, many small aircraft are provided with a control lock or lock pin under or near the instrument panel that drops through the control column to lock it into position to prevent control surface movements and resultant damage thereto due to wind. Such small aircraft are not usually so constructed that the instrment panel thereof is contained within an enclosure or cockpit which can be locked against the entry therein of unauthorized persons. Accordingly, the removal and theft of radio and navigational equipment and instrumentation, and also of the control lock and the aircraft itself, has become a matter of major concern to the owners of such small aircraft.
A number of devices have been patented which are directed toward overcoming the problems briefly outlined above. The problem of aircraft theft has been addressed by U.S. Pat. No. 3,898,823, issued to Russel S. Ludeman, Aug. 12, 1975 which discloses a device for locking the controls of an aircraft that includes brackets secured to the pedals and control column wheel interconnected by a tubular housing enclosing a piston like spring device which resiliently locks the wheel and control column against movement when parked, so as to prevent authorized flight of the aircraft. It does not, however, offer any means to cover and prevent theft of the instruments from the instrument panel.
The problem of instrumentation theft has been addressed by U.S. Pat. No. 3,699,787, issued to Ronald F. Corrado, Oct. 24, 1972 which discloses a hollow cover which is mounted over a control column and directly in front of the instrument panel. The cover is locked in place by a tumbler lock which cooperates with a locking device fixed in the instrument panel. While this patent offers protection against theft of the instruments, the practice thereof necessitates the drilling of holes in the instrument panel for the insertion of the locking device. Furthermore, it does not prevent a thief from manipulating the control shaft and connected control wheel to fly the plane away.
Both the aforementioned problems have been addressed by U.S. Pat. No. 4,228,974, issued to August B. Yates, Oct. 21, 1980 which discloses a cover plate mounted immediately adjacent the instrument panel by means of upper and lower clamping blocks secured about the control column in such a manner as to prevent unauthorized movements of the column and access to the instruments on the panel. While such devices have proven successful in the past, the rigid clamps holding the protective panel to the control column causes serious damage thereto should an unauthorized person attempt to pry the protective panel away from the instrument panel.
The foregoing illustrates limitations of the known prior art. Thus, it is apparent that it would be advantageous to provide an alternative to the prior art.
SUMMARY OF THE INVENTION
In one aspect of the present invention this is accomplished by providing a protective device for instruments mounted on an instrument panel having at least one control column extending therefrom, the protective device including a protective cover having at least one open ended aperture formed in the edge thereof for receiving the control column, a shroud connected to the protective cover along the periphery of the open ended aperture for covering a portion of the control column, a bar supported by the shroud so that the shroud and the bar extend about the control column, and means for locking the bar to the shroud in a manner such that no damage will be imparted to the control column in the event the cover is tampered with.
The foregoing and other aspects will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings. It is to be expressly understood however, that the drawings are not intended as a definition of the invention but are for the purpose of illustration only.
BRIEF DESCRIPTION OF THE DRAWINGS
In the drawings:
FIG. 1 is a front elevational view of a protective device constructed in accordance with the present invention and illustrated as installed in an aircraft cockpit;
FIG. 2 is a front elevational view illustrated uninstalled and showing alternate means for lockingly mounting the device on an instrument panel;
FIG. 3 is a side elevational view of the protective device of FIG. 2;
FIG. 4 is a top plan view of the protective device of FIGS. 2 and 3;
FIG. 5 is a side elevational view of the installed protective device of FIG. 1 enlarged to better illustrate the elements thereof;
FIG. 6 is a partial front elevational view of the installed protective device of FIG. 5;
FIG. 7 is an enlarged partial front elevational view of the installed protective device of FIG. 1 illustrating a lock anti-tamper guard secured to the protective device; and
FIG. 8 is a top plan view of the lock anti-tamper device of FIG. 7.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to FIG. 1 of the drawings, an instrument panel protective device constructed in accordance with the teachings of the present invention is designated generally by the numeral 10 and is illustrated installed over an instrument panel 12 in the front of the cockpit of a typical light aircraft. The illustrated cockpit is one for a two place light aircraft having the usual command pilot and copilot instrumentation 14, various control switches 16, and control columns 18, 21 extending from the instrument panel and movable longitudinally forward and backward to operate the elevators and rotatable to the right or to the left by the control wheels 22, 24 respectively to operate the ailerons. A control lock 26 is provided to prevent movement of the various aircraft control surfaces due to wind while the aircraft is parked and includes a lock pin 28 which is inserted through one of the control columns and its associated sheath (not shown) while the aircraft is parked on the ground.
The protective device 10 includes a generally elongate, rectangular protective cover or plate 30 formed of a rigid, lightweight material, for example aluminum, and positioned immediately adjacent the instrument panel 14 which has the basic shape such as illustrated in FIG. 1, but which, in certain instances, may be specifically designed for application to the particular type of instrument panel to which it is to be applied. The protective device further includes means 32 for lockingly mounting the protective cover in a position immediately adjacent the instrument panel. As shown in FIG. 1, and illustrated more clearly in FIGS. 2-4, the locking means includes a pair of open ended apertures 34, 36 formed in the bottom edge 38 of the protective cover 30 which are appropriately spaced to receive the control columns of the aircraft. A pair of shrouds 40, 42 are connected to the protective cover along the peripheries of the open ended apertures 34, 36 respectively and extend outwardly therefrom for covering a portion of each of the control columns.
As illustrated more clearly in FIGS. 2-4, each of the shrouds 40, 42 is of a generally inverted U-shaped configuration and includes a pair of generally vertically extending, spaced apart sidewalls 40a, 40b/42a,42b respectively. The spaced apart walls of each shroud each contain a plurality of successive oppositely disposed and aligned slots 44a, 44b, 44c and 44d, spaced progressively outwardly from the protective cover 30. Each successive slot is positioned progressively horizontally outwardly and vertically upwardly with respect to an inwardly adjacent slot so that the protective device of the present invention may advantageously be fitted into the cockpit of aircraft having control columns of varying diameters.
Referring again to FIG. 1, the protective device 10 of the present invention is secured to each of the control columns 18, 20 by means of a pair of bars 46, 48 which are removably supported by any selective oppositely aligned pair of slots formed in the wall of the shrouds 40, 42 respectively. Each of the bars has an aperture or through bore 50, 52 extending therethrough respectively for receiving a shackle 54, 56 of a respective padlock 58, 60. With the bars locked in the shrouds, each associated shroud and bar cooperate with one another to extend about each control column and lock the protective device thereto, thus preventing access to the instruments mounted on the instrument panel. However, it should be noted that while the protective cover is locked to the steering columns, it is not rigidly clamped thereto so that in the event of unauthorized tampering with the cover, the clearance between the shroud, the bars, and the control columns is such that damage to the control columns will not necessarily result.
Referring to FIG. 2, alternate means for lockingly mounting the protective cover immediately adjacent the instrument panel is illustrated in the form of a single bar 62 which is removably supported by both shrouds 40, 42. A pair of apertures 64, 66 are formed in the bar for receiving the shackles 54, 56 of the padlocks 68, 60 respectively and are spaced apart in a manner such that when the bar is installed in the shroud, each of the locks is positioned within a respective one of the shrouds. In the embodiment shown, the apertures are arranged so as to be positioned offset to one side of the center of the shroud immediately adjacent one of the shroud sidewalls to make tampering with the padlocks and removal thereof more difficult.
Referring now to FIGS. 5 and 6, the control lock 26 for preventing movement of the control column 18 and the controls associated therewith is illustrated in greater detail. The protective device 10 further includes an elongate rod 68 having an eye 70 formed at one end 72 thereof and received over the elongate lock pin portion 28 of the control lock. The other end 74 of the rod is positioned intermediate the shroud 40 and the control column 18 so that when the protective cover 30 is locked in position on the column the control lock 26 may not be removed.
Referring now to FIGS. 7 and 8 one of the padlocks 58 is illustrated with a anti-tamper guard generally designated by the numeral 76 installed thereon. The guard includes a generally rectangularly shaped block 78 having a slot 80 formed therein for receiving the shackle 54 of the padlock. The anti-tamper guard further includes a pair of spaced apart walls 82, 84 extending generally upwardly from a top surface of the block. Each of the walls is positioned generally parellel to and on opposite sides of the slot and includes a transversely extending slot 86, 88 respectively formed therein for receiving the bar 46. With the anti-tamper guard secured in position on the lock, the shackle thereof is rendered relatively inaccessible so that the lock may not be removed by unauthorized personel by means of a saw, bolt cutters and the like.
As illustrated in phantom in FIGS. 1 and 2, one or more optional cover plates 90, 92, 94 may be secured to the bottom edge 38 of the protective cover 30 in any desired preselected location to protect any instruments which may be mounted on the instrument panel in a position below the bottom edge of the protective cover. Moreover, means for providing access to the controls of certain instruments for repair or testing purposes may also be optionally included in the protective device. In the embodiment of FIG. 1, by way of example, the access means is in the form of a recess 96 formed in the bottom edge of the protective cover; however, it is to be understood that the access means may be selectively positioned at any desired location in the protective cover depending upon the particular instrumentation arrangement of the aircraft.
While the present invention has been described with reference to several preferred embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for the elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or materials to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the appended claims. | A device for protecting the navigational instruments and radio equipment mounted on an instrument panel in the cockpit of an aircraft against theft. The device includes a protective cover mounted immediately adjacent the instrument panel and means for locking the potective cover to the control column of the aircraft in a manner such that the aircraft controls will not be damaged in the event that the protective cover is tampered with. | 8 |
CROSS REFERENCE TO RELATED APPLICATION
This application is a U.S. National of International Application PCT/DE2010/001107, filed on Sep. 22, 2010, which claims priority to DE 102009042447.4, filed on Sep. 23, 2009, the disclosures of which are incorporated herein by reference for all purposes.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to a composition for producing coatings containing dialkyl ethers as an additive and it relates to the use of such compositions in coatings as well as coatings produced in this way.
2. Description of Prior Art
It is known that additives are used to improve the properties of paints and varnishes. A wide variety of substances, for example, waxes, are known and used as additives. Waxy varnish additives may be introduced in the form of wax-coated solid particles, which often act as delustering agents.
DE 1006100 B (corresponds to U.S. Pat. No. 2,838,413) discloses the production of a delustering agent of silicic acid hydrogels, which are dried, activated at elevated temperatures and impregnated with a petroleum wax of the chain length C50 to C60 with a low acid number, iodine number and saponification number as well as with a melting point above 80° C.
U.S. Pat. No. 3,816,154 describes the use of wax-coated silica gels as delustering agents in varnishes. The wax is applied to the silica gel particles either as a melt coating or as an emulsion coating. If the silica gel is coated with waxes and fatty acids at the same time, a better dispersibility and better light scatter properties are found. The additive composition is milled in a jet mill to a particle size of 2 μm to 10 μm, wherein the wax is a petroleum or polyolefin wax and the fatty acid used has a chain length of C12 to C18.
US 2001/0006993 discloses a dry-mixed additive consisting of one or more film-forming polymeric components and one or more carrier components based on alumina, aluminum hydroxide, wax-coated silica gel or a combination thereof. This additive is being promoted as a gloss-reducing agent.
EP 1095111 describes a powder varnish composition in which a wax-coated silicon dioxide in finely divided form is added as an additive by a dry mixing method wherein it may also contain aluminum oxide and aluminum hydroxide. The waxes used are natural animal wax (for example, beeswax and lanolin) or natural vegetable waxes (for example, carnauba wax), petroleum waxes (for example, paraffin wax, microcrystalline wax) or synthetic waxes (for example, polyethylene, polyol ether esters). In addition, long-chain esters and hydrocarbons may be used.
U.S. Pat. No. 5,356,971 discloses that synthetic or natural wax added to powder coatings creates better lubricant properties and water repellency. No negative effect on the weather resistance is observed. The melting point of the wax should be in the range of 50° C. to 280° C. and ideally is 10° C. to 20° C. below the processing temperature. The group of waxes comprises natural animal, vegetable and petroleum waxes or mineral waxes as well as long-chain esters. If pure wax is used, it has a negative effect on the adhesion of the powder coating to metal at higher wax contents (for example, >10 wt %). If a supported wax is used, the scratch resistance suffers a negative effect of more than 15% even at load levels of more than 15%.
SUMMARY OF THE INVENTION
In one aspect of the present invention provides an additive, which yields improved properties of the paint and/or varnish in various paint and varnish systems.
It has surprisingly been found that these additives in paints and varnishes with long chain dialkyl ethers lead to a higher flexibility, greater chemical resistance and scratch resistance of the hardened coating compositions.
BRIEF DESCRIPTION OF THE DRAWINGS
The single FIGURE shows a comparison of flexibility and abrasion resistance and the improvement using the present invention.
DESCRIPTION OF PREFERRED EMBODIMENTS
The dialkyl ethers and/or dialkyl ether mixtures have 24 or more carbon atoms, in particular 32 to 44 carbon atoms. The dialkyl ethers and/or dialkyl ether mixtures are solid at room temperature (25° C.). These are preferably symmetrical dialkyl ethers. Long-chain saturated and unsaturated dialkyl ethers are suitable, for example, but are not limited to this list: didodecyl ether, ditetradecyl ether, dihexadecyl ether, dioctadecyl ether, dieicosyl ether, didocosyl ether, ditetracosyl ether, dihexacosyl ether, dioctacosyl ether, ditriacontyl ether, didotriacontyl ether as well as mixtures thereof.
By adding the inventive additives consisting of long-chain dialkyl ethers to paints and varnishes, in particular to powder coatings, the flexibility and chemical resistance as well as the scratch resistance can be increased.
The dialkyl ethers are preferably used as solid particles, in particular with average particle sizes (D 50 ) of less than 150 μm, in particular less than 60 μm. According to one embodiment, the dialkyl ether is added in micronized form (average particle diameter, for example, D 50 <60 μm, preferably D 50 <15 μm) to the coating composition, such as a paint or a varnish. In another embodiment, it is applied to an inorganic carrier material (for example, D 50 <150 μm, preferably D 50 <30 μm) and in yet another embodiment, it is added to the formulation prior to homogenization. The particle size and/or the average particle diameter D 50 is determined using a Malvern Mastersizer 2000 in accordance with ISO 13320-1, with the results being analyzed according to the Fraunhofer theory.
Inorganic compounds may be used as the carrier materials. Special effects are achieved, depending on the material and the surface properties. Suitable materials include silica, silica gels, aluminas and alumina hydrates. In this context, products of a high specific surface area (for example, >140 m 2 /g, measured by means of BET from N 2 according to DIN ISO 9277) have proven to be especially suitable. These products can be coated with the dialkyl ethers with no problem with loads up to 70 wt %, based on the sum of the carrier and the dialkyl ether, without any loss of pourability. If products of a lower specific surface area are used, a lower dialkyl ether load must be used. Maximum loads of 35 wt % have proven practical for a surface area of <50 m 2 /g, maximum loads of 50 wt % at 50-140 m 2 /g and up to 70 wt % at >140 m 2 /g.
Varnishes in the sense of the present invention may be differentiated according to aqueous varnish systems containing a solvent and those that are free of solvent. Solvent-based varnishes are further differentiated into systems that are film-forming systems at ambient temperature and baked-on enamels that can dry physically or chemically.
All solvent-based varnishes contain pigments, fillers, binders, solvents and other additives. Solvents may include (but are not limited to), for example, hydrocarbons such as benzines, naphtha, xylene, toluene, alcohols such as methanol, ethanol, propanol, butanol, pentanol, hexanol, esters such as ethyl acetate, butyl acetate, ethers such as dipropyl ether, dibutyl ether, dipentyl ether, dihexyl ether, diheptyl ether, dioctyl ether, dinonyl ether, didecyl ether, ethyl glycol, butyl glycol or butyl diglycol. Pigments may be of an organic and/or inorganic type.
Additional additives suitable in the sense of the present invention include, for example, heavy metal salts of carboxylic acids as siccatives for oxidatively curing systems, anti-skinning agents such as ketoxime, UV absorbers, plasticizers such as the esters of phthalic acid, adipic acid, trimellitic acid, sebacic acid, citric acid, phosphoric acid, benzoic acid or fatty acids with alcohols, hydrocarbons, chlorinated paraffins or epoxidized fatty acid esters or oils, flow agents or dispersant aids.
For example, systems which are film-forming at ambient temperatures by physical drying may contain binders such as cellulose nitrate, other cellulose esters, polyvinyl halides and copolymers thereof, polyvinyl esters, polystyrene, hydrocarbon resins, rubber derivatives, high-polymer epoxy resins, polyamides, polycarbonates and polyacrylate resins.
In systems which dry chemically according to the present invention, the binders are oxidized by the action of atmospheric oxygen, for example, as in polyunsaturated oils, alkyd resins or epoxy resin esters. Another possibility for chemically drying systems includes, for example, two-component systems such as two-component polyurethane varnishes, where the binder dries by reaction of isocyanate groups with alcohol groups. Alcohol groups may be present, for example, in saturated polyesters, alkyd resins, acrylate resins, polyethers, epoxy resins and epoxy esters, PVC copolymers or polyvinylacetals.
Baked-on enamels form films only at temperatures between 80° C. and 250° C. Binders may be constructed of at least two reactive components such as amino resins as well as self-crosslinking building blocks.
Basic building blocks here form amides such as urea, carbonate, melamine, benzoguanamine or glycoluril and formaldehyde. Amino resins may also be reacted with binders containing hydroxyl groups such as alkyd resins, saturated polyesters, hydroxy-functional acrylate resins, epoxy resins, epoxy resin esters and polyvinyl resins. Another possibility is phenolic resins obtained by reaction of phenols with formaldehyde. Baked-on enamels based on capped polyisocyanates, acrylate resins, polyesters or polysiloxanes are also known.
The solvent-based varnish systems can be differentiated according to “low solids” (<30%), “normal solids” (30-60%), “medium solids” (60-70%) and “high solids” (>70%), depending on the nonvolatile component.
In contrast with the solvent-based varnish systems, aqueous varnish systems contain water as the main solvent. In addition, co-solvents such as ethanol, propanol, isopropanol or butanol may also be used. Polymer dispersions, for example, acrylic dispersions, styrene dispersions, acrylate dispersions, vinyl acetate-ethylene copolymer dispersions in water, water-dilutable alkyd resins and/or epoxy resins may be used as binders here.
Further additives in aqueous varnish systems may include rheology additives such as polymers or inorganic phyllosilicates, dispersants such as polyacrylates or polyphosphates, foam suppressants, for example, based on hydrocarbons or silicones, preservatives, film-forming aids, pH stabilizers or anti-corrosion additives. Like solvent-based baked-on enamels, these are also available as aqueous systems.
Solvent-free varnish systems may be either chemically reactive systems, for example, two-component polyurethane varnishes in which either a liquid polyol reacts with a liquid polyisocyanate, or a liquid blocked isocyanate group-terminated prepolymer reacts with a liquid polyamine, two-component epoxy resins, two-component unsaturated polyesters, for example, linear, soluble polycondensates of unsaturated and partially saturated dicarboxylic acids, for example, maleic acid anhydride or fumaric acid and polyvalent alcohols, such as ethylene glycol, 1,3-propanediol, diethylene glycol or neopentyl glycol.
Another possibility for curing the products is UV-induced drying, wherein a radical crosslinking reaction is triggered by UV light. Binders for UV enamels include, for example, unsaturated polyesters, acrylates, for example, epoxy acrylates, polyester acrylates, polyether acrylates, polyurethane acrylates and saturated acrylate resins or silicone acrylates.
No solvent is used in powder coatings, which cure in the melt. A low melt viscosity is desired. The powder usually has an average grain size of 18 μm to 80 μm. Binders used for thermoplastic powder coatings include polyethylene, polyvinyl chloride, polyamides, ethylene-vinyl-alcohol copolymers and saturated polyesters; binders used for crosslinking powder coatings include epoxy resins, epoxy resins/polyesters, hybrid systems, polyurethane polyester systems or acrylate resins.
Other suitable varnish systems and their exemplary compositions are described, for example, in the textbook “Varnish Formulation and Varnish Recipes” by Bodo Müller and Ulrich Poth, published by Vincentz Verlag. This textbook is herewith also incorporated into the disclosure content of the present invention.
The invention is explained by the following example:
The paint additive was prepared by joint milling of the dialkyl ethers and the inorganic carrier to form particles.
Example 1
Preparing an Additive Based on Silicic Acid
50 g dioctadecyl ether (NACOL® Ether 18 from Sasol, Germany GmbH) was weighed into a batch mill together with 50 g of a silica (for example, Aerosil® 300 from Evonik) and milled for five minutes. The product was thermally regulated for one hour at 80° C.
Example 2
Producing an Additive Based on Alumina
50 g dioctadecyl ether (NACOL® Ether 18 from Sasol, Germany GmbH) was weighed in a batch mill together with 50 g of an alumina (Puralox® UF5/230 from Sasol, Germany GmbH) and milled for five minutes. The product was thermally regulated at 80° C. for one hour.
In the following examples the dialkyl ether was applied by heat impregnation of the inorganic carrier.
Example 3
Producing an Additive Based on Silica
50 g dioctadecyl ether (NACOL® Ether 18 from Sasol, Germany GmbH) mixed with 50 g of a silica (for example, Aerosil® 300 from Evonik). After cooling, the solids were milled for five minutes in a batch mill.
Example 4
Producing an Additive Based on Alumina
50 g dioctadecyl ether (NACOL® Ether 18 from Sasol, Germany GmbH) was mixed with 50 g of a alumina (for example, Disperal® HP 14□ from Sasol, Germany GmbH). After cooling, the solids were milled for five minutes in a batch mill.
According to another embodiment, the organic coverage of polysilicic acid or alumina hydrate was added before drying.
Example 5
Producing an Additive Based on Silica
50 g dioctadecyl ether (NACOL® Ether 18 from Sasol, Germany GmbH) was melted and combined with 50 g dry solids of a freshly prepared polysilicic acid. The product was dried at 120° C. and then ground to the desired grain size.
Example 6
Producing an Additive Based on Alumina
50 g dioctadecyl ether (NACOL® Ether 18 from Sasol, Germany GmbH) was melted and combined with 50 g dry solids of a freshly prepared alumina hydrate. The product was dried at 120° C. and then ground to the desired grain size.
Another possibility is to use the dialkyl ether(s) directly in solid form, for example, as a powder or pastilles.
The following raw materials were used in the following examples:
TABLE I
Raw Materials
Brand name
Chemical name
Manufacturer
Crelan ® EF 403
cycloaliphatic polyuretdione
Bayer
(MW = 310 g/mol)
Rucote ® XP 2566
polyester (OH number 38)
Bayer
Rucote ® 109
polyester containing hydroxyl
Bayer
groups (OH number 265)
Resiflow ® PV 88
acrylate flow control agent
Worlée
based on silicate
The additives produced in this way were used in powder coatings. This will now be illustrated on the following examples:
TABLE II
with Examples 7 through 9
Example No.
Additive
7
Example 2
8
Example 4
9
Dioctadecyl ether
160.9 g Crelan® EF 403, 224.8 g Rucote® XP 2566, 96.1 g Rucote® 109, 6.0 g Resiflow® PV 88, 2.5 g benzoin, 5 g Gas Black FW 200 and 5 g of the additive were homogenized for five minutes in a mixer at 10,000 rpm. Next the mixture was extruded in a twin-screw extruder at temperatures of 100° C. (zone 1) and 110° C. (zone 2) at a shaft speed of 200 rpm, product temperature 110° C. to 115° C., a rotational speed of the feed screw of 15 rpm and a rotational rate of the cooling roller of 40 rpm. The powder coating extrudate was pulverized and then milled finely in a screen-bottom mill at 10,000 rpm. Coarse-grain fractions larger than 120 μm in size were removed using a vibrating screen, and the powder was electrostatically applied to plate steel using a corona gun at 70 kV. The coating was baked for ten minutes at 200° C.
TABLE III
with example 10 through 14:
Example No.
Additive
10
Example 1
11
Example 2
12
Example 3
13
dioctadecyl ether
14
dibehenyl ether
157.5 g Crelan® EF 403, 220 g Rucote® XP 2566, 94 g Rucote® 109, 6.0 g Resiflow® PV 88, 2.5 g benzoin, 4.9 g Gas Black FW 200 and 15 g of the additive were homogenized for five minutes in a mixer at 10,000 rpm. The mixture was next extruded in a twin-screw extruder at temperatures of 100° C. (zone 1) and 110° C. (zone 2) at a shaft rotational speed of 200 rpm, product temperature 110-115° C., a rotational speed of the feed screw of 15 rpm and a rotational speed of the cooling roller of 40 rpm. The powder coating extrudates were pulverized and then ground finely at 10,000 rpm in a screen-bottom mill. Coarse-grain fractions greater than 120 μm in size were removed with a vibrating screen and the powder was applied electrostatically to a steel plate using a corona gun at 70 kV. The coated plates were based for ten minutes at 200° C.
Comparative Example 1
160.9 g Crelan® EF 403, 224.8 g Rucote® XP 2566, 96.1 g Rucote® 109, 6.0 g Resiflow® PV 88, 2.5 g benzoin, 5 g Gas Black FW 200 and 5 g of a micronized PE wax (from BYK) was homogenized for five minutes at 10,000 rpm in a mixer. The mixture was next extruded in a twin-screw extruder at temperatures of 100° C. (zone 1) and 110° C. (zone 2) at a shaft rotational speed of 200 rpm, a product temperature 110-115° C., a rotational speed of the feed screw of 15 rpm and a rotational speed of the cooling roller of 40 rpm. The powder coating extrudates were pulverized and then ground finely in a screen-bottom mill at 10,000 rpm. Coarse-grain fractions more than 120 μm in size were removed using a vibrating screen and the powder was applied to a steel plate electrostatically at 70 kV using a corona gun. The coated plates were baked for ten minutes at 200° C.
Comparative Example 2
160.9 g Crelan® EF 403, 224.8 g Rucote® XP 2566, 96.1 g Rucote® 109, 6.0 g Resiflow® PV 88, 2.5 g benzoin, 5 g Gas Black FW 200 and 5 g of a powdered synthetic polymer (Ceraflour® 967, from BYK) were homogenized for five minutes at 10,000 rpm in a mixer. Next the mixture was extruded in a twin-screw extruder at temperatures of 100° C. (zone 1) and 110° C. (zone 2) at a shaft rotational speed of 200 rpm, product temperature 110-115° C., a rotational speed of the feed screw of 15 rpm and a rotational speed of the cooling roller of 40 rpm. The powder coating extrudates were pulverized and then ground finely in a screen-bottom mill at 10,000 rpm.
Coarse-grain fractions more than 120 μm in size were removed using a vibrating screen and the powder was applied electrostatically to a steel plate at 70 kV using a corona gun. The coated plates were baked for ten minutes at 200° C.
Comparative Example 3
157.5 g Crelan® EF 403, 220 g Rucote® XP 2566, 94 g Rucote® 109, 6.0 g Resiflow® PV 88, 2.5 g benzoin, 4.9 g Gas Black FW 200 and 15 g of a micronized PE wax (from BYK) were homogenized for five minutes in a mixer at 10,000 rpm. The mixture was next extruded in a twin-screw extruder at temperatures of 100° C. (zone 1) and 110° C. (zone 2) at a shaft rotational speed of 200 rpm, product temperature 110-115° C., a rotational speed of the feed screw of 15 rpm and a rotational speed of 40 rpm of the cooling roller. The powder coating extrudates were pulverized and then ground finely in a screen-bottom mill at 10,000 rpm. Coarse-grain fractions more than 120 μm in size were removed using a vibrating screen, the powder being electrostatically applied to steel plate using a corona gun at 70 kV. The coated plates were baked for ten minutes at 200° C.
Comparative Example 4
157.5 g Crelan® EF 403, 220 g Rucote® XP 2566, 94 g Rucote® 109, 6.0 g Resiflow® PV 88, 2.5 g benzoin, 4.9 g Gas Black FW 200 and 15 g of a powdered synthetic polymer (Ceraflour® 967, from BYK) were homogenized for five minutes at 10,000 rpm in a mixer. Next the mixture was extruded in a twin-screw extruder at temperatures of 100° C. (zone 1) and 110° C. (zone 2) at a shaft rotational speed of 200 rpm, product temperature 110-115° C., a rotational speed of the feed screw of 15 rpm and a cooling roll rotational speed of 40 rpm. Powder coating extrudates were pulverized and then ground finely in a screen-bottom mill at 10,000 rpm. Coarse-grain fractions larger than 120 μm in size were removed using a vibrating screen and the powder was electrostatically applied steel plates using a corona gun at 70 kV. The coated plates were baked for ten minutes at 200° C.
The resulting powder coatings were tested to determine their reactivity, their flexibility, their resistance to chemicals, their abrasion resistance, their resistance to yellowing and their gloss.
The analyses that were performed are summarized briefly below:
Reactivity
The reactivity of a system was determined according to the gelation time. A marked increase in viscosity was observed due to the formation of the polymer network. The time of this change in property was determined using a shearing disc viscometer at 200° C.
Flexibility
The flexibility of the coating system was determined with the help of the Erichsen indentation according to DIN EN 50101. The plate coated with the powder coating was held on the die by a hold-down force and a hardened ball was pressed against the plate from beneath, thereby inducing a cold deformation. The distance traveled until a crack developed was recorded.
Resistance to Chemicals
The coated plates were provided with acetone and covered with sheets of glass. The solvent was allowed to act overnight. The next day the acetone resistance was evaluated visually, using the following scale:
TABLE IV Surface Acetone Resistance Grade Explanation 0 no change in surface 1 very slight change in surface 2 slight change in surface 3 change in surface 4 great change in surface 5 complete change in surface
Abrasion Resistance
To test the abrasion resistance, the surface was treated with 10 double strokes of sandpaper weighted with 500 g, and then the gloss of the scratched surfaces was evaluated. The residual gloss in % was used as a measure of the abrasion resistance.
Colorimetry
The color values were measured using a convention color value meter (X-Rite Color Eye 7000a) as the difference in comparison with a standard. The results are given in lab format. The Lab color space is a measurement space comprising all perceptible colors and is independent of the device. The color measurement is performed according to DIN 6174.
Gloss
The gloss was measured using a BYK haze-gloss meter according to DIN EN ISO 2813.
TABLE IV
flexibility, resistance to chemicals and residual gloss after abrasion
Example
Resistance to
Residual gloss
Example
indentation (mm)
chemicals
after abrasion
7
8.5
3
86.5
8
7.0
3
90.8
9
6.5
3
69.3
Comparative 1
6.0
3
68.8
Comparative 2
2.7
3
34.8
10
8.3
2
68.3
11
6.5
1
73.5
12
8.3
2
68.3
13
7.2
1
72.3
14
7.9
1
74.5
Comparative 3
5.8
3
63.7
Comparative 4
7.8
2
33.0
A negative effect on the reactivity or colorimetry not found in any of the examples.
The goal was in particular to produce an additive having at least 50% residual gloss and an Erichsen indentation of at least 6.5 mm. Comparative Examples 2 and 4 fail to achieve the minimum criterion of abrasion resistance, expressed by a residual gloss of more than 50%. Although Comparative Examples 1 and 3 yield adequate abrasion resistance, they do not meet the minimum requirements for flexibility of the coating.
The products from the examples solve the stated problem of achieving an improved abrasion resistance and flexibility as demonstrated in FIG. 1 .
By using dialkyl ethers with and without carriers, the properties with respect to flexibility, resistance to chemicals and abrasion resistance of the powder coating can be improved significantly without having any effect on the reactivity or colorimetry. | The invention relates to compositions for producing coatings containing dialkylether as an additive, said type of coatings and to the use of dialkylethers in coatings, in particular a novel paint and lacquer additive based on dialkylether as a component of said compositions, said additive improving the resistance to abrasion, chemical resistance and mechanical properties to the lacquer system without changing the color metrics and reactivity. | 2 |
TECHNICAL FIELD
The present invention relates to non-psychoactive derivatives of tetrahydro-cannabinol, which exhibit anti-inflammatory, analgesic and leukocyte anti-adhesion activities. The invention includes novel derivatives of (3R,4R)-Δ 8 -tetrahydrocannabinol-11-oic acids [hereinafter referred to as (3R,4R)-Δ 8 -THC-11-oic acid], as well as pharmaceutical compositions containing the (3R,4R)-Δ 8 -THC-11-oic acid derivatives. The invention further includes methods of administering the novel derivatives and pharmaceutical compositions as therapeutic agents in the treatment of pain, tissue inflammation, leukocyte anti-adhesion activity, and the like.
BACKGROUND OF THE INVENTION
Δ 9 -Tetrahydrocannabinol [THC], depicted in Formula I under alternate numbering systems, is the major psychoactive constituent of marijuana. ##STR1## In addition to mood-altering effects, THC has been reported to exhibit other activities, some of which may have therapeutic value. The potential therapeutic value of THC has led to a search for related compounds which, while devoid of psychoactive effects, retain the activities of potential medicinal value.
Previous work with Δ 8 -Tetrahydrocannabinol [(3R,4R) 6a,7,10,10a-tetrahydro-6,6,9-trimethyl-3-pentyl-6H-dibenzo[b,d]pyran-1-ol, hereinafter referred to as Δ 8 -THC], which is depicted in Formula II below, has indicated that certain derivatives of this compound depicted in Formula II below, may prove clinically useful. The 11-carboxy derivative of Δ 8 -THC [Δ 8 -THC-11-oic acid] has been reported to be a non-psychoactive, potent antagonist to endogenous platelet activating factor and, thus, a useful treatment for PAF-induced disorders, such as asthma, systemic anaphylaxis, and septic shock. (U.S. Pat. No. 4,973,603, issued to the present inventor). Another derivative, (3S,4S)-11-hydroxy-Δ 8 -THC-1',1' dimethylheptyl essentially free of the (3R,4R) form, has been reported to possess analgesic and anti-emetic activities. (U.S. Pat. No. 4,876,276).
U.S. Pat. No. 4,847,290, issued to the present inventor, discloses a method of relieving pain in mammals by administering an effective analgesic amount of Δ 9 -THC-11-oic acid or an analog thereof. These THC derivatives are disclosed to be non-psychoactive metabolites.
U.S. Pat. No. 5,338,753, also issued to the present inventor, discloses (3R,4R)-Δ 8 -Tetrahydrocannabinol-11-oic acid derivatives having Formula II below: ##STR2## wherein R 1 is a hydrogen atom, --COCH 3 or --COCH 2 CH 3 ; R 2 is a straight chain or branched C 5 -C 12 alkyl, which may have a terminal aromatic ring; a group --(CH 2 ) m --O--R 3 , wherein m is an integer from 0 to 7 and R 3 is a straight chain or branched alkyl group containing from 1 to 12 carbon atoms, which may have a terminal aromatic ring; or a group CH--(CH 3 )--(CH 2 ) n --O--R 4 , wherein n is an integer from 0 to 7 and R 4 is a straight chain or branched alkyl containing from 1 to 12 carbon atoms, which may have a terminal aromatic ring. These Δ 8 -THC-11-oic acid derivatives are also discussed in an article by Sumner H. Burstein, et al., entitled "Synthetic Nonpsychotropic Cannabinoids with Potent Antiinflammatory, Analgesic, and Leukocyte Antiadhesion Activities." [J. Medicinal Chem., 35(17):3135-3136 (1992).
It is desired, however, to obtain compounds, pharmaceutical compositions, and methods of treatment using compounds substantially devoid of psychoactive effect and with improved therapeutic effects compared to those achieved by conventional Δ 8 -THC-11-oic acid derivatives, such as those described above. The present invention advantageously affords such compounds, pharmaceutical compositions, and methods of treatment using the compounds and compositions.
SUMMARY OF THE INVENTION
The present invention relates to a compound having the formula: ##STR3## wherein R 1 is hydrogen, --COCH 3 , or --COCH 2 CH 3 ; R 2 is a branched C 5-12 alkyl compound which may have a terminal aromatic ring, or a branched --OCHCH 3 (CH 2 ) m alkyl compound which may have a terminal aromatic ring, wherein m is 0 to 7; R 3 is hydrogen, a C 1-8 alkyl compound, or a C 1-8 alkanol compound; and Y is nil or a bridging group of NH or oxygen; provided that where Y is oxygen and R 2 is a branched C 5-12 alkyl compound, R 3 is not --CHCH 3 .
In one preferred embodiment, R 1 is hydrogen, R 2 is 1',1'-dimethylheptyl, and Y is nil. In another preferred embodiment, R 2 is a branched --O(CHCH 3 )(CH 2 ) m alkyl compound terminated with a phenyl ring, wherein m is 0 to 7, and R 3 is --CHCH 3 . This embodiment includes the stereoisomers of such compounds, as well as a racemic mixture or any other percentage mixture of the stereoisomers between 0 and 100 weight percent.
The invention also relates to pharmaceutical compositions that include the compound and its two preferred embodiments described above.
The invention further relates to methods of relieving pain in a mammal by administering to the mammal a therapeutically effective analgesic amount of the compound or pharmaceutical composition, or either of the preferred embodiments, described above.
The invention also relates to methods of relieving inflammation of bodily tissue of a mammal by administering to the mammal a therapeutically effective anti-inflammatory amount of the compound or pharmaceutical composition, or either of the preferred embodiments, described above.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates a synthetic scheme for the preparation of the Δ 8 -THC-11-oic acid derivatives according to the present invention.
FIG. 2 illustrates an alternative synthetic scheme for the preparation of the Δ 8 -THC-11-oic acid derivatives according to the present invention.
DETAILED DESCRIPTION OF THE INVENTION
The present invention relates to (3R,4R)-Δ 8 -Tetrahydrocannabinol-11-oic acid derivatives depicted in Formula III below: ##STR4## wherein R 1 is hydrogen, --COCH 3 , or --COCH 2 CH 3 ; R 2 is a branched C 5-12 alkyl compound which may have a terminal aromatic ring, or a branched --OCHCH 3 (CH 2 ) m alkyl compound which may have a terminal aromatic ring, wherein m is 0 to 7; R 3 is hydrogen, a C 1-8 alkyl compound, or a C 1-8 alkanol compound; and Y is nil or a bridging group of NH or oxygen; provided that where Y is oxygen and R 2 is a branched C 5-12 alkyl compound, R 3 is not --CHCH 3 .
Preferred compounds are obtained when R 1 is hydrogen, R 2 is 1',1'-dimethylheptyl, and Y is nil. Thus, in this preferred form, the compounds have Formula IV below: ##STR5## In these compounds, R includes hydrogen, branched or unbranched C 1-8 alkyl compounds, and branched or unbranched C 1-8 alkanol compounds. In a more preferred form, R is methyl or methanol, or a branched or unbranched ethyl, propyl, ethanol, or propanol.
Preferred compounds are also obtained when R 2 is a branched --OCHCH 3 (CH 2 ) m alkyl compound terminated with a phenyl ring, wherein m is 0 to 7, Y is NH or oxygen, and R 3 is --CHCH 3 . More preferred compounds include those where m is 3, and these compounds have Formula V below: ##STR6## In the preferred compounds, R 1 is hydrogen, --COCH 3 , or --COCH 2 CH 3 , and more preferably R 1 is hydrogen.
The preferred and more preferred compounds are also similarly preferred when used in pharmaceutical compositions and for methods of eliciting an analgesic effect and treating tissue inflammation and leukocyte anti-adhesion activity by administration of a compound or pharmaceutical composition according to the invention.
The phrase "therapeutically effective amount," "therapeutically effective analgesic amount," or "therapeutically effective anti-inflammatory amount" means that amount of the pharmaceutical composition that provides a therapeutic benefit in the treatment, prevention, or management of pain, tissue inflammation, and leukocyte anti-adhesion activity.
The compositions of the present invention can be used in both veterinary medicine and human therapy. The magnitude of a prophylactic or therapeutic dose of the composition in the acute or chronic management of pain, tissue inflammation or leukocyte anti-adhesion activity will vary with the severity of the condition to be treated and the route of administration. The dose, and perhaps the dose frequency, will also vary according to the age, body weight, and response of the individual patient. In general, the total daily dose range of the active ingredient of this invention is generally between about 10 and 500 mg per 70 kg of body weight per day, preferably between about 50 and 250 mg per 70 kg of body weight per day, and more preferably between about 100 and 150 mg per 70 kg of body weight per day. The actual preferred amounts of the active ingredient will vary with each case, according to the species of mammal, the nature and severity of affliction being treated, and the method of administration. In general, the compositions of the present invention are periodically administered to an individual patient as necessary to improve symptoms of the disease being treated. The length of time during which the compositions are administered and the total dosage will necessarily vary with each case, according to the nature and severity of the affliction being treated and the physical condition of the subject.
Generally, then, each daily dose is a unit dose, i.e., tablet, cachet or capsule, which contains between about 10 mg to 700 mg of the active ingredient, or pharmaceutical composition, preferably about 50 mg to 250 mg, and more preferably about 100 mg to 150 mg of the active ingredient (i.e., excluding excipients and carriers). If desired, the daily dose may include two or more unit doses, i.e., tablets, cachets or capsules, to be administered each day.
It is further recommended that children, patients aged over 65 years, and those with impaired renal or hepatic function initially receive low doses, and that they then be titrated based on individual response(s) or blood level(s). It may be necessary to use dosages outside these ranges in some cases, as will be apparent to those of ordinary skill in the art. Further, it is noted that the clinician or treating physician will know how and when to interrupt, adjust, or terminate therapy in conjunction with individual patient response.
The term "unit dose" is meant to describe a single dose, although a unit dose may be divided, if desired. Although any suitable route of administration may be employed for providing the patient with an effective dosage of the composition according to the methods of the present invention, oral administration is preferred. Suitable routes include, for example, oral, rectal, parenteral (e.g., in saline solution), intravenous, topical, transdermal, subcutaneous, intramuscular, by inhalation, and like forms of administration may be employed. Suitable dosage forms include tablets, troches, dispersions, suspensions, solutions, capsules, patches, suppositories, and the like, although oral dosage forms are preferred.
The pharmaceutical compositions used in the methods of the present invention include the active ingredients described above, and may also contain pharmaceutically acceptable carriers, excipients and the like, and optionally, other therapeutic ingredients. In one embodiment, for example, the drug is dissolved in a vegetable oil, such as olive oil or peanut oil, and, optionally, encapsulated in a gelatin capsule. For human therapy, a preferred method of administering compounds or pharmaceutical compositions having Formula III, IV, or V is orally, in the form of a gelatin capsule.
The term "pharmaceutically acceptable salt" refers to a salt prepared from pharmaceutically acceptable non-toxic acids or bases including inorganic or organic acids. Examples of such inorganic acids are hydrochloric, hydrobromic, hydroiodic, sulfuric, and phosphoric. Appropriate organic acids may be selected, for example, from aliphatic, aromatic, carboxylic and sulfonic classes of organic acids, examples of which are formic, acetic, propionic, succinic, glycolic, glucuronic, maleic, furoic, glutamic, benzoic, anthranilic, salicylic, phenylacetic, mandelic, embonic (pamoic), methanesulfonic, ethanesulfonic, pantothenic, benzenesulfonic, stearic, sulfanilic, algenic, and galacturonic. Examples of such inorganic bases, for potential salt formation with the sulfate or phosphate compounds of the invention, include metallic salts made from aluminum, calcium, lithium, magnesium, potassium, sodium, and zinc. Appropriate organic bases may be selected, for example, from N,N-dibenzylethylenediamine, chloroprocaine, choline, diethanolamine, ethylenediamine, meglumaine (N-methylglucamine), and procaine.
The compositions for use in the methods of the present invention include compositions such as suspensions, solutions and elixirs; aerosols; or carriers such as starches, sugars, microcrystalline cellulose, diluents, granulating agents, lubricants, binders, disintegrating agents, and the like, in the case of oral solid preparations (such as powders, capsules, and tablets), with the oral solid preparations being preferred over the oral liquid preparations. The most preferred oral solid preparations are capsules.
Because of their ease of administration, tablets and capsules represent the most advantageous oral dosage unit form, in which case solid pharmaceutical carriers are employed. If desired, tablets may be coated by standard aqueous or nonaqueous techniques.
In addition to the common dosage forms set out above, the compound for use in the methods of the present invention may also be administered by controlled release means and/or delivery devices such as those described in U.S. Pat. Nos. 3,845,770; 3,916,899; 3,536,809; 3,598,123; and 4,008,719, the disclosures of which are hereby incorporated by reference.
Pharmaceutical compositions for use in the methods of the present invention suitable for oral administration may be presented as discrete units such as capsules, cachets, or tablets, or aerosol sprays, each containing a predetermined amount of the active ingredient, as a powder or granules, as creams, pastes, gels, or ointments, or as a solution or a suspension in an aqueous liquid, a non-aqueous liquid, an oil-in-water emulsion, or a water-in-oil liquid emulsion. Such compositions may be prepared by any of the methods of pharmacy, but all methods include the step of bringing into association the carrier with the active ingredient which constitutes one or more necessary ingredients. In general, the compositions are prepared by uniformly and intimately admixing the active ingredient with liquid carriers or finely divided solid carriers or both, and then, if necessary, shaping the product into the desired presentation.
For example, a tablet may be prepared by compression or molding, optionally, with one or more accessory ingredients. Compressed tablets may be prepared by compressing in a suitable machine the active ingredient in a free-flowing form, such as powder or granules, optionally mixed with a binder (e.g., carboxymethylcellulose, gum arabic, gelatin), filler (e.g., lactose), adjuvant, flavoring agent, coloring agent, lubricant, inert diluent, coating material (e.g., wax or plasticizer), and a surface active or dispersing agent. Molded tablets may be made by molding, in a suitable machine, a mixture of the powdered compound moistened with an inert liquid diluent. Those skilled in the art will know, or will be able to ascertain with no more than routine experimentation, appropriate pharmacological carriers for said pharmaceutical compositions.
EXAMPLES
The invention is further defined by reference to the following examples describing in detail the preparation of the compound and the compositions used in the methods of the present invention, as well as their utility. The examples are representative, and they should not be construed to limit the scope of the invention.
Examples 1-2
Preparation of Derivatives
The compounds of Formula III may be prepared according to the synthetic schemes depicted in FIGS. 1 and 2. FIG. 1 depicts a scheme to produce compounds of Formula IV, and FIG. 2 depicts a scheme to produce compounds of Formula V. DMH is dimethylheptyl in the figures, where 1',1'-dimethylheptyl is used in the preparation of the compounds and compositions of the present invention. The intermediates and final compounds in these schemes are generally prepared by the methods disclosed in Schwartz, A., and Madan, P., J. Org. Chem., 51:5463-5465 (1986), which is expressly incorporated by reference thereto for the purpose of teaching a skilled artisan how to prepare the compounds of the present invention.
In general, melting points are taken in glass capillary tubes with a Thomas-Hoover Uni-Melt apparatus. Infrared spectra are recorded on a JASCO A-200 spectrophotometer. Rotations are determined on a Perkin-Elmer Model 141 polarimeter in chloroform. Chromatographic separations are performed on silica gel columns (Woelm TSC silica, for dry chromatography, activity III/30 mm, No. 04530). The high-resolution mass spectrometry (HRMS) is performed on a Varian 711 instrument.
1. Preparation of (trans-R,R & S,S)-6a,7,8,9,10,10a-Hexahydro-1,9dihydroxy-6aR-3-DMH-dibenzo[b,d]-pyran-9-carbonitrile--Step a,b
A solution of 5 g (0.016 mol) of the DMH-substituted compound shown at the top of FIG. 1 in 175 mL methanol is added to a suspension of 5 g (0.10 mol) of sodium cyanide in 20 mL of methanol, and the resulting mixture is stirred at room temperature under nitrogen for 2 hrs.
To this mixture is added 5.75 mL of glacial acetic acid in 50 mL of methanol, and stirring is continued for 0.5 hrs. The pH of the mixture is adjusted to about 2 with anhydrous HCl (g), and the mixture is stirred overnight under nitrogen, whereupon the solvent is removed by using a 40° C. water bath and an aspirator. The residue is dissolved into 75 mL of water and extracted with 2×100 mL of methylene chloride. The combined organic layers are dried (Na 2 SO 4 ) and the solvent is concentrated to dryness, first on a rotary evaporator at 40° C. (20 mm) and finally for 0.5 hrs. at 0.5 mm, to afford the a,b-product compound as a light yellow foam, used without further purification in the next step. An analytical sample is prepared by recrystallization from CH 2 Cl 2 /petroleum ether to give colorless needles.
2. Preparation of (trans-R,R & S,S)-6a,7,8,9,10,10a-Hexahydro-1,9-dihydroxy-6aR-3-DMH-dibenzo[b,d]-pyran-9-carboxylic acid methyl ester--Step d
Anhydrous HCl (g) is bubbled into a stirred solution of about 5.5 g of the a,b-product compound in 150 mL methanol at 3° C. (ice bath) over a period of 1.25 hrs. to saturation. The flask is capped with a septum and kept in the freezer (-20° C.) for 72 hrs.
To this mixture is added 75 mL of 6N aqueous HCl, and the solvent is concentrated to dryness, first on a rotary evaporator (35° C. at 20 mm) and finally at 0.5 mm to afford an oil that is suspended in 150 mL of 50% aqueous methanol. A copious white precipitate is formed on standing at room temperature overnight. The solids are collected by filtration and then dissolved in 250 mL of ethyl acetate. A small amount of water is separated and the organic layer dried (Na 2 SO 4 ) and concentrated to dryness in vacuo (30° C. at 20 mm).
The residue is triturated with 50 mL of petroleum ether (bp 30-60° C.). The solids are collected by filtration, washed with 50 mL of petroleum ether, and then dried in vacuo (0.5 mm) for 2 hrs. to afford 3.1 g of the compound as a colorless solid. The mother liquors are concentrated to give 1.3 g of a yellow oil, which, when analyzed, indicates the epimeric hydroxy ester of the d-product compound.
3. Preparation of (trans-R,R & S,S)-6a,7,10,10a-Tetrahydro-1-hydroxy-6aR-3-DMH-dibenzo[b,d]-pyran-9-carboxylic acid methyl ester--Step e
A 50 mL reaction flask equipped with a nitrogen bubbler and a magnetic stirrer are charged with 1.4 g of the above d-product compound, 10 mL of pyridine, and 2.0 mL of thionyl chloride, and then the reaction mixture is stirred at room temperature under nitrogen for 1 hr. This mixture is quenched by pouring into 30 mL of ice water and extracted into 3×30 mL of ethyl acetate. The organic layer is dried (Na 2 SO 4 ) and evaporated to dryness to afford about 1.2 g as a solidified foam. The foam is triturated with 30 mL of petroleum ether (30-60° C.) to afford 975 mg of the e-product compound as a light yellow solid.
4. Preparation of (trans-R,R & S,S)-6a,7,10,10a-Tetrahydro-6aR-3-DMH-dibenzo[b,d]-pyran-9-carboxylic acid--Step f
A solution of 50 mL of MeOH and 15 mL of 1 N NaOH is placed in a 100-mL three-necked flask equipped with magnetic stirrer and bubbler and heated to reflux while Ar gas is passed through the solution for 30 min. via a gas dispersion tube. The tube is removed, 540 mg of the e-product compound above is added in one portion to the refluxing solution, and the resultant mixture (now green) is allowed to reflux for 2 hrs, after which TLC analysis in silica (EtOAc-hexanes, 1:1) indicate complete reaction. The reaction mixture is cooled to 5° C. (ice bath) and acidified with methanolic HCl to pH 1. The solvent is removed under vacuum, and the residue is dissolved in 25 mL of water, extracted into CHCl 3 (3×100 mL), and dried over Na 2 SO 4 . The solvent is removed under vacuum to give an oil, to which 25 mL of hexanes is added, and the solution is kept in a refrigerator 10° C. overnight. The resultant crystals are filtered to give about 490 mg of the f-product compound.
Following subsequent catalysis with hydrogen, the above f-product compound becomes the presently claimed invention, wherein the R is the R 3 group, where Y is nil.
The scheme in FIG. 2 permits preparation of the presently claimed compounds by use of the above procedure. In this manner, compounds where Y is oxygen or NH; where R 3 equals R equals --CHCH 3 , and where R 2 is a branched --OCHCH 3 (CH 2 ) m alkyl compound which may have a terminal aromatic ring, wherein m is 0 to 7, may be prepared.
Example 3
Leukocyte Adhesion Test
Leukocytes are thought to be major contributors to the inflammatory response, and their ability, in this regard, is reflected by their adhesion to a variety of substrates. Following the procedure of Audette and Burstein (Audette, C. A., and Burstein, S., "Inhibition of Leukocyte Adhesion by the In Vivo and In Vitro Administration of Cannabinoids," Life Sci. 47:753-759 (1983), peritoneal cells from female CD-1 mice (20-25 g) are collected at ninety (90) minutes following oral administration of the test compound or vehicle (50 μL of peanut oil). Cells from each treatment group (N=3) are pooled, and equal numbers of cells are aliquoted into six culture dish wells (1.9 cm 2 area). After incubation for 18-20 hours, nonadhering cells are removed and the remaining cell monolayer quantitated by DNA measurement. Cell viability is monitored by Trypan Blue exclusion.
Example 4
Measurement of Cataleptic Effects
The cataleptic response in mice or other laboratory animals is measured using the ring test described by Pertwee. (Pertwee, R. G., "The Ring Test: A Quantitative Method of Assessing the Cataleptic Effect of Cannabis in Mice," Br. J. Pharmacol. 46:753-763 (1972)). Mice are placed on a horizontal wire ring 5.5 cm in diameter, which is attached to a 16 cm vertical rod. The hind paws and fore paws are placed at opposite sides of the ring. It is important that the ambient temperature be maintained at 30° C. and that the environment be free of auditory stimuli and bright lights. The response is calculated as the fraction of time the mouse is immobile over a five (5) minute test period. Measurements are done between a fixed time, e.g., 2 p.m. to 4 p.m.
Example 5
Paw Edema Test for Inflammation
The induction of paw edema, in rodents, by the injection of arachidonic acid, has been used as an experimental model for inflammation. (Calhoun W. et al. "Effect of Selected Antiinflammatory Agents and Other Drugs on Zymosan, Arachidonic Acid, PAF and Carrageenan Induced Paw Edema in the Mouse." Agents Actions 21:306-309 (1987)). Administration of non-steroidal anti-inflammatory drugs (NSAIDs) prior to induction with arachidonic acid, leads to a dose-related inhibition which may be considered predictive of clinical efficacy.
The conditions were as previously reported by Calhoun et al., and by Burstein et al. (Burstein S. et al. "Antagonism to the Actions of PAF by a Nonpsychoactive Cannabinoid." J. Pharmacol. Exper. Ther. 251:531-535 (1989)), with water being substituted for mercury as the displacement medium. PAF (1.0 μg) or arachidonic acid (1.0 mg) dissolved in 50 μL of 5% ethanol in saline, is injected subcutaneously into the plantar surface of the right hind paw of ether-anesthetized CD-1 female mice (20-25 g) obtained from Charles River Laboratories. The volume of the right foot is measured to the level of the lateral malleolus by water displacement before treatment, fifteen (15) minutes after PAF injection, or thirty (30) minutes after arachidonic acid injection. The change in paw volume is calculated for each mouse and the significance for each group is determined by a paired t test. The compounds of the present invention are then tested to determine efficacy in reducing arachidonate-induced paw edema.
Example 6
Hot Plate Test for Antinociception
The hot-plate test is a method for measuring the analgesic activity of pharmacologic agents based on the reaction time of mice to lick their forepaws and/or jump after being placed on an aluminum hot plate heated to, and maintained at, 54-56° C. (Kitchen I and Green PG. "Differential Effects of DFP Poisoning and Its Treatment on Opioid Antinociception in the Mouse." Life Sci. 33:669-14 672 (1983).
An aluminum surface is maintained at 55±1° C. by circulating water through the passages in the metal. A clear plastic cylinder, 18 cm in diameter and 26 cm high, is placed on the surface to prevent escape. The end point is taken when the mouse either performed a hind paw lick or jumped off the surface; in no case are the animals kept more than 30 seconds on the plate. Mice are never used more than one time; control values are measured at 11 a.m. and test values at 2 p.m. The compounds to be tested are administered orally ninety (90) minutes before the hot plate test. The percent change in response time (latency) is calculated by comparing the mean of the control values with the mean of the test values and statistical significance determined by a paired t test.
Example 7
Preparation of Capsules
A large number of unit capsules are prepared by filling standard two-piece hard gelatin capsules each with the desired amount of powdered active ingredient as described above, 150 milligrams of lactose, 50 milligrams of cellulose, and 6 milligrams magnesium stearate.
Example 8
Preparation of Soft Gelatin Capsules
A mixture of active ingredient in a digestible oil such as soybean oil, lecithin, cottonseed oil or olive oil is prepared and injected by means of a positive displacement pump into gelatin to form soft gelatin capsules containing the desired amount of the active ingredient. The capsules are washed and dried for packaging.
Examples 9-23
Various Compounds of the Invention
Various compounds of the present invention may be prepared, for example, according to Examples 1 and 2 above. The following table illustrates various specific embodiments of the compounds of Formula III of the present invention. When Y is nil, R equals R 3 in the table below.
______________________________________Example R.sub.1 R.sub.2 R.sub.3 Y______________________________________ 7 hydrogen DMH hydrogen nil 8 hydrogen DMH CH.sub.3 -- nil 9 hydrogen DMH CH.sub.3 CH.sub.2 -- nil10 hydrogen DMH CH.sub.3 CH.sub.2 CH.sub.2 -- nil11 hydrogen DMH --CH.sub.2 OH nil12 hydrogen DMH --(CH.sub.2).sub.2 OH nil13 hydrogen DMH --(CH.sub.2).sub.3 OH nil14 hydrogen DMH --(CH.sub.2).sub.4 OH nil15 hydrogen DMH --(CH.sub.2).sub.5 OH nil16 hydrogen --OCHCH.sub.3 --CHCH.sub.3 oxygen (CH.sub.2).sub.3 Ph17 --COCH.sub.3 --OCHCH.sub.3 --CHCH.sub.3 oxygen (CH.sub.2).sub.3 Ph18 --COCH.sub.2 CH.sub.3 --OCHCH.sub.3 --CHCH.sub.3 oxygen (CH.sub.2).sub.3 Ph19 hydrogen --OCHCH.sub.3 --CHCH.sub.3 NH (CH.sub.2).sub.3 Ph20 --COCH.sub.3 --OCHCH.sub.3 --CHCH.sub.3 NH (CH.sub.2).sub.3 Ph21 --COCH.sub.2 CH.sub.3 --OCHCH.sub.3 --CHCH.sub.3 NH (CH.sub.2).sub.3 Ph______________________________________ DMH = 1',1dimethylheptyl; Ph = Phenyl
Those skilled in the pharmaceutical art will recognize, or be able to ascertain using no more than routine experimentation, many equivalents to the specific embodiments of the invention described herein. Such equivalents are intended to be encompassed by the following claims. | The present invention relates to non-psychoactive derivatives of tetrahydro-cannabinol, which exhibit anti-inflammatory, analgesic and leukocyte antiadhesion activities. The invention includes novel derivatives of (3R,4R)-Δ 8 -tetrahydrocannabinol-11-oic acids [hereinafter referred to as (3R,4R)-Δ 8 -THC-11-oic acid], as well as pharmaceutical compositions containing the (3R,4R)-Δ 8 -THC-11-oic acid derivatives. The invention further covers methods of administering the novel derivatives and pharmaceutical compositions as therapeutic agents in the treatment of pain and tissue inflammation. Non-psychoactive derivatives of Δ 8 -THC-11-oic acid are described which have analgesic and anti-inflammatory properties. | 2 |
This application is a continuation of application Ser. No. 924,353, filed Oct. 29, 1986, now abandoned.
BACKGROUND OF THE INVENTION
The present invention relates to a device for sensing the level of a liquid within a container. More particularly, the present invention relates to a device able to detect the presence of lubricating oil of an engine within the interior of an associated reservoir such as, for example, the oil collection sump thereof.
Numerous level sensing devices are known in commerce, which provide an indication of electrical type when the level of the liquid under test falls below a minimum predetermined value. There are, for example, known sensors which utilize a pair of bimetal elements mounted at the end of a rod which is held immersed in the container; on one of these elements there is wound a resistor which is periodically supplied with electric current in such a way as to generate a localized heating of one of the two bimetal elements. Depending on whether or not these elements are immersed in the liquid, there will occur a dispersion of the heat developed in the mass of liquid or else a concentration of the heat on the bimetallic element. In the first case the bimetal element does not show any practical effects of the variation of heat and therefore does not deform, whereas in the second case the localized variation of temperature causes a deformation of the bimetal element and consequent opening of the electrical contact, is established by this latter. The disadvantages presented by devices of the above specified type are principally connected with the criticality of intervention and the cost of the devices themselves, which require for their operation a suitable electronic circuit to supply them.
There are likewise known sensor devices which essentially comprise a magnet supported by a tubular float, and a magnetically actuable electric contact element supported by a suitable element, which also performs the function of constituting the guide for displacements of the float under the action exerted by the hydrostatic thrust of the liquid. It is observed, however, that such devices are hardly used in the detection of the level of oil because the viscosity of this liquid creates a high surface tension between the float and the associated support element, making excursions of the first with respect to the second difficult and therefore involving a low precision or indication of the predetermined level.
SUMMARY OF THE INVENTION
The object of the present invention is that of providing a level sensor device for a liquid within a container, which allows the disadvantages presented by sensors of known type and specified above to be overcome.
This object is achieved with the present invention in that it relates to a sensor device for detecting the presence of a liquid at a predetermined level within the interior of a reservoir and of the type comprising at least one magnet supported by a tubular float, and a magnetically actuable electric contact element fixed to a suitable support element, this latter being introduceable into the said container to constitute a guide for displacements which the hydrostatic thrust exerted by the liquid induce in the float; the sensor device is characterized in that it includes centering means defining an essentially constant relative positioning of the float with respect to the guide and support element over the section traversed by the float under the action exerted by the hydrostatic thrust.
BRIEF DESCRIPTION OF THE DRAWINGS
For a better understanding of the present invention there is now described a preferred embodiment purely by way of non-limitative example, with reference to the attached drawings, in which :
FIG. 1 is a view in elevation and partially in section of a sensor device formed according to the principles of the present invention and illustrated in one example of application; and
FIGS. 2 and 3 are sections, along an enlarged scale, taken on the lines II--II and III--III of FIG. 1.
DETAILED DESCRIPTION OF THE INVENTION
With particular reference to FIG. 1, there is generally indicated with reference numeral 1, a sensor device for detecting the presence of a liquid 2 at a predetermined level 3 within a container 4 of which there is indicated a wall 5 which could be an upper wall or else a bottom wall of the container itself.
The device 1 essentially comprises a magnet 7, a tubular float 8 supporting the magnet 7, a magnetically actuable electrical contact element 9 and a support element 10 essentially constituted by a small tube within which is fixed the electrical contact element 9. In more detail, the contact element 9 has a first terminal 11 which partially projects, in an axial direction, from the support tube 10, the latter being conveniently formed of a metallic and non-magnetic material. The terminal 11 is fixed to an end portion 12, conveniently folded outwardly, of the tube 10 by means of a suitable soldering indicated 13. The electrical contact element 9 has a second terminal 15 which is soldered to a bare end portion of a conductor 16 which is normally covered with a protective sheath 17 and which defines with the sheath a cable 18 able to convey to the exterior an electrical indication relating to the opening and closure of the electrical contact element 9 in dependence on the position assumed by the magnet 7 under the hydrostatic thrust exerted by the liquid 2. The terminal 15 and the conductor 16 are covered in correspondence with their contact zones by means of an insulating covering 19 conveniently made with a material of heat resisting type to avoid any unwanted electrical contact between the terminal 15 or conductor 16 and the tube 10.
According to the present invention, the device 1 includes a pair of end caps 21, 22 which are fixed in correspondence with the opposite ends of the float 8 and have the purpose of centering and correctly spacing the float 8 from the tube 10 to avoid the possibility that surface tension exerted by the liquid 2 may cause the inner surface of the float 8 to adhere to the facing outer surface of the tube 10. For this purpose each end cap 21, 22 has, in correspondence with its annular base wall 23,24 radial tongues 25,26 (FIGS. 2 and 3), extending inwardly and cooperable with the facing surface of the tube 10 to maintain the float 8 spaced from the tube 10 itself. In particular the end cap 21 also serves the purpose of fixing the magnet 7 to the float 8 and has in particular an end portion 27 which is folded in towards the body of the float 8 in such a way as to constitute an attachment element. Conveniently, the end cap 21 is co-molded with the float 8. The end cap 22 can also be co-molded with the float 8, but preferably is simply secured by adhesive to the float not in fact having to support the magnet 7.
The device 1 further includes a body 30 having a threaded portion 31 which can be screwed into a corresponding threaded hole 32 in the wall 5 of the container 4. The body 30 further has a portion 33 of enlarged section which has, for example, hexagonal section which can be engaged by a corresponding key to allow screwing of the body 30; this portion 33 cooperates frontally with the outer surface of the wall 5 of the container 4 by means of an annular seal 34 to prevent the escape of liquid 2 from the hole 32. The body 30 has an axial through hole 36 passing therethrough, the diameter of which is essentially identical to the outer diameter of the tube 10. In effect tube 10 is slidably mounted within the hole 36 and there is, moreover, provided a bush 37 which serves to connect the body 30 and the tube 10 together. In particular, the bush 37 has a portion 38 of reduced section, which surrounds a terminal projection 39 of the body 30 and the tube 10. The fixing of the tube 10 to the projection 39 is obtained by squeezing the portion 38 of the bush 37 in such a way as to create a radial deformation both in the projection 39 a corresponding zone of the tube 10.The bush 37 further has, in the part facing the float 8, a ring 41 (formed integrally or soldered to the bush itself) the diameter of which is such that the contact between the ring 41 itself and the end cap 22 takes place only in correspondence with the tongues 26 of end cap 22, which, as is clearly visible in FIG. 2, are equi-distant and circumferentially distributed at 120°. In this way it is likewise avoided that the surface tension force causes an improper adhesion of the facing surfaces of the end cap 22 and the bush 37 and thus an unwanted retention of the float 8 to the bush 37 even when the level of liquid 2 falls below the level 3.
In use, the connection between the tube 10 and the body 30 occurs during a calibration operation. In substance, the tube 10 is displaced by making it slide within the hole 36 until it reaches a predetermined intervention height of the electrical contact element 9, conveniently detectable by means of a suitable tool. The calibration operation described above could also be effected with the float 8 immersed in the liquid 2, in which case it would also be necessary to take into account the constructional tolerances and positioning both of the float 8 and of the contact element 9. Once the correct position of the tube 10 with respect to the body 30 has been identified, and this could coincide with the actuation of the electrical contact 9, it is sufficient to perform the squeezing of the portion 38 of the bush 37 for the purpose of deforming radially both the projection 39 of the body 30 and the tube 10, thus fixing these with respect to one another.
The operation of the device 1 is essentially as known. In fact, once the device 1 has been introduced into the hole 32 in the container 4, the float 8 will act to carry the magnet 7 fixed to it in such a way as to allow actuation of an alarm signal (opening of the contacts of the element 9) when the level of the oil 2 falls below the predetermined level 3.
The electric signal generated by the device 1 is essentially a ground signal in that the terminal 15, fixed to the conductor 16, can be electrically connected to the terminal 11 through the contacts of the element 9; this terminal 11 then leads to ground generally via the soldering 25, the tube 10, the body 30 and the wall 5 of the container 4.
From a study of the characteristics of the device formed according to the present invention, the advantages which it allows to be obtained are evident. First of all the end caps 21 and 22 ensure a correct and constant spacing of the float 8 from the corresponding support tube 10 and therefore prevent the surface tension from making these latter adhere to one another and thereby influencing the relative travel of the float with respect to the tube 10. Further, the tongues 25 and 26 ensure that in the opposite working positions in which the float 8 rests on the outwardly facing end portion 12 of the tube 10 in correspondence with the soldering 13, or else against the surface of the ring 41 carried by the bush 37, there is no unwanted adhesion of the float 8 to the end portion 12 or to the ring 41, again which may otherwise arise because of surface tension, thus avoiding an incorrect positioning of the float itself.
Finally, it is observed that the possibility of adjusting within a wide range the relative position between the tube 10 and the body 30 makes it possible to utilize a single device for indicating the presence of the level of a liquid at different levels of the same container, or else of different containers, with obvious advantages from the point of view of the possible applications of the device itself.
Finally, it is clear that the device 1 described above can be modified and varied without departing from the scope of the present invention. For example, the tube 10 could be conveniently replaced by a bar of plastics material with the electrical contact element 9 co-molded within the interior. In this case the terminal 11 of the element 9 could be folded upwardly in such a way as to be connected with a further conductor of an electrical cable which, in the specific case would be bi-polar. The advantage of this solution would essentially lie in the fact that freedom would be gained from having to form a good electrical contact to ground at the terminal 11, an electrical contact which could be problematical to form if the container 4 were made of plastics material.
Numerous other variants of the adopted system of positioning the float 8 and the tube 10 could also be envisaged. For example, there could be provided indentations or axial ribs extending radially from the body of the tube 10, or else again there could conveniently be utilized an annular magnet having, on the part facing inwardly, radial guide indentations which would serve, in this case, the same function as the tongues 25. | The device is of the type comprising a magnet carried by a float and a magnetically actuable electric contact carried by a support element which also performs the function of guarding the float. The most important characteristic of the device is that of providing positioning means which maintain the float constantly centered with respect to the support element during excursions of this latter caused by the hydrostatic thrust exerted by the liquid. | 6 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a divisional of U.S. application Ser. No. 12/199,748, filed Aug. 27, 2008, which is hereby incorporated by reference in its entirety.
BACKGROUND
[0002] It is known that metal oxide such as titanium oxide may be used as photocatalyst by absorbing light energy. Using such effect, there have been attempts to remove environmental pollution such as the sources of air pollution and water pollution. In the past, it was general to use metal oxide by fixing it in a carrier such as metal, ceramic and activated carbon. However, in the case of fixing a photocatalyst on a surface, the photocatalyst can detach from the carrier. Also, it is not easy to change photocatalyst according to the shape of a reactor because the photocatalyst is fixed. In the case of using photocatalyst in a fixed carrier, it is not easy to replace photocatalyst whose activity is lowered because of aging and repetitive uses.
BRIEF DESCRIPTION OF THE DRAWINGS
[0003] FIG. 1 is a flow chart of an illustrative embodiment of a method for preparing a fiber.
[0004] FIG. 2 is a schematic diagram of an illustrative embodiment of a device having a fabric pad. 1 .
[0005] FIG. 3 is a schematic diagram of an illustrative embodiment of an apparatus using a fabric pad.
DETAILED DESCRIPTION
[0006] 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 in the detailed description, drawings, and claims 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 components 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.
[0007] In one embodiment, a method for preparing a fiber may include providing a solution containing at least one metal oxide precursor and/or at least one metal oxide to a carbon fiber, drying the carbon fiber to immobilize the metal oxide precursor and/or the metal oxide on a surface of the carbon fiber, providing a polycarbosilane melt to the carbon fiber, and heating the carbon fiber to obtain a fiber including silica and metal oxide. One such embodiment is shown in FIG. 1 .
[0008] In another embodiment, a fiber may include silica and metal oxide, where the fiber include a silica phase formed in a core of the fiber, and where the fiber includes a metal oxide phase formed on a surface of the fiber.
[0009] In yet another embodiment, an apparatus may include at least one fabric pad prepared from a fiber including silica and metal oxide, where the fiber includes a silica phase formed in a core of the fiber, and where the fiber include a metal oxide phase formed on a surface of the fiber, and at least one device for fixing the fabric pad.
A Method For Preparing A Fiber
[0010] In order to prepare a fiber including silica and metal oxide, a solution containing at least one metal oxide precursor and/or at least one metal oxide may be provided to a carbon fiber. A variety of suitable methods may be employed for providing a solution to the carbon fiber. In some embodiments, a solution may be coated on a surface of the carbon fiber using methods such as dip coating, spray coating and the like.
[0011] In one embodiment, a carbon fiber may include only carbon atoms. A carbon fiber may be prepared by pyrolyzing a fiber spun out of an organic precursor in the form of a fiber, under inert conditions. In one embodiment, the heating of the pyrolyzing process is carried out at a temperature of about 1000° C. to about 3000° C. A carbon fiber may include carbon of at a purity of about 92% to about 99.99%.
[0012] A carbon fiber may be classified into a cellulose carbon fiber (rayon carbon fiber), an acrylonitrile carbon fiber, a phenol carbon fiber, a pitch carbon fiber, a polyvinylalcohol carbon fiber and the like, according to a type of an organic precursor.
[0013] In one embodiment, a carbon fiber may be prepared from an appropriate organic precursor using standard methods. A structure of a carbon fiber may vary depending on a type of a precursor used, a method of heating the precursor, a temperature of the heating, and whether drawing is performed or not when heating. One skilled in the art may obtain a carbon fiber with desirable structure by properly modifying such conditions.
[0014] In one embodiment, an average diameter of the carbon fibers ranges from about 1 mm or less. In other embodiments, the carbon fiber diameter ranges from about 500 pm or less. In still other embodiments, the carbon fiber diameter ranges from about 100 μm or less. In yet other embodiments, the carbon fiber diameter ranges from about 50 μm or less, or even about 1 μm or less in still further embodiments. Further, in some embodiments a specific surface area of a carbon fiber may range from about 200 m 2 /g to about 3000 m 2 /g. In other embodiments the carbon fiber may have different specific surface area.
[0015] A carbon fiber may be in the form of one-dimensional filament or yarn. A carbon fiber may be manufactured in a desirable form. For example, in some embodiments, carbon fiber may be in the form of a fiber bundle, bulky fiber, woven fabric, non-woven fabric, braided fabric, paper, felt and the like.
[0016] In one embodiment, a variety of suitable metal oxide precursors capable of providing metal oxide having desirable properties may be used. For example, a metal oxide precursor may include at least one metal element such as Ti, Zn, Al, Y, Li, B, Na, Ba, Ca, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Zr, Nb, Mo, Ru, Rh, Pd, Ag, W, Pt, Au, Ce or any combination thereof, accordingly, claimed subject matter is not limited in this regard. A metal oxide precursor may be provided in the form of metal alkoxide, metal halide or metal salt; however, claimed subject matter is not limited in this regard. The metal oxide precursor may provide metal oxide by oxidization.
[0017] In other embodiments, at least one titanium oxide precursor may be used. Examples of titanium oxide precursor may include titanium alkoxide, titanium halide, titanium salt and the like however, claimed subject matter is not limited in this regard. Examples of titanium alkoxide may include titanium tetra-methoxide, titanium tetra-ethoxide, titanium tetra-isopropoxide, titanium tetra-butoxide, titanium monomethoxy-triisopropoxide, titanium dimethoxy-diisopropoxide and the like. Examples of titanium halide may include titanium tetra-fluoride, titanium tetra-chloride, titanium tetra-bromide, titanium tetra-iodide and the like. Examples of titanium salt may include Ti(ClO) 2 , Ti(ClO) 3 , Ti(ClO) 4 , Ti(ClO 2 ) 2 , Ti(ClO 2 ) 3 , Ti(ClO 2 ) 4 , Ti(ClO 3 ) 2 , Ti(ClO 3 ) 3 , Ti(ClO 3 ) 4 , Ti(ClO 4 ) 2 , Ti(ClO 4 ) 3 , Ti(ClO 4 ) 4 , Ti(CO 3 ) 2 , Ti(HCO 3 ) 2 , Ti(HCO 3 ) 3 , Ti(HCO 3 ) 4 , Ti(HPO 4 ) 2 , Ti(NO 2 ) 2 , Ti(NO 2 ) 3 , Ti(NO 2 ) 4 , Ti(NO 3 ) 2 , Ti(NO 3 ) 3 , Ti(NO 3 ) 4 , Ti(SO 3 ) 2 , Ti(SO 4 ) 2 , Ti 2 (CO 3 ) 3 , Ti 2 (HPO 4 ) 3 , Ti 2 (SO 3 ) 3 , Ti 2 (SO 4 ) 3 , Ti 3 (PO 4 ) 2 , Ti 3 (PO 4 ) 4 , TiCO 3 , TiHPO 4 , TiPO 4 , TiSO 3 , TiSO 4 and the like.
[0018] An amount of metal oxide formed on a surface of a prepared fiber may vary depending on the concentration of at least one metal oxide precursor and/or at least one metal oxide in a solution. In addition, the amount of metal oxide may be further varied by repeating the number of coatings, etc. In one embodiment, an amount of metal oxide in a solution may be about 0.1 M to about 1 M. In other embodiments, different concentrations of metal oxide in the solution may be used.
[0019] In one embodiment, at least one metal oxide precursor and/or at least one metal oxide may be dissolved in a variety of suitable organic solvents. For example, the solvent may be water, alcohol (for example, methanol, ethanol, propanol, butanol, pentanol and combinations thereof), or any combination thereof.
[0020] In one embodiment, a surface of a carbon fiber is coated with a solution containing at least one metal oxide (for example, titanium oxide). In such embodiment, a crystalline of a metal oxide phase coated on a surface of the fiber may be improved, since a metal oxide having a pre-determined crystalline is used.
[0021] In one embodiment the metal oxide solution includes only one metal element. In other embodiments, metal oxide solution may include two or more metal elements. In some embodiments of the multi-metal solution, various ratios of each metal oxide may be employed. For example, two or more metal elements may be used in a same amount by mole, or, in other embodiments, one of metal elements may have a higher concentration than that of the other metal elements. In one such embodiment, the concentration may be differentiated by doping the main metal oxide phase on the surface of the fiber.
[0022] In one embodiment, a carbon fiber is coated with a solution containing at least one metal oxide precursor and/or at least one metal oxide. The coated carbon fiber may then be dried. In some embodiments, the carbon fiber may be dried using standard methods of drying such as, for example, with unheated air (or other gas or gases), heated air or gas, sunlight, infrared light and the like. Drying may be carried out at a temperature of about 0° C. to about 150° C., in one embodiment. In other embodiments, the drying may be carried out at room temperature to about 150° C. Through the drying process, a solvent may be evaporated and at least one metal oxide precursor and/or at least one metal oxide may be fixed on the surface of a carbon fiber. In another embodiment an additional surfactant is used as described below. A surface of a carbon fiber is coated with a solution containing at least one metal oxide precursor and/or at least one metal oxide and the additional surfactant. In one embodiment, at least a part of the surfactant may be evaporated by the drying process.
[0023] In one embodiment, polycarbosilane melt may be provided to a carbon fiber where at least one metal oxide precursor and/or at least one metal oxide are/is provided. Polycarbosilane may be prepared by a variety of common methods.
[0024] In one embodiment, examples of polycarbosilane may include a polycarbosilane having a main chain of the following formula:
[0000]
[0000] where R1, R2 may include, independently of one another, H, hydroxy, C 1 -C 4 alkyl, C 1 -C 4 alkoxy or phenyl; and n may be an integer between 1 and 30.
[0025] In one embodiment, a softening temperature of polycarbosilane may be above room temperature; for example from about 50° C. to about 300° C. In view of processability, the softening temperature may within the above range. In some embodiments, a molecular weight of the polycarbosilane may range from about 100 to about 50000. In other embodiments, the molecular weight of the polycarbosilane may range from about 200 to about 30000. In yet other embodiments, the molecular weight of the polycarbosilane may range from about 200 to about 20000, or may even range from about 1000 to about 10000 in still other embodiments.
[0026] In one embodiment, a polycarbosilane melt may be formed by heating at a temperature above a softening point. The melt may be coated on the surface of a carbon fiber by a variety of common methods such as, for example, dip coating, spray coating, and the like. A carbon fiber whereon polycarbosilane is coated may be obtained by coating a surface of a carbon fiber with polycarbosilane melt, and cooling it below the polycarbosilane's softening temperature.
[0027] In one embodiment, a fiber including metal oxide may be obtained by heating a carbon fiber whereon metal oxide precursor and/or metal oxide, polycarbosilane and the like are coated. The heating may be carried out in air or other gas or gases, including oxygen gas or combinations thereof. The heating may be carried out at a temperature ranging from about 300° C. to about 1500° C.
[0028] In one embodiment, carbon in a carbon fiber may be oxidized and eliminated from the fiber in the form of carbon dioxide by heating. A metal oxide precursor may be oxidized to form metal oxide on a surface of the fiber. Polycarbosilane may move to inside of the fiber and space between metal oxides (or metal oxide precursors) during heating. Polycarbosilane may be oxidized, to form silica (silicon dioxide).
[0029] In one embodiment, a fiber prepared by heating may include silica and metal oxide. The fiber may include a silica phase formed in a core of the fiber, and a metal oxide phase formed on a surface of the fiber. In some embodiments, the fiber may include oxide of metal such as Ti, Zn, Al, Y, Li, B, Na, Ba, Ca, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Zr, Nb, Mo, Ru, Rh, Pd, Ag, W, Pt, Au, Ce or any combination thereof.
[0030] In one embodiment, titanium oxide may be formed on a surface of a fiber by using a titanium oxide precursor as a metal oxide precursor.
[0031] In one embodiment, titanium oxide may be used as photocatalyst decompose organic materials (e.g., see Nature, vol. 238 (1972), 37-38) by exposing titanium oxide to light. Thus, titanium oxide embodiments may be used to decompose source materials of air pollution, water pollution and the like.
[0032] In some embodiments, titanium oxide on the fibers may include at least some portions having a crystalline structure such as anatase-type, rutile-type, brookite-type and the like. In some embodiments, titanium oxide of the anatase-type may be used to facilitate the photocatalytic effect.
[0033] In one embodiment, titanium oxide may be used as a photocatalyst by illuminating the titanium oxide with ultraviolet light (e.g., the UV light may have wavelength(s) of about 400 nm or less). In other embodiments, a metal oxide precursor other than a titanium oxide precursor may be used to form metal oxide on the surface of a fiber to activate photocatalytic action absorbing visible light. These other metal oxide precursors may form undoped metal oxide in some embodiments. In other embodiments, metal oxide precursors that form doped metal oxide may be used.
[0034] In some embodiments, in addition to titanium oxide, metal oxide capable of effecting photocatalytic activity by itself (for example, V 2 O 3 , ZnO, ZrO 2 , SnO, WO, Fe 2 O 3 , etc.) may be formed on a surface of a fiber. Photocatalytic effect may me increased by combining at least one metal oxide (other than titanium oxide) having photocatalytic activity with titanium oxide.
[0035] In one embodiment, a diameter of the fiber may be about 1 mm or less. In other embodiments, the fiber diameter may be about 100 μm or less. In yet other embodiments, the fiber diameter may be about 10 μm or less, or even about 1 μm or less in still other embodiments. In some embodiments, a thickness of the fiber (which may include coatings of silica and/or metal oxide) may be adjusted by adjusting by controlling a variety of features. For example, the thickness may be adjusted by controlling a thickness of a carbon fiber, an amount and type of polycarbosilane and/or metal oxide precursor, the repeating number of coating, a method and condition of heating and so on.
[0036] In one embodiment, metal oxide may be chemically intimately bonded to a support (i.e., a silica phase) in the fiber. For example, the fiber may be prepared as described above where metal oxide is formed on a surface of a silica phase. Thus, the fiber may reduce detachment of metal oxide particles from a support, compared to a fiber prepared by conventional methods (e.g., where metal oxide in the form of powder is coated on a surface of a support such as silica, metal and the like, or metal oxide is coated on a surface of a support by sol-gel method). In addition, a silica phase may be transparent, and thus photocatalyst may be increased by allowing the light to reach the metal oxide. For example, where titanium oxide formed on a surface of a support made from UV-transparent silica can improve the photocatalyst effect of the titanium oxide.
[0037] In one embodiment, a solution containing at least one metal oxide precursor and/or at least one metal oxide may further contain a surfactant. Various surfactants may be employed in various embodiments. Examples of surfactants may include nonionic or cationic surfactants as described below.
[0038] In some embodiments, nonionic surfactants may include polyoxyethylene-type nonionic surfactant, polyglycerin-type nonionic surfactant, sugar ester-type nonionic surfactant and the like. In other embodiments, nonionic surfactants may be used alone or in mixtures with other surfactants.
[0039] In some embodiments, polyoxyethylene-type nonionic surfactant may include polyoxyethylene alkylether, polyoxyethylene alkylphenylether, polyoxyethylene•polyoxypropylene alkylether, polyoxyethylene fatty acid ester, polyoxyethylene sorbitan fatty acid ester, polyoxyethylene glycerin fatty acid ester, derivatives of polyoxyethylene castor oil or hard castor oil, derivatives of polyoxyethylene wax•lanolin, alkanol amide, polyoxyethylene propylene glycol fatty acid ester, polyoxyethylene alkylamine, polyoxyethylene fatty acid amide, sugar fatty acid ester, polyglycerin fatty acid ester, polyether modified silicon and the like. In some embodiments, polyoxyethylene-type nonionic surfactants may include polyoxyethylene cholesterolether, polyoxyethylene phytosterolether. Such nonionic surfactants may be used alone or in mixtures with other surfactants.
[0040] In embodiments, the alkyl group in polyoxyethylene non-ionic surfactants may be an alkyl group of saturated or unsaturated fatty acid having C 6 ˜C 22 . For example, the alkyl group may be a fatty acid of a single composition such as lauric acid, myristic acid, stearic acid, oleic acid, etc. In addition, the alkyl group may be a mixed fatty acid such as coconut fatty acid, tallow fatty acid, hydrogenated tallow fatty acid, castor oil fatty acid, olive oil fatty acid, palm oil fatty acid, etc., or synthesized fatty acid (including branched fatty acid). In some embodiments, polyoxyethylene non-ionic surfactant may be, for example, C 12 H 25 (CH 2 CH 2 O) 10 OH known as C 12 EO 10 or 10 lauryl ether; C 16 H 33 (CH 2 CH 2 O) 10 OH known as C 16 EO 10 or 10 cetyl ether; C 18 H 37 (CH 2 CH 2 O) 10 OH known as C 18 E0 10 or 10 stearyl ether; C 12 H 25 (CH 2 CH 2 O) 4 OH known as C 12 EO 4 or 4 lauryl ether; C 16 H 33 (CH 2 CH 2 O) 2 OH known as C 16 EO 2 or 2 cetyl ether; or combinations thereof. In some other embodiments, polyoxyethylene(5)nonylphenyl ether (Product Name: Igepal CO-520) may be used.
[0041] In another embodiment, fluoroalkyl groups substituting hydrogen with any number of fluorine may be used as an alkyl group. In a polyoxyethylene non-ionic surfactant, the number of condensations of polyoxyethylene may be within the range of 1˜50.
[0042] In one embodiment, nonionic surfactants may include ethylene oxide/propylene oxide block copolymer.
[0043] Examples of block copolymer may include two-block compound such as poly(ethylene oxide)-b-poly(propyleneoxide), and three-block compound such as poly(ethylene oxide)-poly(propylene oxide)-polyethylene oxide or poly(propylene oxide)-poly(ethylene oxide)-poly(propylene oxide). Examples of block copolymer surfactants may include, for example, Pluronic® product name: P123 [poly(ethylene oxide)-b-poly(propylene oxide)-b-poly(ethylene oxide); EO 20 P 70 EO 20 ], P103, 10R5, F98, 25R4, 17R4 that may be obtained from BASF Corporation.
[0044] In other embodiments, surfactants may include C 6-20 alkyl amine (RNH 2 ) surfactants, for example, oleylamine, octylamine, hexadecylamine, octadecylamine.
[0045] In other embodiments, various amounts of surfactants may be employed. An amount of surfactant may range from about 0.1 to about 10 part by weight based on a solvent of 100 part by weight in some embodiments. In other embodiments, the amount of surfactant may range from about 1 to about 5 part by weight based on a solvent of about 100 part by weight. In still other embodiments, the amount of surfactant may range from about 3 to about 5 part by weight based on a solvent of 100 part by weight.
[0046] In some embodiments, the surfactant may have a molar ratio of at least metal oxide precursor and/or at least metal oxide surfactants ranging from about 40:1 to about 80:1.
[0047] In some embodiments, a mesoporous metal oxide phase surfactant may be formed. In some embodiments, a size of metal oxide formed on a surface of a fiber may be uniform.
[0048] In one embodiment, a pore of the metal oxide phase may have a diameter ranging from about 50 nm or less. In other embodiments, a pore of the metal oxide phase may have a diameter ranging from about 1 nm to about 50 nm. In yet other embodiment, a pore of the metal oxide phase may have a diameter ranging from about 2 nm to about 50 nm. In yet other embodiments, the metal oxide has pores sized such that the metal oxide has an effective surface area ranging from about 200 m 2 /g to about 3000 m 2 /g.
[0049] In some embodiments, a fiber may be processed in the form of fiber bundles, bulky fibers, woven fabric, non-woven fabric, braided fabric, paper, felt and the like. In other embodiments, a fabric pad may be prepared from the fiber using common methods.
[0050] In one embodiment, when a fiber or a fabric pad includes metal oxide capable of photocatalytic activity, the fiber or the fabric pad may be used for decomposing organic materials that may cause air pollution and/or water pollution (e.g., livestock farming waste water, various endocrine disrupters, and the like). In another embodiment, the fiber or the fabric pad may be used as an electric wire. Such embodiments use properties of the metal oxide other than photocatalytic activity. In some embodiments, the fiber or fabric pad uses, for example, gas sensor, electron conductivity properties of the metal oxide.
An Apparatus Including A Fabric Pad
[0051] In some embodiments, an apparatus may include at least one fabric pad prepared from the fiber prepared as described above; and at least one device for fixing the fabric pad.
[0052] In one embodiment, a device for fixing the fabric pad may include a variety of shapes, such as propeller, plate, sheet, cylinder, and sphere. In other embodiments different shapes may be used. A fabric pad may be prepared in order to fit an external shape of a device for fixing the fabric pad.
[0053] In an illustrative embodiment as shown in FIG. 2 , a device for fixing the fabric pad may include a propeller 202 . A fabric pad may be prepared in the shape of the wing of the propeller by processing the fiber as described above. Then, the fabric pad 201 may be fixed outside of the wing of propeller 202 to form a propeller having a fabric pad 203 .
[0054] In one embodiment, a fabric pad may be fixed by simple operation such as fitting or tying the fabric pad to the outside of a fixed device, not by physically or chemically bonding the fabric pad to the outside of the fixed device. Thus, a fabric pad may be easily detached from and reattached to the fixed device. For example, an old fabric pad may be easily removed and replaced with a new one from a device for fixing the pad, when the catalytic activity of metal oxide included in a fiber of a fabric pad is decreased by aging and the like. Further, a fabric pad may be used without any limitation in the shape of a catalyst reactor, or material thereof, since the fabric pad may be manufactured in various shapes.
[0055] In some embodiments, an apparatus may optionally include at least one equipment where a device having a fabric pad is placed in the equipment. For example, an apparatus may include an equipment 306 where a propeller having a fabric pad 305 is placed in the equipment 306 , as shown in FIG. 2 . In FIG. 2 , a propeller having a fabric pad 305 may be rotated to circulate air, water and the like in equipment 306 . As the propeller is rotated, organic materials may contact a surface of the fabric pad. The speed of rotation may be adjusted to control the rate at which the organic materials contact the fabric. Examples of the equipment 306 may include a water reservoir, a water tank, a water bottle, a location around a source of air pollution and the like. In other embodiments, an apparatus including the equipment may include one or more devices having a fabric pad to increase photocatalytic activity.
[0056] In one embodiment, an apparatus may optionally include at least one source of light. For example, an apparatus may include a source of light 301 where light 302 may be emitted, as shown in FIG. 2 . The light 302 emitted from the source of light 301 may illuminate a device having a fabric pad to decompose organic materials on a surface of metal oxide (such as titanium oxide) acting as photocatalyst. Examples of the source of light 301 may include an artificial source of light such as a fluorescent lamp, a glow lamp, an UV lamp, and the like), as well as a natural source of light such as the sun.
[0057] In one embodiment, an apparatus may optionally include at least one light-collecting device. For example, an apparatus may include a light-collecting device 303 where the light 302 from the source of light 301 may be collected to emit light 304 . The light-collecting device may increase the photocatalytic effect of metal oxide by focusing the light 302 emitted from the source of light 301 to form collected light 304 . Examples of the light-collecting device may include a lens, a mirror, a reflector and any combination thereof; however, claimed subject matter is not limited in this regard. In other embodiment, multiple light-collecting devices may be placed in series to concentrate more light.
EXAMPLE
[0058] 4.3 g of titanium isopropoxide and 3.12 g of HCl (35 wt %; for adjusting pH) may be mixed and stirred for 5 minutes at room temperature. Then, the stirred mixture may be added to a solution of 2 g of Pluronic® P123 in 12 g of 1-propanol. The mixed solution may be stirred for 10 minutes at room temperature. A woven carbon fiber whose specific surface area may be about 3000 m 2 /g and diameter may be about 1˜5 μm, may be immersed in said solution and taken out, and the carbon fiber may be dried for one day at room temperature.
[0059] The carbon fiber whereon titanium butoxide may be coated, may be immersed in a melt where polycarbosilane powder (e.g., obtained from Nippon Carbon Co., Ltd.) may be heated and melted at a temperature of about 200° C. The Carbon fiber can be removed from the melt and dried at room temperature to form a polycarbosiline coated fiber.
[0060] Further, a fiber including silica and titanium oxide may be obtained by heating the carbon fiber at a temperature of about 900° C. under the atmosphere containing oxygen gas in a furnace.
[0061] The foregoing detailed description has set forth various embodiments of the devices and/or processes via the use of block diagrams, flowcharts, and/or examples. Insofar as such block diagrams, flowcharts, and/or examples contain one or more functions and/or operations, it will be understood by those within the art that each function and/or operation within such block diagrams, flowcharts, or examples can be implemented, individually and/or collectively, by a wide range of hardware, software, firmware, or virtually any combination thereof. In one embodiment, several portions of the subject matter described herein may be implemented via Application Specific Integrated Circuits (ASICs), Field Programmable Gate Arrays (FPGAs), digital signal processors (DSPs), or other integrated formats. However, those skilled in the art will recognize that some aspects of the embodiments disclosed herein, in whole or in part, can be equivalently implemented in integrated circuits, as one or more computer programs running on one or more computers (e.g., as one or more programs running on one or more computer systems), as one or more programs running on one or more processors (e.g., as one or more programs running on one or more microprocessors), as firmware, or as virtually any combination thereof, and that designing the circuitry and/or writing the code for the software and or firmware would be well within the skill of one of skill in the art in light of this disclosure. In addition, those skilled in the art will appreciate that the mechanisms of the subject matter described herein are capable of being distributed as a program product in a variety of forms, and that an illustrative embodiment of the subject matter described herein applies regardless of the particular type of signal bearing medium used to actually carry out the distribution. Examples of a signal bearing medium include, but are not limited to, the following: a recordable type medium such as a floppy disk, a hard disk drive, a Compact Disc (CD), a Digital Video Disk (DVD), a digital tape, a computer memory, etc.; and a transmission type medium such as a digital and/or an analog communication medium (e.g., a fiber optic cable, a waveguide, a wired communications link, a wireless communication link, etc.).
[0062] Those skilled in the art will recognize that it is common within the art to describe devices and/or processes in the fashion set forth herein, and thereafter use engineering practices to integrate such described devices and/or processes into data processing systems. That is, at least a portion of the devices and/or processes described herein can be integrated into a data processing system via a reasonable amount of experimentation. Those having skill in the art will recognize that a typical data processing system generally includes one or more of a system unit housing, a video display device, a memory such as volatile and non-volatile memory, processors such as microprocessors and digital signal processors, computational entities such as operating systems, drivers, graphical user interfaces, and applications programs, one or more interaction devices, such as a touch pad or screen, and/or control systems including feedback loops and control motors (e.g., feedback for sensing position and/or velocity; control motors for moving and/or adjusting components and/or quantities). A typical data processing system may be implemented utilizing any suitable commercially available components, such as those typically found in data computing/communication and/or network computing/communication systems.
[0063] The herein described subject matter sometimes illustrates different components contained within, or connected with, different other components. It is to be understood that such depicted architectures are merely exemplary, and that in fact many other architectures can be implemented which achieve the same functionality. In a conceptual sense, any arrangement of components to achieve the same functionality is effectively “associated” such that the desired functionality is achieved. Hence, any two components herein combined to achieve a particular functionality can be seen as “associated with” each other such that the desired functionality is achieved, irrespective of architectures or intermedial components. Likewise, any two components so associated can also be viewed as being “operably connected”, or “operably coupled”, to each other to achieve the desired functionality, and any two components capable of being so associated can also be viewed as being “operably couplable”, to each other to achieve the desired functionality. Specific examples of operably couplable include but are not limited to physically mateable and/or physically interacting components and/or wirelessly interactable and/or wirelessly interacting components and/or logically interacting and/or logically interactable components.
[0064] With respect to the use of substantially any plural and/or singular terms herein, those having skill in the art can translate from the plural to the singular and/or from the singular to the plural as is appropriate to the context and/or application. The various singular/plural permutations may be expressly set forth herein for sake of clarity.
[0065] It will be understood by those within the art that, in general, terms used herein, and especially in the appended claims (e.g., bodies of the appended claims) are generally intended as “open” terms (e.g., the term “including” should be interpreted as “including but not limited to,” the term “having” should be interpreted as “having at least,” the term “includes” should be interpreted as “includes but is not limited to,” etc.). It will be further understood by those within the art that if a specific number of an introduced claim recitation is intended, such an intent will be explicitly recited in the claim, and in the absence of such recitation no such intent is present. For example, as an aid to understanding, the following appended claims may contain usage of the introductory phrases “at least one” and “one or more” to introduce claim recitations. However, the use of such phrases should not be construed to imply that the introduction of a claim recitation by the indefinite articles “a” or “an” limits any particular claim containing such introduced claim recitation to inventions containing only one such recitation, even when the same claim includes the introductory phrases “one or more” or “at least one” and indefinite articles such as “a” or “an” (e.g., “a” and/or “an” should typically be interpreted to mean “at least one” or “one or more”); the same holds true for the use of definite articles used to introduce claim recitations. In addition, even if a specific number of an introduced claim recitation is explicitly recited, those skilled in the art will recognize that such recitation should typically be interpreted to mean at least the recited number (e.g., the bare recitation of “two recitations,” without other modifiers, typically means at least two recitations, or two or more recitations). Furthermore, in those instances where a convention analogous to “at least one of A, B, and C, etc.” is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., “a system having at least one of A, B, and C” would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). In those instances where a convention analogous to “at least one of A, B, or C, etc.” is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., “a system having at least one of A, B, or C” would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). It will be further understood by those within the art that virtually any disjunctive word and/or phrase presenting two or more alternative terms, whether in the description, claims, or drawings, should be understood to contemplate the possibilities of including one of the terms, either of the terms, or both terms. For example, the phrase “A or B” will be understood to include the possibilities of “A” or “B” or “A and B.”
[0066] From the foregoing, it will be appreciated that various embodiments of the present disclosure have been described herein for purposes of illustration, and that various modifications may be made without departing from the scope and spirit of the present disclosure. Accordingly, the various embodiments disclosed herein are not intended to be limiting, with the true scope and spirit being indicated by the following claims. | Techniques for coating a fiber with metal oxide include forming silica in the fiber to fix the metal oxide to the fiber. The coated fiber can be used to facilitate photocatalysis. | 8 |
BACKGROUND OF THE INVENTION
The present invention relates to a particular warp size composition for the application to certain yarns of blends of synthetic and natural fibers or wholly of natural or synthetic fibers to improve the overall performance, economics, and handling of same during fabric formation.
It is necessary to apply a warp size composition to textile strands or yarns to permit handling of the materials during fabric formation operations, normally weaving, to preclude damage to the yarns during such operations. In general, from commercial and operational standpoints, size compositions that are applied to the yarns must meet certain criteria for successful use in performance of the intended purposes. For example, irrespective of the yarn materials utilized in fabric formation, the size must adhere thereto throughout the operation to protect the fibers from abrasion due to contact with process equipment or adjacent fibers, and thereafter must be easily removable from the formed fabric to permit further finishing and processing of the fabric.
During the evolution of synthetic polymeric filamentary materials, and spun yarns produced therefrom, it became evident that the general types of sizing compositions historically utilized for application to natural fibrous materials were not satisfactory. Particularly, the synthetic polymeric materials are hydrophobic in nature whereas the natural fibrous materials are hydrophilic in nature. Hence different materials were needed that would properly adhere to the synthetic polymeric yarns.
Natural, or generally hydrophilic fibers such as cotton, linen, rayon and the like may be sized with various forms of starch, such as hydrolyzed starches, dextrins, partially esterified starches,and partially etherified starches. Additionally, water soluble carboxymethyl cellulose, water-soluble hydroxyethyl cellulose, natural gums such as guar, gum arabic, sodium alginate and the like may also be used. The above noted sizing agents for natural fibers are generally film formers, and are not in general suitable for use, per se, on synthetic, polymeric fibers such as nylon, polyester, polyacrylonitrile, and cellulose acetate, and likewise on glass fibers. Particularly, aqueous dispersions or solutions of only the above referred to size agents will not adhere to the synthetic, or glass fibers or filaments to afford the protection necessary during fabric formation.
It has been previously determined that certain polymeric sizing agents which are either water dispersible, water soluble, or soluble in dilute alkaline solutions may be suitably employed to size the hydrophobic, synthetic polymeric fibers and filaments. Exemplary of such polymeric sizing agents, without limitation, include polyacrylic acid, polymers of acrylonitrile, polymers of lower alkyl acrylates, maleic anhydride copolymers, polyvinyl alcohol, polyesters and the like.
Depending upon the chemical structure of the polymeric sizing agent, the agent may be suitable for application to both synthetic filamentary materials and spun yarns that contain synthetic fibrous materials. Certain functional groups, if present, on the polymeric size, may render same unsuitable for spun yarns. For example, if during the processing of same, the size is cross linked or otherwise reacted with the synthetic fibrous material in the blend, easy removability of the size is hindered, if not totally negated.
Today's textile market finds the natural fibers appreciably more expensive than the manmade fibers, whereby blends of the two have been utilized successfully for many fabric end uses. Moreover, the manmade or synethetic fibers possess certain qualities that render yarns or blends containing same desirable due to improved physical properties. A single strand of spun yarn constituted by a blend as mentioned hereinbefore has both hydrophilic and hydrophobic characteristics, and accordingly, in order to apply a size composition thereto that is adequately adherent to both types of fiber constituents, it has generally been accepted that blends of size constituents such as those set forth above should be utilized.
Polyester resins suitable for use in warp size compositions for spun yarns that include synthetic fibers in general, due to the chemical composition of same, are generally adhesive at ambient conditions such that agglomeration of particles of resin occurs, even due to cold flow. Consequently polyester-starch or other textile size compositions utilizing a polyester resin have heretofore been blended at the time of preparation of the aqueous dispersion just prior to use, or prepared and shipped as an aqueous dispersion.
Generally the formation of an aqueous dispersion of a blend of size ingredients whether for spun blends or otherwise is accomplished by mixing the ingredients according to a particular recipe in a cooking vessel along with the dispersing medium, generally water, and bringing the mixture to a desired consistency for application to the yarn. Since formulation is generally conducted just before application, and thus may occur at any hour of the day, potential problems exist with maintenance of uniformity of ultimate size compositions, particularly since unskilled laborers are often involved.
To some extent, attempts have been made to circumvent the above noted problems. A particular example of such an attempt is a size composition referred to in the Lark U.S. Pat. No. 3,981,833 which is directed to a warp size composition that includes starch or some other size ingredient suitable for adhesion to the hydrophilic yarns and a polyester resin suitable for adherence to polyester yarns. The Lark composition is generally directed to a pasted starch blended with a polyester resin. Pasted starch of course refers to an aqueous starch composition which is later blended with the polyester resin at the consumer's location, or alternatively, the two may be preblended, and the aqueous blend shipped to the consumer. Lark thus appears to perhaps reduce problems attendant with formulating the size composition at the time of use, but does not overcome same.
Under all known prior art conditions, the consumer either relied upon unskilled labor in preparation of the size composition, or was required to purchase the preblended aqueous dispersion which included the cost of preblending and shipping the water. The present invention provides a dry, premixed, size composition which alleviates the aforementioned agglomeration or cold flow problems of the polyester constituent; affords ease of bulk handling and package compatibility of ingredients; is economical to transport; is provided to the consumer in a form that eliminates mixing errors, and further attributes improvement in weaving performance of the spun yarns sized therewith. According to the present invention, the polyester resin is provided in particulate form in such a manner that agglomeration is precluded, whereby a proper complete blend of size ingredients may be supplied to the consumer which can then be easily and conveniently dispersed in an aqueous medium as desired.
Polyester resins in general have heretofore been provided in particulate form for certain purposes, e.g., for the formation of casting or molding resins. The Chetakian et al U.S. Pat. No. 3,027,338 is directed to a polyester molding composition that is fiber reinforced. The polyester constituent of the molding composition, in crystalline form, is ground at a low temperature, below the melting point of the resin after which the molding composition is produced. In similar fashion, Cruz et al U.S. Pat. No. 3,931,082, relates to colloidally dispersible microcrystalline polyesters which are hydrolyticly treated to remove amorphous regions after which the polyester is mechanically disintegrated by various techniques, one of which is freeze grinding. Neither Chetakian nor Cruz, Jr., et al, however, in any way relate to a warp size composition for textile materials, and in fact, the polyesters of same are unsaturated and would thus not be suitable for use as textile size ingredients.
U.S. Pat. Nos. 3,546,008 to Shields et al and 4,150,946 to Neel both disclose polyesters suitable for use as textile size compositions and that the resin may be provided in pellet, powder or flake form at the time of preparation of the aqueous dispersion of same. The Shields et al and Neel polyesters, however, are intended for use as polymeric sizes for synthetic filaments and are not suitable in their present form for use as size ingredients according to the present invention since during processing of the yarns with a conventional alkali scour, the polyester size of Shields or Neel would become affixed to the synthetic fibers and could not be easily removed.
The present invention thus affords numerous advantages over prior art warp size compositions for fibrous yarns of synthetic and/or natural fibrous materials as set forth above, and known prior art is not believed to anticipate or suggest same.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide an improved warp size composition for use in the sizing of yarns that contain synthetic fibers, natural fibers, or blends of same.
Another object of the present invention is to provide an improved warp size composition for use in sizing yarns of natural-synthetic fiber blends.
Still further another object of the present invention is to provide a dry warp size composition containing a film former and a particulate polyester resin.
Yet another object of the present invention is to provide an improved complete warp size composition that needs only to be appropriately processed with an aqueous medium prior to use in the sizing operation.
Still another object of the present invention is to provide an improved process for producing a textile warp size composition suitable for sizing of yarns that contain synthetic fibers, natural fibers or blends of same.
Generally speaking, the dry textile warp size composition of the present invention comprises a blend of a polyester resin, said resin including ionic hydrophilic groups therein, said resin further being at least substantially saturated and in particulate form, and a film former, said blend being at least water dispersible, and the particulate polyester resin in said blend being at least substantially non-adherent to adjacent resin particles.
More specifically, the dry textile warp size composition of the present invention contains a film former, such as starch, carboxymethyl cellulose, polyvinyl alcohol or the like, or a mixture of same for use in sizing a hydrophilic component of the textile material, such as a cellulosic ingredient, and a polyester resin that has been provided in particulate form, for example by grinding at a temperature where during the grinding operation, agglomeration of the particulate resin will not occur. Subsequent to, or simultaneous with rendering of the polyester resin into particulate form, the resin is blended with the film former under conditions where the resin is coated with the film former prior to any chance for agglomeration, whereby the polyester resin thereafter remains in particulate form, even under humid conditions. Depending upon the particular polyester resin being utilized, it may be necessary to add a carboxyl neutralizing agent to the composition to render same at least water dispersible. For preferred resins according to the present invention, the amount of alkali added would place pH of the composition in a range of from 51/2 to about 7.
More specifically, the dry textile warp size composition of the present invention contains a particulate polyester resin that possesses adequate adhesive qualities for bonding to the fibrous material to reduce shedding, while being easily removable in a conventional scour, and a film former as exemplified by starch, carboxy methyl cellulose, polyvinyl alcohol or the like. Optionally the blend may also include a lubricant, such as a wax, and other general ingredients such as stabilizers, defoamers, antistats and the like to provide a total size package that only needs dispersing in the aqueous medium.
While preferred polyester ingredients are specifically discussed hereinafter, any polyester could be employed so long as the requisite qualities for a sizing resin are present. Such in general requires substantial saturation to avoid cross linking or other reaction with the synthetic fibrous material, and adequate hydrophilicity to ensure easy removability from the yarn during scouring. As also set forth hereinafter, while for the preferred polyester resins, cryogenic grinding is necessary or preferred to provide the resin in particulate form, suitable polyesters may also be processed otherwise such as by pelletizing, prilling, flaking or the like. For purposes of the present application, only grinding of the polyester is discussed in detail as a means for rendering the resin in particulate form.
The preferred polyester resin for use in size compositions according to the present invention is produced by reacting a glycol such as diethylene glycol with a dicarboxylic acid or the like as exemplified by isophthalic acid and trimetallitic anhydride in the presence of an appropriate catalyst. For suitability as a size resin, the preferred polyesters should have an acid value of at least 20, and preferably at least 30.
The process of the present invention generally includes the steps of providing a polyester resin that is at least substantially saturated and has ionic hydrophilic groups thereon, rendering said resin into particulate form, said particles being of a size to permit dispersion of said resin in an aqueous medium, and mixing a predetermined amount of a film former with said particulate resin to achieve a blend of ingredients in which said resin particles will not adhere to adjacent resin particles under normal shipping and storage conditions.
In the case of the preferred type of polyester, the process of the present invention includes the steps of providing a polyester resin having an acid value of at least about 20, grinding the polyester resin to a particulate size no greater than about 5 mesh U.S. Standard Sieve size under conditions where there is no appreciable agglomeration of the ground resin and mixing a predetermined amount of a film former with the ground resin adequate to coat the surfaces of said ground resin sufficient to preclude agglomeration of the resin at ambient temperature.
Preferably the preferred polyester resin is cryogenically ground, at resin temperatures of 0° F. or lower, with the temperature of the grinding means being lowered, if necessary. Thereafter, and before temperature of the particulate resin reaches a point where agglomeration occurs, the film former is mixed therewith. Alternatively, the film former may be mixed with the resin in the grinder where blending occurs in situ as the resin is being ground. In any event, the film former should coat the particulate resin adequately to preclude subsequent agglomeration or fusion of the resin particles at higher temperature conditions.
DESCRIPTION OF PREFERRED EMBODIMENTS
Dry warp size compositions according to teachings of the present invention are intended for use in the warp sizing of yarns that contain natural or synthetic fibrous material. Yarns spun from fiber blends which include both hydrophilic and hydrophobic fibrous constituents are included as well as spun yarns that contain only natural or synthetic fibers. In like fashion the present size compositions would be suitable for synthetic filamentary materials that have been altered to assume the appearance and characteristics of spun yarns, and such is included in the context of the term yarn as used herein. Hydrophilic constituents of blends are basically naturally occurring fibrous materials or chemically modified naturally occurring fibrous materials such as cotton, linen, rayon, wool and the like. Hydrophobic constituents of the fiber blends are basically synthetic fibrous materials to which a polyester resin will adhere adequately for the intended purpose while being easily removable therefrom. Exemplary of such hydrophobic fibrous materials are nylon, polyesters, polyacrylonitrile, cellulose esters such as cellulose acetate, fiber glass and the like. In a preferred situation, however, the size composition according to teachings of the present invention is directed to spun yarns constituted from polyester-cellulosic fiber blends.
The polyester fibrous materials referred to herein, in general, include, without limitation, fibers prepared from synthetic polymers that are provided by the reaction products of a dicarboxylic acid, or an ester forming derivative of same, e.g., dimethyl terephthalate, condensed with a glycol, e.g., ethylene glycol to provide a polymer of the glycol ester of the dicarboxylic acid. Normally, such polyesters are polyethylene terephthalate and modified polyethylene terephthalates.
Dry warp size compositions according to the present invention include, as essential ingredients, particulate polyester resin having a particle size that permits the resin to form an aqueous dispersion for application onto the textile materials and a film former.
Suitable polyester resins should contain ionic hydrophilic groupings thereon, either anionic in nature as exemplified by alkali salts of carboxylates, sulfates, sulfonates, and phosphates, or cationic in nature as exemplified by quaternary sulfates, quaternary ammonium chloride and the like. Further, the term "ionic hydrophilic" is intended to include those groupings that are initially of hydrophilic character and those groupings that assume hydrophilicity after some treatment, such as after neutralization of carboxyl groups. In like fashion, the polymer should be adequately saturated that reaction or other bonding will not occur between the polymer and the fibrous materials under alkaline or thermal conditions, which would retard removability of the size polymer.
A preferred polyester resin for use in the warp size compositions according to the present invention, as set forth hereinabove, is produced by reacting diethylene glycol with isophthalic acid and trimellitic anhydride in the presence of an appropriate catalyst. The particular combination of ingredients is charged to a polymerization reaction vessel and heated to a temperature in the range of from about 400° to about 450° F., after which the temperature is held for a period of time until an acid value as desired for the polymer is achieved. In a most preferred situation, the reactants include 50.877 moles of diethylene glycol; 40.610 moles of isophthalic acid; 5.500 moles of trimellitic anhydride; and 0.01 percent of a titanium isopropoxide catalyst. This particular combination is reacted at a temperature in the range of 400°-450° F. and cooking continued until a predetermined acid value is achieved. Polyester resins of the preferred type having acid values generally below 20 do not form proper dispersions while high acid value polyesters will go into solution. In general terms, however, the polyester should have an acid value that will enable the resin to form a proper aqueous dispersion, and likewise the particle size of the polyester should be such that a good dispersion is achieved. In the event the polyester is anionic in character, as is preferred according to teachings of the present invention, it is generally necessary to include a carboxyl neutralizing agent adequate to ensure that the composition will be at least dispersible. When the polyester is cationic in nature, however, the carboxyl neutralizing agent is not required. Moreover, the carboxyl neutralizing agent may not be required when the polyester is prepared from ingredients which include a dicarboxylic acid such as sodium sulphoisophthalic acid, for example, where the dispersibility mechanism is present in situ.
Preferred polyester resins, as defined herein following polymerization, are cooled to at least a temperature where resin particles will not adhere to adjacent resin particles and the resin is ground at the reduced temperature. In arriving at appropriate temperature conditions for grinding, consideration should be given to the fact that heat is generated during same. Preferably, the polyester resin is cooled to at least a temperature of 0° F., and most preferably, at least about minus 50° F. The ground particles, while remaining cool, will not agglomerate or adhere to adjacent ground particles. As the temperature of the resin returns toward ambient, however, unless precautions are taken, the resin particles will fuse into a mass of material. Depending upon the temperatures at grinding, it may be necessary to also cool the grinder to preclude adherence of resin to grinder surfaces.
Grinding of the polyester resin provides resin of a particle size, outside surfaces of which will be coated during blending with the film former which precludes subsequent resin agglomeration at ambient temperatures or higher. According to teachings of the present invention, a resin particle size of 5 mesh or smaller, U.S. Standard Sieve Size is preferred.
Softer polyester resins of the type preferred herein are normally more appropriate for use in preparing size compositions for suitable yarns as defined herein since the softer resins exhibit appropriate adhesiveness for adherence to the textile material. Harder resins, which in general do not inherently exhibit such adhesive qualities may, however, be utilized in situations where once the resin is ground to a particular particle size, the surface area of the ground resin will regain moisture adequate to impart sufficient adhesive properties thereto. With this harder type resin, it may not be necessary to reduce the temperature of the resin prior to or during the grinding operation, since the harder polyester resins are generally not plastic at ambient temperature.
In reducing temperature of the polyester resin suitable for grinding, any medium may be utilized that will reduce the resin temperature adequate for grinding same without agglomeration of the ground particles. Without limitation, exemplary of suitable cooling mediums are liquid nitrogen and dry ice. Moreover, as mentioned above, depending upon the temperature reached, it may or may not be necessary to likewise cool the grinder.
It is necessary at some point in the process to blend the particulate polyester resin with a film former adequate to coat the resin such that agglomeration of the resin does not thereafter occur once the resin temperature returns to ambient or thereabout. Preferably, blending of the resin and film former occurs immediately after grinding and before the temperature of the ground polyester resin has increased by a substantial amount. Alternatively, the film former may be introduced into the grinder along with the polyester resin such that grinding and blending are carried out simultaneously. While any apparatus may be utilized for grinding the polyester resin that will accept the appropriate cryogenic conditions and grind the resin to the desired particle size, a hammer mill grinder has been found to be suitable. Obviously where the procedure for providing the resin in particulate form is other than grinding, similar blending considerations must be made, i.e., the film former should be added at a time such that subsequent agglomeration of the resin is precluded.
As little as two to three weight percent of the polyester resin in a dry size composition has been demonstrated to yield improved results over the basic size or film former itself. Preferably, from about 5 to about 60 weight percent polyester resin is employed, though the content of polyester resin can be as high as 90 weight percent. In like fashion, the film former is preferably present in a range of from about 5 to about 90 weight percent. In addition to the particulate polyester resin and film former, as mentioned above, unless the polyester resin is of a particular type that does not require same, sufficient carboxyl neutralizing agent should be utilized to render the polymer dispersible. Generally speaking, for preferred polyesters, pH of the blend would be adjusted within in a range of from about 4.0 to about 8.5, preferably from about 5.0 to about 6.5. The neutralizing agent is generally present in the composition, if utilized, in a range of from about 0.25 weight percent to about 0.5 weight percent. Furthermore, in a preferred arrangement, a small amount of a defoamer such as a propylene oxide-ethylene oxide condensate, is present in the dry size composition. Likewise a lubricant, such as a kettle wax as is normally added during preparation of the size dispersions may be added to the present dry size composition.
In preparing size dispersion according to the present invention, the proper size composition to water recipe is provided in a size cooker and is cooked, preferably with live steam at temperatures of approximately 210° F. for from about 15 to about 45 minutes depending upon desired temperature. The dispersion is then applied to the yarn at temperatures of from about 100° F. to about 210° F., preferably from about 160° F. to about 205° F., and most preferably from about 180° F. to about 195° F.
The present invention can better be understood by reference to the following examples.
EXAMPLE 1
A polyester resin was produced by charging 50.877 moles of diethylene glycol; 40.610 moles of isophthalic acid; 5.500 moles of trimellitic anhydride; and 0.01 percent of titanium isopropoxide to a high temperature stainless steel reactor. The reactor was then heated at a temperature of approximately 450° F. and the formulation was cooked for about 12 hours, until an acid value of from about 65 to about 70 was achieved. After reaching the desired acid value, the resin was poured over a rotating flaking cylinder at a temperature of approximately 40° to 45° F. The polyester flakes produced were then chilled to a temperature of from about 0° F. to about minus 50° F. with dry ice and cryogenically ground in a hammer mill grinder to achieve a particle size of from about 5 to about 50 mesh. Immediately thereafter, 20 weight percent ground polyester resin, 79.25 percent starch, 0.50 percent soda ash, and 0.25 percent Pluronic L-61, a propylene oxide-ethylene oxide condensate defoamer manufactured by BASF-Wyandotte were mixed for 30 minutes in a ribbon blender to provide a dry warp size composition.
The above size composition was dispersed in an aqueous medium as follows. One hundred ninety-five pounds of the size composition and 14 pounds of kettle wax were added to a conventional size cooker into 175 gallons of water at ambient temperature and thereafter heated with live steam to a temperature of approximately 210° F. An aqueous dispersion containing 8.5 weight percent solids resulted. The aqueous size dispersion was thereafter applied to 50/50 polyester-cotton spun yarn at a size box temperature of 204° F. Size pick up ranged from 13.9 to 14.5 percent based on the weight of the yarn. Weaving efficiency of the sized yarns was around 95% compared to around 93% for a conventional size. Easy removal of the size in a conventional scour was evident.
EXAMPLES 2-7
Size compositions as listed in Table I were prepared as set forth in Example 1. The compositions were dispersed in an aqueous medium and the dispersion padded onto polyester/cotton spun yarn. Results similar to those of Example 1 were evident.
TABLE 1______________________________________ Example No. (2) (3) (4) (5) (6) (7)______________________________________Ground Polyester Resin 20% 20 20 50 10 60Starch 30 39.05PVA 79.5 20 89.62CMC 79.5 29.5 49.15Soda Ash .25 .25 .25 .60 .13 .70Defoamer .25 .25 .25 .25 .25 .25______________________________________
EXAMPLE 8
Example 1 was repeated with the exception that 5 weight percent of kettle wax that was blended into the formula. This composition then provided a complete dry size package such that nothing further was necessary at the time of preparing the size composition for slashing except water. Again, good results were attained as was the case with Example 1.
EXAMPLE 9
A size bath was produced from 200 pounds of the size composition of Example 1, 240 gallons of water and 16 pounds of kettle wax, and was applied to 100% polyester ring spun yarn, 26/1 count, at a size box temperature of 190° F. and at a pick up of 9.5 percent based on the weight of the yarn. Normal weaving efficiency with a polyvinyl alcohol size is approximately 96%. With the present size composition, a weaving efficiency of more than 99% resulted. The size was easily removed in a conventional scour.
Having described the present invention in detail, it is obvious that one skilled in the art will be able to make variations and modifications thereto without departing from the scope of the invention. Accordingly, the scope of the present invention should be determined only by the claims appended hereto. | A dry textile warp size composition for use in the sizing of yarns containing natural fibrous materials, synthetic fibrous materials, or blends of same including a polyester in particulate form, a film former, and optionally a lubricant and other minor additives. The polyester is preferably rendered into particulate form by grinding at reduced temperature, includes anionic hydrophilic groups and is at least substantially saturated. A process for producing the size composition is also disclosed and claimed. | 3 |
BACKGROUND OF THE INVENTION
The present invention relates to material employed in vehicles for panels including those used for impact absorption in the event of an accident.
A wide variety of materials have been employed in vehicles for panels such a headliners, door panels and the like. U.S. Pat. No. 4,828,910 discloses one such material. Behind decorative panels padding or other impact absorbing techniques are employed for minimizing injuries in the event of an accident. Although air bags are now becoming commonplace, areas of the vehicle, such as the A-pillars and the headliner, need to meet or exceed the federally mandated head injury criterion (HIC(d)) performance which will be required for such areas in future vehicles. In the past, a variety of open and closed cell foam materials have been employed for areas such as the instrument panel. In order to provide head impact absorption in contemporary vehicles, padded visors are sometimes employed as shown in U.S. Pat. No. 4,958,878 for protecting the occupants in the front windshield area.
In recent years, headliners for vehicles have been integrally molded and have a variable thickness depending upon the area of the headliner. In some instances, efforts have been made to increase the thickness of headliners in areas where impact absorption may be important. With such increased thickness, however, the cost of manufacturing the headliner through a molding process increases as does the complexity of the size and shapes of the molds employed. Further, modern vehicles do not allow space for a significant additional conventional padding or cushioning materials in view of the more compact interior design and sharply slanting windshield.
U.S. patent application Ser. No. 08/529,366 filed Sep. 18, 1995, and entitled HEADLINER WITH INTEGRAL IMPACT ABSORPTION PANELS represents one new solution to the problem in which corrugated material is employed in the headliner in critical areas where impact absorption is desirable.
SUMMARY OF THE PRESENT INVENTION
The system of the present invention provides yet an even more economical solution to the formation of decorative panels including those for impact absorption by utilizing recycled material and waste material from headliner manufacturing and, in addition, provides a moldable material which can be configured to provide differing panel shapes and/or impact absorption characteristics.
Panel material embodying the present invention comprises a panel made of about 40-60% recycled, reground thermoplastic fibers mixed with about 60-40% reprocessed thermo-formable fibrous bats including polyester fibers, glass fibers and a thermo-setting resin used in the manufacture of headliners. In one preferred embodiment of the invention, the material comprises a 50% mixture of reground fibers and reprocessed headliner material which is carded to produce a mat which is compression moldable. The reground fibers are shredded, and the resultant mat is heated and compression formed in a cold tool to the desired panel shape. In one embodiment of the invention, the preformed shape is superimposed on a base which is an elongated arch-shaped member to conform to the shape of an A-pillar. In a preferred embodiment, the curvilinear projections are sinusoidal shaped. In another embodiment, a face sheet of planar material is bonded to a preformed shape including such sinusoidal projections.
Thus, with the panel material of the present invention, a relatively inexpensive material is employed and can be shaped to fit any desired area of the vehicle including those where impact absorption is desirable and molded to specifically fit tubular members such as an A-pillar of a vehicle or other structural members. These and other features, objects and advantages of the present invention will become apparent upon reading the following description thereof together with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a fragmentary perspective view of a vehicle including a panel in the form of an impact absorption member of one embodiment of the present invention;
FIG. 2 is a cross-sectional view of the impact absorption member taken along section line II--II of FIG. 1;
FIG. 3 is a fragmentary side elevational view of the structure shown in FIG. 2;
FIG. 4 is a top plan view of the impact absorption member shown in FIGS. 2 and 3;
FIG. 5 is a block diagram of the method of manufacturing a panel of the present invention;
FIG. 6 is a G-force deceleration diagram of comparative tests;
FIG. 7 is a fragmentary perspective view of an alternative embodiment of the invention; and
FIG. 8 is a side elevational view of the structure shown in FIG. 7 mounted to a sheet metal vehicle body part.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring initially to FIG. 1, there is shown a vehicle 10, such as an automobile, including a windshield 12, a roof 14 supported to the vehicle body by a structural steel A-pillar 16 extending between the windshield 12 and the side window 18. The A-pillar extends, thus, from the vehicle frame at the side of the instrument panel 19 to the roof 14. The A-pillar 16 is covered by an impact absorption member 20 of the present invention which, in turn, is covered by a molded, decorative cover 22 to provide a clean trim appearance to the interior of the vehicle. Roof 14 is covered by a molded headliner 15 which can be an integral one-piece structure. The roof beam area above windshield 12 and other locations may also include a preformed impact absorption member such as that shown in FIGS. 7 and 8 described below. Turning now to FIGS. 2 and 3, the impact absorption member's geometric shape is first described followed by a description of its composition and method of manufacturing.
FIG. 2 is a cross-sectional view taken along section line II--II in FIG. 1 and shows the impact absorption member 20 as having a base 24 which is shaped to conform to the cross-sectional configuration of the generally rectangular A-pillar 16. Thus, base 24 includes a pair of outwardly projecting lower flanges 26, 28, upwardly extending walls 25, 27 and a top 29 all integrally formed. The flanges 26, 28 extend continuously along the length of the impact absorption member 20 as seen in FIG. 3; however, the sidewalls 25, 27 and top 29 are interrupted by integrally formed curvilinear projections 30 which, in the preferred embodiment, have a sinusoidal shape when viewed from the side (FIG. 3) and a generally rounded arch shape as viewed in FIG. 2.
In the embodiment of the invention of FIGS. 1-6, the sinusoidal wavelength (the distance from one peak 32 to the next adjacent peak 32) of the curvilinear projections 30 was 1". The depth of the projections from the top 29 of base 24 and peak 32 was, in the preferred embodiment, 1.2", while the overall width from edge to edge of the flanges 26 and 28 was 3.2". The thickness of the material was substantially uniform and comprises about 1/16". The width of each of the rounded projections 30 from one sidewall 34 to an opposite sidewall 36 (FIG. 4) was approximately 0.5" with the edges 38 of the curvilinear projections being generally arch-shaped, as seen in FIG. 2, and rounded, as also seen in the top view of FIG. 4.
The material employed for manufacturing the impact absorption member 20 or other panels including decorative panels, such as headliners, door panels and the like, is preferably made of a mixture of recycled thermo-formable material in combination with waste material from the manufacture of a headliner from the material disclosed in U.S. Pat. No. 4,958,878, the disclosure of which is incorporated herein by reference. The headliner manufacturing involves the trimming of the final headliner shape and the scrap material from such trimming process is employed with the recycled thermo-formable material to form the crushable material employed for the impact absorption member 20. The method of manufacturing the material is now described in connection with FIG. 5.
In FIG. 5, recycled thermo-formable material, such as waste fibers from carpet manufacturing is employed. The fiber density can be from 1-10 denier and be made of polypropylene, polyethylene, nylon or PET. This material is employed as shown by block 40 and is shredded into strips of about 11/2-2 in length depending on the material being recycled. This step is indicated by the shredding step of block 42 utilizing a commercially available shredding machine. At the same time, a supply of scrap or waste headliner material is employed as indicated by block 50 and is stretched and separated into strips by pairs of rollers having needle-like projections as indicated by the step of block 52. The somewhat similar size and shapes of the thermo-formable material and headliner material are mixed and carded in a carding machine and process as indicated by block 45 to form a mat, as indicated by block 46, of, in the preferred embodiment, a mixture of about 50% reground thermo-formable material and about 50% of reprocessed headliner material. The thermo-formable material serves as a binder for the glass fibers of the headliner material and the blend of thermo-formable material and headliner material can vary from about 40-60%, respectively, to about 60-40%, respectively.
The resultant mat of blended material has a thickness of about 3/4-1" and a mat area density of about 1800 g/m 2 . The mat is heated to a temperature of about 420° in surface heaters which heat opposite sides of the mat sufficiently to melt and fuse the thermo-formable material with glass fibers. The heated blend retains the mat-like shape and is fed into a compression mold tool at room temperature (about 72° F.) which forms the final shape of the panel as indicated by block 54. If the panel is a decorative panel, such as a door panel, upholstery is bonded or laminated to the panel either simultaneously with the molding step 54 or as a separate step as indicated by block 55.
It has been discovered that the curvilinear projections 30, such as shown in FIGS. 1-4, which are made of the material of the manufacturing process represented in FIG. 5 provide a slower and controlled deceleration of a head form eliminating sharp spikes in G-force loading in the event of an impact during an accident. The material itself is crushable and, although shaped to retain its configuration during incidental bumping, deforms and crushes during an impact which would otherwise cause head injuries. The decorative covering 22 hides the arch-like curvilinear projections 30 from view. FIG. 6 shows the impact force of a 10-pound head form under a simulated 15 m.p.h. crash. Waveform A represents the spike-shaped fatal deceleration encountered when the head form strikes a naked steel A-pillar. Waveform B shows the dramatic effect of the use of the impact absorption material of the present invention where the maximum G-force is less than 1/3 that of the uncovered A-pillar and exceeds the Federal Motor Vehicle Safety Standard No. 201 requiring an HIC(d)<1000.
Referring now to FIGS. 7 and 8, there is shown an alternative embodiment of the present invention in which an impact absorption member 65 includes elements 60 and 70. Element 60 is a planar sheet 60 of material, of the same type as manufactured by the process shown in FIG. 5, is made and has a thickness of about 1/16". Bonded to the sheet 60 of such material is a washboard patterned sheet 70 of the same material also having a thickness of 1/16" and which has a sinusoidal pattern of peaks 72 and troughs 74 with the troughs 74 being bonded to the upper surface 62 of sheet 60 by any number of bonding steps such as hot melt glue, ultrasonic welding, heat staking or the like. The composite structure forms an impact absorbing member which, as seen in FIG. 8, can be attached to a sheet metal member 80 on a vehicle, such as vehicle 10 shown in FIG. 1. Member 80 can be one of the roof beams or other area requiring impact absorption. The absorption characteristics of member 65 is similar to that shown in the diagram B of FIG. 6. In the embodiment shown in FIGS. 7 and 8, the distance between adjacent peaks of the patterned sheet 70 is about 1" while the distance between the peaks 72 and troughs 74 is approximately 3/4". This construction is particularly well suited for mounting to planar surfaces such as a wide sheet metal beam 80 of a vehicle roof.
Planar sheet 60 in the preferred embodiment comprises the same thickness of material as manufactured by the process shown in FIG. 5, however, in some embodiments, a significantly thicker, lower density material could also be employed. Sheet 60, as manufactured by the process shown in FIG. 5, is a relatively stiff and rigid thin sheet. A relatively thick resilient sheet also could be employed, such a sheet having a thickness of, for example, 3/4" and a significantly lower area density than sheet 60, which is the same as that described in connection with FIGS. 2-4, namely 1800 g/m 2 .
Yet another embodiment of the invention is shown in FIG. 9 in which an impact absorption member 90, of the material made according to the process shown in FIG. 5, is formed in a three-dimensional or curved configuration to mate with a similarly curved body part of a vehicle. Member 90 is an integral sheet including a sinusoidal pattern of peaks 92 and valleys 94 which peaks can be spaced approximately 1" apart with the height between the peaks and valleys being approximately 3/4" as in the embodiment shown in FIGS. 7 and 8. In this embodiment, however, the sheet alone is attached by bonding to a mating curvilinear surface of a vehicle.
Although in the preferred embodiment of the invention the reprocessed waste headliner material is employed, the shredded recycled thermo-formable material could be mixed with a similar percentage blend of glass fibers or polyethylene tetraphthalate (PET) fibers in some applications. It will become apparent to those skilled in the art that various modifications to the preferred embodiment of the invention as described herein can be made without departing from the spirit or scope of the invention as defined by the appended claims. | A vehicle panel material comprises a mixture of recycled, reground thermo-formable material and reprocessed headliner material which includes fibrous bats with polyester fibers, glass fibers and a thermo-setting resin. The method of manufacturing such material includes the steps of shredding thermo-formable material into strips; shredding headliner material comprising thermo-formable fibrous bats, glass fibers and thermo-setting resin; mixing and carding the thermo-formable material and headliner material into a mat; heating the mat to at least partially melt the thermo-formable material; and shaping the mat into a vehicle panel. | 3 |
BACKGROUND OF THE INVENTION
(1) Field of the Invention
This invention relates to a method of increasing high density lipoprotein (HDL)-cholesterol levels in serum. In particular it relates to methods of increasing serum HDL-cholesterol levels by use of certain phenylethylamine derivatives.
(2) Description of the Prior Art
Coronary artery disease (CAD) in the United States accounts for 650,000 deaths annually at a cost of over $28.5 billion per year (American Heart Association Heart Facts. 1978, Dallas). It is the most common cause of death in this country. Over the years considerable research effort has been directed at finding factors which alter CAD risk. Factors associated with increased risk of CAD include smoking, hypertension, obesity, hyperlipidemia, inactivity, diet, being male, and genetic factors. On the other hand alcohol consumption, exercise, thinness, being female, and genetic predisposition are factors associated with decreased risk of CAD.
Much effort has been made to correct CAD risk factors including weight reduction, hypertension control, exercise, low cholesterol and saturated fat diet, smoking reduction, and lipid reducing agents. Lipid lowering products have been used in hyperlipoproteinemias in order to arrest, reverse, or prevent atherosclerosis. Typical of such substances are lecithin, pectin, cottonseed oil, and the mucilaginous substances listed in U.S. Pat. No. 3,148,114. In addition, several synthetic hypolipidemic agents are now available, namely, clofibrate, D-thyrozine, cholestyramine, and nicotinic acid [(Levy & Frederickson, Postgraduate Medicine 47, 130 (1970)].
Other useful hypolipidemic agents disclosed in the prior art and N,N'-disubstituted-p-phenylenediamines (U.S. Pat. No. 3,819,708) -αtertiary butyl-p-phenoxybenzlyamines (U.S. Pat. No. 3,946,119) and bis-substituted benzyl methanamines (U.S. Pat. No. 4,035,508).
If a drug could be found which increased HDL concentration, then ingestion of this substance might reduce the risk of CAD. Alcohol consumption has the above properties, however, its abuse potential and toxicity limit its practical usefulness.
High density lipoprotein (HDL)-cholesterol concentration has been found to be the best serum predictor of coronary artery disease (CAD). High levels of HDL are associated with a low risk of CAD and low levels with a high risk of CAD. High density lipoprotein appears to be the cholesterol "scavenger" of the body--it removes cholesterol from cells and carries it to the liver for excretion. Since factors which are associated with protection from coronary artery disease (exercise, alcohol consumption, estrogen, thinness, genetics) are associated with high HLD-cholesterol levels, it has been proposed that elevated serum HDL may bring about the protection. In fact, HDL has been called the "antiatherogenic lipoprotein".
Recent reports have revealed that four Beta-adrenergic blockers (propranolol, metoprolol, atenolol, sotalol) lower HDL levels. Hooper, P. L.: Effect of Propranolol on Plasma Concentrations of HDL Apoproteins and Lipids. Br. Med. J. 6157:200, Jan. 1979; Bielmann, P. & Leduc, G.: Effects of Metoprolol and Propranolol on Lipid Metabolism. Int. J. Clin. Pharmacol Biopharm. 17:378-382, 1979. England, J. D. F.: et al. The Effect of Metoprolol and Atenolol on Plasma HDL Levels in Man. Clin. Exp. Pharmacol. Physiol. 7:329-33, 1980. Lehtonen, A.: Long-Term Effect of Sotalol on Plasma Lipids. Clin. Sci. 57:Suppl. 5:405 s -7 s , 1979.
SUMMARY OF THE INVENTION
I have now discovered that certain of the sympathomimetic amines, i.e., those which are Beta receptor stimulants, are capable of increasing HDL-cholesterol concentration. Those preferred are the Beta 2 receptor stimulants, as their presently known pharmacologic action is essentially on bronchi and not the heart. Thus, the amines found useful in the practice of this invention are derivatives of phenylethylamine represented by the following structural formula: ##STR3## wherein R 1 is a member selected from the group consisting of --CH(CH 3 ) 2 , --C(CH 3 ) 3 and ##STR4## R 2 is a member selected from the group consisting of --OH and --CH 2 OH; R 3 and R 4 are members selected from the group consisting of --H and --OH. Terbutaline, metaproterenol, fenoterol and salbutomal, all known beta 2 agonists, satisfy the above formula and will be found satisfactory in the practice of the invention.
BRIEF DESCRIPTION OF THE DRAWING
The sole FIGURE of the drawing shows two curves showing the effect on serum HDL-Cholesterol of the administration of terbutaline on two patients over a five week period.
DETAILED DESCRIPTION OF THE INVENTION
The phenylethylamine derivatives useful in the practice of this invention can be administered orally or parenterally, oral administration being preferred since patients usually will take these agents for a number of years. Various pharmaceutical prepartions can be made suitable for this purpose by following the conventional techniques of the pharmaceuticl chemist. These techniques involve granulating and compressing when necessary or variously mixing and dissolving or suspending the ingredients as appropriate to the desired end product. Numerous pharmaceutical forms to carry the compounds can be used. For example, the pure compound can be used or it can be mixed with a solid carrier. Generally, inorganic pharmaceutical carriers are preferable and particularly solid inorganic carriers. One reason for this is the large number of inorganic materials which are known to be pharmaceutically safe and acceptable, as well as being very convenient in preparing formulations. The compositions may take the form of tablets, linguets, powders, capsules, slurries, troches or lozenges, and such compositions may be prepared by standard pharmaceutical techniques. Tablet compositions may be coated or uncoated and they may be effervescent or non-effervescent. Conventional excipients for tablet formations may be used. For example, inert diluents, such as magnesium carbonate or lactose, disintegrating agents such as maize, starch or alginic acid, lubricating agents such as magnesium stearate and sweetening agents such as sucrose, lactose, or saccharin may be added, or a flavoring agent such as peppermint, oil of wintergreen, or cherry flavoring may be used. A preferable tablet composition is one which comprises from about 1 to about 10 milligrams of a compound of this invention.
If a liquid carrier is used, the preparation may be in the form of a soft gelatin capsule, a syrup, a liquid solution or suspension. A syrup or elixir may contain the active compound sucrose, as a sweetening agent, methyl and propylparabens as preservatives, a dye and flavoring such as cherry or orange flavor. Of course, any material used in preparing any dosage unit form should be pharmaceutically pure and substantially non-toxic in the amounts employed. In addition, the active ingredients may be incorporated into sustained-release preparations and formulations.
The hydrocarbon solubility of most of the compounds of this invention is high enough to allow the use of pharmaceutically-acceptable oils as carriers. For example, vegetable or animal oils such as sunflower oil, safflower oil, maize oil or codliver oil can be used. Glycerine can also be used. With this latter solvent, from 25 to 30 percent water may be used. When water alone is the carrier, or when the solubility of the compound in the oil is low, the preparations can be administered in the form of a slurry.
Emulsion compositions may be formulated using emulsifying agents such as sorbitan trioleate, polyoxyethylene sorbitan monooleate, lecithin, gum asacia or gum tragacanth. Aqueous based suspensions may be prepared with the aid of wetting agents such as polyethylene oxide condensation products of alkylphenols, fatty alcohols or fatty acids and with suspending agents, for example a hydrophilic colloid such as polyvinylpyrrolidone. The emulsions and suspensions may contain conventional excipients such as sweetening agents, flowing agents, coloring materials and preservatives.
The compounds of this invention may be administered in the form of a nutritive preparation in which the active ingredient is mixed with protein, such as casein, and carbohydrates. In addition to the active ingredient, dietary supplements such as vitamins, salts of glycerophosphoric acid, choline, inositol and amino acids such as methionine may be added.
The percentage of the compound to be used in the pharmaceutical carrier may be varied. It is necessary that the compound constitute a proportion such that a suitable dosage will be obtained and it is preferred to use pharmaceutical compositions containing at least 0.5 weight percent of the compound. Activity increases with concentration of the agent in the carrier, but those compositions containing a significant amount of carrier, (98 to 99.5 percent carrier) are preferred as they allow for the easier administration of the compound.
For parenteral use, the compounds of this invention can be formulated with sterile ingredients, compounded and packaged aseptically. They may be administered intravenously or intramuscularly. Useful solvents for formulation in such use are the polyhydric aliphatic alcohols and mixtures thereof. Expecially satisfactory are the pharmaceutically acceptable glycols, such as propylene glycol, and mixtures thereof. Glycerine is another example of a polyol which is particularly useful. Up to 25-30 percent by volume of water may be incorporated in the vehicle if desired. An 80 percent aqueous propylene glycol solution is a particularly conveninet solvent system. A pH range, about 7.4, and isotonicity compatible with body isotonicity, is desirable. Basicity may be controlled by addition of a base as required, and a particularly conveninet base is monoethanolamine. It may often be desirable to incorporate a local anesthetic and such are well known to those skilled in the art. For example, lidocaine (p-di-ethylamine-2, 6-acetoxylidide, available from the Astra Chemical Co.), may be employed at a level of up to about 20 mg/cc., or even more.
It is not intended that the dosage regimens of the compounds be limited to any particular range. The dosage range desired in this invention is that range necessary to accomplish the desired end of increasing HDL-cholesterol, to the extent desired. The increase in HDL-cholesterol level desired will not be the same for all patients, but depends on such factors as initial HDL-cholesterol level, patient's sex, obesity, cigarette smoking, diet, predominance of one form of lipid over another, etc. The dosage, whether oral or parenteral, must, therefore, by necessity be individually determined by the physician. Likewise, the concentration range of the compounds in the various formulations of this invention is not limited. The concentration should be high enough to avoid an excessive number of administrations per day, but low enough to allow flexibility in administration.
Administration of the compounds of this invention by the oral route is preferred. Preferred daily dosages can be as low as 5 mg. Higher dosages can be given. Generally, one uses as a small a dose as will afford the desired response. This reduces chance of appearance of undesirable side effects. A convenient upper limit is about 18 milligrams per person per day. A preferred range of daily dosage is about 5 to 15 milligrams. In terms of body weight preferred dosages are from 0.05 to 0.3 mg. per kg. of body weight per day with a preferred range of about 0.1 to 0.25 mg. per kg. of body weight per day. The daily dosage is preferably administered from one to four or five times daily in amounts of from about 2.5 mg. to about 5.0 mg. and these amounts may be administered in dosage units containing at least 2.5 mg. of the compound. For example, when administering the compound in tablet form several tablets containing from, say 2.5 to 4 mg. of active compound can be administered up to 4 or more times daily. Alternatively, larger dosage units containing more of the compound, say 4 to 5 mg. can be administered at less frequent intervals.
For parenteral applications daily dosages of from about 5% to about 25% of the oral dosages are preferred. Thus daily dosages can be as low as 0.01 mg. to about 0.05 mg. per kg. body weight. The maximum dosage is determined only by physical limitations. A convenient upper limit is about 3 mg. From about 0.1 to about 0.3 mg. per injection (dosage unit in concentrations of about 0.5 to 1 mg./c.c., with from 2 to 5 injections of from 0.1 c.c. to 0.5 c.c. daily will give the required amount. Preferred formulations will contain from 0.5 to 1 mg./c.c. to be given in one injection of from 0.1 c.c. to 5 c.c.
Larger or smaller doses can be used and, in some cases, might be preferred in individual cases. Likewise administration need not be on a daily basis, although this is preferred, but may be, for example, on alternate days or even weekly and the like. With either oral or parenteral use, a daily regimen is preferred. However, even a single administration will have some effect.
Although the administration of the phenylethylamine derivatives has been more particularly disclosed earlier as being either orally or parenterally, it will be appreciated by those skilled in the art that these compounds can also be administered by either a metered dose inhaler or as an inhalant solution. In the case of a metered dose, the derivatives can be administered as is usual as a micronized powder in an inert propellant. Each metered dose expressed from the inhaler will deliver at the mouth piece the desired amount of compound for a unit dosage, as earlier disclosed. Where the phenylethylamine derivatives used in the practice of the invention are administered as an inhalant solution, the particular derivative will be supplied as a solution in an inert diluent such as saline solution commonly used for this purpose. Oral inhalation is administered with the aid, according to usual technique, of a hand bulb nebulizer or an intermittent positive pressure breathing apparatus. Various solutions can obviously be made up, e.g., a 5% solution in bottles of 10 ml. with accompanying calibrated dropper, but this will depend on a number of factors as earlier disclosed including the particular dosage requirements for a particular patient.
The active ingredient can be administered in the form of a salt, if desired. For example, terbutaline sulfate is commercially available in both tablet form and in ampules for subcutaneous injection from Astra Parmaceutical Products, Inc., Worcester, Massachusetts under the brand name BRICANYL.
The population that would benefit from a rise in HDL-cholesterol concentration is large since 40% of the United States population die of CAD. Subjects that are of particular risk for CAD are men, smokers, obese subjects, people with a family history of CAD, inactive subjects, and nonethanol consumers.
The invention will be better understood in conjunction with the following specific example.
METHODS
After giving informed consent, 15 healthy, nonobese men 23 to 45 years old with normal serum cholesterol levels were studied. The subjects were nonsmokers and nonjoggers, and they were asked not to alter habits known to alter lipid metabolism, such as alchohol ingestion and diet. After a base-line lipid profile was obtained during fasting, the 15 subjects received a 2.5 mg. BRICANYL® terbutaline sulfate tablet (containing the equivalent of 2.05 mg. free base, white in color, NDC product code 725) orally four times a day for a two-week period. Two additional subjects received the terbutaline sulfate tablets at the same dose for a two-week period. Two additional subjects received the terbutaline sulfate tablets at the same dose for a five-week period. Fasting-state lipid values were determined weekly during terbutaline administration and again one week after the drug was stopped.
While subjects were fasting, serum was analysed for concentration of cholesterol (Levine, J. B. and Zak B.: Automated Determination of Serum Cholesterol. Clin Chim Acta. 10:381-4, 1964), triglyceride (Kessler G. and Lederer H.: Flourimetric Measurement of Triglycerides. In: Automation in Analytical Chemistry: Technician Symposia. White Plains, N.Y,: Mediad Inc., 341-4, 1965), and HDL cholesterol (Lopes-Virella M. F., Stone P., Ellis S., and Colwell, J., A. Cholesterol Determination in High Density Lipoprotein Separated By Three Different Methods. Clin Chem. 23:882-4, 1977). Lipid values corresponded with primary standards prepared by the Centers for Disease Control, Atlanta. Values for LDL cholesterol were calculated according to the procedure of Friedewald et al. Friedewald W. T., Levy, R. I., Fredrichson, D. S. Estimation of the Concentration of Low-Density Lipoprotein Cholesterol in Plasma, Without Use of The Preparative Ultracentrifuge, Clin. Chem. 18:499-502, 1972. Statistical analysis was conducted by two-factor analysis of variance, followed by the Newman-Keuls test. Zar J.H. Biostatistical Analysis. Englewood Cliffs, N. J.: Prentice-Hall, 170, 1974.
The table below shows that a rise in HDL-cholesterol concentration was associated with two weeks of terbutaline administration in 15 subjects. After one week of terbutaline administration, the HDL-cholesterol concentration had increased significantly (P<0.005). By the second week, HDL-cholesterol levels had risen 10 percent from the base-line value (from 40.8 to 44.9 mg. per deciliter [1.06 to 1.16 mmol per liter]; P<0.005). One week after terbutaline administration was stopped, HLD-cholesterol values returned to near the base-line values. Total cholesterol, triglyceride, and LDL-cholesterol levels did not change significantly throughout the study.
______________________________________Serum Lipid and Lipoprotein Levels in 15 Subjects ReceivingTerbutaline*Substance Base Line 1 week 2 Weeks 1 Week Off______________________________________Total cholesterol, 149.1 ± 146.3 ± 147.7 ± 150.2 ± 17.6(mg/dl) 17.1 15.9 13.0Triglyceride, 109.3 ± 104.1 ± 105.2 ± 111.8 ± 36.5(mg/dl) 35.8 29.4 24.0LDL-cholesterol, 86.4 ± 81.2 ± 83.3 ± 85.9 ± 17.1(mg/dl) 16.4 17.6 13.9HDL-cholesterol, 40.8 ± 44.2 ± 44.9 ± 42.7 ± 7.0(mg/dl) 6.2 7.2.sup.+ 6.6.sup.+______________________________________ *Values are expressed as means of 15 determination ±S.D. To convert cholesterol values to millimoles per liter, multiply by 0.02586. To convert triglyceride values to millimoles per liter, multiply by .sup.+ P<0.005 as compared with the baseline value.
Turning now to the figure of the drawing there is shown the effect of five weeks of terbutaline administration in two subjects. HDL-cholesterol levels rose to a maximum at two weeks and continued to be elevated throughout the period of terbutaline administration. HDL-cholesterol returned to base-line values one week after terbutaline administration was stopped.
The study demonstrates that the administration of terbutaline, a beta-adrenergic agonist, is associated with a significant rise in HDL-cholesterol values. The magnitude of the increase is comparable to that of the rise in HDL-cholesterol seen in men who have joined a cardiac rehabilitation program (Erkelens, D. W., et al. High-density Lipoprotein-Cholesterol in Survivors of Myocardial Infarction. JAJA 242:2185-9, 1979).
It should be understood that the specific embodiments described herein are merely exemplary of the preferred practice of the present invention and that various modifications and changes may be made in the particular embodiments described herein without departing from the spirit and scope of the present invention. | High density lipoprotein (HDL) levels in serum cholesterol are increased by orally administering phenylethylamine derivatives having the structural formula ##STR1## wherein R 1 is a member selected from the group consisting of --CH(CH 3 ) 2 , --C(CH 3 ) 3 and ##STR2## R 2 is a member selected from the group consisting of --OH and --CH 2 OH; and R 3 and R 4 , respectively, are members selected from the group consisting of --H and --OH. | 0 |
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application claims priority to International Patent Application number PCT/EP2014/051241, filed on Jan. 22, 2014, which claims priority to German Patent Application number 10 2013 100 961.1, filed on Jan. 30, 2013, and German Patent Application number 10 2013 105 339.4, filed on May 24, 2013, and is hereby incorporated in their entirety.
FIELD
[0002] The disclosure relates to a method for distributing power among a plurality of DC sources, which are connected in parallel to an input-side DC link of a DC-to-AC converter. Furthermore, the disclosure relates to an inverter, which has a DC-to-AC converter comprising an input-side DC link, a plurality of inputs for a parallel connection of a plurality of DC sources to the DC link, and at least one DC-to-DC converter, which is arranged between one of the plurality of inputs and the DC link and is actuable in order to cause a change in the power fed via said DC-to-DC converter into the DC link.
BACKGROUND
[0003] A known multistring inverter is the product “Sunny TriPower” by the Applicant. The plurality of DC-to-DC converters of a multistring inverter make it possible to operate the strings connected via said DC-to-DC converters in each case independently of one another at their maximum power point (MPP), i.e. at the operating voltage at which the maximum electric power is generated by the strings. In this case, the DC-to-DC converters are typically boost converters, which step up the operating voltage of the individual strings to the DC-link voltage of a common DC link, which is an input DC link of the DC-to-AC converter. In the case of the product “Sunny TriPower”, the deration of the power of a string always takes place in the direction of its off-load voltage. In this case, first the string with the greatest voltage difference between its operating voltage and the DC-link voltage is relieved of load in the event of deration of the power of the DC-to-AC converter, so that its operating voltage increases in the direction of its off-load voltage. Only when this string has been completely relieved of load or when the voltage difference is equal to the voltage difference for a second string is the second string also relieved of load. As a result, minimization of the power losses in the individual DC-to-DC converters in the form of boost converters is achieved, as well as adjustment of their power losses. As already explained, the shift in the operating voltage in the case of inverters of this type always takes place in the direction of the off-load voltage of the individual strings. Therefore, when the installation is dimensioned, it is necessary to ensure that the maximum off-load voltage of the strings does not exceed the maximum permissible DC-link voltage.
[0004] In a known version of the multistring inverter “Sunnyboy” by the Applicant, the possibility is provided to the installation operator to extend the range of the possible operating voltages of the strings. In order that the DC-link voltage does not exceed its maximum permissible value nevertheless, in the case of deration of the power of the DC-to-AC converter the operating voltage is shifted in the direction of a short circuit of the respective string, i.e. from the MPP towards lower voltages. This makes it possible to design the strings in such a way that the maximum MPP voltage is approximately equal to the maximum permissible DC-link voltage. Specifically, during control of this known multistring inverter, even prior to the connection of the strings to form a common DC link, it is detected whether a voltage-extending string, i.e. a string with an off-load voltage above the maximum permissible DC-link voltage, is present. Run up of the MPP of such a string is then performed from the range of low operating voltages of the string; and, during deration of the power of the DC-to-AC converter, such a string is operated at reduced operating voltages. Other strings which are not voltage-extending are shifted, during the deration, towards higher operating voltages, i.e. towards their off-load voltage, on the other hand, because a better, in particular quicker deration capacity of the power thereof is provided in this direction owing to the profile of the characteristics of the strings. If a string which initially is not voltage-extending becomes voltage-extending nevertheless owing to changed operating conditions, i.e. for example during deration of its power by increasing its operating voltage in the direction of its off-load voltage, an operating voltage above the permissible DC-link voltage is achieved, the operating voltage of the affected string and possibly substrings connected in parallel to said string and connected to the same DC-to-DC converter is short-circuited, as a result of which a further increase in the DC-link voltage is prevented. Then, the power fed in by the multistring inverter needs to be run up again. As a result, losses during feeding occur since the currently permissible power of the DC-to-AC converter can only be fed again after a few seconds in the case of renewed run up owing to a maximum increase in the power ramp. In general, it is of interest to exhaust the power which can presently be fed by the DC-to-AC converter as much as possible.
[0005] US 2011/0101784 A1 discloses a hybrid wind and solar inverter. In this case, power is fed to an electrical grid from alternative voltage sources. Depending on the demand for electric power on the grid, the electric power from the individual voltage sources is connected to the grid or buffer-stored.
[0006] EP 2 284 382 A2 discloses an energy supply system, in which electrical energy which is provided by various voltage sources on a power bus is consumed locally or is buffer-stored in the form of heat.
[0007] EP 2 104 200 A1 discloses a method for actuating a multistring inverter for photovoltaic systems, which multistring inverter has a separate DC-to-DC converter on the input side for each string. In order to improve efficiency, one or more electrical variables, to be precise input current, input voltage and/or input power, are measured at each DC-to-DC converter, and at least one of the DC-to-DC converters changes its operating state in the event that a limit value and/or a window is exceeded, depending on this measurement, in such a way that its power losses are reduced. For example, the DC-to-DC converter can be disconnected when a boosting of the operating voltage of the string connected thereto, initiated by it, is no longer required because the operating voltage reaches the DC-link voltage.
[0008] WO 2012/017068 A2 discloses a method for detecting a feed-in energy quantity, which has been potentially possible but has not actually been fed in within a time period, of a photovoltaic system comprising one or more inverters for feeding electrical energy from one or more photovoltaic generators into an AC grid. Said method is intended in particular for detecting the feed-in power which has been potentially possible during deration. In order to enable this detection, the inverter(s) is/are operated differently during the deration, wherein the different operating modes comprise operation at the MPP or at least for detecting the characteristic of the strings connected to the respective inverter. Specifically, one or more inverters can each be operated at the MPP, and the power of the other inverters can be reduced more significantly in order to achieve the desired deration than if the deration were to be distributed uniformly among all of the inverters. In another specific embodiment of the known method, the characteristics of the string(s) connected to the inverter is sampled regionally or completely, and the thus varying power of the inverter is buffer-stored or compensated for at different times, so that the required power reduction, when averaged over time, is achieved. The demands placed on the deration of the electric power and in particular on the provision of negative deration power do not permit short-term overshooting with the electric power provided by an inverter either, however. In order to feed a constant electric power despite the variable electric power of the inverter, WO 2012/017068 A2 proposes buffer-storing the difference between the different electric power and the constant electric power or converting it into other forms of energy. For this purpose, however, additional devices are then required.
SUMMARY
[0009] The disclosure is based on the problem of disclosing a method for controlling an inverter which simplifies utilization of the maximum power that can be fed without additional complexity in terms of apparatus.
[0010] The disclosure proposes providing a method for distributing power among a plurality of DC sources, which are connected in parallel to an input-side DC link of a DC-to-AC converter. At least one of the DC sources is connected, via a DC-to-DC converter, to the DC link, wherein the DC-to-DC converter is actuable in order to cause a change in the power fed into the DC link by the DC source. During derated operation of the DC-to-AC converter, in which the power of the DC-to-AC converter is derated with respect to the sum of the maximum powers available from all DC sources, the powers of the DC sources are derated differently, and, by actuation of at least the at least one DC-to-DC converter via which the at least one DC source is connected to the DC link, a variation in the power of at least one other DC source is compensated for dynamically.
[0011] Why the variation in the power of the at least one other DC source occurs is in principle irrelevant even if embodiments of the present disclosure actively bring about such variations. The fact that the variation is compensated for dynamically means that, by actuation of the at least one DC-to-DC converter, the power fed into the DC link by the at least one DC source is increased or decreased to such an extent that the power fed into the DC link in total from the at least one DC source and the at least one other DC source follows an external preset, without any buffer-storing of power which goes beyond the effects of a conventional DC-link capacitor, and is constant for this purpose, for example. This is equivalent to any power increase of individual DC sources being compensated for by a corresponding power reduction of the remaining DC sources. Therefore, a balancing equation of the following form results with the changes in power over time ∂P i /∂t of a single DC source:
[0000]
∑
i
=
1
n
∂
P
i
∂
t
=
0
,
[0012] where the sum goes beyond the number n of all of the DC sources of the inverter. This balancing equation applies in particular to a narrow time scale, with the result that ripple of the DC-link voltage is kept as low as possible. In this case, the ripple of the DC-link voltage is lower the shorter the response time of the remaining DC sources or the DC-to-DC converters via which said DC sources feed their powers into the DC link to the change in power of a specific DC source.
[0013] The precondition for this is therefore that the power fed into the common DC link always corresponds to the power which can flow at that time as a maximum via the DC-to-AC converter, in particular into an AC grid which is intended to be stabilized with the aid of the deration of the DC-to-AC converter. In this case, the power to which the DC-to-AC converter is derated can for its part be variable dynamically. Thus, by virtue of the method according to the disclosure, regulation power can also be provided by the inverter despite the variation in the power of the at least one other DC source.
[0014] In one embodiment, the at least one DC source has a photovoltaic generator, which is connected to the DC link of the DC-to-AC converter via the actuable DC-to-DC converter. A photovoltaic generator can be varied in terms of its power very quickly by virtue of its operating point being shifted by the DC-to-DC converter. Thus, very high dynamics are possible when compensating for the variation in the power of the at least one other DC source. In particular, these dynamics are much greater than, for example, in the case of a generator comprising an electric machine as DC source, in which the moment of inertia of a rotor of the electric machine is already in opposition to higher dynamics during changing of the output power.
[0015] For a high dynamic power, it is advantageous if a plurality of DC sources each have a photovoltaic generator, which is connected to the DC link of the DC-to-AC converter via an actuable DC-to-DC converter, with which DC-to-DC converter an MPP tracking for the respective photovoltaic generator is also possible. The inverter in the method according to the disclosure can also be a multistring inverter, in which all of the DC sources each have at least one string of photovoltaic cells and in each case, or nevertheless at least apart from one, are connected to the common DC-to-AC converter via an actuable input-side DC-to-DC converter. The operating point of a DC source which is connected to the DC link directly or via a DC-to-DC converter with a fixed transformation ratio can be varied by varying the DC-link voltage using the DC-to-AC converter of the inverter.
[0016] The at least one other DC source, whose power variation is compensated for by actuation of the DC-to-DC converter assigned to the at least one DC source, can also have a generator comprising an electric machine, however. This generator can be connected to the DC link of the DC-to-AC converter without a DC-to-DC converter which is actuable in order to cause a change in the power fed into the DC link by the at least one other DC source. If the generator is an AC generator, said AC generator is combined in the DC source with a downstream AC-to-DC converter. Specifically, the at least one other DC source may be, for example, a wind turbine or a diesel generator, which themselves only have low dynamics of the power that can be provided thereby. By combining with the at least one highly dynamic DC source on the basis of a photovoltaic generator, this deficiency is eliminated in the method according to the disclosure, however.
[0017] It goes without saying that the power output by each DC source is detected in the method according to the disclosure in order to be able to implement the power compensation between the DC sources. It furthermore goes without saying that the power of the DC sources is detected at at least the same rate at which there is a response, to react with the aid of the at least one DC-to-DC converter, to the variations in the power of the at least one other DC source. In one embodiment, the sampling rate at which the power of the DC sources is detected is even higher, for example twice as great. The sampling rate or measuring frequency can be more than 100, more than 1000 or else more than 10,000 Hz. A typical rate at which the power of the DC sources is detected is in the range of from 8 to 50 kHz. The rate at which the power of the at least one DC source is adjusted by actuation of the at least one DC-to-DC converter in order to respond to variations in the power of the at least one other DC source, on the other hand, is more than 10 Hz, or more than 100 Hz or at least 1,000 Hz. Specifically, it is presently in a range of from 4 to 25 kHz. This corresponds to a response time of the at least one DC-to-DC converter to variations in the power of the at least one other DC source of from 40 to 250 μs. Even a rate of more than 10 Hz already corresponds to a response time of less than 100 ms, and therefore less than half the conventionally allowed conversion time of an inverter connected to an AC grid in response to a sudden reduction in the AC power of 200 ms. In general, it should be stated that the quality and robustness of the method according to the disclosure increases as the measurement frequency increases and as the response time of the at least one DC-to-DC converter to variations in the power of the at least one other DC source decreases.
[0018] The power of the DC-to-AC converter is typically derated in accordance with external presets, wherein these presets can be preset by the respective operator of the grid into which the DC-to-AC converter feeds, explicitly or by parameters of the grid. The distribution of the power among the individual DC sources then takes place dynamically within the method according to the disclosure, i.e. in accordance with internal presets.
[0019] In the method according to the disclosure, the variation in the power of the at least one other DC source can be caused by variations in the operating conditions of the other DC source, such as, for example, a photovoltaic generator or a wind turbine. In various embodiments of the method according to the disclosure, the power of the at least one other DC source is varied intentionally, i.e. actively, however, in order to use in a targeted manner the time for the deration of the power of the DC-to-AC converter.
[0020] This includes in particular that at least part of the characteristic of the DC sources, i.e. in the case of a multistring inverter all of the strings connected to the DC link via in each case one DC-to-DC converter or all of the strings connected to the DC link directly, is detected in order to detect the MPP thereof during derated operation as well. In this case, the aim of this detection can be the determination of the present maximum available power in order to demand a remuneration for this. However, the aim may also be to be able to run up the respective MPP directly after the deration. This can also be considered to be a measure to maximize the feed-in power, in this case directly after the deration.
[0021] In order to detect the MPP of a DC source, said MPP is in one embodiment run up directly. In order to discover it it is expedient to run down the characteristic of the respective DC source as completely as possible. The variation in the power of the respective DC source occurring in the process is compensated for dynamically in accordance with the disclosure by suitable actuation of the at least one DC-to-DC converter.
[0022] By running down the characteristic during deration, it is also possible to identify which of the DC sources connected to the DC link are voltage-extending, i.e. have a present off-load voltage above the maximum permissible DC-link voltage. The operating voltage of these DC sources should be varied in the case of deration in the short-circuit direction instead of in the off-load direction in order to avoid a situation whereby the maximum permissible DC-link voltage is exceeded. This applies in particular in the case of a multistring inverter.
[0023] The method according to the disclosure not only allows the identification of voltage-extending DC sources, however, but also makes it possible to transfer said DC sources from an operating state close to off load into an operating state close to short circuit without needing to short circuit said DC sources. The higher power flowing in the meantime into the common DC link is compensated for dynamically by the at least one DC-to-DC converter.
[0024] The variation in the power of the at least one other DC source can also be performed from the point of view of finding an operating point for all of the DC-to-DC converters at which optimization of the operation of the inverter is provided from a superordinate point of view. Such a superordinate point of view may be, for example, minimized power losses in the entire inverter or else only all of the DC-to-DC converters. A matching of the power losses of individual DC-to-DC converters with one another can also be such a superordinate point of view. A further point of view would be a minimized loading of the components of the DC-to-DC converters and/or of the DC-to-AC converter or else an optimized regulation capacity of the power of the DC-to-AC converter in order to maximally exhaust the respectively valid upper limit of the power of the DC-to-AC converter.
[0025] As has already been indicated, an inverter according to the disclosure comprising a DC-to-AC converter having an input-side DC link, comprising a plurality of inputs for a parallel connection of a plurality of DC sources to the DC link, comprising at least one DC-to-DC converter, which is arranged between one of the inputs and the DC link and is actuable in order to cause a change in the power fed via said DC-to-DC converter into the DC link, and comprising a control device is characterized by the fact that its control device actuates the at least one DC-to-DC converter in accordance with the method according to the disclosure. In this case, the control device can comprise a primary control device, which regulates the power of the DC-to-AC converter in accordance with external presets, and a secondary control device, which distributes this power dynamically among the individual inputs for the DC sources, with actuation of the at least one DC-to-DC converter. For this purpose, actuable DC-to-DC converters are provided in all inputs. In the case of one of the inputs, however, an actuable DC-to-DC converter can be dispensed with since the DC-link voltage can be varied by the DC-to-AC converter in order to vary the operating point of the DC source connected to this input. In this case, dispensing with an actuable DC-to-DC converter can mean both that no DC-to-DC converter is provided at all and also that a DC-to-DC converter with a fixed transformation ratio is provided.
[0026] In an operating mode without deration of the power of the DC-to-AC converter, the control device can actuate the DC-to-DC converters and possibly the DC-to-AC converter for individual MPP tracking of the connected DC sources. This applies in particular in the case of the formation of individual, a plurality of or all of the DC sources as photovoltaic generators and particularly in the case of a multistring inverter according to the disclosure.
[0027] Advantageous developments of the disclosure are set forth in the patent claims, the description and the drawings. The advantages of features and of combinations of a plurality of features mentioned in the description are merely by way of example and can take effect alternatively or cumulatively without the advantages necessarily needing to be achieved by embodiments in accordance with the disclosure. Without the subject matter of the attached patent claims being altered hereby, the following applies in respect of the disclosure content of the original application documents and the patent: further features can be gleaned from the drawings, in particular the illustrated relative arrangement and interactive connection of a plurality of component parts with respect to one another. The combination of features of different embodiments of the disclosure or of features of different patent claims departing from the selected back-references of the patent claims is likewise possible and is suggested hereby. This also relates to those features which are illustrated in separate drawings or are mentioned in the description thereof. These features can also be combined with the features of different patent claims. Likewise, features listed in the patent claims can be dispensed with for further embodiments of the disclosure.
[0028] The features mentioned in the patent claims and the description should be understood in respect of their number such that precisely this number or a greater number than the mentioned number is provided, without the explicit use of the adverb “at least” being required. If, therefore, the discussion refers to one element, for example, this should be understood to mean that precisely one element, two elements or more elements are provided. These features can be supplemented by other features or can be the only features from which the respective product consists.
[0029] The reference symbols contained in the patent claims in no way restrict the scope of the subjects protected by the patent claims. They merely serve the purpose of making the patent claims more easily understandable.
BRIEF DESCRIPTION OF THE DRAWINGS
[0030] The disclosure will be explained and described in more detail below on the basis of exemplary embodiments with reference to the attached drawings.
[0031] FIG. 1 shows a simplified circuit diagram of a first embodiment of the inverter according to the disclosure.
[0032] FIG. 2 shows the power plotted over time for two DC-to-DC converters of an inverter given a constant power of a common DC-to-AC converter of the inverter.
[0033] FIG. 3 shows the power plotted over time for three DC-to-DC converters of an inverter as shown in FIG. 1 , wherein the characteristic of the strings connected to one of the two DC-to-DC converters is run down, which is compensated for by another one of the DC-to-DC converters.
[0034] FIG. 4 shows the power plotted over time for three DC-to-DC converters of an inverter as shown in FIG. 1 , wherein the characteristic of the strings connected to one of the two DC-to-DC converters is run down, which is compensated for by the two other DC-to-DC converters; and
[0035] FIG. 5 shows a simplified circuit diagram of a further embodiment of the inverter according to the disclosure.
DETAILED DESCRIPTION
[0036] The disclosure relates to a method for distributing power among a plurality of DC sources, which are connected in parallel to an input-side DC link of a DC-to-AC converter, which method has the features of the preamble of independent patent claim 1 . Furthermore, the disclosure relates to an inverter, which has a DC-to-AC converter comprising an input-side DC link, a plurality of inputs for a parallel connection of a plurality of DC sources to the DC link, and at least one DC-to-DC converter, which is arranged between one of the plurality of inputs and the DC link and is actuable in order to cause a change in the power fed via said DC-to-DC converter into the DC link.
[0037] In particular, a plurality of or all of the DC sources can comprise a photovoltaic generator having at least one string of photovoltaic cells. If all of the DC sources are designed in this way, a corresponding inverter is also referred to as a photovoltaic inverter. If, in addition, the operating point of all of the DC sources can be set individually by actuating corresponding DC-to-DC converters, the term multistring inverter is used. A string of photovoltaic cells is in this case understood to mean at least a series circuit of a multiplicity of photovoltaic cells. However, a plurality of such series circuits can also be connected in parallel in a string. In this case, each of these parallel-connected series circuits is referred to as a substring. The photovoltaic cells can in this case be combined in groups to form photovoltaic modules, which are then for their part connected in series to form a string or substring.
[0038] The deration of the power of inverters with which photovoltaically generated electrical energy is fed into an AC grid can be required for stabilization of the AC grid. The deration can take place to a fixed percentage, i.e. a percentage which is constant over time for a certain period of time, of the rated power of the respective inverter. However, it can also take place dynamically, i.e. taking into consideration a preset directed to the instantaneous power requirement on the AC grid on the basis of limit values which vary over time. In any case, the deration provides negative regulating power for the AC grid.
[0039] Irrespective of whether the deration takes place dynamically or rather statically and the reason for which the deration is performed, the present disclosure is concerned with distributing the derated power of the DC-to-AC converter among the various DC-to-DC converters of the inverter.
[0040] FIG. 1 shows the basic design of an inverter 1 . The inverter 1 comprises a plurality of two-pole inputs 26 , to which in each case a DC-to-DC converter 2 , typically a boost converter, is connected. A DC source 25 is connected to a common DC link 5 via each of the inputs 26 . Each DC source 25 has at least one string 3 of photovoltaic cells 4 . The DC link 5 is the input DC link of a common DC-to-AC converter 6 . The number of photovoltaic cells 4 of each string 3 can be much greater than is illustrated here. Each string 3 can also comprise a plurality of substrings connected in parallel. The number of inputs 26 can likewise be greater than is illustrated here. However, it is also possible for only two inputs 26 to be provided. The DC-to-DC converters 2 are typically boost converters, with which, despite a uniform DC-link voltage across a DC-link capacitor in the DC link 5 , each string 3 can be operated at an individual operating voltage in order to obtain the maximum electric power of the string 3 under the present operating conditions. This electric power is provided to the DC-to-AC converter 6 via the DC link 5 , and said DC link feeds said power as alternating current into an external AC grid 8 . The DC-to-AC converter 6 and the DC-to-DC converters 2 are controlled by a control device 9 . If an operator 10 of the AC grid 8 transmits a deration signal 11 , which is received by the control device 9 , the control device 9 derates the DC-to-AC converter 6 correspondingly using a control device element 12 . In this case, said control device receives a power signal 13 describing the present power of the DC-to-AC converter 6 and transmits an actuation signal 14 to the DC-to-AC converter 6 . It goes without saying that the signals 13 and 14 can be combined from different partial signals, for example from a current measurement and a voltage measurement in the case of the signal 13 and from a plurality of actuation signals for the individual semiconductor switches of the DC-to-AC converter 6 in the case of the signal 14 . The control device 9 distributes the derated power among the individual DC-to-DC converters 2 via a further control device element 15 and also in the process receives power signals 16 and outputs actuation signals 17 . In this case, the actuation signals 17 are generated depending on the power signals 16 in such a way that the sum of the powers of the DC-to-DC converters 2 which flow into the DC link 5 correspond to the derated power fed into the AC grid 8 by the DC-to-AC converter 6 . Variations in the power of one of the DC-to-DC converters 2 are compensated for by opposing variations in the powers of at least one other DC-to-DC converter 2 , so that the derated power of the DC-to-AC converter 6 is always available in the DC link 5 and therefore the maximum permissible power can be fed into the AC grid 8 . This applies both in the case of regulation of the power of the DC-to-AC converter 6 to a fixed value, such as, for example, a certain percentage of the rated power of the DC-to-AC converter 6 , and in the case of regulation to limit values which vary over time, which are determined on the basis of the instantaneous power demand of the AC grid 8 . In this case, in particular the latter case corresponds to a provision of regulating power for the AC grid 8 with the aid of the DC-to-AC converter 6 , i.e. a dynamic variation in the power fed into the AC grid 8 by the DC-to-AC converter 6 in accordance with external presets.
[0041] Although a three-phase inverter is illustrated in FIG. 1 , the use of a single-phase or two-phase inverter is also possible.
[0042] FIG. 2 illustrates, for an inverter comprising two DC-to-DC converters and a common DC-to-AC converter, how a constant power 18 , which is fed into an AC grid 8 by the DC-to-AC converter, is distributed dynamically among the powers 19 and 20 of the two DC-to-DC converters 2 and the DC sources 25 connected via said DC-to-DC converters to the DC link 5 shown in FIG. 1 . A variation in the power 19 of one DC-to-DC converter is compensated for by an opposite variation in the power 20 of the other DC-to-DC converter. In this case, this dynamic compensation takes place with a fast response time in the region below 10 ms, for example, in the region of 1 ms or less. Thus, despite the variation in the power 19 of one DC-to-DC converter, the voltage across the DC-link capacitor 7 shown in FIG. 1 , the power 18 which is fed into the AC grid 8 by the DC-to-AC converter, and therefore also an average power 22 of all of the DC sources 25 and, in this case equivalent thereto, an average power 22 of the DC-to-DC converter 2 connected thereto can be kept constant. The average power 22 of the DC sources 25 should in this context and below be understood to mean the average contribution of each of the DC sources 25 in total connected to the inverter 1 to the power 18 of the DC-to-AC converter 6 . This condition also applies in particular in time-dependent fashion, i.e. the average power 22 of each DC-to-DC converter 2 results at any time t from the quotient of the power 18 of the DC-to-AC converter 6 and the number of DC-to-DC converters 2 to be assigned in total to the inverter 1 . Since in the present case the inverter is an inverter comprising in total two DC-to-DC converters 2 , the average power 22 of these two DC-to-DC converters 2 is half the power 18 of the DC-to-AC converter 6 .
[0043] In the case illustrated, the powers 19 , 20 of one DC-to-DC converter and the other DC-to-DC converter, apart from the compensation in accordance with the disclosure, are at the same level of average power 22 . However, it is also possible for the power 19 of one DC-to-DC converter and the power 20 of the other DC-to-DC converter 2 to be at different levels. For example, the power 19 of one DC-to-DC converter 2 can be a certain magnitude or percentage greater than the power 20 of the other DC-to-DC converter 2 , without the compensation in accordance with the disclosure, or vice versa. It is essential that in each case the sum of the powers of all the DC sources 25 connected to the inverter 1 corresponds to the preset power 18 of the DC-to-AC converter 6 .
[0044] FIG. 3 illustrates profiles of the power P over time t for an inverter comprising three DC-to-DC converters 2 and a common DC-to-AC converter 6 as shown in FIG. 1 . The power 18 of the DC-to-AC converter 6 is constant over time and is derated with respect to the maximum power available at the DC-to-DC converters. The power 19 of one DC-to-DC converter corresponds to its characteristic versus its operating voltage, which has been increased over time t at a constant rate. That is to say that although the DC-to-DC converters 2 do not feed the maximum powers available from the strings connected thereto into the common DC link 5 , during the deration of the power 18 , the MPPs 21 of the individual DC-to-DC converters 2 or of the strings 3 connected thereto are detected. This can take place once with the aim of documenting the maximum available power for the demand for remuneration. Another aim may be to be able to run up the MPPs immediately again as soon as the deration of the power 18 has come to an end. A passing through the MPP 21 from a range of high operating voltages close to off-load into a range of low operating voltages close to short circuit can additionally take place with the aim of transferring a string 3 which, as part of the deration, comes close to a voltage extension, i.e. a higher operating voltage than the maximum permissible DC-link voltage across the DC-link capacitor 7 of the common DC link 5 , to an operating point which is closer to short circuit with approximately the same power, but a lower operating voltage. The power 19 which is increased in the process at the MPP 21 of one DC-to-DC converter is compensated for by a reduced power 20 of one of the other two DC-to-DC converters 2 . Therefore no interruption of the feed of power 18 is necessary, which would be associated with a feed-in loss beyond the deration forced externally. The remaining other DC-to-DC converter 2 has, in this example, a power which is equal to the average power 22 . The average power 22 of all the DC-to-DC converters 2 in this case remains constant over time since the power 18 of the DC-to-AC converter 6 is also constant over time in the illustrated range. Since in this example the inverter is a multistring inverter comprising in total three DC-to-DC converters, the average power 22 of the DC-to-DC converters corresponds to a third of the power 18 of the DC-to-AC converter 6 . It is also possible for the power 18 of the DC-to-AC converter to follow a preset, time-variable setpoint curve. In this case, too, it is essential that the powers of all of the DC sources 25 connected to the inverter 1 add up to the preset power 18 of the DC-to-AC converter 6 at any time t.
[0045] FIG. 4 illustrates similar power profiles to those shown in FIG. 3 . However, in this case the power 19 of one DC-to-DC converter 2 or of the strings 3 connected thereto, which power passes through the MPP 21 , in contrast to FIG. 3 , is not only compensated for by an opposite variation in the power 20 of another DC-to-DC converter 2 . Instead, the opposite variation is in this case distributed among a plurality of, in this case two, other DC-to-DC converters 2 with correspondingly reduced powers 20 . The variation in the powers 20 with respect to an average power 22 of all of the DC-to-DC converters 2 is therefore only half as great as the variation in the power 19 with respect to the average power 22 . Thus, it may also be possible, for example, when all of the strings are already operating at a relatively high operating voltage, for the temporary power increase to be compensated for by the other DC-to-DC converters when the first string arriving in the voltage-extending range is transferred to low operating voltages close to short circuit. This is only possible with difficulty, but sometimes even not at all, in the case of an inverter 1 comprising only two DC-to-DC converters 2 since in this case a change in power of one string 3 alone needs to be compensated for by an opposite change in power of the precisely one other string 3 . The degree of freedom for an active power change of an individual DC-to-DC converter 2 or of the strings 3 connected thereto therefore increases with the number of DC sources 25 connected in total to the inverter 1 . For the degree of freedom of a dynamic power change, in this case the DC-to-DC converters 2 present within the inverter 1 are important.
[0046] By virtue of the power being redistributed dynamically between the individual DC-to-DC converters 2 as shown in FIG. 1 as part of a search or tracking method, an operating point of the entire inverter 1 can also be determined empirically by virtue of particularly good account being taken of a superordinate point of view. This superordinate point of view may be, for example, minimized power losses, a minimized component loading or a maximized, i.e. quick and anyhow stable regulation capacity of all of the powers. Such a superordinate point of view can also be the matching of the power losses of individual DC-to-DC converters 2 to one another in respect of uniform loading of their components during operation. In this way, in particular the lives of individual components to be expected in different DC-to-DC converters 2 can be matched. Premature failure of individual components of a DC-to-DC converter in comparison with components of identical design of another DC-to-DC converter is thus effectively prevented.
[0047] FIG. 5 shows an inverter 1 , which differs from the inverter 1 shown in FIG. 1 in terms of the following details. In addition to the inputs 26 with the actuable DC-to-DC converters 2 , the inverter 1 has a further two-pole input 23 , via which a DC source 24 is connected directly to the common DC link 5 . In this case, the current flowing from the DC source 24 into the DC link 5 is detected in the input 23 exclusively by a current sensor 27 and communicated to the control device 9 as power signal 16 . The specific power in this case results together with the DC-link voltage of the DC link 5 , which is contained in the power signal 13 of the DC-to-AC converter 6 . The DC source 24 can have, instead of a photovoltaic generator, in particular a generator comprising an electric machine. The electric machine can in this case be driven, for example, by a wind turbine or a diesel engine. Such DC sources are also referred to as wind turbines or diesel generators. A DC source can also comprise an AC generator, with an AC-to-DC converter connected downstream thereof. DC sources which have a generator comprising an electric machine are on their own less dynamic owing to the moment of inertia of their rotor, which also concerns deliberate variations in their powers which they feed into the DC link 5 . They are therefore less suitable as the only current sources if the power of the DC-to-AC converter 6 is intended to be varied dynamically in order to provide regulation power for the AC grid 8 . These dynamics are achieved in the case of the inverter 1 shown in FIG. 5 by the DC sources 25 connected in parallel in each case by means of an actuatable DC-to-DC converter 2 to the common DC link 5 in the form of strings 3 or photovoltaic generators, however. However, a further photovoltaic generator in the form of a string 3 could also be connected to the input 23 without any actuable DC-to-DC converters 2 . In the case of this photovoltaic generator, despite the actuable DC-to-DC converter 2 which is not provided in the input 23 , MPP tracking could then be implemented. For this purpose, the DC-link voltage which forms as a voltage drop across the DC-link capacitor 7 of the DC link 5 would need to be varied by targeted actuation of the DC-to-AC converter 6 . Even in the case of any other DC source 24 , the operating point thereof can in this way be varied by the inverter 1 shown in FIG. 5 . Any resultant variation in the power which is fed by the DC source 24 into the DC link 5 is compensated for dynamically by actuation of the actuable DC-to-DC converters 2 in order to cause complementary power variations. | In order to distribute power over multiple direct current sources which are connected in parallel to an input-side direct voltage intermediate circuit of a DC/AC transformer, at least one of which direct current sources is connected to the direct voltage intermediate circuit via a DC/DC transformer, wherein the DC/DC transformer can be actuated to change the power fed into the direct voltage intermediate circuit by the direct current source, the power levels of the direct current sources are decreased differently in a decreased operating mode of the DC/AC transformer in which the power of the DC/AC transformer is decreased compared to the sum of the maximum power levels available from all the direct current sources, and by actuating at least the one DC/DC transformer via which the at least one direct current source is connected to the direct voltage intermediate circuit, variation in the power levels of at least one other direct current source is compensated dynamically. | 7 |
FIELD OF THE INVENTION
The present invention relates to a topical formulation containing an NSAID, most favorably, diclofenac. Other NSAIDs include, without limitation, etodolac, ketorolac, bromfenac, diflunisal, ibuprofen, fenoprofen, ketoprofen, naproxen, suprofen, meclofenamate, mefenamic acid, piroxicam, meloxicam, indomethacin, sulindac, phenylbutazone, oxyphenbutazone, and tolmetin. The topical formulation is particularly useful for alleviating pain/inflammation associated with infection caused by herpes virus, especially herpes simplex virus (HSV) and varicella-zoster virus (VZV).
BACKGROUND OF THE INVENTION
Non-steroidal anti-inflammatory drugs (NSAIDs) are among the most widely used drugs, probably due to their therapeutic properties as anti-inflammatories, analgesics, anti-pyretics, and anti-thrombolics and are used to treat a variety of clinical conditions manifesting such symptoms as pain, inflammation, fever, and to treat and prevent atherosclerosis.
While these drugs are highly effective, oral administration of many NSAIDs can cause serious adverse effects such as gastrointestinal bleeding and ulceration, liver and kidney damages, and central nervous system and cutaneous disturbances, particularly after extended use. Therefore, in an effort to minimize the adverse effects associated with oral administration, non-oral delivery of NSAIDs has been extensively investigated in recent years.
Transdermal delivery, in particular, is an attractive option because it avoids the hepatic first-pass metabolism, reduces the side effects associated with oral administration, is associated with higher patient compliance and, in some cases, enhances therapeutic efficacy of the drug.
Transdermal delivery of NSAIDs is particularly useful for treatment of rheumatoid arthritis and related conditions, which are characterized by painful and swollen joints due to inflammation in the musculoskeletal tissues of the joints. However, although topical administration of certain NSAIDs has been shown to deliver the drug to the local musculoskeletal tissues of joints where arthritic conditions often develop, due to the low solubility of NSAIDs in water, the effectiveness of topical administration of NSAIDs is limited by the inability of these drugs to permeate the skin.
NSAIDs are weak acid. There are roughly nine major classes of NSAIDs, which are salicylate derivatives (such as acetosalicylate [aspirin]), propionic acid derivatives (such as ibuprofen), aniline derivatives (such as aminophenolacetaminophen [tylenol]), pyrazole derivatives (such as phenylbutazone), N-arylanthranilic acid (or fenamates) derivatives (such as meclofenamate), indole derivatives (such as indomethacin), acetic acid derivatives (such as diclofenac), oxicam derivatives (such as piroxicam), and miscellaneous others (such as celecoxib).
Among the NSAIDs, diclofenac, which is 2-(2,6-dichloro-anilino)-phenyl-acetic acid, is particularly known for its role as an anti-rheumatic agent for treatment of rheumatoid arthritis. Diclofenac belongs to the acetic acid class of NSAID. Due to its relatively low solubility in water, an aqueous injection solution of diclofenac is difficult to achieve.
U.S. Pat. No. 4,711,906 discloses a liquid diclofenac preparation where a better dissolution of the diclofenac is obtained when a local anesthetic, lidocaine, is added. This liquid diclofenac preparation is particularly suitable for use as injection solution.
Another NSAID similar to diclofenac and also belongs to the acetic acid class of NSAIDs is ketorolac. Ketorolac is comparable to opioids in terms of providing pain relief. For example, the overall analgesic effect of 30 mg of ketorolac is equivalent to that of 6 to 12 mg of Morphine.
Ketorolac is (±)-5-benzoyl-2,3-dihydro-1H-pyrrolizine-1-carboxylic acid. It is a derivative of pyrrolizine carboxylic acid and is structurally related to tolmetin and zomepirac. Like diclofenac, the free acid form of ketorolac has very low solubility in water. The most commonly used salt form of ketorolac is ketorolac tromethamine, which is much more water soluble than the free acid form of ketorolac.
Although NSAIDs are widely used as anti-inflammatories and analgesics, the use of NSAIDs in alleviating symptoms associated with herpes virus infection is largely unexplored. Herpetic infections are highly contagious skin eruptions or lesions, characterized by a cluster of small blisters or watery vesicles. The lesions are caused by an acute viral infection. The virus is from the genus Herpesvirus.
The herpesviruses comprise a large family of double stranded DNA viruses. The herpesvirus family can be divided into three subfamilies (i.e., α, β, and γ) based upon a number of biological properties such as host range and tropism, viral life cycle, and viral persistence and latency. Eight of the herpesviruses, herpes simplex virus types 1 and 2 (HSV-1 and HSV-2), varicella zoster virus (VZV), human cytomegalovirus (HCMV), Epstein-Barr virus (EBV), and human herpes viruses 6, 7, and 8 (HHV-6, HHV-7, and HHV-8), have been shown to infect humans.
Among the herpesviruses, the two commonly known viruses are herpes simplex virus types 1 and 2, referred to as HSV1 and HSV2 and varicella-zoster virus (VZV). HSV1 causes orofacial lesions, commonly known as fever blisters or cold sores. These lesions most commonly appear on the lips, but may appear on the face, in the mucous membrane lining of the oral cavity, in the eye and nose, and occasionally on the trunk of hands. Infections of the mouth are designated with the term herpes labialis, also called cold sore (feverblister). Other parts of the face can also be affected and the infections thereof are referred to as facial herpes simplex. The infection can also manifest itself on other parts of the body. Approximately 30% of the United States population suffer from recurrent episodes of HSV1. HSV2, which is less common than HSV1, causes genital lesions. Conversely, genital herpes is caused in about 30% of cases by HSV1.
Varicella-zoster virus (VZV) causes varicella, commonly known as chicken pox, and herpes zoster, commonly known as shingles. Shingles affects the skin and nerves and is characterized by groups of small blisters or lesions appearing along certain nerve segments. The lesions are most often seen on the back and may be preceded by a dull ache in the affected site.
Once an individual has been infected with the herpes virus, the virus will thereafter remain latently in the body. In latent state, the virus is situated in nerve cell bodies in the ganglia. Due to particular stimuli, such as influenza infection, other respiratory disorders, gastrointestinal infections, stress, fatigue, menstruation, pregnancy, allergy, sunlight, or fever, the latent virus can be activated and travel from the ganglia along the well-defined nerve paths to the skin surface and there multiply and cause the symptoms.
There is no treatment known to kill the herpes virus at this time. Most of the available treatments can only help to accelerate the healing of the lesions and the associated symptoms, but have not been shown to be efficacious in the treatment of herpes virus infections.
The best known treatment for herpes virus infections at this time is probably Zovirax.RTM. Ointment (Glaxo Wellcome), which contains the active ingredient acyclovir. Acyclovir, 9-(2-hydroxyethoxymethyl), is a purine nucleoside analogue targeting viral encoded DNA polymerase. Other purine nucleoside analogues which are commercially available for treating herpes virus infections include ganciclovir (Roche) and foscarnet (Astra). Although effective, these purine nucleoside analogues are poorly soluble in water and demonstrate low bioavailability. These, accompanying the relative long recovery time required (i.e., generally takes longer than 2 weeks for patients to recover) and high prescription cost, make the drugs less attractive to the patients.
Other commonly known anti-viral drugs for treatment of herpes virus include foscarnet (U.S. Pat. No. 4,215,113); stannous salt, such as stannous fluroide (U.S. Pat. No. 5,098,716); and sulphated polysaccharides, such as dextran sulphate and pentosan polysulphate. Recently, U.S. Pat. No. RE37,727 discloses a method for treating nerves injury pain associated with shingles by using a local anethetic agent, lidocaine.
NSAIDs are not widely known for treatment of viruses, notwithstanding herpes viruses. U.S. Pat. Nos. 4,473,584 and 4,477,468 disclose a process for treating HSV1 and HSV2 infection by systemic administration or topical application of flurbiprofen (3-fluoro-4-phenylhydratropic acid) or a salt or ester thereof. U.S. Pat. No. 5,514,667 discloses a topical preparation for treating herpes virus infections which combines an anti-viral drug, such as foscarnet, suramin, polysulphated polysaccharides, polysulphated polymers, purine nucleoside analogues, with a potentiating drug which can be an NSAID. U.S. Pat. No. 5,747,070 discloses a treatment for herpes infections which combines stannous salt with another therapeutic agent, such as an NSAID.
The present invention provides a topical formulation containing an NSAID, preferably diclofenac, to provide fast and effective treatment for alleviating symptoms relating to HSV and VZV infections, including inflammation and/or pain caused by HSV and VZV infections. In comparing with the topical treatment by acyclovir, the topical formulation of the present invention reduces the recovery time from about two (2) weeks when acyclovir is applied, to about one (1) week when a topical preparation using the topical formulation of the present invention is applied.
SUMMARY OF THE INVENTION
The present invention provides a topical formulation containing diclofenac, including, without limitation, diclofenac acid, diclofenac sodium, diclofenac potassium, diclofenac diethylamine, diclofenac triethanolamine, and diclofenac tromethamine. The topical formulation is especially used for treatment with pain and/or inflammation associated with infection caused by herpes virus, including, but not limited to, herpes simplex virus (HSV) and/or varicella-zoster virus (VZV). Also, the topical formulation does not contain an anti-viral drug. Optionally, the topical formulation may or may not contain a local anesthetic agent. Examples of an anti-viral drug includes purine nucleoside analogues (e.g., acyclovir, valacyclovir, and ganciclovir); foscarnet; suramin; stannous salt, such as stannous fluroide; and sulphated polysaccharides, such as dextran sulphate and pentosan polysulphate.
The topical formulation is preferably delivered as a liquid or semi-liquid topical preparation. Examples of the topical preparation include, without limitation, solution, suspension, gel, emugel, cream, ointment, lotion, and transdermal patch.
The preferred amount of diclofenac used in the topical formulation is about 0.1–10% by weight (w/w) or by volume (w/v) of the entire topical formulation.
The topical formulation of the present invention is further characterized by its fast recovery effect (i.e., no more than 7 days) on skin blisters/lesions caused by herpes virus infection.
Optionally, the diclofenac in the topical formulation is replaced with a non-diclofenac non-steroidal anti-inflammatory drug (NSAID), which includes, without limitation, etodolac, ketorolac, bromfenac, diflunisal, ibuprofen, fenoprofen, ketoprofen, naproxen, suprofen, meclofenamate, mefenamic acid, piroxicam, meloxicam, indomethacin, sulindac, phenylbutazone, oxyphenbutazone, and tolmetin. The preferred NSAID is ketorolac, such as a free acid form of ketorolac or ketorolac tromethamine.
The present invention also provides a method for treating patients with pain and/or inflammation associated with infection caused by herpes virus, such as herpes simplex virus (HSV) and/or varicella-zoster virus (VZV). The method includes topically applying to the patients an effective amount of the topical formulation containing diclofenac, including, without limitation, diclofenac acid, diclofenac sodium, diclofenac potassium, diclofenac diethylamine, diclofenac triethanolamine, and diclofenac tromethamine. The topical formulation does not contain an anti-viral drug. Optionally, the topical formulation may or may not contain a local anesthetic agent. The effective amount of the diclofenac is about 0.1˜10% by weight (w/w) or by volume (w/v) of the entire topical formulation. The topical formulation of the present invention, when applies to patients with skin blisters/lesions caused by herpes virus infection, fasten the skin recovery to no more than 7 days.
Optionally, the diclofenac is replaced with a non-diclofenac non-steroidal anti-inflammatory drug (NSAID), such as etodolac, ketorolac, bromfenac, diflunisal, ibuprofen, fenoprofen, ketoprofen, naproxen, suprofen, meclofenamate, mefenamic acid, piroxicam, meloxicam, indomethacin, sulindac, phenylbutazone, oxyphenbutazone, and tolmetin. The preferred NSAID is ketorolac, such as a free acid form of ketorolac or ketorolac tromethamine.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 shows the results of patients infected with herpes viruses after being topically treated with the topical formulation of the present invention in the form of a gel for seven (7) days. represents the period of time (days) when a scab was formed. ▮ represents the period of time (days) when the scab is automatically peeled off from the skin, an indication that the lesions were cured.
DETAILED DESCRIPTION OF THE INVENTION
The topical formulation of the present invention has been examined by the following instrumentations to ensure quality:
High Performance Liquid Chromatography (HPLC): The topical formulation can be characterized and purified by HPLC. Alternatively, the content or purity of the topical formulation can be determined by HPLC. For a given column packing, solvent system, and flow rate, the composition tends to elute to a certain degree from an analytical or preparative HPLC column.
UV Spectroscopy: the UV spectroscopy can be used to perform qualitative analysis of the topical formulation.
Transdermal Absorption Test: the transdermal absorption of the topical formulation can be determined using the transdermal diffusion measurement instrument. For example, the accumulative transdermal absorption is determined by 3M 9728 Membranes.
pH Determination: pH of the topical formulation is determined by a pH-meter.
The topical formulations used in the present invention are particularly suitable for formulations as topical preparations. Formulations suitable for topical administration include liquid or semi-liquid preparations suitable for penetration through the skin to the site of where treatment is required. Examples of liquid and semi-liquid preparations include, but are not limited to, topical solutions, liniments, lotions, creams, ointment or paste, gel, and emugel. Other topical ingredients used in the topical formulation are in general those commonly used and generally recognized by person skilled in the art of topical formulation.
Topical solution of the present invention may contain aqueous or oily solution or suspensions. They may be prepared by dissolving the pharmaceutical compound in a suitable aqueous solution which may also contain a bactericidal agent, a fungicidal agent, or any other suitable preservative, and may preferably include a surface active agent. Suitable solvents for the preparation of an oily solution include glycerol, diluted alcohol, and propylene glycol. Optionally, L-menthol may be added to the topical solution.
Lotions and liniments include those suitable for application to the skin containing a sterile aqueous solution and optionally, a bactericide. They may also include an agent to hasten drying and cooling of the solution on the skin, such as alcohol or acetone. They may further include a moisturizer, such as glycerol, or an oil, such as castor oil or arachis oil.
Cream, ointments, or pastes, are semi-solid formulations made by mixing the pharmaceutical with a greasy or non-greasy base. The topical formulation is in finely-divided or powdered form and may be alone or in a aqueous or non-aqueous solution or suspension. The topical formulation may be mixed with the greasy or non-greasy base with the aid of suitable machinery. The base may contain hydrocarbons. Examples of the hydrocarbons include, but are not limited to, hard, soft, or liquid paraffin, glycerol, beeswax, a metallic soap, a mucilage, an oil of natural origin (such as almond, corn, arachis, castor or olive oil), wool fat or its derivative, a fatty acid (such as stearic acid or oleic acid), or a combination thereof. The formulation may also contain a surface active agent, such as an anionic, cationic or non-ionic surfactant. Examples of the surfactants include, but are not limited to, sorbitan esters or polyoxyethylene derivatives thereof (such as polyoxyethylene fatty acid esters) and carboxypolymethylene derivatives thereof (such as carbopol). Suspending agents such as natural gums, cellulose derivatives inorganic materials such as silicaceous silicas, and other ingredients such as lanolin, may also be included. For ointment, polyethylene glycol 540, polyethylene glycol 3350, and propylene glycol may also be used to mixed with the topical formulation.
A gel or emugel formulation includes any gel forming agent commonly used in the pharmaceutical gel formulations. Examples of gel forming agents are cellulose derivatives such as methyl cellulose, hydroxyethyl cellulose, and carboxymethyl cellulose; vinyl polymers such as polyvinyl alcohols, polyvinyl pyrrolidones; carboxypoly-methylene derivatives such as carbopol. Further gelling agents that can be used for the present invention are pectins and gums (such as gum arabic and tragacanth, alginates, carrageenates, agar and gelatin). The preferred gelling agent is carbopol. Furthermore, the gel or emugel formulation may contain auxiliary agents commonly used in the kind of formulations such as preservatives, antioxidants, stabilizers, colorants, and perfumes.
The following examples are illustrative, but not limiting the scope of the present invention. Reasonable variations, such as those occur to reasonable artisan, can be made herein without departing from the scope of the present invention.
EXAMPLE 1
Preparation of A Gel Containing Diclofenac Acid
A gel containing diclofenac acid for topical treatment of pain/inflammation caused by HSV and/or VZV infection was prepared as follows:
Ingredients
Weight (g)
Diclofenac Acid
10
L-Menthol
10
Propylene glycol
200
Triethanolamine
20
Carboxypolymethylene (Carbopol)
15
Isopropyl Alcohol
250
Purified Water
375
Total Weight
880
The method for preparing the gel was as follows:
1. Carbopol 15 g was mixed with isopropyl alcohol 150 g. Then, purified water 375 g was added to the mixture and mixed well so that Carbopol and isopropyl alcohol dissolved in the purified water.
2. Diclofenac acid 10 g, propylene glycol 200 g, and isopropyl alcohol 50 g were mixed together and dissolved.
3. L-menthol 10 g was added to isopropyl alcohol 50 g and mixed so that L-menthol dissolved in the isopropyl alcohol.
4. Mixtures obtained from steps 2 and 3 were added to the mixture from step 1 and mixed until they were evenly distributed. Then, triethanolamine 20 g was added to the mixture and mixed well to obtain the topical formulation to be used in the present invention in the form of a gel.
EXAMPLE 2
Preparation of A Gel Containing Diclofenac Acid
A gel containing diclofenac acid for topical treatment of pain/inflammation caused by HSV and/or VZV infection was prepared from the following ingredients:
Ingredients
Weight (g)
Diclofenac Acid
296.15
L-Menthol
200
Propylene Glycol
4000
Triethanolamine
400
Carboxypolymethylene (Carbopol)
200
Isopropyl Alcohol
6900
Purified Water
7669.51
Total Weight
19665.66
The topical formulation was prepared as follows:
1. Carbopol 200 g was mixed with isopropyl alcohol 150 g. Then, purified water 7669.51 g was added to the mixture and mixed well so that Carbopol and isopropyl alcohol dissolved in the purified water.
2. Diclofenac acid 296.15 g, propylene glycol 4000 g, and isopropyl alcohol 50 g were mixed together and dissolved.
3. L-menthol 200 g was added to isopropyl alcohol 50 g and mixed so that L-menthol dissolved in the isopropyl alcohol.
4. Mixtures obtained from steps 2 and 3 were added to the mixture from step 1 and mixed until they were evenly distributed. Then, triethanolamine 400 g was added to the mixture and mixed well to obtain the topical formulation to be used in the present invention in the dosage form of a gel.
EXAMPLE 3
Preparation of A Solution Containing Diclofenac Acid
A solution containing diclofenac acid was prepared from the following ingredients:
Ingredients
Weight (g) or Volume (ml)
Diclofenac Acid
29.615
g
L-Menthol
2
g
Alcohol
5280
ml
Purified Water
2830
ml
Total Weight
8000
ml
The solution of the present invention was prepared as follows:
1. Diclofenac acid 29.615 g was added to alcohol 4000 g, mixed together, and dissolved.
2. L-menthol 2 g was added to the mixture from step 1 and mixed until dissolved. Purified water was added to and mixed with the mixture to make up a total volume of 8000 ml to obtain the topical formulation to be used in the present invention in the dosage form of a solution.
EXAMPLE 4
Preparation of A Cream Containing Diclofenac Acid
A cream containing diclofenac acid to be used in the present invention was prepared from the following ingredients:
Ingredients
Weight (g) or Volume (ml)
Diclofenac acid
29.615
g
Alcohol
200
ml
Polyoxyethylene Fatty Acid Esters
200
g
Carboxypolymethylene (Carbopol)
50
g
Purified Water
720.385
g
Total Weight
1000
g
The cream was prepared as follows:
1. Diclofenac acid 29.615 g was added to alcohol 200 ml and mixed together so that diclofenac acid was dissolved.
2. The mixture from step 1 was added to and mixed with polyoxyethylene fatty acid esters. The mixture was heated and mixed until dissolved.
3. Carbopol 50 g was added to and mixed with purified water 500 g to obtain a homogeneous solution.
4. The mixtures from steps 2 and 3 were mixed evenly and added to purified water 220.385 g. Then, the mixture was stirred until dissolved evenly to obtain the topical formulation to be used in the present invention in the dosage form of a cream.
EXAMPLE 5
Preparation of An Ointment Containing Diclofenac Acid
An ointment containing diclofenac acid was prepared from the following ingredients:
Ingredients
Weight (g) or Volume (ml)
Diclofenac acid
23.434
g
Alcohol
200
ml
Polyethylene Glycol 540
200
g
Polyethylene Glycol 3350
646.951
g
Propylene Glycol
139.615
g
Total Weight
1000
g
The ointment was prepared as follows:
1. Diclofenac acid 23.434 g was added to alcohol 200 ml and mixed until diclofenac was dissolved and evenly distributed.
2. The mixture from step 1 was added to polyethylene glycol 540 and polyethylene glycol 3350 and heated until the mixture was completely dissolved.
3. The mixture from step 2 was added with propylene glycol and mixed till dissolved evenly to obtain the topical formulation to be used in the present invention in the dosage form of an ointment.
EXAMPLE 6
Preparation of An Emugel Containing Diclofenac Diethylamine
An emugel containing diclofenac diethylamine to be used in the present invention was prepared from the following ingredients:
Ingredients
Weight (g)
Diclofenac Acid Diethylamine Salt
11.6
L-Menthol
10
Propylene Glycol
200
Triethanolamine
20
Carboxypolymethylene (Carbopol)
15
Isopropyl Alcohol
150
Purified Water
343.4
The emugel of the present invention was prepared as follows:
1. Diclofenac acid diethylamine salt and propylene glycol were added to purified water 200 g and mixed until they were dissolved and evenly distributed.
2. Carbopol was added to and mixed with isopropyl alcohol 100 g until even distribution. Purified water 143.4 g was added to and mixed with the mixture to dissolve evenly.
3. L-Menthol was added to and mixed with isopropyl alcohol 50 g until evenly dissolved.
4. Mixtures from steps 1, 2, and 3 were added together, mixed, until evenly distributed. Triethanolamine was added and mixed with the mixture to obtain the topical formulation to be used in the present invention in the dosage form of an emugel.
EXAMPLE 7
Preparation of A Gel Containing Diclofenac Sodium
A gel containing diclofenac sodium was prepared from the following ingredients:
Ingredients
Weight (g)
Diclofenac Sodium
10
L-Menthol
10
Propylene Glycol
200
Triethanolamine
20
Carboxypolymethylene (Carbopol)
15
Isopropyl Alcohol
250
Purified Water
375
Total Weight
880
The gel was prepared as follows:
1. Carbopol was added with isopropyl alcohol 150 g and mixed to dissolve evenly. Purified water was added to and mixed with the mixture to dissolve evenly.
2. Diclofenac sodium, propylene glycol, and isopropyl alcohol 50 g were mixed to dissolve.
3. L-Menthol was added with isopropyl alcohol 50 g and mixed to dissolve evenly.
4. Mixtures from steps 2, and 3 were mixed and added to the mixture from step 1 and evenly distributed. Triethanolamine was added to and mixed with the mixture to obtain the topical formulation to be used in the present invention in the dosage form of a gel.
EXAMPLE 8
Preparation of A Lotion Containing Diclofenac Acid
A lotion containing diclofenac acid was prepared from the following ingredients:
Ingredients
Weight (g) or Volume (ml)
Diclofenac Acid
29.615
g
Alcohol
120
ml
White soft paraffin
7.6
g
Cetyl Alcohol
19
g
Propylene Glycol
57
g
Methyl Paraben
1.5
g
Propyl Paraben
0.5
g
Sodium Lauryl Sulfate
3
g
Purified Water add to
1000
g
The lotion was prepared as follows:
1. Diclofenac acid 29.615 g was dissolved in 120 ml of alcohol.
2. Methyl paraben, propyl paraben, and sodium lauryl sulfate were dissolved in 300 ml of purified water and mixed and heated at about 60° C. until they were dissolved.
3. White soft paraffin, cetyl alcohol, and propylene glycol were heated until completely dissolved.
4. The mixtures from steps 1 and 3 were mixed evenly, then, the mixture from step 2 was added to the mixture to mix evenly. Finally, purified water was added to bring the total weight to 1000 g and mixed evenly to obtain the topical formulation to be used in the present invention in the dosage form of a lotion.
EXAMPLE 9
Preparation of A Gel Containing Diclofenac Sodium
The gel containing diclofenac sodium was prepared from the following ingredients:
Ingredients
Weight (g)
Diclofenac Sodium
29.615
L-Menthol
20
Propylene glycol
400
Triethanolamine
40
Carboxypolymethylene (Carbopol)
20
Isopropyl Alcohol
690
Purified Water
766.9
Total Weight
1966.515
The gel of the present invention was prepared as follows:
1. Carbopol was added with isopropyl alcohol 50 g and mixed to dissolve evenly. Purified water was added to and mixed with the mixture to dissolve evenly.
2. Diclofenac sodium, propylene glycol, and isopropyl alcohol 20 g were mixed until dissolved.
3. L-Menthol was added to and mixed with isopropyl alcohol 50 g until dissolved evenly.
4. Mixtures from steps 2, and 3 were mixed and added to the mixture from step 1 until distributed evenly. Triethanolamine was added to and mixed with the mixture to obtain the topical formulation to be used in the present invention in the dosage form of a gel.
EXAMPLE 10
Preparation of A Gel Containing Ketorolac Acid
A gel containing ketorolac acid was prepared from the following ingredients:
Ingredients
Weight (g)
Ketorolac Acid
10
L-Menthol
10
Propylene Glycol
200
Triethanolamine
20
Carboxypolymethylene (Carbopol)
15
Isopropyl Alcohol
250
Purified Water
375
Total Weight
880
The gel was prepared as follows:
1. Carbopol was added to isopropyl alcohol 150 g until dissolved evenly. Purified water was then added to and mixed with the carbopol-isopropyl alcohol mixture until dissolved evenly.
2. Ketorolac acid, propylene glycol, and isopropyl alcohol 50 g were thoroughly mixed until dissolved evenly.
3. L-Menthol was added to isopropyl alcohol 50 g and mixed until dissolved evenly.
4. Mixtures from steps 2, and 3 were mixed and added to the mixture from step 1 until even distribution. Triethanolamine was added to and mixed with the mixture to obtain the topical formulation to be used in the present invention in the dosage form of a gel.
EXAMPLE 11
Preparation of An Emugel Containing Diclofenac Potassium
An emugel containing diclofenac potassium was prepared from the following ingredients:
Ingredients
Weight (g)
Diclofenac Potassium
11.6
L-Menthol
10
Propylene Glycol
200
Triethanolamine
20
Carboxypolymethylene (Carbopol)
15
Isopropyl Alcohol
150
Purified Water
343.4
The topical formulation was prepared as follows:
1. Diclofenac potassium and propylene glycol were added to purified water 200 g and mixed until they were dissolved and evenly distributed.
2. Carbopol was added to and mixed with isopropyl alcohol 100 g until dissolved evenly. Purified water 143.4 g was added to and mixed with the mixture until dissolved evenly.
3. L-Menthol was added to and mixed with isopropyl alcohol 50 g until dissolved evenly.
4. Mixtures from steps 1, 2, and 3 were mixed together until evenly distributed. Triethanolamine was added to and mixed with the mixture to obtain the topical formulation to be used in the present invention in the dosage form of a cream.
EXAMPLE 12
Preparation of A Cream Containing Diclofenac Potassium
A cream containing diclofenac potassium was prepared from the following ingredients:
Ingredients
Weight (g) or Volume (ml)
Diclofenac Potassium
29.615
g
Alcohol
200
ml
Polyoxyethylene Fatty Acid Esters
200
g
Carboxypolymethylene (Carbopol)
50
g
Purified Water
720.385
g
Total Weight
1000
g
The cream of the present invention was prepared as follows:
1. Diclofenac potassium was added to alcohol 200 ml and mixed together until diclofenac potassium was dissolved.
2. The mixture from step 1 was added to and mixed with polyoxyethylene fatty acid esters. The mixture was heated while mixing until complete dissolution.
3. Carbopol was added to and mixed with purified water 500 g to obtain a homogeneous solution.
4. The mixtures from steps 2 and 3 were mixed evenly and added to purified water 220.385 g. Then, the mixture was stirred until dissolved evenly to obtain the topical formulation to be used in the present invention in the dosage form of a cream.
EXAMPLE 13
Preparation of A Solution Containing Ketorolac Tromethamine
A solution containing ketorolac tromethamine was prepared from the following ingredients:
Ingredients
Weight (g) or Volume (ml)
Ketorolac Tromethamine
30
g
L-Menthol
0.5
g
Alcohol
760
ml
Purified Water
280
ml
Total Weight
1000
ml
The solution was prepared as follows:
1. Ketorolac tromethamine was added to purified water 150 ml and mixed until complete dissolution.
2. L-menthol was added to alcohol and mixed until dissolved. Then, the mixture from step 1 was added to the L-menthol solution and mixed until dissolved. Purified water was added to the mixture to make up a total volume of 1000 ml to obtain the topical formulation to be used in the present invention in the dosage form of a solution.
EXAMPLE 14
Preparation of A Cream Containing Ketorolac Tromethamine
A cream containing ketorolac tromethamine to be used in the present invention was prepared from the following ingredients:
Ingredients
Weight (g) or Volume (ml)
Ketorolac Tromethamine
50
g
Alcohol
200
ml
Polyoxyethylene Fatty Acid Esters
200
g
Carboxypolymethylene (Carbopol)
50
g
Purified Water
750
g
Total Weight
1000
g
The cream was prepared as follows:
1. Ketorolac tromethamine was added to and mixed with purified water 300 ml until dissolution.
2. The mixture from step 1 was added to and mixed with polyoxyethylene fatty acid esters. The mixture was heated while mixing until complete dissolution.
3. Carbopol was added to and mixed with purified water 450 ml to obtain a homogeneous solution.
4. The mixtures from steps 2 and 3 were mixed evenly and added to alcohol. Then, the mixture was stirred until dissolved evenly to obtain the topical formulation to be used in the present invention in the dosage form of a cream.
The following are illustrations of clinical studies using the topical formulation (i.e., a gel) of the present invention as specified in Example 1 above on patients with herpes virus infection. The patients participated in these studies all developed small blisters or lesions on or surrounding the lips due to the infection. Other topical formulations, as demonstrated above, showed similar effects as those described below.
CLINICAL TREATMENT EXAMPLE 1
A male patient A with herpetic infection on the lips was treated topically with the gel of the present invention. The gel had immediate effects on relieving pain and itching caused by the infection. About one week later, scabs were formed and peeled off, with areas of skin returned to normal.
CLINICAL TREATMENT EXAMPLE 2
A female patient B with herpetic infection on the lower lip area, as shown by lesions/blisters, was treated topically with the gel of the present invention. The gel had immediate effects on relieving pain and itching from the patient. On the second day after the application of the gel, the lesions/ blisters started to shrink and gradually healed. On the third day, the lesions/blisters began to form scabs. On the fifth day, the scabs began to peel off automatically and the skins showed complete recovery shortly thereafter.
CLINICAL TREATMENT EXAMPLE 3
A female patient C with herpetic infection on the upper lip area, as shown by lesions/blisters, was treated topically with the gel of the present invention. The gel had immediate effects on relieving pain and itching from the patient. On the third day, the lesions/blisters were completely disappeared.
CLINICAL TREATMENT EXAMPLE 4
A male patient D with herpetic infection on the upper lip area, as shown by lesions/blisters, was treated topically with the gel of the present invention. The gel had immediate effect on relieving pain from the patient. On the third day, the lesions/blisters began to form scabs. On the seventh day, the scabs automatically peeled off and the areas of skin were returned to normal.
CLINICAL TREATMENT EXAMPLE 5
A male patient E, with herpetic infection at the corners of the lips by forming lesions/blisters, was treated topically with the gel of the present invention. The gel had immediate effect on relieving pain from the patient. On the second day, the lesions/blisters were completely disappeared.
CLINICAL TREATMENT EXAMPLE 6
A male patient F with herpetic infection on the upper lip area, as shown by lesions/blisters, was treated topically with the gel of the present invention. The gel had immediate soothing effect and relieving pain from the patient. On the third day, the lesions/blisters began to form scabs. On the fifth day, the scabs automatically peeled off, and the lesions/blisters were completely disappeared.
CLINICAL TREATMENT EXAMPLE 7
A male patient G with herpetic infection on the facial skin between the lips and the nose, as shown by lesions/blisters, was treated topically with the gel of the present invention. The gel had immediate soothing effect and relieving pain from the patient. On the second day, the lesions/blisters began to form scabs. On the sixth day, the lesions/blisters were completely disappeared.
The clinical application of the gel of the present invention to patients with herpes virus infection was summarized in Table 1 and FIG. 1 :
TABLE 1
Treatment Effects on Patients with Herpes Infection
Example
Sex
Affected Area
Treatment Effect
A
male
herpetic infection on
significant effect on relieving pain and
the lips and the
itching; epidermis completely healed
mouth
within about one week.
B
female
herpetic infection on
significant effect on relieving pain and
the lower lip
itching; lesions/blisters formed scabs at
the third day and healed at the fifth day.
C
female
herpetic infection on
significant effect on relieving pain and
the upper lip
itching; healed after about 3 days.
D
male
herpetic infection on
significant effect on relieving pain;
the upper lip
lesions/blisters formed scabs at the third
day and healed after about seven days.
E
male
herpetic infection at
significant effect on relieving pain and
the corners of the lips
itching; healed at about two days.
F
male
herpetic infection on
significant effect on relieving pain;
the upper lip
lesions/blisters formed scabs at the third
day and healed at about five days.
G
male
skin between the lips
significant effect on relieving pain;
and the nose
lesions/blisters formed scabs at the
second day and healed at about six days.
While the invention has been described by way of examples and in terms of the preferred embodiments, it is to be understood that the invention is not limited to the disclosed embodiments. On the contrary, it is intended to cover various modifications as would be apparent to those skilled in the art. Therefore, the scope of the appended claims should be accorded the broadest interpretation so as to encompass all such modifications. | The present invention provides a topical formulation containing NSAID, particularly diclofenac. The topical formulation is particularly useful for alleviating pain/inflammation associated with infection caused by herpes virus, especially herpes simplex virus (HSV) and varicella-zoster virus (VZV). Similar relief can be achieved where diclofenac is replaced with another non-steroidal anti-inflammatory drug (NSAID), which includes, without limitation, etodolac, ketorolac, bromfenac, diflunisal, ibuprofen, fenoprofen, ketoprofen, naproxen, suprofen, meclofenamate, mefenamic acid, piroxicam, meloxicam, indomethacin, sulindac, phenylbutazone, oxyphenbutazone, and tolmetin. The topical formulation is further characterized by its fast relief on pain and/or inflammation associated with infection caused by herpes virus, i.e., a complete relief in no more than seven (7) days after the application of the topical formulation on skins of patients. | 8 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation of U.S. patent application Ser. No. 14/237,694, filed Aug. 9, 2012, which is the United States national phase of International Application No. PCT/JP2012/070310 filed Aug. 9, 2012, and claims priority to Japanese Patent Application No. 2011-175403 filed Aug. 10, 2011, the disclosures of which are hereby incorporated in their entirety by reference.
The Sequence Listing associated with this application is filed in electronic format via EFS-Web and is hereby incorporated by reference into the specification in its entirety. The name of the text file containing the Sequence Listing is SequenceListing.txt. The size of the text file is 17,419 bytes and the text file was created on Jan. 28, 2014.
BACKGROUND OF THE INVENTION
Field of the Invention
The present invention relates to a bilirubin excretion enhancer. More specifically, the present invention relates to a bilirubin excretion enhancer with a serum albumin domain II-like protein, containing the subdomain IIA of serum albumin, as an active ingredient.
Description of Related Art
Bilirubin is a final product of the degradation of a heme which is a component of a red blood cell. Within various isomers thereof, the isomer that exists most abundantly in the body is 4Z, 15Z-bilirubin-IXα (hereinafter, referred to as 4Z, 15Z-BR). A newborn is susceptible to hyperbilirubinemia and jaundice because of the immaturity of liver, which is a 4Z, 15Z-BR metabolizing tissue. If the level of bilirubin becomes high, bilirubin may deposit on cranial nerves, thereby causing encephalopathy. Nowadays, the first-line therapy for jaundice of the newborn is phototherapy. Phototherapy is a therapy in which the skin of a newborn is irradiated with light to convert 4Z, 15Z-BR having a low water solubility to an isomer having a high water solubility such as 4Z, 15E-bilirubin-IXα (4Z, 15E-BR) or Z-lumirubin, and promote the excretion of bilirubin into urine and bile. The mechanism for bilirubin phototherapy is shown in FIG. 1 . However, although phototherapy is effective for bilirubin deposited on the skin, it is not effective for bilirubin in blood because light does not reach bilirubin in blood. Moreover, since the skin of an adult hardly transmits light, phototherapy is performed only on a newborn.
Therefore, at this time, plasma exchange in which plasma in blood is exchanged to lower the bilirubin concentration or adsorption removal of bilirubin using a column for bilirubin adsorption is performed. However, the adsorption removal method involves an increased risk of infectious diseases, and removes proteins and vitamins useful for a living body.
Human serum albumin (hereinafter, referred to as HSA) is the main protein present in adult serum, is produced in the liver, and functions as a carrier transporting various serum molecules. Moreover, bilirubin binds to HSA and is carried to the liver, and then binds to glucuronic acid in the liver to become a conjugated bilirubin that dissolves in water more easily. This conjugated bilirubin is secreted from the liver as bile.
HSA is a single-stranded protein (SEQ ID NO: 10) of 585 amino acids, and the basic structure is composed of three domains (domain I, II and III) having a high homology, each of which is segmented into subdomains (A and B). The domain I ranges amino acid positions 1 to 197, the domain II ranges amino acid positions 187 to 385, and the domain III ranges amino acid positions 381 to 585.
It is reported that the site I (domain II) is a high affinity binding site for bilirubin. The inventors have obtained an albumin variant having a high binding activity with respect to bilirubin, and found that the amino acids at positions 195 and 199 contribute to bilirubin binding (Patent Document 1). Moreover, the inventors have produced a protein including the domain I of HSA by genetic recombination (Patent Document 2).
PRIOR ART DOCUMENTS
Patent Documents
Patent Document 1: Japanese Laid-Open Patent Publication No. 2010-172277
Patent Document 2: Japanese Laid-Open Patent Publication No. 2005-245268
SUMMARY OF THE INVENTION
Problems to be Solved by the Invention
It is an object of the present invention to provide a bilirubin excretion enhancer in order to establish a novel therapeutic method for hyperbilirubinemia.
Means for Solving the Problems
The inventors have intensively studied a method for direct excretion of bilirubin, particularly 4Z,15Z-BR in order to solve the above problems, and found that a serum albumin domain II-like protein including the subdomain IIA of serum albumin binds to bilirubin and the bound bilirubin is excreted to urine. Thus the present invention was accomplished.
The present invention provides a bilirubin excretion enhancer comprising, as an active ingredient, a serum albumin domain II-like protein comprising a serum albumin subdomain IIA.
In one embodiment, the serum albumin subdomain IIA has an amino acid sequence of SEQ ID NO: 1.
In one embodiment, the serum albumin domain II-like protein is a serum albumin domain II.
In one embodiment, the serum albumin domain II has an amino acid sequence of SEQ ID NO: 4.
In one embodiment, the serum albumin domain II-like protein comprises a serum albumin subdomain IB.
In one embodiment, the bilirubin excretion enhancer is a urinary excretion enhancer.
In one embodiment, the bilirubin excretion enhancer is a 4Z, 15Z-bilirubin-IXα excretion enhancer.
Effects of Invention
A serum albumin domain II-like protein as the active ingredient of the bilirubin excretion enhancer of the present invention can bind to bilirubin to allow for rapidly excreting bilirubin into urine. Particularly, it can bind to 4Z, 15Z-BR that has poor water solubility and is not normally excreted into urine, thereby enhancing the renal excretion. Accordingly, it is effective as a bilirubin excretion enhancer and a therapeutic agent of hyperbilirubinemia. Moreover, it can be safely administered to a newborn as well as to an adult, since HSA is present in the body and has excellent safety.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows the mechanism for bilirubin phototherapy.
FIG. 2 is a graph showing the binding ability with respect to 4Z, 15Z-BR for serum albumin domain II-like proteins obtained in Example 1 and Example 2.
FIG. 3 is a graph showing the 4Z, 15Z-BR excretion enhancing effect of a human serum albumin domain II-like protein obtained in Example 1.
FIG. 4 is a graph showing the 4Z, 15Z-BR excretion enhancing effect of a human serum albumin domain II-like protein obtained in Example 1.
DESCRIPTION OF THE INVENTION
A serum albumin subdomain IIA in the present invention refers to a region constituting the subdomain A of the domain II of serum albumin, and a serum albumin fragment of that region.
In the present invention, serum albumin is albumin contained in serum, and may be derived from, for example, humans or other warm-blooded animals (e.g., cattle, monkeys, pigs, horses, sheep, goats, dogs, cats, rabbits, mice, rats, hamsters, guinea pigs, chickens, and quails). In view of the application to pharmaceutical drugs, human serum albumin is preferable.
Wild type human serum albumin (hereinafter, referred to as HSA) has a molecular weight of 66.5 kDa, and the amino acid sequence from positions 1 to 585t of SEQ ID NO: 10 in Sequence Listing. Serum albumin of the present invention includes genetic polymorphisms of HSA and mutants thereof. Up to now, 60 or more types of genetic polymorphisms of HSA are reported. The variant here refers to HSA whose one or more amino acids are deleted, substituted or added.
The serum albumin subdomain IIA of the present invention includes the subdomain IIA of serum albumin, genetic polymorphisms thereof, and mutants thereof. Preferably, it is the subdomain IIA of HSA (hereinafter, referred to as HSA subdomain IIA). The serum albumin subdomain IIA contains a bilirubin binding site.
The HSA subdomain IIA has at least the amino acid sequence of SEQ ID NO: 1 (positions 187 to 248 of SEQ ID NO: 10). More preferably, it has the amino acid sequence of SEQ ID NO: 2 (positions 187 to 295 of SEQ ID NO: 10). Even more preferably, it has the amino acid sequence of SEQ ID NO: 3 (positions 187 to 298 of SEQ ID NO: 10).
The HSA subdomain IIA includes genetic polymorphisms of the HSA subdomain IIA and mutants thereof. The mutant here refers to an HSA subdomain IIA whose one or more amino acids are deleted, substituted or added, and is not limited as long as it has an affinity to bilirubin. Preferably 1 to 20 amino acids, more preferably 1 to 10 amino acids, and even more preferably 1 to 5 amino acids are deleted, substituted or added. Preferable examples of an HSA subdomain IIA mutant include F211R/R218L and F211/R218S/R222W. F211R/R218L is an HSA subdomain IIA mutant in which phenylalanine at the position 211 is substituted with arginine and arginine at the position 218 is substituted with leucine, and F211/R218S/R222W is an HSA subdomain IIA mutant in which phenylalanine at the position 211 is substituted with leucine, arginine at the position 218 is substituted with serine and arginine at the position 222 is substituted with tryptophan.
The HSA subdomain IIA includes proteins having an amino acid sequence different from but substantially identical to that of the subdomain IIA of HSA having the amino acid sequence of Sequence ID No: 1, 2 or 3, and having an affinity to bilirubin equivalent to or more than that of the subdomain IIA of HSA having the amino acid sequence of SEQ ID NO: 1, 2 or 3 so that it can bind to bilirubin to allow for facilitating renal excretion.
In the present invention, the amino acid sequence that is substantially identical to that of the subdomain IIA of HSA having the amino acid sequence of SEQ ID NO: 1, 2 or 3 refers to an amino acid sequence that has preferably approximately 80% or more, more preferably approximately 90% or more, and even more preferably approximately 95% or more homology to the subdomain IIA of HSA having the amino acid sequence of SEQ ID NO: 1, 2 or 3.
Here, “homology” means a ratio (%) of the same amino acid residues and similar amino acid residues to all the overlapping amino acid residues in an optimal alignment of two amino acid sequences determined by using a known mathematical algorithm in the art (preferably, the algorithm may be taken account of the introduction of gaps into one or both of the two sequences for the optimal alignment). “Similar amino acids” refers to amino acids that are similar in physicochemical properties, and examples thereof include amino acids classified into the same group such as aromatic amino acids (Phe, Trp, and Tyr), aliphatic amino acids (Ala, Leu, Ile, and Val), polar amino acids (Gln and Asn), basic amino acid (Lys, Arg, and His), acidic amino acids (Glu and Asp), amino acids having a hydroxyl group (Ser and Thr), or amino acids having a small side chain (Gly, Ala, Ser, Thr, and Met). It is predicted that the substitution with such a similar amino acid does not lead to any change in protein phenotype (i.e., conservative amino acid substitution). Specific examples of conservative amino acid substitution are well known in the art and described in various documents (see, for example, Bowie et al., Science, 247: 1306-1310 (1990)).
A serum albumin domain II-like protein of the present invention is a fragment of serum albumin that contains the serum albumin subdomain IIA, and has a half or less molecular weight of that of serum albumin. Preferably, the molecular weight is one-third or less. A human serum albumin domain II-like protein (hereinafter, referred to as HSA domain II-like protein) is an HSA fragment containing the HSA subdomain IIA, and has a half (33 kDa) or less molecular weight of that of HSA, preferably the molecular weight is one-third (22 kDa) or less.
A serum albumin domain II-like protein of the present invention is a fragment of serum albumin that contains the serum albumin subdomain IIA of the present invention. Preferable serum albumin domain II-like protein is HSA domain II-like protein. HSA domain II-like protein is an HSA fragment containing the HSA subdomain IIA of the present invention. Examples thereof include an HSA fragment composed of the subdomain IIA, an HSA fragment composed of the domain II, an HSA fragment composed of the subdomain IB and the subdomain IIA, an HSA fragment composed of the domain II and the subdomain IB, and an HSA fragment composed of the domain I and the subdomain IIA. Preferably, the serum albumin domain II-like protein of the present invention does not contain the domain III.
The subdomain IIA in serum albumin domain II-like protein may not have the same conformation as that of the subdomain IIA in serum albumin, and may contain any structure in which the subdomain IIA hardly retains the conformation. Also, a region other than the subdomain IIA region of serum albumin domain II-like protein may or may not constitute a domain, and there is no limitation on the positions of the N-terminus and the C-terminus as long as the subdomain IIA region is contained therein.
In one embodiment of a serum albumin domain II-like protein of the present invention, the serum albumin domain IIA is a protein composed of the foregoing serum albumin domain IIA region.
In one embodiment of a serum albumin domain II-like protein of the present invention, the serum albumin domain II includes the domain II of serum albumin, genetic polymorphisms thereof and mutants thereof. Preferably, it is the domain II of HSA (hereinafter, referred to as HSA domain II).
Preferably, the HSA domain II has the amino acid sequence of SEQ ID NO: 4 (positions 187 to 341 of SEQ ID NO: 10). More preferably, it has the amino acid sequence of SEQ ID NO: 5 (positions 187 to 361 of SEQ ID NO: 10). Even more preferably, it has the amino acid sequence of SEQ ID NO: 6 (positions 187 to 385 of SEQ ID NO: 10).
The HSA domain II includes genetic polymorphisms of the HSA domain II and their mutants. The mutant here refers to a HSA domain II whose one or more amino acids are deleted, substituted or added, and is not limited as long as it has the affinity to bilirubin. Preferably 1 to 20 amino acids, more preferably 1 to 10 amino acids, and even more preferably 1 to 5 amino acids are deleted, substituted or added.
The HSA domain II includes a protein that has an amino acid sequence different from but substantially identical to that of the domain II of HSA having the amino acid sequence of SEQ ID NO: 4, 5 or 6, and that has an affinity to bilirubin equivalent to or more than that of the HSA domain II having the amino acid sequence of SEQ ID NO: 4, 5 or 6 so that it can bind to bilirubin to allow for renal excretion.
In the present invention, the amino acid sequence that is substantially identical to that of the domain II of HSA having the amino acid sequence of SEQ ID NO: 4, 5 or 6 refers to an amino acid sequence that has preferably approximately 80% or more, more preferably approximately 90% or more, and even more preferably approximately 95% or more homology to the domain II of HSA having the amino acid sequence of SEQ ID NO: 4, 5 or 6. Homology is as described above.
Serum albumin domain II-like protein of the present invention contains the subdomain IIA region, and may additionally contain the domain I, the subdomain IB or the subdomain IIB. These include genetic polymorphisms thereof and mutants thereof.
In one embodiment of a serum albumin domain II-like protein of the present invention, a protein containing the serum albumin subdomain IB contains the subdomain IB and the subdomain IIA. The protein includes genetic polymorphisms thereof and mutants thereof. Preferably, it is an HSA fragment composed of the HSA domain IB and the HSA subdomain IIA.
Preferably, the HSA fragment composed of the HSA domain IB and the HSA subdomain IIA has the amino acid sequence of SEQ ID NO: 7 (positions 187 to 298 of SEQ ID NO: 10). More preferably, it has the amino acid sequence of SEQ ID NO: 8 (positions 150 to 298 of SEQ ID NO: 10). Even more preferably, it has the amino acid sequence of SEQ ID NO: 9 (positions 124 to 298 of SEQ ID NO: 10).
The HSA fragment composed of the HSA domain IB and the HSA subdomain IIA includes genetic polymorphisms thereof and mutants thereof. The mutant here refers to an HSA fragment composed of the HSA domain IB and the HSA subdomain IIA, whose one or more amino acids are deleted, substituted or added, and is not limited as long as it has the affinity to bilirubin. Preferably 1 to 20 amino acids, more preferably 1 to 10 amino acids, and even more preferably 1 to 5 amino acids are deleted, substituted or added.
The HSA fragment composed of the HSA domain IB and the HSA subdomain IIA includes a protein that has an amino acid sequence different from but substantially identical to that of the HSA fragment having the amino acid sequence of SEQ ID NO: 7, 8 or 9, and that has an affinity to bilirubin equal to or more than that of the HSA fragment having the amino acid sequence of SEQ ID NO: 7, 8 or 9 so that it can bind to bilirubin to allow for renal excretion.
In the present invention, the amino acid sequence that is substantially identical to that of the HSA fragment having the amino acid sequence of SEQ ID NO: 7, 8 or 9 refers to an amino acid sequence that has preferably approximately 80% or more, more preferably approximately 90% or more, and even more preferably approximately 95% or more homology to the HSA fragment having the amino acid sequence of SEQ ID NO: 7, 8 or 9. Homology is as described above.
HSA domain II-like protein as an active ingredient of the bilirubin excretion enhancer of the present invention can be obtained by cleaving HSA obtained from plasma with a reagent such as CNBr and purifying a fragment containing the subdomain IIA. Also, HSA domain II-like protein can be obtained by genetic recombination, for example, by inserting a DNA encoding the protein of interest into an expression vector, is transforming a suitable host with the vector, and culturing the host. For example, HSA domain II-like protein can be produced and purified according to the procedures as described in Japanese Laid-Open Patent Publication Nos. 2010-172277 and 2005-245268.
Bilirubin, of which excretion is enhanced according to the present invention, includes stereoisomers such as 4Z, 15Z-BR and 4Z, 15E-BR, and structural isomers such as Z-lumirubin.
Bilirubin excretion enhancement according to the present invention refers to enhancement of the excretion of bilirubin in the body out of the body to reduce the amount of bilirubin in the body, particularly in blood. Preferably, the excretion of bilirubin into urine is enhanced. More specifically, the conjugate of bilirubin with the HSA domain II-like protein of the present invention is filtered and excreted by the kidney to promote the excretion of bilirubin out of the body.
As the formulation of the bilirubin excretion enhancer of the present invention, tablets, pills, powders, suspensions, capsules, suppositories, injections, ointments, and patches are exemplified. Preferably, it is liquid formulation obtained from purified HSA domain II-like protein or lyophilized formulation obtained by lyophilizing HSA domain II-like protein. A kit formulation may be prepared with lyophilized formulation in combination with dissolving liquid.
A stabilizer such as sugar, sugar alcohol and amino acid, a pH regulator, and a vehicle can be added to the formulation. Also, if necessary, viral inactivating treatment or sterilizing treatment can be performed before or after drug formulation.
There is no limitation on the administration mute of the bilirubin excretion enhancer of the present invention. Examples thereof include transvenous, transarterial, oral, transcutaneous, and transmucosal. The dose and frequency of administration are adjusted while observing the condition of a patient considering the patient's condition, age, sex, body weight, meal, and so on. For example, in the case of injections, a dose of 10-50 mg/bodyweight can be administered once to three times a day. Also, the administration can be once a few days, or only as needed.
Hereinafter, the present invention will be specifically described by way of examples, but the present invention is not limited to the examples.
EXAMPLES
Example 1
HSA donated by The Chemo-Sero-Therapeutic Research Institute was used. Ten milliliters of the solution of CNBr in 70% formic acid solution was added to 30 mg of HSA so that the molar concentration ratio of CNBr to methionine residues in HSA is 200:1, and the mixture was incubated for 24 hours at room temperature in the dark. After that, 40 ml of ion exchanged water was added to the mixture to quench the reaction, and the obtained solution was subjected to centrifugal concentration with Speed vac (registered trademark) plus (Savant Inc.). After buffer was exchange, the sample was purified with HiTrap Blue HP using AKTA Prime plus (GE Healthcare). The column was equilibrated with 20 mM sodium phosphate (pH 7.0), and eluted with gradient of 2 M potassium thiocyanate+20 mM sodium phosphate (pH 7.0). Fractions in which 20 kDa protein was eluted were confirmed by SDS-PAGE, and subjected to the following experiment.
The obtained protein of 20 kDa was confirmed to be HSA domain II-like protein (SEQ ID NO: 9 (Cys124-Met298 of SEQ ID NO: 10)) composed of the domains IB and IIA by non-reducing SDS-PAGE. The resultant HSA domain II-like protein was lyophilized in the usual manner to obtain a lyophilized formulation.
Example 2
According to the procedures described in Japanese Laid-Open Patent Publication No. 2010-172277, HSA domain II gene (SEQ ID NO: 11) was obtained and integrated into the genome of Pichia yeast to produce cells expressing HSA domain II. After that, the yeast was cultured, and HSA domain II was expressed and purified. The purified HSA domain II was confirmed by SDS-PAGE. The resultant HSA domain II-like protein was a protein composed of the domain II, having the amino acid sequence of SEQ ID NO: 6 (positions 187 to 385 of SEQ ID NO: 10), and having a molecular weight of 22 kDa. The resultant HSA domain II-like protein was lyophilized in the usual manner to obtain a lyophilized formulation.
Experimental Example 1
The HSA domain II-like protein obtained in Example 1 (hereinafter, referred to as 20 kDa fragment) and HSA domain II-like protein obtained in Example 2 (hereinafter, also referred to as domain II) were examined for binding ability with respect to 4Z, 15Z-BR.
The concentration of free BR (4Z, 15Z-BR) was measured with improvement of the method of Brodersen (Brodersen et al. J Clin Invest 1974; 54: 1353-64). Two hundred microliters of a mixed solution of 60 μM BR and 30 μM protein was added to a 96 well immunoplate, and was allowed to stand for 20 minutes at 37° C. Ten microliters of 1.75 mM H 2 O 2 was added thereto, and the mixture was allowed to stand for 3 minutes, and 10 μL of 1 μg/mL peroxidase (derived from horseradish) (Sigma) solution was then added to start the reaction. For 10 minutes after the addition, absorbance at 450 nm of each well was measured with an immunoplate reader. A calibration curve was created by plotting the initial oxidation rate and BR concentration, and the concentration of free BR was calculated. The results are shown in FIG. 2 . The binding ability of 20 kDa fragment with respect to 4Z, 15Z-BR was equivalent to that of the domain II.
Experimental Example 2
The 20 kDa fragment was examined on 4Z, 15Z-BR renal excretion enhancing effect. Rats were divided into three groups, each of which consisted of three rats. 4Z,15Z-BR (560 μg/bodyweight) was administered to the rats of the first group (BR group), 4Z,15Z-BR (560 μg/bodyweight) and HSA (62,800 μg/bodyweight) were administered to the rats of the second group (BR-HSA group), and 4Z,15Z-BR (560 μg/bodyweight) and the 20 kDa fragment (18,900 μg/bodyweight) were administered to the rats of the third group (BR-20 kDa group). After 2 hours, blood samples and urine samples were collected, and the concentration of 4Z, 15Z-BR in serum and the concentration of 4Z, 15Z-BR in 0.75-2.25 ml of urine were measured. The concentrations of BR in serum and in urine were measured using QuantiChrom™ Bilirubin Assay Kit (BioAssay Systems). The concentrations of total BR and indirect BR were measured according to the procedure of the kit. The results are shown in FIG. 3 . The concentration of total 4Z, 15Z-BR in serum in the combined administration with the 20 kDa fragment was significantly lowered compared with the combined administration with HSA. Particularly, the concentration of protein bound type 4Z, 15Z-BR was remarkably lowered. The amount of total 4Z, 15Z-BR in urine in the combined administration with the 20 kDa fragment was significantly increased compared with the combined administration with HSA. Moreover, the amount of protein in urine was measured. The results are shown in FIG. 4 . Protein in urine in the combined administration with the 20 kDa fragment was significantly increased compared with the combined administration with HSA. This shows that the 20 kDa fragment was bound to 4Z, 15Z-BR and excreted into urine.
INDUSTRIAL APPLICABILITY
Since the bilirubin excretion enhancer of the present invention binds to bilirubin in the body and is excreted out of the body, it is effective for the excretion and removal of bilirubin in the body, the treatment of hyperbilirubinemia, and so on. | The purpose of the present invention is to establish a novel therapy method for hyperbilirubinemia and therefore, to provide a bilirubin excretion enhancer. The present invention provides a bilirubin excretion enhancer comprising, as an active ingredient, a serum albumin domain II-like protein comprising a serum albumin subdomain IIA. In one embodiment, the serum albumin subdomain IIA has an amino acid sequence of SEQ ID NO: 1. in one embodiment, the serum albumin domain II-like protein is a serum albumin domain II. In one embodiment, the serum albumin domain II comprises the amino acid sequence of SEQ ID NO: 4. | 2 |
TECHNICAL FIELD
This invention relates generally to data communication circuits, and more particularly, to interface circuits for interfacing between the encoding and decoding of data in communication systems.
BACKGROUND ART
Bandwidth of voice frequency signals which exist in eight bit PCM format may be reduced by converting the eight bit PCM signal to a smaller bit ADPCM (adaptive differential pulse code modulation) signal. ADPCM signals may be transmitted over the same transmission lines as PCM signal with existing PCM equipment supplemented by ADPCM encoders and decoders for converting between PCM and ADPCM signals at the ends of the transmission links. The bit size of the ADPCM signal determines the frequency or bandwidth of transmission. I often desirable to modify the bandwidth to accomodate various transmission requirements. Typical ADPCM encoder/decoder circuits are controlled by algorithms which balance and control synchronous bandwidth with quality of voice information being communicated. As a result, a particular algorithm is required by ADPCM encoder/decoder circuits for each particular synchronous bandwidth. When changing between frequencies in ADPCM transmission, the proper algorithm for a frequency must be selected by the encoder/decoder circuit to operate. Previous encoder/decoder circuits have typically used distinct control signals to select the correct algorithm for a predetermined frequency of operation. Additional control signals require additional circuit inputs or I.C. pins to be included in the fabrication and packaging of the encoder/decoder circuit. An algorithm control signal is typically required at both an input terminal which receives eight bit PCM data to be encoded and at an input terminal which receives ADPCM data to be decoded. Therefore, additional packaging inputs are required for an encode/decode circuit.
BRIEF DESCRIPTION OF THE INVENTION
Accordingly, an object of the present invention is to provide an improved ADPCM data interface circuit having an encoded enable signal.
Another object of this invention is to provide an improved ADPCM data interface circuit which minimizes circuitry when selecting algorithmic modes of operation.
Yet another object of the present invention is to provide an improved method for selecting algorithms for use by an encode/decode circuit which interfaces between PCM and ADPCM communication channels.
In carrying out the above and other objects of the present invention, there is provided, in one form, a data interface circuit for interfacing digital data between first and second forms. The data has a first frequency when received and has a second frequency when transmitted. The second frequency has a value which is one of a plurality of predetermined frequency values. The data is encoded or decoded by the interface circuit between frequency values in accordance with one of a plurality of algorithms. A first portion of the interface circuit receives and stores the digital data and outputs the data in frame format at a predetermined clock rate. Frame boundaries of the digital data are controlled by a single control signal. A second portion of the interface circuit receives the data and provides an encoded algorithm signal in response to the same single control signal. The encoded algorithm signal controls which one of the plurality of algorithms that the data is encoded or decoded in accordance with. A third portion of the interface circuit receives and stores both the data in frame format and the encoded algorithm signal, for use when interfacing between the first and second frequencies.
These and other objects, features and advantages will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates in block diagram form an interface circuit known in the art;
FIG. 2 illustrates in graphical form signals associated with the circuit of FIG. 1;
FIG. 3 illustrates in block diagram form data flow of an encode/decode circuit in accordance with the present invention; and
FIG. 4 illustrates in graphical form signals associated with the circuit of FIG. 3.
DETAILED DESCRIPTION OF THE INVENTION
Shown in FIG. 1 is a conventional block diagram of a pulse code modulation (PCM) interface circuit 10. Interface circuit 10 has a data input for serially receiving data, a data clock input for receiving a timing clock, an enable signal, and an algorithm control signal. A data output terminal of interface circuit 10 provides the encoded received data as output data in parallel form.
In operation, interface circuit 10 interfaces between two communication links by receiving eight bits of PCM data in an 8 kHz frame which is a 64 kbps PCM signal and outputting the data in parallel form. Eight successive bits B0 thru B7 of PCM data are serially clocked into the interface circuit 10 in response to the data clock which is an 8 kHz clock signal.
Subsequent circuitry provides an algorithm which controls the amount of signal compression which occurs on the 64 kbps PCM signal. An algorithm control signal is used by interface circuit 10 to correctly format the data for the algorithm used in subsequent circuitry. Typically, the PCM input signal is compressed to a 32 kbps, a 24 kbps, or a 16 kbps ADPCM signal. An individual algorithm is required for each output frequency. In order to properly frame format the data which is clocked into circuit 10, an enable signal is used. Referring to FIG. 2, the enable signal which controls circuit 10 is typically either a "short enable" signal or a "long enable" signal. The short enable signal provides a pulse during the bit immediately preceeding an eight bit frame. Therefore, every time an eight bit frame of data is received by interface circuit 10, a short enable signal pulse is received immediately before the frame boundary. An alternative enable signal format is commonly referred to as a long enable format wherein the long enable signal has a predetermined logic level during the entire frame. In the illustrated form of FIG. 2, the long enable signal defines an eight bit frame. If the algorithm is defined to compress eight bits of PCM data into four bits, the output data is 32 kbps ADPCM. Similarly, if the algorithm is defined to compress eight bits of PCM data into two bits, the output data is 16 kbps ADPCM. However, in order to change algorithms, the algorithm control signal coupled to interface circuit 10 implements the correct data format.
Shown in FIG. 3 is a block diagram of the data flow of an ADPCM transcoder (encode/decode) 12 in accordance with the present invention. Transcoder 12 has an encode portion for receiving PCM data and outputting encoded ADPCM data, and has a decode portion for receiving encoded ADPCM data and outputting decoded PCM data. The encoding and decoding of data may occur simultaneously.
Shown in FIG. 4 is a graphical illustration of signals associated with transcoder 12, and shown in FIG. 5 is a detailed block diagram illustration of the encode portion of transcoder 12 which further illustrates the present invention. In FIG. 5, an encode portion 20 generally comprises a data register 22, a data clock counter 24, a storage queue 26, and an encoder 28. Data register 22 has an input terminal labeled "I" for receiving input data in PCM format and typically at 64 kbps. Data register 22 has a control terminal labeled "C" for receiving an encoded enable signal, and has a clock terminal labeled "Clk" for receiving a data clock. An output terminal of data register 22 labeled "O" is connected to an input terminal of storage queue 26 labeled "I" . Data clock counter 24 has an input terminal labeled "I" for receiving the data clock, and has a control input labeled "C" for receiving the encoded enable signal. An output of data clock counter 24 labeled "O" is connected to an input of encoder 28. An output of encoder 28 is connected to a control data input labeled "C" of storage queue 26. An output of storage queue 26 labeled "O" provides a data output signal.
In operation, assume that the enable signal is an 8 kHz clock signal. The data which is received by data register 22 is a stream of digital data bits having either a logic high or logic low level as indicated by both levels being shown for each bit in FIG. 4. The input data is typically received at the rate of 64 kbps. The encoded enable signal couple to data register 22 and to data clock counter 24 makes data register 22 couple input data at a predetermined rate to queue 26 for storage. Simultaneously, data clock counter 24 counts the clock pulses of the data clock while the encoded enable signal is present in an active state. After the encoded enable signal has changed logic states, clock counter circuit 24 couples a count number to encoder 28. Encoder 28 uses the count number to correlate a predetermined count value to an operational state value. The operational state value is coupled to storage queue 26 along with the input data operand which has a predetermined bit length. The storage queue 26 provides the data operand along with the control information which selects the proper algorithm for further processing by circuitry (not shown) of transcoder 12. The data operand which is stored in queue 26 is subsequently outputted and transmitted as an encoded ADPCM data word after being formatted in accordance with the algorithm.
In the illustrated form, a single enable signal is utilized both for frame synchronization of the data being received by register 22 and for selection of a predetermined algorithm which is used by transcoder 12 to encode data from PCM format to ADPCM format. Data bits received by register 22 may either be logical "one" or "zero" values as indicated in the graph of FIG. 4. As shown in FIG. 4, the enable signal may be implemented in one of many different forms. For purposes of illustration only, four different enable signals are shown in FIG. 4. However, only one of the four illustrated enable signals is needed to implement the present invention. As in the case of the long enable signal of FIG. 2, the enable signal of the present invention functions to establish the beginning and termination of a frame of data. Further, the enable signal may be encoded by one of several ways, such as utilizing the duration or pulse width of the signal, to provide transcoder 12 control information concerning which algorithm to utilize in the interfacing function. Counter 24 provides an encoded count signal of the number of receive data bits counted in response to the width of the enable signal. For example, if the enable signal is present for eight bits as indicated by enable signal 1, the count value of eight may be encoded to indicate that the output of transcoder 12 is to be at 64 kbps and the proper algorithm subsequently selected to implement this frequency. If the enable signal is present for four bits as indicated by enable signal 2, the count value of four may be encoded to indicate that the output of transcoder 12 is to be at 32 kbps ADPCM and the proper algorithm selected to implement this frequency. Similarly, if the enable signal is present for even fewer bits as indicated by enable signals 3 and 4, the count values may be encoded to indicate that the output of transcoder 12 is to be at other ADPCM frequencies and the proper algorithm selected in response thereto to implement those predetermined frequencies. Encoder 28 functions to correlate a received count value with a predetermined state signal which is coupled to storage queue 26. Encoder 28 may be implemented by a conventional circuit to execute the encoding taught herein. Storage queue 26 contains the correct number of bits which were picked out of the stream of bits coupled to register 22 and contains the control information which allows transcoder 12 to modify the data of queue 26 using the proper algorithm.
In the illustrated form, the enable signal is encoded by utilizing the pulse width of the present signal. It should be apparent that other encoding mechanisms may be used such as encoding the enable signal according to signal level. A level detector circuit rather than counter 24 could be used to provide the input signal to encoder 28. Another use of the encoding of the enable signal is to encode the signal with information which places transcoder 12 in special modes of operation such as test modes. For example, if the enable signal remains in a logic high state for longer than the time required to receive eight data bits, the enable signal may be used to force transcoder 12 into a test mode.
Up to this point in the discussion the present invention has been directed toward the receipt of PCM data and the conversion of the data to ADPCM data as occurs in the encode portion of transcoder 12. The operation and use of the present invention applies analogously to the decode portion of transcoder 12 wherein the data received by data register 22 is ADPCM data and the algorithm which is encoded into the enable signal is an algorithm used by transcoder to change the data to PCM data. Therefore, another circuit in the decode portion of transcoder 12 which is similar in all respects to the encode portion 20, except for the format of data received and outputted, is provided in transcoder 12 so that transcoder 12 is able to simultaneously encode and decode data between PCM and ADPCM formats.
By now it should be apparent that a data interface circuit which uses a single control signal for frame synchronization and algorithm selection has been provided. By being able to select a required encoding or decoding algorithm at a correct frame rate with a single control signal, additional circuit inputs have been eliminated which minimizes integrated circuit packaging. Therefore, conventional three-wire PCM interface circuits commonly implemented in PCM coder/decoders (codecs) and filters and in other telephony integrated circuits may be vastly enhanced without adding the requirement for external control signals and packaging inputs. Therefore, the cost to manufacture data interface circuits incorporating the present invention is minimized.
While an embodiment has been disclosed using certain assumed parameters, it should be understood that certain obvious modifications to the circuit or the given parameters will become apparent to those skilled in the art, and the scope of the invention should be limited only by the scope of the claims appended hereto. | A data interface circuit for use when interfacing between two communication links communicating frames of digital data in PCM and ADPCM formats is provided. The data interface circuit provides control information for selecting one of a plurality of algorithms to control the transformation of data between a plurality of PCM and ADPCM formats. A single encoded control signal is utilized to establish frame boundaries and to select a predetermined one of the plurality of algorithms to use in converting between PCM and ADPCM data. | 7 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a lens system for 35 mm lens shutter, and more particularly to a compact and low-cost lens system.
2. Related Background Art
The lens systems for lens shutter cameras are recently decreasing in size while increasing the zoom ratio more and more. The simplest type of lens system, among a variety of zoom types suitable for such lens systems, is a telephoto type lens system composed of two units, a first lens unit G 1 having a positive refractive power and a second lens unit G 2 having a negative refractive power. This zoom type is suitable for compact zoom lenses with some short back focus, and an example of this type is disclosed in Japanese Patent Application Laid-Open No. 3-200912.
Further, an example of a low-cost lens system is disclosed in Japanese Patent Application Laid-Open No. 3-127012, which discloses a lens system employing aspherical surfaces to reduce the number of constituent lenses. In addition, Japanese Patent Application Laid-Open No. 3-200913 discloses a lens system employing a plastic lens.
In the lens system of Japanese Patent Application Laid-Open No. 3-200912, however, the first lens unit G 1 was constructed in an arrangement of positive, negative, and positive refractive powers, in which a component of the negative refractive power had a lens with a strong concave surface facing the object in order to correct a negative spherical aberration and a positive distortion. This lens surface was in turn a convex surface facing the stop, which made corrections of a lower coma difficult, thus causing large aberrations of lower chromatic coma.
In the lens system of Japanese Patent Application Laid-Open No. 3-127012, the first lens unit G 1 was constructed in an arrangement of negative and positive refractive powers and correction of aberrations was effected by using many aspherical surfaces. Off-axis aberrations were substantially improved for monochromatic light in the lens system of the Japanese Patent Application Laid-Open No. 3-127012, but correction of transverse chromatic aberration was not sufficient because the number of constituent lenses was small, thus resulting in insufficient achromatism. Further, lens thickness of each unit (a distance between the most object-side surface and the most image-side surface) was not able to be set small because of low degrees of freedom on correction of aberrations, which was not preferable with respect to the size reduction and weight reduction of the camera. In addition, there was a large gap between a negative lens component and a positive lens component constituting the first lens unit, which caused considerable differences of astigmatism depending upon colors.
Further, in the lens system of Japanese Patent Application Laid-Open No. 3-200913, the first lens unit G 1 was constructed in an arrangement of negative and positive refractive powers, in which a concave lens was made of a low-dispersive glass material and, therefore, a convex component needed to be used for excessive achromatism, which increased the number of lenses in the first lens unit G 1 , thus did not reduce the cost.
SUMMARY OF THE INVENTION
It is, therefore, an object of the present invention to provide a lens system with low cost and thin lens thickness.
The lens system of the present invention has the following structure to achieve the above object.
The lens system has, in order from the object side, a first lens unit G 1 having a positive refractive power, a second lens unit G 2 having a negative refractive power, and a stop located between the first lens unit G 1 and the second lens unit G 2 , wherein a refractive power of the lens system is changed by changing an air gap between the first lens unit G 1 and the second lens unit G 2 ;
wherein the first lens unit G 1 has, in order from the object side, a first lens component L 1 having a negative refractive power, a second lens component L 2 having a negative refractive power, and a third lens component L 3 having a positive refractive power;
wherein the second lens unit G 2 has, in order from the object side, a fourth lens component L 4 having a positive refractive power and a fifth lens component L 5 having a negative refractive power;
wherein either one of the first lens component L 1 and the second lens component L 2 is constructed of a plastic lens and the other is constructed of a glass lens; and
wherein the following conditions are satisfied:
0.29<|φ.sub.p φ.sub.g |·f.sub.a <0.8 φ.sub.p <0, φ.sub.g <0 (1)
0<(rp.sub.1 -rp.sub.2)/(rp.sub.1 +rp.sub.2)<0.15 (2)
0.3<D.sub.a /f.sub.a <0.45 (3)
where
φ p : a refractive power of the plastic lens in the first lens unit G 1 ;
φ g : a refractive power of the glass lens with a negative refractive power;
f a : a focal length of the first lens unit G 1 ;
rp 1 : a paraxial radius of curvature of an object-side lens surface of the plastic lens in the first lens unit G 1 ;
rp 2 : a paraxial radius of curvature of an image-side lens surface of the plastic lens in the first lens unit G 1 ;
D a : a thickness between a most object-side lens surface and a most image-side lens surface in the first lens unit G 1 .
In the above lens arrangement according to the present invention, as compared with the arrangement of positive, negative, and positive refractive powers for the first lens unit G 1 , the position of the principal point of the combination of the first lens component L 1 with the second lens component L 2 is located away from the stop toward the object, because the first lens component L 1 and second lens component L 2 have the negative refractive powers. Accordingly, in addition to having an effect of relieving a positive distortion, the refractive power of each lens component can be made weak, the degrees of freedom of aberration correction can be increased, and the lens thickness of the first lens unit G 1 can be made thinner, because the distance is increased between the principal point position of the combination and the third lens component L 3 .
The thickness reduction of the first lens unit G 1 permits the gap between the second lens component L 2 and the third lens component L 3 to be decreased, thereby suppressing the chromatic differences of coma.
Since the plastic lens is used in the first lens unit G 1 , the costs can be lowered.
Here, it is desired that the first lens component L 1 , second lens component L 2 , fourth lens component L 4 and fifth lens component L 5 each be constructed in a bending configuration that causes as low aberrations for off-axis rays as possible, because they are located away from the stop, and that the third lens component L 3 be constructed in a shape that decreases the amount of negative spherical aberration.
The above conditions of the present invention are described in detail in the following.
The condition (1) is a condition for keeping a balance between the size reduction and the axial aberrations and off-axial aberrations, which defines a suitable position for the principal point position of the combination of the first lens component L 1 with the second lens component L 2 .
First, let us consider the case in which the first lens component L 1 is a plastic lens.
Here, there are the following two cases that violate the upper limit of condition (1):
(a) when the refractive power φ p of the plastic lens becomes strong;
(b) when the refractive power φ g of the glass lens becomes strong.
In the case of (a), because the refractive index of the plastic lens greatly depends on temperature, changes in backfocus and curvature of field become large with a change in temperature, thus being not preferable. In the case of (b), the principal point position of the combination of the first lens component L 1 with the second lens component L 2 becomes closer to the stop, which makes correction of positive distortion difficult.
Conversely, there are the following two cases that fall below the lower limit of condition (1):
(c) when the refractive power φ p of the plastic lens becomes weak;
(d) when the refractive power φ g of the glass lens becomes weak.
In the case of (c), the air gap between the second lens component L 2 and the third lens component L 3 needs to be expanded in order to keep the same principal point position of the first lens unit G 1 , contrary to the desire to reduce the size. In the case of (d), the principal point position of the combination of the first lens component L 1 with the second lens component L 2 becomes further away from the stop, which can maintain well corrected positive distortion, but which makes it difficult to correct the axial chromatic aberration with respect to g-line (435.8 nm) at the wide-angle end.
Next, let us consider the case in which the second lens component L 2 is a plastic lens.
Here, there are the following two cases that fall above the upper limit of condition (1):
(e) when the refractive power φ p of the plastic lens becomes strong;
(f) when the refractive power φ g of the glass lens becomes strong.
In the case of (e), the refractive index of the plastic lens greatly depends on temperature dependence of refractive index, so that changes in focus position and curvature of field become large with a change in temperature, thus being not preferable. In the case of (f), differences of height become small between axial rays and off-axial rays incident into the first lens component L 1 , which makes it difficult to sufficiently suppress changes of coma depending upon field angles at the wide-angle end.
Conversely, there are the following two cases that fall below the lower limit of condition (1):
(g) when the refractive power φ p of the plastic lens becomes weak;
(h) when the refractive power φ g of the glass lens becomes weak.
In the case of (g), it becomes difficult to keep a balance of correction of chromatic aberrations between the axial rays and the off-axial rays. In the case of (h), the correction of axial chromatic aberration with respect to g-line (435.8 nm) at the wide-angle end becomes insufficient, thus being not preferable.
The condition (2) defines a bending shape of the plastic lens in the first lens unit G 1 , which is a condition for keeping the balance between the off-axial aberrations and the axial aberrations.
Above the upper limit of this condition (2), the object-side lens surface of the plastic lens is a concave surface facing the object and differences become small between entrance heights of axial rays and entrance heights of off-axial rays into the plastic lens, which makes it impossible to correct the changes of coma depending upon field angles, thus being not preferable.
Conversely, below the lower limit, the arrangement is effective with respect to the off-axial rays, but cannot suppress the negative spherical aberration, thus being not preferable.
The condition (3) defines an appropriate value of the lens thickness of the first lens unit, in order to reduce the size of the lens system with good performance.
Above the upper limit of condition (3), the lens thickness D a of the first lens unit becomes large, which results in an increase of the size of the lens system, thus being not preferable.
Below the lower limit of condition (3), though the lens thickness D a of the first lens unit is small so as to reduce the size, differences of heights become small between the off-axial rays and the axial rays passing through the respective lens components, which results in failing to suppress the changes of coma depending upon field angles, thus being not preferable.
In the present invention, it is preferable that the following conditions (4) and (5) be further satisfied in addition to the above arrangement.
0.04<D.sub.23 /f.sub.a <0.10 (4)
0.2<|D.sub.b /f.sub.b |<0.4 (5)
where
D 23 : an air gap between the second lens component L 2 and the third lens component L 3 ;
f a : the focal length of the first lens unit G 1 ;
D b : a total thickness of lens system between the most object-side surface and the most image-side surface in the second lens unit G 2 ;
f b : a focal length of the second lens unit G 2 .
Above the upper limit in condition (4), the air gap between the second lens component L 2 and the third lens component L 3 becomes large, which is contrary to the size reduction. Further, the chromatic coma is large, which is not preferable.
Below the lower limit in condition (4), the lens thickness of the first lens unit G 1 is small so as to reduce the size, but the refractive powers of the respective lens components become strong, which makes the correction of coma difficult. Also, the gap tolerance becomes high on production between the second lens component L 2 and the third lens component L 3 , which is against the cost reduction, thus being not preferable.
The condition (5) is for keeping a balance between the size reduction and the correction of off-axial aberrations.
Above the upper limit, the arrangement does not achieve the desired size reduction, thus being not preferable.
Below the lower limit, the arrangement is effective which respect of the size reduction, but the refractive powers of the respective lens components become large, which results in failing to suppress the variations of coma depending upon field angles, thus being not preferable.
Further, it is preferable in the present invention that the following conditions (6) and (7) be satisfied in addition to the above arrangements.
|(ν.sub.1 φ.sub.1 +ν.sub.2 φ.sub.2)/(φ.sub.1 +φ.sub.2)|<35 (6)
|(N.sub.1 φ.sub.1 +N.sub.2 φ.sub.2)/(φ.sub.1 +φ.sub.2)|>1.60 (7)
where
ν 1 : an Abbe's number of the first lens component L 1 ;
φ 1 : a refractive power of the first lens component L 1 ;
ν 2 : an Abbe's number of the second lens component L 2 ;
φ 2 : a refractive power of the second lens component L 2 ;
N 1 : an index of refraction with respect to d-line, of the first lens component L 1 ;
N 2 : an index of refraction with respect to d-line, of the second lens component L 2 .
Above the upper limit in condition (6), the chromatic coma increases, thus being not preferably.
Below the lower limit in condition (7), the Petzval's sum becomes large negatively, which makes correction of positive curvature of field and astigmatism impossible, thus being not preferable.
The above and other objects, features and advantages of the present invention are explained hereinafter and may be better understood by reference to the drawings and the descriptive matter which follows.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a lens layout of Embodiment 1;
FIGS. 2A to 2D are aberration diagrams at the wide-angle end in Embodiment 1;
FIGS. 3A to 3D are aberration diagrams in a state of an intermediate focal length in Embodiment 1;
FIGS. 4A to 4D are aberration diagrams at the telescopic end in Embodiment 1;
FIG. 5 is a lens layout of Embodiment 2;
FIGS. 6A to 6D are aberration diagrams at the wide-angle end in Embodiment 2;
FIGS. 7A to 7D are aberration diagrams in a state of an intermediate focal length in Embodiment 2;
FIGS. 8A to 8D are aberration diagrams at the telescopic end in Embodiment 2;
FIG. 9 is a lens layout of Embodiment 3;
FIG. 10A to 10D are aberration diagrams at the wide-angle end in Embodiment 3;
FIGS. 11A to 11D are aberration diagrams in a state of an intermediate focal length in Embodiment 3;
FIGS. 12A to 12D are aberration diagrams at the telescopic end in Embodiment 3;
FIG. 13 is a lens layout of Embodiment 4;
FIGS. 14A to 14D are aberration diagrams at the wide-angle end in Embodiment 4;
FIGS. 15A to 15D are aberration diagrams in a state of an intermediate focal length in Embodiment 4;
FIGS. 16A to 16D are aberration diagrams at the telescopic end in Embodiment 4;
FIG. 17 is a lens layout of Embodiment 5;
FIGS. 18A to 18D are aberration diagrams at the wide-angle end in Embodiment 5;
FIGS. 19A to 19D are aberration diagrams in a state of an intermediate focal length in Embodiment 5;
FIGS. 20A to 20D are aberration diagrams at the telescopic end in Embodiment 5;
FIG. 21 is a lens layout of Embodiment 6;
FIGS. 22A to 22D are aberration diagrams at the wide-angle end in Embodiment 6;
FIGS. 23A to 23D are aberration diagrams in a state of an intermediate focal length in Embodiment 6; and
FIGS. 24A to 24D are aberration diagrams at the telescopic end in Embodiment 6.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1, FIG. 5, and FIG. 9 are lens layouts of Embodiments 1 to 3, respectively, according to the present invention.
The basic structure of Embodiments 1 to 3 is represented by the lens layout of Embodiment 1 as shown in FIG. 1, in which the lens system has a first lens unit G 1 having a positive refractive power and a second lens unit G 2 having a negative refractive power in order from the object side, and in which, in a refractive power varying (zooming) operation from the wide-angle end to the telescopic end, the first lens unit G 1 and second lens unit G 2 move toward the object so as to decrease the air gap between the two lens units. A stop S is placed between the first lens unit G 1 and second lens unit G 2 . The first lens unit G 1 is composed of a first lens component L 1 that is a negative meniscus lens having a negative refractive power and a convex surface facing the object, a second lens component L 2 having a negative refractive power, and a third lens component L 3 that is a double-convex lens. The second lens unit G 2 is composed of a fourth lens component that is a positive meniscus lens having a positive refractive power and a concave surface facing the object and a fifth lens component L 5 that is a negative meniscus lens having a negative refractive power and a concave surface facing the object, as arranged in order from the object side. The above first lens component L 1 is constructed as a plastic lens.
In Embodiment 1 and Embodiment 3, the second lens component L 2 is a negative meniscus lens having a convex surface facing the object. In Embodiment 2, the second lens component L 2 is a double concave lens having a gentler concave surface facing the object.
FIG. 13, FIG. 17, and FIG. 21 show lens layouts of Embodiments 4 to 6, respectively, according to the present invention.
Since the basic structure of Embodiments 4 to 6 is substantially the same as that of Embodiments 1 to 3 as described above, only differences are described below.
In Embodiments 4 to 6, the second lens component L 2 is made of plastic and is a negative meniscus lens having a convex surface facing the object. In Embodiment 4 and Embodiment 6, the first lens component L 1 is a negative meniscus lens having a convex surface facing the object. In Embodiment 5, the first lens component L 1 is a negative meniscus lens having a gentler concave surface facing the object.
In Embodiments 1 to 6, because the first lens component L 1 , second lens component L 2 , fourth lens component L 4 , and fifth lens component L 5 each are located away from the stop S, each component is formed in a bending shape that causes as small aberrations to the off-axial rays as possible. The third lens component L 3 is formed in a shape to decrease the amount of negative spherical aberration.
Specifications of each embodiment of the present invention are listed below. In the specifications of each embodiment, numerals at the left end represent orders of lens surfaces from the object side, i.e., surface numbers, r represents radii of curvature of the lens surfaces, d represents lens surface separations, n represents indices of refraction, and ν represents Abbe's numbers with respect to d-line (λ=587.6 nm).
In the specifications, surface numbers of aspherical lens surfaces are accompanied by *. Each of the aspherical surfaces can be expressed by the following formula, where a tangent plane is considered at the vertex of the aspherical surface, the origin is taken at a position where the optical axis passes on this tangent plane, a traveling direction of light is positive, and x is a displacement along the optical axis, of the aspherical surface with respect to the vertex of the spherical surface at a position of height y on the tangent plane.
x=cy.sup.2 /{1+(1-κc.sup.2 y.sup.2).sup.1/2 }+c.sub.4 y.sup.4 +c.sub.6 y.sup.6 +c.sub.8 y.sup.8 +c.sub.10 y.sup.10
In the formula, c is a curvature of the aspherical surface (an inverse of radius r of curvature) at the vertex of the aspherical surface, κ a quadratic surface parameter, and C 4 , C 6 , C 8 , C 10 are respective aspherical coefficients.
[Embodiment
______________________________________f = 39.0-50.0--78.0F.sub.NO = 4.1-5.3-8.22ω = 51.2-46.6-31.0°______________________________________r d n ν______________________________________ 1* 14.599 2.45 1.58518 30.2 (plastic) 2* 12.503 1.203 158.198 2.30 1.67270 32.24 20.606 1.705 24.337 3.40 1.51680 64.16 -11.353 2.207 0.000 11.65-7.35-1.89 (stop) 8* -24.650 2.30 1.58518 30.2 (plastic)9 -16.799 4.1010 -10.402 1.50 1.77279 49.511 -31.885______________________________________ 1st surface 2nd surface 8th surface______________________________________κ -0.9568 1.0000 0.0000C.sub.4 -0.1041 × 10.sup.-3 -0.8133 × 10.sup.-4 0.4625 × 10.sup.-4C.sub.6 -0.2961 × 10.sup.-5 -0.3151 × 10.sup.-5 0.1689 × 10.sup.-6C.sub.8 -0.4347 × 10.sup.-7 -0.4498 × 10.sup.-7 0.4595 × 10.sup.-8C.sub.10 0.4559 × 10.sup.-9 0.1079 × 10.sup.-8 -0.1134 × 10.sup.-10______________________________________
Values corresponding to the conditions in the present embodiment are as follows:
|φ.sub.p +φ.sub.g |·f.sub.a =0.661(1)
(rp.sub.1 -rp.sub.2)/(rp.sub.1 +rp.sub.2)=0.074 (2)
D.sub.a /f.sub.a =0.406 (3)
D.sub.23 /f.sub.a =0.063 (4)
|D.sub.b /f.sub.b |=0.282 (5)
|(ν.sub.1 φ.sub.1 +ν.sub.2 φ.sub.2)/(φ.sub.1 +φ.sub.2)|=31.0 (6)
|(N.sub.1 φ.sub.1 +N.sub.2 φ.sub.2)/(φ.sub.1 +φ.sub.2)|=1.662 (7)
[Embodiment
______________________________________f = 39.0-65.0--102.0F.sub.NO = 4.0-6.7-10.52ω = 57.0-36.6-24.0°______________________________________r d n ν______________________________________ 1* 16.802 2.50 1.58518 30.2 (plastic) 2* 14.513 1.203 -114.534 1.80 1.74000 28.24 60.723 1.805 43.568 4.00 1.51680 64.16 -11.897 1.407 0.000 14.6-6.48-2.056 (stop) 8* -28.587 2.50 1.58518 30.2 (plastic)9 -18.823 4.2010 -10.859 1.50 1.77279 49.511 -35.639______________________________________ 1st surface 2nd surface 8th surface______________________________________κ -3.7580 0.4319 -7.4250C.sub.4 0.0000 0.0000 0.0000C.sub.6 -0.3302 × 10.sup.-5 -0.1997 × 10.sup.-5 0.6561 × 10.sup.-6C.sub.8 -0.2866 × 10.sup.-8 -0.1194 × 10.sup.-7 -0.1741 × 10.sup.-8C.sub.10 -0.1307 × 10.sup.-9 0.8592 × 10.sup.-10 0.1857 × 10.sup.-10______________________________________
Values corresponding to the conditions in the present embodiment are as follows:
|φ.sub.p +φ.sub.g |·f.sub.a =0.404(1)
(rp.sub.1 -rp.sub.2)/(rp.sub.1 +rp.sub.2)=0.073 (2)
D.sub.a /f.sub.a =0.396 (3)
D.sub.23 /f.sub.a =0.063 (4)
|D.sub.b /f.sub.b |=0.293 (5)
|(ν.sub.1 φ.sub.1 +ν.sub.2 φ.sub.2)/(φ.sub.1 +φ.sub.2)|=28.5 (6)
|(N.sub.1 φ.sub.1 +N.sub.2 φ.sub.2)/(φ.sub.1 +φ.sub.2)|=1.717 (7)
[Embodiment
______________________________________f = 39.0-50.0--78.0F.sub.NO = 4.1-5.3-8.22ω = 51.2-46.6-31.0°______________________________________r d n ν______________________________________ 1* 13.026 2.17 1.58518 30.2 (plastic) 2* 10.335 1.203 74.845 1.77 1.68893 31.14 20.100 1.655 23.407 2.87 1.51680 64.16 -10.200 1.767 0.000 10.39-4.80-1.87 (stop) 8* -22.201 2.02 1.58518 30.2 (plastic)9 -16.557 4.6510 -9.783 1.31 1.77279 49.511 -29.750______________________________________ 1st surface 2nd surface 8th surface______________________________________κ -3.7580 0.4319 -7.4250C.sub.4 -0.9583 1.0000 0.0000C.sub.4 -0.2181 × 10.sup.-3 -0.2286 × 10.sup.-3 0.5175 × 10.sup.-4C.sub.6 -0.7734 × 10.sup.-5 -0.8288 × 10.sup.-5 0.3974 × 10.sup.-6C.sub.8 0.3222 × 10.sup.-7 0.9204 × 10.sup.-7 0.3259 × 10.sup.-8C.sub.10 -0.1341 × 10.sup.-9 0.3038 × 10.sup.-9 -0.3015 × 10.sup.-11______________________________________
Values corresponding to the conditions in the present embodiment are as follows:
|φ.sub.p +φ.sub.g |·f.sub.a =0.393(1)
(rp.sub.1 -rp.sub.2)/(rp.sub.1 +rp.sub.2)=0.115 (2)
D.sub.a /f.sub.a =0.403 (3)
D.sub.23 /f.sub.a =0.069 (4)
|D.sub.b /f.sub.b |=0.326 (5)
|(ν.sub.1 φ.sub.1 +ν.sub.2 φ.sub.2)/(φ.sub.1 +φ.sub.2)|=30.9 (6)
|(N.sub.1 φ.sub.1 +N.sub.2 φ.sub.2)/(φ.sub.1 +φ.sub.2)|=1.662 (7)
[Embodiment
______________________________________f = 39.0-50.0--78.0F.sub.NO = 4.1-5.3-8.22ω = 57.8-46.2-31.0°______________________________________r d n ν______________________________________1 400.000 1.50 1.67270 32.22 31.549 0.30 3* 19.640 3.30 1.58518 30.2 (plastic) 4* 17.037 2.305 59.105 3.40 1.51860 70.06 -10.847 2.207 0.000 11.77-7.48-2.01 (stop) 8* -39.761 2.30 1.58518 30.2 (plastic)9 -20.501 4.2510 -11.178 1.50 1.71700 48.011 -62.820______________________________________ 3rd surface 4th surface 8th surface______________________________________κ 0.4034 0.2157 0.2991C.sub.4 -0.3019 × 10.sup.-3 -0.1532 × 10.sup.-3 0.3928 × 10.sup.-4C.sub.6 -0.4545 × 10.sup.-5 -0.3449 × 10.sup.-5 0.3371 × 10.sup.-6C.sub.8 -0.4977 × 10.sup.-9 -0.4114 × 10.sup.-7 -0.2399 × 10.sup.-8C.sub.10 -0.1860 × 10.sup.-9 0.3417 × 10.sup.-10 0.2805 × 10.sup.-10______________________________________
Values corresponding to the conditions in the present embodiment are as follows:
|φ.sub.p +φ.sub.g |·f.sub.a =0.467(1)
(rp.sub.1 -rp.sub.2)/(rp.sub.1 +rp.sub.2)=0.071 (2)
D.sub.a /f.sub.a =0.397 (3)
D.sub.23 /f.sub.a =0.085 (4)
|D.sub.b /f.sub.b |=0.288 (5)
|(ν.sub.1 φ.sub.1 +ν.sub.2 φ.sub.2)/(φ.sub.1 +φ.sub.2)|=31.9 (6)
|(N.sub.1 φ.sub.1 +N.sub.2 φ.sub.2)/(φ.sub.1 +φ.sub.2)|=1.663 (7)
[Embodiment
______________________________________f = 39.0-50.0--78.0F.sub.NO = 4.1-5.3-8.22ω = 56.8-46.2-31.0°______________________________________r d n ν______________________________________1 -330.236 1.50 1.61750 30.82 44.061 0.30 3* 20.849 3.20 1.58518 30.2 (plastic) 4* 17.251 2.355 71.943 3.20 1.5186 70.06 -10.925 2.207 0.000 11.6-7.34-1.88 (stop) 8* -38.225 2.30 1.58518 30.2 (plastic)9 -20.408 4.2510 -11.063 1.50 1.71700 48.011 -56.855______________________________________ 1st surface 2nd surface 8th surface______________________________________κ 0.3691 0.2144 0.2991C.sub.4 -0.3043 × 10.sup.-3 -0.1649 × 10.sup.-3 0.4087 × 10.sup.-4C.sub.6 -0.4079 × 10.sup.-5 -0.3011 × 10.sup.-5 0.4031 × 10.sup.-6C.sub.8 -0.9347 × 10.sup.-8 0.2809 × 10.sup.-7 -0.3068 × 10.sup.-8C.sub.10 -0.1064 × 10.sup.-10 0.1755 × 10.sup.-9 0.3344 × 10.sup.-10______________________________________
Values corresponding to the conditions in the present embodiment are as follows:
|φ.sub.p +φ.sub.g |·f.sub.a =0.325(1)
(rp.sub.1 -rp.sub.2)/(rp.sub.1 +rp.sub.2)=0.094 (2)
D.sub.a /f.sub.a =0.388 (3)
D.sub.23 /f.sub.a =0.086 (4)
|D.sub.b /f.sub.b |=0.288 (5)
|(ν.sub.1 φ.sub.1 +ν.sub.2 φ.sub.2)/(φ.sub.1 +φ.sub.2)|=30.7 (6)
|(N.sub.1 φ.sub.1 +N.sub.2 φ.sub.2)/(φ.sub.1 +φ.sub.2)|=1.611 (7)
[Embodiment
______________________________________f = 39.0-50.0--78.0F.sub.NO = 4.1-5.3-8.22ω = 56.8-46.2-31.0°______________________________________r d n ν______________________________________1 1301.444 1.50 1.67270 32.22 41.200 0.30 3* 20.740 3.10 1.58518 30.2 (plastic) 4* 16.753 2.505 56.506 3.40 1.51860 70.06 -11.147 2.207 0.000 11.27-7.11-1.82 (stop) 8* -35.824 3.00 1.58518 30.2 (plastic)9 -21.250 4.5010 -10.894 1.50 1.71700 48.011 -46.601______________________________________ 3rd surface 4th surface 8th surface______________________________________κ 0.4034 0.2157 0.2991C.sub.4 -0.2903 × 10.sup.-3 -0.1521 × 10.sup.-3 0.4787 × 10.sup.-4C.sub.6 -0.4319 × 10.sup.-5 -0.3218 × 10.sup.-5 0.1128 × 10.sup.-6C.sub.8 0.1737 × 10.sup.-7 0.4413 × 10.sup.-7 0.4851 × 10.sup.-8C.sub.10 -0.3966 × 10.sup.-9 -0.904 × 10.sup.-10 -0.2668 × 10.sup.-10______________________________________
Values corresponding to the conditions in the present embodiment are as follows:
|φ.sub.p +φ.sub.g |·f.sub.a =0.296(1)
(rp.sub.1 -rp.sub.2)/(rp.sub.1 +rp.sub.2)=0.107 (2)
D.sub.a /f.sub.a =0.401 (3)
D.sub.23 /f.sub.a =0.093 (4)
|D.sub.b /f.sub.b |=0.328 (5)
|(ν.sub.1 φ.sub.1 +ν.sub.2 φ.sub.2)/(φ.sub.1 +φ.sub.2)|=31.7 (6)
|(N.sub.1 φ.sub.1 +N.sub.2 φ.sub.2)/(φ.sub.1 +φ.sub.2)|=1.698 (7)
FIGS. 2A to 4D are aberration diagrams of Embodiment 1 of the present invention, FIGS. 6A to 8D are aberration diagrams of Embodiment 2 of the present invention, FIGS. 10A to 12D are aberration diagrams of Embodiment 3 of the present invention, FIGS. 14A to 16D are aberration diagrams of Embodiment 4 of the present invention, FIGS. 18A to 20D are aberration diagrams of Embodiment 5 of the present invention, and FIGS. 22A to 24D are aberration diagrams of Embodiment 6 of the present invention.
Here, FIGS. 2A to 2D, 6A to 6D, 10A to 10D, 14A to 14D, 18A to 18D, and 22A to 23D are aberration diagrams in a state of the shortest focal length at the wide-angle end; FIGS. 3A to 3D, 7A to 7D, 11A to 11D, 15A to 15D, 19A to 19D, and 23A to 23D are aberration diagrams in a state of an intermediate focal length; FIGS. 4A to 4D, 8A to 8D, 12A to 12D, 16A to 16D, 20A to 20D, and 24A to 24D are aberration diagrams in a state of the longest focal length at the telescopic end.
In each aberration diagram of astigmatism, the broken lines represent the meridional image surface and the solid lines represents the sagittal image surface.
It is seen from comparison between the aberration diagrams that the lens systems according to the present invention have excellent imaging performance from the wide-angle end to the telephoto end even though they are compact, relatively small in number of constituent lenses, and thin in lens thickness.
As described above, the present invention can realize lens systems for compact cameras, which are compact, relatively small in number of constituent lenses, and low in cost. Also, the present invention can employ any focusing method including the entire system feed-out, first unit feed-out, second unit feed-out, and floating methods. In addition, the anti-vibration effect can be achieved by decentering all of either the first lens unit or the second lens unit with respect to the optical axis or decentering a part of either the first lens unit or the second lens unit with respect to the optical axis. | A lens system has a front unit having a positive refractive power and a rear unit having a negative refractive power, in order from the object side, and performs a refractive power varying (zooming) operation by changing an air gap between the two units. The front unit is composed of three lens components of negative, negative, and positive refractive powers. | 6 |
FIELD
This invention relates to production of textile yarns.
PRIOR ART
It is known that core/wrap or wrapped core yarns may be produced by wrapping a fibrous sheath around a continuous-filament core. Alternatively, a continuous filament may be wrapped around a staple fiber core. Still further both the core and wrapping or sheathing may consist of staple fibrous materials, or both may be filament materials. To date, in the production of core/wrap yarn with fibrous materials the wrapping step has been carried out prior to ring spinning, i.e. during the formation of roving from sliver, thereby producing a core/wrap roving which subsequently must be spun into yarn in a ring spinning step; or during the drawing process, thereby producing a concentrically cored sliver, which subsequently must be roved into roving and spun into yarn in a ring spinning step. To date no practical system has been developed to directly produce core/wrap yarn in a ring-spinning frame from a plurality of unwrapped roving strands.
The following definitions apply to several terms that appear in the specification and claims:
Carding-the use of a carding machine to align, clean and straighten fibers, and to remove very short fibers as well as fine trash to produce sliver.
Drawing-the making parallel and straightening of sliver fibers to improve the uniformity of linear density, usually accomplished in 1, 2, or 3 passages through drawing equipment known as a draw frame or drafting frame. In each passage through a draw frame several sliver strands are combined into a single sliver strand.
Drafting - the process whereby a fiber bundle such as a sliver or roving is extended in length in order to reduce the linear density of the bundle and to increase the parallelization of the fibers. Various forms of drafting are employed in carding, drawing, roving, and ring-spinning.
Sliver-the product produced by carding or drawing, i.e. a very coarse strand of fibers having essentially no twist.
Roving process-conversion of sliver by drafting into a thinner strand called a roving in which a small amount of twist (normally one to two turns per inch) is imparted to the strand. This step is performed only in conjunction with subsequent ring spinning. No other type of spinning presently requires roving prior to spinning.
Ring-spinning process-As used herein, an operation for converting roving into yarn by drafting a roving and imparting twist through use of a ring and a moving traveler on a ring-spinning frame. A small percentage of ring-spinning machines do not require prior formation of roving but instead convert sliver directly into yarn except that the sliver is passed through additional drafting apparatus on the ring frame immediately prior to passage through the ordinary draft rolls/aprons associated with ring spinning.
SUMMARY
A new system is provided for directly producing core/wrap yarn from a plurality of unwrapped rovings. Broadly, the invention comprises feeding a core strand and at least one wrap strand on each side of the core strand from the nip of a pair of front draft rollers of a ring-spinning assembly directly to a gripper nip immediately downstream from and closely adjacent to the nip of the front draft rollers. The core strand travels directly to the gripper nip. The wrap strands which are spaced from the core strand at the front roller nip, converge with the core strand at the gripper nip and wrap around the core strand immediately before the nip so as to form core/wrap yarn in the gripper nip.
The wrapped yarn then is passed through an ordinary ring traveler to the wind-up spindle of the ring-spinning assembly. In this manner, unwrapped roving is converted to core/wrap yarn in a continuous process on the ring-spinning frame.
It is an object of the present invention to produce a new core/wrap yarn having the following advantages and distinctions over previous yarn products:
It is covered at least 90% compared to much lesser percentage of previous core/wrap products.
The core fibers are oriented along the length of the yarn and are positioned in the middle of the cross-section.
Due to unique interlacing of the cover fibers (effected by two strands of drafted rovings, one on each side of the core material), the yarn sheath does not strip from the core at all. Furthermore, the strip resistance is equally good in both directions along the yarn.
The staple-core/cotton-wrap yarn produced with a high tenacity staple fiber is significantly stronger than an equivalent 100% cotton yarn or an equivalent, regular intimate-blend yarn.
The device is capable of producing relatively fine yarns (e.g. yarns of up to 40/1 cotton count or finer).
Both the core as well as cover fibers contribute to the mechanical properties of the yarn produced by the present system; and mechanical properties such as tear strength, tensile strength and abrasion resistance of the fabrics produced from such yarns have exhibited significant improvements.
The staple-core-spun yarns of the present invention are economical compared to existing filament-core yarns mainly because of the lower cost of the staple fibers, compared to filament yarns.
Inferior quality cotton wool manmade fiber or any other fiber can be used in the core, and the premium fiber can be utilized in the cover to produce a premium-looking product.
Many types of novelty yarns and fabrics such as crepe-like denim-like, and differential dye effects can be producing by the spinning technique of the present invention.
It is much easier to piece-up the ends during spinning, when compared to earlier reported spinning techniques.
The staple-core yarns are highly useful for producing textile products where high strength and cotton surface are both desirable and/or critical, such as strong, easy-to-care-for and comfortable apparel of predominantly cotton; certain military fabrics, such as tentage, chambray shirting work uniforms, strong sewing threads with heat-insulation cotton cover and strong pill-resistant fabrics.
Other objects and advantages of the present invention will be obvious from the following detailed description in conjunction with the drawings in which:
FIG. 1 is a perspective view of the overall system of the present invention.
FIG. 1a is a preferred embodiment.
FIG. 1b is an alternative embodiment.
FIG. 2 is an oblique top-front view of the yarn wrapping and formation zone of the present invention.
FIGS. 2a and 2b illustrate alternative wrapping designs.
DETAILED DESCRIPTION
Components of ordinary ring spinning equipment may be employed in the practice of the present invention. These are illustrated in FIG. 1 as rear draft rollers 1, drafting aprons 2 front draft rollers 3, pigtail guide 4, ring 5 and yarn spindle 6. Hereinafter, this combination of elements is referred to as a single spinning system.
In addition, there are at least three bobbins upstream of rear draft rollers 1. Two of these bobbins feed wrap roving 9 and 10 such as cotton roving to rear rollers 1, while the other bobbin feeds core roving 12 such as polyester roving thereto.
Starting materials for the practice of the present invention such as cotton or polyester rovings may be prepared in a conventional manner.
A conventional roving condenser 14 is disposed between the bobbins and rear rollers 1 in order to maintain a space between rovings.
As to the degree of spacing between each wrap and core at the front roller nip, this will depend upon the fiber length being processed, and consequently on the size of the spinning equipment (i.e. short-, mid-, or long-staple spinning equipment). For a conventional cotton (short-staple) spinning system, the space between wrap and core strands may be about 3/32" to 5/32". For long staple fibers such as wool, this dimension may vary from about 1/4" to 5/8".
Referring again to FIG. 1, disposed between pigtail guide 4 and front rollers 3 is a pair of opposed, rotatable, spring-loaded rollers 20 which define opposing, curved, convex surfaces that provide a gripper nip. The plane of the gripper nip is perpendicular to the plane of the front roller nip. The rollers may be secured to a bracket 25 which in turn may be secured to the frame of the ring-spinning assembly.
A preferred design is illustrated in FIG. 1a. Therein the gripper nip zone is provided by opposing leaf springs.
In the alternative embodiment of FIG. 1b, the wrapped yarn-forming or gripper zone is provided by two rollers 35 and 37. Roller 35 is fixed. Roller 37 may be moved around its slightly off-center axis 38 by means of adjusting the position of weight 40 on screw 41 that is fixed to roller 37. Since the axis of rotation of roller 37 is slightly off-center, then any rotational movement thereof alters the distance between rollers 35 and 37, thereby altering the gripping pressure therebetween.
Whatever the gripper design, the gripper nip is aligned with the point of emergence of the core strand from the front roller nip so that the core strand travels in a path perpendicular to the front roller nip directly into the gripper nip. At the same time the wrap strands travel at an angle to the front roller nip and are guided into the gripper nip by the opposing outwardly flared surfaces of the opposed convex surfaces at the entrance of the gripper nip, as can be seen in the top view of FIG. 2.
Within the gripper, the wrap strands wrap around the core strand either in the manner of FIG. 2a or 2b.
The surfaces of the gripper body which directly contact the fibrous strands most preferably are polished.
The distance from the front draft roller nip to the gripper nip should be such that there is essentially no drafting of the core strand between these two points. Thus, the distance between yarn wrapping zone and the front roller nip, measured along the core strand, is less than the length of most of the fibers in the core strand. By avoiding drafting in the core the full yarn tension is maintained in the core strand upstream of the gripper. The loss of this tension otherwise would allow excessive "twist" upstream of the gripper assembly and would result in barber-poling and less than subsequent full coverage of the core strand by the wrap strands.
With regard to fiber length in the wrap strands, the distance from the front draft-roller nip to the gripper nip should be such that there is no drafting of the longest fibers in the wrap strands (e.g., for cotton, shorter than the so-called "2.5% span length" or "staple" length) but that there is drafting of some of the shorter fibers therein. In other words the distance along each wrap strand from the point of emergence of each wrap strand at the front roller nip to the yarn formation point at the gripper nip is greater than the shortest fiber length therein but less than the staple length (e.g., about 50-80% of the staple length for cotton or wool wrapper). In the case of cotton wrapper fibers, the distance along the wrap strands measured from front roller nip to yarn formation typically is about 1/2" to 7/8".
Thus, in the practice of the present invention, the fibers, after emerging from the nip of the front rollers, are loose with no twist to hold them together except for the slight twist imparted to the core-strand-fibers during their passage from front draft roller nip to gripper nip by twist flowing back upstream of the gripper.
In addition to its distance from the front roller nip, the gripper nip generally is positioned so that the axes of the gripper rolls are normal to the plane which is tangent to both front drafting rollers and contains the line of contact between the front rollers.
The gripping force within the gripper nip is adjusted so that twist is imparted to the core strand prior to wrapping. A force within 6 grams to 12 grams generally will be suitable for many strands. The exact magnitude of the gripping force, which varies from yarn to yarn, is a function of yarn count and spinning tension. The gripping force (normal to the yarn axis) produces a frictional drag on the yarn at the gripping point. This drag is essentially the spinning tension, i.e., the tension of the yarn between the gripper and ring/traveler. Excessive gripping force should be avoided because it will cause an "end down" (break) when the spinning tension exceeds the strength of the core component of the yarn. Insufficient gripping force should be avoided because it will allow too much of the twist to flow back up into the fiber assemble zone between the gripper nip and the front roller nip, which leads to the undesirable barber-pole effect. Generally the twist should flow back about 20% to 40% of the distance along the core strand from gripper nip to front roller nip.
The following are exemplary gripping forces for specific materials and wind-up spindle speeds:
______________________________________Wrap Core YarnMaterial Material Count Spindle Speed Grip Force______________________________________1. Cotton Polyester 20/1 10,000 rpm 10 grams2. Cotton Polyester 40/1 10,000 rpm 6 grams3. Cotton Cotton 20/1 8,000 rpm 8 grams______________________________________
The radius of curvature of surfaces at the gripper nip generally will range from about 1/2" to 1" depending upon yarn counts and types. For a 20/1 yarn composed of cotton-wrap/polyester-core, a radius of curvature of 1/2" is suitable.
With regard to the operational speeds of the system of the present invention, spindle speed may be the same as that employed to spin yarn of a given linear density and twist multiple, in the ordinary manner, from a roving having the same overall blend composition and combined linear density as the three rovings (two wrapper plus core). In this case approximately the same twist gear and the same draft gear ratio would be used and the same linear density yarn produced. The three rovings creeled per position in the present invention, however, would each have to be prepared with linear densities, on the average, one-third of the linear density of the conventional roving.
Alternately, a separate approach would be to use three rovings each having the same linear density as the comparable conventional single roving. In this case, however, the draft gear would be selected to increase the draft by a factor of three because three times as much roving (three rovings versus one roving) is pieced into the drafting zone. The same twist gear and spindle speed would produce the same yarn linear density and twist multiple as in the conventional single-roving case.
A third and more practical approach would combine a change in linear density of the rovings with a change in draft gearing. One possible combination would be to reduce the roving linear densities by a factor of two, and increase the draft by a factor of 1.5. For instance, if a 1-hank roving is normally used with a draft of 28 to produce Ne 28 yarn in the conventional way, then three 2-hank rovings (one core and two wrapper rovings of different composition) could be used with a draft of 42 to produce Ne 28 core/wrap yarn from the present invention. Once again the spindle speed and twist gear ratio of the machine would be the same, as would the resultant twist multiple of the yarn produced.
Many other practical combinations exist. In cotton ring spinning, it is generally desirable to keep the draft below 50, and the roving linear density heavier than three hank. The exact combination would be chosen by the experienced textile technologist based on the available equipment and the overall processing requirements. Variations in the twist multiple, production rate, and yarn count are accomplished by purely conventional manipulation of the textile relationships between the variables of roving linear density, ring size, spindle speed, twist and draft gearing, traveler weight, and so forth. The following are general spinning parameters for a 28-tex, 67% cotton/33% polyester-staple-core yarn produced by the system of the present invention:
polyester roving (1)=2-hank (1.5"; 1.2 denier; and 6 g/denier)
cotton rovings (2)=2-hank (1-1/16" staple; Acala):
combined hank of rovings=0.67
total draft=42
spindle speed (rpm)=9,100
twist multiple=4.00
traveller=#6 (1.6 grains)
relative humidity=51
temperature (C)=20
The present invention may be employed to wrap fibrous materials around continuous filament core materials such as continuous filament polyester, as well as around staple core material. When such continuous filament materials is employed as the core strand instead of being introduced into the drafting system through the back rolls the filament core is fed into the drafting system immediately behind the front rollers in between the wrapper strands. The operational speeds of the drafting zone and spindle speed are the same as for a similar system employing staple core material of the same linear density. The resulting product made from continuous polyester filament core strand and cotton wrap quite surprisingly has the same excellent strip resistance as a core/wrap yarn having a staple-core strand.
In still another operational arrangement, the gripper means or wrapped yarn-formation nip, may be rotated 90 degrees so that the gripper nip is not perpendicular to the front roller nip, but rather is parallel to the front roller nip and lies in the plane tangent both to the front rollers and to the gripper surfaces. In this system, the outwardly flared opposing surfaces of the opposed, convex surfaces at the entrance to the gripper nip no longer provide means to guide the wrap strands to the nip. When two wrap strands are present in such an embodiment, the spacing between the core strand and one of the wrap strands at the front roller nip preferably is different than the spacing between the core strand and the other wrap strand. In particular the spacing between rovings 9 and 12 of FIG. 1 would be slightly less than the spacing between rovings 10 and 12 in the case of a "Z" twist at yarn formation (FIG. 2a), and vice-versa in the case of "S" twist (FIG. 2b). Generally, the lesser spacing is about 70-80% of the greater spacing between centerlines of respective strands. This unequal spacing may be accomplished by a condenser disposed upstream of the front roller nip, that has unequal spacing between its condenser holes. | A core/wrap yarn is formed on a conventional ring-spinning yarn system by including a gripper nip immediately downstream from and closely adjacent to the front roller nip of the system; feeding a core strand and at least one wrap stand on each side of the core strand from the front roller nip to the gripper nip, wherein the wrap strands are spaced from the core strand at the front roller nip and converge with the core strand in the gripper nip to wrap around the core strand in the gripper nip so as to form wrapped yarn which then is passed through a ring traveler on to the wind-up system. | 3 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a blow bar for an impact crusher, in particular a rotary impact crusher, having a carrier, which, in a region of a cutting edge, has a plurality of cutting elements made of hard material arranged next to one another.
2. Discussion of Related Art
European Patent Reference EP 0 581 758 B1 discloses a rotary impact crusher equipped with several blow bars. The blow bar includes a carrier that can be clamped by a wedge clamp to an anchoring attachment to permit the blow bar to be interchangeably affixed to the rotor of a rotary impact crusher. The carrier has a seating surface facing in the tool-advancing direction onto which a plurality of cutting elements are placed and can be lined up in a longitudinal direction of the blow bar. The cutting elements are first placed loosely onto the carrier. As soon as the wedge connection is clamped, then the cutting elements are affixed to the carrier in captive fashion. If one or more of the cutting elements becomes worn, then the clamped connection must be released. Then the respective cutting elements can be replaced with non-worn cutting elements. This known type of fixing the cutting elements to the carrier has turned out to be unsuitable in actual practice. In particular, when the blow bar to be serviced is in a lower position of the rotor, after the clamped connection is released, the cutting elements can fall in an uncontrolled fashion and must then be laboriously collected and placed onto the carrier. Furthermore, the contact surfaces of the carrier and cutting elements must be very precisely matched to one another in order to enable a gap-free connection. Because the cutting elements, which are embodied as sintered components, can only be produced within a certain tolerance range, the gap-free association with the carrier can never be completely guaranteed, leading to frequent breakage of cutting elements.
German Patent Reference DE 23 43 691 discloses another blow bar having three hard metal plates fastened to a carrier. Here, a screw connection is used to clamp the hard metal plates into recesses in the carrier. German Patent Reference DE 295 21 050 U1 discloses a similar arrangement in which the carrier of the blow bar has a dovetail-shaped groove into which a dovetail-shaped insertion lug of the bar-shaped cutting element is slid. In blow bars of this type, there is frequently the danger that powerful impact stress results in bar breakage. Then, the entire cutting element must be expensively replaced.
German Patent Reference DE 16 58 400 U1 discloses another blow bar in which a hard metal block extending the entire width of the blow bar is soldered to the carrier.
SUMMARY OF THE INVENTION
One object of this invention is to provide a rugged blow bar that is easy to service.
This object of this invention is attained with two or more cutting elements fastened on a cutting element holder so that it is possible to interchangeably fasten two or more cutting element holders to the carrier.
Two or more cutting element holders are thus built into the unit to produce the cutting edge and in turn carry two or more cutting elements. The cutting element holders thus form or constitute individually manipulable subassemblies that can be securely installed on the carrier in a short amount of time in order to produce the cutting edge. If abrasion has caused the cutting element to reach its wear limit, then the cutting element holder that carries this cutting element can be removed and replaced independently of the other cutting element holders. This permits the maintenance to be carried out in a time-optimized, economical, and reliable fashion.
In one embodiment of this invention, the cutting elements are integrally joined to the cutting element holder, preferably soldered. This achieves a gap-free, non-breakage-prone association or connection between the cutting elements and the cutting element holder.
In one embodiment of this invention, the carrier has a recess with a supporting surface and a bearing surface at an angle thereto, with the supporting surface facing in the tool-advancing direction, the cutting element holder is supported on this supporting surface by a contact surface facing away from the tool-advancing direction, and a bottom adjoining the contact surface of the cutting element holder rests against the supporting surface over a large area. This invention recognizes that during the tool engagement, there is a varying course of the force. The supporting surface and the bearing surface reliably intercept these machining forces and divert them into the carrier, so that the cutting element holder is always securely fixed.
In another embodiment of this invention, the cutting element holder is connected to the carrier by at least one fastening lug, which is inserted into a fastening socket and the fastening lug has a threaded opening that is flush with a screw opening that feeds into the fastening socket. The fastening lug can be disposed on the cutting element holder and the fastening socket can be disposed on the carrier, or vice versa. When transverse forces occur, the fastening lug is supported in the fastening socket and carries the forces past or beyond this supporting region. Thus the fastening screws, which connect the cutting element holder to the carrier, are kept fee of transverse forces. With this simple provision, a markedly improved diversion of force is possible.
If it is possible to position the cutting element holders in a preassembly position on the carrier in which they are adjustable relative to one another, then the cutting element holders in the preassembly position can be pushed against one another without play and then finally fixed in position. As a result, the cutting elements can be pushed against one another without play, and thus in the connection points during tool use, no harmful transverse forces can become operative.
In this embodiment, for example, a blow bar of this invention provides the fastening lug inserted with play into the fastening socket, and when the connection, preferably a threaded connection, is released, the cutting element holder is adjustable to a limited degree in the longitudinal direction of the cutting edges.
If the carrier has screw openings that are let into the carrier from the rear facing away from the tool-advancing direction and fastening screws are inserted through the screw openings and screwed into the cutting element holder, then the screw head is positioned on the back side of the carrier in a wear-protected fashion. Then, if needed, the fastening screw can always be reliably loosened. If the fastening screw is screwed into a threaded opening in the form of a blind hole in the cutting element holder, then the threaded opening is accommodated in a protected fashion as well, and no crushed material that would block the threaded connection can penetrate into the threaded region.
To minimize carrier wear, one embodiment of this invention provides that at the radially outer end facing away from the tool-advancing direction, the cutting element holder has a chip-diverting surface that transitions in a flush manner into a diverting surface of the carrier. Thus, the carrier is covered by the cutting element holder and is protected against the rock material to be crushed.
A blow bar according to this invention can be arranged to that transversely to the tool-advancing direction, the cutting element holder is adjoined by a front surface of a base part of the carrier and that an impact rocker is attached to the base part, facing away from the cutting insert. By equipping the blow bar with cutting elements according to this invention, wear in the vicinity of the cutting edge is initially optimized. As a result, reduced wear to the impact rocker then surprisingly ensues.
One object of this invention is also attained with a cutting insert for a blow bar, having a cutting element holder to which a plurality of cutting elements made of hard material are attached, in which the cutting elements are arranged next to one another transversely to the tool-advancing direction and form a cutting edge. In this embodiment, the cutting element holder has a rear contact surface facing away from the tool-advancing direction, from which a fastening lug integrally formed onto the cutting element holder protrudes. This fastening lug is preferably provided with a threaded opening. This cutting insert can be built easily and quickly onto a carrier of a blow bar. Thus, the cutting insert need merely be inserted by its integrally formed-on fastening lugs in fastening sockets, provided for them, in the carrier. The cutting insert can then be screwed to the carrier via the threaded openings in the fastening lug. The fastening lugs keep the fastening screws free from transverse forces exerted during tool use. Thus stable coupling of the cutting insert to the carrier is realized. In the event of damage, the cutting insert can easily be replaced by undoing the threaded connections and then removing the cutting element holder from the carrier. It can then be replaced with a new, unworn cutting insert.
The fastening lug can be manufactured simply and dimensionally precisely if it has a square or rectangular geometry in cross-section.
Preferably, the central longitudinal axis of the threaded opening extends vertically relative to the contact surface so that the forces induced by the fastening screw are transferred directly into the contact surface. It has been demonstrated that a very stable coupling of the cutting insert, without the risk of breakage, is possible as a result.
One embodiment of a cutting insert includes the cutting element holder having a bottom that adjoins the contact surface at right angles to it. By the bottom and the contact surface, the cutting insert can be optimally supported on corresponding bearing surfaces.
If the cutting element holder has a seating surface, which is inclined away from the tool-advancing direction and to which the cutting elements are coupled over a large area by a supporting section, then a geometry of the cutting element holder that is easy to manufacture is possible, and the inclined seating surface optimally takes into account the varying course of the force during tool engagement and thus serves to brace the cutting element reliably. The cutting element can in particular be soldered to the seating surface, to ensure a play-free connection.
Another wear protection of the cutting insert can be produced so that the cutting element holder has a receiving region in which a plurality of wear plates made of hard material are lined up in the longitudinal direction of the cutting insert and the wear plates, adjoin the cutting elements directly. Because a plurality of wear plates are used, a segmented structure is produced, which results in a significantly reduced risk of breakage for the wear plates. The lining up of the wear plates, which should in particular be free of gaps, prevents the wear plates from being subjected to undue transverse forces, which could break them. Because the wear plates directly adjoin the cutting elements, this prevents the wear plates from eroding the region under the cutting elements.
In this case, it can be advantageous for two wear plates per cutting element to be installed and for the cutting elements to have double the width of the wear plates in the longitudinal direction of the cutting insert.
A cutting insert according to this invention can have the cutting elements triangular in cross-section and can have an impact surface facing in the tool-advancing direction and at an angle thereto have a free surface facing away from the tool-advancing direction. The free surface and the advancing normal oriented in the tool-advancing direction enclose a free angle so that the free surface slopes downward from the cutting edge in the direction opposite the tool-advancing direction. This design produces a self-sharpening geometry for the cutting element. As a result, when an abrasion-induced wear of the cutting elements occurs, a sharp-edged cutting is retained.
BRIEF DESCRIPTION OF THE DRAWINGS
This invention is explained in greater detail in view of an exemplary embodiment shown in the drawings, wherein:
FIG. 1 shows a blow bar in perspective in a side view;
FIG. 2 shows the blow bar of FIG. 1 in perspective in a rear view;
FIG. 3 shows a cutter insert, which can be built into the blow bar of FIGS. 1 and 2 , in a fragmentary perspective view;
FIG. 4 shows the cutting insert of FIG. 3 in a side view;
FIG. 5 shows the cutting insert of FIG. 4 in a front view; and
FIG. 6 shows the cutting insert of FIGS. 3-5 in perspective in a rear view.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 shows a blow bar, which has a carrier 10 . The carrier 10 has a base part 11 , which forms a front face 12 pointing in the tool-advancing direction (V). The base part 11 is adjoined laterally by a lower part 13 , and the impact rocker 13 has an upper face oriented toward the front face 12 . Facing away from the impact rocker 13 , the base part 11 has a lug, into which a recess 18 in the form of a milled-out area is machined. The recess 18 forms a supporting surface 18 . 2 and a bearing surface 18 . 1 at an angle to it. The supporting surface 18 . 2 pointing in the tool-advancing direction (V) transitions to a diverting surface 19 . On the back, the carrier 10 has protrusions 15 , which are used for fixing a rotor of a rotary impact crusher. On both sides of the protrusions 15 , supporting surfaces 14 are provided. In the vicinity of or near the impact rocker 13 , the carrier 10 forms a seating surface 17 . This face is disposed at an angle to the supporting surface 14 on the back. By means of or with the supporting surface 14 and the seating surface 17 , the carrier 10 can be reliably supported on the rotor. As shown in FIG. 1 , four cutting inserts 20 are built into the recess 18 , which are disposed side by side in the longitudinal direction of the carrier 10 .
FIG. 2 shows the arrangement of FIG. 1 in perspective in a rear view. As shown in this view, three protrusions 15 which are separated from one another by grooves are integrally formed onto the base part 11 on the back. Beginning at the back side of the carrier 10 , fastening sockets 16 in the form of bores are made in the carrier 10 . These bores open in the bearing surface 18 . 2 of the recess 18 . Fastening screws 16 . 1 can be passed through the fastening socket 16 and screwed into the cutting inserts 20 , as will be explained hereinafter.
As shown in FIG. 3 , the cutting insert 20 includes a cutting element holder 21 , on which cutting elements 23 and wear plates 22 are fastened. The cutting element holder 21 has a vertical contact surface 21 . 8 , which is adjoined by a bottom 21 . 1 via a chamfer 21 . 10 . In the assembled state, the bottom 21 . 1 is supported on the bearing surface 18 . 1 of the carrier 10 , and the contact surface 21 . 8 is supported on the supporting surface 18 . 2 . The chamfer 21 . 10 guarantees reliable contact with the supporting surface 18 . 2 and bearing surfaces 18 . 1 . At the front, the bottom 21 . 1 transitions to a diagonally extending transitional portion 21 . 2 . The transitional portion 21 . 2 is adjoined by a front face 21 . 3 , which is positioned at an angle greater than 90° relative to the bottom 21 . 1 extending in the tool-advancing direction. This positioning angle is preferably selected within the range between 95° and 120°, to make possible a geometry that is favorable from the standpoint of wear. Above the front face 21 . 3 is an adjoining milled-out area 21 . 5 into which the wear plates 22 are inserted. The milled-out area 21 . 5 is dimensioned so that the surfaces of the wear plates 22 transition flush to the front face 21 . 3 . The milled-out area forms a contact surface 21 . 4 with which the wear plates 22 can be aligned. As a result, simpler manufacture is possible. The wear plates 22 are firmly soldered in the milled-out area 21 . 5 on the back by hard solder.
The milled-out area 21 . 5 is adjoined by a seating surface 21 . 6 . This seating surface 21 . 6 is inclined counter to the tool-advancing direction V and toward the back side of the cutting insert 20 . The cutting element 23 can be firmly soldered to the seating surface 21 . 6 with a flat supporting portion 23 . 5 . The cutting element 23 is dimensioned so that with a protrusion 23 . 4 on its underside, it covers the face end, oriented toward it, of the wear plate 22 , and an impact surface 23 . 3 on the front transitions flush to the front side of the wear plates 22 . This gapless, flush transition prevents crushed material from penetrating and exerting impermissible shear forces on the cutting elements 23 and the wear plates 22 . These shear forces would expose the hard-metal wear plates 22 and cutting elements 23 to the risk of breakage. The impact surface 23 . 3 extends in inclined fashion and points in the tool-advancing direction V. With a free surface 23 . 1 , the impact surface 23 . 3 forms an angle of less than 90°, and in the transition region between the free surface 23 . 1 and the impact surface 23 . 3 , a cutting edge 23 . 2 is formed. The free surface 23 . 1 in turn transitions flush to a diverting surface 21 . 7 of the cutting element holder 21 .
FIG. 4 shows that the cutting elements 23 are provided laterally with side surfaces 23 . 5 that extend in the tool-advancing direction V. Via these side surfaces 23 . 5 , the cutting elements 23 can be lined up with one another in gapless, flush fashion. Per cutting element 23 , two wear plates 22 each are built in, and the two wear plates 22 have a total width that is equivalent to the width of the cutting element 23 .
As shown in FIG. 5 , preferably eight cutting elements 23 are fastened to one cutting element holder 21 . Accordingly, sixteen wear plates 22 are used.
It shown in FIGS. 4 and 5 that on the back side of the cutting element holder 21 , three fastening lugs 21 . 9 protrude past or beyond the contact surface 21 . 8 . The fastening lugs are embodied with a square cross section and are penetrated by a blind-bore-like threaded opening 24 , as shown particularly in FIG. 4 . The threaded opening 24 terminates behind the wear plates 22 in the cutting element holder 21 . The threaded opening 24 has a center longitudinal axis M which can be disposed or positioned in alignment with the fastening socket 16 of the carrier 10 . With the cutting insert 20 , the carrier 10 here has three recesses, which have a cross-sectional shape corresponding to the fastening lugs 21 . 9 . The internal dimensions of these recesses are selected to be slightly larger than the external dimensions of the fastening lug 21 . 9 . In this way, play is created, which enables a limited adjustment of the cutting insert 20 relative to the carrier 10 , when the cutting insert 20 is in an unfixed preassembly position.
FIG. 4 also shows that the diverting surface 21 . 7 transitions flush to the free surface 23 . 1 . Beginning at the cutting edge 23 . 2 , the free surface 23 . 1 is inclined counter to the tool-advancing direction and at an angle α to the advancement normal extending in the tool-advancing direction V. In this way, a self-sharpening geometry is ensured, which maintains the functionality of the sharp-edged cutting edge 23 . 2 .
For assembling the cutting inserts 20 , they are inserted by their fastening lugs 21 . 9 into the corresponding recesses 18 in the carrier 10 . Next, from the back side of the carrier 10 , the fastening screws 16 . 1 are passed through the fastening sockets 16 and screwed into the threaded opening 24 in the cutting element holder 21 . At this time the fastening screws 16 . 1 have not yet been tightened, so that the cutting inserts 20 are in a preassembly position. Next, the cutting inserts 20 are pushed against one another in the longitudinal direction L, as shown in FIG. 5 , of the cutting inserts 20 on the supporting surface 18 . 2 and the bearing surface 18 . 1 , so that they contact one another in gapless fashion. The displacement motion is enabled by the play between the fastening lugs 21 . 9 and the recesses in the carrier 10 . Once the cutting inserts 20 have been pushed against one another, the fastening screws 16 can be tightened with the prescribed torque, and the cutting inserts 20 are then securely fastened to the carrier 10 .
During operational use, wear to the cutting edge 23 . 2 of the cutting elements 23 occurs because of the contact with the rock materials that are to be crushed. In the process, the cutting elements 23 become worn in the vertical direction, such as transversely to the tool-advancing direction V. As FIG. 4 shows, the cross-sectional shape of the cutting elements 23 is selected to be triangular, so that a high proportion of hard material is positioned in the vicinity of or near the cutting edge 23 . 2 . In this way, a long service life is possible in a manner optimized with regard to material.
Once the cutting elements 23 have reached their wear limit, the cutting insert 20 can be replaced without problems. All that has to be done is for the fastening screws 16 to be loosened, and the cutting insert 20 to be replaced by an unworn cutting insert 20 . Under impermissible usage conditions, it can sometimes happen that a cutting element 23 of a cutting insert 20 will break prematurely. In that case, the cutting insert 20 can easily be replaced. This requires merely loosening the fastening screws 16 . 1 of all the cutting inserts 20 , pushing the cutting inserts 20 apart, and then removing the damaged cutting insert 20 . A new cutting insert 20 can be attached, the cutting inserts can be pushed against one another again, and the fastening screws 16 can be tightened. These maintenance jobs can be performed easily and without danger, because the cutting inserts 20 form compact structural units, which are only slight in weight on their own and are easy to handle. | A beater bar for a rock impact crusher, in particular a rotary impact crusher, including a carrier which, in the region of a cutting edge, has a plurality of cutting elements made of a hard material arranged next to one another. For the purpose of simple maintenance and for improved cost-effectiveness of the beater bar, according to this invention two or more cutting elements are fastened on a cutting-element holder, and two or more cutting-element holders can be interchangeably fastened to the carrier. | 1 |
BACKGROUND
1. Field of the Invention
The present invention relates generally to processing of waste materials, and more particularly to processes and systems for treating organic waste materials to form a compost product.
2. Description of the Prior Art
Anaerobic digestion and composting processes have co-existed for many years as disposal alternatives for organic waste materials. Such materials include agricultural materials, “green” wastes, and pre- and post-consumer wastes. The primary objective of anaerobic digestion is the production of a mixture of hydrocarbon gases (“biogas”), which may be utilized as an energy source to generate electricity and/or heat. Any solid material remaining at the completion of the anaerobic digestion process is typically disposed of by conventional methods, such as transferring the material to a landfill. In contrast, composting processes focus on the production of a solid product that may be employed as a soil amendment.
Because of the high capital costs associated with anaerobic digestion equipment, composting has become the dominant method in the United States for the management and re-use of organic waste materials generated in rural and suburban settings. The growing use of composting as a preferred alternative to disposal of organic waste material has made some common environmental problems apparent. These problems include emissions of noxious gases and ozone pre-cursors, runoff from the compost facility, and high energy consumption during material processing. These problems may become particularly acute if the organic waste material contains large amounts of food waste or other high moisture content waste. Commercial-scale composting is also subject to a variety of financial considerations, including capital investment related to accommodating peak seasonal feedstock deliveries, compost process time, and controlling the timing of compost production to match the seasonal demand of the agricultural industry and other compost buyers.
It is therefore an objective of the invention to provide a process and system for treating organic waste materials that avoids or reduces the aforementioned environmental problems and addresses the financial considerations in an economically advantageous manner.
SUMMARY
In a preferred embodiment of the invention, organic waste materials are treated via a multi-stage process involving anaerobic hydrolysis, anaerobic digestion of the liquid hydrolysis product, and aerobic composting of the solids remaining after hydrolysis. The organic waste materials may be pre-treated by adding a amount of liquid inoculant sufficient to raise the moisture content of the organic waste to a minimum of sixty percent. The organic waste material is then placed within a sealed hydrolysis vessel, which may take the form of a cylindrical polymer bag. Hydrolysis of the organic matter within the vessel results in the production of a liquid product, which is removed from the vessel via a conduit that communicates with the vessel's interior. Removal of the liquid may be performed either continuously, at specified intervals, or at the completion of the hydrolysis process.
The liquid hydrolysis product transferred from the vessel, which may be temporarily stored in a holding tank, is passed to a conventional anaerobic digester. In a thermophilic digester, methanogenic bacteria convert organic matter that is dissolved and/or suspended in the liquid hydrolysis product to a biogas product. The biogas product may be combusted prior to release to the atmosphere in order to eliminate or reduce emissions of flammable or otherwise objectionable gaseous species, such as methane. Thermal energy produced by combustion of the biogas may be utilized to supply heat and/or electrical power for processing operations. The liquid digester product remaining after completion of the digestion process may be removed from the digester and employed as inoculant for hydrolysis of subsequently processed organic waste material.
After completion of hydrolysis, the remaining solid waste material may be removed from the vessel and composted under aerobic conditions. The composting process may be implemented as a static reversed air aerobic composting system, wherein the solid waste material is placed in a pile atop a pad adapted with an array of ports that communicate with a manifold. A blower, coupled to the manifold, draws ambient air through the solid waste material and into the ports and manifold. The ambient air drawn through the pile and into the manifold is passed through a biofilter to remove undesirable species before discharge to the atmosphere. Alternatively, after completion of hydrolysis, the remaining solid waste material may be composted using an aerobic windrow process, positive or negative aerated static pile or other suitable process. The end result of the composting process is a decomposed material that may be used as a soil amendment.
The foregoing waste material treatment process present several advantages over prior art techniques, including the reduction of emissions of ozone precursors and other noxious or otherwise objectionable gases (by removal of such species during the hydrolysis process), lowering the net energy requirements associated with the composting process (since energy required for material processing is offset by energy produced by utilization of the biogas product), and the ability to rapidly and inexpensively scale the process to meet peak throughput demands by adjusting the number and capacity of the relatively low-cost hydrolysis vessels.
BRIEF DESCRIPTION OF THE FIGURES
In the accompanying drawings:
FIG. 1 is a symbolic diagram of an organic waste treatment system in accordance with an embodiment of the invention;
FIG. 2 is a symbolic longitudinal cross-sectional view of the flexible hydrolysis vessel of the FIG. 1 system;
FIG. 3 is a flowchart depicting process steps for treating organic waste material, in accordance with an embodiment of the invention; and
FIG. 4 is a symbolic side view of an apparatus for static reverse air composting, in accordance with a specific implementation of the invention.
DETAILED DESCRIPTION
FIG. 1 symbolically depicts the major components of an organic waste treatment system 100 implemented in accordance with an exemplary embodiment of the invention. A flexible hydrolysis vessel 110 contains a volume of organic waste material 115 having relatively high moisture content and density. The hydrolysis vessel 110 has pliable walls formed from a polymer or other material that is substantially impermeable to gases and liquids. The ends of vessel 110 are closed and sealed to provide an anaerobic environment for the hydrolysis of the organic waste material 115 . Details regarding the construction of vessel 100 are set forth below in connection with FIG. 2 .
The vessel 100 rests on a supporting surface 118 , which is sloped along the longitudinal axis of vessel 110 such that the bottom portion of a first end 120 of the vessel 110 is situated lower than the bottom portion of the opposite end 122 of the vessel 110 . This condition causes liquids produced during anaerobic hydrolysis of organic waste 115 to flow under the influence of gravity to a region of the vessel interior proximal to first end 120 . As is described below in connection with FIG. 2 , liquid flow within vessel 110 may be facilitated by placement of one or more perforated pipe structures within the vessel 110 . In one embodiment, the supporting surface 118 is a heated supporting surface.
At the completion of the anaerobic hydrolysis process, or at specified intervals during the anaerobic hydrolysis process, collected liquid (including dissolved and suspended organic compounds) is removed from the interior of the vessel 110 via conduit 124 . The conduit 124 may comprise pipe formed from PVC or other suitable material that is resistant to attack by organic acids and other corrosive compounds contained within the hydrolysis liquids. A normally-closed valve (not shown in FIG. 1 ) integrated with or located exterior to vessel 110 , may be opened to effect flow of the collected liquid out of the vessel. The liquid flows through conduit 124 and into a holding tank 130 . The holding tank 130 serves as a reservoir to store liquid produced during anaerobic hydrolysis of the waste material until digester 140 is available for further processing of the liquid. When digester 140 becomes available, a suitable quantity of liquid is pumped by pump 132 from the holding tank 130 through line 134 into the interior of the digester 140 .
The digester 140 may be in the form of a conventional closed digester vessel in which the hydrolysis liquid product is combined with methane producing bacteria and incubated for a predetermined period to produce biogas and a liquid digester product. The interior of digester 140 may be conventionally adapted with membranes, heaters, and other structures, as appropriate, to facilitate and optimize the digestion process. Digesters of this general description are available from industrial suppliers such as Onsite Power Systems, Inc. of Camarillo, Calif. The biogas is preferably combusted prior to release to the atmosphere to destroy methane (a primary component of the biogas) and other flammable, noxious, and other species for which emission to the environment is undesirable, dangerous, and/or regulated. Thermal energy produced by combustion of the biogas may be utilized for various purposes, including generation of electrical power, which may in turn be used to drive various components of the waste treatment system 100 , including blowers and pumps. An electrical generator 150 (which may comprise, for example, a conventional turbine generator or microturbine) may be provided in the FIG. 1 system for this purpose. Alternatively and/or additionally, hot exhaust gases resulting from biogas combustion may be passed through a heat exchanger to produce heated air and/or liquid streams for use in the digester 140 or other components of the waste treatment system 100 or related apparatus. The exhaust gases from biogas combustion may be subjected to filtration and/or other pollutant control processes, as appropriate, prior to atmospheric venting. In yet another alternative embodiment, the biogas is processed and refrigerated to produce liquid natural gas (LNG), which may be stored or shipped offsite for use as an energy source.
While the system 100 is depicted as having a single hydrolysis vessel 110 and digester 140 , those skilled in the art will recognize that commercial implementations may include any number of hydrolysis vessels and digesters, as suited to a specific application and required throughput. Multiple hydrolysis vessels and/or digesters may be arranged and linked in any suitable arrangement. For example, multiple hydrolysis vessels may be arranged in parallel to supply liquid to a single holding tank and digester. Alternatively, multiple hydrolysis vessels may be coupled to a plurality of digesters, each of which may be brought on-line or off-line as appropriate according to throughput and maintenance requirements.
FIG. 2 is a longitudinal cross-sectional view depicting anaerobic hydrolysis vessel 110 . The vessel 110 may take the form of an elongated, generally cylindrical container having thin walls formed from a polymer material. Desirable properties of the polymer material include impermeability to gases and liquids, high resilience (to avoid tearing), and high resistance to chemical attack from organic acids and other compounds formed during hydrolysis. Containers of this general description are available from commercial suppliers such as Ag-Bag International Limited of Warrenton, Oreg. The dimensions of the vessel 110 may be selected in view of the required throughput, structural integrity, and space considerations. In an exemplary commercial implementation, vessel 110 has a diameter of approximately five to ten feet, and a length in the range of 100–200 feet.
In the foregoing implementation, at least one end of the vessel 110 will initially be open to enable placement of the organic waste material 115 into the vessel 110 . As is described below in connection with FIG. 3 , filling of vessel 110 may be accomplished by using a conventional bagging machine.
A perforated drainage pipe 201 may be placed within the interior of vessel 110 to facilitate the flow of liquids generated during the hydrolysis process to the first (lower) end of the vessel. Pipe 201 is located at or near the bottom portion of the interior and traverses the length of the vessel. Liquids enter pipe 201 through holes in the pipe wall and exit the pipe at a mouth 203 opening to the unfilled region of the vessel adjacent to the vessel's lower end. Placement of perforated pipe 201 within the vessel may be accomplished by employing an apparatus and method substantially similar to that described in U.S. Pat. No. 5,461,843 (“Method for Treatment of Bagged Organic Materials” by Garvin et al.).
Vessel 110 is adapted with a port 202 located proximal to the first (lower) end 120 to enable removal of hydrolysis liquid product. The port 202 is coupleable to conduit 124 by a flange 204 such that accumulated liquids flow into conduit 124 and thereafter into holding tank 130 . Vessel 110 may be continuously coupled to conduit 124 throughout the hydrolysis stage; alternatively, conduit 124 may be coupled to vessel 110 only when drainage of the hydrolysis liquid is desired (such as at periodic intervals during or at the completion of the hydrolysis process). One or more valve structures, which may be integrated with port 202 or located externally thereto, are provided to selectively inhibit or allow the flow of hydrolysis liquids into conduit 124 while preventing the ingress of air and thereby maintaining the anaerobic conditions within the vessel.
FIG. 3 depicts the process steps for treating organic waste material in accordance with an embodiment of the invention. The process 300 will be described in terms of its application to exemplary waste treatment system 100 ; however, the process should not be construed as being limited to implementation in the FIG. 1 system. In step 302 , the organic waste material is pre-treated prior to placement within the vessel 110 . In a typical commercial composting facility, the organic waste material comprises multiple waste streams, including without limitation agricultural waste, food waste, residential lawn/garden waste, and cannery waste. The pre-treatment step 302 may include blending of two or more of these waste streams. The blending proportions (percentages of each waste stream in the organic waste material) may be adjusted to optimize various properties of the organic waste material, such as carbon:nitrogen ratio. The blended material may then be ground to reduce the average particle size and increase surface area available for reaction. According to one implementation, the waste material is ground to a maximum particle size (longest dimension) of 1.5 inches.
The pre-treatment step 302 may further include the addition of a liquid inoculant to the organic waste material 115 . The addition of inoculant supplies the moisture and anaerobic bacteria required for the hydrolysis reactions to occur. Inoculant is available in bulk from commercial suppliers; however, according to a preferred implementation, the inoculant is wholly or partially comprised of the liquid digester product produced by digestion of a previously processed batch of organic waste material 115 . Use of the liquid digester product as the inoculant confers a substantial economic benefit by removing the need to purchase commercial inoculant and avoiding costs associated with disposal/treatment of the liquid digester product. The amount of inoculant added to the organic waste material 115 should be sufficient to raise the moisture content to at least (and preferably significantly greater than) sixty percent by weight. The resultant organic waste material 115 will typically have a density of approximately 800–1000 pounds/cubic yard.
Next, in step 304 , the pretreated organic waste material 115 is placed within the vessel 110 . According to one implementation, placing the organic waste material 115 in the vessel 110 includes placing the vessel 110 on a supporting surface 118 that is heated. Placement of the organic waste material 115 within the vessel 110 may be achieved by employing a bagging machine of the type described in U.S. Pat. No. 5,566,532 and sold by Ag-Bag International Limited. Generally, such machines include a conveyor for transferring material from a hopper into a feed tunnel, and a rotor for compressing the material and propelling the compressed material into an elongated bag having an open end thereof affixed to the tunnel exit. A bagging machine may further include a ram removably received within the interior of vessel 110 for urging the material along the length of the vessel. As is depicted in FIG. 2 , the entire interior volume of vessel 110 is filled with organic waste material 115 except for a region adjacent to first (lower) end 120 , which is left unfilled to accommodate liquid product generated during hydrolysis of the organic waste material 115 . In a typical implementation utilizing a vessel 110 having a length of 200 feet, the unfilled region will have a length of approximately 10 feet. The vessel 110 is sealed at the completion of the placement step to create an anaerobic environment for hydrolysis of the organic waste material 115 . Prior to sealing, air remaining in the vessel 110 (e.g., bag) may be pumped out using a vacuum pump in order to reduce the oxygen concentration within the vessel 110 .
The organic waste material 115 is then incubated within sealed vessel 110 for a specified period in step 306 . During this period, the organic waste material 115 undergoes hydrolysis, wherein bacteria or other agents convert a portion of the hydrocarbon compounds in the waste material to organic acids, alcohols, and/or aldehydes. Hydrolysis of the organic waste material 115 results in the production of a liquid hydrolysis product, which flows under gravity to the unfilled region of vessel 110 . The liquid hydrolysis product contains suspended and dissolved organic compounds, as well as dissolved gases. Removal of these compounds from the organic waste material during the hydrolysis process may substantially reduce emissions of ozone precursors and noxious gases produced in the subsequent composting phase. The time period during which organic waste material 115 undergoes hydrolysis will vary according to feedstock composition, temperature, and digester requirements, but will typically be on the order of three weeks. It is noted that the organic waste material may be stored within vessel 110 for a longer period of time in order to match production of the compost end product to seasonal demand.
Next, in step 308 , the accumulated liquid hydrolysis product is removed from the interior of vessel 110 and transferred through conduit 124 to holding tank 130 . Removal and transfer of the liquid hydrolysis product may be performed continuously, at predetermined intervals during hydrolysis, or after completion of hydrolysis. If removal and transfer of the liquids is performed intermittently, flow of the liquid from the vessel 110 interior may be started and stopped by (respectively) opening and closing a valve associated with port 202 or conduit 124 . The liquid hydrolysis product is subsequently pumped into digester 140 and is incubated under anaerobic conditions to produce a biogas product and a liquid product, which may be used as an inoculant in the manner described above.
In step 310 , the remaining organic waste material 115 (e.g., substantially solid organic waste product) is removed from the vessel 110 and subjected to further decomposition under aerobic conditions. This step may be implemented, for example, as a static reverse air aerobic decomposition process. In this process, which is illustrated by FIG. 4 , the organic waste material 115 is arranged in a pile 402 atop a supporting pad adapted with an array of air ports 404 distributed along the length and/or across the width of the pile. The outer periphery of the pile is exposed to the atmosphere. The air ports 404 communicate with at least one manifold 406 . A blower 408 or similar device reduces the pressure within the manifold below the ambient pressure. The resultant pressure gradient causes ambient air adjacent to the pile to pass through the pile and into air ports 404 and manifold 406 . This action provides a flow of air into the interior of the pile to facilitate aerobic decomposition reactions. The air drawn through manifold 406 is passed through a biofilter to remove any objectionable gas components prior to exhausting the air stream to the atmosphere.
Step 310 may be alternatively implemented by employing any one of a number of suitable prior art techniques, such as the forced-air composting process described in the aforementioned U.S. Pat. No. 5,461,843 or a conventional windrow-based process.
By utilizing the process discussed above, a high-quality compost may be advantageously derived from food waste and other high moisture content feedstocks while avoiding the environmental problems of traditional composting methods and the need for large capital expenditures associated with conventional hydrolysis equipment.
It should be noted that the process and system described above may be advantageously applied to a wide range of organic waste materials, including without limitation municipal solid waste (MSW), biosolids sludge, agricultural wastes, cannery wastes, manures, green and wood wastes, and other waste streams having organic content.
It will be recognized by those skilled in the art that, while the invention has been described above in terms of preferred embodiments, it is not limited thereto. Various features and aspects of the above-described invention may be used individually or jointly. Further, although the invention has been described in the context of its implementation in a particular environment and for particular applications, those skilled in the art will recognize that its usefulness is not limited thereto and that the present invention can be beneficially utilized in any number of environments and implementations. Accordingly, the claims set forth below should be construed in view of the full breadth and spirit of the invention as disclosed herein. | A multi-stage process and system for treating organic waste materials includes steps of hydrolyzing the materials in an anaerobic vessel, transferring the liquid product of hydrolysis to an anaerobic digester, and further decomposing the waste materials under aerobic conditions to yield a compost product usable as a soil amendment. Biogas produced by digestion of the hydrolysis liquid product may be burned to generate electricity or heat, and the liquid digester product may be recirculated for use as an inoculant to aid hydrolysis of subsequently processed batches of waste materials. | 2 |
BACKGROUND OF THE INVENTION
This invention relates to visual display devices and, more particularly to the uniform illumination of display panels.
There are two general methods of illuminating a display panel. The most common utilizes a single light source arranged so that an acceptable level of light is cast on all viewable areas of the display. This method produces a non-uniform light intensity over the viewing area of the display since the light intensity at a specific point is inversely proportional to the square of the distance between the point and the light source. In cases where the display is fairly compact and all of the viewing areas are approximately the same distance from the light source, the non-uniform lighting is not a serious disadvantage. However, where the display is of irregular shape or of rather long, rectangular shape and where the viewing areas are at substantially varying distances from the light source, the variation in light intensity can be undesirable. To help alleviate this problem a second method of illuminating a display panel was utilized whereby multiple light sources are selectively spaced about the panel in an arrangement that reduces the wide variation in light intensity formed with some of the single light source devices. Here again, however, there may be considerable non-uniformity of light intensity within the viewing field. Additional complexities inherent in this method and resulting increased costs detract from its desirability. Other attempts at solving this problem have centered about the use of "frosted glass" defusers and the like. These attempts have not met with complete success. Another attempt at solving this problem is disclosed in British Pat. No. 1,337,055, Oct. 25, 1972, Bubbins, wherein a single light source is positioned at the focal point of a parabolic shaped reflector which produces a planar field of light of uniform intensity. This method, however, has the disadvantage of being bulky and is difficult to incorporate into existing display designs. The present invention overcomes these difficulties of the prior art by the use of a novel but relatively simple device.
SUMMARY OF THE INVENTION
It is an object of this invention to produce a relatively compact visual display device for use with a sewing machine. It is another object of this invention to produce a visual display device illuminated over its entire viewable field with light of substantially uniform intensity.
Other objects and advantages of the invention will become apparent through reference to the accompanying drawings and descriptive matter which illustrates a preferred embodiment of this invention.
According to the present invention there is provided a lighted display having an array of discrete reflective surfaces supported at varying distances from a light source. There is a visual display associated with each reflective surface and positioned for viewing by the operator. Each reflective surface has a reflectivity inversely proportional to the square of its distance from the light source so that the intensity of light reflected by each surface to its respective associated visual display is substantially equal.
BRIEF DESCRIPTION OF THE DRAWINGS
In order that the invention be more fully understood it will now be described by way of example with reference to the accompanying drawings in which:
FIG. 1 is a perspective view of a sewing machine with a partial cut-away showing structure incorporating this invention;
FIG. 2 is a front view of the display device incorporating the teachings of this invention; and
FIG. 3 is an end view taken along lines 3--3 of FIG. 2.
DETAILED DESCRIPTION OF THE INVENTION
Referring to FIGS. 1 through 3 there is shown a sewing machine 2 having a horizontal arm 4 within which is mounted a display panel 6 positioned for easy viewing by the operator. The display panel 6 is transparent to light and has affixed thereto several replicas 8 of stitch patterns that may be selected by the operator and sewn by the machine.
A light pipe 20, made of a transparent thermoplastic resin has a body 24 which is positioned directly adjacent to the display panel 6, and has an extremity 22 projecting downward and into close proximity to a light source or lamp 30. A series of reflective surfaces 40, 42, 44, 46, 48 and 50 are placed in contact with the back surface 26 of the light pipe 20. These reflective surfaces, in the preferred embodiment, are composed of matrices of white dots of paint applied directly to the back surface 26. The reflective surface 48 has fewer white dots per unit area than the surface 50. The surface 46 has fewer dots than the surface 48 and so on to the surface 40 which has the fewest white dots per unit area. Since the surface 40 has the fewest white dots per unit area and each succeeding surface 42 through surface 50 having respectively more white dots per unit area, the surface 40 will have the lowest reflectivity while each succeeding surface 42 through surface 50 will have a respectively higher reflectivity. While the preferred embodiment varies the quantity of white dots per unit area in order to vary reflectivity, a fixed quantity and spacing of dots per unit area could be established and the shape and size of the dots varied. Both methods will work equally well.
The percentage of white dots per unit area for each of the reflective surfaces 40-50 is selected so that the resulting reflectivity of each surface is inversely proportional to the square of the light path distance from the surface to the light source 30 and so that light from the light source 30 will reflect from each of the surfaces 40-50 with substantially equal intensity.
In operation, light from the lamp 30 enters the extremity 22 of the light pipe 20 and spreads throughout the entire interior of the light pipe. As the light moves away from the extremity 22 toward the other end of the light pipe 20, its intensity diminishes. The reflective surfaces 40 through 50 reflect this light outwardly in the direction of the arrow A shown in FIG. 3. The light has an intensity directly proportional to the reflectivity of each surface and to the amount of light received. The change in reflectivity from surface to surface exactly corresponds to and counters the change in amount of light received so that the resulting light that is reflected outwardly in the direction of the arrow A from each surface will be of equal intensity. The light so reflected illuminates the patterns 8 of the display panel 6 for viewing by the operator. The operator may then adjust a pointer or the like, not shown, to select a desired pattern for sewing.
Upon reviewing the present disclosure, a number of alternative constructions will occur to one skilled in the art. Such constructions may utilize various methods to illuminate the discrete reflective surfaces as, for example, fibre optics, direct radiation, back or front illumination et al. Additionally, various means may be utilized to vary the reflectivity of the reflective surfaces as, for example, lines painted on or otherwise applied to the surface or variations in color or texture of the surface. All such alternative constructions are considered to be within the spirit and scope of this disclosure and are presented here as examples for illustrative purposes only and are not to be deemed as limitations of this invention. | A lighted display device having an array of discrete reflective surfaces each of which is associated with a visual display. The reflectivity of each of the surfaces is established so that the light reflected to, and illuminating, each associated visual display is of equal intensity independent of the distance of the reflective surface from the light source. | 3 |
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